diff --git a/lib/.gitattributes b/lib/.gitattributes
index fcadb2cf979..07764a78d98 100644
--- a/lib/.gitattributes
+++ b/lib/.gitattributes
@@ -1 +1 @@
-* text eol=lf
+* text eol=lf
\ No newline at end of file
diff --git a/lib/cancellationToken.js b/lib/cancellationToken.js
index 39000bb9f7d..d63145f3fc5 100644
--- a/lib/cancellationToken.js
+++ b/lib/cancellationToken.js
@@ -13,6 +13,7 @@ See the Apache Version 2.0 License for specific language governing permissions
 and limitations under the License.
 ***************************************************************************** */
 
+
 "use strict";
 var fs = require("fs");
 function pipeExists(name) {
diff --git a/lib/tsc.js b/lib/tsc.js
index 83058b911c5..00c1db6c1b5 100644
--- a/lib/tsc.js
+++ b/lib/tsc.js
@@ -13,100 +13,20 @@ See the Apache Version 2.0 License for specific language governing permissions
 and limitations under the License.
 ***************************************************************************** */
 
+
 "use strict";"use strict";
-/*@internal*/
-var ts;
-(function (ts) {
-    /** Gets a timestamp with (at least) ms resolution */
-    ts.timestamp = typeof performance !== "undefined" && performance.now ? function () { return performance.now(); } : Date.now ? Date.now : function () { return +(new Date()); };
-})(ts || (ts = {}));
-/*@internal*/
-/** Performance measurements for the compiler. */
-(function (ts) {
-    var performance;
-    (function (performance) {
-        // NOTE: cannot use ts.noop as core.ts loads after this
-        var profilerEvent = typeof onProfilerEvent === "function" && onProfilerEvent.profiler === true ? onProfilerEvent : function () { };
-        var enabled = false;
-        var profilerStart = 0;
-        var counts;
-        var marks;
-        var measures;
-        /**
-         * Marks a performance event.
-         *
-         * @param markName The name of the mark.
-         */
-        function mark(markName) {
-            if (enabled) {
-                marks.set(markName, ts.timestamp());
-                counts.set(markName, (counts.get(markName) || 0) + 1);
-                profilerEvent(markName);
-            }
-        }
-        performance.mark = mark;
-        /**
-         * Adds a performance measurement with the specified name.
-         *
-         * @param measureName The name of the performance measurement.
-         * @param startMarkName The name of the starting mark. If not supplied, the point at which the
-         *      profiler was enabled is used.
-         * @param endMarkName The name of the ending mark. If not supplied, the current timestamp is
-         *      used.
-         */
-        function measure(measureName, startMarkName, endMarkName) {
-            if (enabled) {
-                var end = endMarkName && marks.get(endMarkName) || ts.timestamp();
-                var start = startMarkName && marks.get(startMarkName) || profilerStart;
-                measures.set(measureName, (measures.get(measureName) || 0) + (end - start));
-            }
-        }
-        performance.measure = measure;
-        /**
-         * Gets the number of times a marker was encountered.
-         *
-         * @param markName The name of the mark.
-         */
-        function getCount(markName) {
-            return counts && counts.get(markName) || 0;
-        }
-        performance.getCount = getCount;
-        /**
-         * Gets the total duration of all measurements with the supplied name.
-         *
-         * @param measureName The name of the measure whose durations should be accumulated.
-         */
-        function getDuration(measureName) {
-            return measures && measures.get(measureName) || 0;
-        }
-        performance.getDuration = getDuration;
-        /**
-         * Iterate over each measure, performing some action
-         *
-         * @param cb The action to perform for each measure
-         */
-        function forEachMeasure(cb) {
-            measures.forEach(function (measure, key) {
-                cb(key, measure);
-            });
-        }
-        performance.forEachMeasure = forEachMeasure;
-        /** Enables (and resets) performance measurements for the compiler. */
-        function enable() {
-            counts = ts.createMap();
-            marks = ts.createMap();
-            measures = ts.createMap();
-            enabled = true;
-            profilerStart = ts.timestamp();
-        }
-        performance.enable = enable;
-        /** Disables performance measurements for the compiler. */
-        function disable() {
-            enabled = false;
-        }
-        performance.disable = disable;
-    })(performance = ts.performance || (ts.performance = {}));
-})(ts || (ts = {}));
+var __assign = (this && this.__assign) || Object.assign || function(t) {
+    for (var s, i = 1, n = arguments.length; i < n; i++) {
+        s = arguments[i];
+        for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
+            t[p] = s[p];
+    }
+    return t;
+};
+var __makeTemplateObject = (this && this.__makeTemplateObject) || function (cooked, raw) {
+    if (Object.defineProperty) { Object.defineProperty(cooked, "raw", { value: raw }); } else { cooked.raw = raw; }
+    return cooked;
+};
 var ts;
 (function (ts) {
     // WARNING: The script `configureNightly.ts` uses a regexp to parse out these values.
@@ -115,14 +35,17 @@ var ts;
     /** The version of the TypeScript compiler release */
     ts.version = ts.versionMajorMinor + ".0-dev";
 })(ts || (ts = {}));
-/* @internal */
 (function (ts) {
+    /* @internal */
     var Comparison;
     (function (Comparison) {
         Comparison[Comparison["LessThan"] = -1] = "LessThan";
         Comparison[Comparison["EqualTo"] = 0] = "EqualTo";
         Comparison[Comparison["GreaterThan"] = 1] = "GreaterThan";
     })(Comparison = ts.Comparison || (ts.Comparison = {}));
+})(ts || (ts = {}));
+/* @internal */
+(function (ts) {
     /** Create a MapLike with good performance. */
     function createDictionaryObject() {
         var map = Object.create(/*prototype*/ null); // tslint:disable-line:no-null-keyword
@@ -1984,16 +1907,99 @@ var ts;
     }
     ts.enumerateInsertsAndDeletes = enumerateInsertsAndDeletes;
 })(ts || (ts = {}));
-//# sourceMappingURL=core.js.map
-"use strict";
-var __assign = (this && this.__assign) || Object.assign || function(t) {
-    for (var s, i = 1, n = arguments.length; i < n; i++) {
-        s = arguments[i];
-        for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
-            t[p] = s[p];
-    }
-    return t;
-};
+/*@internal*/
+var ts;
+(function (ts) {
+    /** Gets a timestamp with (at least) ms resolution */
+    ts.timestamp = typeof performance !== "undefined" && performance.now ? function () { return performance.now(); } : Date.now ? Date.now : function () { return +(new Date()); };
+})(ts || (ts = {}));
+/*@internal*/
+/** Performance measurements for the compiler. */
+(function (ts) {
+    var performance;
+    (function (performance) {
+        // NOTE: cannot use ts.noop as core.ts loads after this
+        var profilerEvent = typeof onProfilerEvent === "function" && onProfilerEvent.profiler === true ? onProfilerEvent : function () { };
+        var enabled = false;
+        var profilerStart = 0;
+        var counts;
+        var marks;
+        var measures;
+        /**
+         * Marks a performance event.
+         *
+         * @param markName The name of the mark.
+         */
+        function mark(markName) {
+            if (enabled) {
+                marks.set(markName, ts.timestamp());
+                counts.set(markName, (counts.get(markName) || 0) + 1);
+                profilerEvent(markName);
+            }
+        }
+        performance.mark = mark;
+        /**
+         * Adds a performance measurement with the specified name.
+         *
+         * @param measureName The name of the performance measurement.
+         * @param startMarkName The name of the starting mark. If not supplied, the point at which the
+         *      profiler was enabled is used.
+         * @param endMarkName The name of the ending mark. If not supplied, the current timestamp is
+         *      used.
+         */
+        function measure(measureName, startMarkName, endMarkName) {
+            if (enabled) {
+                var end = endMarkName && marks.get(endMarkName) || ts.timestamp();
+                var start = startMarkName && marks.get(startMarkName) || profilerStart;
+                measures.set(measureName, (measures.get(measureName) || 0) + (end - start));
+            }
+        }
+        performance.measure = measure;
+        /**
+         * Gets the number of times a marker was encountered.
+         *
+         * @param markName The name of the mark.
+         */
+        function getCount(markName) {
+            return counts && counts.get(markName) || 0;
+        }
+        performance.getCount = getCount;
+        /**
+         * Gets the total duration of all measurements with the supplied name.
+         *
+         * @param measureName The name of the measure whose durations should be accumulated.
+         */
+        function getDuration(measureName) {
+            return measures && measures.get(measureName) || 0;
+        }
+        performance.getDuration = getDuration;
+        /**
+         * Iterate over each measure, performing some action
+         *
+         * @param cb The action to perform for each measure
+         */
+        function forEachMeasure(cb) {
+            measures.forEach(function (measure, key) {
+                cb(key, measure);
+            });
+        }
+        performance.forEachMeasure = forEachMeasure;
+        /** Enables (and resets) performance measurements for the compiler. */
+        function enable() {
+            counts = ts.createMap();
+            marks = ts.createMap();
+            measures = ts.createMap();
+            enabled = true;
+            profilerStart = ts.timestamp();
+        }
+        performance.enable = enable;
+        /** Disables performance measurements for the compiler. */
+        function disable() {
+            enabled = false;
+        }
+        performance.disable = disable;
+    })(performance = ts.performance || (ts.performance = {}));
+})(ts || (ts = {}));
 var ts;
 (function (ts) {
     // token > SyntaxKind.Identifier => token is a keyword
@@ -4270,8 +4276,8 @@ var ts;
                     var entries = _fs.readdirSync(path || ".").sort();
                     var files = [];
                     var directories = [];
-                    for (var _i = 0, entries_1 = entries; _i < entries_1.length; _i++) {
-                        var entry = entries_1[_i];
+                    for (var _i = 0, entries_2 = entries; _i < entries_2.length; _i++) {
+                        var entry = entries_2[_i];
                         // This is necessary because on some file system node fails to exclude
                         // "." and "..". See https://github.com/nodejs/node/issues/4002
                         if (entry === "." || entry === "..") {
@@ -4451,7 +4457,7 @@ var ts;
     }
 })(ts || (ts = {}));
 // <auto-generated />
-// generated from './diagnosticInformationMap.generated.ts' by 'src\parser'
+// generated from './diagnosticInformationMap.generated.ts' by 'src\compiler'
 /* @internal */
 var ts;
 (function (ts) {
@@ -7445,11 +7451,6 @@ var ts;
 /** Non-internal stuff goes here */
 var ts;
 (function (ts) {
-    ts.emptyArray = [];
-    function closeFileWatcher(watcher) {
-        watcher.close();
-    }
-    ts.closeFileWatcher = closeFileWatcher;
     function isExternalModuleNameRelative(moduleName) {
         // TypeScript 1.0 spec (April 2014): 11.2.1
         // An external module name is "relative" if the first term is "." or "..".
@@ -7461,20 +7462,10 @@ var ts;
         return ts.sortAndDeduplicate(diagnostics, ts.compareDiagnostics);
     }
     ts.sortAndDeduplicateDiagnostics = sortAndDeduplicateDiagnostics;
-    function toPath(fileName, basePath, getCanonicalFileName) {
-        var nonCanonicalizedPath = ts.isRootedDiskPath(fileName)
-            ? ts.normalizePath(fileName)
-            : ts.getNormalizedAbsolutePath(fileName, basePath);
-        return getCanonicalFileName(nonCanonicalizedPath);
-    }
-    ts.toPath = toPath;
-    function hasEntries(map) {
-        return !!map && !!map.size;
-    }
-    ts.hasEntries = hasEntries;
 })(ts || (ts = {}));
 /* @internal */
 (function (ts) {
+    ts.emptyArray = [];
     ts.resolvingEmptyArray = [];
     ts.emptyMap = ts.createMap();
     ts.emptyUnderscoreEscapedMap = ts.emptyMap;
@@ -7497,6 +7488,10 @@ var ts;
         return new ts.MapCtr();
     }
     ts.createUnderscoreEscapedMap = createUnderscoreEscapedMap;
+    function hasEntries(map) {
+        return !!map && !!map.size;
+    }
+    ts.hasEntries = hasEntries;
     function createSymbolTable(symbols) {
         var result = ts.createMap();
         if (symbols) {
@@ -7543,6 +7538,13 @@ var ts;
             reportPrivateInBaseOfClassExpression: ts.noop,
         };
     }
+    function toPath(fileName, basePath, getCanonicalFileName) {
+        var nonCanonicalizedPath = ts.isRootedDiskPath(fileName)
+            ? ts.normalizePath(fileName)
+            : ts.getNormalizedAbsolutePath(fileName, basePath);
+        return getCanonicalFileName(nonCanonicalizedPath);
+    }
+    ts.toPath = toPath;
     function changesAffectModuleResolution(oldOptions, newOptions) {
         return !oldOptions ||
             (oldOptions.module !== newOptions.module) ||
@@ -10372,7 +10374,7 @@ var ts;
      */
     function getExternalModuleNameFromPath(host, fileName, referencePath) {
         var getCanonicalFileName = function (f) { return host.getCanonicalFileName(f); };
-        var dir = ts.toPath(referencePath ? ts.getDirectoryPath(referencePath) : host.getCommonSourceDirectory(), host.getCurrentDirectory(), getCanonicalFileName);
+        var dir = toPath(referencePath ? ts.getDirectoryPath(referencePath) : host.getCommonSourceDirectory(), host.getCurrentDirectory(), getCanonicalFileName);
         var filePath = ts.getNormalizedAbsolutePath(fileName, host.getCurrentDirectory());
         var relativePath = ts.getRelativePathToDirectoryOrUrl(dir, filePath, dir, getCanonicalFileName, /*isAbsolutePathAnUrl*/ false);
         var extensionless = ts.removeFileExtension(relativePath);
@@ -11280,6 +11282,10 @@ var ts;
         return options.watch && options.hasOwnProperty("watch");
     }
     ts.isWatchSet = isWatchSet;
+    function closeFileWatcher(watcher) {
+        watcher.close();
+    }
+    ts.closeFileWatcher = closeFileWatcher;
     function getCheckFlags(symbol) {
         return symbol.flags & 33554432 /* Transient */ ? symbol.checkFlags : 0;
     }
@@ -13702,6 +13708,9 @@ var ts;
         return node.kind === 9 /* StringLiteral */ || node.kind === 13 /* NoSubstitutionTemplateLiteral */;
     }
     ts.isStringLiteralLike = isStringLiteralLike;
+})(ts || (ts = {}));
+/* @internal */
+(function (ts) {
     /** @internal */
     function isNamedImportsOrExports(node) {
         return node.kind === 247 /* NamedImports */ || node.kind === 251 /* NamedExports */;
@@ -13718,7 +13727,7 @@ var ts;
     }
     function Type(checker, flags) {
         this.flags = flags;
-        if (Debug.isDebugging) {
+        if (ts.Debug.isDebugging) {
             this.checker = checker;
         }
     }
@@ -13749,9 +13758,10 @@ var ts;
         getSignatureConstructor: function () { return Signature; },
         getSourceMapSourceConstructor: function () { return SourceMapSource; },
     };
+    /* @internal */
     function formatStringFromArgs(text, args, baseIndex) {
         if (baseIndex === void 0) { baseIndex = 0; }
-        return text.replace(/{(\d+)}/g, function (_match, index) { return Debug.assertDefined(args[+index + baseIndex]); });
+        return text.replace(/{(\d+)}/g, function (_match, index) { return ts.Debug.assertDefined(args[+index + baseIndex]); });
     }
     ts.formatStringFromArgs = formatStringFromArgs;
     function getLocaleSpecificMessage(message) {
@@ -13759,11 +13769,11 @@ var ts;
     }
     ts.getLocaleSpecificMessage = getLocaleSpecificMessage;
     function createFileDiagnostic(file, start, length, message) {
-        Debug.assertGreaterThanOrEqual(start, 0);
-        Debug.assertGreaterThanOrEqual(length, 0);
+        ts.Debug.assertGreaterThanOrEqual(start, 0);
+        ts.Debug.assertGreaterThanOrEqual(length, 0);
         if (file) {
-            Debug.assertLessThanOrEqual(start, file.text.length);
-            Debug.assertLessThanOrEqual(start + length, file.text.length);
+            ts.Debug.assertLessThanOrEqual(start, file.text.length);
+            ts.Debug.assertLessThanOrEqual(start + length, file.text.length);
         }
         var text = getLocaleSpecificMessage(message);
         if (arguments.length > 4) {
@@ -13805,6 +13815,7 @@ var ts;
         };
     }
     ts.createCompilerDiagnostic = createCompilerDiagnostic;
+    /* @internal */
     function createCompilerDiagnosticFromMessageChain(chain) {
         return {
             file: undefined,
@@ -13841,6 +13852,7 @@ var ts;
     function getDiagnosticFilePath(diagnostic) {
         return diagnostic.file ? diagnostic.file.path : undefined;
     }
+    /* @internal */
     function compareDiagnostics(d1, d2) {
         return ts.compareStringsCaseSensitive(getDiagnosticFilePath(d1), getDiagnosticFilePath(d2)) ||
             ts.compareValues(d1.start, d2.start) ||
@@ -14055,7 +14067,7 @@ var ts;
     ts.getRootLength = getRootLength;
     // TODO(rbuckton): replace references with `resolvePath`
     function normalizePath(path) {
-        return resolvePath(path);
+        return ts.resolvePath(path);
     }
     ts.normalizePath = normalizePath;
     function normalizePathAndParts(path) {
@@ -14063,7 +14075,7 @@ var ts;
         var _a = reducePathComponents(getPathComponents(path)), root = _a[0], parts = _a.slice(1);
         if (parts.length) {
             var joinedParts = root + parts.join(ts.directorySeparator);
-            return { path: hasTrailingDirectorySeparator(path) ? ensureTrailingDirectorySeparator(joinedParts) : joinedParts, parts: parts };
+            return { path: ts.hasTrailingDirectorySeparator(path) ? ts.ensureTrailingDirectorySeparator(joinedParts) : joinedParts, parts: parts };
         }
         else {
             return { path: root, parts: parts };
@@ -14078,7 +14090,7 @@ var ts;
             return path;
         // return the leading portion of the path up to the last (non-terminal) directory separator
         // but not including any trailing directory separator.
-        path = removeTrailingDirectorySeparator(path);
+        path = ts.removeTrailingDirectorySeparator(path);
         return path.slice(0, Math.max(rootLength, path.lastIndexOf(ts.directorySeparator)));
     }
     ts.getDirectoryPath = getDirectoryPath;
@@ -14106,10 +14118,11 @@ var ts;
         return rootLength > 0 && rootLength === path.length;
     }
     ts.isDiskPathRoot = isDiskPathRoot;
+    /* @internal */
     function convertToRelativePath(absoluteOrRelativePath, basePath, getCanonicalFileName) {
         return !isRootedDiskPath(absoluteOrRelativePath)
             ? absoluteOrRelativePath
-            : getRelativePathToDirectoryOrUrl(basePath, absoluteOrRelativePath, basePath, getCanonicalFileName, /*isAbsolutePathAnUrl*/ false);
+            : ts.getRelativePathToDirectoryOrUrl(basePath, absoluteOrRelativePath, basePath, getCanonicalFileName, /*isAbsolutePathAnUrl*/ false);
     }
     ts.convertToRelativePath = convertToRelativePath;
     function pathComponents(path, rootLength) {
@@ -14127,7 +14140,7 @@ var ts;
      */
     function getPathComponents(path, currentDirectory) {
         if (currentDirectory === void 0) { currentDirectory = ""; }
-        path = combinePaths(currentDirectory, path);
+        path = ts.combinePaths(currentDirectory, path);
         var rootLength = getRootLength(path);
         return pathComponents(path, rootLength);
     }
@@ -14182,15 +14195,18 @@ var ts;
     function getPathFromPathComponents(pathComponents) {
         if (pathComponents.length === 0)
             return "";
-        var root = pathComponents[0] && ensureTrailingDirectorySeparator(pathComponents[0]);
+        var root = pathComponents[0] && ts.ensureTrailingDirectorySeparator(pathComponents[0]);
         if (pathComponents.length === 1)
             return root;
         return root + pathComponents.slice(1).join(ts.directorySeparator);
     }
     ts.getPathFromPathComponents = getPathFromPathComponents;
+})(ts || (ts = {}));
+/* @internal */
+(function (ts) {
     function getPathComponentsRelativeTo(from, to, stringEqualityComparer, getCanonicalFileName) {
-        var fromComponents = reducePathComponents(getPathComponents(from));
-        var toComponents = reducePathComponents(getPathComponents(to));
+        var fromComponents = ts.reducePathComponents(ts.getPathComponents(from));
+        var toComponents = ts.reducePathComponents(ts.getPathComponents(to));
         var start;
         for (start = 0; start < fromComponents.length && start < toComponents.length; start++) {
             var fromComponent = getCanonicalFileName(fromComponents[start]);
@@ -14209,26 +14225,27 @@ var ts;
         }
         return [""].concat(relative, components);
     }
+    ts.getPathComponentsRelativeTo = getPathComponentsRelativeTo;
     function getRelativePathFromFile(from, to, getCanonicalFileName) {
-        return ensurePathIsNonModuleName(getRelativePathFromDirectory(getDirectoryPath(from), to, getCanonicalFileName));
+        return ensurePathIsNonModuleName(getRelativePathFromDirectory(ts.getDirectoryPath(from), to, getCanonicalFileName));
     }
     ts.getRelativePathFromFile = getRelativePathFromFile;
     function getRelativePathFromDirectory(fromDirectory, to, getCanonicalFileNameOrIgnoreCase) {
-        Debug.assert((getRootLength(fromDirectory) > 0) === (getRootLength(to) > 0), "Paths must either both be absolute or both be relative");
+        Debug.assert((ts.getRootLength(fromDirectory) > 0) === (ts.getRootLength(to) > 0), "Paths must either both be absolute or both be relative");
         var getCanonicalFileName = typeof getCanonicalFileNameOrIgnoreCase === "function" ? getCanonicalFileNameOrIgnoreCase : ts.identity;
         var ignoreCase = typeof getCanonicalFileNameOrIgnoreCase === "boolean" ? getCanonicalFileNameOrIgnoreCase : false;
         var pathComponents = getPathComponentsRelativeTo(fromDirectory, to, ignoreCase ? ts.equateStringsCaseInsensitive : ts.equateStringsCaseSensitive, getCanonicalFileName);
-        return getPathFromPathComponents(pathComponents);
+        return ts.getPathFromPathComponents(pathComponents);
     }
     ts.getRelativePathFromDirectory = getRelativePathFromDirectory;
     function getRelativePathToDirectoryOrUrl(directoryPathOrUrl, relativeOrAbsolutePath, currentDirectory, getCanonicalFileName, isAbsolutePathAnUrl) {
         var pathComponents = getPathComponentsRelativeTo(resolvePath(currentDirectory, directoryPathOrUrl), resolvePath(currentDirectory, relativeOrAbsolutePath), ts.equateStringsCaseSensitive, getCanonicalFileName);
         var firstComponent = pathComponents[0];
-        if (isAbsolutePathAnUrl && isRootedDiskPath(firstComponent)) {
+        if (isAbsolutePathAnUrl && ts.isRootedDiskPath(firstComponent)) {
             var prefix = firstComponent.charAt(0) === ts.directorySeparator ? "file://" : "file:///";
             pathComponents[0] = prefix + firstComponent;
         }
-        return getPathFromPathComponents(pathComponents);
+        return ts.getPathFromPathComponents(pathComponents);
     }
     ts.getRelativePathToDirectoryOrUrl = getRelativePathToDirectoryOrUrl;
     /**
@@ -14236,19 +14253,19 @@ var ts;
      * with `./` or `../`) so as not to be confused with an unprefixed module name.
      */
     function ensurePathIsNonModuleName(path) {
-        return getRootLength(path) === 0 && !pathIsRelative(path) ? "./" + path : path;
+        return ts.getRootLength(path) === 0 && !ts.pathIsRelative(path) ? "./" + path : path;
     }
     ts.ensurePathIsNonModuleName = ensurePathIsNonModuleName;
     function getBaseFileName(path, extensions, ignoreCase) {
-        path = normalizeSlashes(path);
+        path = ts.normalizeSlashes(path);
         // if the path provided is itself the root, then it has not file name.
-        var rootLength = getRootLength(path);
+        var rootLength = ts.getRootLength(path);
         if (rootLength === path.length)
             return "";
         // return the trailing portion of the path starting after the last (non-terminal) directory
         // separator but not including any trailing directory separator.
         path = removeTrailingDirectorySeparator(path);
-        var name = path.slice(Math.max(getRootLength(path), path.lastIndexOf(ts.directorySeparator) + 1));
+        var name = path.slice(Math.max(ts.getRootLength(path), path.lastIndexOf(ts.directorySeparator) + 1));
         var extension = extensions !== undefined && ignoreCase !== undefined ? getAnyExtensionFromPath(name, extensions, ignoreCase) : undefined;
         return extension ? name.slice(0, name.length - extension.length) : name;
     }
@@ -14262,13 +14279,13 @@ var ts;
             paths[_i - 1] = arguments[_i];
         }
         if (path)
-            path = normalizeSlashes(path);
+            path = ts.normalizeSlashes(path);
         for (var _a = 0, paths_1 = paths; _a < paths_1.length; _a++) {
             var relativePath = paths_1[_a];
             if (!relativePath)
                 continue;
-            relativePath = normalizeSlashes(relativePath);
-            if (!path || getRootLength(relativePath) !== 0) {
+            relativePath = ts.normalizeSlashes(relativePath);
+            if (!path || ts.getRootLength(relativePath) !== 0) {
                 path = relativePath;
             }
             else {
@@ -14287,8 +14304,8 @@ var ts;
         for (var _i = 1; _i < arguments.length; _i++) {
             paths[_i - 1] = arguments[_i];
         }
-        var combined = ts.some(paths) ? combinePaths.apply(void 0, [path].concat(paths)) : normalizeSlashes(path);
-        var normalized = getPathFromPathComponents(reducePathComponents(getPathComponents(combined)));
+        var combined = ts.some(paths) ? combinePaths.apply(void 0, [path].concat(paths)) : ts.normalizeSlashes(path);
+        var normalized = ts.getPathFromPathComponents(ts.reducePathComponents(ts.getPathComponents(combined)));
         return normalized && hasTrailingDirectorySeparator(combined) ? ensureTrailingDirectorySeparator(normalized) : normalized;
     }
     ts.resolvePath = resolvePath;
@@ -14323,8 +14340,8 @@ var ts;
             return -1 /* LessThan */;
         if (b === undefined)
             return 1 /* GreaterThan */;
-        var aComponents = reducePathComponents(getPathComponents(a));
-        var bComponents = reducePathComponents(getPathComponents(b));
+        var aComponents = ts.reducePathComponents(ts.getPathComponents(a));
+        var bComponents = ts.reducePathComponents(ts.getPathComponents(b));
         var sharedLength = Math.min(aComponents.length, bComponents.length);
         for (var i = 0; i < sharedLength; i++) {
             var stringComparer = i === 0 ? ts.compareStringsCaseInsensitive : componentComparer;
@@ -14372,8 +14389,8 @@ var ts;
             return false;
         if (parent === child)
             return true;
-        var parentComponents = reducePathComponents(getPathComponents(parent));
-        var childComponents = reducePathComponents(getPathComponents(child));
+        var parentComponents = ts.reducePathComponents(ts.getPathComponents(parent));
+        var childComponents = ts.reducePathComponents(ts.getPathComponents(child));
         if (childComponents.length < parentComponents.length) {
             return false;
         }
@@ -14476,7 +14493,7 @@ var ts;
         var singleAsteriskRegexFragment = _a.singleAsteriskRegexFragment, doubleAsteriskRegexFragment = _a.doubleAsteriskRegexFragment, replaceWildcardCharacter = _a.replaceWildcardCharacter;
         var subpattern = "";
         var hasWrittenComponent = false;
-        var components = getNormalizedPathComponents(spec, basePath);
+        var components = ts.getNormalizedPathComponents(spec, basePath);
         var lastComponent = ts.last(components);
         if (usage !== "exclude" && lastComponent === "**") {
             return undefined;
@@ -14543,8 +14560,8 @@ var ts;
     }
     /** @param path directory of the tsconfig.json */
     function getFileMatcherPatterns(path, excludes, includes, useCaseSensitiveFileNames, currentDirectory) {
-        path = normalizePath(path);
-        currentDirectory = normalizePath(currentDirectory);
+        path = ts.normalizePath(path);
+        currentDirectory = ts.normalizePath(currentDirectory);
         var absolutePath = combinePaths(currentDirectory, path);
         return {
             includeFilePatterns: ts.map(getRegularExpressionsForWildcards(includes, absolutePath, "files"), function (pattern) { return "^" + pattern + "$"; }),
@@ -14561,8 +14578,8 @@ var ts;
     ts.getRegexFromPattern = getRegexFromPattern;
     /** @param path directory of the tsconfig.json */
     function matchFiles(path, extensions, excludes, includes, useCaseSensitiveFileNames, currentDirectory, depth, getFileSystemEntries) {
-        path = normalizePath(path);
-        currentDirectory = normalizePath(currentDirectory);
+        path = ts.normalizePath(path);
+        currentDirectory = ts.normalizePath(currentDirectory);
         var patterns = getFileMatcherPatterns(path, excludes, includes, useCaseSensitiveFileNames, currentDirectory);
         var includeFileRegexes = patterns.includeFilePatterns && patterns.includeFilePatterns.map(function (pattern) { return getRegexFromPattern(pattern, useCaseSensitiveFileNames); });
         var includeDirectoryRegex = patterns.includeDirectoryPattern && getRegexFromPattern(patterns.includeDirectoryPattern, useCaseSensitiveFileNames);
@@ -14629,7 +14646,7 @@ var ts;
                 var include = includes_1[_i];
                 // We also need to check the relative paths by converting them to absolute and normalizing
                 // in case they escape the base path (e.g "..\somedirectory")
-                var absolute = isRootedDiskPath(include) ? include : normalizePath(combinePaths(path, include));
+                var absolute = ts.isRootedDiskPath(include) ? include : ts.normalizePath(combinePaths(path, include));
                 // Append the literal and canonical candidate base paths.
                 includeBasePaths.push(getIncludeBasePath(absolute));
             }
@@ -14655,7 +14672,7 @@ var ts;
             // No "*" or "?" in the path
             return !hasExtension(absolute)
                 ? absolute
-                : removeTrailingDirectorySeparator(getDirectoryPath(absolute));
+                : removeTrailingDirectorySeparator(ts.getDirectoryPath(absolute));
         }
         return absolute.substring(0, absolute.lastIndexOf(ts.directorySeparator, wildcardOffset));
     }
@@ -14832,7 +14849,7 @@ var ts;
     })(Debug = ts.Debug || (ts.Debug = {}));
     function tryParsePattern(pattern) {
         // This should be verified outside of here and a proper error thrown.
-        Debug.assert(hasZeroOrOneAsteriskCharacter(pattern));
+        Debug.assert(ts.hasZeroOrOneAsteriskCharacter(pattern));
         var indexOfStar = pattern.indexOf("*");
         return indexOfStar === -1 ? undefined : {
             prefix: pattern.substr(0, indexOfStar),
@@ -14875,8 +14892,8 @@ var ts;
     function getAnyExtensionFromPathWorker(path, extensions, stringEqualityComparer) {
         if (typeof extensions === "string")
             extensions = [extensions];
-        for (var _i = 0, extensions_1 = extensions; _i < extensions_1.length; _i++) {
-            var extension = extensions_1[_i];
+        for (var _i = 0, extensions_2 = extensions; _i < extensions_2.length; _i++) {
+            var extension = extensions_2[_i];
             if (!ts.startsWith(extension, "."))
                 extension = "." + extension;
             if (path.length >= extension.length && path.charAt(path.length - extension.length) === ".") {
@@ -21349,8 +21366,8 @@ var ts;
                 array._children = undefined;
                 array.pos += delta;
                 array.end += delta;
-                for (var _i = 0, array_1 = array; _i < array_1.length; _i++) {
-                    var node = array_1[_i];
+                for (var _i = 0, array_8 = array; _i < array_8.length; _i++) {
+                    var node = array_8[_i];
                     visitNode(node);
                 }
             }
@@ -21500,8 +21517,8 @@ var ts;
                     array._children = undefined;
                     // Adjust the pos or end (or both) of the intersecting array accordingly.
                     adjustIntersectingElement(array, changeStart, changeRangeOldEnd, changeRangeNewEnd, delta);
-                    for (var _i = 0, array_2 = array; _i < array_2.length; _i++) {
-                        var node = array_2[_i];
+                    for (var _i = 0, array_9 = array; _i < array_9.length; _i++) {
+                        var node = array_9[_i];
                         visitNode(node);
                     }
                     return;
@@ -25337,20 +25354,6 @@ var ts;
         return value !== undefined ? { value: value } : undefined;
     }
 })(ts || (ts = {}));
-//# sourceMappingURL=parser.js.map
-"use strict";
-var __assign = (this && this.__assign) || Object.assign || function(t) {
-    for (var s, i = 1, n = arguments.length; i < n; i++) {
-        s = arguments[i];
-        for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
-            t[p] = s[p];
-    }
-    return t;
-};
-var __makeTemplateObject = (this && this.__makeTemplateObject) || function (cooked, raw) {
-    if (Object.defineProperty) { Object.defineProperty(cooked, "raw", { value: raw }); } else { cooked.raw = raw; }
-    return cooked;
-};
 /* @internal */
 var ts;
 (function (ts) {
@@ -25911,8 +25914,8 @@ var ts;
                 var savedSubtreeTransformFlags = subtreeTransformFlags;
                 subtreeTransformFlags = 0 /* None */;
                 var nodeArrayFlags = 0 /* None */;
-                for (var _i = 0, nodes_1 = nodes; _i < nodes_1.length; _i++) {
-                    var node = nodes_1[_i];
+                for (var _i = 0, nodes_2 = nodes; _i < nodes_2.length; _i++) {
+                    var node = nodes_2[_i];
                     bindFunction(node);
                     nodeArrayFlags |= node.transformFlags & ~536870912 /* HasComputedFlags */;
                 }
@@ -31303,8 +31306,8 @@ var ts;
         }
         function findConstructorDeclaration(node) {
             var members = node.members;
-            for (var _i = 0, members_1 = members; _i < members_1.length; _i++) {
-                var member = members_1[_i];
+            for (var _i = 0, members_2 = members; _i < members_2.length; _i++) {
+                var member = members_2[_i];
                 if (member.kind === 155 /* Constructor */ && ts.nodeIsPresent(member.body)) {
                     return member;
                 }
@@ -33210,7 +33213,7 @@ var ts;
             var definedInConstructor = false;
             var definedInMethod = false;
             var jsDocType;
-            var _loop_1 = function (declaration) {
+            var _loop_4 = function (declaration) {
                 var declarationInConstructor = false;
                 var expression = declaration.kind === 200 /* BinaryExpression */ ? declaration :
                     declaration.kind === 185 /* PropertyAccessExpression */ ? ts.cast(declaration.parent, ts.isBinaryExpression) :
@@ -33253,20 +33256,20 @@ var ts;
                         special === 2 /* ModuleExports */ &&
                         symbol.escapedName === "export=" /* ExportEquals */) {
                         var exportedType_1 = resolveStructuredTypeMembers(type_2);
-                        var members_2 = ts.createSymbolTable();
-                        ts.copyEntries(exportedType_1.members, members_2);
+                        var members_3 = ts.createSymbolTable();
+                        ts.copyEntries(exportedType_1.members, members_3);
                         symbol.exports.forEach(function (s, name) {
-                            if (members_2.has(name)) {
+                            if (members_3.has(name)) {
                                 var exportedMember = exportedType_1.members.get(name);
                                 var union = createSymbol(s.flags | exportedMember.flags, name);
                                 union.type = getUnionType([getTypeOfSymbol(s), getTypeOfSymbol(exportedMember)]);
-                                members_2.set(name, union);
+                                members_3.set(name, union);
                             }
                             else {
-                                members_2.set(name, s);
+                                members_3.set(name, s);
                             }
                         });
-                        type_2 = createAnonymousType(exportedType_1.symbol, members_2, exportedType_1.callSignatures, exportedType_1.constructSignatures, exportedType_1.stringIndexInfo, exportedType_1.numberIndexInfo);
+                        type_2 = createAnonymousType(exportedType_1.symbol, members_3, exportedType_1.callSignatures, exportedType_1.constructSignatures, exportedType_1.stringIndexInfo, exportedType_1.numberIndexInfo);
                     }
                     var anyedType = type_2;
                     if (isEmptyArrayLiteralType(type_2)) {
@@ -33283,7 +33286,7 @@ var ts;
             };
             for (var _i = 0, _a = symbol.declarations; _i < _a.length; _i++) {
                 var declaration = _a[_i];
-                var state_2 = _loop_1(declaration);
+                var state_2 = _loop_4(declaration);
                 if (typeof state_2 === "object")
                     return state_2.value;
             }
@@ -33752,8 +33755,8 @@ var ts;
         // The function allocates a new array if the input type parameter set is undefined, but otherwise it modifies the set
         // in-place and returns the same array.
         function appendTypeParameters(typeParameters, declarations) {
-            for (var _i = 0, declarations_1 = declarations; _i < declarations_1.length; _i++) {
-                var declaration = declarations_1[_i];
+            for (var _i = 0, declarations_2 = declarations; _i < declarations_2.length; _i++) {
+                var declaration = declarations_2[_i];
                 typeParameters = ts.appendIfUnique(typeParameters, getDeclaredTypeOfTypeParameter(getSymbolOfNode(declaration)));
             }
             return typeParameters;
@@ -34331,8 +34334,8 @@ var ts;
         // we check symbols to see if we can quickly conclude they are free of "this" references, thus needing no instantiation.
         function createInstantiatedSymbolTable(symbols, mapper, mappingThisOnly) {
             var result = ts.createSymbolTable();
-            for (var _i = 0, symbols_1 = symbols; _i < symbols_1.length; _i++) {
-                var symbol = symbols_1[_i];
+            for (var _i = 0, symbols_2 = symbols; _i < symbols_2.length; _i++) {
+                var symbol = symbols_2[_i];
                 result.set(symbol.escapedName, mappingThisOnly && isThisless(symbol) ? symbol : instantiateSymbol(symbol, mapper));
             }
             return result;
@@ -34482,9 +34485,9 @@ var ts;
                         // If we have an existing early-bound member, combine its declarations so that we can
                         // report an error at each declaration.
                         var declarations = earlySymbol ? ts.concatenate(earlySymbol.declarations, lateSymbol.declarations) : lateSymbol.declarations;
-                        var name_1 = ts.declarationNameToString(decl.name);
-                        ts.forEach(declarations, function (declaration) { return error(ts.getNameOfDeclaration(declaration) || declaration, ts.Diagnostics.Duplicate_declaration_0, name_1); });
-                        error(decl.name || decl, ts.Diagnostics.Duplicate_declaration_0, name_1);
+                        var name_2 = ts.declarationNameToString(decl.name);
+                        ts.forEach(declarations, function (declaration) { return error(ts.getNameOfDeclaration(declaration) || declaration, ts.Diagnostics.Duplicate_declaration_0, name_2); });
+                        error(decl.name || decl, ts.Diagnostics.Duplicate_declaration_0, name_2);
                         lateSymbol = createSymbol(0 /* None */, memberName, 1024 /* Late */);
                     }
                     lateSymbol.nameType = type;
@@ -34517,8 +34520,8 @@ var ts;
                     var decl = _a[_i];
                     var members = ts.getMembersOfDeclaration(decl);
                     if (members) {
-                        for (var _b = 0, members_3 = members; _b < members_3.length; _b++) {
-                            var member = members_3[_b];
+                        for (var _b = 0, members_4 = members; _b < members_4.length; _b++) {
+                            var member = members_4[_b];
                             if (isStatic === ts.hasStaticModifier(member) && hasLateBindableName(member)) {
                                 lateBindMember(symbol, earlySymbols, lateSymbols, member);
                             }
@@ -34794,7 +34797,7 @@ var ts;
             var numberIndexInfo;
             var types = type.types;
             var mixinCount = ts.countWhere(types, isMixinConstructorType);
-            var _loop_2 = function (i) {
+            var _loop_5 = function (i) {
                 var t = type.types[i];
                 // When an intersection type contains mixin constructor types, the construct signatures from
                 // those types are discarded and their return types are mixed into the return types of all
@@ -34817,7 +34820,7 @@ var ts;
                 numberIndexInfo = intersectIndexInfos(numberIndexInfo, getIndexInfoOfType(t, 1 /* Number */));
             };
             for (var i = 0; i < types.length; i++) {
-                _loop_2(i);
+                _loop_5(i);
             }
             setStructuredTypeMembers(type, emptySymbols, callSignatures, constructSignatures, stringIndexInfo, numberIndexInfo);
         }
@@ -36397,8 +36400,8 @@ var ts;
         function getTypeOfGlobalSymbol(symbol, arity) {
             function getTypeDeclaration(symbol) {
                 var declarations = symbol.declarations;
-                for (var _i = 0, declarations_2 = declarations; _i < declarations_2.length; _i++) {
-                    var declaration = declarations_2[_i];
+                for (var _i = 0, declarations_3 = declarations; _i < declarations_3.length; _i++) {
+                    var declaration = declarations_3[_i];
                     switch (declaration.kind) {
                         case 235 /* ClassDeclaration */:
                         case 236 /* InterfaceDeclaration */:
@@ -36859,7 +36862,7 @@ var ts;
             var unionType = types[unionIndex];
             var intersection = unionType.types;
             var i = types.length - 1;
-            var _loop_3 = function () {
+            var _loop_6 = function () {
                 var t = types[i];
                 if (t.flags & 67108864 /* UnionOfUnitTypes */) {
                     intersection = ts.filter(intersection, function (u) { return containsType(t.types, u); });
@@ -36868,7 +36871,7 @@ var ts;
                 i--;
             };
             while (i > unionIndex) {
-                _loop_3();
+                _loop_6();
             }
             if (intersection === unionType.types) {
                 return false;
@@ -38815,7 +38818,7 @@ var ts;
                         // check excess properties against discriminant type only, not the entire union
                         return hasExcessProperties(source, discriminant, /*discriminant*/ undefined, reportErrors);
                     }
-                    var _loop_4 = function (prop) {
+                    var _loop_7 = function (prop) {
                         if (!isKnownProperty(target, prop.escapedName, isComparingJsxAttributes)) {
                             if (reportErrors) {
                                 // We know *exactly* where things went wrong when comparing the types.
@@ -38854,7 +38857,7 @@ var ts;
                     };
                     for (var _i = 0, _a = getPropertiesOfObjectType(source); _i < _a.length; _i++) {
                         var prop = _a[_i];
-                        var state_3 = _loop_4(prop);
+                        var state_3 = _loop_7(prop);
                         if (typeof state_3 === "object")
                             return state_3.value;
                     }
@@ -39300,10 +39303,10 @@ var ts;
                 var modifiersRelated = relation === comparableRelation || (relation === identityRelation ? getMappedTypeModifiers(source) === getMappedTypeModifiers(target) :
                     getCombinedMappedTypeOptionality(source) <= getCombinedMappedTypeOptionality(target));
                 if (modifiersRelated) {
-                    var result_1;
-                    if (result_1 = isRelatedTo(getConstraintTypeFromMappedType(target), getConstraintTypeFromMappedType(source), reportErrors)) {
+                    var result_2;
+                    if (result_2 = isRelatedTo(getConstraintTypeFromMappedType(target), getConstraintTypeFromMappedType(source), reportErrors)) {
                         var mapper = createTypeMapper([getTypeParameterFromMappedType(source)], [getTypeParameterFromMappedType(target)]);
-                        return result_1 & isRelatedTo(instantiateType(getTemplateTypeFromMappedType(source), mapper), getTemplateTypeFromMappedType(target), reportErrors);
+                        return result_2 & isRelatedTo(instantiateType(getTemplateTypeFromMappedType(source), mapper), getTemplateTypeFromMappedType(target), reportErrors);
                     }
                 }
                 return 0 /* False */;
@@ -44630,7 +44633,7 @@ var ts;
                 // Assignability failure - check each prop individually, and if that fails, fall back on the bad error span
                 if (ts.length(openingLikeElement.attributes.properties)) {
                     var reportedError = false;
-                    var _loop_5 = function (prop) {
+                    var _loop_8 = function (prop) {
                         if (ts.isJsxSpreadAttribute(prop))
                             return "continue";
                         var name = ts.idText(prop.name);
@@ -44644,7 +44647,7 @@ var ts;
                     };
                     for (var _b = 0, _c = openingLikeElement.attributes.properties; _b < _c.length; _b++) {
                         var prop = _c[_b];
-                        _loop_5(prop);
+                        _loop_8(prop);
                     }
                     if (reportedError) {
                         return;
@@ -45577,13 +45580,13 @@ var ts;
         function getEffectiveCallArguments(node) {
             if (node.kind === 189 /* TaggedTemplateExpression */) {
                 var template = node.template;
-                var args_1 = [undefined]; // TODO: GH#18217
+                var args_4 = [undefined]; // TODO: GH#18217
                 if (template.kind === 202 /* TemplateExpression */) {
                     ts.forEach(template.templateSpans, function (span) {
-                        args_1.push(span.expression);
+                        args_4.push(span.expression);
                     });
                 }
-                return args_1;
+                return args_4;
             }
             else if (node.kind === 150 /* Decorator */) {
                 // For a decorator, we return undefined as we will determine
@@ -48995,8 +48998,8 @@ var ts;
             }
             var duplicateFunctionDeclaration = false;
             var multipleConstructorImplementation = false;
-            for (var _i = 0, declarations_3 = declarations; _i < declarations_3.length; _i++) {
-                var current = declarations_3[_i];
+            for (var _i = 0, declarations_4 = declarations; _i < declarations_4.length; _i++) {
+                var current = declarations_4[_i];
                 var node = current;
                 var inAmbientContext = node.flags & 4194304 /* Ambient */;
                 var inAmbientContextOrInterface = node.parent.kind === 236 /* InterfaceDeclaration */ || node.parent.kind === 166 /* TypeLiteral */ || inAmbientContext;
@@ -49165,10 +49168,10 @@ var ts;
                     case 243 /* ImportEqualsDeclaration */:
                     case 246 /* NamespaceImport */:
                     case 245 /* ImportClause */:
-                        var result_2 = 0 /* None */;
+                        var result_3 = 0 /* None */;
                         var target = resolveAlias(getSymbolOfNode(d));
-                        ts.forEach(target.declarations, function (d) { result_2 |= getDeclarationSpaces(d); });
-                        return result_2;
+                        ts.forEach(target.declarations, function (d) { result_3 |= getDeclarationSpaces(d); });
+                        return result_3;
                     case 232 /* VariableDeclaration */:
                     case 182 /* BindingElement */:
                     case 234 /* FunctionDeclaration */:
@@ -49965,8 +49968,8 @@ var ts;
                         : ts.createDiagnosticForNode(declarationList.parent.kind === 214 /* VariableStatement */ ? declarationList.parent : declarationList, ts.Diagnostics.All_variables_are_unused));
                 }
                 else {
-                    for (var _i = 0, declarations_4 = declarations; _i < declarations_4.length; _i++) {
-                        var decl = declarations_4[_i];
+                    for (var _i = 0, declarations_5 = declarations; _i < declarations_5.length; _i++) {
+                        var decl = declarations_5[_i];
                         addDiagnostic(0 /* Local */, ts.createDiagnosticForNode(decl, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, ts.idText(ts.cast(decl.name, ts.isIdentifier))));
                     }
                 }
@@ -51150,8 +51153,8 @@ var ts;
                 if (!areTypeParametersIdentical(declarations, type.localTypeParameters)) {
                     // Report an error on every conflicting declaration.
                     var name = symbolToString(symbol);
-                    for (var _i = 0, declarations_5 = declarations; _i < declarations_5.length; _i++) {
-                        var declaration = declarations_5[_i];
+                    for (var _i = 0, declarations_6 = declarations; _i < declarations_6.length; _i++) {
+                        var declaration = declarations_6[_i];
                         error(declaration.name, ts.Diagnostics.All_declarations_of_0_must_have_identical_type_parameters, name);
                     }
                 }
@@ -51160,8 +51163,8 @@ var ts;
         function areTypeParametersIdentical(declarations, targetParameters) {
             var maxTypeArgumentCount = ts.length(targetParameters);
             var minTypeArgumentCount = getMinTypeArgumentCount(targetParameters);
-            for (var _i = 0, declarations_6 = declarations; _i < declarations_6.length; _i++) {
-                var declaration = declarations_6[_i];
+            for (var _i = 0, declarations_7 = declarations; _i < declarations_7.length; _i++) {
+                var declaration = declarations_7[_i];
                 // If this declaration has too few or too many type parameters, we report an error
                 var sourceParameters = ts.getEffectiveTypeParameterDeclarations(declaration);
                 var numTypeParameters = sourceParameters.length;
@@ -51315,7 +51318,7 @@ var ts;
         function issueMemberSpecificError(node, typeWithThis, baseWithThis, broadDiag) {
             // iterate over all implemented properties and issue errors on each one which isn't compatible, rather than the class as a whole, if possible
             var issuedMemberError = false;
-            var _loop_6 = function (member) {
+            var _loop_9 = function (member) {
                 if (ts.hasStaticModifier(member)) {
                     return "continue";
                 }
@@ -51334,7 +51337,7 @@ var ts;
             };
             for (var _i = 0, _a = node.members; _i < _a.length; _i++) {
                 var member = _a[_i];
-                _loop_6(member);
+                _loop_9(member);
             }
             if (!issuedMemberError) {
                 // check again with diagnostics to generate a less-specific error
@@ -51619,12 +51622,12 @@ var ts;
             function evaluate(expr) {
                 switch (expr.kind) {
                     case 198 /* PrefixUnaryExpression */:
-                        var value_1 = evaluate(expr.operand);
-                        if (typeof value_1 === "number") {
+                        var value_2 = evaluate(expr.operand);
+                        if (typeof value_2 === "number") {
                             switch (expr.operator) {
-                                case 37 /* PlusToken */: return value_1;
-                                case 38 /* MinusToken */: return -value_1;
-                                case 52 /* TildeToken */: return ~value_1;
+                                case 37 /* PlusToken */: return value_2;
+                                case 38 /* MinusToken */: return -value_2;
+                                case 52 /* TildeToken */: return ~value_2;
                             }
                         }
                         break;
@@ -51763,8 +51766,8 @@ var ts;
         }
         function getFirstNonAmbientClassOrFunctionDeclaration(symbol) {
             var declarations = symbol.declarations;
-            for (var _i = 0, declarations_7 = declarations; _i < declarations_7.length; _i++) {
-                var declaration = declarations_7[_i];
+            for (var _i = 0, declarations_8 = declarations; _i < declarations_8.length; _i++) {
+                var declaration = declarations_8[_i];
                 if ((declaration.kind === 235 /* ClassDeclaration */ ||
                     (declaration.kind === 234 /* FunctionDeclaration */ && ts.nodeIsPresent(declaration.body))) &&
                     !(declaration.flags & 4194304 /* Ambient */)) {
@@ -52187,9 +52190,9 @@ var ts;
                     }
                 }
                 // Checks for export * conflicts
-                var exports = getExportsOfModule(moduleSymbol);
-                if (exports) {
-                    exports.forEach(function (_a, id) {
+                var exports_1 = getExportsOfModule(moduleSymbol);
+                if (exports_1) {
+                    exports_1.forEach(function (_a, id) {
                         var declarations = _a.declarations, flags = _a.flags;
                         if (id === "__export") {
                             return;
@@ -52206,8 +52209,8 @@ var ts;
                             return;
                         }
                         if (exportedDeclarationsCount > 1) {
-                            for (var _i = 0, declarations_8 = declarations; _i < declarations_8.length; _i++) {
-                                var declaration = declarations_8[_i];
+                            for (var _i = 0, declarations_9 = declarations; _i < declarations_9.length; _i++) {
+                                var declaration = declarations_9[_i];
                                 if (isNotOverload(declaration)) {
                                     diagnostics.add(ts.createDiagnosticForNode(declaration, ts.Diagnostics.Cannot_redeclare_exported_variable_0, ts.unescapeLeadingUnderscores(id)));
                                 }
@@ -54270,8 +54273,8 @@ var ts;
         }
         function checkGrammarForOmittedArgument(args) {
             if (args) {
-                for (var _i = 0, args_2 = args; _i < args_2.length; _i++) {
-                    var arg = args_2[_i];
+                for (var _i = 0, args_5 = args; _i < args_5.length; _i++) {
+                    var arg = args_5[_i];
                     if (arg.kind === 206 /* OmittedExpression */) {
                         return grammarErrorAtPos(arg, arg.pos, 0, ts.Diagnostics.Argument_expression_expected);
                     }
@@ -60242,8 +60245,8 @@ var ts;
         }
         var subtreeFlags = 0 /* None */;
         var nodeArrayFlags = 0 /* None */;
-        for (var _i = 0, nodes_2 = nodes; _i < nodes_2.length; _i++) {
-            var node = nodes_2[_i];
+        for (var _i = 0, nodes_3 = nodes; _i < nodes_3.length; _i++) {
+            var node = nodes_3[_i];
             subtreeFlags |= aggregateTransformFlagsForNode(node);
             nodeArrayFlags |= node.transformFlags & ~536870912 /* HasComputedFlags */;
         }
@@ -62308,8 +62311,8 @@ var ts;
         function generateClassElementDecorationExpressions(node, isStatic) {
             var members = getDecoratedClassElements(node, isStatic);
             var expressions;
-            for (var _i = 0, members_4 = members; _i < members_4.length; _i++) {
-                var member = members_4[_i];
+            for (var _i = 0, members_5 = members; _i < members_5.length; _i++) {
+                var member = members_5[_i];
                 var expression = generateClassElementDecorationExpression(node, member);
                 if (expression) {
                     if (!expressions) {
@@ -74851,8 +74854,8 @@ var ts;
                 return;
             }
             necessaryTypeRefernces = necessaryTypeRefernces || ts.createMap();
-            for (var _i = 0, typeReferenceDirectives_1 = typeReferenceDirectives; _i < typeReferenceDirectives_1.length; _i++) {
-                var ref = typeReferenceDirectives_1[_i];
+            for (var _i = 0, typeReferenceDirectives_2 = typeReferenceDirectives; _i < typeReferenceDirectives_2.length; _i++) {
+                var ref = typeReferenceDirectives_2[_i];
                 necessaryTypeRefernces.set(ref, true);
             }
         }
@@ -75760,7 +75763,7 @@ var ts;
             var prop = ts.createProperty(/*decorators*/ undefined, maskModifiers(node, /*mask*/ undefined, (!accessors.setAccessor) ? 64 /* Readonly */ : 0 /* None */), node.name, node.questionToken, ensureType(node, accessorType), /*initializer*/ undefined);
             var leadingsSyntheticCommentRanges = accessors.secondAccessor && ts.getLeadingCommentRangesOfNode(accessors.secondAccessor, currentSourceFile);
             if (leadingsSyntheticCommentRanges) {
-                var _loop_7 = function (range) {
+                var _loop_10 = function (range) {
                     if (range.kind === 3 /* MultiLineCommentTrivia */) {
                         var text = currentSourceFile.text.slice(range.pos + 2, range.end - 2);
                         var lines = text.split(/\r\n?|\n/g);
@@ -75774,7 +75777,7 @@ var ts;
                 };
                 for (var _i = 0, leadingsSyntheticCommentRanges_1 = leadingsSyntheticCommentRanges; _i < leadingsSyntheticCommentRanges_1.length; _i++) {
                     var range = leadingsSyntheticCommentRanges_1[_i];
-                    _loop_7(range);
+                    _loop_10(range);
                 }
             }
             return prop;
@@ -75983,8 +75986,8 @@ var ts;
             }
         };
         // Ensure the parse tree is clean before applying transformations
-        for (var _i = 0, nodes_3 = nodes; _i < nodes_3.length; _i++) {
-            var node = nodes_3[_i];
+        for (var _i = 0, nodes_4 = nodes; _i < nodes_4.length; _i++) {
+            var node = nodes_4[_i];
             ts.disposeEmitNodes(ts.getSourceFileOfNode(ts.getParseTreeNode(node)));
         }
         ts.performance.mark("beforeTransform");
@@ -76175,8 +76178,8 @@ var ts;
         function dispose() {
             if (state < 3 /* Disposed */) {
                 // Clean up emit nodes on parse tree
-                for (var _i = 0, nodes_4 = nodes; _i < nodes_4.length; _i++) {
-                    var node = nodes_4[_i];
+                for (var _i = 0, nodes_5 = nodes; _i < nodes_5.length; _i++) {
+                    var node = nodes_5[_i];
                     ts.disposeEmitNodes(ts.getSourceFileOfNode(ts.getParseTreeNode(node)));
                 }
                 // Release references to external entries for GC purposes.
@@ -79732,8 +79735,8 @@ var ts;
         function writeLines(text) {
             var lines = text.split(/\r\n?|\n/g);
             var indentation = ts.guessIndentation(lines);
-            for (var _a = 0, lines_1 = lines; _a < lines_1.length; _a++) {
-                var lineText = lines_1[_a];
+            for (var _a = 0, lines_2 = lines; _a < lines_2.length; _a++) {
+                var lineText = lines_2[_a];
                 var line = indentation ? lineText.slice(indentation) : lineText;
                 if (line.length) {
                     writeLine();
@@ -81261,13 +81264,13 @@ var ts;
                 // which per above occurred during the current program creation.
                 // Since we assume the filesystem does not change during program creation,
                 // it is safe to reuse resolutions from the earlier call.
-                var result_3 = [];
+                var result_4 = [];
                 for (var _i = 0, moduleNames_1 = moduleNames; _i < moduleNames_1.length; _i++) {
                     var moduleName = moduleNames_1[_i];
                     var resolvedModule = file.resolvedModules.get(moduleName);
-                    result_3.push(resolvedModule);
+                    result_4.push(resolvedModule);
                 }
-                return result_3;
+                return result_4;
             }
             // At this point, we know at least one of the following hold:
             // - file has local declarations for ambient modules
@@ -81965,8 +81968,8 @@ var ts;
                             }
                             break;
                     }
-                    for (var _b = 0, nodes_5 = nodes; _b < nodes_5.length; _b++) {
-                        var node = nodes_5[_b];
+                    for (var _b = 0, nodes_6 = nodes; _b < nodes_6.length; _b++) {
+                        var node = nodes_6[_b];
                         walk(node);
                     }
                 }
@@ -82623,14 +82626,14 @@ var ts;
             if (options.composite && rootNames.length < files.length) {
                 var normalizedRootNames = rootNames.map(function (r) { return ts.normalizePath(r).toLowerCase(); });
                 var sourceFiles = files.filter(function (f) { return !f.isDeclarationFile; }).map(function (f) { return ts.normalizePath(f.path).toLowerCase(); });
-                var _loop_8 = function (file) {
+                var _loop_11 = function (file) {
                     if (normalizedRootNames.every(function (r) { return r !== file; })) {
                         programDiagnostics.add(ts.createCompilerDiagnostic(ts.Diagnostics.File_0_is_not_in_project_file_list_Projects_must_list_all_files_or_use_an_include_pattern, file));
                     }
                 };
                 for (var _i = 0, sourceFiles_4 = sourceFiles; _i < sourceFiles_4.length; _i++) {
                     var file = sourceFiles_4[_i];
-                    _loop_8(file);
+                    _loop_11(file);
                 }
             }
             if (options.paths) {
@@ -84499,8 +84502,8 @@ var ts;
         function tryGetAnyFileFromPath(host, path) {
             // We check all js, `node` and `json` extensions in addition to TS, since node module resolution would also choose those over the directory
             var extensions = ts.getSupportedExtensions({ allowJs: true }, [{ extension: "node", isMixedContent: false }, { extension: "json", isMixedContent: false, scriptKind: 6 /* JSON */ }]);
-            for (var _i = 0, extensions_1 = extensions; _i < extensions_1.length; _i++) {
-                var e = extensions_1[_i];
+            for (var _i = 0, extensions_3 = extensions; _i < extensions_3.length; _i++) {
+                var e = extensions_3[_i];
                 var fullPath = path + e;
                 if (host.fileExists(fullPath)) { // TODO: GH#18217
                     return fullPath;
@@ -85398,7 +85401,6 @@ var ts;
             getKeys: getKeys
         };
     }
-    ts.createDependencyMapper = createDependencyMapper;
     function getOutputDeclarationFileName(inputFileName, configFile) {
         var relativePath = ts.getRelativePathFromDirectory(rootDirOfOptions(configFile.options, configFile.options.configFilePath), inputFileName, /*ignoreCase*/ true);
         var outputPath = ts.resolvePath(configFile.options.declarationDir || configFile.options.outDir || ts.getDirectoryPath(configFile.options.configFilePath), relativePath);
@@ -85524,8 +85526,8 @@ var ts;
         var clean = false;
         var watch = false;
         var projects = [];
-        for (var _i = 0, args_3 = args; _i < args_3.length; _i++) {
-            var arg = args_3[_i];
+        for (var _i = 0, args_6 = args; _i < args_6.length; _i++) {
+            var arg = args_6[_i];
             switch (arg.toLowerCase()) {
                 case "-v":
                 case "--verbose":
@@ -85549,23 +85551,28 @@ var ts;
                 case "--?":
                 case "-?":
                 case "--help":
-                    return ts.printHelp(buildOpts, "--build ");
+                    ts.printHelp(buildOpts, "--build ");
+                    return ts.ExitStatus.Success;
             }
             // Not a flag, parse as filename
             addProject(arg);
         }
         // Nonsensical combinations
         if (clean && force) {
-            return buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "force");
+            buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "force");
+            return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
         }
         if (clean && verbose) {
-            return buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "verbose");
+            buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "verbose");
+            return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
         }
         if (clean && watch) {
-            return buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "watch");
+            buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "watch");
+            return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
         }
         if (watch && dry) {
-            return buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "watch", "dry");
+            buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "watch", "dry");
+            return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
         }
         if (projects.length === 0) {
             // tsc -b invoked with no extra arguments; act as if invoked with "tsc -b ."
@@ -85573,14 +85580,13 @@ var ts;
         }
         var builder = createSolutionBuilder(compilerHost, buildHost, projects, { dry: dry, force: force, verbose: verbose }, system);
         if (clean) {
-            builder.cleanAllProjects();
-        }
-        else {
-            builder.buildAllProjects();
+            return builder.cleanAllProjects();
         }
         if (watch) {
-            return builder.startWatching();
+            builder.startWatching();
+            return undefined;
         }
+        return builder.buildAllProjects();
         function addProject(projectSpecification) {
             var fileName = ts.resolvePath(compilerHost.getCurrentDirectory(), projectSpecification);
             var refPath = ts.resolveProjectReferencePath(compilerHost, { path: fileName });
@@ -85628,7 +85634,7 @@ var ts;
                 // Everything is broken - we don't even know what to watch. Give up.
                 return;
             }
-            var _loop_9 = function (resolved) {
+            var _loop_12 = function (resolved) {
                 var cfg = configFileCache.parseConfigFile(resolved);
                 if (cfg) {
                     // Watch this file
@@ -85655,7 +85661,7 @@ var ts;
             };
             for (var _i = 0, _a = graph.buildQueue; _i < _a.length; _i++) {
                 var resolved = _a[_i];
-                _loop_9(resolved);
+                _loop_12(resolved);
             }
             function invalidateProjectAndScheduleBuilds(resolved) {
                 invalidateProject(resolved);
@@ -85836,9 +85842,11 @@ var ts;
                 }
             }
             var pseudoUpToDate = false;
+            var usesPrepend = false;
             if (project.projectReferences) {
                 for (var _c = 0, _d = project.projectReferences; _c < _d.length; _c++) {
                     var ref = _d[_c];
+                    usesPrepend = usesPrepend || !!(ref.prepend);
                     var resolvedRef = ts.resolveProjectReferencePath(compilerHost, ref);
                     var refStatus = getUpToDateStatus(configFileCache.parseConfigFile(resolvedRef));
                     // An upstream project is blocked
@@ -85888,6 +85896,9 @@ var ts;
                     newerInputFileName: newestInputFileName
                 };
             }
+            if (usesPrepend) {
+                pseudoUpToDate = false;
+            }
             // Up to date
             return {
                 type: pseudoUpToDate ? UpToDateStatusType.UpToDateWithUpstreamTypes : UpToDateStatusType.UpToDate,
@@ -86091,14 +86102,17 @@ var ts;
         function cleanAllProjects() {
             var resolvedNames = getAllProjectsInScope();
             if (resolvedNames === undefined) {
-                return buildHost.message(ts.Diagnostics.Skipping_clean_because_not_all_projects_could_be_located);
+                buildHost.message(ts.Diagnostics.Skipping_clean_because_not_all_projects_could_be_located);
+                return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
             }
             var filesToDelete = getFilesToClean(resolvedNames);
             if (filesToDelete === undefined) {
-                return buildHost.message(ts.Diagnostics.Skipping_clean_because_not_all_projects_could_be_located);
+                buildHost.message(ts.Diagnostics.Skipping_clean_because_not_all_projects_could_be_located);
+                return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
             }
             if (context.options.dry) {
-                return buildHost.message(ts.Diagnostics.A_non_dry_build_would_delete_the_following_files_Colon_0, filesToDelete.map(function (f) { return "\r\n * " + f; }).join(""));
+                buildHost.message(ts.Diagnostics.A_non_dry_build_would_delete_the_following_files_Colon_0, filesToDelete.map(function (f) { return "\r\n * " + f; }).join(""));
+                return ts.ExitStatus.Success;
             }
             // Do this check later to allow --clean --dry to function even if the host can't delete files
             if (!compilerHost.deleteFile) {
@@ -86108,6 +86122,7 @@ var ts;
                 var output = filesToDelete_1[_i];
                 compilerHost.deleteFile(output);
             }
+            return ts.ExitStatus.Success;
         }
         function resolveProjectName(name) {
             var fullPath = ts.resolvePath(compilerHost.getCurrentDirectory(), name);
@@ -86136,13 +86151,15 @@ var ts;
         function buildAllProjects() {
             var graph = getGlobalDependencyGraph();
             if (graph === undefined)
-                return;
+                return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
             var queue = graph.buildQueue;
             reportBuildQueue(graph);
+            var anyFailed = false;
             for (var _i = 0, queue_1 = queue; _i < queue_1.length; _i++) {
                 var next = queue_1[_i];
                 var proj = configFileCache.parseConfigFile(next);
                 if (proj === undefined) {
+                    anyFailed = true;
                     break;
                 }
                 var status = getUpToDateStatus(proj);
@@ -86170,8 +86187,10 @@ var ts;
                     // Do nothing
                     continue;
                 }
-                buildSingleProject(next);
+                var buildResult = buildSingleProject(next);
+                anyFailed = anyFailed || !!(buildResult & BuildResultFlags.AnyErrors);
             }
+            return anyFailed ? ts.ExitStatus.DiagnosticsPresent_OutputsSkipped : ts.ExitStatus.Success;
         }
         /**
          * Report the build ordering inferred from the current project graph if we're in verbose mode
@@ -86283,7 +86302,14 @@ var ts;
                 message: report,
                 errorDiagnostic: function (d) { return reportDiag_1(d); }
             };
-            return ts.performBuild(args.slice(1), ts.createCompilerHost({}), buildHost, ts.sys);
+            var result = ts.performBuild(args.slice(1), ts.createCompilerHost({}), buildHost, ts.sys);
+            // undefined = in watch mode, do not exit
+            if (result !== undefined) {
+                return ts.sys.exit(result);
+            }
+            else {
+                return;
+            }
         }
         var commandLine = ts.parseCommandLine(args);
         if (commandLine.options.build) {
diff --git a/lib/tsserver.js b/lib/tsserver.js
index e5585f845b6..47de11d43fd 100644
--- a/lib/tsserver.js
+++ b/lib/tsserver.js
@@ -13,6 +13,7 @@ See the Apache Version 2.0 License for specific language governing permissions
 and limitations under the License.
 ***************************************************************************** */
 
+
 "use strict";
 var __extends = (this && this.__extends) || (function () {
     var extendStatics = Object.setPrototypeOf ||
@@ -33,99 +34,18 @@ var __assign = (this && this.__assign) || Object.assign || function(t) {
     return t;
 };
 "use strict";
-/*@internal*/
-var ts;
-(function (ts) {
-    /** Gets a timestamp with (at least) ms resolution */
-    ts.timestamp = typeof performance !== "undefined" && performance.now ? function () { return performance.now(); } : Date.now ? Date.now : function () { return +(new Date()); };
-})(ts || (ts = {}));
-/*@internal*/
-/** Performance measurements for the compiler. */
-(function (ts) {
-    var performance;
-    (function (performance) {
-        // NOTE: cannot use ts.noop as core.ts loads after this
-        var profilerEvent = typeof onProfilerEvent === "function" && onProfilerEvent.profiler === true ? onProfilerEvent : function () { };
-        var enabled = false;
-        var profilerStart = 0;
-        var counts;
-        var marks;
-        var measures;
-        /**
-         * Marks a performance event.
-         *
-         * @param markName The name of the mark.
-         */
-        function mark(markName) {
-            if (enabled) {
-                marks.set(markName, ts.timestamp());
-                counts.set(markName, (counts.get(markName) || 0) + 1);
-                profilerEvent(markName);
-            }
-        }
-        performance.mark = mark;
-        /**
-         * Adds a performance measurement with the specified name.
-         *
-         * @param measureName The name of the performance measurement.
-         * @param startMarkName The name of the starting mark. If not supplied, the point at which the
-         *      profiler was enabled is used.
-         * @param endMarkName The name of the ending mark. If not supplied, the current timestamp is
-         *      used.
-         */
-        function measure(measureName, startMarkName, endMarkName) {
-            if (enabled) {
-                var end = endMarkName && marks.get(endMarkName) || ts.timestamp();
-                var start = startMarkName && marks.get(startMarkName) || profilerStart;
-                measures.set(measureName, (measures.get(measureName) || 0) + (end - start));
-            }
-        }
-        performance.measure = measure;
-        /**
-         * Gets the number of times a marker was encountered.
-         *
-         * @param markName The name of the mark.
-         */
-        function getCount(markName) {
-            return counts && counts.get(markName) || 0;
-        }
-        performance.getCount = getCount;
-        /**
-         * Gets the total duration of all measurements with the supplied name.
-         *
-         * @param measureName The name of the measure whose durations should be accumulated.
-         */
-        function getDuration(measureName) {
-            return measures && measures.get(measureName) || 0;
-        }
-        performance.getDuration = getDuration;
-        /**
-         * Iterate over each measure, performing some action
-         *
-         * @param cb The action to perform for each measure
-         */
-        function forEachMeasure(cb) {
-            measures.forEach(function (measure, key) {
-                cb(key, measure);
-            });
-        }
-        performance.forEachMeasure = forEachMeasure;
-        /** Enables (and resets) performance measurements for the compiler. */
-        function enable() {
-            counts = ts.createMap();
-            marks = ts.createMap();
-            measures = ts.createMap();
-            enabled = true;
-            profilerStart = ts.timestamp();
-        }
-        performance.enable = enable;
-        /** Disables performance measurements for the compiler. */
-        function disable() {
-            enabled = false;
-        }
-        performance.disable = disable;
-    })(performance = ts.performance || (ts.performance = {}));
-})(ts || (ts = {}));
+var __assign = (this && this.__assign) || Object.assign || function(t) {
+    for (var s, i = 1, n = arguments.length; i < n; i++) {
+        s = arguments[i];
+        for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
+            t[p] = s[p];
+    }
+    return t;
+};
+var __makeTemplateObject = (this && this.__makeTemplateObject) || function (cooked, raw) {
+    if (Object.defineProperty) { Object.defineProperty(cooked, "raw", { value: raw }); } else { cooked.raw = raw; }
+    return cooked;
+};
 var ts;
 (function (ts) {
     // WARNING: The script `configureNightly.ts` uses a regexp to parse out these values.
@@ -134,14 +54,17 @@ var ts;
     /** The version of the TypeScript compiler release */
     ts.version = ts.versionMajorMinor + ".0-dev";
 })(ts || (ts = {}));
-/* @internal */
 (function (ts) {
+    /* @internal */
     var Comparison;
     (function (Comparison) {
         Comparison[Comparison["LessThan"] = -1] = "LessThan";
         Comparison[Comparison["EqualTo"] = 0] = "EqualTo";
         Comparison[Comparison["GreaterThan"] = 1] = "GreaterThan";
     })(Comparison = ts.Comparison || (ts.Comparison = {}));
+})(ts || (ts = {}));
+/* @internal */
+(function (ts) {
     /** Create a MapLike with good performance. */
     function createDictionaryObject() {
         var map = Object.create(/*prototype*/ null); // tslint:disable-line:no-null-keyword
@@ -2003,16 +1926,99 @@ var ts;
     }
     ts.enumerateInsertsAndDeletes = enumerateInsertsAndDeletes;
 })(ts || (ts = {}));
-//# sourceMappingURL=core.js.map
-"use strict";
-var __assign = (this && this.__assign) || Object.assign || function(t) {
-    for (var s, i = 1, n = arguments.length; i < n; i++) {
-        s = arguments[i];
-        for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
-            t[p] = s[p];
-    }
-    return t;
-};
+/*@internal*/
+var ts;
+(function (ts) {
+    /** Gets a timestamp with (at least) ms resolution */
+    ts.timestamp = typeof performance !== "undefined" && performance.now ? function () { return performance.now(); } : Date.now ? Date.now : function () { return +(new Date()); };
+})(ts || (ts = {}));
+/*@internal*/
+/** Performance measurements for the compiler. */
+(function (ts) {
+    var performance;
+    (function (performance) {
+        // NOTE: cannot use ts.noop as core.ts loads after this
+        var profilerEvent = typeof onProfilerEvent === "function" && onProfilerEvent.profiler === true ? onProfilerEvent : function () { };
+        var enabled = false;
+        var profilerStart = 0;
+        var counts;
+        var marks;
+        var measures;
+        /**
+         * Marks a performance event.
+         *
+         * @param markName The name of the mark.
+         */
+        function mark(markName) {
+            if (enabled) {
+                marks.set(markName, ts.timestamp());
+                counts.set(markName, (counts.get(markName) || 0) + 1);
+                profilerEvent(markName);
+            }
+        }
+        performance.mark = mark;
+        /**
+         * Adds a performance measurement with the specified name.
+         *
+         * @param measureName The name of the performance measurement.
+         * @param startMarkName The name of the starting mark. If not supplied, the point at which the
+         *      profiler was enabled is used.
+         * @param endMarkName The name of the ending mark. If not supplied, the current timestamp is
+         *      used.
+         */
+        function measure(measureName, startMarkName, endMarkName) {
+            if (enabled) {
+                var end = endMarkName && marks.get(endMarkName) || ts.timestamp();
+                var start = startMarkName && marks.get(startMarkName) || profilerStart;
+                measures.set(measureName, (measures.get(measureName) || 0) + (end - start));
+            }
+        }
+        performance.measure = measure;
+        /**
+         * Gets the number of times a marker was encountered.
+         *
+         * @param markName The name of the mark.
+         */
+        function getCount(markName) {
+            return counts && counts.get(markName) || 0;
+        }
+        performance.getCount = getCount;
+        /**
+         * Gets the total duration of all measurements with the supplied name.
+         *
+         * @param measureName The name of the measure whose durations should be accumulated.
+         */
+        function getDuration(measureName) {
+            return measures && measures.get(measureName) || 0;
+        }
+        performance.getDuration = getDuration;
+        /**
+         * Iterate over each measure, performing some action
+         *
+         * @param cb The action to perform for each measure
+         */
+        function forEachMeasure(cb) {
+            measures.forEach(function (measure, key) {
+                cb(key, measure);
+            });
+        }
+        performance.forEachMeasure = forEachMeasure;
+        /** Enables (and resets) performance measurements for the compiler. */
+        function enable() {
+            counts = ts.createMap();
+            marks = ts.createMap();
+            measures = ts.createMap();
+            enabled = true;
+            profilerStart = ts.timestamp();
+        }
+        performance.enable = enable;
+        /** Disables performance measurements for the compiler. */
+        function disable() {
+            enabled = false;
+        }
+        performance.disable = disable;
+    })(performance = ts.performance || (ts.performance = {}));
+})(ts || (ts = {}));
 var ts;
 (function (ts) {
     // token > SyntaxKind.Identifier => token is a keyword
@@ -4289,8 +4295,8 @@ var ts;
                     var entries = _fs.readdirSync(path || ".").sort();
                     var files = [];
                     var directories = [];
-                    for (var _i = 0, entries_1 = entries; _i < entries_1.length; _i++) {
-                        var entry = entries_1[_i];
+                    for (var _i = 0, entries_2 = entries; _i < entries_2.length; _i++) {
+                        var entry = entries_2[_i];
                         // This is necessary because on some file system node fails to exclude
                         // "." and "..". See https://github.com/nodejs/node/issues/4002
                         if (entry === "." || entry === "..") {
@@ -4470,7 +4476,7 @@ var ts;
     }
 })(ts || (ts = {}));
 // <auto-generated />
-// generated from './diagnosticInformationMap.generated.ts' by 'src\parser'
+// generated from './diagnosticInformationMap.generated.ts' by 'src\compiler'
 /* @internal */
 var ts;
 (function (ts) {
@@ -7464,11 +7470,6 @@ var ts;
 /** Non-internal stuff goes here */
 var ts;
 (function (ts) {
-    ts.emptyArray = [];
-    function closeFileWatcher(watcher) {
-        watcher.close();
-    }
-    ts.closeFileWatcher = closeFileWatcher;
     function isExternalModuleNameRelative(moduleName) {
         // TypeScript 1.0 spec (April 2014): 11.2.1
         // An external module name is "relative" if the first term is "." or "..".
@@ -7480,20 +7481,10 @@ var ts;
         return ts.sortAndDeduplicate(diagnostics, ts.compareDiagnostics);
     }
     ts.sortAndDeduplicateDiagnostics = sortAndDeduplicateDiagnostics;
-    function toPath(fileName, basePath, getCanonicalFileName) {
-        var nonCanonicalizedPath = ts.isRootedDiskPath(fileName)
-            ? ts.normalizePath(fileName)
-            : ts.getNormalizedAbsolutePath(fileName, basePath);
-        return getCanonicalFileName(nonCanonicalizedPath);
-    }
-    ts.toPath = toPath;
-    function hasEntries(map) {
-        return !!map && !!map.size;
-    }
-    ts.hasEntries = hasEntries;
 })(ts || (ts = {}));
 /* @internal */
 (function (ts) {
+    ts.emptyArray = [];
     ts.resolvingEmptyArray = [];
     ts.emptyMap = ts.createMap();
     ts.emptyUnderscoreEscapedMap = ts.emptyMap;
@@ -7516,6 +7507,10 @@ var ts;
         return new ts.MapCtr();
     }
     ts.createUnderscoreEscapedMap = createUnderscoreEscapedMap;
+    function hasEntries(map) {
+        return !!map && !!map.size;
+    }
+    ts.hasEntries = hasEntries;
     function createSymbolTable(symbols) {
         var result = ts.createMap();
         if (symbols) {
@@ -7562,6 +7557,13 @@ var ts;
             reportPrivateInBaseOfClassExpression: ts.noop,
         };
     }
+    function toPath(fileName, basePath, getCanonicalFileName) {
+        var nonCanonicalizedPath = ts.isRootedDiskPath(fileName)
+            ? ts.normalizePath(fileName)
+            : ts.getNormalizedAbsolutePath(fileName, basePath);
+        return getCanonicalFileName(nonCanonicalizedPath);
+    }
+    ts.toPath = toPath;
     function changesAffectModuleResolution(oldOptions, newOptions) {
         return !oldOptions ||
             (oldOptions.module !== newOptions.module) ||
@@ -10391,7 +10393,7 @@ var ts;
      */
     function getExternalModuleNameFromPath(host, fileName, referencePath) {
         var getCanonicalFileName = function (f) { return host.getCanonicalFileName(f); };
-        var dir = ts.toPath(referencePath ? ts.getDirectoryPath(referencePath) : host.getCommonSourceDirectory(), host.getCurrentDirectory(), getCanonicalFileName);
+        var dir = toPath(referencePath ? ts.getDirectoryPath(referencePath) : host.getCommonSourceDirectory(), host.getCurrentDirectory(), getCanonicalFileName);
         var filePath = ts.getNormalizedAbsolutePath(fileName, host.getCurrentDirectory());
         var relativePath = ts.getRelativePathToDirectoryOrUrl(dir, filePath, dir, getCanonicalFileName, /*isAbsolutePathAnUrl*/ false);
         var extensionless = ts.removeFileExtension(relativePath);
@@ -11299,6 +11301,10 @@ var ts;
         return options.watch && options.hasOwnProperty("watch");
     }
     ts.isWatchSet = isWatchSet;
+    function closeFileWatcher(watcher) {
+        watcher.close();
+    }
+    ts.closeFileWatcher = closeFileWatcher;
     function getCheckFlags(symbol) {
         return symbol.flags & 33554432 /* Transient */ ? symbol.checkFlags : 0;
     }
@@ -13721,6 +13727,9 @@ var ts;
         return node.kind === 9 /* StringLiteral */ || node.kind === 13 /* NoSubstitutionTemplateLiteral */;
     }
     ts.isStringLiteralLike = isStringLiteralLike;
+})(ts || (ts = {}));
+/* @internal */
+(function (ts) {
     /** @internal */
     function isNamedImportsOrExports(node) {
         return node.kind === 247 /* NamedImports */ || node.kind === 251 /* NamedExports */;
@@ -13737,7 +13746,7 @@ var ts;
     }
     function Type(checker, flags) {
         this.flags = flags;
-        if (Debug.isDebugging) {
+        if (ts.Debug.isDebugging) {
             this.checker = checker;
         }
     }
@@ -13768,9 +13777,10 @@ var ts;
         getSignatureConstructor: function () { return Signature; },
         getSourceMapSourceConstructor: function () { return SourceMapSource; },
     };
+    /* @internal */
     function formatStringFromArgs(text, args, baseIndex) {
         if (baseIndex === void 0) { baseIndex = 0; }
-        return text.replace(/{(\d+)}/g, function (_match, index) { return Debug.assertDefined(args[+index + baseIndex]); });
+        return text.replace(/{(\d+)}/g, function (_match, index) { return ts.Debug.assertDefined(args[+index + baseIndex]); });
     }
     ts.formatStringFromArgs = formatStringFromArgs;
     function getLocaleSpecificMessage(message) {
@@ -13778,11 +13788,11 @@ var ts;
     }
     ts.getLocaleSpecificMessage = getLocaleSpecificMessage;
     function createFileDiagnostic(file, start, length, message) {
-        Debug.assertGreaterThanOrEqual(start, 0);
-        Debug.assertGreaterThanOrEqual(length, 0);
+        ts.Debug.assertGreaterThanOrEqual(start, 0);
+        ts.Debug.assertGreaterThanOrEqual(length, 0);
         if (file) {
-            Debug.assertLessThanOrEqual(start, file.text.length);
-            Debug.assertLessThanOrEqual(start + length, file.text.length);
+            ts.Debug.assertLessThanOrEqual(start, file.text.length);
+            ts.Debug.assertLessThanOrEqual(start + length, file.text.length);
         }
         var text = getLocaleSpecificMessage(message);
         if (arguments.length > 4) {
@@ -13824,6 +13834,7 @@ var ts;
         };
     }
     ts.createCompilerDiagnostic = createCompilerDiagnostic;
+    /* @internal */
     function createCompilerDiagnosticFromMessageChain(chain) {
         return {
             file: undefined,
@@ -13860,6 +13871,7 @@ var ts;
     function getDiagnosticFilePath(diagnostic) {
         return diagnostic.file ? diagnostic.file.path : undefined;
     }
+    /* @internal */
     function compareDiagnostics(d1, d2) {
         return ts.compareStringsCaseSensitive(getDiagnosticFilePath(d1), getDiagnosticFilePath(d2)) ||
             ts.compareValues(d1.start, d2.start) ||
@@ -14074,7 +14086,7 @@ var ts;
     ts.getRootLength = getRootLength;
     // TODO(rbuckton): replace references with `resolvePath`
     function normalizePath(path) {
-        return resolvePath(path);
+        return ts.resolvePath(path);
     }
     ts.normalizePath = normalizePath;
     function normalizePathAndParts(path) {
@@ -14082,7 +14094,7 @@ var ts;
         var _a = reducePathComponents(getPathComponents(path)), root = _a[0], parts = _a.slice(1);
         if (parts.length) {
             var joinedParts = root + parts.join(ts.directorySeparator);
-            return { path: hasTrailingDirectorySeparator(path) ? ensureTrailingDirectorySeparator(joinedParts) : joinedParts, parts: parts };
+            return { path: ts.hasTrailingDirectorySeparator(path) ? ts.ensureTrailingDirectorySeparator(joinedParts) : joinedParts, parts: parts };
         }
         else {
             return { path: root, parts: parts };
@@ -14097,7 +14109,7 @@ var ts;
             return path;
         // return the leading portion of the path up to the last (non-terminal) directory separator
         // but not including any trailing directory separator.
-        path = removeTrailingDirectorySeparator(path);
+        path = ts.removeTrailingDirectorySeparator(path);
         return path.slice(0, Math.max(rootLength, path.lastIndexOf(ts.directorySeparator)));
     }
     ts.getDirectoryPath = getDirectoryPath;
@@ -14125,10 +14137,11 @@ var ts;
         return rootLength > 0 && rootLength === path.length;
     }
     ts.isDiskPathRoot = isDiskPathRoot;
+    /* @internal */
     function convertToRelativePath(absoluteOrRelativePath, basePath, getCanonicalFileName) {
         return !isRootedDiskPath(absoluteOrRelativePath)
             ? absoluteOrRelativePath
-            : getRelativePathToDirectoryOrUrl(basePath, absoluteOrRelativePath, basePath, getCanonicalFileName, /*isAbsolutePathAnUrl*/ false);
+            : ts.getRelativePathToDirectoryOrUrl(basePath, absoluteOrRelativePath, basePath, getCanonicalFileName, /*isAbsolutePathAnUrl*/ false);
     }
     ts.convertToRelativePath = convertToRelativePath;
     function pathComponents(path, rootLength) {
@@ -14146,7 +14159,7 @@ var ts;
      */
     function getPathComponents(path, currentDirectory) {
         if (currentDirectory === void 0) { currentDirectory = ""; }
-        path = combinePaths(currentDirectory, path);
+        path = ts.combinePaths(currentDirectory, path);
         var rootLength = getRootLength(path);
         return pathComponents(path, rootLength);
     }
@@ -14201,15 +14214,18 @@ var ts;
     function getPathFromPathComponents(pathComponents) {
         if (pathComponents.length === 0)
             return "";
-        var root = pathComponents[0] && ensureTrailingDirectorySeparator(pathComponents[0]);
+        var root = pathComponents[0] && ts.ensureTrailingDirectorySeparator(pathComponents[0]);
         if (pathComponents.length === 1)
             return root;
         return root + pathComponents.slice(1).join(ts.directorySeparator);
     }
     ts.getPathFromPathComponents = getPathFromPathComponents;
+})(ts || (ts = {}));
+/* @internal */
+(function (ts) {
     function getPathComponentsRelativeTo(from, to, stringEqualityComparer, getCanonicalFileName) {
-        var fromComponents = reducePathComponents(getPathComponents(from));
-        var toComponents = reducePathComponents(getPathComponents(to));
+        var fromComponents = ts.reducePathComponents(ts.getPathComponents(from));
+        var toComponents = ts.reducePathComponents(ts.getPathComponents(to));
         var start;
         for (start = 0; start < fromComponents.length && start < toComponents.length; start++) {
             var fromComponent = getCanonicalFileName(fromComponents[start]);
@@ -14228,26 +14244,27 @@ var ts;
         }
         return [""].concat(relative, components);
     }
+    ts.getPathComponentsRelativeTo = getPathComponentsRelativeTo;
     function getRelativePathFromFile(from, to, getCanonicalFileName) {
-        return ensurePathIsNonModuleName(getRelativePathFromDirectory(getDirectoryPath(from), to, getCanonicalFileName));
+        return ensurePathIsNonModuleName(getRelativePathFromDirectory(ts.getDirectoryPath(from), to, getCanonicalFileName));
     }
     ts.getRelativePathFromFile = getRelativePathFromFile;
     function getRelativePathFromDirectory(fromDirectory, to, getCanonicalFileNameOrIgnoreCase) {
-        Debug.assert((getRootLength(fromDirectory) > 0) === (getRootLength(to) > 0), "Paths must either both be absolute or both be relative");
+        Debug.assert((ts.getRootLength(fromDirectory) > 0) === (ts.getRootLength(to) > 0), "Paths must either both be absolute or both be relative");
         var getCanonicalFileName = typeof getCanonicalFileNameOrIgnoreCase === "function" ? getCanonicalFileNameOrIgnoreCase : ts.identity;
         var ignoreCase = typeof getCanonicalFileNameOrIgnoreCase === "boolean" ? getCanonicalFileNameOrIgnoreCase : false;
         var pathComponents = getPathComponentsRelativeTo(fromDirectory, to, ignoreCase ? ts.equateStringsCaseInsensitive : ts.equateStringsCaseSensitive, getCanonicalFileName);
-        return getPathFromPathComponents(pathComponents);
+        return ts.getPathFromPathComponents(pathComponents);
     }
     ts.getRelativePathFromDirectory = getRelativePathFromDirectory;
     function getRelativePathToDirectoryOrUrl(directoryPathOrUrl, relativeOrAbsolutePath, currentDirectory, getCanonicalFileName, isAbsolutePathAnUrl) {
         var pathComponents = getPathComponentsRelativeTo(resolvePath(currentDirectory, directoryPathOrUrl), resolvePath(currentDirectory, relativeOrAbsolutePath), ts.equateStringsCaseSensitive, getCanonicalFileName);
         var firstComponent = pathComponents[0];
-        if (isAbsolutePathAnUrl && isRootedDiskPath(firstComponent)) {
+        if (isAbsolutePathAnUrl && ts.isRootedDiskPath(firstComponent)) {
             var prefix = firstComponent.charAt(0) === ts.directorySeparator ? "file://" : "file:///";
             pathComponents[0] = prefix + firstComponent;
         }
-        return getPathFromPathComponents(pathComponents);
+        return ts.getPathFromPathComponents(pathComponents);
     }
     ts.getRelativePathToDirectoryOrUrl = getRelativePathToDirectoryOrUrl;
     /**
@@ -14255,19 +14272,19 @@ var ts;
      * with `./` or `../`) so as not to be confused with an unprefixed module name.
      */
     function ensurePathIsNonModuleName(path) {
-        return getRootLength(path) === 0 && !pathIsRelative(path) ? "./" + path : path;
+        return ts.getRootLength(path) === 0 && !ts.pathIsRelative(path) ? "./" + path : path;
     }
     ts.ensurePathIsNonModuleName = ensurePathIsNonModuleName;
     function getBaseFileName(path, extensions, ignoreCase) {
-        path = normalizeSlashes(path);
+        path = ts.normalizeSlashes(path);
         // if the path provided is itself the root, then it has not file name.
-        var rootLength = getRootLength(path);
+        var rootLength = ts.getRootLength(path);
         if (rootLength === path.length)
             return "";
         // return the trailing portion of the path starting after the last (non-terminal) directory
         // separator but not including any trailing directory separator.
         path = removeTrailingDirectorySeparator(path);
-        var name = path.slice(Math.max(getRootLength(path), path.lastIndexOf(ts.directorySeparator) + 1));
+        var name = path.slice(Math.max(ts.getRootLength(path), path.lastIndexOf(ts.directorySeparator) + 1));
         var extension = extensions !== undefined && ignoreCase !== undefined ? getAnyExtensionFromPath(name, extensions, ignoreCase) : undefined;
         return extension ? name.slice(0, name.length - extension.length) : name;
     }
@@ -14281,13 +14298,13 @@ var ts;
             paths[_i - 1] = arguments[_i];
         }
         if (path)
-            path = normalizeSlashes(path);
+            path = ts.normalizeSlashes(path);
         for (var _a = 0, paths_1 = paths; _a < paths_1.length; _a++) {
             var relativePath = paths_1[_a];
             if (!relativePath)
                 continue;
-            relativePath = normalizeSlashes(relativePath);
-            if (!path || getRootLength(relativePath) !== 0) {
+            relativePath = ts.normalizeSlashes(relativePath);
+            if (!path || ts.getRootLength(relativePath) !== 0) {
                 path = relativePath;
             }
             else {
@@ -14306,8 +14323,8 @@ var ts;
         for (var _i = 1; _i < arguments.length; _i++) {
             paths[_i - 1] = arguments[_i];
         }
-        var combined = ts.some(paths) ? combinePaths.apply(void 0, [path].concat(paths)) : normalizeSlashes(path);
-        var normalized = getPathFromPathComponents(reducePathComponents(getPathComponents(combined)));
+        var combined = ts.some(paths) ? combinePaths.apply(void 0, [path].concat(paths)) : ts.normalizeSlashes(path);
+        var normalized = ts.getPathFromPathComponents(ts.reducePathComponents(ts.getPathComponents(combined)));
         return normalized && hasTrailingDirectorySeparator(combined) ? ensureTrailingDirectorySeparator(normalized) : normalized;
     }
     ts.resolvePath = resolvePath;
@@ -14342,8 +14359,8 @@ var ts;
             return -1 /* LessThan */;
         if (b === undefined)
             return 1 /* GreaterThan */;
-        var aComponents = reducePathComponents(getPathComponents(a));
-        var bComponents = reducePathComponents(getPathComponents(b));
+        var aComponents = ts.reducePathComponents(ts.getPathComponents(a));
+        var bComponents = ts.reducePathComponents(ts.getPathComponents(b));
         var sharedLength = Math.min(aComponents.length, bComponents.length);
         for (var i = 0; i < sharedLength; i++) {
             var stringComparer = i === 0 ? ts.compareStringsCaseInsensitive : componentComparer;
@@ -14391,8 +14408,8 @@ var ts;
             return false;
         if (parent === child)
             return true;
-        var parentComponents = reducePathComponents(getPathComponents(parent));
-        var childComponents = reducePathComponents(getPathComponents(child));
+        var parentComponents = ts.reducePathComponents(ts.getPathComponents(parent));
+        var childComponents = ts.reducePathComponents(ts.getPathComponents(child));
         if (childComponents.length < parentComponents.length) {
             return false;
         }
@@ -14495,7 +14512,7 @@ var ts;
         var singleAsteriskRegexFragment = _a.singleAsteriskRegexFragment, doubleAsteriskRegexFragment = _a.doubleAsteriskRegexFragment, replaceWildcardCharacter = _a.replaceWildcardCharacter;
         var subpattern = "";
         var hasWrittenComponent = false;
-        var components = getNormalizedPathComponents(spec, basePath);
+        var components = ts.getNormalizedPathComponents(spec, basePath);
         var lastComponent = ts.last(components);
         if (usage !== "exclude" && lastComponent === "**") {
             return undefined;
@@ -14562,8 +14579,8 @@ var ts;
     }
     /** @param path directory of the tsconfig.json */
     function getFileMatcherPatterns(path, excludes, includes, useCaseSensitiveFileNames, currentDirectory) {
-        path = normalizePath(path);
-        currentDirectory = normalizePath(currentDirectory);
+        path = ts.normalizePath(path);
+        currentDirectory = ts.normalizePath(currentDirectory);
         var absolutePath = combinePaths(currentDirectory, path);
         return {
             includeFilePatterns: ts.map(getRegularExpressionsForWildcards(includes, absolutePath, "files"), function (pattern) { return "^" + pattern + "$"; }),
@@ -14580,8 +14597,8 @@ var ts;
     ts.getRegexFromPattern = getRegexFromPattern;
     /** @param path directory of the tsconfig.json */
     function matchFiles(path, extensions, excludes, includes, useCaseSensitiveFileNames, currentDirectory, depth, getFileSystemEntries) {
-        path = normalizePath(path);
-        currentDirectory = normalizePath(currentDirectory);
+        path = ts.normalizePath(path);
+        currentDirectory = ts.normalizePath(currentDirectory);
         var patterns = getFileMatcherPatterns(path, excludes, includes, useCaseSensitiveFileNames, currentDirectory);
         var includeFileRegexes = patterns.includeFilePatterns && patterns.includeFilePatterns.map(function (pattern) { return getRegexFromPattern(pattern, useCaseSensitiveFileNames); });
         var includeDirectoryRegex = patterns.includeDirectoryPattern && getRegexFromPattern(patterns.includeDirectoryPattern, useCaseSensitiveFileNames);
@@ -14648,7 +14665,7 @@ var ts;
                 var include = includes_1[_i];
                 // We also need to check the relative paths by converting them to absolute and normalizing
                 // in case they escape the base path (e.g "..\somedirectory")
-                var absolute = isRootedDiskPath(include) ? include : normalizePath(combinePaths(path, include));
+                var absolute = ts.isRootedDiskPath(include) ? include : ts.normalizePath(combinePaths(path, include));
                 // Append the literal and canonical candidate base paths.
                 includeBasePaths.push(getIncludeBasePath(absolute));
             }
@@ -14674,7 +14691,7 @@ var ts;
             // No "*" or "?" in the path
             return !hasExtension(absolute)
                 ? absolute
-                : removeTrailingDirectorySeparator(getDirectoryPath(absolute));
+                : removeTrailingDirectorySeparator(ts.getDirectoryPath(absolute));
         }
         return absolute.substring(0, absolute.lastIndexOf(ts.directorySeparator, wildcardOffset));
     }
@@ -14851,7 +14868,7 @@ var ts;
     })(Debug = ts.Debug || (ts.Debug = {}));
     function tryParsePattern(pattern) {
         // This should be verified outside of here and a proper error thrown.
-        Debug.assert(hasZeroOrOneAsteriskCharacter(pattern));
+        Debug.assert(ts.hasZeroOrOneAsteriskCharacter(pattern));
         var indexOfStar = pattern.indexOf("*");
         return indexOfStar === -1 ? undefined : {
             prefix: pattern.substr(0, indexOfStar),
@@ -14894,8 +14911,8 @@ var ts;
     function getAnyExtensionFromPathWorker(path, extensions, stringEqualityComparer) {
         if (typeof extensions === "string")
             extensions = [extensions];
-        for (var _i = 0, extensions_1 = extensions; _i < extensions_1.length; _i++) {
-            var extension = extensions_1[_i];
+        for (var _i = 0, extensions_2 = extensions; _i < extensions_2.length; _i++) {
+            var extension = extensions_2[_i];
             if (!ts.startsWith(extension, "."))
                 extension = "." + extension;
             if (path.length >= extension.length && path.charAt(path.length - extension.length) === ".") {
@@ -21368,8 +21385,8 @@ var ts;
                 array._children = undefined;
                 array.pos += delta;
                 array.end += delta;
-                for (var _i = 0, array_1 = array; _i < array_1.length; _i++) {
-                    var node = array_1[_i];
+                for (var _i = 0, array_8 = array; _i < array_8.length; _i++) {
+                    var node = array_8[_i];
                     visitNode(node);
                 }
             }
@@ -21519,8 +21536,8 @@ var ts;
                     array._children = undefined;
                     // Adjust the pos or end (or both) of the intersecting array accordingly.
                     adjustIntersectingElement(array, changeStart, changeRangeOldEnd, changeRangeNewEnd, delta);
-                    for (var _i = 0, array_2 = array; _i < array_2.length; _i++) {
-                        var node = array_2[_i];
+                    for (var _i = 0, array_9 = array; _i < array_9.length; _i++) {
+                        var node = array_9[_i];
                         visitNode(node);
                     }
                     return;
@@ -25356,20 +25373,6 @@ var ts;
         return value !== undefined ? { value: value } : undefined;
     }
 })(ts || (ts = {}));
-//# sourceMappingURL=parser.js.map
-"use strict";
-var __assign = (this && this.__assign) || Object.assign || function(t) {
-    for (var s, i = 1, n = arguments.length; i < n; i++) {
-        s = arguments[i];
-        for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
-            t[p] = s[p];
-    }
-    return t;
-};
-var __makeTemplateObject = (this && this.__makeTemplateObject) || function (cooked, raw) {
-    if (Object.defineProperty) { Object.defineProperty(cooked, "raw", { value: raw }); } else { cooked.raw = raw; }
-    return cooked;
-};
 /* @internal */
 var ts;
 (function (ts) {
@@ -25930,8 +25933,8 @@ var ts;
                 var savedSubtreeTransformFlags = subtreeTransformFlags;
                 subtreeTransformFlags = 0 /* None */;
                 var nodeArrayFlags = 0 /* None */;
-                for (var _i = 0, nodes_1 = nodes; _i < nodes_1.length; _i++) {
-                    var node = nodes_1[_i];
+                for (var _i = 0, nodes_2 = nodes; _i < nodes_2.length; _i++) {
+                    var node = nodes_2[_i];
                     bindFunction(node);
                     nodeArrayFlags |= node.transformFlags & ~536870912 /* HasComputedFlags */;
                 }
@@ -31322,8 +31325,8 @@ var ts;
         }
         function findConstructorDeclaration(node) {
             var members = node.members;
-            for (var _i = 0, members_1 = members; _i < members_1.length; _i++) {
-                var member = members_1[_i];
+            for (var _i = 0, members_2 = members; _i < members_2.length; _i++) {
+                var member = members_2[_i];
                 if (member.kind === 155 /* Constructor */ && ts.nodeIsPresent(member.body)) {
                     return member;
                 }
@@ -33229,7 +33232,7 @@ var ts;
             var definedInConstructor = false;
             var definedInMethod = false;
             var jsDocType;
-            var _loop_1 = function (declaration) {
+            var _loop_4 = function (declaration) {
                 var declarationInConstructor = false;
                 var expression = declaration.kind === 200 /* BinaryExpression */ ? declaration :
                     declaration.kind === 185 /* PropertyAccessExpression */ ? ts.cast(declaration.parent, ts.isBinaryExpression) :
@@ -33272,20 +33275,20 @@ var ts;
                         special === 2 /* ModuleExports */ &&
                         symbol.escapedName === "export=" /* ExportEquals */) {
                         var exportedType_1 = resolveStructuredTypeMembers(type_2);
-                        var members_2 = ts.createSymbolTable();
-                        ts.copyEntries(exportedType_1.members, members_2);
+                        var members_3 = ts.createSymbolTable();
+                        ts.copyEntries(exportedType_1.members, members_3);
                         symbol.exports.forEach(function (s, name) {
-                            if (members_2.has(name)) {
+                            if (members_3.has(name)) {
                                 var exportedMember = exportedType_1.members.get(name);
                                 var union = createSymbol(s.flags | exportedMember.flags, name);
                                 union.type = getUnionType([getTypeOfSymbol(s), getTypeOfSymbol(exportedMember)]);
-                                members_2.set(name, union);
+                                members_3.set(name, union);
                             }
                             else {
-                                members_2.set(name, s);
+                                members_3.set(name, s);
                             }
                         });
-                        type_2 = createAnonymousType(exportedType_1.symbol, members_2, exportedType_1.callSignatures, exportedType_1.constructSignatures, exportedType_1.stringIndexInfo, exportedType_1.numberIndexInfo);
+                        type_2 = createAnonymousType(exportedType_1.symbol, members_3, exportedType_1.callSignatures, exportedType_1.constructSignatures, exportedType_1.stringIndexInfo, exportedType_1.numberIndexInfo);
                     }
                     var anyedType = type_2;
                     if (isEmptyArrayLiteralType(type_2)) {
@@ -33302,7 +33305,7 @@ var ts;
             };
             for (var _i = 0, _a = symbol.declarations; _i < _a.length; _i++) {
                 var declaration = _a[_i];
-                var state_2 = _loop_1(declaration);
+                var state_2 = _loop_4(declaration);
                 if (typeof state_2 === "object")
                     return state_2.value;
             }
@@ -33771,8 +33774,8 @@ var ts;
         // The function allocates a new array if the input type parameter set is undefined, but otherwise it modifies the set
         // in-place and returns the same array.
         function appendTypeParameters(typeParameters, declarations) {
-            for (var _i = 0, declarations_1 = declarations; _i < declarations_1.length; _i++) {
-                var declaration = declarations_1[_i];
+            for (var _i = 0, declarations_2 = declarations; _i < declarations_2.length; _i++) {
+                var declaration = declarations_2[_i];
                 typeParameters = ts.appendIfUnique(typeParameters, getDeclaredTypeOfTypeParameter(getSymbolOfNode(declaration)));
             }
             return typeParameters;
@@ -34350,8 +34353,8 @@ var ts;
         // we check symbols to see if we can quickly conclude they are free of "this" references, thus needing no instantiation.
         function createInstantiatedSymbolTable(symbols, mapper, mappingThisOnly) {
             var result = ts.createSymbolTable();
-            for (var _i = 0, symbols_1 = symbols; _i < symbols_1.length; _i++) {
-                var symbol = symbols_1[_i];
+            for (var _i = 0, symbols_2 = symbols; _i < symbols_2.length; _i++) {
+                var symbol = symbols_2[_i];
                 result.set(symbol.escapedName, mappingThisOnly && isThisless(symbol) ? symbol : instantiateSymbol(symbol, mapper));
             }
             return result;
@@ -34501,9 +34504,9 @@ var ts;
                         // If we have an existing early-bound member, combine its declarations so that we can
                         // report an error at each declaration.
                         var declarations = earlySymbol ? ts.concatenate(earlySymbol.declarations, lateSymbol.declarations) : lateSymbol.declarations;
-                        var name_1 = ts.declarationNameToString(decl.name);
-                        ts.forEach(declarations, function (declaration) { return error(ts.getNameOfDeclaration(declaration) || declaration, ts.Diagnostics.Duplicate_declaration_0, name_1); });
-                        error(decl.name || decl, ts.Diagnostics.Duplicate_declaration_0, name_1);
+                        var name_2 = ts.declarationNameToString(decl.name);
+                        ts.forEach(declarations, function (declaration) { return error(ts.getNameOfDeclaration(declaration) || declaration, ts.Diagnostics.Duplicate_declaration_0, name_2); });
+                        error(decl.name || decl, ts.Diagnostics.Duplicate_declaration_0, name_2);
                         lateSymbol = createSymbol(0 /* None */, memberName, 1024 /* Late */);
                     }
                     lateSymbol.nameType = type;
@@ -34536,8 +34539,8 @@ var ts;
                     var decl = _a[_i];
                     var members = ts.getMembersOfDeclaration(decl);
                     if (members) {
-                        for (var _b = 0, members_3 = members; _b < members_3.length; _b++) {
-                            var member = members_3[_b];
+                        for (var _b = 0, members_4 = members; _b < members_4.length; _b++) {
+                            var member = members_4[_b];
                             if (isStatic === ts.hasStaticModifier(member) && hasLateBindableName(member)) {
                                 lateBindMember(symbol, earlySymbols, lateSymbols, member);
                             }
@@ -34813,7 +34816,7 @@ var ts;
             var numberIndexInfo;
             var types = type.types;
             var mixinCount = ts.countWhere(types, isMixinConstructorType);
-            var _loop_2 = function (i) {
+            var _loop_5 = function (i) {
                 var t = type.types[i];
                 // When an intersection type contains mixin constructor types, the construct signatures from
                 // those types are discarded and their return types are mixed into the return types of all
@@ -34836,7 +34839,7 @@ var ts;
                 numberIndexInfo = intersectIndexInfos(numberIndexInfo, getIndexInfoOfType(t, 1 /* Number */));
             };
             for (var i = 0; i < types.length; i++) {
-                _loop_2(i);
+                _loop_5(i);
             }
             setStructuredTypeMembers(type, emptySymbols, callSignatures, constructSignatures, stringIndexInfo, numberIndexInfo);
         }
@@ -36416,8 +36419,8 @@ var ts;
         function getTypeOfGlobalSymbol(symbol, arity) {
             function getTypeDeclaration(symbol) {
                 var declarations = symbol.declarations;
-                for (var _i = 0, declarations_2 = declarations; _i < declarations_2.length; _i++) {
-                    var declaration = declarations_2[_i];
+                for (var _i = 0, declarations_3 = declarations; _i < declarations_3.length; _i++) {
+                    var declaration = declarations_3[_i];
                     switch (declaration.kind) {
                         case 235 /* ClassDeclaration */:
                         case 236 /* InterfaceDeclaration */:
@@ -36878,7 +36881,7 @@ var ts;
             var unionType = types[unionIndex];
             var intersection = unionType.types;
             var i = types.length - 1;
-            var _loop_3 = function () {
+            var _loop_6 = function () {
                 var t = types[i];
                 if (t.flags & 67108864 /* UnionOfUnitTypes */) {
                     intersection = ts.filter(intersection, function (u) { return containsType(t.types, u); });
@@ -36887,7 +36890,7 @@ var ts;
                 i--;
             };
             while (i > unionIndex) {
-                _loop_3();
+                _loop_6();
             }
             if (intersection === unionType.types) {
                 return false;
@@ -38834,7 +38837,7 @@ var ts;
                         // check excess properties against discriminant type only, not the entire union
                         return hasExcessProperties(source, discriminant, /*discriminant*/ undefined, reportErrors);
                     }
-                    var _loop_4 = function (prop) {
+                    var _loop_7 = function (prop) {
                         if (!isKnownProperty(target, prop.escapedName, isComparingJsxAttributes)) {
                             if (reportErrors) {
                                 // We know *exactly* where things went wrong when comparing the types.
@@ -38873,7 +38876,7 @@ var ts;
                     };
                     for (var _i = 0, _a = getPropertiesOfObjectType(source); _i < _a.length; _i++) {
                         var prop = _a[_i];
-                        var state_3 = _loop_4(prop);
+                        var state_3 = _loop_7(prop);
                         if (typeof state_3 === "object")
                             return state_3.value;
                     }
@@ -39319,10 +39322,10 @@ var ts;
                 var modifiersRelated = relation === comparableRelation || (relation === identityRelation ? getMappedTypeModifiers(source) === getMappedTypeModifiers(target) :
                     getCombinedMappedTypeOptionality(source) <= getCombinedMappedTypeOptionality(target));
                 if (modifiersRelated) {
-                    var result_1;
-                    if (result_1 = isRelatedTo(getConstraintTypeFromMappedType(target), getConstraintTypeFromMappedType(source), reportErrors)) {
+                    var result_2;
+                    if (result_2 = isRelatedTo(getConstraintTypeFromMappedType(target), getConstraintTypeFromMappedType(source), reportErrors)) {
                         var mapper = createTypeMapper([getTypeParameterFromMappedType(source)], [getTypeParameterFromMappedType(target)]);
-                        return result_1 & isRelatedTo(instantiateType(getTemplateTypeFromMappedType(source), mapper), getTemplateTypeFromMappedType(target), reportErrors);
+                        return result_2 & isRelatedTo(instantiateType(getTemplateTypeFromMappedType(source), mapper), getTemplateTypeFromMappedType(target), reportErrors);
                     }
                 }
                 return 0 /* False */;
@@ -44649,7 +44652,7 @@ var ts;
                 // Assignability failure - check each prop individually, and if that fails, fall back on the bad error span
                 if (ts.length(openingLikeElement.attributes.properties)) {
                     var reportedError = false;
-                    var _loop_5 = function (prop) {
+                    var _loop_8 = function (prop) {
                         if (ts.isJsxSpreadAttribute(prop))
                             return "continue";
                         var name = ts.idText(prop.name);
@@ -44663,7 +44666,7 @@ var ts;
                     };
                     for (var _b = 0, _c = openingLikeElement.attributes.properties; _b < _c.length; _b++) {
                         var prop = _c[_b];
-                        _loop_5(prop);
+                        _loop_8(prop);
                     }
                     if (reportedError) {
                         return;
@@ -45596,13 +45599,13 @@ var ts;
         function getEffectiveCallArguments(node) {
             if (node.kind === 189 /* TaggedTemplateExpression */) {
                 var template = node.template;
-                var args_1 = [undefined]; // TODO: GH#18217
+                var args_4 = [undefined]; // TODO: GH#18217
                 if (template.kind === 202 /* TemplateExpression */) {
                     ts.forEach(template.templateSpans, function (span) {
-                        args_1.push(span.expression);
+                        args_4.push(span.expression);
                     });
                 }
-                return args_1;
+                return args_4;
             }
             else if (node.kind === 150 /* Decorator */) {
                 // For a decorator, we return undefined as we will determine
@@ -49014,8 +49017,8 @@ var ts;
             }
             var duplicateFunctionDeclaration = false;
             var multipleConstructorImplementation = false;
-            for (var _i = 0, declarations_3 = declarations; _i < declarations_3.length; _i++) {
-                var current = declarations_3[_i];
+            for (var _i = 0, declarations_4 = declarations; _i < declarations_4.length; _i++) {
+                var current = declarations_4[_i];
                 var node = current;
                 var inAmbientContext = node.flags & 4194304 /* Ambient */;
                 var inAmbientContextOrInterface = node.parent.kind === 236 /* InterfaceDeclaration */ || node.parent.kind === 166 /* TypeLiteral */ || inAmbientContext;
@@ -49184,10 +49187,10 @@ var ts;
                     case 243 /* ImportEqualsDeclaration */:
                     case 246 /* NamespaceImport */:
                     case 245 /* ImportClause */:
-                        var result_2 = 0 /* None */;
+                        var result_3 = 0 /* None */;
                         var target = resolveAlias(getSymbolOfNode(d));
-                        ts.forEach(target.declarations, function (d) { result_2 |= getDeclarationSpaces(d); });
-                        return result_2;
+                        ts.forEach(target.declarations, function (d) { result_3 |= getDeclarationSpaces(d); });
+                        return result_3;
                     case 232 /* VariableDeclaration */:
                     case 182 /* BindingElement */:
                     case 234 /* FunctionDeclaration */:
@@ -49984,8 +49987,8 @@ var ts;
                         : ts.createDiagnosticForNode(declarationList.parent.kind === 214 /* VariableStatement */ ? declarationList.parent : declarationList, ts.Diagnostics.All_variables_are_unused));
                 }
                 else {
-                    for (var _i = 0, declarations_4 = declarations; _i < declarations_4.length; _i++) {
-                        var decl = declarations_4[_i];
+                    for (var _i = 0, declarations_5 = declarations; _i < declarations_5.length; _i++) {
+                        var decl = declarations_5[_i];
                         addDiagnostic(0 /* Local */, ts.createDiagnosticForNode(decl, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, ts.idText(ts.cast(decl.name, ts.isIdentifier))));
                     }
                 }
@@ -51169,8 +51172,8 @@ var ts;
                 if (!areTypeParametersIdentical(declarations, type.localTypeParameters)) {
                     // Report an error on every conflicting declaration.
                     var name = symbolToString(symbol);
-                    for (var _i = 0, declarations_5 = declarations; _i < declarations_5.length; _i++) {
-                        var declaration = declarations_5[_i];
+                    for (var _i = 0, declarations_6 = declarations; _i < declarations_6.length; _i++) {
+                        var declaration = declarations_6[_i];
                         error(declaration.name, ts.Diagnostics.All_declarations_of_0_must_have_identical_type_parameters, name);
                     }
                 }
@@ -51179,8 +51182,8 @@ var ts;
         function areTypeParametersIdentical(declarations, targetParameters) {
             var maxTypeArgumentCount = ts.length(targetParameters);
             var minTypeArgumentCount = getMinTypeArgumentCount(targetParameters);
-            for (var _i = 0, declarations_6 = declarations; _i < declarations_6.length; _i++) {
-                var declaration = declarations_6[_i];
+            for (var _i = 0, declarations_7 = declarations; _i < declarations_7.length; _i++) {
+                var declaration = declarations_7[_i];
                 // If this declaration has too few or too many type parameters, we report an error
                 var sourceParameters = ts.getEffectiveTypeParameterDeclarations(declaration);
                 var numTypeParameters = sourceParameters.length;
@@ -51334,7 +51337,7 @@ var ts;
         function issueMemberSpecificError(node, typeWithThis, baseWithThis, broadDiag) {
             // iterate over all implemented properties and issue errors on each one which isn't compatible, rather than the class as a whole, if possible
             var issuedMemberError = false;
-            var _loop_6 = function (member) {
+            var _loop_9 = function (member) {
                 if (ts.hasStaticModifier(member)) {
                     return "continue";
                 }
@@ -51353,7 +51356,7 @@ var ts;
             };
             for (var _i = 0, _a = node.members; _i < _a.length; _i++) {
                 var member = _a[_i];
-                _loop_6(member);
+                _loop_9(member);
             }
             if (!issuedMemberError) {
                 // check again with diagnostics to generate a less-specific error
@@ -51638,12 +51641,12 @@ var ts;
             function evaluate(expr) {
                 switch (expr.kind) {
                     case 198 /* PrefixUnaryExpression */:
-                        var value_1 = evaluate(expr.operand);
-                        if (typeof value_1 === "number") {
+                        var value_2 = evaluate(expr.operand);
+                        if (typeof value_2 === "number") {
                             switch (expr.operator) {
-                                case 37 /* PlusToken */: return value_1;
-                                case 38 /* MinusToken */: return -value_1;
-                                case 52 /* TildeToken */: return ~value_1;
+                                case 37 /* PlusToken */: return value_2;
+                                case 38 /* MinusToken */: return -value_2;
+                                case 52 /* TildeToken */: return ~value_2;
                             }
                         }
                         break;
@@ -51782,8 +51785,8 @@ var ts;
         }
         function getFirstNonAmbientClassOrFunctionDeclaration(symbol) {
             var declarations = symbol.declarations;
-            for (var _i = 0, declarations_7 = declarations; _i < declarations_7.length; _i++) {
-                var declaration = declarations_7[_i];
+            for (var _i = 0, declarations_8 = declarations; _i < declarations_8.length; _i++) {
+                var declaration = declarations_8[_i];
                 if ((declaration.kind === 235 /* ClassDeclaration */ ||
                     (declaration.kind === 234 /* FunctionDeclaration */ && ts.nodeIsPresent(declaration.body))) &&
                     !(declaration.flags & 4194304 /* Ambient */)) {
@@ -52206,9 +52209,9 @@ var ts;
                     }
                 }
                 // Checks for export * conflicts
-                var exports = getExportsOfModule(moduleSymbol);
-                if (exports) {
-                    exports.forEach(function (_a, id) {
+                var exports_1 = getExportsOfModule(moduleSymbol);
+                if (exports_1) {
+                    exports_1.forEach(function (_a, id) {
                         var declarations = _a.declarations, flags = _a.flags;
                         if (id === "__export") {
                             return;
@@ -52225,8 +52228,8 @@ var ts;
                             return;
                         }
                         if (exportedDeclarationsCount > 1) {
-                            for (var _i = 0, declarations_8 = declarations; _i < declarations_8.length; _i++) {
-                                var declaration = declarations_8[_i];
+                            for (var _i = 0, declarations_9 = declarations; _i < declarations_9.length; _i++) {
+                                var declaration = declarations_9[_i];
                                 if (isNotOverload(declaration)) {
                                     diagnostics.add(ts.createDiagnosticForNode(declaration, ts.Diagnostics.Cannot_redeclare_exported_variable_0, ts.unescapeLeadingUnderscores(id)));
                                 }
@@ -54289,8 +54292,8 @@ var ts;
         }
         function checkGrammarForOmittedArgument(args) {
             if (args) {
-                for (var _i = 0, args_2 = args; _i < args_2.length; _i++) {
-                    var arg = args_2[_i];
+                for (var _i = 0, args_5 = args; _i < args_5.length; _i++) {
+                    var arg = args_5[_i];
                     if (arg.kind === 206 /* OmittedExpression */) {
                         return grammarErrorAtPos(arg, arg.pos, 0, ts.Diagnostics.Argument_expression_expected);
                     }
@@ -60261,8 +60264,8 @@ var ts;
         }
         var subtreeFlags = 0 /* None */;
         var nodeArrayFlags = 0 /* None */;
-        for (var _i = 0, nodes_2 = nodes; _i < nodes_2.length; _i++) {
-            var node = nodes_2[_i];
+        for (var _i = 0, nodes_3 = nodes; _i < nodes_3.length; _i++) {
+            var node = nodes_3[_i];
             subtreeFlags |= aggregateTransformFlagsForNode(node);
             nodeArrayFlags |= node.transformFlags & ~536870912 /* HasComputedFlags */;
         }
@@ -62327,8 +62330,8 @@ var ts;
         function generateClassElementDecorationExpressions(node, isStatic) {
             var members = getDecoratedClassElements(node, isStatic);
             var expressions;
-            for (var _i = 0, members_4 = members; _i < members_4.length; _i++) {
-                var member = members_4[_i];
+            for (var _i = 0, members_5 = members; _i < members_5.length; _i++) {
+                var member = members_5[_i];
                 var expression = generateClassElementDecorationExpression(node, member);
                 if (expression) {
                     if (!expressions) {
@@ -74870,8 +74873,8 @@ var ts;
                 return;
             }
             necessaryTypeRefernces = necessaryTypeRefernces || ts.createMap();
-            for (var _i = 0, typeReferenceDirectives_1 = typeReferenceDirectives; _i < typeReferenceDirectives_1.length; _i++) {
-                var ref = typeReferenceDirectives_1[_i];
+            for (var _i = 0, typeReferenceDirectives_2 = typeReferenceDirectives; _i < typeReferenceDirectives_2.length; _i++) {
+                var ref = typeReferenceDirectives_2[_i];
                 necessaryTypeRefernces.set(ref, true);
             }
         }
@@ -75779,7 +75782,7 @@ var ts;
             var prop = ts.createProperty(/*decorators*/ undefined, maskModifiers(node, /*mask*/ undefined, (!accessors.setAccessor) ? 64 /* Readonly */ : 0 /* None */), node.name, node.questionToken, ensureType(node, accessorType), /*initializer*/ undefined);
             var leadingsSyntheticCommentRanges = accessors.secondAccessor && ts.getLeadingCommentRangesOfNode(accessors.secondAccessor, currentSourceFile);
             if (leadingsSyntheticCommentRanges) {
-                var _loop_7 = function (range) {
+                var _loop_10 = function (range) {
                     if (range.kind === 3 /* MultiLineCommentTrivia */) {
                         var text = currentSourceFile.text.slice(range.pos + 2, range.end - 2);
                         var lines = text.split(/\r\n?|\n/g);
@@ -75793,7 +75796,7 @@ var ts;
                 };
                 for (var _i = 0, leadingsSyntheticCommentRanges_1 = leadingsSyntheticCommentRanges; _i < leadingsSyntheticCommentRanges_1.length; _i++) {
                     var range = leadingsSyntheticCommentRanges_1[_i];
-                    _loop_7(range);
+                    _loop_10(range);
                 }
             }
             return prop;
@@ -76002,8 +76005,8 @@ var ts;
             }
         };
         // Ensure the parse tree is clean before applying transformations
-        for (var _i = 0, nodes_3 = nodes; _i < nodes_3.length; _i++) {
-            var node = nodes_3[_i];
+        for (var _i = 0, nodes_4 = nodes; _i < nodes_4.length; _i++) {
+            var node = nodes_4[_i];
             ts.disposeEmitNodes(ts.getSourceFileOfNode(ts.getParseTreeNode(node)));
         }
         ts.performance.mark("beforeTransform");
@@ -76194,8 +76197,8 @@ var ts;
         function dispose() {
             if (state < 3 /* Disposed */) {
                 // Clean up emit nodes on parse tree
-                for (var _i = 0, nodes_4 = nodes; _i < nodes_4.length; _i++) {
-                    var node = nodes_4[_i];
+                for (var _i = 0, nodes_5 = nodes; _i < nodes_5.length; _i++) {
+                    var node = nodes_5[_i];
                     ts.disposeEmitNodes(ts.getSourceFileOfNode(ts.getParseTreeNode(node)));
                 }
                 // Release references to external entries for GC purposes.
@@ -79751,8 +79754,8 @@ var ts;
         function writeLines(text) {
             var lines = text.split(/\r\n?|\n/g);
             var indentation = ts.guessIndentation(lines);
-            for (var _a = 0, lines_1 = lines; _a < lines_1.length; _a++) {
-                var lineText = lines_1[_a];
+            for (var _a = 0, lines_2 = lines; _a < lines_2.length; _a++) {
+                var lineText = lines_2[_a];
                 var line = indentation ? lineText.slice(indentation) : lineText;
                 if (line.length) {
                     writeLine();
@@ -81280,13 +81283,13 @@ var ts;
                 // which per above occurred during the current program creation.
                 // Since we assume the filesystem does not change during program creation,
                 // it is safe to reuse resolutions from the earlier call.
-                var result_3 = [];
+                var result_4 = [];
                 for (var _i = 0, moduleNames_1 = moduleNames; _i < moduleNames_1.length; _i++) {
                     var moduleName = moduleNames_1[_i];
                     var resolvedModule = file.resolvedModules.get(moduleName);
-                    result_3.push(resolvedModule);
+                    result_4.push(resolvedModule);
                 }
-                return result_3;
+                return result_4;
             }
             // At this point, we know at least one of the following hold:
             // - file has local declarations for ambient modules
@@ -81984,8 +81987,8 @@ var ts;
                             }
                             break;
                     }
-                    for (var _b = 0, nodes_5 = nodes; _b < nodes_5.length; _b++) {
-                        var node = nodes_5[_b];
+                    for (var _b = 0, nodes_6 = nodes; _b < nodes_6.length; _b++) {
+                        var node = nodes_6[_b];
                         walk(node);
                     }
                 }
@@ -82642,14 +82645,14 @@ var ts;
             if (options.composite && rootNames.length < files.length) {
                 var normalizedRootNames = rootNames.map(function (r) { return ts.normalizePath(r).toLowerCase(); });
                 var sourceFiles = files.filter(function (f) { return !f.isDeclarationFile; }).map(function (f) { return ts.normalizePath(f.path).toLowerCase(); });
-                var _loop_8 = function (file) {
+                var _loop_11 = function (file) {
                     if (normalizedRootNames.every(function (r) { return r !== file; })) {
                         programDiagnostics.add(ts.createCompilerDiagnostic(ts.Diagnostics.File_0_is_not_in_project_file_list_Projects_must_list_all_files_or_use_an_include_pattern, file));
                     }
                 };
                 for (var _i = 0, sourceFiles_4 = sourceFiles; _i < sourceFiles_4.length; _i++) {
                     var file = sourceFiles_4[_i];
-                    _loop_8(file);
+                    _loop_11(file);
                 }
             }
             if (options.paths) {
@@ -84518,8 +84521,8 @@ var ts;
         function tryGetAnyFileFromPath(host, path) {
             // We check all js, `node` and `json` extensions in addition to TS, since node module resolution would also choose those over the directory
             var extensions = ts.getSupportedExtensions({ allowJs: true }, [{ extension: "node", isMixedContent: false }, { extension: "json", isMixedContent: false, scriptKind: 6 /* JSON */ }]);
-            for (var _i = 0, extensions_1 = extensions; _i < extensions_1.length; _i++) {
-                var e = extensions_1[_i];
+            for (var _i = 0, extensions_3 = extensions; _i < extensions_3.length; _i++) {
+                var e = extensions_3[_i];
                 var fullPath = path + e;
                 if (host.fileExists(fullPath)) { // TODO: GH#18217
                     return fullPath;
@@ -85417,7 +85420,6 @@ var ts;
             getKeys: getKeys
         };
     }
-    ts.createDependencyMapper = createDependencyMapper;
     function getOutputDeclarationFileName(inputFileName, configFile) {
         var relativePath = ts.getRelativePathFromDirectory(rootDirOfOptions(configFile.options, configFile.options.configFilePath), inputFileName, /*ignoreCase*/ true);
         var outputPath = ts.resolvePath(configFile.options.declarationDir || configFile.options.outDir || ts.getDirectoryPath(configFile.options.configFilePath), relativePath);
@@ -85543,8 +85545,8 @@ var ts;
         var clean = false;
         var watch = false;
         var projects = [];
-        for (var _i = 0, args_3 = args; _i < args_3.length; _i++) {
-            var arg = args_3[_i];
+        for (var _i = 0, args_6 = args; _i < args_6.length; _i++) {
+            var arg = args_6[_i];
             switch (arg.toLowerCase()) {
                 case "-v":
                 case "--verbose":
@@ -85568,23 +85570,28 @@ var ts;
                 case "--?":
                 case "-?":
                 case "--help":
-                    return ts.printHelp(buildOpts, "--build ");
+                    ts.printHelp(buildOpts, "--build ");
+                    return ts.ExitStatus.Success;
             }
             // Not a flag, parse as filename
             addProject(arg);
         }
         // Nonsensical combinations
         if (clean && force) {
-            return buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "force");
+            buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "force");
+            return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
         }
         if (clean && verbose) {
-            return buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "verbose");
+            buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "verbose");
+            return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
         }
         if (clean && watch) {
-            return buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "watch");
+            buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "watch");
+            return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
         }
         if (watch && dry) {
-            return buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "watch", "dry");
+            buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "watch", "dry");
+            return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
         }
         if (projects.length === 0) {
             // tsc -b invoked with no extra arguments; act as if invoked with "tsc -b ."
@@ -85592,14 +85599,13 @@ var ts;
         }
         var builder = createSolutionBuilder(compilerHost, buildHost, projects, { dry: dry, force: force, verbose: verbose }, system);
         if (clean) {
-            builder.cleanAllProjects();
-        }
-        else {
-            builder.buildAllProjects();
+            return builder.cleanAllProjects();
         }
         if (watch) {
-            return builder.startWatching();
+            builder.startWatching();
+            return undefined;
         }
+        return builder.buildAllProjects();
         function addProject(projectSpecification) {
             var fileName = ts.resolvePath(compilerHost.getCurrentDirectory(), projectSpecification);
             var refPath = ts.resolveProjectReferencePath(compilerHost, { path: fileName });
@@ -85647,7 +85653,7 @@ var ts;
                 // Everything is broken - we don't even know what to watch. Give up.
                 return;
             }
-            var _loop_9 = function (resolved) {
+            var _loop_12 = function (resolved) {
                 var cfg = configFileCache.parseConfigFile(resolved);
                 if (cfg) {
                     // Watch this file
@@ -85674,7 +85680,7 @@ var ts;
             };
             for (var _i = 0, _a = graph.buildQueue; _i < _a.length; _i++) {
                 var resolved = _a[_i];
-                _loop_9(resolved);
+                _loop_12(resolved);
             }
             function invalidateProjectAndScheduleBuilds(resolved) {
                 invalidateProject(resolved);
@@ -85855,9 +85861,11 @@ var ts;
                 }
             }
             var pseudoUpToDate = false;
+            var usesPrepend = false;
             if (project.projectReferences) {
                 for (var _c = 0, _d = project.projectReferences; _c < _d.length; _c++) {
                     var ref = _d[_c];
+                    usesPrepend = usesPrepend || !!(ref.prepend);
                     var resolvedRef = ts.resolveProjectReferencePath(compilerHost, ref);
                     var refStatus = getUpToDateStatus(configFileCache.parseConfigFile(resolvedRef));
                     // An upstream project is blocked
@@ -85907,6 +85915,9 @@ var ts;
                     newerInputFileName: newestInputFileName
                 };
             }
+            if (usesPrepend) {
+                pseudoUpToDate = false;
+            }
             // Up to date
             return {
                 type: pseudoUpToDate ? UpToDateStatusType.UpToDateWithUpstreamTypes : UpToDateStatusType.UpToDate,
@@ -86110,14 +86121,17 @@ var ts;
         function cleanAllProjects() {
             var resolvedNames = getAllProjectsInScope();
             if (resolvedNames === undefined) {
-                return buildHost.message(ts.Diagnostics.Skipping_clean_because_not_all_projects_could_be_located);
+                buildHost.message(ts.Diagnostics.Skipping_clean_because_not_all_projects_could_be_located);
+                return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
             }
             var filesToDelete = getFilesToClean(resolvedNames);
             if (filesToDelete === undefined) {
-                return buildHost.message(ts.Diagnostics.Skipping_clean_because_not_all_projects_could_be_located);
+                buildHost.message(ts.Diagnostics.Skipping_clean_because_not_all_projects_could_be_located);
+                return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
             }
             if (context.options.dry) {
-                return buildHost.message(ts.Diagnostics.A_non_dry_build_would_delete_the_following_files_Colon_0, filesToDelete.map(function (f) { return "\r\n * " + f; }).join(""));
+                buildHost.message(ts.Diagnostics.A_non_dry_build_would_delete_the_following_files_Colon_0, filesToDelete.map(function (f) { return "\r\n * " + f; }).join(""));
+                return ts.ExitStatus.Success;
             }
             // Do this check later to allow --clean --dry to function even if the host can't delete files
             if (!compilerHost.deleteFile) {
@@ -86127,6 +86141,7 @@ var ts;
                 var output = filesToDelete_1[_i];
                 compilerHost.deleteFile(output);
             }
+            return ts.ExitStatus.Success;
         }
         function resolveProjectName(name) {
             var fullPath = ts.resolvePath(compilerHost.getCurrentDirectory(), name);
@@ -86155,13 +86170,15 @@ var ts;
         function buildAllProjects() {
             var graph = getGlobalDependencyGraph();
             if (graph === undefined)
-                return;
+                return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
             var queue = graph.buildQueue;
             reportBuildQueue(graph);
+            var anyFailed = false;
             for (var _i = 0, queue_1 = queue; _i < queue_1.length; _i++) {
                 var next = queue_1[_i];
                 var proj = configFileCache.parseConfigFile(next);
                 if (proj === undefined) {
+                    anyFailed = true;
                     break;
                 }
                 var status = getUpToDateStatus(proj);
@@ -86189,8 +86206,10 @@ var ts;
                     // Do nothing
                     continue;
                 }
-                buildSingleProject(next);
+                var buildResult = buildSingleProject(next);
+                anyFailed = anyFailed || !!(buildResult & BuildResultFlags.AnyErrors);
             }
+            return anyFailed ? ts.ExitStatus.DiagnosticsPresent_OutputsSkipped : ts.ExitStatus.Success;
         }
         /**
          * Report the build ordering inferred from the current project graph if we're in verbose mode
@@ -111557,6 +111576,7 @@ var TypeScript;
 var toolsVersion = ts.versionMajorMinor;
 //# sourceMappingURL=services.js.map
 "use strict";
+/* @internal */
 var ts;
 (function (ts) {
     var server;
diff --git a/lib/tsserverlibrary.d.ts b/lib/tsserverlibrary.d.ts
index 2cfb99444e5..6de868d459a 100644
--- a/lib/tsserverlibrary.d.ts
+++ b/lib/tsserverlibrary.d.ts
@@ -13,6 +13,13 @@ See the Apache Version 2.0 License for specific language governing permissions
 and limitations under the License.
 ***************************************************************************** */
 
+
+
+declare namespace ts {
+    const versionMajorMinor = "3.0";
+    /** The version of the TypeScript compiler release */
+    const version: string;
+}
 declare namespace ts {
     /**
      * Type of objects whose values are all of the same type.
@@ -22,6 +29,9 @@ declare namespace ts {
     interface MapLike<T> {
         [index: string]: T;
     }
+    interface SortedArray<T> extends Array<T> {
+        " __sortedArrayBrand": any;
+    }
     /** ES6 Map interface, only read methods included. */
     interface ReadonlyMap<T> {
         get(key: string): T | undefined;
@@ -52,6 +62,528 @@ declare namespace ts {
     interface Push<T> {
         push(...values: T[]): void;
     }
+    type EqualityComparer<T> = (a: T, b: T) => boolean;
+    type Comparer<T> = (a: T, b: T) => Comparison;
+    enum Comparison {
+        LessThan = -1,
+        EqualTo = 0,
+        GreaterThan = 1
+    }
+}
+declare namespace ts {
+    /** Create a new map. If a template object is provided, the map will copy entries from it. */
+    function createMap<T>(): Map<T>;
+    function createMapFromEntries<T>(entries: [string, T][]): Map<T>;
+    function createMapFromTemplate<T>(template: MapLike<T>): Map<T>;
+    const MapCtr: new <T>() => Map<T>;
+    function length(array: ReadonlyArray<any> | undefined): number;
+    /**
+     * Iterates through 'array' by index and performs the callback on each element of array until the callback
+     * returns a truthy value, then returns that value.
+     * If no such value is found, the callback is applied to each element of array and undefined is returned.
+     */
+    function forEach<T, U>(array: ReadonlyArray<T> | undefined, callback: (element: T, index: number) => U | undefined): U | undefined;
+    /** Like `forEach`, but suitable for use with numbers and strings (which may be falsy). */
+    function firstDefined<T, U>(array: ReadonlyArray<T> | undefined, callback: (element: T, index: number) => U | undefined): U | undefined;
+    function firstDefinedIterator<T, U>(iter: Iterator<T>, callback: (element: T) => U | undefined): U | undefined;
+    function zipWith<T, U, V>(arrayA: ReadonlyArray<T>, arrayB: ReadonlyArray<U>, callback: (a: T, b: U, index: number) => V): V[];
+    function zipToIterator<T, U>(arrayA: ReadonlyArray<T>, arrayB: ReadonlyArray<U>): Iterator<[T, U]>;
+    function zipToMap<T>(keys: ReadonlyArray<string>, values: ReadonlyArray<T>): Map<T>;
+    /**
+     * Iterates through `array` by index and performs the callback on each element of array until the callback
+     * returns a falsey value, then returns false.
+     * If no such value is found, the callback is applied to each element of array and `true` is returned.
+     */
+    function every<T>(array: ReadonlyArray<T>, callback: (element: T, index: number) => boolean): boolean;
+    /** Works like Array.prototype.find, returning `undefined` if no element satisfying the predicate is found. */
+    function find<T, U extends T>(array: ReadonlyArray<T>, predicate: (element: T, index: number) => element is U): U | undefined;
+    function find<T>(array: ReadonlyArray<T>, predicate: (element: T, index: number) => boolean): T | undefined;
+    function findLast<T, U extends T>(array: ReadonlyArray<T>, predicate: (element: T, index: number) => element is U): U | undefined;
+    function findLast<T>(array: ReadonlyArray<T>, predicate: (element: T, index: number) => boolean): T | undefined;
+    /** Works like Array.prototype.findIndex, returning `-1` if no element satisfying the predicate is found. */
+    function findIndex<T>(array: ReadonlyArray<T>, predicate: (element: T, index: number) => boolean, startIndex?: number): number;
+    function findLastIndex<T>(array: ReadonlyArray<T>, predicate: (element: T, index: number) => boolean, startIndex?: number): number;
+    /**
+     * Returns the first truthy result of `callback`, or else fails.
+     * This is like `forEach`, but never returns undefined.
+     */
+    function findMap<T, U>(array: ReadonlyArray<T>, callback: (element: T, index: number) => U | undefined): U;
+    function contains<T>(array: ReadonlyArray<T> | undefined, value: T, equalityComparer?: EqualityComparer<T>): boolean;
+    function arraysEqual<T>(a: ReadonlyArray<T>, b: ReadonlyArray<T>, equalityComparer?: EqualityComparer<T>): boolean;
+    function indexOfAnyCharCode(text: string, charCodes: ReadonlyArray<number>, start?: number): number;
+    function countWhere<T>(array: ReadonlyArray<T>, predicate: (x: T, i: number) => boolean): number;
+    /**
+     * Filters an array by a predicate function. Returns the same array instance if the predicate is
+     * true for all elements, otherwise returns a new array instance containing the filtered subset.
+     */
+    function filter<T, U extends T>(array: T[], f: (x: T) => x is U): U[];
+    function filter<T>(array: T[], f: (x: T) => boolean): T[];
+    function filter<T, U extends T>(array: ReadonlyArray<T>, f: (x: T) => x is U): ReadonlyArray<U>;
+    function filter<T, U extends T>(array: ReadonlyArray<T>, f: (x: T) => boolean): ReadonlyArray<T>;
+    function filter<T, U extends T>(array: T[] | undefined, f: (x: T) => x is U): U[] | undefined;
+    function filter<T>(array: T[] | undefined, f: (x: T) => boolean): T[] | undefined;
+    function filter<T, U extends T>(array: ReadonlyArray<T> | undefined, f: (x: T) => x is U): ReadonlyArray<U> | undefined;
+    function filter<T, U extends T>(array: ReadonlyArray<T> | undefined, f: (x: T) => boolean): ReadonlyArray<T> | undefined;
+    function filterMutate<T>(array: T[], f: (x: T, i: number, array: T[]) => boolean): void;
+    function clear(array: {}[]): void;
+    function map<T, U>(array: ReadonlyArray<T>, f: (x: T, i: number) => U): U[];
+    function map<T, U>(array: ReadonlyArray<T> | undefined, f: (x: T, i: number) => U): U[] | undefined;
+    function mapIterator<T, U>(iter: Iterator<T>, mapFn: (x: T) => U): Iterator<U>;
+    function sameMap<T>(array: T[], f: (x: T, i: number) => T): T[];
+    function sameMap<T>(array: ReadonlyArray<T>, f: (x: T, i: number) => T): ReadonlyArray<T>;
+    function sameMap<T>(array: T[] | undefined, f: (x: T, i: number) => T): T[] | undefined;
+    function sameMap<T>(array: ReadonlyArray<T> | undefined, f: (x: T, i: number) => T): ReadonlyArray<T> | undefined;
+    /**
+     * Flattens an array containing a mix of array or non-array elements.
+     *
+     * @param array The array to flatten.
+     */
+    function flatten<T>(array: ReadonlyArray<T | ReadonlyArray<T> | undefined>): T[];
+    function flatten<T>(array: ReadonlyArray<T | ReadonlyArray<T> | undefined> | undefined): T[] | undefined;
+    /**
+     * Maps an array. If the mapped value is an array, it is spread into the result.
+     *
+     * @param array The array to map.
+     * @param mapfn The callback used to map the result into one or more values.
+     */
+    function flatMap<T, U>(array: ReadonlyArray<T>, mapfn: (x: T, i: number) => U | ReadonlyArray<U> | undefined): U[];
+    function flatMap<T, U>(array: ReadonlyArray<T> | undefined, mapfn: (x: T, i: number) => U | ReadonlyArray<U> | undefined): U[] | undefined;
+    function flatMapIterator<T, U>(iter: Iterator<T>, mapfn: (x: T) => U[] | Iterator<U> | undefined): Iterator<U>;
+    /**
+     * Maps an array. If the mapped value is an array, it is spread into the result.
+     * Avoids allocation if all elements map to themselves.
+     *
+     * @param array The array to map.
+     * @param mapfn The callback used to map the result into one or more values.
+     */
+    function sameFlatMap<T>(array: T[], mapfn: (x: T, i: number) => T | ReadonlyArray<T>): T[];
+    function sameFlatMap<T>(array: ReadonlyArray<T>, mapfn: (x: T, i: number) => T | ReadonlyArray<T>): ReadonlyArray<T>;
+    function mapAllOrFail<T, U>(array: ReadonlyArray<T>, mapFn: (x: T, i: number) => U | undefined): U[] | undefined;
+    function mapDefined<T, U>(array: ReadonlyArray<T> | undefined, mapFn: (x: T, i: number) => U | undefined): U[];
+    function mapDefinedIterator<T, U>(iter: Iterator<T>, mapFn: (x: T) => U | undefined): Iterator<U>;
+    const emptyIterator: Iterator<never>;
+    function singleIterator<T>(value: T): Iterator<T>;
+    /**
+     * Maps contiguous spans of values with the same key.
+     *
+     * @param array The array to map.
+     * @param keyfn A callback used to select the key for an element.
+     * @param mapfn A callback used to map a contiguous chunk of values to a single value.
+     */
+    function spanMap<T, K, U>(array: ReadonlyArray<T>, keyfn: (x: T, i: number) => K, mapfn: (chunk: T[], key: K, start: number, end: number) => U): U[];
+    function spanMap<T, K, U>(array: ReadonlyArray<T> | undefined, keyfn: (x: T, i: number) => K, mapfn: (chunk: T[], key: K, start: number, end: number) => U): U[] | undefined;
+    function mapEntries<T, U>(map: ReadonlyMap<T>, f: (key: string, value: T) => [string, U]): Map<U>;
+    function mapEntries<T, U>(map: ReadonlyMap<T> | undefined, f: (key: string, value: T) => [string, U]): Map<U> | undefined;
+    function some<T>(array: ReadonlyArray<T> | undefined): array is ReadonlyArray<T>;
+    function some<T>(array: ReadonlyArray<T> | undefined, predicate: (value: T) => boolean): boolean;
+    /** Calls the callback with (start, afterEnd) index pairs for each range where 'pred' is true. */
+    function getRangesWhere<T>(arr: ReadonlyArray<T>, pred: (t: T) => boolean, cb: (start: number, afterEnd: number) => void): void;
+    function concatenate<T>(array1: T[], array2: T[]): T[];
+    function concatenate<T>(array1: ReadonlyArray<T>, array2: ReadonlyArray<T>): ReadonlyArray<T>;
+    function concatenate<T>(array1: T[] | undefined, array2: T[] | undefined): T[];
+    function concatenate<T>(array1: ReadonlyArray<T> | undefined, array2: ReadonlyArray<T> | undefined): ReadonlyArray<T>;
+    /**
+     * Deduplicates an unsorted array.
+     * @param equalityComparer An optional `EqualityComparer` used to determine if two values are duplicates.
+     * @param comparer An optional `Comparer` used to sort entries before comparison, though the
+     * result will remain in the original order in `array`.
+     */
+    function deduplicate<T>(array: ReadonlyArray<T>, equalityComparer?: EqualityComparer<T>, comparer?: Comparer<T>): T[];
+    function deduplicate<T>(array: ReadonlyArray<T> | undefined, equalityComparer?: EqualityComparer<T>, comparer?: Comparer<T>): T[] | undefined;
+    function insertSorted<T>(array: SortedArray<T>, insert: T, compare: Comparer<T>): void;
+    function sortAndDeduplicate<T>(array: ReadonlyArray<T>, comparer: Comparer<T>, equalityComparer?: EqualityComparer<T>): T[];
+    function arrayIsEqualTo<T>(array1: ReadonlyArray<T> | undefined, array2: ReadonlyArray<T> | undefined, equalityComparer?: (a: T, b: T) => boolean): boolean;
+    /**
+     * Compacts an array, removing any falsey elements.
+     */
+    function compact<T>(array: T[]): T[];
+    function compact<T>(array: ReadonlyArray<T>): ReadonlyArray<T>;
+    /**
+     * Gets the relative complement of `arrayA` with respect to `arrayB`, returning the elements that
+     * are not present in `arrayA` but are present in `arrayB`. Assumes both arrays are sorted
+     * based on the provided comparer.
+     */
+    function relativeComplement<T>(arrayA: T[] | undefined, arrayB: T[] | undefined, comparer: Comparer<T>): T[] | undefined;
+    function sum<T extends Record<K, number>, K extends string>(array: ReadonlyArray<T>, prop: K): number;
+    /**
+     * Appends a value to an array, returning the array.
+     *
+     * @param to The array to which `value` is to be appended. If `to` is `undefined`, a new array
+     * is created if `value` was appended.
+     * @param value The value to append to the array. If `value` is `undefined`, nothing is
+     * appended.
+     */
+    function append<T>(to: T[], value: T | undefined): T[];
+    function append<T>(to: T[] | undefined, value: T): T[];
+    function append<T>(to: T[] | undefined, value: T | undefined): T[] | undefined;
+    function append<T>(to: Push<T>, value: T | undefined): void;
+    /**
+     * Appends a range of value to an array, returning the array.
+     *
+     * @param to The array to which `value` is to be appended. If `to` is `undefined`, a new array
+     * is created if `value` was appended.
+     * @param from The values to append to the array. If `from` is `undefined`, nothing is
+     * appended. If an element of `from` is `undefined`, that element is not appended.
+     * @param start The offset in `from` at which to start copying values.
+     * @param end The offset in `from` at which to stop copying values (non-inclusive).
+     */
+    function addRange<T>(to: T[], from: ReadonlyArray<T> | undefined, start?: number, end?: number): T[];
+    function addRange<T>(to: T[] | undefined, from: ReadonlyArray<T> | undefined, start?: number, end?: number): T[] | undefined;
+    /**
+     * @return Whether the value was added.
+     */
+    function pushIfUnique<T>(array: T[], toAdd: T, equalityComparer?: EqualityComparer<T>): boolean;
+    /**
+     * Unlike `pushIfUnique`, this can take `undefined` as an input, and returns a new array.
+     */
+    function appendIfUnique<T>(array: T[] | undefined, toAdd: T, equalityComparer?: EqualityComparer<T>): T[];
+    /**
+     * Returns a new sorted array.
+     */
+    function sort<T>(array: ReadonlyArray<T>, comparer: Comparer<T>): T[];
+    function best<T>(iter: Iterator<T>, isBetter: (a: T, b: T) => boolean): T | undefined;
+    function arrayIterator<T>(array: ReadonlyArray<T>): Iterator<T>;
+    /**
+     * Stable sort of an array. Elements equal to each other maintain their relative position in the array.
+     */
+    function stableSort<T>(array: ReadonlyArray<T>, comparer: Comparer<T>): T[];
+    function rangeEquals<T>(array1: ReadonlyArray<T>, array2: ReadonlyArray<T>, pos: number, end: number): boolean;
+    /**
+     * Returns the element at a specific offset in an array if non-empty, `undefined` otherwise.
+     * A negative offset indicates the element should be retrieved from the end of the array.
+     */
+    function elementAt<T>(array: ReadonlyArray<T> | undefined, offset: number): T | undefined;
+    /**
+     * Returns the first element of an array if non-empty, `undefined` otherwise.
+     */
+    function firstOrUndefined<T>(array: ReadonlyArray<T>): T | undefined;
+    function first<T>(array: ReadonlyArray<T>): T;
+    /**
+     * Returns the last element of an array if non-empty, `undefined` otherwise.
+     */
+    function lastOrUndefined<T>(array: ReadonlyArray<T>): T | undefined;
+    function last<T>(array: ReadonlyArray<T>): T;
+    /**
+     * Returns the only element of an array if it contains only one element, `undefined` otherwise.
+     */
+    function singleOrUndefined<T>(array: ReadonlyArray<T> | undefined): T | undefined;
+    /**
+     * Returns the only element of an array if it contains only one element; otheriwse, returns the
+     * array.
+     */
+    function singleOrMany<T>(array: T[]): T | T[];
+    function singleOrMany<T>(array: ReadonlyArray<T>): T | ReadonlyArray<T>;
+    function singleOrMany<T>(array: T[] | undefined): T | T[] | undefined;
+    function singleOrMany<T>(array: ReadonlyArray<T> | undefined): T | ReadonlyArray<T> | undefined;
+    function replaceElement<T>(array: ReadonlyArray<T>, index: number, value: T): T[];
+    /**
+     * Performs a binary search, finding the index at which `value` occurs in `array`.
+     * If no such index is found, returns the 2's-complement of first index at which
+     * `array[index]` exceeds `value`.
+     * @param array A sorted array whose first element must be no larger than number
+     * @param value The value to be searched for in the array.
+     * @param keySelector A callback used to select the search key from `value` and each element of
+     * `array`.
+     * @param keyComparer A callback used to compare two keys in a sorted array.
+     * @param offset An offset into `array` at which to start the search.
+     */
+    function binarySearch<T, U>(array: ReadonlyArray<T>, value: T, keySelector: (v: T) => U, keyComparer: Comparer<U>, offset?: number): number;
+    function reduceLeft<T, U>(array: ReadonlyArray<T> | undefined, f: (memo: U, value: T, i: number) => U, initial: U, start?: number, count?: number): U;
+    function reduceLeft<T>(array: ReadonlyArray<T>, f: (memo: T, value: T, i: number) => T): T | undefined;
+    /**
+     * Indicates whether a map-like contains an own property with the specified key.
+     *
+     * @param map A map-like.
+     * @param key A property key.
+     */
+    function hasProperty(map: MapLike<any>, key: string): boolean;
+    /**
+     * Gets the value of an owned property in a map-like.
+     *
+     * @param map A map-like.
+     * @param key A property key.
+     */
+    function getProperty<T>(map: MapLike<T>, key: string): T | undefined;
+    /**
+     * Gets the owned, enumerable property keys of a map-like.
+     */
+    function getOwnKeys<T>(map: MapLike<T>): string[];
+    function getOwnValues<T>(sparseArray: T[]): T[];
+    /** Shims `Array.from`. */
+    function arrayFrom<T, U>(iterator: Iterator<T>, map: (t: T) => U): U[];
+    function arrayFrom<T>(iterator: Iterator<T>): T[];
+    function assign<T extends object>(t: T, ...args: (T | undefined)[]): T;
+    /**
+     * Performs a shallow equality comparison of the contents of two map-likes.
+     *
+     * @param left A map-like whose properties should be compared.
+     * @param right A map-like whose properties should be compared.
+     */
+    function equalOwnProperties<T>(left: MapLike<T> | undefined, right: MapLike<T> | undefined, equalityComparer?: EqualityComparer<T>): boolean;
+    /**
+     * Creates a map from the elements of an array.
+     *
+     * @param array the array of input elements.
+     * @param makeKey a function that produces a key for a given element.
+     *
+     * This function makes no effort to avoid collisions; if any two elements produce
+     * the same key with the given 'makeKey' function, then the element with the higher
+     * index in the array will be the one associated with the produced key.
+     */
+    function arrayToMap<T>(array: ReadonlyArray<T>, makeKey: (value: T) => string | undefined): Map<T>;
+    function arrayToMap<T, U>(array: ReadonlyArray<T>, makeKey: (value: T) => string | undefined, makeValue: (value: T) => U): Map<U>;
+    function arrayToNumericMap<T>(array: ReadonlyArray<T>, makeKey: (value: T) => number): T[];
+    function arrayToNumericMap<T, U>(array: ReadonlyArray<T>, makeKey: (value: T) => number, makeValue: (value: T) => U): U[];
+    function arrayToMultiMap<T>(values: ReadonlyArray<T>, makeKey: (value: T) => string): MultiMap<T>;
+    function arrayToMultiMap<T, U>(values: ReadonlyArray<T>, makeKey: (value: T) => string, makeValue: (value: T) => U): MultiMap<U>;
+    function group<T>(values: ReadonlyArray<T>, getGroupId: (value: T) => string): ReadonlyArray<ReadonlyArray<T>>;
+    function clone<T>(object: T): T;
+    function extend<T1, T2>(first: T1, second: T2): T1 & T2;
+    interface MultiMap<T> extends Map<T[]> {
+        /**
+         * Adds the value to an array of values associated with the key, and returns the array.
+         * Creates the array if it does not already exist.
+         */
+        add(key: string, value: T): T[];
+        /**
+         * Removes a value from an array of values associated with the key.
+         * Does not preserve the order of those values.
+         * Does nothing if `key` is not in `map`, or `value` is not in `map[key]`.
+         */
+        remove(key: string, value: T): void;
+    }
+    function createMultiMap<T>(): MultiMap<T>;
+    /**
+     * Tests whether a value is an array.
+     */
+    function isArray(value: any): value is ReadonlyArray<{}>;
+    function toArray<T>(value: T | T[]): T[];
+    function toArray<T>(value: T | ReadonlyArray<T>): ReadonlyArray<T>;
+    /**
+     * Tests whether a value is string
+     */
+    function isString(text: any): text is string;
+    function tryCast<TOut extends TIn, TIn = any>(value: TIn | undefined, test: (value: TIn) => value is TOut): TOut | undefined;
+    function cast<TOut extends TIn, TIn = any>(value: TIn | undefined, test: (value: TIn) => value is TOut): TOut;
+    /** Does nothing. */
+    function noop(_?: {} | null | undefined): void;
+    /** Do nothing and return false */
+    function returnFalse(): false;
+    /** Do nothing and return true */
+    function returnTrue(): true;
+    /** Returns its argument. */
+    function identity<T>(x: T): T;
+    /** Returns lower case string */
+    function toLowerCase(x: string): string;
+    /** Throws an error because a function is not implemented. */
+    function notImplemented(): never;
+    function memoize<T>(callback: () => T): () => T;
+    /**
+     * High-order function, creates a function that executes a function composition.
+     * For example, `chain(a, b)` is the equivalent of `x => ((a', b') => y => b'(a'(y)))(a(x), b(x))`
+     *
+     * @param args The functions to chain.
+     */
+    function chain<T, U>(...args: ((t: T) => (u: U) => U)[]): (t: T) => (u: U) => U;
+    /**
+     * High-order function, composes functions. Note that functions are composed inside-out;
+     * for example, `compose(a, b)` is the equivalent of `x => b(a(x))`.
+     *
+     * @param args The functions to compose.
+     */
+    function compose<T>(...args: ((t: T) => T)[]): (t: T) => T;
+    enum AssertionLevel {
+        None = 0,
+        Normal = 1,
+        Aggressive = 2,
+        VeryAggressive = 3
+    }
+    /**
+     * Safer version of `Function` which should not be called.
+     * Every function should be assignable to this, but this should not be assignable to every function.
+     */
+    type AnyFunction = (...args: never[]) => void;
+    namespace Debug {
+        let currentAssertionLevel: AssertionLevel;
+        let isDebugging: boolean;
+        function shouldAssert(level: AssertionLevel): boolean;
+        function assert(expression: boolean, message?: string, verboseDebugInfo?: string | (() => string), stackCrawlMark?: AnyFunction): void;
+        function assertEqual<T>(a: T, b: T, msg?: string, msg2?: string): void;
+        function assertLessThan(a: number, b: number, msg?: string): void;
+        function assertLessThanOrEqual(a: number, b: number): void;
+        function assertGreaterThanOrEqual(a: number, b: number): void;
+        function fail(message?: string, stackCrawlMark?: AnyFunction): never;
+        function assertDefined<T>(value: T | null | undefined, message?: string): T;
+        function assertEachDefined<T, A extends ReadonlyArray<T>>(value: A, message?: string): A;
+        function assertNever(member: never, message?: string, stackCrawlMark?: AnyFunction): never;
+        function getFunctionName(func: AnyFunction): any;
+    }
+    function equateValues<T>(a: T, b: T): boolean;
+    /**
+     * Compare the equality of two strings using a case-sensitive ordinal comparison.
+     *
+     * Case-sensitive comparisons compare both strings one code-point at a time using the integer
+     * value of each code-point after applying `toUpperCase` to each string. We always map both
+     * strings to their upper-case form as some unicode characters do not properly round-trip to
+     * lowercase (such as `ẞ` (German sharp capital s)).
+     */
+    function equateStringsCaseInsensitive(a: string, b: string): boolean;
+    /**
+     * Compare the equality of two strings using a case-sensitive ordinal comparison.
+     *
+     * Case-sensitive comparisons compare both strings one code-point at a time using the
+     * integer value of each code-point.
+     */
+    function equateStringsCaseSensitive(a: string, b: string): boolean;
+    /**
+     * Compare two numeric values for their order relative to each other.
+     * To compare strings, use any of the `compareStrings` functions.
+     */
+    function compareValues(a: number | undefined, b: number | undefined): Comparison;
+    function min<T>(a: T, b: T, compare: Comparer<T>): T;
+    /**
+     * Compare two strings using a case-insensitive ordinal comparison.
+     *
+     * Ordinal comparisons are based on the difference between the unicode code points of both
+     * strings. Characters with multiple unicode representations are considered unequal. Ordinal
+     * comparisons provide predictable ordering, but place "a" after "B".
+     *
+     * Case-insensitive comparisons compare both strings one code-point at a time using the integer
+     * value of each code-point after applying `toUpperCase` to each string. We always map both
+     * strings to their upper-case form as some unicode characters do not properly round-trip to
+     * lowercase (such as `ẞ` (German sharp capital s)).
+     */
+    function compareStringsCaseInsensitive(a: string, b: string): Comparison;
+    /**
+     * Compare two strings using a case-sensitive ordinal comparison.
+     *
+     * Ordinal comparisons are based on the difference between the unicode code points of both
+     * strings. Characters with multiple unicode representations are considered unequal. Ordinal
+     * comparisons provide predictable ordering, but place "a" after "B".
+     *
+     * Case-sensitive comparisons compare both strings one code-point at a time using the integer
+     * value of each code-point.
+     */
+    function compareStringsCaseSensitive(a: string | undefined, b: string | undefined): Comparison;
+    function getStringComparer(ignoreCase?: boolean): typeof compareStringsCaseInsensitive;
+    function getUILocale(): string | undefined;
+    function setUILocale(value: string | undefined): void;
+    /**
+     * Compare two strings in a using the case-sensitive sort behavior of the UI locale.
+     *
+     * Ordering is not predictable between different host locales, but is best for displaying
+     * ordered data for UI presentation. Characters with multiple unicode representations may
+     * be considered equal.
+     *
+     * Case-sensitive comparisons compare strings that differ in base characters, or
+     * accents/diacritic marks, or case as unequal.
+     */
+    function compareStringsCaseSensitiveUI(a: string, b: string): Comparison;
+    function compareProperties<T, K extends keyof T>(a: T | undefined, b: T | undefined, key: K, comparer: Comparer<T[K]>): Comparison;
+    /** True is greater than false. */
+    function compareBooleans(a: boolean, b: boolean): Comparison;
+    /**
+     * Given a name and a list of names that are *not* equal to the name, return a spelling suggestion if there is one that is close enough.
+     * Names less than length 3 only check for case-insensitive equality, not Levenshtein distance.
+     *
+     * If there is a candidate that's the same except for case, return that.
+     * If there is a candidate that's within one edit of the name, return that.
+     * Otherwise, return the candidate with the smallest Levenshtein distance,
+     *    except for candidates:
+     *      * With no name
+     *      * Whose length differs from the target name by more than 0.34 of the length of the name.
+     *      * Whose levenshtein distance is more than 0.4 of the length of the name
+     *        (0.4 allows 1 substitution/transposition for every 5 characters,
+     *         and 1 insertion/deletion at 3 characters)
+     */
+    function getSpellingSuggestion<T>(name: string, candidates: T[], getName: (candidate: T) => string | undefined): T | undefined;
+    function endsWith(str: string, suffix: string): boolean;
+    function removeSuffix(str: string, suffix: string): string;
+    function tryRemoveSuffix(str: string, suffix: string): string | undefined;
+    function stringContains(str: string, substring: string): boolean;
+    function fileExtensionIs(path: string, extension: string): boolean;
+    function fileExtensionIsOneOf(path: string, extensions: ReadonlyArray<string>): boolean;
+    /**
+     * Takes a string like "jquery-min.4.2.3" and returns "jquery"
+     */
+    function removeMinAndVersionNumbers(fileName: string): string;
+    /** Remove an item from an array, moving everything to its right one space left. */
+    function orderedRemoveItem<T>(array: T[], item: T): boolean;
+    /** Remove an item by index from an array, moving everything to its right one space left. */
+    function orderedRemoveItemAt<T>(array: T[], index: number): void;
+    function unorderedRemoveItemAt<T>(array: T[], index: number): void;
+    /** Remove the *first* occurrence of `item` from the array. */
+    function unorderedRemoveItem<T>(array: T[], item: T): boolean;
+    type GetCanonicalFileName = (fileName: string) => string;
+    function createGetCanonicalFileName(useCaseSensitiveFileNames: boolean): GetCanonicalFileName;
+    /** Represents a "prefix*suffix" pattern. */
+    interface Pattern {
+        prefix: string;
+        suffix: string;
+    }
+    function patternText({ prefix, suffix }: Pattern): string;
+    /**
+     * Given that candidate matches pattern, returns the text matching the '*'.
+     * E.g.: matchedText(tryParsePattern("foo*baz"), "foobarbaz") === "bar"
+     */
+    function matchedText(pattern: Pattern, candidate: string): string;
+    /** Return the object corresponding to the best pattern to match `candidate`. */
+    function findBestPatternMatch<T>(values: ReadonlyArray<T>, getPattern: (value: T) => Pattern, candidate: string): T | undefined;
+    function startsWith(str: string, prefix: string): boolean;
+    function removePrefix(str: string, prefix: string): string;
+    function tryRemovePrefix(str: string, prefix: string): string | undefined;
+    function and<T>(f: (arg: T) => boolean, g: (arg: T) => boolean): (arg: T) => boolean;
+    function or<T>(f: (arg: T) => boolean, g: (arg: T) => boolean): (arg: T) => boolean;
+    function assertTypeIsNever(_: never): void;
+    function singleElementArray<T>(t: T | undefined): T[] | undefined;
+    function enumerateInsertsAndDeletes<T, U>(newItems: ReadonlyArray<T>, oldItems: ReadonlyArray<U>, comparer: (a: T, b: U) => Comparison, inserted: (newItem: T) => void, deleted: (oldItem: U) => void, unchanged?: (oldItem: U, newItem: T) => void): void;
+}
+declare namespace ts {
+    /** Gets a timestamp with (at least) ms resolution */
+    const timestamp: () => number;
+}
+/** Performance measurements for the compiler. */
+declare namespace ts.performance {
+    /**
+     * Marks a performance event.
+     *
+     * @param markName The name of the mark.
+     */
+    function mark(markName: string): void;
+    /**
+     * Adds a performance measurement with the specified name.
+     *
+     * @param measureName The name of the performance measurement.
+     * @param startMarkName The name of the starting mark. If not supplied, the point at which the
+     *      profiler was enabled is used.
+     * @param endMarkName The name of the ending mark. If not supplied, the current timestamp is
+     *      used.
+     */
+    function measure(measureName: string, startMarkName?: string, endMarkName?: string): void;
+    /**
+     * Gets the number of times a marker was encountered.
+     *
+     * @param markName The name of the mark.
+     */
+    function getCount(markName: string): number;
+    /**
+     * Gets the total duration of all measurements with the supplied name.
+     *
+     * @param measureName The name of the measure whose durations should be accumulated.
+     */
+    function getDuration(measureName: string): number;
+    /**
+     * Iterate over each measure, performing some action
+     *
+     * @param cb The action to perform for each measure
+     */
+    function forEachMeasure(cb: (measureName: string, duration: number) => void): void;
+    /** Enables (and resets) performance measurements for the compiler. */
+    function enable(): void;
+    /** Disables performance measurements for the compiler. */
+    function disable(): void;
+}
+declare namespace ts {
     type Path = string & {
         __pathBrand: any;
     };
@@ -396,7 +928,9 @@ declare namespace ts {
         FirstJSDocNode = 278,
         LastJSDocNode = 298,
         FirstJSDocTagNode = 289,
-        LastJSDocTagNode = 298
+        LastJSDocTagNode = 298,
+        FirstContextualKeyword = 117,
+        LastContextualKeyword = 145
     }
     enum NodeFlags {
         None = 0,
@@ -419,13 +953,18 @@ declare namespace ts {
         JavaScriptFile = 65536,
         ThisNodeOrAnySubNodesHasError = 131072,
         HasAggregatedChildData = 262144,
+        PossiblyContainsDynamicImport = 524288,
+        PossiblyContainsImportMeta = 1048576,
         JSDoc = 2097152,
+        Ambient = 4194304,
+        InWithStatement = 8388608,
         JsonFile = 16777216,
         BlockScoped = 3,
         ReachabilityCheckFlags = 384,
         ReachabilityAndEmitFlags = 1408,
         ContextFlags = 12679168,
-        TypeExcludesFlags = 20480
+        TypeExcludesFlags = 20480,
+        PermanentlySetIncrementalFlags = 1572864
     }
     enum ModifierFlags {
         None = 0,
@@ -456,21 +995,42 @@ declare namespace ts {
         IntrinsicIndexedElement = 2,
         IntrinsicElement = 3
     }
+    enum RelationComparisonResult {
+        Succeeded = 1,
+        Failed = 2,
+        FailedAndReported = 3
+    }
     interface Node extends TextRange {
         kind: SyntaxKind;
         flags: NodeFlags;
+        modifierFlagsCache?: ModifierFlags;
+        transformFlags: TransformFlags;
         decorators?: NodeArray<Decorator>;
         modifiers?: ModifiersArray;
+        id?: number;
         parent: Node;
+        original?: Node;
+        symbol: Symbol;
+        locals?: SymbolTable;
+        nextContainer?: Node;
+        localSymbol?: Symbol;
+        flowNode?: FlowNode;
+        emitNode?: EmitNode;
+        contextualType?: Type;
+        contextualMapper?: TypeMapper;
     }
     interface JSDocContainer {
+        jsDoc?: JSDoc[];
+        jsDocCache?: ReadonlyArray<JSDocTag>;
     }
     type HasJSDoc = ParameterDeclaration | CallSignatureDeclaration | ConstructSignatureDeclaration | MethodSignature | PropertySignature | ArrowFunction | ParenthesizedExpression | SpreadAssignment | ShorthandPropertyAssignment | PropertyAssignment | FunctionExpression | LabeledStatement | ExpressionStatement | VariableStatement | FunctionDeclaration | ConstructorDeclaration | MethodDeclaration | PropertyDeclaration | AccessorDeclaration | ClassLikeDeclaration | InterfaceDeclaration | TypeAliasDeclaration | EnumMember | EnumDeclaration | ModuleDeclaration | ImportEqualsDeclaration | IndexSignatureDeclaration | FunctionTypeNode | ConstructorTypeNode | JSDocFunctionType | EndOfFileToken;
     type HasType = SignatureDeclaration | VariableDeclaration | ParameterDeclaration | PropertySignature | PropertyDeclaration | TypePredicateNode | ParenthesizedTypeNode | TypeOperatorNode | MappedTypeNode | AssertionExpression | TypeAliasDeclaration | JSDocTypeExpression | JSDocNonNullableType | JSDocNullableType | JSDocOptionalType | JSDocVariadicType;
     type HasInitializer = HasExpressionInitializer | ForStatement | ForInStatement | ForOfStatement | JsxAttribute;
     type HasExpressionInitializer = VariableDeclaration | ParameterDeclaration | BindingElement | PropertySignature | PropertyDeclaration | PropertyAssignment | EnumMember;
+    type MutableNodeArray<T extends Node> = NodeArray<T> & T[];
     interface NodeArray<T extends Node> extends ReadonlyArray<T>, TextRange {
         hasTrailingComma?: boolean;
+        transformFlags: TransformFlags;
     }
     interface Token<TKind extends SyntaxKind> extends Node {
         kind: TKind;
@@ -490,6 +1050,17 @@ declare namespace ts {
     type MinusToken = Token<SyntaxKind.MinusToken>;
     type Modifier = Token<SyntaxKind.AbstractKeyword> | Token<SyntaxKind.AsyncKeyword> | Token<SyntaxKind.ConstKeyword> | Token<SyntaxKind.DeclareKeyword> | Token<SyntaxKind.DefaultKeyword> | Token<SyntaxKind.ExportKeyword> | Token<SyntaxKind.PublicKeyword> | Token<SyntaxKind.PrivateKeyword> | Token<SyntaxKind.ProtectedKeyword> | Token<SyntaxKind.ReadonlyKeyword> | Token<SyntaxKind.StaticKeyword>;
     type ModifiersArray = NodeArray<Modifier>;
+    enum GeneratedIdentifierFlags {
+        None = 0,
+        Auto = 1,
+        Loop = 2,
+        Unique = 3,
+        Node = 4,
+        KindMask = 7,
+        ReservedInNestedScopes = 8,
+        Optimistic = 16,
+        FileLevel = 32
+    }
     interface Identifier extends PrimaryExpression, Declaration {
         kind: SyntaxKind.Identifier;
         /**
@@ -498,15 +1069,23 @@ declare namespace ts {
          */
         escapedText: __String;
         originalKeywordKind?: SyntaxKind;
+        autoGenerateFlags?: GeneratedIdentifierFlags;
+        autoGenerateId?: number;
         isInJSDocNamespace?: boolean;
+        typeArguments?: NodeArray<TypeNode | TypeParameterDeclaration>;
+        jsdocDotPos?: number;
     }
     interface TransientIdentifier extends Identifier {
         resolvedSymbol: Symbol;
     }
+    interface GeneratedIdentifier extends Identifier {
+        autoGenerateFlags: GeneratedIdentifierFlags;
+    }
     interface QualifiedName extends Node {
         kind: SyntaxKind.QualifiedName;
         left: EntityName;
         right: Identifier;
+        jsdocDotPos?: number;
     }
     type EntityName = Identifier | QualifiedName;
     type PropertyName = Identifier | StringLiteral | NumericLiteral | ComputedPropertyName;
@@ -517,6 +1096,12 @@ declare namespace ts {
     interface NamedDeclaration extends Declaration {
         name?: DeclarationName;
     }
+    interface DynamicNamedDeclaration extends NamedDeclaration {
+        name: ComputedPropertyName;
+    }
+    interface LateBoundDeclaration extends DynamicNamedDeclaration {
+        name: LateBoundName;
+    }
     interface DeclarationStatement extends NamedDeclaration, Statement {
         name?: Identifier | StringLiteral | NumericLiteral;
     }
@@ -524,6 +1109,9 @@ declare namespace ts {
         kind: SyntaxKind.ComputedPropertyName;
         expression: Expression;
     }
+    interface LateBoundName extends ComputedPropertyName {
+        expression: EntityNameExpression;
+    }
     interface Decorator extends Node {
         kind: SyntaxKind.Decorator;
         parent: NamedDeclaration;
@@ -543,6 +1131,7 @@ declare namespace ts {
         typeParameters?: NodeArray<TypeParameterDeclaration>;
         parameters: NodeArray<ParameterDeclaration>;
         type?: TypeNode;
+        typeArguments?: NodeArray<TypeNode>;
     }
     type SignatureDeclaration = CallSignatureDeclaration | ConstructSignatureDeclaration | MethodSignature | IndexSignatureDeclaration | FunctionTypeNode | ConstructorTypeNode | JSDocFunctionType | FunctionDeclaration | MethodDeclaration | ConstructorDeclaration | AccessorDeclaration | FunctionExpression | ArrowFunction;
     interface CallSignatureDeclaration extends SignatureDeclarationBase, TypeElement {
@@ -582,6 +1171,7 @@ declare namespace ts {
         name: BindingName;
         initializer?: Expression;
     }
+    type BindingElementGrandparent = BindingElement["parent"]["parent"];
     interface PropertySignature extends TypeElement, JSDocContainer {
         kind: SyntaxKind.PropertySignature;
         name: PropertyName;
@@ -676,6 +1266,7 @@ declare namespace ts {
         kind: SyntaxKind.Constructor;
         parent: ClassLikeDeclaration;
         body?: FunctionBody;
+        returnFlowNode?: FlowNode;
     }
     /** For when we encounter a semicolon in a class declaration. ES6 allows these as class elements. */
     interface SemicolonClassElement extends ClassElement {
@@ -711,6 +1302,11 @@ declare namespace ts {
         argument: TypeNode;
         qualifier?: EntityName;
     }
+    type LiteralImportTypeNode = ImportTypeNode & {
+        argument: LiteralTypeNode & {
+            literal: StringLiteral;
+        };
+    };
     interface ThisTypeNode extends TypeNode {
         kind: SyntaxKind.ThisType;
     }
@@ -784,6 +1380,9 @@ declare namespace ts {
         operator: SyntaxKind.KeyOfKeyword | SyntaxKind.UniqueKeyword;
         type: TypeNode;
     }
+    interface UniqueTypeOperatorNode extends TypeOperatorNode {
+        operator: SyntaxKind.UniqueKeyword;
+    }
     interface IndexedAccessTypeNode extends TypeNode {
         kind: SyntaxKind.IndexedAccessType;
         objectType: TypeNode;
@@ -802,6 +1401,9 @@ declare namespace ts {
     }
     interface StringLiteral extends LiteralExpression {
         kind: SyntaxKind.StringLiteral;
+        textSourceNode?: Identifier | StringLiteralLike | NumericLiteral;
+        /** Note: this is only set when synthesizing a node, not during parsing. */
+        singleQuote?: boolean;
     }
     type StringLiteralLike = StringLiteral | NoSubstitutionTemplateLiteral;
     interface Expression extends Node {
@@ -959,8 +1561,24 @@ declare namespace ts {
     interface NoSubstitutionTemplateLiteral extends LiteralExpression {
         kind: SyntaxKind.NoSubstitutionTemplateLiteral;
     }
+    enum TokenFlags {
+        None = 0,
+        PrecedingLineBreak = 1,
+        PrecedingJSDocComment = 2,
+        Unterminated = 4,
+        ExtendedUnicodeEscape = 8,
+        Scientific = 16,
+        Octal = 32,
+        HexSpecifier = 64,
+        BinarySpecifier = 128,
+        OctalSpecifier = 256,
+        ContainsSeparator = 512,
+        BinaryOrOctalSpecifier = 384,
+        NumericLiteralFlags = 1008
+    }
     interface NumericLiteral extends LiteralExpression {
         kind: SyntaxKind.NumericLiteral;
+        numericLiteralFlags: TokenFlags;
     }
     interface TemplateHead extends LiteralLikeNode {
         kind: SyntaxKind.TemplateHead;
@@ -993,6 +1611,7 @@ declare namespace ts {
     interface ArrayLiteralExpression extends PrimaryExpression {
         kind: SyntaxKind.ArrayLiteralExpression;
         elements: NodeArray<Expression>;
+        multiLine?: boolean;
     }
     interface SpreadElement extends Expression {
         kind: SyntaxKind.SpreadElement;
@@ -1010,6 +1629,7 @@ declare namespace ts {
     }
     interface ObjectLiteralExpression extends ObjectLiteralExpressionBase<ObjectLiteralElementLike> {
         kind: SyntaxKind.ObjectLiteralExpression;
+        multiLine?: boolean;
     }
     type EntityNameExpression = Identifier | PropertyAccessEntityNameExpression;
     type EntityNameOrEntityNameExpression = EntityName | EntityNameExpression;
@@ -1158,6 +1778,12 @@ declare namespace ts {
     interface NotEmittedStatement extends Statement {
         kind: SyntaxKind.NotEmittedStatement;
     }
+    /**
+     * Marks the end of transformed declaration to properly emit exports.
+     */
+    interface EndOfDeclarationMarker extends Statement {
+        kind: SyntaxKind.EndOfDeclarationMarker;
+    }
     /**
      * A list of comma-separated expressions. This node is only created by transformations.
      */
@@ -1165,6 +1791,12 @@ declare namespace ts {
         kind: SyntaxKind.CommaListExpression;
         elements: NodeArray<Expression>;
     }
+    /**
+     * Marks the beginning of a merged transformed declaration.
+     */
+    interface MergeDeclarationMarker extends Statement {
+        kind: SyntaxKind.MergeDeclarationMarker;
+    }
     interface EmptyStatement extends Statement {
         kind: SyntaxKind.EmptyStatement;
     }
@@ -1179,6 +1811,7 @@ declare namespace ts {
     interface Block extends Statement {
         kind: SyntaxKind.Block;
         statements: NodeArray<Statement>;
+        multiLine?: boolean;
     }
     interface VariableStatement extends Statement, JSDocContainer {
         kind: SyntaxKind.VariableStatement;
@@ -1188,6 +1821,9 @@ declare namespace ts {
         kind: SyntaxKind.ExpressionStatement;
         expression: Expression;
     }
+    interface PrologueDirective extends ExpressionStatement {
+        expression: StringLiteral;
+    }
     interface IfStatement extends Statement {
         kind: SyntaxKind.IfStatement;
         expression: Expression;
@@ -1345,6 +1981,9 @@ declare namespace ts {
     }
     type ModuleName = Identifier | StringLiteral;
     type ModuleBody = NamespaceBody | JSDocNamespaceBody;
+    interface AmbientModuleDeclaration extends ModuleDeclaration {
+        body?: ModuleBlock;
+    }
     interface ModuleDeclaration extends DeclarationStatement, JSDocContainer {
         kind: SyntaxKind.ModuleDeclaration;
         parent: ModuleBody | SourceFile;
@@ -1642,12 +2281,36 @@ declare namespace ts {
         path: string;
         name?: string;
     }
+    /**
+     * Subset of properties from SourceFile that are used in multiple utility functions
+     */
+    interface SourceFileLike {
+        readonly text: string;
+        lineMap?: ReadonlyArray<number>;
+    }
+    interface RedirectInfo {
+        /** Source file this redirects to. */
+        readonly redirectTarget: SourceFile;
+        /**
+         * Source file for the duplicate package. This will not be used by the Program,
+         * but we need to keep this around so we can watch for changes in underlying.
+         */
+        readonly unredirected: SourceFile;
+    }
     interface SourceFile extends Declaration {
         kind: SyntaxKind.SourceFile;
         statements: NodeArray<Statement>;
         endOfFileToken: Token<SyntaxKind.EndOfFileToken>;
         fileName: string;
+        path: Path;
         text: string;
+        resolvedPath: Path;
+        /**
+         * If two source files are for the same version of the same package, one will redirect to the other.
+         * (See `createRedirectSourceFile` in program.ts.)
+         * The redirect will have this set. The redirected-to source file will be in `redirectTargetsSet`.
+         */
+        redirectInfo?: RedirectInfo;
         amdDependencies: ReadonlyArray<AmdDependency>;
         moduleName?: string;
         referencedFiles: ReadonlyArray<FileReference>;
@@ -1655,6 +2318,7 @@ declare namespace ts {
         libReferenceDirectives: ReadonlyArray<FileReference>;
         languageVariant: LanguageVariant;
         isDeclarationFile: boolean;
+        renamedDependencies?: ReadonlyMap<string>;
         /**
          * lib.d.ts should have a reference comment like
          *
@@ -1665,11 +2329,49 @@ declare namespace ts {
          */
         hasNoDefaultLib: boolean;
         languageVersion: ScriptTarget;
+        scriptKind: ScriptKind;
+        /**
+         * The first "most obvious" node that makes a file an external module.
+         * This is intended to be the first top-level import/export,
+         * but could be arbitrarily nested (e.g. `import.meta`).
+         */
+        externalModuleIndicator?: Node;
+        commonJsModuleIndicator?: Node;
+        identifiers: Map<string>;
+        nodeCount: number;
+        identifierCount: number;
+        symbolCount: number;
+        parseDiagnostics: DiagnosticWithLocation[];
+        bindDiagnostics: DiagnosticWithLocation[];
+        bindSuggestionDiagnostics?: DiagnosticWithLocation[];
+        jsDocDiagnostics?: DiagnosticWithLocation[];
+        additionalSyntacticDiagnostics?: ReadonlyArray<DiagnosticWithLocation>;
+        lineMap: ReadonlyArray<number>;
+        classifiableNames?: ReadonlyUnderscoreEscapedMap<true>;
+        resolvedModules?: Map<ResolvedModuleFull | undefined>;
+        resolvedTypeReferenceDirectiveNames: Map<ResolvedTypeReferenceDirective>;
+        imports: ReadonlyArray<StringLiteralLike>;
+        /**
+         * When a file's references are redirected due to project reference directives,
+         * the original names of the references are stored in this array
+         */
+        redirectedReferences?: ReadonlyArray<string>;
+        moduleAugmentations: ReadonlyArray<StringLiteral | Identifier>;
+        patternAmbientModules?: PatternAmbientModule[];
+        ambientModuleNames: ReadonlyArray<string>;
+        checkJsDirective?: CheckJsDirective;
+        version: string;
+        pragmas: PragmaMap;
+        localJsxNamespace?: __String;
+        localJsxFactory?: EntityName;
     }
     interface Bundle extends Node {
         kind: SyntaxKind.Bundle;
         prepends: ReadonlyArray<InputFiles | UnparsedSource>;
         sourceFiles: ReadonlyArray<SourceFile>;
+        syntheticFileReferences?: ReadonlyArray<FileReference>;
+        syntheticTypeReferences?: ReadonlyArray<FileReference>;
+        hasNoDefaultLib?: boolean;
     }
     interface InputFiles extends Node {
         kind: SyntaxKind.InputFiles;
@@ -1730,6 +2432,11 @@ declare namespace ts {
          * Get a list of files in the program
          */
         getSourceFiles(): ReadonlyArray<SourceFile>;
+        /**
+         * Get a list of file names that were passed to 'createProgram' or referenced in a
+         * program source file but could not be located.
+         */
+        getMissingFilePaths(): ReadonlyArray<Path>;
         /**
          * Emits the JavaScript and declaration files.  If targetSourceFile is not specified, then
          * the JavaScript and declaration files will be produced for all the files in this program.
@@ -1748,17 +2455,44 @@ declare namespace ts {
         getSemanticDiagnostics(sourceFile?: SourceFile, cancellationToken?: CancellationToken): ReadonlyArray<Diagnostic>;
         getDeclarationDiagnostics(sourceFile?: SourceFile, cancellationToken?: CancellationToken): ReadonlyArray<DiagnosticWithLocation>;
         getConfigFileParsingDiagnostics(): ReadonlyArray<Diagnostic>;
+        getSuggestionDiagnostics(sourceFile: SourceFile, cancellationToken?: CancellationToken): ReadonlyArray<DiagnosticWithLocation>;
         /**
          * Gets a type checker that can be used to semantically analyze source files in the program.
          */
         getTypeChecker(): TypeChecker;
+        getCommonSourceDirectory(): string;
+        getDiagnosticsProducingTypeChecker(): TypeChecker;
+        dropDiagnosticsProducingTypeChecker(): void;
+        getClassifiableNames(): UnderscoreEscapedMap<true>;
+        getNodeCount(): number;
+        getIdentifierCount(): number;
+        getSymbolCount(): number;
+        getTypeCount(): number;
+        getFileProcessingDiagnostics(): DiagnosticCollection;
+        getResolvedTypeReferenceDirectives(): Map<ResolvedTypeReferenceDirective>;
         isSourceFileFromExternalLibrary(file: SourceFile): boolean;
+        isSourceFileDefaultLibrary(file: SourceFile): boolean;
+        structureIsReused?: StructureIsReused;
+        getSourceFileFromReference(referencingFile: SourceFile, ref: FileReference): SourceFile | undefined;
+        getLibFileFromReference(ref: FileReference): SourceFile | undefined;
+        /** Given a source file, get the name of the package it was imported from. */
+        sourceFileToPackageName: Map<string>;
+        /** Set of all source files that some other source file redirects to. */
+        redirectTargetsSet: Map<true>;
+        /** Is the file emitted file */
+        isEmittedFile(file: string): boolean;
+        getResolvedModuleWithFailedLookupLocationsFromCache(moduleName: string, containingFile: string): ResolvedModuleWithFailedLookupLocations | undefined;
         getProjectReferences(): (ResolvedProjectReference | undefined)[] | undefined;
     }
     interface ResolvedProjectReference {
         commandLine: ParsedCommandLine;
         sourceFile: SourceFile;
     }
+    enum StructureIsReused {
+        Not = 0,
+        SafeModules = 1,
+        Completely = 2
+    }
     interface CustomTransformers {
         /** Custom transformers to evaluate before built-in .js transformations. */
         before?: TransformerFactory<SourceFile>[];
@@ -1804,6 +2538,13 @@ declare namespace ts {
         /** Contains declaration emit diagnostics */
         diagnostics: ReadonlyArray<Diagnostic>;
         emittedFiles?: string[];
+        sourceMaps?: SourceMapData[];
+    }
+    interface TypeCheckerHost {
+        getCompilerOptions(): CompilerOptions;
+        getSourceFiles(): ReadonlyArray<SourceFile>;
+        getSourceFile(fileName: string): SourceFile | undefined;
+        getResolvedTypeReferenceDirectives(): ReadonlyMap<ResolvedTypeReferenceDirective>;
     }
     interface TypeChecker {
         getTypeOfSymbolAtLocation(symbol: Symbol, node: Node): Type;
@@ -1817,10 +2558,16 @@ declare namespace ts {
         getBaseTypeOfLiteralType(type: Type): Type;
         getWidenedType(type: Type): Type;
         getReturnTypeOfSignature(signature: Signature): Type;
+        /**
+         * Gets the type of a parameter at a given position in a signature.
+         * Returns `any` if the index is not valid.
+         */
+        getParameterType(signature: Signature, parameterIndex: number): Type;
         getNullableType(type: Type, flags: TypeFlags): Type;
         getNonNullableType(type: Type): Type;
         /** Note that the resulting nodes cannot be checked. */
         typeToTypeNode(type: Type, enclosingDeclaration?: Node, flags?: NodeBuilderFlags): TypeNode | undefined;
+        typeToTypeNode(type: Type, enclosingDeclaration?: Node, flags?: NodeBuilderFlags, tracker?: SymbolTracker): TypeNode | undefined;
         /** Note that the resulting nodes cannot be checked. */
         signatureToSignatureDeclaration(signature: Signature, kind: SyntaxKind, enclosingDeclaration?: Node, flags?: NodeBuilderFlags): (SignatureDeclaration & {
             typeArguments?: NodeArray<TypeNode>;
@@ -1862,6 +2609,10 @@ declare namespace ts {
         typeToString(type: Type, enclosingDeclaration?: Node, flags?: TypeFormatFlags): string;
         symbolToString(symbol: Symbol, enclosingDeclaration?: Node, meaning?: SymbolFlags, flags?: SymbolFormatFlags): string;
         typePredicateToString(predicate: TypePredicate, enclosingDeclaration?: Node, flags?: TypeFormatFlags): string;
+        writeSignature(signature: Signature, enclosingDeclaration?: Node, flags?: TypeFormatFlags, kind?: SignatureKind, writer?: EmitTextWriter): string;
+        writeType(type: Type, enclosingDeclaration?: Node, flags?: TypeFormatFlags, writer?: EmitTextWriter): string;
+        writeSymbol(symbol: Symbol, enclosingDeclaration?: Node, meaning?: SymbolFlags, flags?: SymbolFormatFlags, writer?: EmitTextWriter): string;
+        writeTypePredicate(predicate: TypePredicate, enclosingDeclaration?: Node, flags?: TypeFormatFlags, writer?: EmitTextWriter): string;
         /**
          * @deprecated Use the createX factory functions or XToY typechecker methods and `createPrinter` or the `xToString` methods instead
          * This will be removed in a future version.
@@ -1871,6 +2622,9 @@ declare namespace ts {
         getAugmentedPropertiesOfType(type: Type): Symbol[];
         getRootSymbols(symbol: Symbol): Symbol[];
         getContextualType(node: Expression): Type | undefined;
+        getContextualTypeForArgumentAtIndex(call: CallLikeExpression, argIndex: number): Type | undefined;
+        getContextualTypeForJsxAttribute(attribute: JsxAttribute | JsxSpreadAttribute): Type | undefined;
+        isContextSensitive(node: Expression | MethodDeclaration | ObjectLiteralElementLike | JsxAttributeLike): boolean;
         /**
          * returns unknownSignature in the case of an error.
          * returns undefined if the node is not valid.
@@ -1882,22 +2636,91 @@ declare namespace ts {
         isUndefinedSymbol(symbol: Symbol): boolean;
         isArgumentsSymbol(symbol: Symbol): boolean;
         isUnknownSymbol(symbol: Symbol): boolean;
+        getMergedSymbol(symbol: Symbol): Symbol;
         getConstantValue(node: EnumMember | PropertyAccessExpression | ElementAccessExpression): string | number | undefined;
         isValidPropertyAccess(node: PropertyAccessExpression | QualifiedName | ImportTypeNode, propertyName: string): boolean;
+        /** Exclude accesses to private properties or methods with a `this` parameter that `type` doesn't satisfy. */
+        isValidPropertyAccessForCompletions(node: PropertyAccessExpression | ImportTypeNode, type: Type, property: Symbol): boolean;
         /** Follow all aliases to get the original symbol. */
         getAliasedSymbol(symbol: Symbol): Symbol;
+        /** Follow a *single* alias to get the immediately aliased symbol. */
+        getImmediateAliasedSymbol(symbol: Symbol): Symbol | undefined;
         getExportsOfModule(moduleSymbol: Symbol): Symbol[];
+        /** Unlike `getExportsOfModule`, this includes properties of an `export =` value. */
+        getExportsAndPropertiesOfModule(moduleSymbol: Symbol): Symbol[];
         getAllAttributesTypeFromJsxOpeningLikeElement(elementNode: JsxOpeningLikeElement): Type | undefined;
         getJsxIntrinsicTagNamesAt(location: Node): Symbol[];
         isOptionalParameter(node: ParameterDeclaration): boolean;
         getAmbientModules(): Symbol[];
         tryGetMemberInModuleExports(memberName: string, moduleSymbol: Symbol): Symbol | undefined;
+        /**
+         * Unlike `tryGetMemberInModuleExports`, this includes properties of an `export =` value.
+         * Does *not* return properties of primitive types.
+         */
+        tryGetMemberInModuleExportsAndProperties(memberName: string, moduleSymbol: Symbol): Symbol | undefined;
         getApparentType(type: Type): Type;
         getSuggestionForNonexistentProperty(node: Identifier, containingType: Type): string | undefined;
         getSuggestionForNonexistentSymbol(location: Node, name: string, meaning: SymbolFlags): string | undefined;
         getSuggestionForNonexistentModule(node: Identifier, target: Symbol): string | undefined;
         getBaseConstraintOfType(type: Type): Type | undefined;
         getDefaultFromTypeParameter(type: Type): Type | undefined;
+        getAnyType(): Type;
+        getStringType(): Type;
+        getNumberType(): Type;
+        getBooleanType(): Type;
+        getFalseType(): Type;
+        getTrueType(): Type;
+        getVoidType(): Type;
+        getUndefinedType(): Type;
+        getNullType(): Type;
+        getESSymbolType(): Type;
+        getNeverType(): Type;
+        getUnionType(types: Type[], subtypeReduction?: UnionReduction): Type;
+        createArrayType(elementType: Type): Type;
+        createPromiseType(type: Type): Type;
+        createAnonymousType(symbol: Symbol, members: SymbolTable, callSignatures: Signature[], constructSignatures: Signature[], stringIndexInfo: IndexInfo | undefined, numberIndexInfo: IndexInfo | undefined): Type;
+        createSignature(declaration: SignatureDeclaration, typeParameters: TypeParameter[] | undefined, thisParameter: Symbol | undefined, parameters: Symbol[], resolvedReturnType: Type, typePredicate: TypePredicate | undefined, minArgumentCount: number, hasRestParameter: boolean, hasLiteralTypes: boolean): Signature;
+        createSymbol(flags: SymbolFlags, name: __String): TransientSymbol;
+        createIndexInfo(type: Type, isReadonly: boolean, declaration?: SignatureDeclaration): IndexInfo;
+        isSymbolAccessible(symbol: Symbol, enclosingDeclaration: Node | undefined, meaning: SymbolFlags, shouldComputeAliasToMarkVisible: boolean): SymbolAccessibilityResult;
+        tryFindAmbientModuleWithoutAugmentations(moduleName: string): Symbol | undefined;
+        getSymbolWalker(accept?: (symbol: Symbol) => boolean): SymbolWalker;
+        getDiagnostics(sourceFile?: SourceFile, cancellationToken?: CancellationToken): Diagnostic[];
+        getGlobalDiagnostics(): Diagnostic[];
+        getEmitResolver(sourceFile?: SourceFile, cancellationToken?: CancellationToken): EmitResolver;
+        getNodeCount(): number;
+        getIdentifierCount(): number;
+        getSymbolCount(): number;
+        getTypeCount(): number;
+        isArrayLikeType(type: Type): boolean;
+        /**
+         * For a union, will include a property if it's defined in *any* of the member types.
+         * So for `{ a } | { b }`, this will include both `a` and `b`.
+         * Does not include properties of primitive types.
+         */
+        getAllPossiblePropertiesOfTypes(type: ReadonlyArray<Type>): Symbol[];
+        resolveName(name: string, location: Node, meaning: SymbolFlags, excludeGlobals: boolean): Symbol | undefined;
+        getJsxNamespace(location?: Node): string;
+        /**
+         * Note that this will return undefined in the following case:
+         *     // a.ts
+         *     export namespace N { export class C { } }
+         *     // b.ts
+         *     <<enclosingDeclaration>>
+         * Where `C` is the symbol we're looking for.
+         * This should be called in a loop climbing parents of the symbol, so we'll get `N`.
+         */
+        getAccessibleSymbolChain(symbol: Symbol, enclosingDeclaration: Node | undefined, meaning: SymbolFlags, useOnlyExternalAliasing: boolean): Symbol[] | undefined;
+        getTypePredicateOfSignature(signature: Signature): TypePredicate;
+        resolveExternalModuleSymbol(symbol: Symbol): Symbol;
+        /** @param node A location where we might consider accessing `this`. Not necessarily a ThisExpression. */
+        tryGetThisTypeAt(node: Node): Type | undefined;
+        getTypeArgumentConstraint(node: TypeNode): Type | undefined;
+        /**
+         * Does *not* get *all* suggestion diagnostics, just the ones that were convenient to report in the checker.
+         * Others are added in computeSuggestionDiagnostics.
+         */
+        getSuggestionDiagnostics(file: SourceFile, cancellationToken?: CancellationToken): ReadonlyArray<DiagnosticWithLocation>;
         /**
          * Depending on the operation performed, it may be appropriate to throw away the checker
          * if the cancellation token is triggered. Typically, if it is used for error checking
@@ -1905,6 +2728,11 @@ declare namespace ts {
          */
         runWithCancellationToken<T>(token: CancellationToken, cb: (checker: TypeChecker) => T): T;
     }
+    enum UnionReduction {
+        None = 0,
+        Literal = 1,
+        Subtype = 2
+    }
     enum NodeBuilderFlags {
         None = 0,
         NoTruncation = 1,
@@ -1965,6 +2793,18 @@ declare namespace ts {
         AllowAnyNodeKind = 4,
         UseAliasDefinedOutsideCurrentScope = 8
     }
+    interface SymbolWalker {
+        /** Note: Return values are not ordered. */
+        walkType(root: Type): {
+            visitedTypes: ReadonlyArray<Type>;
+            visitedSymbols: ReadonlyArray<Symbol>;
+        };
+        /** Note: Return values are not ordered. */
+        walkSymbol(root: Symbol): {
+            visitedTypes: ReadonlyArray<Type>;
+            visitedSymbols: ReadonlyArray<Symbol>;
+        };
+    }
     /**
      * @deprecated
      */
@@ -1998,6 +2838,15 @@ declare namespace ts {
         decreaseIndent(): void;
         clear(): void;
     }
+    enum SymbolAccessibility {
+        Accessible = 0,
+        NotAccessible = 1,
+        CannotBeNamed = 2
+    }
+    enum SyntheticSymbolKind {
+        UnionOrIntersection = 0,
+        Spread = 1
+    }
     enum TypePredicateKind {
         This = 0,
         Identifier = 1
@@ -2015,6 +2864,88 @@ declare namespace ts {
         parameterIndex: number;
     }
     type TypePredicate = IdentifierTypePredicate | ThisTypePredicate;
+    type AnyImportSyntax = ImportDeclaration | ImportEqualsDeclaration;
+    type AnyImportOrReExport = AnyImportSyntax | ExportDeclaration;
+    interface ValidImportTypeNode extends ImportTypeNode {
+        argument: LiteralTypeNode & {
+            literal: StringLiteral;
+        };
+    }
+    type AnyValidImportOrReExport = (ImportDeclaration | ExportDeclaration) & {
+        moduleSpecifier: StringLiteral;
+    } | ImportEqualsDeclaration & {
+        moduleReference: ExternalModuleReference & {
+            expression: StringLiteral;
+        };
+    } | RequireOrImportCall | ValidImportTypeNode;
+    type RequireOrImportCall = CallExpression & {
+        arguments: [StringLiteralLike];
+    };
+    type LateVisibilityPaintedStatement = AnyImportSyntax | VariableStatement | ClassDeclaration | FunctionDeclaration | ModuleDeclaration | TypeAliasDeclaration | InterfaceDeclaration | EnumDeclaration;
+    interface SymbolVisibilityResult {
+        accessibility: SymbolAccessibility;
+        aliasesToMakeVisible?: LateVisibilityPaintedStatement[];
+        errorSymbolName?: string;
+        errorNode?: Node;
+    }
+    interface SymbolAccessibilityResult extends SymbolVisibilityResult {
+        errorModuleName?: string;
+    }
+    interface AllAccessorDeclarations {
+        firstAccessor: AccessorDeclaration;
+        secondAccessor: AccessorDeclaration | undefined;
+        getAccessor: AccessorDeclaration | undefined;
+        setAccessor: AccessorDeclaration | undefined;
+    }
+    /** Indicates how to serialize the name for a TypeReferenceNode when emitting decorator metadata */
+    enum TypeReferenceSerializationKind {
+        Unknown = 0,
+        TypeWithConstructSignatureAndValue = 1,
+        VoidNullableOrNeverType = 2,
+        NumberLikeType = 3,
+        StringLikeType = 4,
+        BooleanType = 5,
+        ArrayLikeType = 6,
+        ESSymbolType = 7,
+        Promise = 8,
+        TypeWithCallSignature = 9,
+        ObjectType = 10
+    }
+    interface EmitResolver {
+        hasGlobalName(name: string): boolean;
+        getReferencedExportContainer(node: Identifier, prefixLocals?: boolean): SourceFile | ModuleDeclaration | EnumDeclaration | undefined;
+        getReferencedImportDeclaration(node: Identifier): Declaration | undefined;
+        getReferencedDeclarationWithCollidingName(node: Identifier): Declaration | undefined;
+        isDeclarationWithCollidingName(node: Declaration): boolean;
+        isValueAliasDeclaration(node: Node): boolean;
+        isReferencedAliasDeclaration(node: Node, checkChildren?: boolean): boolean;
+        isTopLevelValueImportEqualsWithEntityName(node: ImportEqualsDeclaration): boolean;
+        getNodeCheckFlags(node: Node): NodeCheckFlags;
+        isDeclarationVisible(node: Declaration | AnyImportSyntax): boolean;
+        isLateBound(node: Declaration): node is LateBoundDeclaration;
+        collectLinkedAliases(node: Identifier): Node[] | undefined;
+        isImplementationOfOverload(node: FunctionLike): boolean | undefined;
+        isRequiredInitializedParameter(node: ParameterDeclaration): boolean;
+        isOptionalUninitializedParameterProperty(node: ParameterDeclaration): boolean;
+        createTypeOfDeclaration(declaration: AccessorDeclaration | VariableLikeDeclaration, enclosingDeclaration: Node, flags: NodeBuilderFlags, tracker: SymbolTracker, addUndefined?: boolean): TypeNode | undefined;
+        createReturnTypeOfSignatureDeclaration(signatureDeclaration: SignatureDeclaration, enclosingDeclaration: Node, flags: NodeBuilderFlags, tracker: SymbolTracker): TypeNode | undefined;
+        createTypeOfExpression(expr: Expression, enclosingDeclaration: Node, flags: NodeBuilderFlags, tracker: SymbolTracker): TypeNode | undefined;
+        createLiteralConstValue(node: VariableDeclaration | PropertyDeclaration | PropertySignature | ParameterDeclaration): Expression;
+        isSymbolAccessible(symbol: Symbol, enclosingDeclaration: Node | undefined, meaning: SymbolFlags | undefined, shouldComputeAliasToMarkVisible: boolean): SymbolAccessibilityResult;
+        isEntityNameVisible(entityName: EntityNameOrEntityNameExpression, enclosingDeclaration: Node): SymbolVisibilityResult;
+        getConstantValue(node: EnumMember | PropertyAccessExpression | ElementAccessExpression): string | number | undefined;
+        getReferencedValueDeclaration(reference: Identifier): Declaration | undefined;
+        getTypeReferenceSerializationKind(typeName: EntityName, location?: Node): TypeReferenceSerializationKind;
+        isOptionalParameter(node: ParameterDeclaration): boolean;
+        moduleExportsSomeValue(moduleReferenceExpression: Expression): boolean;
+        isArgumentsLocalBinding(node: Identifier): boolean;
+        getExternalModuleFileFromDeclaration(declaration: ImportEqualsDeclaration | ImportDeclaration | ExportDeclaration | ModuleDeclaration | ImportTypeNode): SourceFile | undefined;
+        getTypeReferenceDirectivesForEntityName(name: EntityNameOrEntityNameExpression): string[] | undefined;
+        getTypeReferenceDirectivesForSymbol(symbol: Symbol, meaning?: SymbolFlags): string[] | undefined;
+        isLiteralConstDeclaration(node: VariableDeclaration | PropertyDeclaration | PropertySignature | ParameterDeclaration): boolean;
+        getJsxFactoryEntity(location?: Node): EntityName | undefined;
+        getAllAccessorDeclarations(declaration: AccessorDeclaration): AllAccessorDeclarations;
+    }
     enum SymbolFlags {
         None = 0,
         FunctionScopedVariable = 1,
@@ -2044,6 +2975,7 @@ declare namespace ts {
         Optional = 16777216,
         Transient = 33554432,
         JSContainer = 67108864,
+        All = 67108863,
         Enum = 384,
         Variable = 3,
         Value = 67216319,
@@ -2071,11 +3003,13 @@ declare namespace ts {
         AliasExcludes = 2097152,
         ModuleMember = 2623475,
         ExportHasLocal = 944,
-        HasExports = 1952,
+        HasExports = 1955,
         HasMembers = 6240,
         BlockScoped = 418,
         PropertyOrAccessor = 98308,
-        ClassMember = 106500
+        ClassMember = 106500,
+        Classifiable = 2885600,
+        LateBindingContainer = 6240
     }
     interface Symbol {
         flags: SymbolFlags;
@@ -2085,6 +3019,70 @@ declare namespace ts {
         members?: SymbolTable;
         exports?: SymbolTable;
         globalExports?: SymbolTable;
+        id?: number;
+        mergeId?: number;
+        parent?: Symbol;
+        exportSymbol?: Symbol;
+        nameType?: Type;
+        constEnumOnlyModule?: boolean;
+        isReferenced?: SymbolFlags;
+        isReplaceableByMethod?: boolean;
+        isAssigned?: boolean;
+    }
+    interface SymbolLinks {
+        immediateTarget?: Symbol;
+        target?: Symbol;
+        type?: Type;
+        uniqueESSymbolType?: Type;
+        declaredType?: Type;
+        typeParameters?: TypeParameter[];
+        outerTypeParameters?: TypeParameter[];
+        inferredClassType?: Type;
+        instantiations?: Map<Type>;
+        mapper?: TypeMapper;
+        referenced?: boolean;
+        containingType?: UnionOrIntersectionType;
+        leftSpread?: Symbol;
+        rightSpread?: Symbol;
+        syntheticOrigin?: Symbol;
+        isDiscriminantProperty?: boolean;
+        resolvedExports?: SymbolTable;
+        resolvedMembers?: SymbolTable;
+        exportsChecked?: boolean;
+        typeParametersChecked?: boolean;
+        isDeclarationWithCollidingName?: boolean;
+        bindingElement?: BindingElement;
+        exportsSomeValue?: boolean;
+        enumKind?: EnumKind;
+        originatingImport?: ImportDeclaration | ImportCall;
+        lateSymbol?: Symbol;
+    }
+    enum EnumKind {
+        Numeric = 0,
+        Literal = 1
+    }
+    enum CheckFlags {
+        Instantiated = 1,
+        SyntheticProperty = 2,
+        SyntheticMethod = 4,
+        Readonly = 8,
+        Partial = 16,
+        HasNonUniformType = 32,
+        ContainsPublic = 64,
+        ContainsProtected = 128,
+        ContainsPrivate = 256,
+        ContainsStatic = 512,
+        Late = 1024,
+        ReverseMapped = 2048,
+        Synthetic = 6
+    }
+    interface TransientSymbol extends Symbol, SymbolLinks {
+        checkFlags: CheckFlags;
+        isRestParameter?: boolean;
+    }
+    interface ReverseMappedSymbol extends TransientSymbol {
+        propertyType: Type;
+        mappedType: MappedType;
     }
     enum InternalSymbolName {
         Call = "__call",
@@ -2135,6 +3133,53 @@ declare namespace ts {
     }
     /** SymbolTable based on ES6 Map interface. */
     type SymbolTable = UnderscoreEscapedMap<Symbol>;
+    /** Used to track a `declare module "foo*"`-like declaration. */
+    interface PatternAmbientModule {
+        pattern: Pattern;
+        symbol: Symbol;
+    }
+    enum NodeCheckFlags {
+        TypeChecked = 1,
+        LexicalThis = 2,
+        CaptureThis = 4,
+        CaptureNewTarget = 8,
+        SuperInstance = 256,
+        SuperStatic = 512,
+        ContextChecked = 1024,
+        AsyncMethodWithSuper = 2048,
+        AsyncMethodWithSuperBinding = 4096,
+        CaptureArguments = 8192,
+        EnumValuesComputed = 16384,
+        LexicalModuleMergesWithClass = 32768,
+        LoopWithCapturedBlockScopedBinding = 65536,
+        CapturedBlockScopedBinding = 131072,
+        BlockScopedBindingInLoop = 262144,
+        ClassWithBodyScopedClassBinding = 524288,
+        BodyScopedClassBinding = 1048576,
+        NeedsLoopOutParameter = 2097152,
+        AssignmentsMarked = 4194304,
+        ClassWithConstructorReference = 8388608,
+        ConstructorReferenceInClass = 16777216
+    }
+    interface NodeLinks {
+        flags: NodeCheckFlags;
+        resolvedType?: Type;
+        resolvedSignature?: Signature;
+        resolvedSignatures?: Map<Signature[]>;
+        resolvedSymbol?: Symbol;
+        resolvedIndexInfo?: IndexInfo;
+        maybeTypePredicate?: boolean;
+        enumMemberValue?: string | number;
+        isVisible?: boolean;
+        containsArgumentsReference?: boolean;
+        hasReportedStatementInAmbientContext?: boolean;
+        jsxFlags: JsxFlags;
+        resolvedJsxElementAttributesType?: Type;
+        resolvedJsxElementAllAttributesType?: Type;
+        hasSuperCall?: boolean;
+        superCall?: SuperCall;
+        switchTypes?: Type[];
+    }
     enum TypeFlags {
         Any = 1,
         Unknown = 2,
@@ -2161,16 +3206,28 @@ declare namespace ts {
         Conditional = 4194304,
         Substitution = 8388608,
         NonPrimitive = 16777216,
+        FreshLiteral = 33554432,
+        UnionOfUnitTypes = 67108864,
+        ContainsWideningType = 134217728,
+        ContainsObjectLiteral = 268435456,
+        ContainsAnyFunctionType = 536870912,
+        AnyOrUnknown = 3,
+        Nullable = 24576,
         Literal = 448,
         Unit = 27072,
         StringOrNumberLiteral = 192,
+        StringOrNumberLiteralOrUnique = 2240,
+        DefinitelyFalsy = 29120,
         PossiblyFalsy = 29148,
+        Intrinsic = 16839967,
+        Primitive = 32764,
         StringLike = 68,
         NumberLike = 168,
         BooleanLike = 272,
         EnumLike = 544,
         ESSymbolLike = 3072,
         VoidLike = 12288,
+        DisjointDomains = 16809468,
         UnionOrIntersection = 786432,
         StructuredType = 917504,
         TypeVariable = 2162688,
@@ -2179,15 +3236,29 @@ declare namespace ts {
         Instantiable = 15794176,
         StructuredOrInstantiable = 16711680,
         Narrowable = 33492479,
-        NotUnionOrUnit = 16909315
+        NotUnionOrUnit = 16909315,
+        NotUnit = 16749629,
+        RequiresWidening = 402653184,
+        PropagatingFlags = 939524096,
+        NonWideningType = 134217728,
+        Wildcard = 268435456,
+        EmptyObject = 536870912,
+        ConstructionFlags = 939524096,
+        GenericMappedType = 134217728
     }
     type DestructuringPattern = BindingPattern | ObjectLiteralExpression | ArrayLiteralExpression;
     interface Type {
         flags: TypeFlags;
+        id: number;
+        checker: TypeChecker;
         symbol: Symbol;
         pattern?: DestructuringPattern;
         aliasSymbol?: Symbol;
         aliasTypeArguments?: Type[];
+        wildcardInstantiation?: Type;
+    }
+    interface IntrinsicType extends Type {
+        intrinsicName: string;
     }
     interface LiteralType extends Type {
         value: string | number;
@@ -2231,6 +3302,8 @@ declare namespace ts {
         outerTypeParameters: TypeParameter[] | undefined;
         localTypeParameters: TypeParameter[] | undefined;
         thisType: TypeParameter | undefined;
+        resolvedBaseConstructorType?: Type;
+        resolvedBaseTypes: BaseType[];
     }
     type BaseType = ObjectType | IntersectionType;
     interface InterfaceTypeWithDeclaredMembers extends InterfaceType {
@@ -2254,23 +3327,89 @@ declare namespace ts {
         target: GenericType;
         typeArguments?: Type[];
     }
+    enum Variance {
+        Invariant = 0,
+        Covariant = 1,
+        Contravariant = 2,
+        Bivariant = 3,
+        Independent = 4
+    }
     interface GenericType extends InterfaceType, TypeReference {
+        instantiations: Map<TypeReference>;
+        variances?: Variance[];
     }
     interface UnionOrIntersectionType extends Type {
         types: Type[];
+        propertyCache: SymbolTable;
+        resolvedProperties: Symbol[];
+        resolvedIndexType: IndexType;
+        resolvedStringIndexType: IndexType;
+        resolvedBaseConstraint: Type;
+        couldContainTypeVariables: boolean;
     }
     interface UnionType extends UnionOrIntersectionType {
     }
     interface IntersectionType extends UnionOrIntersectionType {
+        resolvedApparentType: Type;
     }
     type StructuredType = ObjectType | UnionType | IntersectionType;
+    interface AnonymousType extends ObjectType {
+        target?: AnonymousType;
+        mapper?: TypeMapper;
+    }
+    interface MappedType extends AnonymousType {
+        declaration: MappedTypeNode;
+        typeParameter?: TypeParameter;
+        constraintType?: Type;
+        templateType?: Type;
+        modifiersType?: Type;
+    }
     interface EvolvingArrayType extends ObjectType {
         elementType: Type;
         finalArrayType?: Type;
     }
+    interface ReverseMappedType extends ObjectType {
+        source: Type;
+        mappedType: MappedType;
+    }
+    interface ResolvedType extends ObjectType, UnionOrIntersectionType {
+        members: SymbolTable;
+        properties: Symbol[];
+        callSignatures: Signature[];
+        constructSignatures: Signature[];
+        stringIndexInfo?: IndexInfo;
+        numberIndexInfo?: IndexInfo;
+    }
+    interface FreshObjectLiteralType extends ResolvedType {
+        regularType: ResolvedType;
+    }
+    interface IterableOrIteratorType extends ObjectType, UnionType {
+        iteratedTypeOfIterable?: Type;
+        iteratedTypeOfIterator?: Type;
+        iteratedTypeOfAsyncIterable?: Type;
+        iteratedTypeOfAsyncIterator?: Type;
+    }
+    interface PromiseOrAwaitableType extends ObjectType, UnionType {
+        promiseTypeOfPromiseConstructor?: Type;
+        promisedTypeOfPromise?: Type;
+        awaitedTypeOfType?: Type;
+    }
+    interface SyntheticDefaultModuleType extends Type {
+        syntheticType?: Type;
+    }
     interface InstantiableType extends Type {
+        resolvedBaseConstraint?: Type;
+        resolvedIndexType?: IndexType;
+        resolvedStringIndexType?: IndexType;
     }
     interface TypeParameter extends InstantiableType {
+        /** Retrieve using getConstraintFromTypeParameter */
+        constraint?: Type;
+        default?: Type;
+        target?: TypeParameter;
+        mapper?: TypeMapper;
+        isThisType?: boolean;
+        resolvedDefaultType?: Type;
     }
     interface IndexedAccessType extends InstantiableType {
         objectType: Type;
@@ -2281,6 +3420,7 @@ declare namespace ts {
     type TypeVariable = TypeParameter | IndexedAccessType;
     interface IndexType extends InstantiableType {
         type: InstantiableType | UnionOrIntersectionType;
+        stringsOnly: boolean;
     }
     interface ConditionalRoot {
         node: ConditionalTypeNode;
@@ -2301,6 +3441,9 @@ declare namespace ts {
         extendsType: Type;
         resolvedTrueType?: Type;
         resolvedFalseType?: Type;
+        resolvedDefaultConstraint?: Type;
+        mapper?: TypeMapper;
+        combinedMapper?: TypeMapper;
     }
     interface SubstitutionType extends InstantiableType {
         typeVariable: TypeVariable;
@@ -2314,6 +3457,19 @@ declare namespace ts {
         declaration?: SignatureDeclaration | JSDocSignature;
         typeParameters?: TypeParameter[];
         parameters: Symbol[];
+        thisParameter?: Symbol;
+        resolvedReturnType?: Type;
+        resolvedTypePredicate?: TypePredicate;
+        minArgumentCount: number;
+        hasRestParameter: boolean;
+        hasLiteralTypes: boolean;
+        target?: Signature;
+        mapper?: TypeMapper;
+        unionSignatures?: Signature[];
+        erasedSignatureCache?: Signature;
+        canonicalSignatureCache?: Signature;
+        isolatedSignatureType?: ObjectType;
+        instantiations?: Map<Signature>;
     }
     enum IndexKind {
         String = 0,
@@ -2324,6 +3480,7 @@ declare namespace ts {
         isReadonly: boolean;
         declaration?: IndexSignatureDeclaration;
     }
+    type TypeMapper = (t: TypeParameter) => Type;
     enum InferencePriority {
         NakedTypeVariable = 1,
         HomomorphicMappedType = 2,
@@ -2334,6 +3491,58 @@ declare namespace ts {
         AlwaysStrict = 64,
         PriorityImpliesCombination = 28
     }
+    interface InferenceInfo {
+        typeParameter: TypeParameter;
+        candidates: Type[] | undefined;
+        contraCandidates: Type[] | undefined;
+        inferredType?: Type;
+        priority?: InferencePriority;
+        topLevel: boolean;
+        isFixed: boolean;
+    }
+    enum InferenceFlags {
+        None = 0,
+        InferUnionTypes = 1,
+        NoDefault = 2,
+        AnyDefault = 4
+    }
+    /**
+     * Ternary values are defined such that
+     * x & y is False if either x or y is False.
+     * x & y is Maybe if either x or y is Maybe, but neither x or y is False.
+     * x & y is True if both x and y are True.
+     * x | y is False if both x and y are False.
+     * x | y is Maybe if either x or y is Maybe, but neither x or y is True.
+     * x | y is True if either x or y is True.
+     */
+    enum Ternary {
+        False = 0,
+        Maybe = 1,
+        True = -1
+    }
+    type TypeComparer = (s: Type, t: Type, reportErrors?: boolean) => Ternary;
+    interface InferenceContext extends TypeMapper {
+        typeParameters: TypeParameter[];
+        signature?: Signature;
+        inferences: InferenceInfo[];
+        flags: InferenceFlags;
+        compareTypes: TypeComparer;
+    }
+    interface WideningContext {
+        parent?: WideningContext;
+        propertyName?: __String;
+        siblings?: Type[];
+        resolvedProperties?: Symbol[];
+    }
+    enum SpecialPropertyAssignmentKind {
+        None = 0,
+        ExportsProperty = 1,
+        ModuleExports = 2,
+        PrototypeProperty = 3,
+        ThisProperty = 4,
+        Property = 5,
+        Prototype = 6
+    }
     /** @deprecated Use FileExtensionInfo instead. */
     type JsFileExtensionInfo = FileExtensionInfo;
     interface FileExtensionInfo {
@@ -2382,6 +3591,9 @@ declare namespace ts {
         Suggestion = 2,
         Message = 3
     }
+    function diagnosticCategoryName(d: {
+        category: DiagnosticCategory;
+    }, lowerCase?: boolean): string;
     enum ModuleResolutionKind {
         Classic = 1,
         NodeJs = 2
@@ -2401,31 +3613,44 @@ declare namespace ts {
     }
     type CompilerOptionsValue = string | number | boolean | (string | number)[] | string[] | MapLike<string[]> | PluginImport[] | ProjectReference[] | null | undefined;
     interface CompilerOptions {
+        all?: boolean;
         allowJs?: boolean;
+        allowNonTsExtensions?: boolean;
         allowSyntheticDefaultImports?: boolean;
         allowUnreachableCode?: boolean;
         allowUnusedLabels?: boolean;
         alwaysStrict?: boolean;
         baseUrl?: string;
+        /** An error if set - this should only go through the -b pipeline and not actually be observed */
+        build?: boolean;
         charset?: string;
         checkJs?: boolean;
+        configFilePath?: string;
+        /** configFile is set as non enumerable property so as to avoid checking of json source files */
+        readonly configFile?: TsConfigSourceFile;
         declaration?: boolean;
         declarationMap?: boolean;
         emitDeclarationOnly?: boolean;
         declarationDir?: string;
+        diagnostics?: boolean;
+        extendedDiagnostics?: boolean;
         disableSizeLimit?: boolean;
         downlevelIteration?: boolean;
         emitBOM?: boolean;
         emitDecoratorMetadata?: boolean;
         experimentalDecorators?: boolean;
         forceConsistentCasingInFileNames?: boolean;
+        help?: boolean;
         importHelpers?: boolean;
+        init?: boolean;
         inlineSourceMap?: boolean;
         inlineSources?: boolean;
         isolatedModules?: boolean;
         jsx?: JsxEmit;
         keyofStringsOnly?: boolean;
         lib?: string[];
+        listEmittedFiles?: boolean;
+        listFiles?: boolean;
         locale?: string;
         mapRoot?: string;
         maxNodeModuleJsDepth?: number;
@@ -2433,6 +3658,7 @@ declare namespace ts {
         moduleResolution?: ModuleResolutionKind;
         newLine?: NewLineKind;
         noEmit?: boolean;
+        noEmitForJsFiles?: boolean;
         noEmitHelpers?: boolean;
         noEmitOnError?: boolean;
         noErrorTruncation?: boolean;
@@ -2450,9 +3676,12 @@ declare namespace ts {
         outDir?: string;
         outFile?: string;
         paths?: MapLike<string[]>;
+        plugins?: PluginImport[];
         preserveConstEnums?: boolean;
         preserveSymlinks?: boolean;
+        preserveWatchOutput?: boolean;
         project?: string;
+        pretty?: boolean;
         reactNamespace?: string;
         jsxFactory?: string;
         composite?: boolean;
@@ -2467,14 +3696,18 @@ declare namespace ts {
         strictFunctionTypes?: boolean;
         strictNullChecks?: boolean;
         strictPropertyInitialization?: boolean;
+        stripInternal?: boolean;
         suppressExcessPropertyErrors?: boolean;
         suppressImplicitAnyIndexErrors?: boolean;
+        suppressOutputPathCheck?: boolean;
         target?: ScriptTarget;
         traceResolution?: boolean;
         resolveJsonModule?: boolean;
         types?: string[];
         /** Paths used to compute primary types search locations */
         typeRoots?: string[];
+        version?: boolean;
+        watch?: boolean;
         esModuleInterop?: boolean;
         [option: string]: CompilerOptionsValue | TsConfigSourceFile | undefined;
     }
@@ -2548,15 +3781,32 @@ declare namespace ts {
         errors: Diagnostic[];
         wildcardDirectories?: MapLike<WatchDirectoryFlags>;
         compileOnSave?: boolean;
+        configFileSpecs?: ConfigFileSpecs;
     }
     enum WatchDirectoryFlags {
         None = 0,
         Recursive = 1
     }
+    interface ConfigFileSpecs {
+        filesSpecs: ReadonlyArray<string> | undefined;
+        referencesSpecs: ReadonlyArray<ProjectReference> | undefined;
+        /**
+         * Present to report errors (user specified specs), validatedIncludeSpecs are used for file name matching
+         */
+        includeSpecs?: ReadonlyArray<string>;
+        /**
+         * Present to report errors (user specified specs), validatedExcludeSpecs are used for file name matching
+         */
+        excludeSpecs?: ReadonlyArray<string>;
+        validatedIncludeSpecs?: ReadonlyArray<string>;
+        validatedExcludeSpecs?: ReadonlyArray<string>;
+        wildcardDirectories: MapLike<WatchDirectoryFlags>;
+    }
     interface ExpandResult {
         fileNames: string[];
         projectReferences: ReadonlyArray<ProjectReference> | undefined;
         wildcardDirectories: MapLike<WatchDirectoryFlags>;
+        spec: ConfigFileSpecs;
     }
     interface CreateProgramOptions {
         rootNames: ReadonlyArray<string>;
@@ -2566,6 +3816,160 @@ declare namespace ts {
         oldProgram?: Program;
         configFileParsingDiagnostics?: ReadonlyArray<Diagnostic>;
     }
+    interface CommandLineOptionBase {
+        name: string;
+        type: "string" | "number" | "boolean" | "object" | "list" | Map<number | string>;
+        isFilePath?: boolean;
+        shortName?: string;
+        description?: DiagnosticMessage;
+        paramType?: DiagnosticMessage;
+        isTSConfigOnly?: boolean;
+        isCommandLineOnly?: boolean;
+        showInSimplifiedHelpView?: boolean;
+        category?: DiagnosticMessage;
+    }
+    interface CommandLineOptionOfPrimitiveType extends CommandLineOptionBase {
+        type: "string" | "number" | "boolean";
+    }
+    interface CommandLineOptionOfCustomType extends CommandLineOptionBase {
+        type: Map<number | string>;
+    }
+    interface TsConfigOnlyOption extends CommandLineOptionBase {
+        type: "object";
+        elementOptions?: Map<CommandLineOption>;
+        extraKeyDiagnosticMessage?: DiagnosticMessage;
+    }
+    interface CommandLineOptionOfListType extends CommandLineOptionBase {
+        type: "list";
+        element: CommandLineOptionOfCustomType | CommandLineOptionOfPrimitiveType | TsConfigOnlyOption;
+    }
+    type CommandLineOption = CommandLineOptionOfCustomType | CommandLineOptionOfPrimitiveType | TsConfigOnlyOption | CommandLineOptionOfListType;
+    enum CharacterCodes {
+        nullCharacter = 0,
+        maxAsciiCharacter = 127,
+        lineFeed = 10,
+        carriageReturn = 13,
+        lineSeparator = 8232,
+        paragraphSeparator = 8233,
+        nextLine = 133,
+        space = 32,
+        nonBreakingSpace = 160,
+        enQuad = 8192,
+        emQuad = 8193,
+        enSpace = 8194,
+        emSpace = 8195,
+        threePerEmSpace = 8196,
+        fourPerEmSpace = 8197,
+        sixPerEmSpace = 8198,
+        figureSpace = 8199,
+        punctuationSpace = 8200,
+        thinSpace = 8201,
+        hairSpace = 8202,
+        zeroWidthSpace = 8203,
+        narrowNoBreakSpace = 8239,
+        ideographicSpace = 12288,
+        mathematicalSpace = 8287,
+        ogham = 5760,
+        _ = 95,
+        $ = 36,
+        _0 = 48,
+        _1 = 49,
+        _2 = 50,
+        _3 = 51,
+        _4 = 52,
+        _5 = 53,
+        _6 = 54,
+        _7 = 55,
+        _8 = 56,
+        _9 = 57,
+        a = 97,
+        b = 98,
+        c = 99,
+        d = 100,
+        e = 101,
+        f = 102,
+        g = 103,
+        h = 104,
+        i = 105,
+        j = 106,
+        k = 107,
+        l = 108,
+        m = 109,
+        n = 110,
+        o = 111,
+        p = 112,
+        q = 113,
+        r = 114,
+        s = 115,
+        t = 116,
+        u = 117,
+        v = 118,
+        w = 119,
+        x = 120,
+        y = 121,
+        z = 122,
+        A = 65,
+        B = 66,
+        C = 67,
+        D = 68,
+        E = 69,
+        F = 70,
+        G = 71,
+        H = 72,
+        I = 73,
+        J = 74,
+        K = 75,
+        L = 76,
+        M = 77,
+        N = 78,
+        O = 79,
+        P = 80,
+        Q = 81,
+        R = 82,
+        S = 83,
+        T = 84,
+        U = 85,
+        V = 86,
+        W = 87,
+        X = 88,
+        Y = 89,
+        Z = 90,
+        ampersand = 38,
+        asterisk = 42,
+        at = 64,
+        backslash = 92,
+        backtick = 96,
+        bar = 124,
+        caret = 94,
+        closeBrace = 125,
+        closeBracket = 93,
+        closeParen = 41,
+        colon = 58,
+        comma = 44,
+        dot = 46,
+        doubleQuote = 34,
+        equals = 61,
+        exclamation = 33,
+        greaterThan = 62,
+        hash = 35,
+        lessThan = 60,
+        minus = 45,
+        openBrace = 123,
+        openBracket = 91,
+        openParen = 40,
+        percent = 37,
+        plus = 43,
+        question = 63,
+        semicolon = 59,
+        singleQuote = 39,
+        slash = 47,
+        tilde = 126,
+        backspace = 8,
+        formFeed = 12,
+        byteOrderMark = 65279,
+        tab = 9,
+        verticalTab = 11
+    }
     interface ModuleResolutionHost {
         fileExists(fileName: string): boolean;
         readFile(fileName: string): string | undefined;
@@ -2598,6 +4002,7 @@ declare namespace ts {
      * If changing this, remember to change `moduleResolutionIsEqualTo`.
      */
     interface ResolvedModuleFull extends ResolvedModule {
+        readonly originalPath?: string;
         /**
          * Extension of resolvedFileName. This must match what's at the end of resolvedFileName.
          * This is optional for backwards-compatibility, but will be added if not provided.
@@ -2634,6 +4039,7 @@ declare namespace ts {
     }
     interface ResolvedModuleWithFailedLookupLocations {
         readonly resolvedModule: ResolvedModuleFull | undefined;
+        readonly failedLookupLocations: ReadonlyArray<string>;
     }
     interface ResolvedTypeReferenceDirective {
         primary: boolean;
@@ -2644,6 +4050,7 @@ declare namespace ts {
         readonly resolvedTypeReferenceDirective: ResolvedTypeReferenceDirective | undefined;
         readonly failedLookupLocations: ReadonlyArray<string>;
     }
+    type HasInvalidatedResolution = (sourceFile: Path) => boolean;
     interface CompilerHost extends ModuleResolutionHost {
         getSourceFile(fileName: string, languageVersion: ScriptTarget, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined;
         getSourceFileByPath?(fileName: string, path: Path, languageVersion: ScriptTarget, onError?: (message: string) => void, shouldCreateNewSourceFile?: boolean): SourceFile | undefined;
@@ -2663,19 +4070,97 @@ declare namespace ts {
          */
         resolveTypeReferenceDirectives?(typeReferenceDirectiveNames: string[], containingFile: string): ResolvedTypeReferenceDirective[];
         getEnvironmentVariable?(name: string): string | undefined;
+        onReleaseOldSourceFile?(oldSourceFile: SourceFile, oldOptions: CompilerOptions): void;
+        hasInvalidatedResolution?: HasInvalidatedResolution;
+        hasChangedAutomaticTypeDirectiveNames?: boolean;
         createHash?(data: string): string;
         getModifiedTime?(fileName: string): Date;
         setModifiedTime?(fileName: string, date: Date): void;
         deleteFile?(fileName: string): void;
     }
+    enum TransformFlags {
+        None = 0,
+        TypeScript = 1,
+        ContainsTypeScript = 2,
+        ContainsJsx = 4,
+        ContainsESNext = 8,
+        ContainsES2017 = 16,
+        ContainsES2016 = 32,
+        ES2015 = 64,
+        ContainsES2015 = 128,
+        Generator = 256,
+        ContainsGenerator = 512,
+        DestructuringAssignment = 1024,
+        ContainsDestructuringAssignment = 2048,
+        ContainsDecorators = 4096,
+        ContainsPropertyInitializer = 8192,
+        ContainsLexicalThis = 16384,
+        ContainsCapturedLexicalThis = 32768,
+        ContainsLexicalThisInComputedPropertyName = 65536,
+        ContainsDefaultValueAssignments = 131072,
+        ContainsParameterPropertyAssignments = 262144,
+        ContainsSpread = 524288,
+        ContainsObjectSpread = 1048576,
+        ContainsRest = 524288,
+        ContainsObjectRest = 1048576,
+        ContainsComputedPropertyName = 2097152,
+        ContainsBlockScopedBinding = 4194304,
+        ContainsBindingPattern = 8388608,
+        ContainsYield = 16777216,
+        ContainsHoistedDeclarationOrCompletion = 33554432,
+        ContainsDynamicImport = 67108864,
+        Super = 134217728,
+        ContainsSuper = 268435456,
+        HasComputedFlags = 536870912,
+        AssertTypeScript = 3,
+        AssertJsx = 4,
+        AssertESNext = 8,
+        AssertES2017 = 16,
+        AssertES2016 = 32,
+        AssertES2015 = 192,
+        AssertGenerator = 768,
+        AssertDestructuringAssignment = 3072,
+        OuterExpressionExcludes = 536872257,
+        PropertyAccessExcludes = 671089985,
+        NodeExcludes = 939525441,
+        ArrowFunctionExcludes = 1003902273,
+        FunctionExcludes = 1003935041,
+        ConstructorExcludes = 1003668801,
+        MethodOrAccessorExcludes = 1003668801,
+        ClassExcludes = 942011713,
+        ModuleExcludes = 977327425,
+        TypeExcludes = -3,
+        ObjectLiteralExcludes = 942740801,
+        ArrayLiteralOrCallOrNewExcludes = 940049729,
+        VariableDeclarationListExcludes = 948962625,
+        ParameterExcludes = 939525441,
+        CatchClauseExcludes = 940574017,
+        BindingPatternExcludes = 940049729,
+        TypeScriptClassSyntaxMask = 274432,
+        ES2015FunctionSyntaxMask = 163840
+    }
     interface SourceMapRange extends TextRange {
         source?: SourceMapSource;
     }
     interface SourceMapSource {
         fileName: string;
         text: string;
+        lineMap: ReadonlyArray<number>;
         skipTrivia?: (pos: number) => number;
     }
+    interface EmitNode {
+        annotatedNodes?: Node[];
+        flags: EmitFlags;
+        leadingComments?: SynthesizedComment[];
+        trailingComments?: SynthesizedComment[];
+        commentRange?: TextRange;
+        sourceMapRange?: SourceMapRange;
+        tokenSourceMapRanges?: (SourceMapRange | undefined)[];
+        constantValue?: string | number;
+        externalHelpersModuleName?: Identifier;
+        helpers?: EmitHelper[];
+        startsOnNewLine?: boolean;
+    }
     enum EmitFlags {
         None = 0,
         SingleLine = 1,
@@ -2705,7 +4190,9 @@ declare namespace ts {
         NoHoisting = 2097152,
         HasEndOfDeclarationMarker = 4194304,
         Iterator = 8388608,
-        NoAsciiEscaping = 16777216
+        NoAsciiEscaping = 16777216,
+        TypeScriptClassWrapper = 33554432,
+        NeverApplyImportHelper = 67108864
     }
     interface EmitHelper {
         readonly name: string;
@@ -2713,7 +4200,38 @@ declare namespace ts {
         readonly text: string | ((node: EmitHelperUniqueNameCallback) => string);
         readonly priority?: number;
     }
+    type UniqueNameHandler = (baseName: string, checkFn?: (name: string) => boolean, optimistic?: boolean) => string;
     type EmitHelperUniqueNameCallback = (name: string) => string;
+    /**
+     * Used by the checker, this enum keeps track of external emit helpers that should be type
+     * checked.
+     */
+    enum ExternalEmitHelpers {
+        Extends = 1,
+        Assign = 2,
+        Rest = 4,
+        Decorate = 8,
+        Metadata = 16,
+        Param = 32,
+        Awaiter = 64,
+        Generator = 128,
+        Values = 256,
+        Read = 512,
+        Spread = 1024,
+        Await = 2048,
+        AsyncGenerator = 4096,
+        AsyncDelegator = 8192,
+        AsyncValues = 16384,
+        ExportStar = 32768,
+        MakeTemplateObject = 65536,
+        FirstEmitHelper = 1,
+        LastEmitHelper = 65536,
+        ForOfIncludes = 256,
+        ForAwaitOfIncludes = 16384,
+        AsyncGeneratorIncludes = 6144,
+        AsyncDelegatorIncludes = 26624,
+        SpreadIncludes = 1536
+    }
     enum EmitHint {
         SourceFile = 0,
         Expression = 1,
@@ -2721,7 +4239,20 @@ declare namespace ts {
         MappedTypeParameter = 3,
         Unspecified = 4
     }
+    interface EmitHost extends ScriptReferenceHost, ModuleSpecifierResolutionHost {
+        getSourceFiles(): ReadonlyArray<SourceFile>;
+        getCurrentDirectory(): string;
+        isSourceFileFromExternalLibrary(file: SourceFile): boolean;
+        getCommonSourceDirectory(): string;
+        getCanonicalFileName(fileName: string): string;
+        getNewLine(): string;
+        isEmitBlocked(emitFileName: string): boolean;
+        getPrependNodes(): ReadonlyArray<InputFiles>;
+        writeFile: WriteFileCallback;
+    }
     interface TransformationContext {
+        getEmitResolver(): EmitResolver;
+        getEmitHost(): EmitHost;
         /** Gets the compiler options supplied to the transformer. */
         getCompilerOptions(): CompilerOptions;
         /** Starts a new lexical environment. */
@@ -2770,6 +4301,7 @@ declare namespace ts {
          * before returning the `NodeTransformer` callback.
          */
         onEmitNode: (hint: EmitHint, node: Node, emitCallback: (hint: EmitHint, node: Node) => void) => void;
+        addDiagnostic(diag: DiagnosticWithLocation): void;
     }
     interface TransformationResult<T extends Node> {
         /** Gets the transformed source files. */
@@ -2837,6 +4369,20 @@ declare namespace ts {
          * Prints a bundle of source files as-is, without any emit transformations.
          */
         printBundle(bundle: Bundle): string;
+        writeNode(hint: EmitHint, node: Node, sourceFile: SourceFile | undefined, writer: EmitTextWriter): void;
+        writeList<T extends Node>(format: ListFormat, list: NodeArray<T> | undefined, sourceFile: SourceFile | undefined, writer: EmitTextWriter): void;
+        writeFile(sourceFile: SourceFile, writer: EmitTextWriter): void;
+        writeBundle(bundle: Bundle, writer: EmitTextWriter, info?: BundleInfo): void;
+    }
+    /**
+     * When a bundle contains prepended content, we store a file on disk indicating where the non-prepended
+     * content of that file starts. On a subsequent build where there are no upstream .d.ts changes, we
+     * read the bundle info file and the original .js file to quickly re-use portion of the file
+     * that didn't originate in prepended content.
+     */
+    interface BundleInfo {
+        originalOffset: number;
+        totalLength: number;
     }
     interface PrintHandlers {
         /**
@@ -2880,23 +4426,57 @@ declare namespace ts {
          * ```
          */
         substituteNode?(hint: EmitHint, node: Node): Node;
+        onEmitSourceMapOfNode?: (hint: EmitHint, node: Node, emitCallback: (hint: EmitHint, node: Node) => void) => void;
+        onEmitSourceMapOfToken?: (node: Node | undefined, token: SyntaxKind, writer: (s: string) => void, pos: number, emitCallback: (token: SyntaxKind, writer: (s: string) => void, pos: number) => number) => number;
+        onEmitSourceMapOfPosition?: (pos: number) => void;
+        onSetSourceFile?: (node: SourceFile) => void;
+        onBeforeEmitNodeArray?: (nodes: NodeArray<any> | undefined) => void;
+        onAfterEmitNodeArray?: (nodes: NodeArray<any> | undefined) => void;
+        onBeforeEmitToken?: (node: Node) => void;
+        onAfterEmitToken?: (node: Node) => void;
     }
     interface PrinterOptions {
         removeComments?: boolean;
         newLine?: NewLineKind;
         omitTrailingSemicolon?: boolean;
         noEmitHelpers?: boolean;
+        module?: CompilerOptions["module"];
+        target?: CompilerOptions["target"];
+        sourceMap?: boolean;
+        inlineSourceMap?: boolean;
+        extendedDiagnostics?: boolean;
+        onlyPrintJsDocStyle?: boolean;
+    }
+    interface EmitTextWriter extends SymbolWriter {
+        write(s: string): void;
+        writeTextOfNode(text: string, node: Node): void;
+        getText(): string;
+        rawWrite(s: string): void;
+        writeLiteral(s: string): void;
+        getTextPos(): number;
+        getLine(): number;
+        getColumn(): number;
+        getIndent(): number;
+        isAtStartOfLine(): boolean;
     }
     interface GetEffectiveTypeRootsHost {
         directoryExists?(directoryName: string): boolean;
         getCurrentDirectory?(): string;
     }
+    /** @internal */
+    interface ModuleSpecifierResolutionHost extends GetEffectiveTypeRootsHost {
+        useCaseSensitiveFileNames?(): boolean;
+        fileExists?(path: string): boolean;
+        readFile?(path: string): string | undefined;
+    }
     /** @deprecated See comment on SymbolWriter */
     interface SymbolTracker {
         trackSymbol?(symbol: Symbol, enclosingDeclaration?: Node, meaning?: SymbolFlags): void;
         reportInaccessibleThisError?(): void;
         reportPrivateInBaseOfClassExpression?(propertyName: string): void;
         reportInaccessibleUniqueSymbolError?(): void;
+        moduleResolverHost?: ModuleSpecifierResolutionHost;
+        trackReferencedAmbientModule?(decl: ModuleDeclaration): void;
     }
     interface TextSpan {
         start: number;
@@ -2906,8 +4486,12 @@ declare namespace ts {
         span: TextSpan;
         newLength: number;
     }
-    interface SortedArray<T> extends Array<T> {
-        " __sortedArrayBrand": any;
+    interface DiagnosticCollection {
+        add(diagnostic: Diagnostic): void;
+        getGlobalDiagnostics(): Diagnostic[];
+        getDiagnostics(fileName: string): DiagnosticWithLocation[];
+        getDiagnostics(): Diagnostic[];
+        reattachFileDiagnostics(newFile: SourceFile): void;
     }
     interface SyntaxList extends Node {
         _children: Node[];
@@ -2977,19 +4561,145 @@ declare namespace ts {
         Parameters = 1296,
         IndexSignatureParameters = 4432
     }
-}
-declare namespace ts {
-    const versionMajorMinor = "3.0";
-    /** The version of the TypeScript compiler release */
-    const version: string;
-}
-declare namespace ts {
-    function isExternalModuleNameRelative(moduleName: string): boolean;
-    function sortAndDeduplicateDiagnostics<T extends Diagnostic>(diagnostics: ReadonlyArray<T>): T[];
+    enum PragmaKindFlags {
+        None = 0,
+        /**
+         * Triple slash comment of the form
+         * /// <pragma-name argname="value" />
+         */
+        TripleSlashXML = 1,
+        /**
+         * Single line comment of the form
+         * // @pragma-name argval1 argval2
+         * or
+         * /// @pragma-name argval1 argval2
+         */
+        SingleLine = 2,
+        /**
+         * Multiline non-jsdoc pragma of the form
+         * /* @pragma-name argval1 argval2 * /
+         */
+        MultiLine = 4,
+        All = 7,
+        Default = 7
+    }
+    interface PragmaArgumentSpecification<TName extends string> {
+        name: TName;
+        optional?: boolean;
+        captureSpan?: boolean;
+    }
+    interface PragmaDefinition<T1 extends string = string, T2 extends string = string, T3 extends string = string, T4 extends string = string> {
+        args?: [PragmaArgumentSpecification<T1>] | [PragmaArgumentSpecification<T1>, PragmaArgumentSpecification<T2>] | [PragmaArgumentSpecification<T1>, PragmaArgumentSpecification<T2>, PragmaArgumentSpecification<T3>] | [PragmaArgumentSpecification<T1>, PragmaArgumentSpecification<T2>, PragmaArgumentSpecification<T3>, PragmaArgumentSpecification<T4>];
+        kind?: PragmaKindFlags;
+    }
+    const commentPragmas: {
+        "reference": {
+            args: [{
+                name: "types";
+                optional: true;
+                captureSpan: true;
+            }, {
+                name: "lib";
+                optional: true;
+                captureSpan: true;
+            }, {
+                name: "path";
+                optional: true;
+                captureSpan: true;
+            }, {
+                name: "no-default-lib";
+                optional: true;
+            }];
+            kind: PragmaKindFlags;
+        };
+        "amd-dependency": {
+            args: [{
+                name: "path";
+            }, {
+                name: "name";
+                optional: true;
+            }];
+            kind: PragmaKindFlags;
+        };
+        "amd-module": {
+            args: [{
+                name: "name";
+            }];
+            kind: PragmaKindFlags;
+        };
+        "ts-check": {
+            kind: PragmaKindFlags;
+        };
+        "ts-nocheck": {
+            kind: PragmaKindFlags;
+        };
+        "jsx": {
+            args: [{
+                name: "factory";
+            }];
+            kind: PragmaKindFlags;
+        };
+    };
+    type PragmaArgTypeMaybeCapture<TDesc> = TDesc extends {
+        captureSpan: true;
+    } ? {
+        value: string;
+        pos: number;
+        end: number;
+    } : string;
+    type PragmaArgTypeOptional<TDesc, TName extends string> = TDesc extends {
+        optional: true;
+    } ? {
+        [K in TName]?: PragmaArgTypeMaybeCapture<TDesc>;
+    } : {
+        [K in TName]: PragmaArgTypeMaybeCapture<TDesc>;
+    };
+    /**
+     * Maps a pragma definition into the desired shape for its arguments object
+     * Maybe the below is a good argument for types being iterable on struture in some way.
+     */
+    type PragmaArgumentType<T extends PragmaDefinition> = T extends {
+        args: [PragmaArgumentSpecification<infer TName1>, PragmaArgumentSpecification<infer TName2>, PragmaArgumentSpecification<infer TName3>, PragmaArgumentSpecification<infer TName4>];
+    } ? PragmaArgTypeOptional<T["args"][0], TName1> & PragmaArgTypeOptional<T["args"][1], TName2> & PragmaArgTypeOptional<T["args"][2], TName3> & PragmaArgTypeOptional<T["args"][2], TName4> : T extends {
+        args: [PragmaArgumentSpecification<infer TName1>, PragmaArgumentSpecification<infer TName2>, PragmaArgumentSpecification<infer TName3>];
+    } ? PragmaArgTypeOptional<T["args"][0], TName1> & PragmaArgTypeOptional<T["args"][1], TName2> & PragmaArgTypeOptional<T["args"][2], TName3> : T extends {
+        args: [PragmaArgumentSpecification<infer TName1>, PragmaArgumentSpecification<infer TName2>];
+    } ? PragmaArgTypeOptional<T["args"][0], TName1> & PragmaArgTypeOptional<T["args"][1], TName2> : T extends {
+        args: [PragmaArgumentSpecification<infer TName>];
+    } ? PragmaArgTypeOptional<T["args"][0], TName> : object;
+    type ConcretePragmaSpecs = typeof commentPragmas;
+    type PragmaPsuedoMap = {
+        [K in keyof ConcretePragmaSpecs]?: {
+            arguments: PragmaArgumentType<ConcretePragmaSpecs[K]>;
+            range: CommentRange;
+        };
+    };
+    type PragmaPsuedoMapEntry = {
+        [K in keyof PragmaPsuedoMap]: {
+            name: K;
+            args: PragmaPsuedoMap[K];
+        };
+    }[keyof PragmaPsuedoMap];
+    /**
+     * A strongly-typed es6 map of pragma entries, the values of which are either a single argument
+     * value (if only one was found), or an array of multiple argument values if the pragma is present
+     * in multiple places
+     */
+    interface PragmaMap extends Map<PragmaPsuedoMap[keyof PragmaPsuedoMap] | PragmaPsuedoMap[keyof PragmaPsuedoMap][]> {
+        set<TKey extends keyof PragmaPsuedoMap>(key: TKey, value: PragmaPsuedoMap[TKey] | PragmaPsuedoMap[TKey][]): this;
+        get<TKey extends keyof PragmaPsuedoMap>(key: TKey): PragmaPsuedoMap[TKey] | PragmaPsuedoMap[TKey][];
+        forEach(action: <TKey extends keyof PragmaPsuedoMap>(value: PragmaPsuedoMap[TKey] | PragmaPsuedoMap[TKey][], key: TKey) => void): void;
+    }
 }
 declare function setTimeout(handler: (...args: any[]) => void, timeout: number): any;
 declare function clearTimeout(handle: any): void;
 declare namespace ts {
+    /**
+     * Set a high stack trace limit to provide more information in case of an error.
+     * Called for command-line and server use cases.
+     * Not called if TypeScript is used as a library.
+     */
+    function setStackTraceLimit(): void;
     enum FileWatcherEventKind {
         Created = 0,
         Changed = 1,
@@ -2997,6 +4707,47 @@ declare namespace ts {
     }
     type FileWatcherCallback = (fileName: string, eventKind: FileWatcherEventKind) => void;
     type DirectoryWatcherCallback = (fileName: string) => void;
+    interface WatchedFile {
+        readonly fileName: string;
+        readonly callback: FileWatcherCallback;
+        mtime: Date;
+    }
+    enum PollingInterval {
+        High = 2000,
+        Medium = 500,
+        Low = 250
+    }
+    function watchFileUsingPriorityPollingInterval(host: System, fileName: string, callback: FileWatcherCallback, watchPriority: PollingInterval): FileWatcher;
+    type HostWatchFile = (fileName: string, callback: FileWatcherCallback, pollingInterval: PollingInterval | undefined) => FileWatcher;
+    type HostWatchDirectory = (fileName: string, callback: DirectoryWatcherCallback, recursive?: boolean) => FileWatcher;
+    const missingFileModifiedTime: Date;
+    let unchangedPollThresholds: {
+        [PollingInterval.Low]: number;
+        [PollingInterval.Medium]: number;
+        [PollingInterval.High]: number;
+    };
+    function setCustomPollingValues(system: System): void;
+    function createDynamicPriorityPollingWatchFile(host: {
+        getModifiedTime: System["getModifiedTime"];
+        setTimeout: System["setTimeout"];
+    }): HostWatchFile;
+    /**
+     * Returns true if file status changed
+     */
+    function onWatchedFileStat(watchedFile: WatchedFile, modifiedTime: Date): boolean;
+    interface RecursiveDirectoryWatcherHost {
+        watchDirectory: HostWatchDirectory;
+        getAccessibleSortedChildDirectories(path: string): ReadonlyArray<string>;
+        directoryExists(dir: string): boolean;
+        filePathComparer: Comparer<string>;
+        realpath(s: string): string;
+    }
+    /**
+     * Watch the directory recursively using host provided method to watch child directories
+     * that means if this is recursive watcher, watch the children directories as well
+     * (eg on OS that dont support recursive watch using fs.watch use fs.watchFile)
+     */
+    function createRecursiveDirectoryWatcher(host: RecursiveDirectoryWatcherHost): (directoryName: string, callback: DirectoryWatcherCallback) => FileWatcher;
     interface System {
         args: string[];
         newLine: string;
@@ -3032,9 +4783,13 @@ declare namespace ts {
         getMemoryUsage?(): number;
         exit(exitCode?: number): void;
         realpath?(path: string): string;
+        getEnvironmentVariable(name: string): string;
+        tryEnableSourceMapsForHost?(): void;
+        debugMode?: boolean;
         setTimeout?(callback: (...args: any[]) => void, ms: number, ...args: any[]): any;
         clearTimeout?(timeoutId: any): void;
         clearScreen?(): void;
+        setBlocking?(): void;
         base64decode?(input: string): string;
         base64encode?(input: string): string;
     }
@@ -3044,8 +4799,1113 @@ declare namespace ts {
     function getNodeMajorVersion(): number | undefined;
     let sys: System;
 }
+declare namespace ts {
+    const Diagnostics: {
+        Unterminated_string_literal: DiagnosticMessage;
+        Identifier_expected: DiagnosticMessage;
+        _0_expected: DiagnosticMessage;
+        A_file_cannot_have_a_reference_to_itself: DiagnosticMessage;
+        Trailing_comma_not_allowed: DiagnosticMessage;
+        Asterisk_Slash_expected: DiagnosticMessage;
+        An_element_access_expression_should_take_an_argument: DiagnosticMessage;
+        Unexpected_token: DiagnosticMessage;
+        A_rest_parameter_or_binding_pattern_may_not_have_a_trailing_comma: DiagnosticMessage;
+        A_rest_parameter_must_be_last_in_a_parameter_list: DiagnosticMessage;
+        Parameter_cannot_have_question_mark_and_initializer: DiagnosticMessage;
+        A_required_parameter_cannot_follow_an_optional_parameter: DiagnosticMessage;
+        An_index_signature_cannot_have_a_rest_parameter: DiagnosticMessage;
+        An_index_signature_parameter_cannot_have_an_accessibility_modifier: DiagnosticMessage;
+        An_index_signature_parameter_cannot_have_a_question_mark: DiagnosticMessage;
+        An_index_signature_parameter_cannot_have_an_initializer: DiagnosticMessage;
+        An_index_signature_must_have_a_type_annotation: DiagnosticMessage;
+        An_index_signature_parameter_must_have_a_type_annotation: DiagnosticMessage;
+        An_index_signature_parameter_type_must_be_string_or_number: DiagnosticMessage;
+        readonly_modifier_can_only_appear_on_a_property_declaration_or_index_signature: DiagnosticMessage;
+        Accessibility_modifier_already_seen: DiagnosticMessage;
+        _0_modifier_must_precede_1_modifier: DiagnosticMessage;
+        _0_modifier_already_seen: DiagnosticMessage;
+        _0_modifier_cannot_appear_on_a_class_element: DiagnosticMessage;
+        super_must_be_followed_by_an_argument_list_or_member_access: DiagnosticMessage;
+        Only_ambient_modules_can_use_quoted_names: DiagnosticMessage;
+        Statements_are_not_allowed_in_ambient_contexts: DiagnosticMessage;
+        A_declare_modifier_cannot_be_used_in_an_already_ambient_context: DiagnosticMessage;
+        Initializers_are_not_allowed_in_ambient_contexts: DiagnosticMessage;
+        _0_modifier_cannot_be_used_in_an_ambient_context: DiagnosticMessage;
+        _0_modifier_cannot_be_used_with_a_class_declaration: DiagnosticMessage;
+        _0_modifier_cannot_be_used_here: DiagnosticMessage;
+        _0_modifier_cannot_appear_on_a_data_property: DiagnosticMessage;
+        _0_modifier_cannot_appear_on_a_module_or_namespace_element: DiagnosticMessage;
+        A_0_modifier_cannot_be_used_with_an_interface_declaration: DiagnosticMessage;
+        A_declare_modifier_is_required_for_a_top_level_declaration_in_a_d_ts_file: DiagnosticMessage;
+        A_rest_parameter_cannot_be_optional: DiagnosticMessage;
+        A_rest_parameter_cannot_have_an_initializer: DiagnosticMessage;
+        A_set_accessor_must_have_exactly_one_parameter: DiagnosticMessage;
+        A_set_accessor_cannot_have_an_optional_parameter: DiagnosticMessage;
+        A_set_accessor_parameter_cannot_have_an_initializer: DiagnosticMessage;
+        A_set_accessor_cannot_have_rest_parameter: DiagnosticMessage;
+        A_get_accessor_cannot_have_parameters: DiagnosticMessage;
+        Type_0_is_not_a_valid_async_function_return_type_in_ES5_SlashES3_because_it_does_not_refer_to_a_Promise_compatible_constructor_value: DiagnosticMessage;
+        Accessors_are_only_available_when_targeting_ECMAScript_5_and_higher: DiagnosticMessage;
+        An_async_function_or_method_must_have_a_valid_awaitable_return_type: DiagnosticMessage;
+        The_return_type_of_an_async_function_must_either_be_a_valid_promise_or_must_not_contain_a_callable_then_member: DiagnosticMessage;
+        A_promise_must_have_a_then_method: DiagnosticMessage;
+        The_first_parameter_of_the_then_method_of_a_promise_must_be_a_callback: DiagnosticMessage;
+        Enum_member_must_have_initializer: DiagnosticMessage;
+        Type_is_referenced_directly_or_indirectly_in_the_fulfillment_callback_of_its_own_then_method: DiagnosticMessage;
+        An_export_assignment_cannot_be_used_in_a_namespace: DiagnosticMessage;
+        The_return_type_of_an_async_function_or_method_must_be_the_global_Promise_T_type: DiagnosticMessage;
+        In_ambient_enum_declarations_member_initializer_must_be_constant_expression: DiagnosticMessage;
+        Unexpected_token_A_constructor_method_accessor_or_property_was_expected: DiagnosticMessage;
+        Unexpected_token_A_type_parameter_name_was_expected_without_curly_braces: DiagnosticMessage;
+        _0_modifier_cannot_appear_on_a_type_member: DiagnosticMessage;
+        _0_modifier_cannot_appear_on_an_index_signature: DiagnosticMessage;
+        A_0_modifier_cannot_be_used_with_an_import_declaration: DiagnosticMessage;
+        Invalid_reference_directive_syntax: DiagnosticMessage;
+        Octal_literals_are_not_available_when_targeting_ECMAScript_5_and_higher_Use_the_syntax_0: DiagnosticMessage;
+        An_accessor_cannot_be_declared_in_an_ambient_context: DiagnosticMessage;
+        _0_modifier_cannot_appear_on_a_constructor_declaration: DiagnosticMessage;
+        _0_modifier_cannot_appear_on_a_parameter: DiagnosticMessage;
+        Only_a_single_variable_declaration_is_allowed_in_a_for_in_statement: DiagnosticMessage;
+        Type_parameters_cannot_appear_on_a_constructor_declaration: DiagnosticMessage;
+        Type_annotation_cannot_appear_on_a_constructor_declaration: DiagnosticMessage;
+        An_accessor_cannot_have_type_parameters: DiagnosticMessage;
+        A_set_accessor_cannot_have_a_return_type_annotation: DiagnosticMessage;
+        An_index_signature_must_have_exactly_one_parameter: DiagnosticMessage;
+        _0_list_cannot_be_empty: DiagnosticMessage;
+        Type_parameter_list_cannot_be_empty: DiagnosticMessage;
+        Type_argument_list_cannot_be_empty: DiagnosticMessage;
+        Invalid_use_of_0_in_strict_mode: DiagnosticMessage;
+        with_statements_are_not_allowed_in_strict_mode: DiagnosticMessage;
+        delete_cannot_be_called_on_an_identifier_in_strict_mode: DiagnosticMessage;
+        A_for_await_of_statement_is_only_allowed_within_an_async_function_or_async_generator: DiagnosticMessage;
+        A_continue_statement_can_only_be_used_within_an_enclosing_iteration_statement: DiagnosticMessage;
+        A_break_statement_can_only_be_used_within_an_enclosing_iteration_or_switch_statement: DiagnosticMessage;
+        Jump_target_cannot_cross_function_boundary: DiagnosticMessage;
+        A_return_statement_can_only_be_used_within_a_function_body: DiagnosticMessage;
+        Expression_expected: DiagnosticMessage;
+        Type_expected: DiagnosticMessage;
+        A_default_clause_cannot_appear_more_than_once_in_a_switch_statement: DiagnosticMessage;
+        Duplicate_label_0: DiagnosticMessage;
+        A_continue_statement_can_only_jump_to_a_label_of_an_enclosing_iteration_statement: DiagnosticMessage;
+        A_break_statement_can_only_jump_to_a_label_of_an_enclosing_statement: DiagnosticMessage;
+        An_object_literal_cannot_have_multiple_properties_with_the_same_name_in_strict_mode: DiagnosticMessage;
+        An_object_literal_cannot_have_multiple_get_Slashset_accessors_with_the_same_name: DiagnosticMessage;
+        An_object_literal_cannot_have_property_and_accessor_with_the_same_name: DiagnosticMessage;
+        An_export_assignment_cannot_have_modifiers: DiagnosticMessage;
+        Octal_literals_are_not_allowed_in_strict_mode: DiagnosticMessage;
+        A_tuple_type_element_list_cannot_be_empty: DiagnosticMessage;
+        Variable_declaration_list_cannot_be_empty: DiagnosticMessage;
+        Digit_expected: DiagnosticMessage;
+        Hexadecimal_digit_expected: DiagnosticMessage;
+        Unexpected_end_of_text: DiagnosticMessage;
+        Invalid_character: DiagnosticMessage;
+        Declaration_or_statement_expected: DiagnosticMessage;
+        Statement_expected: DiagnosticMessage;
+        case_or_default_expected: DiagnosticMessage;
+        Property_or_signature_expected: DiagnosticMessage;
+        Enum_member_expected: DiagnosticMessage;
+        Variable_declaration_expected: DiagnosticMessage;
+        Argument_expression_expected: DiagnosticMessage;
+        Property_assignment_expected: DiagnosticMessage;
+        Expression_or_comma_expected: DiagnosticMessage;
+        Parameter_declaration_expected: DiagnosticMessage;
+        Type_parameter_declaration_expected: DiagnosticMessage;
+        Type_argument_expected: DiagnosticMessage;
+        String_literal_expected: DiagnosticMessage;
+        Line_break_not_permitted_here: DiagnosticMessage;
+        or_expected: DiagnosticMessage;
+        Declaration_expected: DiagnosticMessage;
+        Import_declarations_in_a_namespace_cannot_reference_a_module: DiagnosticMessage;
+        Cannot_use_imports_exports_or_module_augmentations_when_module_is_none: DiagnosticMessage;
+        File_name_0_differs_from_already_included_file_name_1_only_in_casing: DiagnosticMessage;
+        new_T_cannot_be_used_to_create_an_array_Use_new_Array_T_instead: DiagnosticMessage;
+        const_declarations_must_be_initialized: DiagnosticMessage;
+        const_declarations_can_only_be_declared_inside_a_block: DiagnosticMessage;
+        let_declarations_can_only_be_declared_inside_a_block: DiagnosticMessage;
+        Unterminated_template_literal: DiagnosticMessage;
+        Unterminated_regular_expression_literal: DiagnosticMessage;
+        An_object_member_cannot_be_declared_optional: DiagnosticMessage;
+        A_yield_expression_is_only_allowed_in_a_generator_body: DiagnosticMessage;
+        Computed_property_names_are_not_allowed_in_enums: DiagnosticMessage;
+        A_computed_property_name_in_an_ambient_context_must_refer_to_an_expression_whose_type_is_a_literal_type_or_a_unique_symbol_type: DiagnosticMessage;
+        A_computed_property_name_in_a_class_property_declaration_must_refer_to_an_expression_whose_type_is_a_literal_type_or_a_unique_symbol_type: DiagnosticMessage;
+        A_computed_property_name_in_a_method_overload_must_refer_to_an_expression_whose_type_is_a_literal_type_or_a_unique_symbol_type: DiagnosticMessage;
+        A_computed_property_name_in_an_interface_must_refer_to_an_expression_whose_type_is_a_literal_type_or_a_unique_symbol_type: DiagnosticMessage;
+        A_computed_property_name_in_a_type_literal_must_refer_to_an_expression_whose_type_is_a_literal_type_or_a_unique_symbol_type: DiagnosticMessage;
+        A_comma_expression_is_not_allowed_in_a_computed_property_name: DiagnosticMessage;
+        extends_clause_already_seen: DiagnosticMessage;
+        extends_clause_must_precede_implements_clause: DiagnosticMessage;
+        Classes_can_only_extend_a_single_class: DiagnosticMessage;
+        implements_clause_already_seen: DiagnosticMessage;
+        Interface_declaration_cannot_have_implements_clause: DiagnosticMessage;
+        Binary_digit_expected: DiagnosticMessage;
+        Octal_digit_expected: DiagnosticMessage;
+        Unexpected_token_expected: DiagnosticMessage;
+        Property_destructuring_pattern_expected: DiagnosticMessage;
+        Array_element_destructuring_pattern_expected: DiagnosticMessage;
+        A_destructuring_declaration_must_have_an_initializer: DiagnosticMessage;
+        An_implementation_cannot_be_declared_in_ambient_contexts: DiagnosticMessage;
+        Modifiers_cannot_appear_here: DiagnosticMessage;
+        Merge_conflict_marker_encountered: DiagnosticMessage;
+        A_rest_element_cannot_have_an_initializer: DiagnosticMessage;
+        A_parameter_property_may_not_be_declared_using_a_binding_pattern: DiagnosticMessage;
+        Only_a_single_variable_declaration_is_allowed_in_a_for_of_statement: DiagnosticMessage;
+        The_variable_declaration_of_a_for_in_statement_cannot_have_an_initializer: DiagnosticMessage;
+        The_variable_declaration_of_a_for_of_statement_cannot_have_an_initializer: DiagnosticMessage;
+        An_import_declaration_cannot_have_modifiers: DiagnosticMessage;
+        Module_0_has_no_default_export: DiagnosticMessage;
+        An_export_declaration_cannot_have_modifiers: DiagnosticMessage;
+        Export_declarations_are_not_permitted_in_a_namespace: DiagnosticMessage;
+        Catch_clause_variable_cannot_have_a_type_annotation: DiagnosticMessage;
+        Catch_clause_variable_cannot_have_an_initializer: DiagnosticMessage;
+        An_extended_Unicode_escape_value_must_be_between_0x0_and_0x10FFFF_inclusive: DiagnosticMessage;
+        Unterminated_Unicode_escape_sequence: DiagnosticMessage;
+        Line_terminator_not_permitted_before_arrow: DiagnosticMessage;
+        Import_assignment_cannot_be_used_when_targeting_ECMAScript_modules_Consider_using_import_Asterisk_as_ns_from_mod_import_a_from_mod_import_d_from_mod_or_another_module_format_instead: DiagnosticMessage;
+        Export_assignment_cannot_be_used_when_targeting_ECMAScript_modules_Consider_using_export_default_or_another_module_format_instead: DiagnosticMessage;
+        Cannot_re_export_a_type_when_the_isolatedModules_flag_is_provided: DiagnosticMessage;
+        Decorators_are_not_valid_here: DiagnosticMessage;
+        Decorators_cannot_be_applied_to_multiple_get_Slashset_accessors_of_the_same_name: DiagnosticMessage;
+        Cannot_compile_namespaces_when_the_isolatedModules_flag_is_provided: DiagnosticMessage;
+        Ambient_const_enums_are_not_allowed_when_the_isolatedModules_flag_is_provided: DiagnosticMessage;
+        Invalid_use_of_0_Class_definitions_are_automatically_in_strict_mode: DiagnosticMessage;
+        A_class_declaration_without_the_default_modifier_must_have_a_name: DiagnosticMessage;
+        Identifier_expected_0_is_a_reserved_word_in_strict_mode: DiagnosticMessage;
+        Identifier_expected_0_is_a_reserved_word_in_strict_mode_Class_definitions_are_automatically_in_strict_mode: DiagnosticMessage;
+        Identifier_expected_0_is_a_reserved_word_in_strict_mode_Modules_are_automatically_in_strict_mode: DiagnosticMessage;
+        Invalid_use_of_0_Modules_are_automatically_in_strict_mode: DiagnosticMessage;
+        Identifier_expected_esModule_is_reserved_as_an_exported_marker_when_transforming_ECMAScript_modules: DiagnosticMessage;
+        Export_assignment_is_not_supported_when_module_flag_is_system: DiagnosticMessage;
+        Experimental_support_for_decorators_is_a_feature_that_is_subject_to_change_in_a_future_release_Set_the_experimentalDecorators_option_to_remove_this_warning: DiagnosticMessage;
+        Generators_are_only_available_when_targeting_ECMAScript_2015_or_higher: DiagnosticMessage;
+        Generators_are_not_allowed_in_an_ambient_context: DiagnosticMessage;
+        An_overload_signature_cannot_be_declared_as_a_generator: DiagnosticMessage;
+        _0_tag_already_specified: DiagnosticMessage;
+        Signature_0_must_be_a_type_predicate: DiagnosticMessage;
+        Cannot_find_parameter_0: DiagnosticMessage;
+        Type_predicate_0_is_not_assignable_to_1: DiagnosticMessage;
+        Parameter_0_is_not_in_the_same_position_as_parameter_1: DiagnosticMessage;
+        A_type_predicate_is_only_allowed_in_return_type_position_for_functions_and_methods: DiagnosticMessage;
+        A_type_predicate_cannot_reference_a_rest_parameter: DiagnosticMessage;
+        A_type_predicate_cannot_reference_element_0_in_a_binding_pattern: DiagnosticMessage;
+        An_export_assignment_can_only_be_used_in_a_module: DiagnosticMessage;
+        An_import_declaration_can_only_be_used_in_a_namespace_or_module: DiagnosticMessage;
+        An_export_declaration_can_only_be_used_in_a_module: DiagnosticMessage;
+        An_ambient_module_declaration_is_only_allowed_at_the_top_level_in_a_file: DiagnosticMessage;
+        A_namespace_declaration_is_only_allowed_in_a_namespace_or_module: DiagnosticMessage;
+        The_return_type_of_a_property_decorator_function_must_be_either_void_or_any: DiagnosticMessage;
+        The_return_type_of_a_parameter_decorator_function_must_be_either_void_or_any: DiagnosticMessage;
+        Unable_to_resolve_signature_of_class_decorator_when_called_as_an_expression: DiagnosticMessage;
+        Unable_to_resolve_signature_of_parameter_decorator_when_called_as_an_expression: DiagnosticMessage;
+        Unable_to_resolve_signature_of_property_decorator_when_called_as_an_expression: DiagnosticMessage;
+        Unable_to_resolve_signature_of_method_decorator_when_called_as_an_expression: DiagnosticMessage;
+        abstract_modifier_can_only_appear_on_a_class_method_or_property_declaration: DiagnosticMessage;
+        _0_modifier_cannot_be_used_with_1_modifier: DiagnosticMessage;
+        Abstract_methods_can_only_appear_within_an_abstract_class: DiagnosticMessage;
+        Method_0_cannot_have_an_implementation_because_it_is_marked_abstract: DiagnosticMessage;
+        An_interface_property_cannot_have_an_initializer: DiagnosticMessage;
+        A_type_literal_property_cannot_have_an_initializer: DiagnosticMessage;
+        A_class_member_cannot_have_the_0_keyword: DiagnosticMessage;
+        A_decorator_can_only_decorate_a_method_implementation_not_an_overload: DiagnosticMessage;
+        Function_declarations_are_not_allowed_inside_blocks_in_strict_mode_when_targeting_ES3_or_ES5: DiagnosticMessage;
+        Function_declarations_are_not_allowed_inside_blocks_in_strict_mode_when_targeting_ES3_or_ES5_Class_definitions_are_automatically_in_strict_mode: DiagnosticMessage;
+        Function_declarations_are_not_allowed_inside_blocks_in_strict_mode_when_targeting_ES3_or_ES5_Modules_are_automatically_in_strict_mode: DiagnosticMessage;
+        _0_tag_cannot_be_used_independently_as_a_top_level_JSDoc_tag: DiagnosticMessage;
+        A_const_initializer_in_an_ambient_context_must_be_a_string_or_numeric_literal: DiagnosticMessage;
+        A_definite_assignment_assertion_is_not_permitted_in_this_context: DiagnosticMessage;
+        with_statements_are_not_allowed_in_an_async_function_block: DiagnosticMessage;
+        await_expression_is_only_allowed_within_an_async_function: DiagnosticMessage;
+        can_only_be_used_in_an_object_literal_property_inside_a_destructuring_assignment: DiagnosticMessage;
+        The_body_of_an_if_statement_cannot_be_the_empty_statement: DiagnosticMessage;
+        Global_module_exports_may_only_appear_in_module_files: DiagnosticMessage;
+        Global_module_exports_may_only_appear_in_declaration_files: DiagnosticMessage;
+        Global_module_exports_may_only_appear_at_top_level: DiagnosticMessage;
+        A_parameter_property_cannot_be_declared_using_a_rest_parameter: DiagnosticMessage;
+        An_abstract_accessor_cannot_have_an_implementation: DiagnosticMessage;
+        A_default_export_can_only_be_used_in_an_ECMAScript_style_module: DiagnosticMessage;
+        Type_of_await_operand_must_either_be_a_valid_promise_or_must_not_contain_a_callable_then_member: DiagnosticMessage;
+        Type_of_yield_operand_in_an_async_generator_must_either_be_a_valid_promise_or_must_not_contain_a_callable_then_member: DiagnosticMessage;
+        Type_of_iterated_elements_of_a_yield_Asterisk_operand_must_either_be_a_valid_promise_or_must_not_contain_a_callable_then_member: DiagnosticMessage;
+        Dynamic_import_is_only_supported_when_module_flag_is_commonjs_or_esNext: DiagnosticMessage;
+        Dynamic_import_must_have_one_specifier_as_an_argument: DiagnosticMessage;
+        Specifier_of_dynamic_import_cannot_be_spread_element: DiagnosticMessage;
+        Dynamic_import_cannot_have_type_arguments: DiagnosticMessage;
+        String_literal_with_double_quotes_expected: DiagnosticMessage;
+        Property_value_can_only_be_string_literal_numeric_literal_true_false_null_object_literal_or_array_literal: DiagnosticMessage;
+        _0_accepts_too_few_arguments_to_be_used_as_a_decorator_here_Did_you_mean_to_call_it_first_and_write_0: DiagnosticMessage;
+        A_property_of_an_interface_or_type_literal_whose_type_is_a_unique_symbol_type_must_be_readonly: DiagnosticMessage;
+        A_property_of_a_class_whose_type_is_a_unique_symbol_type_must_be_both_static_and_readonly: DiagnosticMessage;
+        A_variable_whose_type_is_a_unique_symbol_type_must_be_const: DiagnosticMessage;
+        unique_symbol_types_may_not_be_used_on_a_variable_declaration_with_a_binding_name: DiagnosticMessage;
+        unique_symbol_types_are_only_allowed_on_variables_in_a_variable_statement: DiagnosticMessage;
+        unique_symbol_types_are_not_allowed_here: DiagnosticMessage;
+        An_index_signature_parameter_type_cannot_be_a_type_alias_Consider_writing_0_Colon_1_Colon_2_instead: DiagnosticMessage;
+        An_index_signature_parameter_type_cannot_be_a_union_type_Consider_using_a_mapped_object_type_instead: DiagnosticMessage;
+        infer_declarations_are_only_permitted_in_the_extends_clause_of_a_conditional_type: DiagnosticMessage;
+        Module_0_does_not_refer_to_a_value_but_is_used_as_a_value_here: DiagnosticMessage;
+        Module_0_does_not_refer_to_a_type_but_is_used_as_a_type_here: DiagnosticMessage;
+        Type_arguments_cannot_be_used_here: DiagnosticMessage;
+        The_import_meta_meta_property_is_only_allowed_using_ESNext_for_the_target_and_module_compiler_options: DiagnosticMessage;
+        Duplicate_identifier_0: DiagnosticMessage;
+        Initializer_of_instance_member_variable_0_cannot_reference_identifier_1_declared_in_the_constructor: DiagnosticMessage;
+        Static_members_cannot_reference_class_type_parameters: DiagnosticMessage;
+        Circular_definition_of_import_alias_0: DiagnosticMessage;
+        Cannot_find_name_0: DiagnosticMessage;
+        Module_0_has_no_exported_member_1: DiagnosticMessage;
+        File_0_is_not_a_module: DiagnosticMessage;
+        Cannot_find_module_0: DiagnosticMessage;
+        Module_0_has_already_exported_a_member_named_1_Consider_explicitly_re_exporting_to_resolve_the_ambiguity: DiagnosticMessage;
+        An_export_assignment_cannot_be_used_in_a_module_with_other_exported_elements: DiagnosticMessage;
+        Type_0_recursively_references_itself_as_a_base_type: DiagnosticMessage;
+        A_class_may_only_extend_another_class: DiagnosticMessage;
+        An_interface_may_only_extend_a_class_or_another_interface: DiagnosticMessage;
+        Type_parameter_0_has_a_circular_constraint: DiagnosticMessage;
+        Generic_type_0_requires_1_type_argument_s: DiagnosticMessage;
+        Type_0_is_not_generic: DiagnosticMessage;
+        Global_type_0_must_be_a_class_or_interface_type: DiagnosticMessage;
+        Global_type_0_must_have_1_type_parameter_s: DiagnosticMessage;
+        Cannot_find_global_type_0: DiagnosticMessage;
+        Named_property_0_of_types_1_and_2_are_not_identical: DiagnosticMessage;
+        Interface_0_cannot_simultaneously_extend_types_1_and_2: DiagnosticMessage;
+        Excessive_stack_depth_comparing_types_0_and_1: DiagnosticMessage;
+        Type_0_is_not_assignable_to_type_1: DiagnosticMessage;
+        Cannot_redeclare_exported_variable_0: DiagnosticMessage;
+        Property_0_is_missing_in_type_1: DiagnosticMessage;
+        Property_0_is_private_in_type_1_but_not_in_type_2: DiagnosticMessage;
+        Types_of_property_0_are_incompatible: DiagnosticMessage;
+        Property_0_is_optional_in_type_1_but_required_in_type_2: DiagnosticMessage;
+        Types_of_parameters_0_and_1_are_incompatible: DiagnosticMessage;
+        Index_signature_is_missing_in_type_0: DiagnosticMessage;
+        Index_signatures_are_incompatible: DiagnosticMessage;
+        this_cannot_be_referenced_in_a_module_or_namespace_body: DiagnosticMessage;
+        this_cannot_be_referenced_in_current_location: DiagnosticMessage;
+        this_cannot_be_referenced_in_constructor_arguments: DiagnosticMessage;
+        this_cannot_be_referenced_in_a_static_property_initializer: DiagnosticMessage;
+        super_can_only_be_referenced_in_a_derived_class: DiagnosticMessage;
+        super_cannot_be_referenced_in_constructor_arguments: DiagnosticMessage;
+        Super_calls_are_not_permitted_outside_constructors_or_in_nested_functions_inside_constructors: DiagnosticMessage;
+        super_property_access_is_permitted_only_in_a_constructor_member_function_or_member_accessor_of_a_derived_class: DiagnosticMessage;
+        Property_0_does_not_exist_on_type_1: DiagnosticMessage;
+        Only_public_and_protected_methods_of_the_base_class_are_accessible_via_the_super_keyword: DiagnosticMessage;
+        Property_0_is_private_and_only_accessible_within_class_1: DiagnosticMessage;
+        An_index_expression_argument_must_be_of_type_string_number_symbol_or_any: DiagnosticMessage;
+        This_syntax_requires_an_imported_helper_named_1_but_module_0_has_no_exported_member_1: DiagnosticMessage;
+        Type_0_does_not_satisfy_the_constraint_1: DiagnosticMessage;
+        Argument_of_type_0_is_not_assignable_to_parameter_of_type_1: DiagnosticMessage;
+        Call_target_does_not_contain_any_signatures: DiagnosticMessage;
+        Untyped_function_calls_may_not_accept_type_arguments: DiagnosticMessage;
+        Value_of_type_0_is_not_callable_Did_you_mean_to_include_new: DiagnosticMessage;
+        Cannot_invoke_an_expression_whose_type_lacks_a_call_signature_Type_0_has_no_compatible_call_signatures: DiagnosticMessage;
+        Only_a_void_function_can_be_called_with_the_new_keyword: DiagnosticMessage;
+        Cannot_use_new_with_an_expression_whose_type_lacks_a_call_or_construct_signature: DiagnosticMessage;
+        Type_0_cannot_be_converted_to_type_1: DiagnosticMessage;
+        Object_literal_may_only_specify_known_properties_and_0_does_not_exist_in_type_1: DiagnosticMessage;
+        This_syntax_requires_an_imported_helper_but_module_0_cannot_be_found: DiagnosticMessage;
+        A_function_whose_declared_type_is_neither_void_nor_any_must_return_a_value: DiagnosticMessage;
+        An_arithmetic_operand_must_be_of_type_any_number_or_an_enum_type: DiagnosticMessage;
+        The_operand_of_an_increment_or_decrement_operator_must_be_a_variable_or_a_property_access: DiagnosticMessage;
+        The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: DiagnosticMessage;
+        The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_Function_interface_type: DiagnosticMessage;
+        The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol: DiagnosticMessage;
+        The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: DiagnosticMessage;
+        The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_or_an_enum_type: DiagnosticMessage;
+        The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_or_an_enum_type: DiagnosticMessage;
+        The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access: DiagnosticMessage;
+        Operator_0_cannot_be_applied_to_types_1_and_2: DiagnosticMessage;
+        Function_lacks_ending_return_statement_and_return_type_does_not_include_undefined: DiagnosticMessage;
+        Type_parameter_name_cannot_be_0: DiagnosticMessage;
+        A_parameter_property_is_only_allowed_in_a_constructor_implementation: DiagnosticMessage;
+        A_rest_parameter_must_be_of_an_array_type: DiagnosticMessage;
+        A_parameter_initializer_is_only_allowed_in_a_function_or_constructor_implementation: DiagnosticMessage;
+        Parameter_0_cannot_be_referenced_in_its_initializer: DiagnosticMessage;
+        Initializer_of_parameter_0_cannot_reference_identifier_1_declared_after_it: DiagnosticMessage;
+        Duplicate_string_index_signature: DiagnosticMessage;
+        Duplicate_number_index_signature: DiagnosticMessage;
+        A_super_call_must_be_the_first_statement_in_the_constructor_when_a_class_contains_initialized_properties_or_has_parameter_properties: DiagnosticMessage;
+        Constructors_for_derived_classes_must_contain_a_super_call: DiagnosticMessage;
+        A_get_accessor_must_return_a_value: DiagnosticMessage;
+        Getter_and_setter_accessors_do_not_agree_in_visibility: DiagnosticMessage;
+        get_and_set_accessor_must_have_the_same_type: DiagnosticMessage;
+        A_signature_with_an_implementation_cannot_use_a_string_literal_type: DiagnosticMessage;
+        Specialized_overload_signature_is_not_assignable_to_any_non_specialized_signature: DiagnosticMessage;
+        Overload_signatures_must_all_be_exported_or_non_exported: DiagnosticMessage;
+        Overload_signatures_must_all_be_ambient_or_non_ambient: DiagnosticMessage;
+        Overload_signatures_must_all_be_public_private_or_protected: DiagnosticMessage;
+        Overload_signatures_must_all_be_optional_or_required: DiagnosticMessage;
+        Function_overload_must_be_static: DiagnosticMessage;
+        Function_overload_must_not_be_static: DiagnosticMessage;
+        Function_implementation_name_must_be_0: DiagnosticMessage;
+        Constructor_implementation_is_missing: DiagnosticMessage;
+        Function_implementation_is_missing_or_not_immediately_following_the_declaration: DiagnosticMessage;
+        Multiple_constructor_implementations_are_not_allowed: DiagnosticMessage;
+        Duplicate_function_implementation: DiagnosticMessage;
+        Overload_signature_is_not_compatible_with_function_implementation: DiagnosticMessage;
+        Individual_declarations_in_merged_declaration_0_must_be_all_exported_or_all_local: DiagnosticMessage;
+        Duplicate_identifier_arguments_Compiler_uses_arguments_to_initialize_rest_parameters: DiagnosticMessage;
+        Declaration_name_conflicts_with_built_in_global_identifier_0: DiagnosticMessage;
+        Duplicate_identifier_this_Compiler_uses_variable_declaration_this_to_capture_this_reference: DiagnosticMessage;
+        Expression_resolves_to_variable_declaration_this_that_compiler_uses_to_capture_this_reference: DiagnosticMessage;
+        Duplicate_identifier_super_Compiler_uses_super_to_capture_base_class_reference: DiagnosticMessage;
+        Expression_resolves_to_super_that_compiler_uses_to_capture_base_class_reference: DiagnosticMessage;
+        Subsequent_variable_declarations_must_have_the_same_type_Variable_0_must_be_of_type_1_but_here_has_type_2: DiagnosticMessage;
+        The_left_hand_side_of_a_for_in_statement_cannot_use_a_type_annotation: DiagnosticMessage;
+        The_left_hand_side_of_a_for_in_statement_must_be_of_type_string_or_any: DiagnosticMessage;
+        The_left_hand_side_of_a_for_in_statement_must_be_a_variable_or_a_property_access: DiagnosticMessage;
+        The_right_hand_side_of_a_for_in_statement_must_be_of_type_any_an_object_type_or_a_type_parameter_but_here_has_type_0: DiagnosticMessage;
+        Setters_cannot_return_a_value: DiagnosticMessage;
+        Return_type_of_constructor_signature_must_be_assignable_to_the_instance_type_of_the_class: DiagnosticMessage;
+        The_with_statement_is_not_supported_All_symbols_in_a_with_block_will_have_type_any: DiagnosticMessage;
+        Property_0_of_type_1_is_not_assignable_to_string_index_type_2: DiagnosticMessage;
+        Property_0_of_type_1_is_not_assignable_to_numeric_index_type_2: DiagnosticMessage;
+        Numeric_index_type_0_is_not_assignable_to_string_index_type_1: DiagnosticMessage;
+        Class_name_cannot_be_0: DiagnosticMessage;
+        Class_0_incorrectly_extends_base_class_1: DiagnosticMessage;
+        Property_0_in_type_1_is_not_assignable_to_the_same_property_in_base_type_2: DiagnosticMessage;
+        Class_static_side_0_incorrectly_extends_base_class_static_side_1: DiagnosticMessage;
+        Class_0_incorrectly_implements_interface_1: DiagnosticMessage;
+        A_class_may_only_implement_another_class_or_interface: DiagnosticMessage;
+        Class_0_defines_instance_member_function_1_but_extended_class_2_defines_it_as_instance_member_accessor: DiagnosticMessage;
+        Class_0_defines_instance_member_function_1_but_extended_class_2_defines_it_as_instance_member_property: DiagnosticMessage;
+        Class_0_defines_instance_member_property_1_but_extended_class_2_defines_it_as_instance_member_function: DiagnosticMessage;
+        Class_0_defines_instance_member_accessor_1_but_extended_class_2_defines_it_as_instance_member_function: DiagnosticMessage;
+        Interface_name_cannot_be_0: DiagnosticMessage;
+        All_declarations_of_0_must_have_identical_type_parameters: DiagnosticMessage;
+        Interface_0_incorrectly_extends_interface_1: DiagnosticMessage;
+        Enum_name_cannot_be_0: DiagnosticMessage;
+        In_an_enum_with_multiple_declarations_only_one_declaration_can_omit_an_initializer_for_its_first_enum_element: DiagnosticMessage;
+        A_namespace_declaration_cannot_be_in_a_different_file_from_a_class_or_function_with_which_it_is_merged: DiagnosticMessage;
+        A_namespace_declaration_cannot_be_located_prior_to_a_class_or_function_with_which_it_is_merged: DiagnosticMessage;
+        Ambient_modules_cannot_be_nested_in_other_modules_or_namespaces: DiagnosticMessage;
+        Ambient_module_declaration_cannot_specify_relative_module_name: DiagnosticMessage;
+        Module_0_is_hidden_by_a_local_declaration_with_the_same_name: DiagnosticMessage;
+        Import_name_cannot_be_0: DiagnosticMessage;
+        Import_or_export_declaration_in_an_ambient_module_declaration_cannot_reference_module_through_relative_module_name: DiagnosticMessage;
+        Import_declaration_conflicts_with_local_declaration_of_0: DiagnosticMessage;
+        Duplicate_identifier_0_Compiler_reserves_name_1_in_top_level_scope_of_a_module: DiagnosticMessage;
+        Types_have_separate_declarations_of_a_private_property_0: DiagnosticMessage;
+        Property_0_is_protected_but_type_1_is_not_a_class_derived_from_2: DiagnosticMessage;
+        Property_0_is_protected_in_type_1_but_public_in_type_2: DiagnosticMessage;
+        Property_0_is_protected_and_only_accessible_within_class_1_and_its_subclasses: DiagnosticMessage;
+        Property_0_is_protected_and_only_accessible_through_an_instance_of_class_1: DiagnosticMessage;
+        The_0_operator_is_not_allowed_for_boolean_types_Consider_using_1_instead: DiagnosticMessage;
+        Block_scoped_variable_0_used_before_its_declaration: DiagnosticMessage;
+        Class_0_used_before_its_declaration: DiagnosticMessage;
+        Enum_0_used_before_its_declaration: DiagnosticMessage;
+        Cannot_redeclare_block_scoped_variable_0: DiagnosticMessage;
+        An_enum_member_cannot_have_a_numeric_name: DiagnosticMessage;
+        The_type_argument_for_type_parameter_0_cannot_be_inferred_from_the_usage_Consider_specifying_the_type_arguments_explicitly: DiagnosticMessage;
+        Variable_0_is_used_before_being_assigned: DiagnosticMessage;
+        Type_argument_candidate_1_is_not_a_valid_type_argument_because_it_is_not_a_supertype_of_candidate_0: DiagnosticMessage;
+        Type_alias_0_circularly_references_itself: DiagnosticMessage;
+        Type_alias_name_cannot_be_0: DiagnosticMessage;
+        An_AMD_module_cannot_have_multiple_name_assignments: DiagnosticMessage;
+        Type_0_has_no_property_1_and_no_string_index_signature: DiagnosticMessage;
+        Type_0_has_no_property_1: DiagnosticMessage;
+        Type_0_is_not_an_array_type: DiagnosticMessage;
+        A_rest_element_must_be_last_in_a_destructuring_pattern: DiagnosticMessage;
+        A_binding_pattern_parameter_cannot_be_optional_in_an_implementation_signature: DiagnosticMessage;
+        A_computed_property_name_must_be_of_type_string_number_symbol_or_any: DiagnosticMessage;
+        this_cannot_be_referenced_in_a_computed_property_name: DiagnosticMessage;
+        super_cannot_be_referenced_in_a_computed_property_name: DiagnosticMessage;
+        A_computed_property_name_cannot_reference_a_type_parameter_from_its_containing_type: DiagnosticMessage;
+        Cannot_find_global_value_0: DiagnosticMessage;
+        The_0_operator_cannot_be_applied_to_type_symbol: DiagnosticMessage;
+        Symbol_reference_does_not_refer_to_the_global_Symbol_constructor_object: DiagnosticMessage;
+        A_computed_property_name_of_the_form_0_must_be_of_type_symbol: DiagnosticMessage;
+        Spread_operator_in_new_expressions_is_only_available_when_targeting_ECMAScript_5_and_higher: DiagnosticMessage;
+        Enum_declarations_must_all_be_const_or_non_const: DiagnosticMessage;
+        In_const_enum_declarations_member_initializer_must_be_constant_expression: DiagnosticMessage;
+        const_enums_can_only_be_used_in_property_or_index_access_expressions_or_the_right_hand_side_of_an_import_declaration_or_export_assignment_or_type_query: DiagnosticMessage;
+        A_const_enum_member_can_only_be_accessed_using_a_string_literal: DiagnosticMessage;
+        const_enum_member_initializer_was_evaluated_to_a_non_finite_value: DiagnosticMessage;
+        const_enum_member_initializer_was_evaluated_to_disallowed_value_NaN: DiagnosticMessage;
+        Property_0_does_not_exist_on_const_enum_1: DiagnosticMessage;
+        let_is_not_allowed_to_be_used_as_a_name_in_let_or_const_declarations: DiagnosticMessage;
+        Cannot_initialize_outer_scoped_variable_0_in_the_same_scope_as_block_scoped_declaration_1: DiagnosticMessage;
+        The_left_hand_side_of_a_for_of_statement_cannot_use_a_type_annotation: DiagnosticMessage;
+        Export_declaration_conflicts_with_exported_declaration_of_0: DiagnosticMessage;
+        The_left_hand_side_of_a_for_of_statement_must_be_a_variable_or_a_property_access: DiagnosticMessage;
+        Type_0_must_have_a_Symbol_iterator_method_that_returns_an_iterator: DiagnosticMessage;
+        An_iterator_must_have_a_next_method: DiagnosticMessage;
+        The_type_returned_by_the_next_method_of_an_iterator_must_have_a_value_property: DiagnosticMessage;
+        The_left_hand_side_of_a_for_in_statement_cannot_be_a_destructuring_pattern: DiagnosticMessage;
+        Cannot_redeclare_identifier_0_in_catch_clause: DiagnosticMessage;
+        Tuple_type_0_with_length_1_cannot_be_assigned_to_tuple_with_length_2: DiagnosticMessage;
+        Using_a_string_in_a_for_of_statement_is_only_supported_in_ECMAScript_5_and_higher: DiagnosticMessage;
+        Type_0_is_not_an_array_type_or_a_string_type: DiagnosticMessage;
+        The_arguments_object_cannot_be_referenced_in_an_arrow_function_in_ES3_and_ES5_Consider_using_a_standard_function_expression: DiagnosticMessage;
+        Module_0_resolves_to_a_non_module_entity_and_cannot_be_imported_using_this_construct: DiagnosticMessage;
+        Module_0_uses_export_and_cannot_be_used_with_export_Asterisk: DiagnosticMessage;
+        An_interface_can_only_extend_an_identifier_Slashqualified_name_with_optional_type_arguments: DiagnosticMessage;
+        A_class_can_only_implement_an_identifier_Slashqualified_name_with_optional_type_arguments: DiagnosticMessage;
+        A_rest_element_cannot_contain_a_binding_pattern: DiagnosticMessage;
+        _0_is_referenced_directly_or_indirectly_in_its_own_type_annotation: DiagnosticMessage;
+        Cannot_find_namespace_0: DiagnosticMessage;
+        Type_0_must_have_a_Symbol_asyncIterator_method_that_returns_an_async_iterator: DiagnosticMessage;
+        A_generator_cannot_have_a_void_type_annotation: DiagnosticMessage;
+        _0_is_referenced_directly_or_indirectly_in_its_own_base_expression: DiagnosticMessage;
+        Type_0_is_not_a_constructor_function_type: DiagnosticMessage;
+        No_base_constructor_has_the_specified_number_of_type_arguments: DiagnosticMessage;
+        Base_constructor_return_type_0_is_not_a_class_or_interface_type: DiagnosticMessage;
+        Base_constructors_must_all_have_the_same_return_type: DiagnosticMessage;
+        Cannot_create_an_instance_of_an_abstract_class: DiagnosticMessage;
+        Overload_signatures_must_all_be_abstract_or_non_abstract: DiagnosticMessage;
+        Abstract_method_0_in_class_1_cannot_be_accessed_via_super_expression: DiagnosticMessage;
+        Classes_containing_abstract_methods_must_be_marked_abstract: DiagnosticMessage;
+        Non_abstract_class_0_does_not_implement_inherited_abstract_member_1_from_class_2: DiagnosticMessage;
+        All_declarations_of_an_abstract_method_must_be_consecutive: DiagnosticMessage;
+        Cannot_assign_an_abstract_constructor_type_to_a_non_abstract_constructor_type: DiagnosticMessage;
+        A_this_based_type_guard_is_not_compatible_with_a_parameter_based_type_guard: DiagnosticMessage;
+        An_async_iterator_must_have_a_next_method: DiagnosticMessage;
+        Duplicate_identifier_0_Compiler_uses_declaration_1_to_support_async_functions: DiagnosticMessage;
+        Expression_resolves_to_variable_declaration_0_that_compiler_uses_to_support_async_functions: DiagnosticMessage;
+        The_arguments_object_cannot_be_referenced_in_an_async_function_or_method_in_ES3_and_ES5_Consider_using_a_standard_function_or_method: DiagnosticMessage;
+        yield_expressions_cannot_be_used_in_a_parameter_initializer: DiagnosticMessage;
+        await_expressions_cannot_be_used_in_a_parameter_initializer: DiagnosticMessage;
+        Initializer_provides_no_value_for_this_binding_element_and_the_binding_element_has_no_default_value: DiagnosticMessage;
+        A_this_type_is_available_only_in_a_non_static_member_of_a_class_or_interface: DiagnosticMessage;
+        The_inferred_type_of_0_references_an_inaccessible_1_type_A_type_annotation_is_necessary: DiagnosticMessage;
+        A_module_cannot_have_multiple_default_exports: DiagnosticMessage;
+        Duplicate_identifier_0_Compiler_reserves_name_1_in_top_level_scope_of_a_module_containing_async_functions: DiagnosticMessage;
+        Property_0_is_incompatible_with_index_signature: DiagnosticMessage;
+        Object_is_possibly_null: DiagnosticMessage;
+        Object_is_possibly_undefined: DiagnosticMessage;
+        Object_is_possibly_null_or_undefined: DiagnosticMessage;
+        A_function_returning_never_cannot_have_a_reachable_end_point: DiagnosticMessage;
+        Enum_type_0_has_members_with_initializers_that_are_not_literals: DiagnosticMessage;
+        Type_0_cannot_be_used_to_index_type_1: DiagnosticMessage;
+        Type_0_has_no_matching_index_signature_for_type_1: DiagnosticMessage;
+        Type_0_cannot_be_used_as_an_index_type: DiagnosticMessage;
+        Cannot_assign_to_0_because_it_is_not_a_variable: DiagnosticMessage;
+        Cannot_assign_to_0_because_it_is_a_constant_or_a_read_only_property: DiagnosticMessage;
+        The_target_of_an_assignment_must_be_a_variable_or_a_property_access: DiagnosticMessage;
+        Index_signature_in_type_0_only_permits_reading: DiagnosticMessage;
+        Duplicate_identifier_newTarget_Compiler_uses_variable_declaration_newTarget_to_capture_new_target_meta_property_reference: DiagnosticMessage;
+        Expression_resolves_to_variable_declaration_newTarget_that_compiler_uses_to_capture_new_target_meta_property_reference: DiagnosticMessage;
+        A_mixin_class_must_have_a_constructor_with_a_single_rest_parameter_of_type_any: DiagnosticMessage;
+        Property_0_has_conflicting_declarations_and_is_inaccessible_in_type_1: DiagnosticMessage;
+        The_type_returned_by_the_next_method_of_an_async_iterator_must_be_a_promise_for_a_type_with_a_value_property: DiagnosticMessage;
+        Type_0_is_not_an_array_type_or_does_not_have_a_Symbol_iterator_method_that_returns_an_iterator: DiagnosticMessage;
+        Type_0_is_not_an_array_type_or_a_string_type_or_does_not_have_a_Symbol_iterator_method_that_returns_an_iterator: DiagnosticMessage;
+        Generic_type_instantiation_is_excessively_deep_and_possibly_infinite: DiagnosticMessage;
+        Property_0_does_not_exist_on_type_1_Did_you_mean_2: DiagnosticMessage;
+        Cannot_find_name_0_Did_you_mean_1: DiagnosticMessage;
+        Computed_values_are_not_permitted_in_an_enum_with_string_valued_members: DiagnosticMessage;
+        Expected_0_arguments_but_got_1: DiagnosticMessage;
+        Expected_at_least_0_arguments_but_got_1: DiagnosticMessage;
+        Expected_0_arguments_but_got_1_or_more: DiagnosticMessage;
+        Expected_at_least_0_arguments_but_got_1_or_more: DiagnosticMessage;
+        Expected_0_type_arguments_but_got_1: DiagnosticMessage;
+        Type_0_has_no_properties_in_common_with_type_1: DiagnosticMessage;
+        Value_of_type_0_has_no_properties_in_common_with_type_1_Did_you_mean_to_call_it: DiagnosticMessage;
+        Object_literal_may_only_specify_known_properties_but_0_does_not_exist_in_type_1_Did_you_mean_to_write_2: DiagnosticMessage;
+        Base_class_expressions_cannot_reference_class_type_parameters: DiagnosticMessage;
+        The_containing_function_or_module_body_is_too_large_for_control_flow_analysis: DiagnosticMessage;
+        Property_0_has_no_initializer_and_is_not_definitely_assigned_in_the_constructor: DiagnosticMessage;
+        Property_0_is_used_before_being_assigned: DiagnosticMessage;
+        A_rest_element_cannot_have_a_property_name: DiagnosticMessage;
+        Enum_declarations_can_only_merge_with_namespace_or_other_enum_declarations: DiagnosticMessage;
+        Type_0_is_not_an_array_type_Use_compiler_option_downlevelIteration_to_allow_iterating_of_iterators: DiagnosticMessage;
+        Type_0_is_not_an_array_type_or_a_string_type_Use_compiler_option_downlevelIteration_to_allow_iterating_of_iterators: DiagnosticMessage;
+        Property_0_does_not_exist_on_type_1_Did_you_forget_to_use_await: DiagnosticMessage;
+        Object_is_of_type_unknown: DiagnosticMessage;
+        JSX_element_attributes_type_0_may_not_be_a_union_type: DiagnosticMessage;
+        The_return_type_of_a_JSX_element_constructor_must_return_an_object_type: DiagnosticMessage;
+        JSX_element_implicitly_has_type_any_because_the_global_type_JSX_Element_does_not_exist: DiagnosticMessage;
+        Property_0_in_type_1_is_not_assignable_to_type_2: DiagnosticMessage;
+        JSX_element_type_0_does_not_have_any_construct_or_call_signatures: DiagnosticMessage;
+        JSX_element_type_0_is_not_a_constructor_function_for_JSX_elements: DiagnosticMessage;
+        Property_0_of_JSX_spread_attribute_is_not_assignable_to_target_property: DiagnosticMessage;
+        JSX_element_class_does_not_support_attributes_because_it_does_not_have_a_0_property: DiagnosticMessage;
+        The_global_type_JSX_0_may_not_have_more_than_one_property: DiagnosticMessage;
+        JSX_spread_child_must_be_an_array_type: DiagnosticMessage;
+        Cannot_augment_module_0_with_value_exports_because_it_resolves_to_a_non_module_entity: DiagnosticMessage;
+        A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_members_defined_in_other_enums: DiagnosticMessage;
+        Merged_declaration_0_cannot_include_a_default_export_declaration_Consider_adding_a_separate_export_default_0_declaration_instead: DiagnosticMessage;
+        Non_abstract_class_expression_does_not_implement_inherited_abstract_member_0_from_class_1: DiagnosticMessage;
+        Exported_external_package_typings_file_cannot_contain_tripleslash_references_Please_contact_the_package_author_to_update_the_package_definition: DiagnosticMessage;
+        Exported_external_package_typings_file_0_is_not_a_module_Please_contact_the_package_author_to_update_the_package_definition: DiagnosticMessage;
+        JSX_expressions_must_have_one_parent_element: DiagnosticMessage;
+        Type_0_provides_no_match_for_the_signature_1: DiagnosticMessage;
+        super_is_only_allowed_in_members_of_object_literal_expressions_when_option_target_is_ES2015_or_higher: DiagnosticMessage;
+        super_can_only_be_referenced_in_members_of_derived_classes_or_object_literal_expressions: DiagnosticMessage;
+        Cannot_export_0_Only_local_declarations_can_be_exported_from_a_module: DiagnosticMessage;
+        Cannot_find_name_0_Did_you_mean_the_static_member_1_0: DiagnosticMessage;
+        Cannot_find_name_0_Did_you_mean_the_instance_member_this_0: DiagnosticMessage;
+        Invalid_module_name_in_augmentation_module_0_cannot_be_found: DiagnosticMessage;
+        Invalid_module_name_in_augmentation_Module_0_resolves_to_an_untyped_module_at_1_which_cannot_be_augmented: DiagnosticMessage;
+        Exports_and_export_assignments_are_not_permitted_in_module_augmentations: DiagnosticMessage;
+        Imports_are_not_permitted_in_module_augmentations_Consider_moving_them_to_the_enclosing_external_module: DiagnosticMessage;
+        export_modifier_cannot_be_applied_to_ambient_modules_and_module_augmentations_since_they_are_always_visible: DiagnosticMessage;
+        Augmentations_for_the_global_scope_can_only_be_directly_nested_in_external_modules_or_ambient_module_declarations: DiagnosticMessage;
+        Augmentations_for_the_global_scope_should_have_declare_modifier_unless_they_appear_in_already_ambient_context: DiagnosticMessage;
+        Cannot_augment_module_0_because_it_resolves_to_a_non_module_entity: DiagnosticMessage;
+        Cannot_assign_a_0_constructor_type_to_a_1_constructor_type: DiagnosticMessage;
+        Constructor_of_class_0_is_private_and_only_accessible_within_the_class_declaration: DiagnosticMessage;
+        Constructor_of_class_0_is_protected_and_only_accessible_within_the_class_declaration: DiagnosticMessage;
+        Cannot_extend_a_class_0_Class_constructor_is_marked_as_private: DiagnosticMessage;
+        Accessors_must_both_be_abstract_or_non_abstract: DiagnosticMessage;
+        A_type_predicate_s_type_must_be_assignable_to_its_parameter_s_type: DiagnosticMessage;
+        Type_0_is_not_comparable_to_type_1: DiagnosticMessage;
+        A_function_that_is_called_with_the_new_keyword_cannot_have_a_this_type_that_is_void: DiagnosticMessage;
+        A_0_parameter_must_be_the_first_parameter: DiagnosticMessage;
+        A_constructor_cannot_have_a_this_parameter: DiagnosticMessage;
+        get_and_set_accessor_must_have_the_same_this_type: DiagnosticMessage;
+        this_implicitly_has_type_any_because_it_does_not_have_a_type_annotation: DiagnosticMessage;
+        The_this_context_of_type_0_is_not_assignable_to_method_s_this_of_type_1: DiagnosticMessage;
+        The_this_types_of_each_signature_are_incompatible: DiagnosticMessage;
+        _0_refers_to_a_UMD_global_but_the_current_file_is_a_module_Consider_adding_an_import_instead: DiagnosticMessage;
+        All_declarations_of_0_must_have_identical_modifiers: DiagnosticMessage;
+        Cannot_find_type_definition_file_for_0: DiagnosticMessage;
+        Cannot_extend_an_interface_0_Did_you_mean_implements: DiagnosticMessage;
+        An_import_path_cannot_end_with_a_0_extension_Consider_importing_1_instead: DiagnosticMessage;
+        _0_is_a_primitive_but_1_is_a_wrapper_object_Prefer_using_0_when_possible: DiagnosticMessage;
+        _0_only_refers_to_a_type_but_is_being_used_as_a_value_here: DiagnosticMessage;
+        Namespace_0_has_no_exported_member_1: DiagnosticMessage;
+        Left_side_of_comma_operator_is_unused_and_has_no_side_effects: DiagnosticMessage;
+        The_Object_type_is_assignable_to_very_few_other_types_Did_you_mean_to_use_the_any_type_instead: DiagnosticMessage;
+        An_async_function_or_method_must_return_a_Promise_Make_sure_you_have_a_declaration_for_Promise_or_include_ES2015_in_your_lib_option: DiagnosticMessage;
+        Spread_types_may_only_be_created_from_object_types: DiagnosticMessage;
+        Static_property_0_conflicts_with_built_in_property_Function_0_of_constructor_function_1: DiagnosticMessage;
+        Rest_types_may_only_be_created_from_object_types: DiagnosticMessage;
+        The_target_of_an_object_rest_assignment_must_be_a_variable_or_a_property_access: DiagnosticMessage;
+        _0_only_refers_to_a_type_but_is_being_used_as_a_namespace_here: DiagnosticMessage;
+        The_operand_of_a_delete_operator_must_be_a_property_reference: DiagnosticMessage;
+        The_operand_of_a_delete_operator_cannot_be_a_read_only_property: DiagnosticMessage;
+        An_async_function_or_method_in_ES5_SlashES3_requires_the_Promise_constructor_Make_sure_you_have_a_declaration_for_the_Promise_constructor_or_include_ES2015_in_your_lib_option: DiagnosticMessage;
+        Required_type_parameters_may_not_follow_optional_type_parameters: DiagnosticMessage;
+        Generic_type_0_requires_between_1_and_2_type_arguments: DiagnosticMessage;
+        Cannot_use_namespace_0_as_a_value: DiagnosticMessage;
+        Cannot_use_namespace_0_as_a_type: DiagnosticMessage;
+        _0_are_specified_twice_The_attribute_named_0_will_be_overwritten: DiagnosticMessage;
+        A_dynamic_import_call_returns_a_Promise_Make_sure_you_have_a_declaration_for_Promise_or_include_ES2015_in_your_lib_option: DiagnosticMessage;
+        A_dynamic_import_call_in_ES5_SlashES3_requires_the_Promise_constructor_Make_sure_you_have_a_declaration_for_the_Promise_constructor_or_include_ES2015_in_your_lib_option: DiagnosticMessage;
+        Cannot_access_0_1_because_0_is_a_type_but_not_a_namespace_Did_you_mean_to_retrieve_the_type_of_the_property_1_in_0_with_0_1: DiagnosticMessage;
+        The_expression_of_an_export_assignment_must_be_an_identifier_or_qualified_name_in_an_ambient_context: DiagnosticMessage;
+        Abstract_property_0_in_class_1_cannot_be_accessed_in_the_constructor: DiagnosticMessage;
+        Type_parameter_0_has_a_circular_default: DiagnosticMessage;
+        Subsequent_property_declarations_must_have_the_same_type_Property_0_must_be_of_type_1_but_here_has_type_2: DiagnosticMessage;
+        Duplicate_declaration_0: DiagnosticMessage;
+        Type_0_is_not_assignable_to_type_1_Two_different_types_with_this_name_exist_but_they_are_unrelated: DiagnosticMessage;
+        Class_0_incorrectly_implements_class_1_Did_you_mean_to_extend_1_and_inherit_its_members_as_a_subclass: DiagnosticMessage;
+        Cannot_invoke_an_object_which_is_possibly_null: DiagnosticMessage;
+        Cannot_invoke_an_object_which_is_possibly_undefined: DiagnosticMessage;
+        Cannot_invoke_an_object_which_is_possibly_null_or_undefined: DiagnosticMessage;
+        Module_0_has_no_exported_member_1_Did_you_mean_2: DiagnosticMessage;
+        Class_name_cannot_be_Object_when_targeting_ES5_with_module_0: DiagnosticMessage;
+        Cannot_find_lib_definition_for_0: DiagnosticMessage;
+        Cannot_find_lib_definition_for_0_Did_you_mean_1: DiagnosticMessage;
+        Import_declaration_0_is_using_private_name_1: DiagnosticMessage;
+        Type_parameter_0_of_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
+        Type_parameter_0_of_exported_interface_has_or_is_using_private_name_1: DiagnosticMessage;
+        Type_parameter_0_of_constructor_signature_from_exported_interface_has_or_is_using_private_name_1: DiagnosticMessage;
+        Type_parameter_0_of_call_signature_from_exported_interface_has_or_is_using_private_name_1: DiagnosticMessage;
+        Type_parameter_0_of_public_static_method_from_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
+        Type_parameter_0_of_public_method_from_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
+        Type_parameter_0_of_method_from_exported_interface_has_or_is_using_private_name_1: DiagnosticMessage;
+        Type_parameter_0_of_exported_function_has_or_is_using_private_name_1: DiagnosticMessage;
+        Implements_clause_of_exported_class_0_has_or_is_using_private_name_1: DiagnosticMessage;
+        extends_clause_of_exported_class_0_has_or_is_using_private_name_1: DiagnosticMessage;
+        extends_clause_of_exported_interface_0_has_or_is_using_private_name_1: DiagnosticMessage;
+        Exported_variable_0_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named: DiagnosticMessage;
+        Exported_variable_0_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Exported_variable_0_has_or_is_using_private_name_1: DiagnosticMessage;
+        Public_static_property_0_of_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named: DiagnosticMessage;
+        Public_static_property_0_of_exported_class_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Public_static_property_0_of_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
+        Public_property_0_of_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named: DiagnosticMessage;
+        Public_property_0_of_exported_class_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Public_property_0_of_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
+        Property_0_of_exported_interface_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Property_0_of_exported_interface_has_or_is_using_private_name_1: DiagnosticMessage;
+        Parameter_type_of_public_static_setter_0_from_exported_class_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Parameter_type_of_public_static_setter_0_from_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
+        Parameter_type_of_public_setter_0_from_exported_class_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Parameter_type_of_public_setter_0_from_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
+        Return_type_of_public_static_getter_0_from_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named: DiagnosticMessage;
+        Return_type_of_public_static_getter_0_from_exported_class_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Return_type_of_public_static_getter_0_from_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
+        Return_type_of_public_getter_0_from_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named: DiagnosticMessage;
+        Return_type_of_public_getter_0_from_exported_class_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Return_type_of_public_getter_0_from_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
+        Return_type_of_constructor_signature_from_exported_interface_has_or_is_using_name_0_from_private_module_1: DiagnosticMessage;
+        Return_type_of_constructor_signature_from_exported_interface_has_or_is_using_private_name_0: DiagnosticMessage;
+        Return_type_of_call_signature_from_exported_interface_has_or_is_using_name_0_from_private_module_1: DiagnosticMessage;
+        Return_type_of_call_signature_from_exported_interface_has_or_is_using_private_name_0: DiagnosticMessage;
+        Return_type_of_index_signature_from_exported_interface_has_or_is_using_name_0_from_private_module_1: DiagnosticMessage;
+        Return_type_of_index_signature_from_exported_interface_has_or_is_using_private_name_0: DiagnosticMessage;
+        Return_type_of_public_static_method_from_exported_class_has_or_is_using_name_0_from_external_module_1_but_cannot_be_named: DiagnosticMessage;
+        Return_type_of_public_static_method_from_exported_class_has_or_is_using_name_0_from_private_module_1: DiagnosticMessage;
+        Return_type_of_public_static_method_from_exported_class_has_or_is_using_private_name_0: DiagnosticMessage;
+        Return_type_of_public_method_from_exported_class_has_or_is_using_name_0_from_external_module_1_but_cannot_be_named: DiagnosticMessage;
+        Return_type_of_public_method_from_exported_class_has_or_is_using_name_0_from_private_module_1: DiagnosticMessage;
+        Return_type_of_public_method_from_exported_class_has_or_is_using_private_name_0: DiagnosticMessage;
+        Return_type_of_method_from_exported_interface_has_or_is_using_name_0_from_private_module_1: DiagnosticMessage;
+        Return_type_of_method_from_exported_interface_has_or_is_using_private_name_0: DiagnosticMessage;
+        Return_type_of_exported_function_has_or_is_using_name_0_from_external_module_1_but_cannot_be_named: DiagnosticMessage;
+        Return_type_of_exported_function_has_or_is_using_name_0_from_private_module_1: DiagnosticMessage;
+        Return_type_of_exported_function_has_or_is_using_private_name_0: DiagnosticMessage;
+        Parameter_0_of_constructor_from_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named: DiagnosticMessage;
+        Parameter_0_of_constructor_from_exported_class_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Parameter_0_of_constructor_from_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
+        Parameter_0_of_constructor_signature_from_exported_interface_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Parameter_0_of_constructor_signature_from_exported_interface_has_or_is_using_private_name_1: DiagnosticMessage;
+        Parameter_0_of_call_signature_from_exported_interface_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Parameter_0_of_call_signature_from_exported_interface_has_or_is_using_private_name_1: DiagnosticMessage;
+        Parameter_0_of_public_static_method_from_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named: DiagnosticMessage;
+        Parameter_0_of_public_static_method_from_exported_class_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Parameter_0_of_public_static_method_from_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
+        Parameter_0_of_public_method_from_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named: DiagnosticMessage;
+        Parameter_0_of_public_method_from_exported_class_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Parameter_0_of_public_method_from_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
+        Parameter_0_of_method_from_exported_interface_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Parameter_0_of_method_from_exported_interface_has_or_is_using_private_name_1: DiagnosticMessage;
+        Parameter_0_of_exported_function_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named: DiagnosticMessage;
+        Parameter_0_of_exported_function_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Parameter_0_of_exported_function_has_or_is_using_private_name_1: DiagnosticMessage;
+        Exported_type_alias_0_has_or_is_using_private_name_1: DiagnosticMessage;
+        Default_export_of_the_module_has_or_is_using_private_name_0: DiagnosticMessage;
+        Type_parameter_0_of_exported_type_alias_has_or_is_using_private_name_1: DiagnosticMessage;
+        Conflicting_definitions_for_0_found_at_1_and_2_Consider_installing_a_specific_version_of_this_library_to_resolve_the_conflict: DiagnosticMessage;
+        Parameter_0_of_index_signature_from_exported_interface_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Parameter_0_of_index_signature_from_exported_interface_has_or_is_using_private_name_1: DiagnosticMessage;
+        Property_0_of_exported_class_expression_may_not_be_private_or_protected: DiagnosticMessage;
+        Public_static_method_0_of_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named: DiagnosticMessage;
+        Public_static_method_0_of_exported_class_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Public_static_method_0_of_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
+        Public_method_0_of_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named: DiagnosticMessage;
+        Public_method_0_of_exported_class_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Public_method_0_of_exported_class_has_or_is_using_private_name_1: DiagnosticMessage;
+        Method_0_of_exported_interface_has_or_is_using_name_1_from_private_module_2: DiagnosticMessage;
+        Method_0_of_exported_interface_has_or_is_using_private_name_1: DiagnosticMessage;
+        The_current_host_does_not_support_the_0_option: DiagnosticMessage;
+        Cannot_find_the_common_subdirectory_path_for_the_input_files: DiagnosticMessage;
+        File_specification_cannot_end_in_a_recursive_directory_wildcard_Asterisk_Asterisk_Colon_0: DiagnosticMessage;
+        Cannot_read_file_0_Colon_1: DiagnosticMessage;
+        Failed_to_parse_file_0_Colon_1: DiagnosticMessage;
+        Unknown_compiler_option_0: DiagnosticMessage;
+        Compiler_option_0_requires_a_value_of_type_1: DiagnosticMessage;
+        Could_not_write_file_0_Colon_1: DiagnosticMessage;
+        Option_project_cannot_be_mixed_with_source_files_on_a_command_line: DiagnosticMessage;
+        Option_isolatedModules_can_only_be_used_when_either_option_module_is_provided_or_option_target_is_ES2015_or_higher: DiagnosticMessage;
+        Option_0_can_only_be_used_when_either_option_inlineSourceMap_or_option_sourceMap_is_provided: DiagnosticMessage;
+        Option_0_cannot_be_specified_without_specifying_option_1: DiagnosticMessage;
+        Option_0_cannot_be_specified_with_option_1: DiagnosticMessage;
+        A_tsconfig_json_file_is_already_defined_at_Colon_0: DiagnosticMessage;
+        Cannot_write_file_0_because_it_would_overwrite_input_file: DiagnosticMessage;
+        Cannot_write_file_0_because_it_would_be_overwritten_by_multiple_input_files: DiagnosticMessage;
+        Cannot_find_a_tsconfig_json_file_at_the_specified_directory_Colon_0: DiagnosticMessage;
+        The_specified_path_does_not_exist_Colon_0: DiagnosticMessage;
+        Invalid_value_for_reactNamespace_0_is_not_a_valid_identifier: DiagnosticMessage;
+        Option_paths_cannot_be_used_without_specifying_baseUrl_option: DiagnosticMessage;
+        Pattern_0_can_have_at_most_one_Asterisk_character: DiagnosticMessage;
+        Substitution_0_in_pattern_1_in_can_have_at_most_one_Asterisk_character: DiagnosticMessage;
+        Substitutions_for_pattern_0_should_be_an_array: DiagnosticMessage;
+        Substitution_0_for_pattern_1_has_incorrect_type_expected_string_got_2: DiagnosticMessage;
+        File_specification_cannot_contain_a_parent_directory_that_appears_after_a_recursive_directory_wildcard_Asterisk_Asterisk_Colon_0: DiagnosticMessage;
+        Substitutions_for_pattern_0_shouldn_t_be_an_empty_array: DiagnosticMessage;
+        Invalid_value_for_jsxFactory_0_is_not_a_valid_identifier_or_qualified_name: DiagnosticMessage;
+        Adding_a_tsconfig_json_file_will_help_organize_projects_that_contain_both_TypeScript_and_JavaScript_files_Learn_more_at_https_Colon_Slash_Slashaka_ms_Slashtsconfig: DiagnosticMessage;
+        Option_0_cannot_be_specified_without_specifying_option_1_or_option_2: DiagnosticMessage;
+        Option_resolveJsonModule_cannot_be_specified_without_node_module_resolution_strategy: DiagnosticMessage;
+        Generates_a_sourcemap_for_each_corresponding_d_ts_file: DiagnosticMessage;
+        Concatenate_and_emit_output_to_single_file: DiagnosticMessage;
+        Generates_corresponding_d_ts_file: DiagnosticMessage;
+        Specify_the_location_where_debugger_should_locate_map_files_instead_of_generated_locations: DiagnosticMessage;
+        Specify_the_location_where_debugger_should_locate_TypeScript_files_instead_of_source_locations: DiagnosticMessage;
+        Watch_input_files: DiagnosticMessage;
+        Redirect_output_structure_to_the_directory: DiagnosticMessage;
+        Do_not_erase_const_enum_declarations_in_generated_code: DiagnosticMessage;
+        Do_not_emit_outputs_if_any_errors_were_reported: DiagnosticMessage;
+        Do_not_emit_comments_to_output: DiagnosticMessage;
+        Do_not_emit_outputs: DiagnosticMessage;
+        Allow_default_imports_from_modules_with_no_default_export_This_does_not_affect_code_emit_just_typechecking: DiagnosticMessage;
+        Skip_type_checking_of_declaration_files: DiagnosticMessage;
+        Do_not_resolve_the_real_path_of_symlinks: DiagnosticMessage;
+        Only_emit_d_ts_declaration_files: DiagnosticMessage;
+        Specify_ECMAScript_target_version_Colon_ES3_default_ES5_ES2015_ES2016_ES2017_ES2018_or_ESNEXT: DiagnosticMessage;
+        Specify_module_code_generation_Colon_none_commonjs_amd_system_umd_es2015_or_ESNext: DiagnosticMessage;
+        Print_this_message: DiagnosticMessage;
+        Print_the_compiler_s_version: DiagnosticMessage;
+        Compile_the_project_given_the_path_to_its_configuration_file_or_to_a_folder_with_a_tsconfig_json: DiagnosticMessage;
+        Syntax_Colon_0: DiagnosticMessage;
+        options: DiagnosticMessage;
+        file: DiagnosticMessage;
+        Examples_Colon_0: DiagnosticMessage;
+        Options_Colon: DiagnosticMessage;
+        Version_0: DiagnosticMessage;
+        Insert_command_line_options_and_files_from_a_file: DiagnosticMessage;
+        Starting_compilation_in_watch_mode: DiagnosticMessage;
+        File_change_detected_Starting_incremental_compilation: DiagnosticMessage;
+        KIND: DiagnosticMessage;
+        FILE: DiagnosticMessage;
+        VERSION: DiagnosticMessage;
+        LOCATION: DiagnosticMessage;
+        DIRECTORY: DiagnosticMessage;
+        STRATEGY: DiagnosticMessage;
+        FILE_OR_DIRECTORY: DiagnosticMessage;
+        Generates_corresponding_map_file: DiagnosticMessage;
+        Compiler_option_0_expects_an_argument: DiagnosticMessage;
+        Unterminated_quoted_string_in_response_file_0: DiagnosticMessage;
+        Argument_for_0_option_must_be_Colon_1: DiagnosticMessage;
+        Locale_must_be_of_the_form_language_or_language_territory_For_example_0_or_1: DiagnosticMessage;
+        Unsupported_locale_0: DiagnosticMessage;
+        Unable_to_open_file_0: DiagnosticMessage;
+        Corrupted_locale_file_0: DiagnosticMessage;
+        Raise_error_on_expressions_and_declarations_with_an_implied_any_type: DiagnosticMessage;
+        File_0_not_found: DiagnosticMessage;
+        File_0_has_unsupported_extension_The_only_supported_extensions_are_1: DiagnosticMessage;
+        Suppress_noImplicitAny_errors_for_indexing_objects_lacking_index_signatures: DiagnosticMessage;
+        Do_not_emit_declarations_for_code_that_has_an_internal_annotation: DiagnosticMessage;
+        Specify_the_root_directory_of_input_files_Use_to_control_the_output_directory_structure_with_outDir: DiagnosticMessage;
+        File_0_is_not_under_rootDir_1_rootDir_is_expected_to_contain_all_source_files: DiagnosticMessage;
+        Specify_the_end_of_line_sequence_to_be_used_when_emitting_files_Colon_CRLF_dos_or_LF_unix: DiagnosticMessage;
+        NEWLINE: DiagnosticMessage;
+        Option_0_can_only_be_specified_in_tsconfig_json_file: DiagnosticMessage;
+        Enables_experimental_support_for_ES7_decorators: DiagnosticMessage;
+        Enables_experimental_support_for_emitting_type_metadata_for_decorators: DiagnosticMessage;
+        Enables_experimental_support_for_ES7_async_functions: DiagnosticMessage;
+        Specify_module_resolution_strategy_Colon_node_Node_js_or_classic_TypeScript_pre_1_6: DiagnosticMessage;
+        Initializes_a_TypeScript_project_and_creates_a_tsconfig_json_file: DiagnosticMessage;
+        Successfully_created_a_tsconfig_json_file: DiagnosticMessage;
+        Suppress_excess_property_checks_for_object_literals: DiagnosticMessage;
+        Stylize_errors_and_messages_using_color_and_context_experimental: DiagnosticMessage;
+        Do_not_report_errors_on_unused_labels: DiagnosticMessage;
+        Report_error_when_not_all_code_paths_in_function_return_a_value: DiagnosticMessage;
+        Report_errors_for_fallthrough_cases_in_switch_statement: DiagnosticMessage;
+        Do_not_report_errors_on_unreachable_code: DiagnosticMessage;
+        Disallow_inconsistently_cased_references_to_the_same_file: DiagnosticMessage;
+        Specify_library_files_to_be_included_in_the_compilation: DiagnosticMessage;
+        Specify_JSX_code_generation_Colon_preserve_react_native_or_react: DiagnosticMessage;
+        File_0_has_an_unsupported_extension_so_skipping_it: DiagnosticMessage;
+        Only_amd_and_system_modules_are_supported_alongside_0: DiagnosticMessage;
+        Base_directory_to_resolve_non_absolute_module_names: DiagnosticMessage;
+        Deprecated_Use_jsxFactory_instead_Specify_the_object_invoked_for_createElement_when_targeting_react_JSX_emit: DiagnosticMessage;
+        Enable_tracing_of_the_name_resolution_process: DiagnosticMessage;
+        Resolving_module_0_from_1: DiagnosticMessage;
+        Explicitly_specified_module_resolution_kind_Colon_0: DiagnosticMessage;
+        Module_resolution_kind_is_not_specified_using_0: DiagnosticMessage;
+        Module_name_0_was_successfully_resolved_to_1: DiagnosticMessage;
+        Module_name_0_was_not_resolved: DiagnosticMessage;
+        paths_option_is_specified_looking_for_a_pattern_to_match_module_name_0: DiagnosticMessage;
+        Module_name_0_matched_pattern_1: DiagnosticMessage;
+        Trying_substitution_0_candidate_module_location_Colon_1: DiagnosticMessage;
+        Resolving_module_name_0_relative_to_base_url_1_2: DiagnosticMessage;
+        Loading_module_as_file_Slash_folder_candidate_module_location_0_target_file_type_1: DiagnosticMessage;
+        File_0_does_not_exist: DiagnosticMessage;
+        File_0_exist_use_it_as_a_name_resolution_result: DiagnosticMessage;
+        Loading_module_0_from_node_modules_folder_target_file_type_1: DiagnosticMessage;
+        Found_package_json_at_0: DiagnosticMessage;
+        package_json_does_not_have_a_0_field: DiagnosticMessage;
+        package_json_has_0_field_1_that_references_2: DiagnosticMessage;
+        Allow_javascript_files_to_be_compiled: DiagnosticMessage;
+        Option_0_should_have_array_of_strings_as_a_value: DiagnosticMessage;
+        Checking_if_0_is_the_longest_matching_prefix_for_1_2: DiagnosticMessage;
+        Expected_type_of_0_field_in_package_json_to_be_string_got_1: DiagnosticMessage;
+        baseUrl_option_is_set_to_0_using_this_value_to_resolve_non_relative_module_name_1: DiagnosticMessage;
+        rootDirs_option_is_set_using_it_to_resolve_relative_module_name_0: DiagnosticMessage;
+        Longest_matching_prefix_for_0_is_1: DiagnosticMessage;
+        Loading_0_from_the_root_dir_1_candidate_location_2: DiagnosticMessage;
+        Trying_other_entries_in_rootDirs: DiagnosticMessage;
+        Module_resolution_using_rootDirs_has_failed: DiagnosticMessage;
+        Do_not_emit_use_strict_directives_in_module_output: DiagnosticMessage;
+        Enable_strict_null_checks: DiagnosticMessage;
+        Unknown_option_excludes_Did_you_mean_exclude: DiagnosticMessage;
+        Raise_error_on_this_expressions_with_an_implied_any_type: DiagnosticMessage;
+        Resolving_type_reference_directive_0_containing_file_1_root_directory_2: DiagnosticMessage;
+        Resolving_using_primary_search_paths: DiagnosticMessage;
+        Resolving_from_node_modules_folder: DiagnosticMessage;
+        Type_reference_directive_0_was_successfully_resolved_to_1_primary_Colon_2: DiagnosticMessage;
+        Type_reference_directive_0_was_not_resolved: DiagnosticMessage;
+        Resolving_with_primary_search_path_0: DiagnosticMessage;
+        Root_directory_cannot_be_determined_skipping_primary_search_paths: DiagnosticMessage;
+        Resolving_type_reference_directive_0_containing_file_1_root_directory_not_set: DiagnosticMessage;
+        Type_declaration_files_to_be_included_in_compilation: DiagnosticMessage;
+        Looking_up_in_node_modules_folder_initial_location_0: DiagnosticMessage;
+        Containing_file_is_not_specified_and_root_directory_cannot_be_determined_skipping_lookup_in_node_modules_folder: DiagnosticMessage;
+        Resolving_type_reference_directive_0_containing_file_not_set_root_directory_1: DiagnosticMessage;
+        Resolving_type_reference_directive_0_containing_file_not_set_root_directory_not_set: DiagnosticMessage;
+        Resolving_real_path_for_0_result_1: DiagnosticMessage;
+        Cannot_compile_modules_using_option_0_unless_the_module_flag_is_amd_or_system: DiagnosticMessage;
+        File_name_0_has_a_1_extension_stripping_it: DiagnosticMessage;
+        _0_is_declared_but_its_value_is_never_read: DiagnosticMessage;
+        Report_errors_on_unused_locals: DiagnosticMessage;
+        Report_errors_on_unused_parameters: DiagnosticMessage;
+        The_maximum_dependency_depth_to_search_under_node_modules_and_load_JavaScript_files: DiagnosticMessage;
+        Cannot_import_type_declaration_files_Consider_importing_0_instead_of_1: DiagnosticMessage;
+        Property_0_is_declared_but_its_value_is_never_read: DiagnosticMessage;
+        Import_emit_helpers_from_tslib: DiagnosticMessage;
+        Auto_discovery_for_typings_is_enabled_in_project_0_Running_extra_resolution_pass_for_module_1_using_cache_location_2: DiagnosticMessage;
+        Parse_in_strict_mode_and_emit_use_strict_for_each_source_file: DiagnosticMessage;
+        Module_0_was_resolved_to_1_but_jsx_is_not_set: DiagnosticMessage;
+        Module_0_was_resolved_as_locally_declared_ambient_module_in_file_1: DiagnosticMessage;
+        Module_0_was_resolved_as_ambient_module_declared_in_1_since_this_file_was_not_modified: DiagnosticMessage;
+        Specify_the_JSX_factory_function_to_use_when_targeting_react_JSX_emit_e_g_React_createElement_or_h: DiagnosticMessage;
+        Resolution_for_module_0_was_found_in_cache_from_location_1: DiagnosticMessage;
+        Directory_0_does_not_exist_skipping_all_lookups_in_it: DiagnosticMessage;
+        Show_diagnostic_information: DiagnosticMessage;
+        Show_verbose_diagnostic_information: DiagnosticMessage;
+        Emit_a_single_file_with_source_maps_instead_of_having_a_separate_file: DiagnosticMessage;
+        Emit_the_source_alongside_the_sourcemaps_within_a_single_file_requires_inlineSourceMap_or_sourceMap_to_be_set: DiagnosticMessage;
+        Transpile_each_file_as_a_separate_module_similar_to_ts_transpileModule: DiagnosticMessage;
+        Print_names_of_generated_files_part_of_the_compilation: DiagnosticMessage;
+        Print_names_of_files_part_of_the_compilation: DiagnosticMessage;
+        The_locale_used_when_displaying_messages_to_the_user_e_g_en_us: DiagnosticMessage;
+        Do_not_generate_custom_helper_functions_like_extends_in_compiled_output: DiagnosticMessage;
+        Do_not_include_the_default_library_file_lib_d_ts: DiagnosticMessage;
+        Do_not_add_triple_slash_references_or_imported_modules_to_the_list_of_compiled_files: DiagnosticMessage;
+        Deprecated_Use_skipLibCheck_instead_Skip_type_checking_of_default_library_declaration_files: DiagnosticMessage;
+        List_of_folders_to_include_type_definitions_from: DiagnosticMessage;
+        Disable_size_limitations_on_JavaScript_projects: DiagnosticMessage;
+        The_character_set_of_the_input_files: DiagnosticMessage;
+        Emit_a_UTF_8_Byte_Order_Mark_BOM_in_the_beginning_of_output_files: DiagnosticMessage;
+        Do_not_truncate_error_messages: DiagnosticMessage;
+        Output_directory_for_generated_declaration_files: DiagnosticMessage;
+        A_series_of_entries_which_re_map_imports_to_lookup_locations_relative_to_the_baseUrl: DiagnosticMessage;
+        List_of_root_folders_whose_combined_content_represents_the_structure_of_the_project_at_runtime: DiagnosticMessage;
+        Show_all_compiler_options: DiagnosticMessage;
+        Deprecated_Use_outFile_instead_Concatenate_and_emit_output_to_single_file: DiagnosticMessage;
+        Command_line_Options: DiagnosticMessage;
+        Basic_Options: DiagnosticMessage;
+        Strict_Type_Checking_Options: DiagnosticMessage;
+        Module_Resolution_Options: DiagnosticMessage;
+        Source_Map_Options: DiagnosticMessage;
+        Additional_Checks: DiagnosticMessage;
+        Experimental_Options: DiagnosticMessage;
+        Advanced_Options: DiagnosticMessage;
+        Provide_full_support_for_iterables_in_for_of_spread_and_destructuring_when_targeting_ES5_or_ES3: DiagnosticMessage;
+        Enable_all_strict_type_checking_options: DiagnosticMessage;
+        List_of_language_service_plugins: DiagnosticMessage;
+        Scoped_package_detected_looking_in_0: DiagnosticMessage;
+        Reusing_resolution_of_module_0_to_file_1_from_old_program: DiagnosticMessage;
+        Reusing_module_resolutions_originating_in_0_since_resolutions_are_unchanged_from_old_program: DiagnosticMessage;
+        Disable_strict_checking_of_generic_signatures_in_function_types: DiagnosticMessage;
+        Enable_strict_checking_of_function_types: DiagnosticMessage;
+        Enable_strict_checking_of_property_initialization_in_classes: DiagnosticMessage;
+        Numeric_separators_are_not_allowed_here: DiagnosticMessage;
+        Multiple_consecutive_numeric_separators_are_not_permitted: DiagnosticMessage;
+        Found_package_json_at_0_Package_ID_is_1: DiagnosticMessage;
+        Whether_to_keep_outdated_console_output_in_watch_mode_instead_of_clearing_the_screen: DiagnosticMessage;
+        All_imports_in_import_declaration_are_unused: DiagnosticMessage;
+        Found_1_error_Watching_for_file_changes: DiagnosticMessage;
+        Found_0_errors_Watching_for_file_changes: DiagnosticMessage;
+        Resolve_keyof_to_string_valued_property_names_only_no_numbers_or_symbols: DiagnosticMessage;
+        _0_is_declared_but_never_used: DiagnosticMessage;
+        Include_modules_imported_with_json_extension: DiagnosticMessage;
+        All_destructured_elements_are_unused: DiagnosticMessage;
+        All_variables_are_unused: DiagnosticMessage;
+        Projects_to_reference: DiagnosticMessage;
+        Enable_project_compilation: DiagnosticMessage;
+        Project_references_may_not_form_a_circular_graph_Cycle_detected_Colon_0: DiagnosticMessage;
+        Composite_projects_may_not_disable_declaration_emit: DiagnosticMessage;
+        Output_file_0_has_not_been_built_from_source_file_1: DiagnosticMessage;
+        Referenced_project_0_must_have_setting_composite_Colon_true: DiagnosticMessage;
+        File_0_is_not_in_project_file_list_Projects_must_list_all_files_or_use_an_include_pattern: DiagnosticMessage;
+        Cannot_prepend_project_0_because_it_does_not_have_outFile_set: DiagnosticMessage;
+        Output_file_0_from_project_1_does_not_exist: DiagnosticMessage;
+        Project_0_is_out_of_date_because_oldest_output_1_is_older_than_newest_input_2: DiagnosticMessage;
+        Project_0_is_up_to_date_because_newest_input_1_is_older_than_oldest_output_2: DiagnosticMessage;
+        Project_0_is_out_of_date_because_output_file_1_does_not_exist: DiagnosticMessage;
+        Project_0_is_out_of_date_because_its_dependency_1_is_out_of_date: DiagnosticMessage;
+        Project_0_is_up_to_date_with_d_ts_files_from_its_dependencies: DiagnosticMessage;
+        Projects_in_this_build_Colon_0: DiagnosticMessage;
+        A_non_dry_build_would_delete_the_following_files_Colon_0: DiagnosticMessage;
+        A_non_dry_build_would_build_project_0: DiagnosticMessage;
+        Building_project_0: DiagnosticMessage;
+        Updating_output_timestamps_of_project_0: DiagnosticMessage;
+        delete_this_Project_0_is_up_to_date_because_it_was_previously_built: DiagnosticMessage;
+        Project_0_is_up_to_date: DiagnosticMessage;
+        Skipping_build_of_project_0_because_its_dependency_1_has_errors: DiagnosticMessage;
+        Project_0_can_t_be_built_because_its_dependency_1_has_errors: DiagnosticMessage;
+        Build_one_or_more_projects_and_their_dependencies_if_out_of_date: DiagnosticMessage;
+        Delete_the_outputs_of_all_projects: DiagnosticMessage;
+        Enable_verbose_logging: DiagnosticMessage;
+        Show_what_would_be_built_or_deleted_if_specified_with_clean: DiagnosticMessage;
+        Build_all_projects_including_those_that_appear_to_be_up_to_date: DiagnosticMessage;
+        Option_build_must_be_the_first_command_line_argument: DiagnosticMessage;
+        Options_0_and_1_cannot_be_combined: DiagnosticMessage;
+        Skipping_clean_because_not_all_projects_could_be_located: DiagnosticMessage;
+        Variable_0_implicitly_has_an_1_type: DiagnosticMessage;
+        Parameter_0_implicitly_has_an_1_type: DiagnosticMessage;
+        Member_0_implicitly_has_an_1_type: DiagnosticMessage;
+        new_expression_whose_target_lacks_a_construct_signature_implicitly_has_an_any_type: DiagnosticMessage;
+        _0_which_lacks_return_type_annotation_implicitly_has_an_1_return_type: DiagnosticMessage;
+        Function_expression_which_lacks_return_type_annotation_implicitly_has_an_0_return_type: DiagnosticMessage;
+        Construct_signature_which_lacks_return_type_annotation_implicitly_has_an_any_return_type: DiagnosticMessage;
+        Element_implicitly_has_an_any_type_because_index_expression_is_not_of_type_number: DiagnosticMessage;
+        Could_not_find_a_declaration_file_for_module_0_1_implicitly_has_an_any_type: DiagnosticMessage;
+        Element_implicitly_has_an_any_type_because_type_0_has_no_index_signature: DiagnosticMessage;
+        Object_literal_s_property_0_implicitly_has_an_1_type: DiagnosticMessage;
+        Rest_parameter_0_implicitly_has_an_any_type: DiagnosticMessage;
+        Call_signature_which_lacks_return_type_annotation_implicitly_has_an_any_return_type: DiagnosticMessage;
+        _0_implicitly_has_type_any_because_it_does_not_have_a_type_annotation_and_is_referenced_directly_or_indirectly_in_its_own_initializer: DiagnosticMessage;
+        _0_implicitly_has_return_type_any_because_it_does_not_have_a_return_type_annotation_and_is_referenced_directly_or_indirectly_in_one_of_its_return_expressions: DiagnosticMessage;
+        Function_implicitly_has_return_type_any_because_it_does_not_have_a_return_type_annotation_and_is_referenced_directly_or_indirectly_in_one_of_its_return_expressions: DiagnosticMessage;
+        Generator_implicitly_has_type_0_because_it_does_not_yield_any_values_Consider_supplying_a_return_type: DiagnosticMessage;
+        JSX_element_implicitly_has_type_any_because_no_interface_JSX_0_exists: DiagnosticMessage;
+        Unreachable_code_detected: DiagnosticMessage;
+        Unused_label: DiagnosticMessage;
+        Fallthrough_case_in_switch: DiagnosticMessage;
+        Not_all_code_paths_return_a_value: DiagnosticMessage;
+        Binding_element_0_implicitly_has_an_1_type: DiagnosticMessage;
+        Property_0_implicitly_has_type_any_because_its_set_accessor_lacks_a_parameter_type_annotation: DiagnosticMessage;
+        Property_0_implicitly_has_type_any_because_its_get_accessor_lacks_a_return_type_annotation: DiagnosticMessage;
+        Variable_0_implicitly_has_type_1_in_some_locations_where_its_type_cannot_be_determined: DiagnosticMessage;
+        Try_npm_install_types_Slash_0_if_it_exists_or_add_a_new_declaration_d_ts_file_containing_declare_module_0: DiagnosticMessage;
+        Dynamic_import_s_specifier_must_be_of_type_string_but_here_has_type_0: DiagnosticMessage;
+        Enables_emit_interoperability_between_CommonJS_and_ES_Modules_via_creation_of_namespace_objects_for_all_imports_Implies_allowSyntheticDefaultImports: DiagnosticMessage;
+        A_namespace_style_import_cannot_be_called_or_constructed_and_will_cause_a_failure_at_runtime: DiagnosticMessage;
+        Mapped_object_type_implicitly_has_an_any_template_type: DiagnosticMessage;
+        You_cannot_rename_this_element: DiagnosticMessage;
+        You_cannot_rename_elements_that_are_defined_in_the_standard_TypeScript_library: DiagnosticMessage;
+        import_can_only_be_used_in_a_ts_file: DiagnosticMessage;
+        export_can_only_be_used_in_a_ts_file: DiagnosticMessage;
+        type_parameter_declarations_can_only_be_used_in_a_ts_file: DiagnosticMessage;
+        implements_clauses_can_only_be_used_in_a_ts_file: DiagnosticMessage;
+        interface_declarations_can_only_be_used_in_a_ts_file: DiagnosticMessage;
+        module_declarations_can_only_be_used_in_a_ts_file: DiagnosticMessage;
+        type_aliases_can_only_be_used_in_a_ts_file: DiagnosticMessage;
+        _0_can_only_be_used_in_a_ts_file: DiagnosticMessage;
+        types_can_only_be_used_in_a_ts_file: DiagnosticMessage;
+        type_arguments_can_only_be_used_in_a_ts_file: DiagnosticMessage;
+        parameter_modifiers_can_only_be_used_in_a_ts_file: DiagnosticMessage;
+        non_null_assertions_can_only_be_used_in_a_ts_file: DiagnosticMessage;
+        enum_declarations_can_only_be_used_in_a_ts_file: DiagnosticMessage;
+        type_assertion_expressions_can_only_be_used_in_a_ts_file: DiagnosticMessage;
+        Octal_literal_types_must_use_ES2015_syntax_Use_the_syntax_0: DiagnosticMessage;
+        Octal_literals_are_not_allowed_in_enums_members_initializer_Use_the_syntax_0: DiagnosticMessage;
+        Report_errors_in_js_files: DiagnosticMessage;
+        JSDoc_types_can_only_be_used_inside_documentation_comments: DiagnosticMessage;
+        JSDoc_typedef_tag_should_either_have_a_type_annotation_or_be_followed_by_property_or_member_tags: DiagnosticMessage;
+        JSDoc_0_is_not_attached_to_a_class: DiagnosticMessage;
+        JSDoc_0_1_does_not_match_the_extends_2_clause: DiagnosticMessage;
+        JSDoc_param_tag_has_name_0_but_there_is_no_parameter_with_that_name: DiagnosticMessage;
+        Class_declarations_cannot_have_more_than_one_augments_or_extends_tag: DiagnosticMessage;
+        Expected_0_type_arguments_provide_these_with_an_extends_tag: DiagnosticMessage;
+        Expected_0_1_type_arguments_provide_these_with_an_extends_tag: DiagnosticMessage;
+        JSDoc_may_only_appear_in_the_last_parameter_of_a_signature: DiagnosticMessage;
+        JSDoc_param_tag_has_name_0_but_there_is_no_parameter_with_that_name_It_would_match_arguments_if_it_had_an_array_type: DiagnosticMessage;
+        Only_identifiers_Slashqualified_names_with_optional_type_arguments_are_currently_supported_in_a_class_extends_clause: DiagnosticMessage;
+        class_expressions_are_not_currently_supported: DiagnosticMessage;
+        Language_service_is_disabled: DiagnosticMessage;
+        JSX_attributes_must_only_be_assigned_a_non_empty_expression: DiagnosticMessage;
+        JSX_elements_cannot_have_multiple_attributes_with_the_same_name: DiagnosticMessage;
+        Expected_corresponding_JSX_closing_tag_for_0: DiagnosticMessage;
+        JSX_attribute_expected: DiagnosticMessage;
+        Cannot_use_JSX_unless_the_jsx_flag_is_provided: DiagnosticMessage;
+        A_constructor_cannot_contain_a_super_call_when_its_class_extends_null: DiagnosticMessage;
+        An_unary_expression_with_the_0_operator_is_not_allowed_in_the_left_hand_side_of_an_exponentiation_expression_Consider_enclosing_the_expression_in_parentheses: DiagnosticMessage;
+        A_type_assertion_expression_is_not_allowed_in_the_left_hand_side_of_an_exponentiation_expression_Consider_enclosing_the_expression_in_parentheses: DiagnosticMessage;
+        JSX_element_0_has_no_corresponding_closing_tag: DiagnosticMessage;
+        super_must_be_called_before_accessing_this_in_the_constructor_of_a_derived_class: DiagnosticMessage;
+        Unknown_type_acquisition_option_0: DiagnosticMessage;
+        super_must_be_called_before_accessing_a_property_of_super_in_the_constructor_of_a_derived_class: DiagnosticMessage;
+        _0_is_not_a_valid_meta_property_for_keyword_1_Did_you_mean_2: DiagnosticMessage;
+        Meta_property_0_is_only_allowed_in_the_body_of_a_function_declaration_function_expression_or_constructor: DiagnosticMessage;
+        JSX_fragment_has_no_corresponding_closing_tag: DiagnosticMessage;
+        Expected_corresponding_closing_tag_for_JSX_fragment: DiagnosticMessage;
+        JSX_fragment_is_not_supported_when_using_jsxFactory: DiagnosticMessage;
+        JSX_fragment_is_not_supported_when_using_an_inline_JSX_factory_pragma: DiagnosticMessage;
+        Circularity_detected_while_resolving_configuration_Colon_0: DiagnosticMessage;
+        A_path_in_an_extends_option_must_be_relative_or_rooted_but_0_is_not: DiagnosticMessage;
+        The_files_list_in_config_file_0_is_empty: DiagnosticMessage;
+        No_inputs_were_found_in_config_file_0_Specified_include_paths_were_1_and_exclude_paths_were_2: DiagnosticMessage;
+        File_is_a_CommonJS_module_it_may_be_converted_to_an_ES6_module: DiagnosticMessage;
+        This_constructor_function_may_be_converted_to_a_class_declaration: DiagnosticMessage;
+        Import_may_be_converted_to_a_default_import: DiagnosticMessage;
+        JSDoc_types_may_be_moved_to_TypeScript_types: DiagnosticMessage;
+        require_call_may_be_converted_to_an_import: DiagnosticMessage;
+        Add_missing_super_call: DiagnosticMessage;
+        Make_super_call_the_first_statement_in_the_constructor: DiagnosticMessage;
+        Change_extends_to_implements: DiagnosticMessage;
+        Remove_declaration_for_Colon_0: DiagnosticMessage;
+        Remove_import_from_0: DiagnosticMessage;
+        Implement_interface_0: DiagnosticMessage;
+        Implement_inherited_abstract_class: DiagnosticMessage;
+        Add_0_to_unresolved_variable: DiagnosticMessage;
+        Remove_destructuring: DiagnosticMessage;
+        Remove_variable_statement: DiagnosticMessage;
+        Import_0_from_module_1: DiagnosticMessage;
+        Change_0_to_1: DiagnosticMessage;
+        Add_0_to_existing_import_declaration_from_1: DiagnosticMessage;
+        Declare_property_0: DiagnosticMessage;
+        Add_index_signature_for_property_0: DiagnosticMessage;
+        Disable_checking_for_this_file: DiagnosticMessage;
+        Ignore_this_error_message: DiagnosticMessage;
+        Initialize_property_0_in_the_constructor: DiagnosticMessage;
+        Initialize_static_property_0: DiagnosticMessage;
+        Change_spelling_to_0: DiagnosticMessage;
+        Declare_method_0: DiagnosticMessage;
+        Declare_static_method_0: DiagnosticMessage;
+        Prefix_0_with_an_underscore: DiagnosticMessage;
+        Rewrite_as_the_indexed_access_type_0: DiagnosticMessage;
+        Declare_static_property_0: DiagnosticMessage;
+        Call_decorator_expression: DiagnosticMessage;
+        Add_async_modifier_to_containing_function: DiagnosticMessage;
+        Convert_function_to_an_ES2015_class: DiagnosticMessage;
+        Convert_function_0_to_class: DiagnosticMessage;
+        Extract_to_0_in_1: DiagnosticMessage;
+        Extract_function: DiagnosticMessage;
+        Extract_constant: DiagnosticMessage;
+        Extract_to_0_in_enclosing_scope: DiagnosticMessage;
+        Extract_to_0_in_1_scope: DiagnosticMessage;
+        Annotate_with_type_from_JSDoc: DiagnosticMessage;
+        Annotate_with_types_from_JSDoc: DiagnosticMessage;
+        Infer_type_of_0_from_usage: DiagnosticMessage;
+        Infer_parameter_types_from_usage: DiagnosticMessage;
+        Convert_to_default_import: DiagnosticMessage;
+        Install_0: DiagnosticMessage;
+        Replace_import_with_0: DiagnosticMessage;
+        Use_synthetic_default_member: DiagnosticMessage;
+        Convert_to_ES6_module: DiagnosticMessage;
+        Add_undefined_type_to_property_0: DiagnosticMessage;
+        Add_initializer_to_property_0: DiagnosticMessage;
+        Add_definite_assignment_assertion_to_property_0: DiagnosticMessage;
+        Add_all_missing_members: DiagnosticMessage;
+        Infer_all_types_from_usage: DiagnosticMessage;
+        Delete_all_unused_declarations: DiagnosticMessage;
+        Prefix_all_unused_declarations_with_where_possible: DiagnosticMessage;
+        Fix_all_detected_spelling_errors: DiagnosticMessage;
+        Add_initializers_to_all_uninitialized_properties: DiagnosticMessage;
+        Add_definite_assignment_assertions_to_all_uninitialized_properties: DiagnosticMessage;
+        Add_undefined_type_to_all_uninitialized_properties: DiagnosticMessage;
+        Change_all_jsdoc_style_types_to_TypeScript: DiagnosticMessage;
+        Change_all_jsdoc_style_types_to_TypeScript_and_add_undefined_to_nullable_types: DiagnosticMessage;
+        Implement_all_unimplemented_interfaces: DiagnosticMessage;
+        Install_all_missing_types_packages: DiagnosticMessage;
+        Rewrite_all_as_indexed_access_types: DiagnosticMessage;
+        Convert_all_to_default_imports: DiagnosticMessage;
+        Make_all_super_calls_the_first_statement_in_their_constructor: DiagnosticMessage;
+        Add_qualifier_to_all_unresolved_variables_matching_a_member_name: DiagnosticMessage;
+        Change_all_extended_interfaces_to_implements: DiagnosticMessage;
+        Add_all_missing_super_calls: DiagnosticMessage;
+        Implement_all_inherited_abstract_classes: DiagnosticMessage;
+        Add_all_missing_async_modifiers: DiagnosticMessage;
+        Add_ts_ignore_to_all_error_messages: DiagnosticMessage;
+        Annotate_everything_with_types_from_JSDoc: DiagnosticMessage;
+        Add_to_all_uncalled_decorators: DiagnosticMessage;
+        Convert_all_constructor_functions_to_classes: DiagnosticMessage;
+        Generate_get_and_set_accessors: DiagnosticMessage;
+        Convert_require_to_import: DiagnosticMessage;
+        Convert_all_require_to_import: DiagnosticMessage;
+        Move_to_a_new_file: DiagnosticMessage;
+        Remove_unreachable_code: DiagnosticMessage;
+        Remove_all_unreachable_code: DiagnosticMessage;
+        Add_missing_typeof: DiagnosticMessage;
+        Remove_unused_label: DiagnosticMessage;
+        Remove_all_unused_labels: DiagnosticMessage;
+        Convert_0_to_mapped_object_type: DiagnosticMessage;
+        Convert_namespace_import_to_named_imports: DiagnosticMessage;
+        Convert_named_imports_to_namespace_import: DiagnosticMessage;
+        Add_or_remove_braces_in_an_arrow_function: DiagnosticMessage;
+        Add_braces_to_arrow_function: DiagnosticMessage;
+        Remove_braces_from_arrow_function: DiagnosticMessage;
+    };
+}
 declare namespace ts {
     type ErrorCallback = (message: DiagnosticMessage, length: number) => void;
+    function tokenIsIdentifierOrKeyword(token: SyntaxKind): boolean;
+    function tokenIsIdentifierOrKeywordOrGreaterThan(token: SyntaxKind): boolean;
     interface Scanner {
         getStartPos(): number;
         getToken(): SyntaxKind;
@@ -3058,6 +5918,7 @@ declare namespace ts {
         isIdentifier(): boolean;
         isReservedWord(): boolean;
         isUnterminated(): boolean;
+        getTokenFlags(): TokenFlags;
         reScanGreaterToken(): SyntaxKind;
         reScanSlashToken(): SyntaxKind;
         reScanTemplateToken(): SyntaxKind;
@@ -3077,14 +5938,25 @@ declare namespace ts {
         scanRange<T>(start: number, length: number, callback: () => T): T;
         tryScan<T>(callback: () => T): T;
     }
+    function isUnicodeIdentifierStart(code: number, languageVersion: ScriptTarget | undefined): boolean;
     function tokenToString(t: SyntaxKind): string | undefined;
+    function stringToToken(s: string): SyntaxKind | undefined;
+    function computeLineStarts(text: string): number[];
     function getPositionOfLineAndCharacter(sourceFile: SourceFileLike, line: number, character: number): number;
+    function computePositionOfLineAndCharacter(lineStarts: ReadonlyArray<number>, line: number, character: number, debugText?: string): number;
+    function getLineStarts(sourceFile: SourceFileLike): ReadonlyArray<number>;
+    /**
+     * We assume the first line starts at position 0 and 'position' is non-negative.
+     */
+    function computeLineAndCharacterOfPosition(lineStarts: ReadonlyArray<number>, position: number): LineAndCharacter;
     function getLineAndCharacterOfPosition(sourceFile: SourceFileLike, position: number): LineAndCharacter;
     function isWhiteSpaceLike(ch: number): boolean;
     /** Does not include line breaks. For that, see isWhiteSpaceLike. */
     function isWhiteSpaceSingleLine(ch: number): boolean;
     function isLineBreak(ch: number): boolean;
+    function isOctalDigit(ch: number): boolean;
     function couldStartTrivia(text: string, pos: number): boolean;
+    function skipTrivia(text: string, pos: number, stopAfterLineBreak?: boolean, stopAtComments?: boolean): number;
     function forEachLeadingCommentRange<U>(text: string, pos: number, cb: (pos: number, end: number, kind: CommentKind, hasTrailingNewLine: boolean) => U): U | undefined;
     function forEachLeadingCommentRange<T, U>(text: string, pos: number, cb: (pos: number, end: number, kind: CommentKind, hasTrailingNewLine: boolean, state: T) => U, state: T): U | undefined;
     function forEachTrailingCommentRange<U>(text: string, pos: number, cb: (pos: number, end: number, kind: CommentKind, hasTrailingNewLine: boolean) => U): U | undefined;
@@ -3097,8 +5969,628 @@ declare namespace ts {
     function getShebang(text: string): string | undefined;
     function isIdentifierStart(ch: number, languageVersion: ScriptTarget | undefined): boolean;
     function isIdentifierPart(ch: number, languageVersion: ScriptTarget | undefined): boolean;
+    function isIdentifierText(name: string, languageVersion: ScriptTarget | undefined): boolean;
     function createScanner(languageVersion: ScriptTarget, skipTrivia: boolean, languageVariant?: LanguageVariant, textInitial?: string, onError?: ErrorCallback, start?: number, length?: number): Scanner;
 }
+/** Non-internal stuff goes here */
+declare namespace ts {
+    function isExternalModuleNameRelative(moduleName: string): boolean;
+    function sortAndDeduplicateDiagnostics<T extends Diagnostic>(diagnostics: ReadonlyArray<T>): T[];
+}
+declare namespace ts {
+    const emptyArray: never[];
+    const resolvingEmptyArray: never[];
+    const emptyMap: ReadonlyMap<never>;
+    const emptyUnderscoreEscapedMap: ReadonlyUnderscoreEscapedMap<never>;
+    const externalHelpersModuleNameText = "tslib";
+    function getDeclarationOfKind<T extends Declaration>(symbol: Symbol, kind: T["kind"]): T | undefined;
+    /** Create a new escaped identifier map. */
+    function createUnderscoreEscapedMap<T>(): UnderscoreEscapedMap<T>;
+    function hasEntries(map: ReadonlyUnderscoreEscapedMap<any> | undefined): map is ReadonlyUnderscoreEscapedMap<any>;
+    function createSymbolTable(symbols?: ReadonlyArray<Symbol>): SymbolTable;
+    function toPath(fileName: string, basePath: string | undefined, getCanonicalFileName: (path: string) => string): Path;
+    function changesAffectModuleResolution(oldOptions: CompilerOptions, newOptions: CompilerOptions): boolean;
+    /**
+     * Iterates through the parent chain of a node and performs the callback on each parent until the callback
+     * returns a truthy value, then returns that value.
+     * If no such value is found, it applies the callback until the parent pointer is undefined or the callback returns "quit"
+     * At that point findAncestor returns undefined.
+     */
+    function findAncestor<T extends Node>(node: Node | undefined, callback: (element: Node) => element is T): T | undefined;
+    function findAncestor(node: Node | undefined, callback: (element: Node) => boolean | "quit"): Node | undefined;
+    /**
+     * Calls `callback` for each entry in the map, returning the first truthy result.
+     * Use `map.forEach` instead for normal iteration.
+     */
+    function forEachEntry<T, U>(map: ReadonlyUnderscoreEscapedMap<T>, callback: (value: T, key: __String) => U | undefined): U | undefined;
+    function forEachEntry<T, U>(map: ReadonlyMap<T>, callback: (value: T, key: string) => U | undefined): U | undefined;
+    /** `forEachEntry` for just keys. */
+    function forEachKey<T>(map: ReadonlyUnderscoreEscapedMap<{}>, callback: (key: __String) => T | undefined): T | undefined;
+    function forEachKey<T>(map: ReadonlyMap<{}>, callback: (key: string) => T | undefined): T | undefined;
+    /** Copy entries from `source` to `target`. */
+    function copyEntries<T>(source: ReadonlyUnderscoreEscapedMap<T>, target: UnderscoreEscapedMap<T>): void;
+    function copyEntries<T>(source: ReadonlyMap<T>, target: Map<T>): void;
+    /**
+     * Creates a set from the elements of an array.
+     *
+     * @param array the array of input elements.
+     */
+    function arrayToSet(array: ReadonlyArray<string>): Map<true>;
+    function arrayToSet<T>(array: ReadonlyArray<T>, makeKey: (value: T) => string | undefined): Map<true>;
+    function arrayToSet<T>(array: ReadonlyArray<T>, makeKey: (value: T) => __String | undefined): UnderscoreEscapedMap<true>;
+    function cloneMap(map: SymbolTable): SymbolTable;
+    function cloneMap<T>(map: ReadonlyMap<T>): Map<T>;
+    function cloneMap<T>(map: ReadonlyUnderscoreEscapedMap<T>): UnderscoreEscapedMap<T>;
+    function usingSingleLineStringWriter(action: (writer: EmitTextWriter) => void): string;
+    function getFullWidth(node: Node): number;
+    function getResolvedModule(sourceFile: SourceFile, moduleNameText: string): ResolvedModuleFull | undefined;
+    function setResolvedModule(sourceFile: SourceFile, moduleNameText: string, resolvedModule: ResolvedModuleFull): void;
+    function setResolvedTypeReferenceDirective(sourceFile: SourceFile, typeReferenceDirectiveName: string, resolvedTypeReferenceDirective: ResolvedTypeReferenceDirective): void;
+    function moduleResolutionIsEqualTo(oldResolution: ResolvedModuleFull, newResolution: ResolvedModuleFull): boolean;
+    function packageIdToString({ name, subModuleName, version }: PackageId): string;
+    function typeDirectiveIsEqualTo(oldResolution: ResolvedTypeReferenceDirective, newResolution: ResolvedTypeReferenceDirective): boolean;
+    function hasChangesInResolutions<T>(names: ReadonlyArray<string>, newResolutions: ReadonlyArray<T>, oldResolutions: ReadonlyMap<T> | undefined, comparer: (oldResolution: T, newResolution: T) => boolean): boolean;
+    function containsParseError(node: Node): boolean;
+    function getSourceFileOfNode(node: Node): SourceFile;
+    function getSourceFileOfNode(node: Node | undefined): SourceFile | undefined;
+    function isStatementWithLocals(node: Node): boolean;
+    function getStartPositionOfLine(line: number, sourceFile: SourceFileLike): number;
+    function nodePosToString(node: Node): string;
+    function getEndLinePosition(line: number, sourceFile: SourceFileLike): number;
+    /**
+     * Returns a value indicating whether a name is unique globally or within the current file.
+     * Note: This does not consider whether a name appears as a free identifier or not, so at the expression `x.y` this includes both `x` and `y`.
+     */
+    function isFileLevelUniqueName(sourceFile: SourceFile, name: string, hasGlobalName?: PrintHandlers["hasGlobalName"]): boolean;
+    function nodeIsMissing(node: Node | undefined): boolean;
+    function nodeIsPresent(node: Node | undefined): boolean;
+    /**
+     * Appends a range of value to begin of an array, returning the array.
+     *
+     * @param to The array to which `value` is to be appended. If `to` is `undefined`, a new array
+     * is created if `value` was appended.
+     * @param from The values to append to the array. If `from` is `undefined`, nothing is
+     * appended. If an element of `from` is `undefined`, that element is not appended.
+     */
+    function prependStatements<T extends Statement>(to: T[], from: ReadonlyArray<T> | undefined): T[] | undefined;
+    /**
+     * Determine if the given comment is a triple-slash
+     *
+     * @return true if the comment is a triple-slash comment else false
+     */
+    function isRecognizedTripleSlashComment(text: string, commentPos: number, commentEnd: number): boolean;
+    function isPinnedComment(text: string, start: number): boolean;
+    function getTokenPosOfNode(node: Node, sourceFile?: SourceFileLike, includeJsDoc?: boolean): number;
+    function getNonDecoratorTokenPosOfNode(node: Node, sourceFile?: SourceFileLike): number;
+    function getSourceTextOfNodeFromSourceFile(sourceFile: SourceFile, node: Node, includeTrivia?: boolean): string;
+    function getTextOfNodeFromSourceText(sourceText: string, node: Node, includeTrivia?: boolean): string;
+    function getTextOfNode(node: Node, includeTrivia?: boolean): string;
+    /**
+     * Note: it is expected that the `nodeArray` and the `node` are within the same file.
+     * For example, searching for a `SourceFile` in a `SourceFile[]` wouldn't work.
+     */
+    function indexOfNode(nodeArray: ReadonlyArray<Node>, node: Node): number;
+    /**
+     * Gets flags that control emit behavior of a node.
+     */
+    function getEmitFlags(node: Node): EmitFlags;
+    function getLiteralText(node: LiteralLikeNode, sourceFile: SourceFile): string;
+    function getTextOfConstantValue(value: string | number): string;
+    function escapeLeadingUnderscores(identifier: string): __String;
+    /**
+     * @deprecated Use `id.escapedText` to get the escaped text of an Identifier.
+     * @param identifier The identifier to escape
+     */
+    function escapeIdentifier(identifier: string): string;
+    function makeIdentifierFromModuleName(moduleName: string): string;
+    function isBlockOrCatchScoped(declaration: Declaration): boolean;
+    function isCatchClauseVariableDeclarationOrBindingElement(declaration: Declaration): boolean;
+    function isAmbientModule(node: Node): node is AmbientModuleDeclaration;
+    function isModuleWithStringLiteralName(node: Node): node is ModuleDeclaration;
+    function isNonGlobalAmbientModule(node: Node): node is ModuleDeclaration & {
+        name: StringLiteral;
+    };
+    /**
+     * An effective module (namespace) declaration is either
+     * 1. An actual declaration: namespace X { ... }
+     * 2. A Javascript declaration, which is:
+     *    An identifier in a nested property access expression: Y in `X.Y.Z = { ... }`
+     */
+    function isEffectiveModuleDeclaration(node: Node): boolean;
+    /** Given a symbol for a module, checks that it is a shorthand ambient module. */
+    function isShorthandAmbientModuleSymbol(moduleSymbol: Symbol): boolean;
+    function isBlockScopedContainerTopLevel(node: Node): boolean;
+    function isGlobalScopeAugmentation(module: ModuleDeclaration): boolean;
+    function isExternalModuleAugmentation(node: Node): node is AmbientModuleDeclaration;
+    function isModuleAugmentationExternal(node: AmbientModuleDeclaration): boolean;
+    function isEffectiveExternalModule(node: SourceFile, compilerOptions: CompilerOptions): boolean;
+    function isBlockScope(node: Node, parentNode: Node): boolean;
+    function isDeclarationWithTypeParameters(node: Node): node is DeclarationWithTypeParameters;
+    function isAnyImportSyntax(node: Node): node is AnyImportSyntax;
+    function isLateVisibilityPaintedStatement(node: Node): node is LateVisibilityPaintedStatement;
+    function isAnyImportOrReExport(node: Node): node is AnyImportOrReExport;
+    function getEnclosingBlockScopeContainer(node: Node): Node;
+    function declarationNameToString(name: DeclarationName | QualifiedName): string;
+    function getNameFromIndexInfo(info: IndexInfo): string | undefined;
+    function getTextOfPropertyName(name: PropertyName): __String;
+    function entityNameToString(name: EntityNameOrEntityNameExpression): string;
+    function createDiagnosticForNode(node: Node, message: DiagnosticMessage, arg0?: string | number, arg1?: string | number, arg2?: string | number, arg3?: string | number): DiagnosticWithLocation;
+    function createDiagnosticForNodeArray(sourceFile: SourceFile, nodes: NodeArray<Node>, message: DiagnosticMessage, arg0?: string | number, arg1?: string | number, arg2?: string | number, arg3?: string | number): Diagnostic;
+    function createDiagnosticForNodeInSourceFile(sourceFile: SourceFile, node: Node, message: DiagnosticMessage, arg0?: string | number, arg1?: string | number, arg2?: string | number, arg3?: string | number): DiagnosticWithLocation;
+    function createDiagnosticForNodeFromMessageChain(node: Node, messageChain: DiagnosticMessageChain): DiagnosticWithLocation;
+    function getSpanOfTokenAtPosition(sourceFile: SourceFile, pos: number): TextSpan;
+    function getErrorSpanForNode(sourceFile: SourceFile, node: Node): TextSpan;
+    function isExternalOrCommonJsModule(file: SourceFile): boolean;
+    function isJsonSourceFile(file: SourceFile): file is JsonSourceFile;
+    function isConstEnumDeclaration(node: Node): boolean;
+    function isConst(node: Node): boolean;
+    function isLet(node: Node): boolean;
+    function isSuperCall(n: Node): n is SuperCall;
+    function isImportCall(n: Node): n is ImportCall;
+    function isLiteralImportTypeNode(n: Node): n is LiteralImportTypeNode;
+    function isPrologueDirective(node: Node): node is PrologueDirective;
+    function getLeadingCommentRangesOfNode(node: Node, sourceFileOfNode: SourceFile): CommentRange[] | undefined;
+    function getJSDocCommentRanges(node: Node, text: string): CommentRange[] | undefined;
+    const fullTripleSlashReferencePathRegEx: RegExp;
+    const fullTripleSlashAMDReferencePathRegEx: RegExp;
+    function isPartOfTypeNode(node: Node): boolean;
+    function isChildOfNodeWithKind(node: Node, kind: SyntaxKind): boolean;
+    function forEachReturnStatement<T>(body: Block, visitor: (stmt: ReturnStatement) => T): T | undefined;
+    function forEachYieldExpression(body: Block, visitor: (expr: YieldExpression) => void): void;
+    /**
+     * Gets the most likely element type for a TypeNode. This is not an exhaustive test
+     * as it assumes a rest argument can only be an array type (either T[], or Array<T>).
+     *
+     * @param node The type node.
+     */
+    function getRestParameterElementType(node: TypeNode | undefined): TypeNode | undefined;
+    function getMembersOfDeclaration(node: Declaration): NodeArray<ClassElement | TypeElement | ObjectLiteralElement> | undefined;
+    function isVariableLike(node: Node): node is VariableLikeDeclaration;
+    function isVariableLikeOrAccessor(node: Node): node is AccessorDeclaration | VariableLikeDeclaration;
+    function isVariableDeclarationInVariableStatement(node: VariableDeclaration): boolean;
+    function isValidESSymbolDeclaration(node: Node): node is VariableDeclaration | PropertyDeclaration | SignatureDeclaration;
+    function introducesArgumentsExoticObject(node: Node): boolean;
+    function unwrapInnermostStatementOfLabel(node: LabeledStatement, beforeUnwrapLabelCallback?: (node: LabeledStatement) => void): Statement;
+    function isFunctionBlock(node: Node): boolean;
+    function isObjectLiteralMethod(node: Node): node is MethodDeclaration;
+    function isObjectLiteralOrClassExpressionMethod(node: Node): node is MethodDeclaration;
+    function isIdentifierTypePredicate(predicate: TypePredicate): predicate is IdentifierTypePredicate;
+    function isThisTypePredicate(predicate: TypePredicate): predicate is ThisTypePredicate;
+    function getPropertyAssignment(objectLiteral: ObjectLiteralExpression, key: string, key2?: string): ReadonlyArray<PropertyAssignment>;
+    function getTsConfigObjectLiteralExpression(tsConfigSourceFile: TsConfigSourceFile | undefined): ObjectLiteralExpression | undefined;
+    function getTsConfigPropArrayElementValue(tsConfigSourceFile: TsConfigSourceFile | undefined, propKey: string, elementValue: string): StringLiteral | undefined;
+    function getTsConfigPropArray(tsConfigSourceFile: TsConfigSourceFile | undefined, propKey: string): ReadonlyArray<PropertyAssignment>;
+    function getContainingFunction(node: Node): SignatureDeclaration | undefined;
+    function getContainingClass(node: Node): ClassLikeDeclaration | undefined;
+    function getThisContainer(node: Node, includeArrowFunctions: boolean): Node;
+    function getNewTargetContainer(node: Node): Node | undefined;
+    /**
+     * Given an super call/property node, returns the closest node where
+     * - a super call/property access is legal in the node and not legal in the parent node the node.
+     *   i.e. super call is legal in constructor but not legal in the class body.
+     * - the container is an arrow function (so caller might need to call getSuperContainer again in case it needs to climb higher)
+     * - a super call/property is definitely illegal in the container (but might be legal in some subnode)
+     *   i.e. super property access is illegal in function declaration but can be legal in the statement list
+     */
+    function getSuperContainer(node: Node, stopOnFunctions: boolean): Node;
+    function getImmediatelyInvokedFunctionExpression(func: Node): CallExpression | undefined;
+    /**
+     * Determines whether a node is a property or element access expression for `super`.
+     */
+    function isSuperProperty(node: Node): node is SuperProperty;
+    /**
+     * Determines whether a node is a property or element access expression for `this`.
+     */
+    function isThisProperty(node: Node): boolean;
+    function getEntityNameFromTypeNode(node: TypeNode): EntityNameOrEntityNameExpression | undefined;
+    function getInvokedExpression(node: CallLikeExpression): Expression;
+    function nodeCanBeDecorated(node: ClassDeclaration): true;
+    function nodeCanBeDecorated(node: ClassElement, parent: Node): boolean;
+    function nodeCanBeDecorated(node: Node, parent: Node, grandparent: Node): boolean;
+    function nodeIsDecorated(node: ClassDeclaration): boolean;
+    function nodeIsDecorated(node: ClassElement, parent: Node): boolean;
+    function nodeIsDecorated(node: Node, parent: Node, grandparent: Node): boolean;
+    function nodeOrChildIsDecorated(node: ClassDeclaration): boolean;
+    function nodeOrChildIsDecorated(node: ClassElement, parent: Node): boolean;
+    function nodeOrChildIsDecorated(node: Node, parent: Node, grandparent: Node): boolean;
+    function childIsDecorated(node: ClassDeclaration): boolean;
+    function childIsDecorated(node: Node, parent: Node): boolean;
+    function isJSXTagName(node: Node): boolean;
+    function isExpressionNode(node: Node): boolean;
+    function isInExpressionContext(node: Node): boolean;
+    function isExternalModuleImportEqualsDeclaration(node: Node): boolean;
+    function getExternalModuleImportEqualsDeclarationExpression(node: Node): Expression;
+    function isInternalModuleImportEqualsDeclaration(node: Node): node is ImportEqualsDeclaration;
+    function isSourceFileJavaScript(file: SourceFile): boolean;
+    function isSourceFileNotJavaScript(file: SourceFile): boolean;
+    function isInJavaScriptFile(node: Node | undefined): boolean;
+    function isInJsonFile(node: Node | undefined): boolean;
+    function isInJSDoc(node: Node | undefined): boolean;
+    function isJSDocIndexSignature(node: TypeReferenceNode | ExpressionWithTypeArguments): boolean | undefined;
+    /**
+     * Returns true if the node is a CallExpression to the identifier 'require' with
+     * exactly one argument (of the form 'require("name")').
+     * This function does not test if the node is in a JavaScript file or not.
+     */
+    function isRequireCall(callExpression: Node, checkArgumentIsStringLiteralLike: true): callExpression is RequireOrImportCall & {
+        expression: Identifier;
+        arguments: [StringLiteralLike];
+    };
+    function isRequireCall(callExpression: Node, checkArgumentIsStringLiteralLike: boolean): callExpression is CallExpression;
+    function isSingleOrDoubleQuote(charCode: number): boolean;
+    function isStringDoubleQuoted(str: StringLiteralLike, sourceFile: SourceFile): boolean;
+    function getDeclarationOfJSInitializer(node: Node): Node | undefined;
+    /** Get the initializer, taking into account defaulted Javascript initializers */
+    function getEffectiveInitializer(node: HasExpressionInitializer): Expression | undefined;
+    /**
+     * Get the assignment 'initializer' -- the righthand side-- when the initializer is container-like (See getJavascriptInitializer).
+     * We treat the right hand side of assignments with container-like initalizers as declarations.
+     */
+    function getAssignedJavascriptInitializer(node: Node): Expression | undefined;
+    /**
+     * Recognized Javascript container-like initializers are:
+     * 1. (function() {})() -- IIFEs
+     * 2. function() { } -- Function expressions
+     * 3. class { } -- Class expressions
+     * 4. {} -- Empty object literals
+     * 5. { ... } -- Non-empty object literals, when used to initialize a prototype, like `C.prototype = { m() { } }`
+     *
+     * This function returns the provided initializer, or undefined if it is not valid.
+     */
+    function getJavascriptInitializer(initializer: Node, isPrototypeAssignment: boolean): Expression | undefined;
+    function isDefaultedJavascriptInitializer(node: BinaryExpression): boolean | undefined;
+    /** Given a Javascript initializer, return the outer name. That is, the lhs of the assignment or the declaration name. */
+    function getOuterNameOfJsInitializer(node: Declaration): DeclarationName | undefined;
+    function getRightMostAssignedExpression(node: Expression): Expression;
+    function isExportsIdentifier(node: Node): boolean;
+    function isModuleExportsPropertyAccessExpression(node: Node): boolean;
+    function getSpecialPropertyAssignmentKind(expr: BinaryExpression): SpecialPropertyAssignmentKind;
+    function getInitializerOfBinaryExpression(expr: BinaryExpression): Expression;
+    function isPrototypePropertyAssignment(node: Node): boolean;
+    function isSpecialPropertyDeclaration(expr: PropertyAccessExpression): boolean;
+    function importFromModuleSpecifier(node: StringLiteralLike): AnyValidImportOrReExport;
+    function tryGetImportFromModuleSpecifier(node: StringLiteralLike): AnyValidImportOrReExport | undefined;
+    function getExternalModuleName(node: AnyImportOrReExport | ImportTypeNode): Expression | undefined;
+    function getNamespaceDeclarationNode(node: ImportDeclaration | ImportEqualsDeclaration | ExportDeclaration): ImportEqualsDeclaration | NamespaceImport | undefined;
+    function isDefaultImport(node: ImportDeclaration | ImportEqualsDeclaration | ExportDeclaration): boolean;
+    function hasQuestionToken(node: Node): boolean;
+    function isJSDocConstructSignature(node: Node): boolean;
+    function isJSDocTypeAlias(node: Node): node is JSDocTypedefTag | JSDocCallbackTag;
+    function isTypeAlias(node: Node): node is JSDocTypedefTag | JSDocCallbackTag | TypeAliasDeclaration;
+    function getJSDocCommentsAndTags(hostNode: Node): ReadonlyArray<JSDoc | JSDocTag>;
+    /** Does the opposite of `getJSDocParameterTags`: given a JSDoc parameter, finds the parameter corresponding to it. */
+    function getParameterSymbolFromJSDoc(node: JSDocParameterTag): Symbol | undefined;
+    function getHostSignatureFromJSDoc(node: Node): SignatureDeclaration | undefined;
+    function getHostSignatureFromJSDocHost(host: HasJSDoc): SignatureDeclaration | undefined;
+    function getJSDocHost(node: Node): HasJSDoc;
+    function getTypeParameterFromJsDoc(node: TypeParameterDeclaration & {
+        parent: JSDocTemplateTag;
+    }): TypeParameterDeclaration | undefined;
+    function hasRestParameter(s: SignatureDeclaration | JSDocSignature): boolean;
+    function isRestParameter(node: ParameterDeclaration | JSDocParameterTag): boolean;
+    enum AssignmentKind {
+        None = 0,
+        Definite = 1,
+        Compound = 2
+    }
+    function getAssignmentTargetKind(node: Node): AssignmentKind;
+    function isAssignmentTarget(node: Node): boolean;
+    type NodeWithPossibleHoistedDeclaration = Block | VariableStatement | WithStatement | IfStatement | SwitchStatement | CaseBlock | CaseClause | DefaultClause | LabeledStatement | ForStatement | ForInStatement | ForOfStatement | DoStatement | WhileStatement | TryStatement | CatchClause;
+    /**
+     * Indicates whether a node could contain a `var` VariableDeclarationList that contributes to
+     * the same `var` declaration scope as the node's parent.
+     */
+    function isNodeWithPossibleHoistedDeclaration(node: Node): node is NodeWithPossibleHoistedDeclaration;
+    type ValueSignatureDeclaration = FunctionDeclaration | MethodDeclaration | ConstructorDeclaration | AccessorDeclaration | FunctionExpression | ArrowFunction;
+    function isValueSignatureDeclaration(node: Node): node is ValueSignatureDeclaration;
+    function walkUpParenthesizedTypes(node: Node): Node;
+    function walkUpParenthesizedExpressions(node: Node): Node;
+    function skipParentheses(node: Expression): Expression;
+    function skipParentheses(node: Node): Node;
+    function isDeleteTarget(node: Node): boolean;
+    function isNodeDescendantOf(node: Node, ancestor: Node): boolean;
+    function isDeclarationName(name: Node): boolean;
+    function isAnyDeclarationName(name: Node): boolean;
+    function isLiteralComputedPropertyDeclarationName(node: Node): boolean;
+    function isIdentifierName(node: Identifier): boolean;
+    function isAliasSymbolDeclaration(node: Node): boolean;
+    function exportAssignmentIsAlias(node: ExportAssignment | BinaryExpression): boolean;
+    function getClassExtendsHeritageClauseElement(node: ClassLikeDeclaration | InterfaceDeclaration): ExpressionWithTypeArguments | undefined;
+    function getClassImplementsHeritageClauseElements(node: ClassLikeDeclaration): NodeArray<ExpressionWithTypeArguments> | undefined;
+    /** Returns the node in an `extends` or `implements` clause of a class or interface. */
+    function getAllSuperTypeNodes(node: Node): ReadonlyArray<TypeNode>;
+    function getInterfaceBaseTypeNodes(node: InterfaceDeclaration): NodeArray<ExpressionWithTypeArguments> | undefined;
+    function getHeritageClause(clauses: NodeArray<HeritageClause> | undefined, kind: SyntaxKind): HeritageClause | undefined;
+    function tryResolveScriptReference(host: ScriptReferenceHost, sourceFile: SourceFile, reference: FileReference): SourceFile | undefined;
+    function getAncestor(node: Node | undefined, kind: SyntaxKind): Node | undefined;
+    function isKeyword(token: SyntaxKind): boolean;
+    function isContextualKeyword(token: SyntaxKind): boolean;
+    function isNonContextualKeyword(token: SyntaxKind): boolean;
+    function isStringANonContextualKeyword(name: string): boolean;
+    type TriviaKind = SyntaxKind.SingleLineCommentTrivia | SyntaxKind.MultiLineCommentTrivia | SyntaxKind.NewLineTrivia | SyntaxKind.WhitespaceTrivia | SyntaxKind.ShebangTrivia | SyntaxKind.ConflictMarkerTrivia;
+    function isTrivia(token: SyntaxKind): token is TriviaKind;
+    enum FunctionFlags {
+        Normal = 0,
+        Generator = 1,
+        Async = 2,
+        Invalid = 4,
+        AsyncGenerator = 3
+    }
+    function getFunctionFlags(node: SignatureDeclaration | undefined): FunctionFlags;
+    function isAsyncFunction(node: Node): boolean;
+    function isStringOrNumericLiteral(node: Node): node is StringLiteral | NumericLiteral;
+    /**
+     * A declaration has a dynamic name if both of the following are true:
+     *   1. The declaration has a computed property name
+     *   2. The computed name is *not* expressed as Symbol.<name>, where name
+     *      is a property of the Symbol constructor that denotes a built in
+     *      Symbol.
+     */
+    function hasDynamicName(declaration: Declaration): declaration is DynamicNamedDeclaration;
+    function isDynamicName(name: DeclarationName): boolean;
+    /**
+     * Checks if the expression is of the form:
+     *    Symbol.name
+     * where Symbol is literally the word "Symbol", and name is any identifierName
+     */
+    function isWellKnownSymbolSyntactically(node: Expression): boolean;
+    function getPropertyNameForPropertyNameNode(name: DeclarationName): __String | undefined;
+    type PropertyNameLiteral = Identifier | StringLiteralLike | NumericLiteral;
+    function isPropertyNameLiteral(node: Node): node is PropertyNameLiteral;
+    function getTextOfIdentifierOrLiteral(node: PropertyNameLiteral): string;
+    function getEscapedTextOfIdentifierOrLiteral(node: PropertyNameLiteral): __String;
+    function getPropertyNameForKnownSymbolName(symbolName: string): __String;
+    function isKnownSymbol(symbol: Symbol): boolean;
+    /**
+     * Includes the word "Symbol" with unicode escapes
+     */
+    function isESSymbolIdentifier(node: Node): boolean;
+    function isPushOrUnshiftIdentifier(node: Identifier): boolean;
+    function isParameterDeclaration(node: VariableLikeDeclaration): boolean;
+    function getRootDeclaration(node: Node): Node;
+    function nodeStartsNewLexicalEnvironment(node: Node): boolean;
+    function nodeIsSynthesized(range: TextRange): boolean;
+    function getOriginalSourceFile(sourceFile: SourceFile): SourceFile;
+    enum Associativity {
+        Left = 0,
+        Right = 1
+    }
+    function getExpressionAssociativity(expression: Expression): Associativity;
+    function getOperatorAssociativity(kind: SyntaxKind, operator: SyntaxKind, hasArguments?: boolean): Associativity;
+    function getExpressionPrecedence(expression: Expression): number;
+    function getOperator(expression: Expression): SyntaxKind.Unknown | SyntaxKind.EndOfFileToken | SyntaxKind.SingleLineCommentTrivia | SyntaxKind.MultiLineCommentTrivia | SyntaxKind.NewLineTrivia | SyntaxKind.WhitespaceTrivia | SyntaxKind.ShebangTrivia | SyntaxKind.ConflictMarkerTrivia | SyntaxKind.NumericLiteral | SyntaxKind.StringLiteral | SyntaxKind.JsxText | SyntaxKind.JsxTextAllWhiteSpaces | SyntaxKind.RegularExpressionLiteral | SyntaxKind.NoSubstitutionTemplateLiteral | SyntaxKind.TemplateHead | SyntaxKind.TemplateMiddle | SyntaxKind.TemplateTail | SyntaxKind.OpenBraceToken | SyntaxKind.CloseBraceToken | SyntaxKind.OpenParenToken | SyntaxKind.CloseParenToken | SyntaxKind.OpenBracketToken | SyntaxKind.CloseBracketToken | SyntaxKind.DotToken | SyntaxKind.DotDotDotToken | SyntaxKind.SemicolonToken | SyntaxKind.CommaToken | SyntaxKind.LessThanToken | SyntaxKind.LessThanSlashToken | SyntaxKind.GreaterThanToken | SyntaxKind.LessThanEqualsToken | SyntaxKind.GreaterThanEqualsToken | SyntaxKind.EqualsEqualsToken | SyntaxKind.ExclamationEqualsToken | SyntaxKind.EqualsEqualsEqualsToken | SyntaxKind.ExclamationEqualsEqualsToken | SyntaxKind.EqualsGreaterThanToken | SyntaxKind.PlusToken | SyntaxKind.MinusToken | SyntaxKind.AsteriskToken | SyntaxKind.AsteriskAsteriskToken | SyntaxKind.SlashToken | SyntaxKind.PercentToken | SyntaxKind.PlusPlusToken | SyntaxKind.MinusMinusToken | SyntaxKind.LessThanLessThanToken | SyntaxKind.GreaterThanGreaterThanToken | SyntaxKind.GreaterThanGreaterThanGreaterThanToken | SyntaxKind.AmpersandToken | SyntaxKind.BarToken | SyntaxKind.CaretToken | SyntaxKind.ExclamationToken | SyntaxKind.TildeToken | SyntaxKind.AmpersandAmpersandToken | SyntaxKind.BarBarToken | SyntaxKind.QuestionToken | SyntaxKind.ColonToken | SyntaxKind.AtToken | SyntaxKind.EqualsToken | SyntaxKind.PlusEqualsToken | SyntaxKind.MinusEqualsToken | SyntaxKind.AsteriskEqualsToken | SyntaxKind.AsteriskAsteriskEqualsToken | SyntaxKind.SlashEqualsToken | SyntaxKind.PercentEqualsToken | SyntaxKind.LessThanLessThanEqualsToken | SyntaxKind.GreaterThanGreaterThanEqualsToken | SyntaxKind.GreaterThanGreaterThanGreaterThanEqualsToken | SyntaxKind.AmpersandEqualsToken | SyntaxKind.BarEqualsToken | SyntaxKind.CaretEqualsToken | SyntaxKind.Identifier | SyntaxKind.BreakKeyword | SyntaxKind.CaseKeyword | SyntaxKind.CatchKeyword | SyntaxKind.ClassKeyword | SyntaxKind.ConstKeyword | SyntaxKind.ContinueKeyword | SyntaxKind.DebuggerKeyword | SyntaxKind.DefaultKeyword | SyntaxKind.DeleteKeyword | SyntaxKind.DoKeyword | SyntaxKind.ElseKeyword | SyntaxKind.EnumKeyword | SyntaxKind.ExportKeyword | SyntaxKind.ExtendsKeyword | SyntaxKind.FalseKeyword | SyntaxKind.FinallyKeyword | SyntaxKind.ForKeyword | SyntaxKind.FunctionKeyword | SyntaxKind.IfKeyword | SyntaxKind.ImportKeyword | SyntaxKind.InKeyword | SyntaxKind.InstanceOfKeyword | SyntaxKind.NewKeyword | SyntaxKind.NullKeyword | SyntaxKind.ReturnKeyword | SyntaxKind.SuperKeyword | SyntaxKind.SwitchKeyword | SyntaxKind.ThisKeyword | SyntaxKind.ThrowKeyword | SyntaxKind.TrueKeyword | SyntaxKind.TryKeyword | SyntaxKind.TypeOfKeyword | SyntaxKind.VarKeyword | SyntaxKind.VoidKeyword | SyntaxKind.WhileKeyword | SyntaxKind.WithKeyword | SyntaxKind.ImplementsKeyword | SyntaxKind.InterfaceKeyword | SyntaxKind.LetKeyword | SyntaxKind.PackageKeyword | SyntaxKind.PrivateKeyword | SyntaxKind.ProtectedKeyword | SyntaxKind.PublicKeyword | SyntaxKind.StaticKeyword | SyntaxKind.YieldKeyword | SyntaxKind.AbstractKeyword | SyntaxKind.AsKeyword | SyntaxKind.AnyKeyword | SyntaxKind.AsyncKeyword | SyntaxKind.AwaitKeyword | SyntaxKind.BooleanKeyword | SyntaxKind.ConstructorKeyword | SyntaxKind.DeclareKeyword | SyntaxKind.GetKeyword | SyntaxKind.InferKeyword | SyntaxKind.IsKeyword | SyntaxKind.KeyOfKeyword | SyntaxKind.ModuleKeyword | SyntaxKind.NamespaceKeyword | SyntaxKind.NeverKeyword | SyntaxKind.ReadonlyKeyword | SyntaxKind.RequireKeyword | SyntaxKind.NumberKeyword | SyntaxKind.ObjectKeyword | SyntaxKind.SetKeyword | SyntaxKind.StringKeyword | SyntaxKind.SymbolKeyword | SyntaxKind.TypeKeyword | SyntaxKind.UndefinedKeyword | SyntaxKind.UniqueKeyword | SyntaxKind.UnknownKeyword | SyntaxKind.FromKeyword | SyntaxKind.GlobalKeyword | SyntaxKind.OfKeyword | SyntaxKind.QualifiedName | SyntaxKind.ComputedPropertyName | SyntaxKind.TypeParameter | SyntaxKind.Parameter | SyntaxKind.Decorator | SyntaxKind.PropertySignature | SyntaxKind.PropertyDeclaration | SyntaxKind.MethodSignature | SyntaxKind.MethodDeclaration | SyntaxKind.Constructor | SyntaxKind.GetAccessor | SyntaxKind.SetAccessor | SyntaxKind.CallSignature | SyntaxKind.ConstructSignature | SyntaxKind.IndexSignature | SyntaxKind.TypePredicate | SyntaxKind.TypeReference | SyntaxKind.FunctionType | SyntaxKind.ConstructorType | SyntaxKind.TypeQuery | SyntaxKind.TypeLiteral | SyntaxKind.ArrayType | SyntaxKind.TupleType | SyntaxKind.UnionType | SyntaxKind.IntersectionType | SyntaxKind.ConditionalType | SyntaxKind.InferType | SyntaxKind.ParenthesizedType | SyntaxKind.ThisType | SyntaxKind.TypeOperator | SyntaxKind.IndexedAccessType | SyntaxKind.MappedType | SyntaxKind.LiteralType | SyntaxKind.ImportType | SyntaxKind.ObjectBindingPattern | SyntaxKind.ArrayBindingPattern | SyntaxKind.BindingElement | SyntaxKind.ArrayLiteralExpression | SyntaxKind.ObjectLiteralExpression | SyntaxKind.PropertyAccessExpression | SyntaxKind.ElementAccessExpression | SyntaxKind.CallExpression | SyntaxKind.NewExpression | SyntaxKind.TaggedTemplateExpression | SyntaxKind.TypeAssertionExpression | SyntaxKind.ParenthesizedExpression | SyntaxKind.FunctionExpression | SyntaxKind.ArrowFunction | SyntaxKind.DeleteExpression | SyntaxKind.TypeOfExpression | SyntaxKind.VoidExpression | SyntaxKind.AwaitExpression | SyntaxKind.ConditionalExpression | SyntaxKind.TemplateExpression | SyntaxKind.YieldExpression | SyntaxKind.SpreadElement | SyntaxKind.ClassExpression | SyntaxKind.OmittedExpression | SyntaxKind.ExpressionWithTypeArguments | SyntaxKind.AsExpression | SyntaxKind.NonNullExpression | SyntaxKind.MetaProperty | SyntaxKind.TemplateSpan | SyntaxKind.SemicolonClassElement | SyntaxKind.Block | SyntaxKind.VariableStatement | SyntaxKind.EmptyStatement | SyntaxKind.ExpressionStatement | SyntaxKind.IfStatement | SyntaxKind.DoStatement | SyntaxKind.WhileStatement | SyntaxKind.ForStatement | SyntaxKind.ForInStatement | SyntaxKind.ForOfStatement | SyntaxKind.ContinueStatement | SyntaxKind.BreakStatement | SyntaxKind.ReturnStatement | SyntaxKind.WithStatement | SyntaxKind.SwitchStatement | SyntaxKind.LabeledStatement | SyntaxKind.ThrowStatement | SyntaxKind.TryStatement | SyntaxKind.DebuggerStatement | SyntaxKind.VariableDeclaration | SyntaxKind.VariableDeclarationList | SyntaxKind.FunctionDeclaration | SyntaxKind.ClassDeclaration | SyntaxKind.InterfaceDeclaration | SyntaxKind.TypeAliasDeclaration | SyntaxKind.EnumDeclaration | SyntaxKind.ModuleDeclaration | SyntaxKind.ModuleBlock | SyntaxKind.CaseBlock | SyntaxKind.NamespaceExportDeclaration | SyntaxKind.ImportEqualsDeclaration | SyntaxKind.ImportDeclaration | SyntaxKind.ImportClause | SyntaxKind.NamespaceImport | SyntaxKind.NamedImports | SyntaxKind.ImportSpecifier | SyntaxKind.ExportAssignment | SyntaxKind.ExportDeclaration | SyntaxKind.NamedExports | SyntaxKind.ExportSpecifier | SyntaxKind.MissingDeclaration | SyntaxKind.ExternalModuleReference | SyntaxKind.JsxElement | SyntaxKind.JsxSelfClosingElement | SyntaxKind.JsxOpeningElement | SyntaxKind.JsxClosingElement | SyntaxKind.JsxFragment | SyntaxKind.JsxOpeningFragment | SyntaxKind.JsxClosingFragment | SyntaxKind.JsxAttribute | SyntaxKind.JsxAttributes | SyntaxKind.JsxSpreadAttribute | SyntaxKind.JsxExpression | SyntaxKind.CaseClause | SyntaxKind.DefaultClause | SyntaxKind.HeritageClause | SyntaxKind.CatchClause | SyntaxKind.PropertyAssignment | SyntaxKind.ShorthandPropertyAssignment | SyntaxKind.SpreadAssignment | SyntaxKind.EnumMember | SyntaxKind.SourceFile | SyntaxKind.Bundle | SyntaxKind.UnparsedSource | SyntaxKind.InputFiles | SyntaxKind.JSDocTypeExpression | SyntaxKind.JSDocAllType | SyntaxKind.JSDocUnknownType | SyntaxKind.JSDocNullableType | SyntaxKind.JSDocNonNullableType | SyntaxKind.JSDocOptionalType | SyntaxKind.JSDocFunctionType | SyntaxKind.JSDocVariadicType | SyntaxKind.JSDocComment | SyntaxKind.JSDocTypeLiteral | SyntaxKind.JSDocSignature | SyntaxKind.JSDocTag | SyntaxKind.JSDocAugmentsTag | SyntaxKind.JSDocClassTag | SyntaxKind.JSDocCallbackTag | SyntaxKind.JSDocParameterTag | SyntaxKind.JSDocReturnTag | SyntaxKind.JSDocTypeTag | SyntaxKind.JSDocTemplateTag | SyntaxKind.JSDocTypedefTag | SyntaxKind.JSDocPropertyTag | SyntaxKind.SyntaxList | SyntaxKind.NotEmittedStatement | SyntaxKind.PartiallyEmittedExpression | SyntaxKind.CommaListExpression | SyntaxKind.MergeDeclarationMarker | SyntaxKind.EndOfDeclarationMarker | SyntaxKind.Count;
+    function getOperatorPrecedence(nodeKind: SyntaxKind, operatorKind: SyntaxKind, hasArguments?: boolean): number;
+    function getBinaryOperatorPrecedence(kind: SyntaxKind): number;
+    function createDiagnosticCollection(): DiagnosticCollection;
+    /**
+     * Based heavily on the abstract 'Quote'/'QuoteJSONString' operation from ECMA-262 (24.3.2.2),
+     * but augmented for a few select characters (e.g. lineSeparator, paragraphSeparator, nextLine)
+     * Note that this doesn't actually wrap the input in double quotes.
+     */
+    function escapeString(s: string, quoteChar?: CharacterCodes.doubleQuote | CharacterCodes.singleQuote | CharacterCodes.backtick): string;
+    function isIntrinsicJsxName(name: __String | string): boolean;
+    function escapeNonAsciiString(s: string, quoteChar?: CharacterCodes.doubleQuote | CharacterCodes.singleQuote | CharacterCodes.backtick): string;
+    function getIndentString(level: number): string;
+    function getIndentSize(): number;
+    function createTextWriter(newLine: string): EmitTextWriter;
+    function getResolvedExternalModuleName(host: EmitHost, file: SourceFile, referenceFile?: SourceFile): string;
+    function getExternalModuleNameFromDeclaration(host: EmitHost, resolver: EmitResolver, declaration: ImportEqualsDeclaration | ImportDeclaration | ExportDeclaration | ModuleDeclaration | ImportTypeNode): string | undefined;
+    /**
+     * Resolves a local path to a path which is absolute to the base of the emit
+     */
+    function getExternalModuleNameFromPath(host: EmitHost, fileName: string, referencePath?: string): string;
+    function getOwnEmitOutputFilePath(sourceFile: SourceFile, host: EmitHost, extension: string): string;
+    function getDeclarationEmitOutputFilePath(sourceFile: SourceFile, host: EmitHost): string;
+    interface EmitFileNames {
+        jsFilePath: string;
+        sourceMapFilePath: string | undefined;
+        declarationFilePath: string | undefined;
+        declarationMapPath: string | undefined;
+        bundleInfoPath: string | undefined;
+    }
+    /**
+     * Gets the source files that are expected to have an emit output.
+     *
+     * Originally part of `forEachExpectedEmitFile`, this functionality was extracted to support
+     * transformations.
+     *
+     * @param host An EmitHost.
+     * @param targetSourceFile An optional target source file to emit.
+     */
+    function getSourceFilesToEmit(host: EmitHost, targetSourceFile?: SourceFile): ReadonlyArray<SourceFile>;
+    /** Don't call this for `--outFile`, just for `--outDir` or plain emit. `--outFile` needs additional checks. */
+    function sourceFileMayBeEmitted(sourceFile: SourceFile, options: CompilerOptions, isSourceFileFromExternalLibrary: (file: SourceFile) => boolean): boolean;
+    function getSourceFilePathInNewDir(sourceFile: SourceFile, host: EmitHost, newDirPath: string): string;
+    function writeFile(host: EmitHost, diagnostics: DiagnosticCollection, fileName: string, data: string, writeByteOrderMark: boolean, sourceFiles?: ReadonlyArray<SourceFile>): void;
+    function getLineOfLocalPosition(currentSourceFile: SourceFile, pos: number): number;
+    function getLineOfLocalPositionFromLineMap(lineMap: ReadonlyArray<number>, pos: number): number;
+    function getFirstConstructorWithBody(node: ClassLikeDeclaration): ConstructorDeclaration | undefined;
+    /** Get the type annotation for the value parameter. */
+    function getSetAccessorTypeAnnotationNode(accessor: SetAccessorDeclaration): TypeNode | undefined;
+    function getThisParameter(signature: SignatureDeclaration | JSDocSignature): ParameterDeclaration | undefined;
+    function parameterIsThisKeyword(parameter: ParameterDeclaration): boolean;
+    function isThisIdentifier(node: Node | undefined): boolean;
+    function identifierIsThisKeyword(id: Identifier): boolean;
+    function getAllAccessorDeclarations(declarations: NodeArray<Declaration>, accessor: AccessorDeclaration): AllAccessorDeclarations;
+    /**
+     * Gets the effective type annotation of a variable, parameter, or property. If the node was
+     * parsed in a JavaScript file, gets the type annotation from JSDoc.
+     */
+    function getEffectiveTypeAnnotationNode(node: Node): TypeNode | undefined;
+    function getTypeAnnotationNode(node: Node): TypeNode | undefined;
+    /**
+     * Gets the effective return type annotation of a signature. If the node was parsed in a
+     * JavaScript file, gets the return type annotation from JSDoc.
+     */
+    function getEffectiveReturnTypeNode(node: SignatureDeclaration | JSDocSignature): TypeNode | undefined;
+    /**
+     * Gets the effective type parameters. If the node was parsed in a
+     * JavaScript file, gets the type parameters from the `@template` tag from JSDoc.
+     */
+    function getEffectiveTypeParameterDeclarations(node: DeclarationWithTypeParameters): ReadonlyArray<TypeParameterDeclaration>;
+    function getJSDocTypeParameterDeclarations(node: DeclarationWithTypeParameters): ReadonlyArray<TypeParameterDeclaration>;
+    /**
+     * Gets the effective type annotation of the value parameter of a set accessor. If the node
+     * was parsed in a JavaScript file, gets the type annotation from JSDoc.
+     */
+    function getEffectiveSetAccessorTypeAnnotationNode(node: SetAccessorDeclaration): TypeNode | undefined;
+    function emitNewLineBeforeLeadingComments(lineMap: ReadonlyArray<number>, writer: EmitTextWriter, node: TextRange, leadingComments: ReadonlyArray<CommentRange> | undefined): void;
+    function emitNewLineBeforeLeadingCommentsOfPosition(lineMap: ReadonlyArray<number>, writer: EmitTextWriter, pos: number, leadingComments: ReadonlyArray<CommentRange> | undefined): void;
+    function emitNewLineBeforeLeadingCommentOfPosition(lineMap: ReadonlyArray<number>, writer: EmitTextWriter, pos: number, commentPos: number): void;
+    function emitComments(text: string, lineMap: ReadonlyArray<number>, writer: EmitTextWriter, comments: ReadonlyArray<CommentRange> | undefined, leadingSeparator: boolean, trailingSeparator: boolean, newLine: string, writeComment: (text: string, lineMap: ReadonlyArray<number>, writer: EmitTextWriter, commentPos: number, commentEnd: number, newLine: string) => void): void;
+    /**
+     * Detached comment is a comment at the top of file or function body that is separated from
+     * the next statement by space.
+     */
+    function emitDetachedComments(text: string, lineMap: ReadonlyArray<number>, writer: EmitTextWriter, writeComment: (text: string, lineMap: ReadonlyArray<number>, writer: EmitTextWriter, commentPos: number, commentEnd: number, newLine: string) => void, node: TextRange, newLine: string, removeComments: boolean): {
+        nodePos: number;
+        detachedCommentEndPos: number;
+    } | undefined;
+    function writeCommentRange(text: string, lineMap: ReadonlyArray<number>, writer: EmitTextWriter, commentPos: number, commentEnd: number, newLine: string): void;
+    function hasModifiers(node: Node): boolean;
+    function hasModifier(node: Node, flags: ModifierFlags): boolean;
+    function hasStaticModifier(node: Node): boolean;
+    function hasReadonlyModifier(node: Node): boolean;
+    function getSelectedModifierFlags(node: Node, flags: ModifierFlags): ModifierFlags;
+    function getModifierFlags(node: Node): ModifierFlags;
+    function getModifierFlagsNoCache(node: Node): ModifierFlags;
+    function modifierToFlag(token: SyntaxKind): ModifierFlags;
+    function isLogicalOperator(token: SyntaxKind): boolean;
+    function isAssignmentOperator(token: SyntaxKind): boolean;
+    /** Get `C` given `N` if `N` is in the position `class C extends N` where `N` is an ExpressionWithTypeArguments. */
+    function tryGetClassExtendingExpressionWithTypeArguments(node: Node): ClassLikeDeclaration | undefined;
+    function isAssignmentExpression(node: Node, excludeCompoundAssignment: true): node is AssignmentExpression<EqualsToken>;
+    function isAssignmentExpression(node: Node, excludeCompoundAssignment?: false): node is AssignmentExpression<AssignmentOperatorToken>;
+    function isDestructuringAssignment(node: Node): node is DestructuringAssignment;
+    function isExpressionWithTypeArgumentsInClassExtendsClause(node: Node): boolean;
+    function isExpressionWithTypeArgumentsInClassImplementsClause(node: Node): node is ExpressionWithTypeArguments;
+    function isEntityNameExpression(node: Node): node is EntityNameExpression;
+    function isPropertyAccessEntityNameExpression(node: Node): node is PropertyAccessEntityNameExpression;
+    function isPrototypeAccess(node: Node): node is PropertyAccessExpression;
+    function isRightSideOfQualifiedNameOrPropertyAccess(node: Node): boolean;
+    function isEmptyObjectLiteral(expression: Node): boolean;
+    function isEmptyArrayLiteral(expression: Node): boolean;
+    function getLocalSymbolForExportDefault(symbol: Symbol): Symbol | undefined;
+    /** Return ".ts", ".d.ts", or ".tsx", if that is the extension. */
+    function tryExtractTypeScriptExtension(fileName: string): string | undefined;
+    /**
+     * Converts a string to a base-64 encoded ASCII string.
+     */
+    function convertToBase64(input: string): string;
+    function base64encode(host: {
+        base64encode?(input: string): string;
+    } | undefined, input: string): string;
+    function base64decode(host: {
+        base64decode?(input: string): string;
+    } | undefined, input: string): string;
+    function getNewLineCharacter(options: CompilerOptions | PrinterOptions, getNewLine?: () => string): string;
+    function formatSyntaxKind(kind: SyntaxKind | undefined): string;
+    function formatModifierFlags(flags: ModifierFlags | undefined): string;
+    function formatTransformFlags(flags: TransformFlags | undefined): string;
+    function formatEmitFlags(flags: EmitFlags | undefined): string;
+    function formatSymbolFlags(flags: SymbolFlags | undefined): string;
+    function formatTypeFlags(flags: TypeFlags | undefined): string;
+    function formatObjectFlags(flags: ObjectFlags | undefined): string;
+    /**
+     * Creates a new TextRange from the provided pos and end.
+     *
+     * @param pos The start position.
+     * @param end The end position.
+     */
+    function createRange(pos: number, end: number): TextRange;
+    /**
+     * Creates a new TextRange from a provided range with a new end position.
+     *
+     * @param range A TextRange.
+     * @param end The new end position.
+     */
+    function moveRangeEnd(range: TextRange, end: number): TextRange;
+    /**
+     * Creates a new TextRange from a provided range with a new start position.
+     *
+     * @param range A TextRange.
+     * @param pos The new Start position.
+     */
+    function moveRangePos(range: TextRange, pos: number): TextRange;
+    /**
+     * Moves the start position of a range past any decorators.
+     */
+    function moveRangePastDecorators(node: Node): TextRange;
+    /**
+     * Moves the start position of a range past any decorators or modifiers.
+     */
+    function moveRangePastModifiers(node: Node): TextRange;
+    /**
+     * Determines whether a TextRange has the same start and end positions.
+     *
+     * @param range A TextRange.
+     */
+    function isCollapsedRange(range: TextRange): boolean;
+    /**
+     * Creates a new TextRange for a token at the provides start position.
+     *
+     * @param pos The start position.
+     * @param token The token.
+     */
+    function createTokenRange(pos: number, token: SyntaxKind): TextRange;
+    function rangeIsOnSingleLine(range: TextRange, sourceFile: SourceFile): boolean;
+    function rangeStartPositionsAreOnSameLine(range1: TextRange, range2: TextRange, sourceFile: SourceFile): boolean;
+    function rangeEndPositionsAreOnSameLine(range1: TextRange, range2: TextRange, sourceFile: SourceFile): boolean;
+    function rangeStartIsOnSameLineAsRangeEnd(range1: TextRange, range2: TextRange, sourceFile: SourceFile): boolean;
+    function rangeEndIsOnSameLineAsRangeStart(range1: TextRange, range2: TextRange, sourceFile: SourceFile): boolean;
+    function positionsAreOnSameLine(pos1: number, pos2: number, sourceFile: SourceFile): boolean;
+    function getStartPositionOfRange(range: TextRange, sourceFile: SourceFile): number;
+    /**
+     * Determines whether a name was originally the declaration name of an enum or namespace
+     * declaration.
+     */
+    function isDeclarationNameOfEnumOrNamespace(node: Identifier): boolean;
+    function getInitializedVariables(node: VariableDeclarationList): ReadonlyArray<VariableDeclaration>;
+    function isWatchSet(options: CompilerOptions): boolean | undefined;
+    function closeFileWatcher(watcher: FileWatcher): void;
+    function getCheckFlags(symbol: Symbol): CheckFlags;
+    function getDeclarationModifierFlagsFromSymbol(s: Symbol): ModifierFlags;
+    function skipAlias(symbol: Symbol, checker: TypeChecker): Symbol;
+    /** See comment on `declareModuleMember` in `binder.ts`. */
+    function getCombinedLocalAndExportSymbolFlags(symbol: Symbol): SymbolFlags;
+    function isWriteOnlyAccess(node: Node): boolean;
+    function isWriteAccess(node: Node): boolean;
+    function compareDataObjects(dst: any, src: any): boolean;
+    /**
+     * clears already present map by calling onDeleteExistingValue callback before deleting that key/value
+     */
+    function clearMap<T>(map: Map<T>, onDeleteValue: (valueInMap: T, key: string) => void): void;
+    interface MutateMapOptions<T, U> {
+        createNewValue(key: string, valueInNewMap: U): T;
+        onDeleteValue(existingValue: T, key: string): void;
+        /**
+         * If present this is called with the key when there is value for that key both in new map as well as existing map provided
+         * Caller can then decide to update or remove this key.
+         * If the key is removed, caller will get callback of createNewValue for that key.
+         * If this callback is not provided, the value of such keys is not updated.
+         */
+        onExistingValue?(existingValue: T, valueInNewMap: U, key: string): void;
+    }
+    /**
+     * Mutates the map with newMap such that keys in map will be same as newMap.
+     */
+    function mutateMap<T, U>(map: Map<T>, newMap: ReadonlyMap<U>, options: MutateMapOptions<T, U>): void;
+    /** Calls `callback` on `directory` and every ancestor directory it has, returning the first defined result. */
+    function forEachAncestorDirectory<T>(directory: string, callback: (directory: string) => T | undefined): T | undefined;
+    function isAbstractConstructorType(type: Type): boolean;
+    function isAbstractConstructorSymbol(symbol: Symbol): boolean;
+    function getClassLikeDeclarationOfSymbol(symbol: Symbol): ClassLikeDeclaration | undefined;
+    function getObjectFlags(type: Type): ObjectFlags;
+    function typeHasCallOrConstructSignatures(type: Type, checker: TypeChecker): boolean;
+    function forSomeAncestorDirectory(directory: string, callback: (directory: string) => boolean): boolean;
+    function isUMDExportSymbol(symbol: Symbol | undefined): boolean | undefined;
+    function showModuleSpecifier({ moduleSpecifier }: ImportDeclaration): string;
+    function getLastChild(node: Node): Node | undefined;
+    /** Add a value to a set, and return true if it wasn't already present. */
+    function addToSeen(seen: Map<true>, key: string | number): boolean;
+    function addToSeen<T>(seen: Map<T>, key: string | number, value: T): boolean;
+    function isObjectTypeDeclaration(node: Node): node is ObjectTypeDeclaration;
+}
 declare namespace ts {
     function getDefaultLibFileName(options: CompilerOptions): string;
     function textSpanEnd(span: TextSpan): number;
@@ -3113,6 +6605,7 @@ declare namespace ts {
     function textSpanIntersectsWithPosition(span: TextSpan, position: number): boolean;
     function textSpanIntersection(span1: TextSpan, span2: TextSpan): TextSpan | undefined;
     function createTextSpan(start: number, length: number): TextSpan;
+    function createTextRange(pos: number, end?: number): TextRange;
     function createTextSpanFromBounds(start: number, end: number): TextSpan;
     function textChangeRangeNewSpan(range: TextChangeRange): TextSpan;
     function textChangeRangeIsUnchanged(range: TextChangeRange): boolean;
@@ -3189,6 +6682,10 @@ declare namespace ts {
      */
     function unescapeIdentifier(id: string): string;
     function getNameOfJSDocTypedef(declaration: JSDocTypedefTag): Identifier | undefined;
+    /** @internal */
+    function isNamedDeclaration(node: Node): node is NamedDeclaration & {
+        name: DeclarationName;
+    };
     function getNameOfDeclaration(declaration: Declaration | Expression): DeclarationName;
     /**
      * Gets the JSDoc parameter tags for the node if present.
@@ -3270,6 +6767,7 @@ declare namespace ts {
     function isCallSignatureDeclaration(node: Node): node is CallSignatureDeclaration;
     function isConstructSignatureDeclaration(node: Node): node is ConstructSignatureDeclaration;
     function isIndexSignatureDeclaration(node: Node): node is IndexSignatureDeclaration;
+    function isGetOrSetAccessorDeclaration(node: Node): node is AccessorDeclaration;
     function isTypePredicateNode(node: Node): node is TypePredicateNode;
     function isTypeReferenceNode(node: Node): node is TypeReferenceNode;
     function isFunctionTypeNode(node: Node): node is FunctionTypeNode;
@@ -3412,25 +6910,39 @@ declare namespace ts {
     function isJSDocSignature(node: Node): node is JSDocSignature;
 }
 declare namespace ts {
+    function isSyntaxList(n: Node): n is SyntaxList;
+    function isNode(node: Node): boolean;
+    function isNodeKind(kind: SyntaxKind): boolean;
     /**
      * True if node is of some token syntax kind.
      * For example, this is true for an IfKeyword but not for an IfStatement.
      * Literals are considered tokens, except TemplateLiteral, but does include TemplateHead/Middle/Tail.
      */
     function isToken(n: Node): boolean;
+    function isNodeArray<T extends Node>(array: ReadonlyArray<T>): array is NodeArray<T>;
+    function isLiteralKind(kind: SyntaxKind): boolean;
     function isLiteralExpression(node: Node): node is LiteralExpression;
+    function isTemplateLiteralKind(kind: SyntaxKind): boolean;
     type TemplateLiteralToken = NoSubstitutionTemplateLiteral | TemplateHead | TemplateMiddle | TemplateTail;
     function isTemplateLiteralToken(node: Node): node is TemplateLiteralToken;
     function isTemplateMiddleOrTemplateTail(node: Node): node is TemplateMiddle | TemplateTail;
     function isStringTextContainingNode(node: Node): node is StringLiteral | TemplateLiteralToken;
+    function isGeneratedIdentifier(node: Node): node is GeneratedIdentifier;
+    function isModifierKind(token: SyntaxKind): boolean;
+    function isParameterPropertyModifier(kind: SyntaxKind): boolean;
+    function isClassMemberModifier(idToken: SyntaxKind): boolean;
     function isModifier(node: Node): node is Modifier;
     function isEntityName(node: Node): node is EntityName;
     function isPropertyName(node: Node): node is PropertyName;
     function isBindingName(node: Node): node is BindingName;
     function isFunctionLike(node: Node): node is SignatureDeclaration;
+    function isFunctionLikeDeclaration(node: Node): node is FunctionLikeDeclaration;
+    function isFunctionLikeKind(kind: SyntaxKind): boolean;
+    function isFunctionOrModuleBlock(node: Node): boolean;
     function isClassElement(node: Node): node is ClassElement;
     function isClassLike(node: Node): node is ClassLikeDeclaration;
     function isAccessor(node: Node): node is AccessorDeclaration;
+    function isMethodOrAccessor(node: Node): node is MethodDeclaration | AccessorDeclaration;
     function isTypeElement(node: Node): node is TypeElement;
     function isClassOrTypeElement(node: Node): node is ClassElement | TypeElement;
     function isObjectLiteralElementLike(node: Node): node is ObjectLiteralElementLike;
@@ -3441,24 +6953,405 @@ declare namespace ts {
      */
     function isTypeNode(node: Node): node is TypeNode;
     function isFunctionOrConstructorTypeNode(node: Node): node is FunctionTypeNode | ConstructorTypeNode;
+    function isBindingPattern(node: Node | undefined): node is BindingPattern;
+    function isAssignmentPattern(node: Node): node is AssignmentPattern;
+    function isArrayBindingElement(node: Node): node is ArrayBindingElement;
+    /**
+     * Determines whether the BindingOrAssignmentElement is a BindingElement-like declaration
+     */
+    function isDeclarationBindingElement(bindingElement: BindingOrAssignmentElement): bindingElement is VariableDeclaration | ParameterDeclaration | BindingElement;
+    /**
+     * Determines whether a node is a BindingOrAssignmentPattern
+     */
+    function isBindingOrAssignmentPattern(node: BindingOrAssignmentElementTarget): node is BindingOrAssignmentPattern;
+    /**
+     * Determines whether a node is an ObjectBindingOrAssignmentPattern
+     */
+    function isObjectBindingOrAssignmentPattern(node: BindingOrAssignmentElementTarget): node is ObjectBindingOrAssignmentPattern;
+    /**
+     * Determines whether a node is an ArrayBindingOrAssignmentPattern
+     */
+    function isArrayBindingOrAssignmentPattern(node: BindingOrAssignmentElementTarget): node is ArrayBindingOrAssignmentPattern;
+    function isPropertyAccessOrQualifiedNameOrImportTypeNode(node: Node): node is PropertyAccessExpression | QualifiedName | ImportTypeNode;
     function isPropertyAccessOrQualifiedName(node: Node): node is PropertyAccessExpression | QualifiedName;
     function isCallLikeExpression(node: Node): node is CallLikeExpression;
     function isCallOrNewExpression(node: Node): node is CallExpression | NewExpression;
     function isTemplateLiteral(node: Node): node is TemplateLiteral;
+    function isLeftHandSideExpression(node: Node): node is LeftHandSideExpression;
+    function isUnaryExpression(node: Node): node is UnaryExpression;
+    function isUnaryExpressionWithWrite(expr: Node): expr is PrefixUnaryExpression | PostfixUnaryExpression;
+    /**
+     * Determines whether a node is an expression based only on its kind.
+     * Use `isExpressionNode` if not in transforms.
+     */
+    function isExpression(node: Node): node is Expression;
     function isAssertionExpression(node: Node): node is AssertionExpression;
+    function isPartiallyEmittedExpression(node: Node): node is PartiallyEmittedExpression;
+    function isNotEmittedStatement(node: Node): node is NotEmittedStatement;
+    function isNotEmittedOrPartiallyEmittedNode(node: Node): node is NotEmittedStatement | PartiallyEmittedExpression;
     function isIterationStatement(node: Node, lookInLabeledStatements: false): node is IterationStatement;
     function isIterationStatement(node: Node, lookInLabeledStatements: boolean): node is IterationStatement | LabeledStatement;
+    function isForInOrOfStatement(node: Node): node is ForInOrOfStatement;
+    function isConciseBody(node: Node): node is ConciseBody;
+    function isFunctionBody(node: Node): node is FunctionBody;
+    function isForInitializer(node: Node): node is ForInitializer;
+    function isModuleBody(node: Node): node is ModuleBody;
+    function isNamespaceBody(node: Node): node is NamespaceBody;
+    function isJSDocNamespaceBody(node: Node): node is JSDocNamespaceBody;
+    function isNamedImportBindings(node: Node): node is NamedImportBindings;
+    function isModuleOrEnumDeclaration(node: Node): node is ModuleDeclaration | EnumDeclaration;
+    function isDeclaration(node: Node): node is NamedDeclaration;
+    function isDeclarationStatement(node: Node): node is DeclarationStatement;
+    /**
+     * Determines whether the node is a statement that is not also a declaration
+     */
+    function isStatementButNotDeclaration(node: Node): node is Statement;
+    function isStatement(node: Node): node is Statement;
+    function isModuleReference(node: Node): node is ModuleReference;
+    function isJsxTagNameExpression(node: Node): node is JsxTagNameExpression;
+    function isJsxChild(node: Node): node is JsxChild;
+    function isJsxAttributeLike(node: Node): node is JsxAttributeLike;
+    function isStringLiteralOrJsxExpression(node: Node): node is StringLiteral | JsxExpression;
     function isJsxOpeningLikeElement(node: Node): node is JsxOpeningLikeElement;
     function isCaseOrDefaultClause(node: Node): node is CaseOrDefaultClause;
+    /** True if node is of some JSDoc syntax kind. */
+    function isJSDocNode(node: Node): boolean;
     /** True if node is of a kind that may contain comment text. */
     function isJSDocCommentContainingNode(node: Node): boolean;
+    function isJSDocTag(node: Node): boolean;
     function isSetAccessor(node: Node): node is SetAccessorDeclaration;
     function isGetAccessor(node: Node): node is GetAccessorDeclaration;
+    /** True if has jsdoc nodes attached to it. */
+    function hasJSDocNodes(node: Node): node is HasJSDoc;
+    /** True if has type node attached to it. */
+    function hasType(node: Node): node is HasType;
+    function couldHaveType(node: Node): node is HasType;
+    /** True if has initializer node attached to it. */
+    function hasInitializer(node: Node): node is HasInitializer;
+    /** True if has initializer node attached to it. */
+    function hasOnlyExpressionInitializer(node: Node): node is HasExpressionInitializer;
     function isObjectLiteralElement(node: Node): node is ObjectLiteralElement;
+    function isTypeReferenceType(node: Node): node is TypeReferenceType;
+    function guessIndentation(lines: string[]): number | undefined;
     function isStringLiteralLike(node: Node): node is StringLiteralLike;
 }
+declare namespace ts {
+    /** @internal */
+    function isNamedImportsOrExports(node: Node): node is NamedImportsOrExports;
+    interface ObjectAllocator {
+        getNodeConstructor(): new (kind: SyntaxKind, pos?: number, end?: number) => Node;
+        getTokenConstructor(): new <TKind extends SyntaxKind>(kind: TKind, pos?: number, end?: number) => Token<TKind>;
+        getIdentifierConstructor(): new (kind: SyntaxKind.Identifier, pos?: number, end?: number) => Identifier;
+        getSourceFileConstructor(): new (kind: SyntaxKind.SourceFile, pos?: number, end?: number) => SourceFile;
+        getSymbolConstructor(): new (flags: SymbolFlags, name: __String) => Symbol;
+        getTypeConstructor(): new (checker: TypeChecker, flags: TypeFlags) => Type;
+        getSignatureConstructor(): new (checker: TypeChecker) => Signature;
+        getSourceMapSourceConstructor(): new (fileName: string, text: string, skipTrivia?: (pos: number) => number) => SourceMapSource;
+    }
+    let objectAllocator: ObjectAllocator;
+    function formatStringFromArgs(text: string, args: ArrayLike<string>, baseIndex?: number): string;
+    let localizedDiagnosticMessages: MapLike<string> | undefined;
+    function getLocaleSpecificMessage(message: DiagnosticMessage): string;
+    function createFileDiagnostic(file: SourceFile, start: number, length: number, message: DiagnosticMessage, ...args: (string | number | undefined)[]): DiagnosticWithLocation;
+    function formatMessage(_dummy: any, message: DiagnosticMessage): string;
+    function createCompilerDiagnostic(message: DiagnosticMessage, ...args: (string | number | undefined)[]): Diagnostic;
+    function createCompilerDiagnosticFromMessageChain(chain: DiagnosticMessageChain): Diagnostic;
+    function chainDiagnosticMessages(details: DiagnosticMessageChain | undefined, message: DiagnosticMessage, ...args: (string | undefined)[]): DiagnosticMessageChain;
+    function concatenateDiagnosticMessageChains(headChain: DiagnosticMessageChain, tailChain: DiagnosticMessageChain): DiagnosticMessageChain;
+    function compareDiagnostics(d1: Diagnostic, d2: Diagnostic): Comparison;
+    function getEmitScriptTarget(compilerOptions: CompilerOptions): ScriptTarget;
+    function getEmitModuleKind(compilerOptions: {
+        module?: CompilerOptions["module"];
+        target?: CompilerOptions["target"];
+    }): ModuleKind;
+    function getEmitModuleResolutionKind(compilerOptions: CompilerOptions): ModuleResolutionKind;
+    function unreachableCodeIsError(options: CompilerOptions): boolean;
+    function unusedLabelIsError(options: CompilerOptions): boolean;
+    function getAreDeclarationMapsEnabled(options: CompilerOptions): boolean;
+    function getAllowSyntheticDefaultImports(compilerOptions: CompilerOptions): boolean;
+    function getEmitDeclarations(compilerOptions: CompilerOptions): boolean;
+    type StrictOptionName = "noImplicitAny" | "noImplicitThis" | "strictNullChecks" | "strictFunctionTypes" | "strictPropertyInitialization" | "alwaysStrict";
+    function getStrictOptionValue(compilerOptions: CompilerOptions, flag: StrictOptionName): boolean;
+    function hasZeroOrOneAsteriskCharacter(str: string): boolean;
+    /**
+     * Internally, we represent paths as strings with '/' as the directory separator.
+     * When we make system calls (eg: LanguageServiceHost.getDirectory()),
+     * we expect the host to correctly handle paths in our specified format.
+     */
+    const directorySeparator = "/";
+    /**
+     * Normalize path separators.
+     */
+    function normalizeSlashes(path: string): string;
+    /**
+     * Returns length of the root part of a path or URL (i.e. length of "/", "x:/", "//server/share/, file:///user/files").
+     *
+     * For example:
+     * ```ts
+     * getRootLength("a") === 0                   // ""
+     * getRootLength("/") === 1                   // "/"
+     * getRootLength("c:") === 2                  // "c:"
+     * getRootLength("c:d") === 0                 // ""
+     * getRootLength("c:/") === 3                 // "c:/"
+     * getRootLength("c:\\") === 3                // "c:\\"
+     * getRootLength("//server") === 7            // "//server"
+     * getRootLength("//server/share") === 8      // "//server/"
+     * getRootLength("\\\\server") === 7          // "\\\\server"
+     * getRootLength("\\\\server\\share") === 8   // "\\\\server\\"
+     * getRootLength("file:///path") === 8        // "file:///"
+     * getRootLength("file:///c:") === 10         // "file:///c:"
+     * getRootLength("file:///c:d") === 8         // "file:///"
+     * getRootLength("file:///c:/path") === 11    // "file:///c:/"
+     * getRootLength("file://server") === 13      // "file://server"
+     * getRootLength("file://server/path") === 14 // "file://server/"
+     * getRootLength("http://server") === 13      // "http://server"
+     * getRootLength("http://server/path") === 14 // "http://server/"
+     * ```
+     */
+    function getRootLength(path: string): number;
+    function normalizePath(path: string): string;
+    function normalizePathAndParts(path: string): {
+        path: string;
+        parts: string[];
+    };
+    /**
+     * Returns the path except for its basename. Semantics align with NodeJS's `path.dirname`
+     * except that we support URL's as well.
+     *
+     * ```ts
+     * getDirectoryPath("/path/to/file.ext") === "/path/to"
+     * getDirectoryPath("/path/to/") === "/path"
+     * getDirectoryPath("/") === "/"
+     * ```
+     */
+    function getDirectoryPath(path: Path): Path;
+    /**
+     * Returns the path except for its basename. Semantics align with NodeJS's `path.dirname`
+     * except that we support URL's as well.
+     *
+     * ```ts
+     * getDirectoryPath("/path/to/file.ext") === "/path/to"
+     * getDirectoryPath("/path/to/") === "/path"
+     * getDirectoryPath("/") === "/"
+     * ```
+     */
+    function getDirectoryPath(path: string): string;
+    function isUrl(path: string): boolean;
+    function pathIsRelative(path: string): boolean;
+    /**
+     * Determines whether a path is an absolute path (e.g. starts with `/`, or a dos path
+     * like `c:`, `c:\` or `c:/`).
+     */
+    function isRootedDiskPath(path: string): boolean;
+    /**
+     * Determines whether a path consists only of a path root.
+     */
+    function isDiskPathRoot(path: string): boolean;
+    function convertToRelativePath(absoluteOrRelativePath: string, basePath: string, getCanonicalFileName: (path: string) => string): string;
+    /**
+     * Parse a path into an array containing a root component (at index 0) and zero or more path
+     * components (at indices > 0). The result is not normalized.
+     * If the path is relative, the root component is `""`.
+     * If the path is absolute, the root component includes the first path separator (`/`).
+     */
+    function getPathComponents(path: string, currentDirectory?: string): string[];
+    /**
+     * Reduce an array of path components to a more simplified path by navigating any
+     * `"."` or `".."` entries in the path.
+     */
+    function reducePathComponents(components: ReadonlyArray<string>): string[];
+    /**
+     * Parse a path into an array containing a root component (at index 0) and zero or more path
+     * components (at indices > 0). The result is normalized.
+     * If the path is relative, the root component is `""`.
+     * If the path is absolute, the root component includes the first path separator (`/`).
+     */
+    function getNormalizedPathComponents(path: string, currentDirectory: string | undefined): string[];
+    function getNormalizedAbsolutePath(fileName: string, currentDirectory: string | undefined): string;
+    /**
+     * Formats a parsed path consisting of a root component (at index 0) and zero or more path
+     * segments (at indices > 0).
+     */
+    function getPathFromPathComponents(pathComponents: ReadonlyArray<string>): string;
+}
+declare namespace ts {
+    function getPathComponentsRelativeTo(from: string, to: string, stringEqualityComparer: (a: string, b: string) => boolean, getCanonicalFileName: GetCanonicalFileName): string[];
+    function getRelativePathFromFile(from: string, to: string, getCanonicalFileName: GetCanonicalFileName): string;
+    /**
+     * Gets a relative path that can be used to traverse between `from` and `to`.
+     */
+    function getRelativePathFromDirectory(from: string, to: string, ignoreCase: boolean): string;
+    /**
+     * Gets a relative path that can be used to traverse between `from` and `to`.
+     */
+    function getRelativePathFromDirectory(fromDirectory: string, to: string, getCanonicalFileName: GetCanonicalFileName): string;
+    function getRelativePathToDirectoryOrUrl(directoryPathOrUrl: string, relativeOrAbsolutePath: string, currentDirectory: string, getCanonicalFileName: GetCanonicalFileName, isAbsolutePathAnUrl: boolean): string;
+    /**
+     * Ensures a path is either absolute (prefixed with `/` or `c:`) or dot-relative (prefixed
+     * with `./` or `../`) so as not to be confused with an unprefixed module name.
+     */
+    function ensurePathIsNonModuleName(path: string): string;
+    /**
+     * Returns the path except for its containing directory name.
+     * Semantics align with NodeJS's `path.basename` except that we support URL's as well.
+     *
+     * ```ts
+     * getBaseFileName("/path/to/file.ext") === "file.ext"
+     * getBaseFileName("/path/to/") === "to"
+     * getBaseFileName("/") === ""
+     * ```
+     */
+    function getBaseFileName(path: string): string;
+    /**
+     * Gets the portion of a path following the last (non-terminal) separator (`/`).
+     * Semantics align with NodeJS's `path.basename` except that we support URL's as well.
+     * If the base name has any one of the provided extensions, it is removed.
+     *
+     * ```ts
+     * getBaseFileName("/path/to/file.ext", ".ext", true) === "file"
+     * getBaseFileName("/path/to/file.js", ".ext", true) === "file.js"
+     * ```
+     */
+    function getBaseFileName(path: string, extensions: string | ReadonlyArray<string>, ignoreCase: boolean): string;
+    /**
+     * Combines paths. If a path is absolute, it replaces any previous path.
+     */
+    function combinePaths(path: string, ...paths: (string | undefined)[]): string;
+    /**
+     * Combines and resolves paths. If a path is absolute, it replaces any previous path. Any
+     * `.` and `..` path components are resolved.
+     */
+    function resolvePath(path: string, ...paths: (string | undefined)[]): string;
+    /**
+     * Determines whether a path has a trailing separator (`/` or `\\`).
+     */
+    function hasTrailingDirectorySeparator(path: string): boolean;
+    /**
+     * Removes a trailing directory separator from a path.
+     * @param path The path.
+     */
+    function removeTrailingDirectorySeparator(path: Path): Path;
+    function removeTrailingDirectorySeparator(path: string): string;
+    /**
+     * Adds a trailing directory separator to a path, if it does not already have one.
+     * @param path The path.
+     */
+    function ensureTrailingDirectorySeparator(path: Path): Path;
+    function ensureTrailingDirectorySeparator(path: string): string;
+    /**
+     * Performs a case-sensitive comparison of two paths.
+     */
+    function comparePathsCaseSensitive(a: string, b: string): Comparison;
+    /**
+     * Performs a case-insensitive comparison of two paths.
+     */
+    function comparePathsCaseInsensitive(a: string, b: string): Comparison;
+    function comparePaths(a: string, b: string, ignoreCase?: boolean): Comparison;
+    function comparePaths(a: string, b: string, currentDirectory: string, ignoreCase?: boolean): Comparison;
+    function containsPath(parent: string, child: string, ignoreCase?: boolean): boolean;
+    function containsPath(parent: string, child: string, currentDirectory: string, ignoreCase?: boolean): boolean;
+    function tryRemoveDirectoryPrefix(path: string, dirPath: string): string | undefined;
+    function hasExtension(fileName: string): boolean;
+    const commonPackageFolders: ReadonlyArray<string>;
+    function getRegularExpressionForWildcard(specs: ReadonlyArray<string> | undefined, basePath: string, usage: "files" | "directories" | "exclude"): string | undefined;
+    /**
+     * An "includes" path "foo" is implicitly a glob "foo/** /*" (without the space) if its last component has no extension,
+     * and does not contain any glob characters itself.
+     */
+    function isImplicitGlob(lastPathComponent: string): boolean;
+    interface FileSystemEntries {
+        readonly files: ReadonlyArray<string>;
+        readonly directories: ReadonlyArray<string>;
+    }
+    interface FileMatcherPatterns {
+        /** One pattern for each "include" spec. */
+        includeFilePatterns: ReadonlyArray<string> | undefined;
+        /** One pattern matching one of any of the "include" specs. */
+        includeFilePattern: string | undefined;
+        includeDirectoryPattern: string | undefined;
+        excludePattern: string | undefined;
+        basePaths: ReadonlyArray<string>;
+    }
+    /** @param path directory of the tsconfig.json */
+    function getFileMatcherPatterns(path: string, excludes: ReadonlyArray<string> | undefined, includes: ReadonlyArray<string> | undefined, useCaseSensitiveFileNames: boolean, currentDirectory: string): FileMatcherPatterns;
+    function getRegexFromPattern(pattern: string, useCaseSensitiveFileNames: boolean): RegExp;
+    /** @param path directory of the tsconfig.json */
+    function matchFiles(path: string, extensions: ReadonlyArray<string> | undefined, excludes: ReadonlyArray<string> | undefined, includes: ReadonlyArray<string> | undefined, useCaseSensitiveFileNames: boolean, currentDirectory: string, depth: number | undefined, getFileSystemEntries: (path: string) => FileSystemEntries): string[];
+    function ensureScriptKind(fileName: string, scriptKind: ScriptKind | undefined): ScriptKind;
+    function getScriptKindFromFileName(fileName: string): ScriptKind;
+    /**
+     *  List of supported extensions in order of file resolution precedence.
+     */
+    const supportedTypeScriptExtensions: ReadonlyArray<Extension>;
+    /** Must have ".d.ts" first because if ".ts" goes first, that will be detected as the extension instead of ".d.ts". */
+    const supportedTypescriptExtensionsForExtractExtension: ReadonlyArray<Extension>;
+    const supportedJavascriptExtensions: ReadonlyArray<Extension>;
+    function getSupportedExtensions(options?: CompilerOptions, extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): ReadonlyArray<string>;
+    function hasJavaScriptFileExtension(fileName: string): boolean;
+    function hasTypeScriptFileExtension(fileName: string): boolean;
+    function isSupportedSourceFileName(fileName: string, compilerOptions?: CompilerOptions, extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): boolean;
+    /**
+     * Extension boundaries by priority. Lower numbers indicate higher priorities, and are
+     * aligned to the offset of the highest priority extension in the
+     * allSupportedExtensions array.
+     */
+    enum ExtensionPriority {
+        TypeScriptFiles = 0,
+        DeclarationAndJavaScriptFiles = 2,
+        Highest = 0,
+        Lowest = 2
+    }
+    function getExtensionPriority(path: string, supportedExtensions: ReadonlyArray<string>): ExtensionPriority;
+    /**
+     * Adjusts an extension priority to be the highest priority within the same range.
+     */
+    function adjustExtensionPriority(extensionPriority: ExtensionPriority, supportedExtensions: ReadonlyArray<string>): ExtensionPriority;
+    /**
+     * Gets the next lowest extension priority for a given priority.
+     */
+    function getNextLowestExtensionPriority(extensionPriority: ExtensionPriority, supportedExtensions: ReadonlyArray<string>): ExtensionPriority;
+    function removeFileExtension(path: string): string;
+    function tryRemoveExtension(path: string, extension: string): string | undefined;
+    function removeExtension(path: string, extension: string): string;
+    function changeExtension<T extends string | Path>(path: T, newExtension: string): T;
+    function changeAnyExtension(path: string, ext: string): string;
+    function changeAnyExtension(path: string, ext: string, extensions: string | ReadonlyArray<string>, ignoreCase: boolean): string;
+    namespace Debug {
+        function showSymbol(symbol: Symbol): string;
+        function showSyntaxKind(node: Node): string;
+    }
+    function tryParsePattern(pattern: string): Pattern | undefined;
+    function positionIsSynthesized(pos: number): boolean;
+    /** True if an extension is one of the supported TypeScript extensions. */
+    function extensionIsTypeScript(ext: Extension): boolean;
+    function resolutionExtensionIsTypeScriptOrJson(ext: Extension): boolean;
+    /**
+     * Gets the extension from a path.
+     * Path must have a valid extension.
+     */
+    function extensionFromPath(path: string): Extension;
+    function isAnySupportedFileExtension(path: string): boolean;
+    function tryGetExtensionFromPath(path: string): Extension | undefined;
+    /**
+     * Gets the file extension for a path.
+     */
+    function getAnyExtensionFromPath(path: string): string;
+    /**
+     * Gets the file extension for a path, provided it is one of the provided extensions.
+     */
+    function getAnyExtensionFromPath(path: string, extensions: string | ReadonlyArray<string>, ignoreCase: boolean): string;
+    function isCheckJsEnabledForFile(sourceFile: SourceFile, compilerOptions: CompilerOptions): boolean | undefined;
+    const emptyFileSystemEntries: FileSystemEntries;
+    /**
+     * patternStrings contains both pattern strings (containing "*") and regular strings.
+     * Return an exact match if possible, or a pattern match, or undefined.
+     * (These are verified by verifyCompilerOptions to have 0 or 1 "*" characters.)
+     */
+    function matchPatternOrExact(patternStrings: ReadonlyArray<string>, candidate: string): string | Pattern | undefined;
+}
 declare namespace ts {
     function createNode(kind: SyntaxKind, pos?: number, end?: number): Node;
+    function isJSDocLikeText(text: string, start: number): boolean;
     /**
      * Invokes a callback for each child of the given node. The 'cbNode' callback is invoked for all child nodes
      * stored in properties. If a 'cbNodes' callback is specified, it is invoked for embedded arrays; otherwise,
@@ -3483,8 +7376,198 @@ declare namespace ts {
     function parseJsonText(fileName: string, sourceText: string): JsonSourceFile;
     function isExternalModule(file: SourceFile): boolean;
     function updateSourceFile(sourceFile: SourceFile, newText: string, textChangeRange: TextChangeRange, aggressiveChecks?: boolean): SourceFile;
+    function parseIsolatedJSDocComment(content: string, start?: number, length?: number): {
+        jsDoc: JSDoc;
+        diagnostics: Diagnostic[];
+    } | undefined;
+    function parseJSDocTypeExpressionForTests(content: string, start?: number, length?: number): {
+        jsDocTypeExpression: JSDocTypeExpression;
+        diagnostics: Diagnostic[];
+    } | undefined;
+    interface PragmaContext {
+        languageVersion: ScriptTarget;
+        pragmas?: PragmaMap;
+        checkJsDirective?: CheckJsDirective;
+        referencedFiles: FileReference[];
+        typeReferenceDirectives: FileReference[];
+        libReferenceDirectives: FileReference[];
+        amdDependencies: AmdDependency[];
+        hasNoDefaultLib?: boolean;
+        moduleName?: string;
+    }
+    function processCommentPragmas(context: PragmaContext, sourceText: string): void;
+    type PragmaDiagnosticReporter = (pos: number, length: number, message: DiagnosticMessage) => void;
+    function processPragmasIntoFields(context: PragmaContext, reportDiagnostic: PragmaDiagnosticReporter): void;
+    /** @internal */
+    function tagNamesAreEquivalent(lhs: JsxTagNameExpression, rhs: JsxTagNameExpression): boolean;
 }
 declare namespace ts {
+    const compileOnSaveCommandLineOption: CommandLineOption;
+    /**
+     * An array of supported "lib" reference file names used to determine the order for inclusion
+     * when referenced, as well as for spelling suggestions. This ensures the correct ordering for
+     * overload resolution when a type declared in one lib is extended by another.
+     */
+    const libs: string[];
+    /**
+     * A map of lib names to lib files. This map is used both for parsing the "lib" command line
+     * option as well as for resolving lib reference directives.
+     */
+    const libMap: Map<string>;
+    const optionDeclarations: CommandLineOption[];
+    const typeAcquisitionDeclarations: CommandLineOption[];
+    interface OptionNameMap {
+        optionNameMap: Map<CommandLineOption>;
+        shortOptionNames: Map<string>;
+    }
+    const defaultInitCompilerOptions: CompilerOptions;
+    function convertEnableAutoDiscoveryToEnable(typeAcquisition: TypeAcquisition): TypeAcquisition;
+    function createCompilerDiagnosticForInvalidCustomType(opt: CommandLineOptionOfCustomType): Diagnostic;
+    function parseCustomTypeOption(opt: CommandLineOptionOfCustomType, value: string, errors: Push<Diagnostic>): string | number | undefined;
+    function parseListTypeOption(opt: CommandLineOptionOfListType, value: string | undefined, errors: Push<Diagnostic>): (string | number)[] | undefined;
+    function parseCommandLine(commandLine: ReadonlyArray<string>, readFile?: (path: string) => string | undefined): ParsedCommandLine;
+    /** @internal */
+    function getOptionFromName(optionName: string, allowShort?: boolean): CommandLineOption | undefined;
+    function printVersion(): void;
+    function printHelp(optionsList: CommandLineOption[], syntaxPrefix?: string): void;
+    type DiagnosticReporter = (diagnostic: Diagnostic) => void;
+    /**
+     * Reports config file diagnostics
+     */
+    interface ConfigFileDiagnosticsReporter {
+        /**
+         * Reports unrecoverable error when parsing config file
+         */
+        onUnRecoverableConfigFileDiagnostic: DiagnosticReporter;
+    }
+    /**
+     * Interface extending ParseConfigHost to support ParseConfigFile that reads config file and reports errors
+     */
+    interface ParseConfigFileHost extends ParseConfigHost, ConfigFileDiagnosticsReporter {
+        getCurrentDirectory(): string;
+    }
+    /**
+     * Reads the config file, reports errors if any and exits if the config file cannot be found
+     */
+    function getParsedCommandLineOfConfigFile(configFileName: string, optionsToExtend: CompilerOptions, host: ParseConfigFileHost): ParsedCommandLine | undefined;
+    /**
+     * Read tsconfig.json file
+     * @param fileName The path to the config file
+     */
+    function readConfigFile(fileName: string, readFile: (path: string) => string | undefined): {
+        config?: any;
+        error?: Diagnostic;
+    };
+    /**
+     * Parse the text of the tsconfig.json file
+     * @param fileName The path to the config file
+     * @param jsonText The text of the config file
+     */
+    function parseConfigFileTextToJson(fileName: string, jsonText: string): {
+        config?: any;
+        error?: Diagnostic;
+    };
+    /**
+     * Read tsconfig.json file
+     * @param fileName The path to the config file
+     */
+    function readJsonConfigFile(fileName: string, readFile: (path: string) => string | undefined): TsConfigSourceFile;
+    interface JsonConversionNotifier {
+        /**
+         * Notifies parent option object is being set with the optionKey and a valid optionValue
+         * Currently it notifies only if there is element with type object (parentOption) and
+         * has element's option declarations map associated with it
+         * @param parentOption parent option name in which the option and value are being set
+         * @param option option declaration which is being set with the value
+         * @param value value of the option
+         */
+        onSetValidOptionKeyValueInParent(parentOption: string, option: CommandLineOption, value: CompilerOptionsValue): void;
+        /**
+         * Notify when valid root key value option is being set
+         * @param key option key
+         * @param keyNode node corresponding to node in the source file
+         * @param value computed value of the key
+         * @param ValueNode node corresponding to value in the source file
+         */
+        onSetValidOptionKeyValueInRoot(key: string, keyNode: PropertyName, value: CompilerOptionsValue, valueNode: Expression): void;
+        /**
+         * Notify when unknown root key value option is being set
+         * @param key option key
+         * @param keyNode node corresponding to node in the source file
+         * @param value computed value of the key
+         * @param ValueNode node corresponding to value in the source file
+         */
+        onSetUnknownOptionKeyValueInRoot(key: string, keyNode: PropertyName, value: CompilerOptionsValue, valueNode: Expression): void;
+    }
+    /**
+     * Convert the json syntax tree into the json value
+     */
+    function convertToObject(sourceFile: JsonSourceFile, errors: Push<Diagnostic>): any;
+    /**
+     * Convert the json syntax tree into the json value and report errors
+     * This returns the json value (apart from checking errors) only if returnValue provided is true.
+     * Otherwise it just checks the errors and returns undefined
+     */
+    function convertToObjectWorker(sourceFile: JsonSourceFile, errors: Push<Diagnostic>, returnValue: boolean, knownRootOptions: CommandLineOption | undefined, jsonConversionNotifier: JsonConversionNotifier | undefined): any;
+    /**
+     * Generate tsconfig configuration when running command line "--init"
+     * @param options commandlineOptions to be generated into tsconfig.json
+     * @param fileNames array of filenames to be generated into tsconfig.json
+     */
+    function generateTSConfig(options: CompilerOptions, fileNames: ReadonlyArray<string>, newLine: string): string;
+    /**
+     * Parse the contents of a config file (tsconfig.json).
+     * @param json The contents of the config file to parse
+     * @param host Instance of ParseConfigHost used to enumerate files in folder.
+     * @param basePath A root directory to resolve relative path entries in the config
+     *    file to. e.g. outDir
+     */
+    function parseJsonConfigFileContent(json: any, host: ParseConfigHost, basePath: string, existingOptions?: CompilerOptions, configFileName?: string, resolutionStack?: Path[], extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): ParsedCommandLine;
+    /**
+     * Parse the contents of a config file (tsconfig.json).
+     * @param jsonNode The contents of the config file to parse
+     * @param host Instance of ParseConfigHost used to enumerate files in folder.
+     * @param basePath A root directory to resolve relative path entries in the config
+     *    file to. e.g. outDir
+     */
+    function parseJsonSourceFileConfigFileContent(sourceFile: TsConfigSourceFile, host: ParseConfigHost, basePath: string, existingOptions?: CompilerOptions, configFileName?: string, resolutionStack?: Path[], extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): ParsedCommandLine;
+    function setConfigFileInOptions(options: CompilerOptions, configFile: TsConfigSourceFile | undefined): void;
+    function isErrorNoInputFiles(error: Diagnostic): boolean;
+    function getErrorForNoInputFiles({ includeSpecs, excludeSpecs }: ConfigFileSpecs, configFileName: string | undefined): Diagnostic;
+    function convertCompilerOptionsFromJson(jsonOptions: any, basePath: string, configFileName?: string): {
+        options: CompilerOptions;
+        errors: Diagnostic[];
+    };
+    function convertTypeAcquisitionFromJson(jsonOptions: any, basePath: string, configFileName?: string): {
+        options: TypeAcquisition;
+        errors: Diagnostic[];
+    };
+    /**
+     * Gets the file names from the provided config file specs that contain, files, include, exclude and
+     * other properties needed to resolve the file names
+     * @param spec The config file specs extracted with file names to include, wildcards to include/exclude and other details
+     * @param basePath The base path for any relative file specifications.
+     * @param options Compiler options.
+     * @param host The host used to resolve files and directories.
+     * @param extraFileExtensions optionaly file extra file extension information from host
+     */
+    function getFileNamesFromConfigSpecs(spec: ConfigFileSpecs, basePath: string, options: CompilerOptions, host: ParseConfigHost, extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): ExpandResult;
+    /**
+     * Produces a cleaned version of compiler options with personally identifiying info (aka, paths) removed.
+     * Also converts enum values back to strings.
+     */
+    function convertCompilerOptionsForTelemetry(opts: CompilerOptions): CompilerOptions;
+}
+declare namespace ts {
+    function trace(host: ModuleResolutionHost, message: DiagnosticMessage, ...args: any[]): void;
+    function isTraceEnabled(compilerOptions: CompilerOptions, host: ModuleResolutionHost): boolean;
+    /** Array that is only intended to be pushed to, never read. */
+    interface Push<T> {
+        push(value: T): void;
+    }
+    function readJson(path: string, host: {
+        readFile(fileName: string): string | undefined;
+    }): object;
     function getEffectiveTypeRoots(options: CompilerOptions, host: GetEffectiveTypeRootsHost): string[] | undefined;
     /**
      * @param {string | undefined} containingFile - file that contains type reference directive, can be undefined if containing file is unknown.
@@ -3520,13 +7603,78 @@ declare namespace ts {
         set(directory: string, result: ResolvedModuleWithFailedLookupLocations): void;
     }
     function createModuleResolutionCache(currentDirectory: string, getCanonicalFileName: (s: string) => string): ModuleResolutionCache;
+    function createModuleResolutionCacheWithMaps(directoryToModuleNameMap: Map<Map<ResolvedModuleWithFailedLookupLocations>>, moduleNameToDirectoryMap: Map<PerModuleNameCache>, currentDirectory: string, getCanonicalFileName: GetCanonicalFileName): ModuleResolutionCache;
     function resolveModuleNameFromCache(moduleName: string, containingFile: string, cache: ModuleResolutionCache): ResolvedModuleWithFailedLookupLocations | undefined;
     function resolveModuleName(moduleName: string, containingFile: string, compilerOptions: CompilerOptions, host: ModuleResolutionHost, cache?: ModuleResolutionCache): ResolvedModuleWithFailedLookupLocations;
     function nodeModuleNameResolver(moduleName: string, containingFile: string, compilerOptions: CompilerOptions, host: ModuleResolutionHost, cache?: ModuleResolutionCache): ResolvedModuleWithFailedLookupLocations;
+    /**
+     * Expose resolution logic to allow us to use Node module resolution logic from arbitrary locations.
+     * No way to do this with `require()`: https://github.com/nodejs/node/issues/5963
+     * Throws an error if the module can't be resolved.
+     */
+    function resolveJavaScriptModule(moduleName: string, initialDir: string, host: ModuleResolutionHost): string;
+    function directoryProbablyExists(directoryName: string, host: {
+        directoryExists?: (directoryName: string) => boolean;
+    }): boolean;
+    function getPackageName(moduleName: string): {
+        packageName: string;
+        rest: string;
+    };
+    function getTypesPackageName(packageName: string): string;
+    function getMangledNameForScopedPackage(packageName: string): string;
+    function getPackageNameFromAtTypesDirectory(mangledName: string): string;
+    function getUnmangledNameForScopedPackage(typesPackageName: string): string;
     function classicNameResolver(moduleName: string, containingFile: string, compilerOptions: CompilerOptions, host: ModuleResolutionHost, cache?: NonRelativeModuleNameResolutionCache): ResolvedModuleWithFailedLookupLocations;
+    /**
+     * LSHost may load a module from a global cache of typings.
+     * This is the minumum code needed to expose that functionality; the rest is in LSHost.
+     */
+    function loadModuleFromGlobalCache(moduleName: string, projectName: string | undefined, compilerOptions: CompilerOptions, host: ModuleResolutionHost, globalCache: string): ResolvedModuleWithFailedLookupLocations;
 }
 declare namespace ts {
+    enum ModuleInstanceState {
+        NonInstantiated = 0,
+        Instantiated = 1,
+        ConstEnumOnly = 2
+    }
+    function getModuleInstanceState(node: ModuleDeclaration): ModuleInstanceState;
+    function bindSourceFile(file: SourceFile, options: CompilerOptions): void;
+    function isExportsOrModuleExportsOrAlias(sourceFile: SourceFile, node: Expression): boolean;
+    /**
+     * Computes the transform flags for a node, given the transform flags of its subtree
+     *
+     * @param node The node to analyze
+     * @param subtreeFlags Transform flags computed for this node's subtree
+     */
+    function computeTransformFlagsForNode(node: Node, subtreeFlags: TransformFlags): TransformFlags;
+    /**
+     * Gets the transform flags to exclude when unioning the transform flags of a subtree.
+     *
+     * NOTE: This needs to be kept up-to-date with the exclusions used in `computeTransformFlagsForNode`.
+     *       For performance reasons, `computeTransformFlagsForNode` uses local constant values rather
+     *       than calling this function.
+     */
+    function getTransformFlagsSubtreeExclusions(kind: SyntaxKind): TransformFlags;
+}
+/** @internal */
+declare namespace ts {
+    function createGetSymbolWalker(getRestTypeOfSignature: (sig: Signature) => Type, getTypePredicateOfSignature: (sig: Signature) => TypePredicate | undefined, getReturnTypeOfSignature: (sig: Signature) => Type, getBaseTypes: (type: Type) => Type[], resolveStructuredTypeMembers: (type: ObjectType) => ResolvedType, getTypeOfSymbol: (sym: Symbol) => Type, getResolvedSymbol: (node: Node) => Symbol, getIndexTypeOfStructuredType: (type: Type, kind: IndexKind) => Type | undefined, getConstraintFromTypeParameter: (typeParameter: TypeParameter) => Type | undefined, getFirstIdentifier: (node: EntityNameOrEntityNameExpression) => Identifier): (accept?: (symbol: Symbol) => boolean) => SymbolWalker;
+}
+declare namespace ts {
+    function getNodeId(node: Node): number;
+    function getSymbolId(symbol: Symbol): number;
+    function isInstantiatedModule(node: ModuleDeclaration, preserveConstEnums: boolean): boolean;
+    function createTypeChecker(host: TypeCheckerHost, produceDiagnostics: boolean): TypeChecker;
+}
+declare namespace ts {
+    function updateNode<T extends Node>(updated: T, original: T): T;
+    function createNodeArray<T extends Node>(elements?: T[], hasTrailingComma?: boolean): MutableNodeArray<T>;
     function createNodeArray<T extends Node>(elements?: ReadonlyArray<T>, hasTrailingComma?: boolean): NodeArray<T>;
+    /**
+     * Creates a shallow, memberwise clone of a node with no source map location.
+     */
+    function getSynthesizedClone<T extends Node>(node: T): T;
+    function createLiteral(value: string | StringLiteral | NoSubstitutionTemplateLiteral | NumericLiteral | Identifier, isSingleQuote: boolean): StringLiteral;
     /** If a node is passed, creates a string literal whose source text is read from a source node during emit. */
     function createLiteral(value: string | StringLiteral | NoSubstitutionTemplateLiteral | NumericLiteral | Identifier): StringLiteral;
     function createLiteral(value: number): NumericLiteral;
@@ -3536,19 +7684,24 @@ declare namespace ts {
     function createStringLiteral(text: string): StringLiteral;
     function createRegularExpressionLiteral(text: string): RegularExpressionLiteral;
     function createIdentifier(text: string): Identifier;
+    function createIdentifier(text: string, typeArguments: ReadonlyArray<TypeNode | TypeParameterDeclaration> | undefined): Identifier;
     function updateIdentifier(node: Identifier): Identifier;
+    function updateIdentifier(node: Identifier, typeArguments: NodeArray<TypeNode | TypeParameterDeclaration> | undefined): Identifier;
     /** Create a unique temporary variable. */
     function createTempVariable(recordTempVariable: ((node: Identifier) => void) | undefined): Identifier;
+    function createTempVariable(recordTempVariable: ((node: Identifier) => void) | undefined, reservedInNestedScopes: boolean): GeneratedIdentifier;
     /** Create a unique temporary variable for use in a loop. */
     function createLoopVariable(): Identifier;
     /** Create a unique name based on the supplied text. */
     function createUniqueName(text: string): Identifier;
+    function createOptimisticUniqueName(text: string): GeneratedIdentifier;
     /** Create a unique name based on the supplied text. */
     function createOptimisticUniqueName(text: string): Identifier;
     /** Create a unique name based on the supplied text. This does not consider names injected by the transformer. */
     function createFileLevelUniqueName(text: string): Identifier;
     /** Create a unique name generated for a node. */
     function getGeneratedNameForNode(node: Node): Identifier;
+    function getGeneratedNameForNode(node: Node, flags: GeneratedIdentifierFlags): Identifier;
     function createToken<TKind extends SyntaxKind>(token: TKind): Token<TKind>;
     function createSuper(): SuperExpression;
     function createThis(): ThisExpression & Token<SyntaxKind.ThisKeyword>;
@@ -3587,6 +7740,7 @@ declare namespace ts {
     function updateConstructSignature(node: ConstructSignatureDeclaration, typeParameters: NodeArray<TypeParameterDeclaration> | undefined, parameters: NodeArray<ParameterDeclaration>, type: TypeNode | undefined): ConstructSignatureDeclaration;
     function createIndexSignature(decorators: ReadonlyArray<Decorator> | undefined, modifiers: ReadonlyArray<Modifier> | undefined, parameters: ReadonlyArray<ParameterDeclaration>, type: TypeNode): IndexSignatureDeclaration;
     function updateIndexSignature(node: IndexSignatureDeclaration, decorators: ReadonlyArray<Decorator> | undefined, modifiers: ReadonlyArray<Modifier> | undefined, parameters: ReadonlyArray<ParameterDeclaration>, type: TypeNode): IndexSignatureDeclaration;
+    function createSignatureDeclaration(kind: SyntaxKind, typeParameters: ReadonlyArray<TypeParameterDeclaration> | undefined, parameters: ReadonlyArray<ParameterDeclaration>, type: TypeNode | undefined, typeArguments?: ReadonlyArray<TypeNode> | undefined): SignatureDeclaration;
     function createKeywordTypeNode(kind: KeywordTypeNode["kind"]): KeywordTypeNode;
     function createTypePredicateNode(parameterName: Identifier | ThisTypeNode | string, type: TypeNode): TypePredicateNode;
     function updateTypePredicateNode(node: TypePredicateNode, parameterName: Identifier | ThisTypeNode, type: TypeNode): TypePredicateNode;
@@ -3647,6 +7801,8 @@ declare namespace ts {
     function updateNew(node: NewExpression, expression: Expression, typeArguments: ReadonlyArray<TypeNode> | undefined, argumentsArray: ReadonlyArray<Expression> | undefined): NewExpression;
     function createTaggedTemplate(tag: Expression, template: TemplateLiteral): TaggedTemplateExpression;
     function createTaggedTemplate(tag: Expression, typeArguments: ReadonlyArray<TypeNode> | undefined, template: TemplateLiteral): TaggedTemplateExpression;
+    /** @internal */
+    function createTaggedTemplate(tag: Expression, typeArgumentsOrTemplate: ReadonlyArray<TypeNode> | TemplateLiteral | undefined, template?: TemplateLiteral): TaggedTemplateExpression;
     function updateTaggedTemplate(node: TaggedTemplateExpression, tag: Expression, template: TemplateLiteral): TaggedTemplateExpression;
     function updateTaggedTemplate(node: TaggedTemplateExpression, tag: Expression, typeArguments: ReadonlyArray<TypeNode> | undefined, template: TemplateLiteral): TaggedTemplateExpression;
     function createTypeAssertion(type: TypeNode, expression: Expression): TypeAssertion;
@@ -3702,6 +7858,7 @@ declare namespace ts {
     function updateTemplateSpan(node: TemplateSpan, expression: Expression, literal: TemplateMiddle | TemplateTail): TemplateSpan;
     function createSemicolonClassElement(): SemicolonClassElement;
     function createBlock(statements: ReadonlyArray<Statement>, multiLine?: boolean): Block;
+    function createExpressionStatement(expression: Expression): ExpressionStatement;
     function updateBlock(node: Block, statements: ReadonlyArray<Statement>): Block;
     function createVariableStatement(modifiers: ReadonlyArray<Modifier> | undefined, declarationList: VariableDeclarationList | ReadonlyArray<VariableDeclaration>): VariableStatement;
     function updateVariableStatement(node: VariableStatement, modifiers: ReadonlyArray<Modifier> | undefined, declarationList: VariableDeclarationList): VariableStatement;
@@ -3827,6 +7984,16 @@ declare namespace ts {
      * @param original The original statement.
      */
     function createNotEmittedStatement(original: Node): NotEmittedStatement;
+    /**
+     * Creates a synthetic element to act as a placeholder for the end of an emitted declaration in
+     * order to properly emit exports.
+     */
+    function createEndOfDeclarationMarker(original: Node): EndOfDeclarationMarker;
+    /**
+     * Creates a synthetic element to act as a placeholder for the beginning of a merged declaration in
+     * order to properly emit exports.
+     */
+    function createMergeDeclarationMarker(original: Node): MergeDeclarationMarker;
     /**
      * Creates a synthetic expression to act as a placeholder for a not-emitted expression in
      * order to preserve comments or sourcemap positions.
@@ -3867,11 +8034,20 @@ declare namespace ts {
      * @param sourceFile A source file.
      */
     function disposeEmitNodes(sourceFile: SourceFile): void;
+    /**
+     * Associates a node with the current transformation, initializing
+     * various transient transformation properties.
+     */
+    function getOrCreateEmitNode(node: Node): EmitNode;
     function setTextRange<T extends TextRange>(range: T, location: TextRange | undefined): T;
     /**
      * Sets flags that control emit behavior of a node.
      */
     function setEmitFlags<T extends Node>(node: T, emitFlags: EmitFlags): T;
+    /**
+     * Sets flags that control emit behavior of a node.
+     */
+    function addEmitFlags<T extends Node>(node: T, emitFlags: EmitFlags): T;
     /**
      * Gets a custom text range to use when emitting source maps.
      */
@@ -3892,6 +8068,14 @@ declare namespace ts {
      * Sets the TextRange to use for source maps for a token of a node.
      */
     function setTokenSourceMapRange<T extends Node>(node: T, token: SyntaxKind, range: SourceMapRange | undefined): T;
+    /**
+     * Gets a custom text range to use when emitting comments.
+     */
+    function getStartsOnNewLine(node: Node): boolean | undefined;
+    /**
+     * Sets a custom text range to use when emitting comments.
+     */
+    function setStartsOnNewLine<T extends Node>(node: T, newLine: boolean): T;
     /**
      * Gets a custom text range to use when emitting comments.
      */
@@ -3935,8 +8119,262 @@ declare namespace ts {
      * Moves matching emit helpers from a source node to a target node.
      */
     function moveEmitHelpers(source: Node, target: Node, predicate: (helper: EmitHelper) => boolean): void;
+    function compareEmitHelpers(x: EmitHelper, y: EmitHelper): Comparison;
     function setOriginalNode<T extends Node>(node: T, original: Node | undefined): T;
 }
+declare namespace ts {
+    const nullTransformationContext: TransformationContext;
+    type TypeOfTag = "undefined" | "number" | "boolean" | "string" | "symbol" | "object" | "function";
+    function createTypeCheck(value: Expression, tag: TypeOfTag): BinaryExpression;
+    function createMemberAccessForPropertyName(target: Expression, memberName: PropertyName, location?: TextRange): MemberExpression;
+    function createFunctionCall(func: Expression, thisArg: Expression, argumentsList: ReadonlyArray<Expression>, location?: TextRange): CallExpression;
+    function createFunctionApply(func: Expression, thisArg: Expression, argumentsExpression: Expression, location?: TextRange): CallExpression;
+    function createArraySlice(array: Expression, start?: number | Expression): CallExpression;
+    function createArrayConcat(array: Expression, values: ReadonlyArray<Expression>): CallExpression;
+    function createMathPow(left: Expression, right: Expression, location?: TextRange): CallExpression;
+    function createExpressionForJsxElement(jsxFactoryEntity: EntityName | undefined, reactNamespace: string, tagName: Expression, props: Expression, children: ReadonlyArray<Expression>, parentElement: JsxOpeningLikeElement, location: TextRange): LeftHandSideExpression;
+    function createExpressionForJsxFragment(jsxFactoryEntity: EntityName | undefined, reactNamespace: string, children: ReadonlyArray<Expression>, parentElement: JsxOpeningFragment, location: TextRange): LeftHandSideExpression;
+    function getHelperName(name: string): Identifier;
+    function createValuesHelper(context: TransformationContext, expression: Expression, location?: TextRange): CallExpression;
+    function createReadHelper(context: TransformationContext, iteratorRecord: Expression, count: number | undefined, location?: TextRange): CallExpression;
+    function createSpreadHelper(context: TransformationContext, argumentList: ReadonlyArray<Expression>, location?: TextRange): CallExpression;
+    function createForOfBindingStatement(node: ForInitializer, boundValue: Expression): Statement;
+    function insertLeadingStatement(dest: Statement, source: Statement): Block;
+    function restoreEnclosingLabel(node: Statement, outermostLabeledStatement: LabeledStatement | undefined, afterRestoreLabelCallback?: (node: LabeledStatement) => void): Statement;
+    interface CallBinding {
+        target: LeftHandSideExpression;
+        thisArg: Expression;
+    }
+    function createCallBinding(expression: Expression, recordTempVariable: (temp: Identifier) => void, languageVersion?: ScriptTarget, cacheIdentifiers?: boolean): CallBinding;
+    function inlineExpressions(expressions: ReadonlyArray<Expression>): Expression;
+    function createExpressionFromEntityName(node: EntityName | Expression): Expression;
+    function createExpressionForPropertyName(memberName: PropertyName): Expression;
+    function createExpressionForObjectLiteralElementLike(node: ObjectLiteralExpression, property: ObjectLiteralElementLike, receiver: Expression): Expression | undefined;
+    /**
+     * Gets the internal name of a declaration. This is primarily used for declarations that can be
+     * referred to by name in the body of an ES5 class function body. An internal name will *never*
+     * be prefixed with an module or namespace export modifier like "exports." when emitted as an
+     * expression. An internal name will also *never* be renamed due to a collision with a block
+     * scoped variable.
+     *
+     * @param node The declaration.
+     * @param allowComments A value indicating whether comments may be emitted for the name.
+     * @param allowSourceMaps A value indicating whether source maps may be emitted for the name.
+     */
+    function getInternalName(node: Declaration, allowComments?: boolean, allowSourceMaps?: boolean): Identifier;
+    /**
+     * Gets whether an identifier should only be referred to by its internal name.
+     */
+    function isInternalName(node: Identifier): boolean;
+    /**
+     * Gets the local name of a declaration. This is primarily used for declarations that can be
+     * referred to by name in the declaration's immediate scope (classes, enums, namespaces). A
+     * local name will *never* be prefixed with an module or namespace export modifier like
+     * "exports." when emitted as an expression.
+     *
+     * @param node The declaration.
+     * @param allowComments A value indicating whether comments may be emitted for the name.
+     * @param allowSourceMaps A value indicating whether source maps may be emitted for the name.
+     */
+    function getLocalName(node: Declaration, allowComments?: boolean, allowSourceMaps?: boolean): Identifier;
+    /**
+     * Gets whether an identifier should only be referred to by its local name.
+     */
+    function isLocalName(node: Identifier): boolean;
+    /**
+     * Gets the export name of a declaration. This is primarily used for declarations that can be
+     * referred to by name in the declaration's immediate scope (classes, enums, namespaces). An
+     * export name will *always* be prefixed with an module or namespace export modifier like
+     * `"exports."` when emitted as an expression if the name points to an exported symbol.
+     *
+     * @param node The declaration.
+     * @param allowComments A value indicating whether comments may be emitted for the name.
+     * @param allowSourceMaps A value indicating whether source maps may be emitted for the name.
+     */
+    function getExportName(node: Declaration, allowComments?: boolean, allowSourceMaps?: boolean): Identifier;
+    /**
+     * Gets whether an identifier should only be referred to by its export representation if the
+     * name points to an exported symbol.
+     */
+    function isExportName(node: Identifier): boolean;
+    /**
+     * Gets the name of a declaration for use in declarations.
+     *
+     * @param node The declaration.
+     * @param allowComments A value indicating whether comments may be emitted for the name.
+     * @param allowSourceMaps A value indicating whether source maps may be emitted for the name.
+     */
+    function getDeclarationName(node: Declaration, allowComments?: boolean, allowSourceMaps?: boolean): Identifier;
+    /**
+     * Gets the exported name of a declaration for use in expressions.
+     *
+     * An exported name will *always* be prefixed with an module or namespace export modifier like
+     * "exports." if the name points to an exported symbol.
+     *
+     * @param ns The namespace identifier.
+     * @param node The declaration.
+     * @param allowComments A value indicating whether comments may be emitted for the name.
+     * @param allowSourceMaps A value indicating whether source maps may be emitted for the name.
+     */
+    function getExternalModuleOrNamespaceExportName(ns: Identifier | undefined, node: Declaration, allowComments?: boolean, allowSourceMaps?: boolean): Identifier | PropertyAccessExpression;
+    /**
+     * Gets a namespace-qualified name for use in expressions.
+     *
+     * @param ns The namespace identifier.
+     * @param name The name.
+     * @param allowComments A value indicating whether comments may be emitted for the name.
+     * @param allowSourceMaps A value indicating whether source maps may be emitted for the name.
+     */
+    function getNamespaceMemberName(ns: Identifier, name: Identifier, allowComments?: boolean, allowSourceMaps?: boolean): PropertyAccessExpression;
+    function convertToFunctionBody(node: ConciseBody, multiLine?: boolean): Block;
+    function convertFunctionDeclarationToExpression(node: FunctionDeclaration): FunctionExpression;
+    /**
+     * Add any necessary prologue-directives into target statement-array.
+     * The function needs to be called during each transformation step.
+     * This function needs to be called whenever we transform the statement
+     * list of a source file, namespace, or function-like body.
+     *
+     * @param target: result statements array
+     * @param source: origin statements array
+     * @param ensureUseStrict: boolean determining whether the function need to add prologue-directives
+     * @param visitor: Optional callback used to visit any custom prologue directives.
+     */
+    function addPrologue(target: Statement[], source: ReadonlyArray<Statement>, ensureUseStrict?: boolean, visitor?: (node: Node) => VisitResult<Node>): number;
+    /**
+     * Add just the standard (string-expression) prologue-directives into target statement-array.
+     * The function needs to be called during each transformation step.
+     * This function needs to be called whenever we transform the statement
+     * list of a source file, namespace, or function-like body.
+     */
+    function addStandardPrologue(target: Statement[], source: ReadonlyArray<Statement>, ensureUseStrict?: boolean): number;
+    /**
+     * Add just the custom prologue-directives into target statement-array.
+     * The function needs to be called during each transformation step.
+     * This function needs to be called whenever we transform the statement
+     * list of a source file, namespace, or function-like body.
+     */
+    function addCustomPrologue(target: Statement[], source: ReadonlyArray<Statement>, statementOffset: number, visitor?: (node: Node) => VisitResult<Node>): number;
+    function addCustomPrologue(target: Statement[], source: ReadonlyArray<Statement>, statementOffset: number | undefined, visitor?: (node: Node) => VisitResult<Node>): number | undefined;
+    function startsWithUseStrict(statements: ReadonlyArray<Statement>): boolean;
+    /**
+     * Ensures "use strict" directive is added
+     *
+     * @param statements An array of statements
+     */
+    function ensureUseStrict(statements: NodeArray<Statement>): NodeArray<Statement>;
+    /**
+     * Wraps the operand to a BinaryExpression in parentheses if they are needed to preserve the intended
+     * order of operations.
+     *
+     * @param binaryOperator The operator for the BinaryExpression.
+     * @param operand The operand for the BinaryExpression.
+     * @param isLeftSideOfBinary A value indicating whether the operand is the left side of the
+     *                           BinaryExpression.
+     */
+    function parenthesizeBinaryOperand(binaryOperator: SyntaxKind, operand: Expression, isLeftSideOfBinary: boolean, leftOperand?: Expression): Expression;
+    function parenthesizeForConditionalHead(condition: Expression): Expression;
+    function parenthesizeSubexpressionOfConditionalExpression(e: Expression): Expression;
+    /**
+     *  [Per the spec](https://tc39.github.io/ecma262/#prod-ExportDeclaration), `export default` accepts _AssigmentExpression_ but
+     *  has a lookahead restriction for `function`, `async function`, and `class`.
+     *
+     * Basically, that means we need to parenthesize in the following cases:
+     *
+     * - BinaryExpression of CommaToken
+     * - CommaList (synthetic list of multiple comma expressions)
+     * - FunctionExpression
+     * - ClassExpression
+     */
+    function parenthesizeDefaultExpression(e: Expression): Expression;
+    /**
+     * Wraps an expression in parentheses if it is needed in order to use the expression
+     * as the expression of a NewExpression node.
+     *
+     * @param expression The Expression node.
+     */
+    function parenthesizeForNew(expression: Expression): LeftHandSideExpression;
+    /**
+     * Wraps an expression in parentheses if it is needed in order to use the expression for
+     * property or element access.
+     *
+     * @param expr The expression node.
+     */
+    function parenthesizeForAccess(expression: Expression): LeftHandSideExpression;
+    function parenthesizePostfixOperand(operand: Expression): LeftHandSideExpression;
+    function parenthesizePrefixOperand(operand: Expression): UnaryExpression;
+    function parenthesizeListElements(elements: NodeArray<Expression>): NodeArray<Expression>;
+    function parenthesizeExpressionForList(expression: Expression): Expression;
+    function parenthesizeExpressionForExpressionStatement(expression: Expression): Expression;
+    function parenthesizeConditionalTypeMember(member: TypeNode): TypeNode;
+    function parenthesizeElementTypeMember(member: TypeNode): TypeNode;
+    function parenthesizeArrayTypeMember(member: TypeNode): TypeNode;
+    function parenthesizeElementTypeMembers(members: ReadonlyArray<TypeNode>): NodeArray<TypeNode>;
+    function parenthesizeTypeParameters(typeParameters: ReadonlyArray<TypeNode> | undefined): MutableNodeArray<TypeNode> | undefined;
+    function parenthesizeConciseBody(body: ConciseBody): ConciseBody;
+    enum OuterExpressionKinds {
+        Parentheses = 1,
+        Assertions = 2,
+        PartiallyEmittedExpressions = 4,
+        All = 7
+    }
+    type OuterExpression = ParenthesizedExpression | TypeAssertion | AsExpression | NonNullExpression | PartiallyEmittedExpression;
+    function isOuterExpression(node: Node, kinds?: OuterExpressionKinds): node is OuterExpression;
+    function skipOuterExpressions(node: Expression, kinds?: OuterExpressionKinds): Expression;
+    function skipOuterExpressions(node: Node, kinds?: OuterExpressionKinds): Node;
+    function skipAssertions(node: Expression): Expression;
+    function skipAssertions(node: Node): Node;
+    function recreateOuterExpressions(outerExpression: Expression | undefined, innerExpression: Expression, kinds?: OuterExpressionKinds): Expression;
+    function startOnNewLine<T extends Node>(node: T): T;
+    function getExternalHelpersModuleName(node: SourceFile): Identifier | undefined;
+    function getOrCreateExternalHelpersModuleNameIfNeeded(node: SourceFile, compilerOptions: CompilerOptions, hasExportStarsToExportValues?: boolean, hasImportStarOrImportDefault?: boolean): Identifier | undefined;
+    /**
+     * Get the name of that target module from an import or export declaration
+     */
+    function getLocalNameForExternalImport(node: ImportDeclaration | ExportDeclaration | ImportEqualsDeclaration, sourceFile: SourceFile): Identifier | undefined;
+    /**
+     * Get the name of a target module from an import/export declaration as should be written in the emitted output.
+     * The emitted output name can be different from the input if:
+     *  1. The module has a /// <amd-module name="<new name>" />
+     *  2. --out or --outFile is used, making the name relative to the rootDir
+     *  3- The containing SourceFile has an entry in renamedDependencies for the import as requested by some module loaders (e.g. System).
+     * Otherwise, a new StringLiteral node representing the module name will be returned.
+     */
+    function getExternalModuleNameLiteral(importNode: ImportDeclaration | ExportDeclaration | ImportEqualsDeclaration, sourceFile: SourceFile, host: EmitHost, resolver: EmitResolver, compilerOptions: CompilerOptions): StringLiteral | undefined;
+    /**
+     * Get the name of a module as should be written in the emitted output.
+     * The emitted output name can be different from the input if:
+     *  1. The module has a /// <amd-module name="<new name>" />
+     *  2. --out or --outFile is used, making the name relative to the rootDir
+     * Otherwise, a new StringLiteral node representing the module name will be returned.
+     */
+    function tryGetModuleNameFromFile(file: SourceFile | undefined, host: EmitHost, options: CompilerOptions): StringLiteral | undefined;
+    /**
+     * Gets the initializer of an BindingOrAssignmentElement.
+     */
+    function getInitializerOfBindingOrAssignmentElement(bindingElement: BindingOrAssignmentElement): Expression | undefined;
+    /**
+     * Gets the name of an BindingOrAssignmentElement.
+     */
+    function getTargetOfBindingOrAssignmentElement(bindingElement: BindingOrAssignmentElement): BindingOrAssignmentElementTarget | undefined;
+    /**
+     * Determines whether an BindingOrAssignmentElement is a rest element.
+     */
+    function getRestIndicatorOfBindingOrAssignmentElement(bindingElement: BindingOrAssignmentElement): BindingOrAssignmentElementRestIndicator | undefined;
+    /**
+     * Gets the property name of a BindingOrAssignmentElement
+     */
+    function getPropertyNameOfBindingOrAssignmentElement(bindingElement: BindingOrAssignmentElement): Identifier | StringLiteral | NumericLiteral | ComputedPropertyName | undefined;
+    /**
+     * Gets the elements of a BindingOrAssignmentPattern
+     */
+    function getElementsOfBindingOrAssignmentPattern(name: BindingOrAssignmentPattern): ReadonlyArray<BindingOrAssignmentElement>;
+    function convertToArrayAssignmentElement(element: BindingOrAssignmentElement): Expression;
+    function convertToObjectAssignmentElement(element: BindingOrAssignmentElement): ObjectLiteralElementLike;
+    function convertToAssignmentPattern(node: BindingOrAssignmentPattern): AssignmentPattern;
+    function convertToObjectAssignmentPattern(node: ObjectBindingOrAssignmentPattern): ObjectLiteralExpression;
+    function convertToArrayAssignmentPattern(node: ArrayBindingOrAssignmentPattern): ArrayLiteralExpression;
+    function convertToAssignmentElementTarget(node: BindingOrAssignmentElementTarget): Expression;
+}
 declare namespace ts {
     /**
      * Visits a Node using the supplied visitor, possibly returning a new Node in its place.
@@ -4019,11 +8457,357 @@ declare namespace ts {
     function visitEachChild<T extends Node>(node: T | undefined, visitor: Visitor, context: TransformationContext, nodesVisitor?: typeof visitNodes, tokenVisitor?: Visitor): T | undefined;
 }
 declare namespace ts {
+    /**
+     * Similar to `reduceLeft`, performs a reduction against each child of a node.
+     * NOTE: Unlike `forEachChild`, this does *not* visit every node.
+     *
+     * @param node The node containing the children to reduce.
+     * @param initial The initial value to supply to the reduction.
+     * @param f The callback function
+     */
+    function reduceEachChild<T>(node: Node | undefined, initial: T, cbNode: (memo: T, node: Node) => T, cbNodeArray?: (memo: T, nodes: NodeArray<Node>) => T): T;
+    /**
+     * Merges generated lexical declarations into a new statement list.
+     */
+    function mergeLexicalEnvironment(statements: NodeArray<Statement>, declarations: ReadonlyArray<Statement> | undefined): NodeArray<Statement>;
+    /**
+     * Appends generated lexical declarations to an array of statements.
+     */
+    function mergeLexicalEnvironment(statements: Statement[], declarations: ReadonlyArray<Statement> | undefined): Statement[];
+    /**
+     * Lifts a NodeArray containing only Statement nodes to a block.
+     *
+     * @param nodes The NodeArray.
+     */
+    function liftToBlock(nodes: ReadonlyArray<Node>): Statement;
+    /**
+     * Aggregates the TransformFlags for a Node and its subtree.
+     */
+    function aggregateTransformFlags<T extends Node>(node: T): T;
+    namespace Debug {
+        function failBadSyntaxKind(node: Node, message?: string): never;
+        const assertEachNode: (nodes: Node[], test: (node: Node) => boolean, message?: string | undefined) => void;
+        const assertNode: (node: Node | undefined, test: ((node: Node | undefined) => boolean) | undefined, message?: string | undefined) => void;
+        const assertOptionalNode: (node: Node, test: (node: Node) => boolean, message?: string | undefined) => void;
+        const assertOptionalToken: (node: Node, kind: SyntaxKind, message?: string | undefined) => void;
+        const assertMissingNode: typeof noop;
+        /**
+         * Injects debug information into frequently used types.
+         */
+        function enableDebugInfo(): void;
+    }
+}
+declare namespace ts {
+    function getOriginalNodeId(node: Node): number;
+    interface ExternalModuleInfo {
+        externalImports: (ImportDeclaration | ImportEqualsDeclaration | ExportDeclaration)[];
+        externalHelpersImportDeclaration: ImportDeclaration | undefined;
+        exportSpecifiers: Map<ExportSpecifier[]>;
+        exportedBindings: Identifier[][];
+        exportedNames: Identifier[] | undefined;
+        exportEquals: ExportAssignment | undefined;
+        hasExportStarsToExportValues: boolean;
+    }
+    function chainBundle(transformSourceFile: (x: SourceFile) => SourceFile): (x: SourceFile | Bundle) => SourceFile | Bundle;
+    function getImportNeedsImportStarHelper(node: ImportDeclaration): boolean;
+    function getImportNeedsImportDefaultHelper(node: ImportDeclaration): boolean;
+    function collectExternalModuleInfo(sourceFile: SourceFile, resolver: EmitResolver, compilerOptions: CompilerOptions): ExternalModuleInfo;
+    /**
+     * Used in the module transformer to check if an expression is reasonably without sideeffect,
+     *  and thus better to copy into multiple places rather than to cache in a temporary variable
+     *  - this is mostly subjective beyond the requirement that the expression not be sideeffecting
+     */
+    function isSimpleCopiableExpression(expression: Expression): boolean;
+    /**
+     * @param input Template string input strings
+     * @param args Names which need to be made file-level unique
+     */
+    function helperString(input: TemplateStringsArray, ...args: string[]): (uniqueName: EmitHelperUniqueNameCallback) => string;
+}
+declare namespace ts {
+    enum FlattenLevel {
+        All = 0,
+        ObjectRest = 1
+    }
+    /**
+     * Flattens a DestructuringAssignment or a VariableDeclaration to an expression.
+     *
+     * @param node The node to flatten.
+     * @param visitor An optional visitor used to visit initializers.
+     * @param context The transformation context.
+     * @param level Indicates the extent to which flattening should occur.
+     * @param needsValue An optional value indicating whether the value from the right-hand-side of
+     * the destructuring assignment is needed as part of a larger expression.
+     * @param createAssignmentCallback An optional callback used to create the assignment expression.
+     */
+    function flattenDestructuringAssignment(node: VariableDeclaration | DestructuringAssignment, visitor: ((node: Node) => VisitResult<Node>) | undefined, context: TransformationContext, level: FlattenLevel, needsValue?: boolean, createAssignmentCallback?: (name: Identifier, value: Expression, location?: TextRange) => Expression): Expression;
+    /**
+     * Flattens a VariableDeclaration or ParameterDeclaration to one or more variable declarations.
+     *
+     * @param node The node to flatten.
+     * @param visitor An optional visitor used to visit initializers.
+     * @param context The transformation context.
+     * @param boundValue The value bound to the declaration.
+     * @param skipInitializer A value indicating whether to ignore the initializer of `node`.
+     * @param hoistTempVariables Indicates whether temporary variables should not be recorded in-line.
+     * @param level Indicates the extent to which flattening should occur.
+     */
+    function flattenDestructuringBinding(node: VariableDeclaration | ParameterDeclaration, visitor: (node: Node) => VisitResult<Node>, context: TransformationContext, level: FlattenLevel, rval?: Expression, hoistTempVariables?: boolean, skipInitializer?: boolean): VariableDeclaration[];
+}
+declare namespace ts {
+    function transformTypeScript(context: TransformationContext): (node: SourceFile | Bundle) => SourceFile | Bundle;
+}
+declare namespace ts {
+    function transformES2017(context: TransformationContext): (x: SourceFile | Bundle) => SourceFile | Bundle;
+    const asyncSuperHelper: EmitHelper;
+    const advancedAsyncSuperHelper: EmitHelper;
+}
+declare namespace ts {
+    function transformESNext(context: TransformationContext): (x: SourceFile | Bundle) => SourceFile | Bundle;
+    function createAssignHelper(context: TransformationContext, attributesSegments: Expression[]): CallExpression;
+}
+declare namespace ts {
+    function transformJsx(context: TransformationContext): (x: SourceFile | Bundle) => SourceFile | Bundle;
+}
+declare namespace ts {
+    function transformES2016(context: TransformationContext): (x: SourceFile | Bundle) => SourceFile | Bundle;
+}
+declare namespace ts {
+    function transformES2015(context: TransformationContext): (x: SourceFile | Bundle) => SourceFile | Bundle;
+}
+declare namespace ts {
+    /**
+     * Transforms ES5 syntax into ES3 syntax.
+     *
+     * @param context Context and state information for the transformation.
+     */
+    function transformES5(context: TransformationContext): (x: SourceFile | Bundle) => SourceFile | Bundle;
+}
+declare namespace ts {
+    function transformGenerators(context: TransformationContext): (x: SourceFile | Bundle) => SourceFile | Bundle;
+}
+declare namespace ts {
+    function transformModule(context: TransformationContext): (x: SourceFile | Bundle) => SourceFile | Bundle;
+}
+declare namespace ts {
+    function transformSystemModule(context: TransformationContext): (x: SourceFile | Bundle) => SourceFile | Bundle;
+}
+declare namespace ts {
+    function transformES2015Module(context: TransformationContext): (x: SourceFile | Bundle) => SourceFile | Bundle;
+}
+declare namespace ts {
+    type GetSymbolAccessibilityDiagnostic = (symbolAccessibilityResult: SymbolAccessibilityResult) => (SymbolAccessibilityDiagnostic | undefined);
+    interface SymbolAccessibilityDiagnostic {
+        errorNode: Node;
+        diagnosticMessage: DiagnosticMessage;
+        typeName?: DeclarationName | QualifiedName;
+    }
+    type DeclarationDiagnosticProducing = VariableDeclaration | PropertyDeclaration | PropertySignature | BindingElement | SetAccessorDeclaration | GetAccessorDeclaration | ConstructSignatureDeclaration | CallSignatureDeclaration | MethodDeclaration | MethodSignature | FunctionDeclaration | ParameterDeclaration | TypeParameterDeclaration | ExpressionWithTypeArguments | ImportEqualsDeclaration | TypeAliasDeclaration | ConstructorDeclaration | IndexSignatureDeclaration;
+    function canProduceDiagnostics(node: Node): node is DeclarationDiagnosticProducing;
+    function createGetSymbolAccessibilityDiagnosticForNodeName(node: DeclarationDiagnosticProducing): (symbolAccessibilityResult: SymbolAccessibilityResult) => SymbolAccessibilityDiagnostic | undefined;
+    function createGetSymbolAccessibilityDiagnosticForNode(node: DeclarationDiagnosticProducing): (symbolAccessibilityResult: SymbolAccessibilityResult) => SymbolAccessibilityDiagnostic | undefined;
+}
+declare namespace ts {
+    function getDeclarationDiagnostics(host: EmitHost, resolver: EmitResolver, file: SourceFile | undefined): DiagnosticWithLocation[] | undefined;
+    /**
+     * Transforms a ts file into a .d.ts file
+     * This process requires type information, which is retrieved through the emit resolver. Because of this,
+     * in many places this transformer assumes it will be operating on parse tree nodes directly.
+     * This means that _no transforms should be allowed to occur before this one_.
+     */
+    function transformDeclarations(context: TransformationContext): {
+        (node: Bundle): Bundle;
+        (node: SourceFile): SourceFile;
+        (node: SourceFile | Bundle): SourceFile | Bundle;
+    };
+}
+declare namespace ts {
+    function getTransformers(compilerOptions: CompilerOptions, customTransformers?: CustomTransformers): TransformerFactory<SourceFile | Bundle>[];
+    /**
+     * Transforms an array of SourceFiles by passing them through each transformer.
+     *
+     * @param resolver The emit resolver provided by the checker.
+     * @param host The emit host object used to interact with the file system.
+     * @param options Compiler options to surface in the `TransformationContext`.
+     * @param nodes An array of nodes to transform.
+     * @param transforms An array of `TransformerFactory` callbacks.
+     * @param allowDtsFiles A value indicating whether to allow the transformation of .d.ts files.
+     */
+    function transformNodes<T extends Node>(resolver: EmitResolver | undefined, host: EmitHost | undefined, options: CompilerOptions, nodes: ReadonlyArray<T>, transformers: ReadonlyArray<TransformerFactory<T>>, allowDtsFiles: boolean): TransformationResult<T>;
+}
+declare namespace ts {
+    interface SourceMapWriter {
+        /**
+         * Initialize the SourceMapWriter for a new output file.
+         *
+         * @param filePath The path to the generated output file.
+         * @param sourceMapFilePath The path to the output source map file.
+         * @param sourceFileOrBundle The input source file or bundle for the program.
+         */
+        initialize(filePath: string, sourceMapFilePath: string | undefined, sourceFileOrBundle: SourceFile | Bundle, sourceMapOutput?: SourceMapData[]): void;
+        /**
+         * Reset the SourceMapWriter to an empty state.
+         */
+        reset(): void;
+        /**
+         * Set the current source file.
+         *
+         * @param sourceFile The source file.
+         */
+        setSourceFile(sourceFile: SourceMapSource): void;
+        /**
+         * Emits a mapping.
+         *
+         * If the position is synthetic (undefined or a negative value), no mapping will be
+         * created.
+         *
+         * @param pos The position.
+         */
+        emitPos(pos: number): void;
+        /**
+         * Emits a node with possible leading and trailing source maps.
+         *
+         * @param hint The current emit context
+         * @param node The node to emit.
+         * @param emitCallback The callback used to emit the node.
+         */
+        emitNodeWithSourceMap(hint: EmitHint, node: Node, emitCallback: (hint: EmitHint, node: Node) => void): void;
+        /**
+         * Emits a token of a node node with possible leading and trailing source maps.
+         *
+         * @param node The node containing the token.
+         * @param token The token to emit.
+         * @param tokenStartPos The start pos of the token.
+         * @param emitCallback The callback used to emit the token.
+         */
+        emitTokenWithSourceMap(node: Node, token: SyntaxKind, writer: (s: string) => void, tokenStartPos: number, emitCallback: (token: SyntaxKind, writer: (s: string) => void, tokenStartPos: number) => number): number;
+        /**
+         * Gets the text for the source map.
+         */
+        getText(): string;
+        /**
+         * Gets the SourceMappingURL for the source map.
+         */
+        getSourceMappingURL(): string;
+    }
+    interface SourceMapOptions {
+        sourceMap?: boolean;
+        inlineSourceMap?: boolean;
+        inlineSources?: boolean;
+        sourceRoot?: string;
+        mapRoot?: string;
+        extendedDiagnostics?: boolean;
+    }
+    function createSourceMapWriter(host: EmitHost, writer: EmitTextWriter, compilerOptions?: SourceMapOptions): SourceMapWriter;
+}
+declare namespace ts {
+    interface CommentWriter {
+        reset(): void;
+        setSourceFile(sourceFile: SourceFile): void;
+        setWriter(writer: EmitTextWriter | undefined): void;
+        emitNodeWithComments(hint: EmitHint, node: Node | undefined, emitCallback: (hint: EmitHint, node: Node) => void): void;
+        emitBodyWithDetachedComments(node: Node, detachedRange: TextRange, emitCallback: (node: Node) => void): void;
+        emitTrailingCommentsOfPosition(pos: number, prefixSpace?: boolean): void;
+        emitLeadingCommentsOfPosition(pos: number): void;
+    }
+    function createCommentWriter(printerOptions: PrinterOptions, emitPos: ((pos: number) => void) | undefined): CommentWriter;
+}
+declare namespace ts {
+    /**
+     * Iterates over the source files that are expected to have an emit output.
+     *
+     * @param host An EmitHost.
+     * @param action The action to execute.
+     * @param sourceFilesOrTargetSourceFile
+     *   If an array, the full list of source files to emit.
+     *   Else, calls `getSourceFilesToEmit` with the (optional) target source file to determine the list of source files to emit.
+     */
+    function forEachEmittedFile<T>(host: EmitHost, action: (emitFileNames: EmitFileNames, sourceFileOrBundle: SourceFile | Bundle) => T, sourceFilesOrTargetSourceFile?: ReadonlyArray<SourceFile> | SourceFile, emitOnlyDtsFiles?: boolean): T | undefined;
+    function getOutputPathsFor(sourceFile: SourceFile | Bundle, host: EmitHost, forceDtsPaths: boolean): EmitFileNames;
+    function getOutputExtension(sourceFile: SourceFile, options: CompilerOptions): Extension;
+    function emitFiles(resolver: EmitResolver, host: EmitHost, targetSourceFile: SourceFile, emitOnlyDtsFiles?: boolean, transformers?: TransformerFactory<Bundle | SourceFile>[], declarationTransformers?: TransformerFactory<Bundle | SourceFile>[]): EmitResult;
     function createPrinter(printerOptions?: PrinterOptions, handlers?: PrintHandlers): Printer;
 }
+declare namespace ts {
+    /**
+     * Partial interface of the System thats needed to support the caching of directory structure
+     */
+    interface DirectoryStructureHost {
+        fileExists(path: string): boolean;
+        readFile(path: string, encoding?: string): string | undefined;
+        directoryExists?(path: string): boolean;
+        getDirectories?(path: string): string[];
+        readDirectory?(path: string, extensions?: ReadonlyArray<string>, exclude?: ReadonlyArray<string>, include?: ReadonlyArray<string>, depth?: number): string[];
+        createDirectory?(path: string): void;
+        writeFile?(path: string, data: string, writeByteOrderMark?: boolean): void;
+    }
+    interface FileAndDirectoryExistence {
+        fileExists: boolean;
+        directoryExists: boolean;
+    }
+    interface CachedDirectoryStructureHost extends DirectoryStructureHost {
+        useCaseSensitiveFileNames: boolean;
+        getDirectories(path: string): string[];
+        readDirectory(path: string, extensions?: ReadonlyArray<string>, exclude?: ReadonlyArray<string>, include?: ReadonlyArray<string>, depth?: number): string[];
+        /** Returns the queried result for the file exists and directory exists if at all it was done */
+        addOrDeleteFileOrDirectory(fileOrDirectory: string, fileOrDirectoryPath: Path): FileAndDirectoryExistence | undefined;
+        addOrDeleteFile(fileName: string, filePath: Path, eventKind: FileWatcherEventKind): void;
+        clearCache(): void;
+    }
+    function createCachedDirectoryStructureHost(host: DirectoryStructureHost, currentDirectory: string, useCaseSensitiveFileNames: boolean): CachedDirectoryStructureHost | undefined;
+    enum ConfigFileProgramReloadLevel {
+        None = 0,
+        /** Update the file name list from the disk */
+        Partial = 1,
+        /** Reload completely by re-reading contents of config file from disk and updating program */
+        Full = 2
+    }
+    /**
+     * Updates the existing missing file watches with the new set of missing files after new program is created
+     */
+    function updateMissingFilePathsWatch(program: Program, missingFileWatches: Map<FileWatcher>, createMissingFileWatch: (missingFilePath: Path) => FileWatcher): void;
+    interface WildcardDirectoryWatcher {
+        watcher: FileWatcher;
+        flags: WatchDirectoryFlags;
+    }
+    /**
+     * Updates the existing wild card directory watches with the new set of wild card directories from the config file
+     * after new program is created because the config file was reloaded or program was created first time from the config file
+     * Note that there is no need to call this function when the program is updated with additional files without reloading config files,
+     * as wildcard directories wont change unless reloading config file
+     */
+    function updateWatchingWildcardDirectories(existingWatchedForWildcards: Map<WildcardDirectoryWatcher>, wildcardDirectories: Map<WatchDirectoryFlags>, watchDirectory: (directory: string, flags: WatchDirectoryFlags) => FileWatcher): void;
+    function isEmittedFileOfProgram(program: Program | undefined, file: string): boolean;
+    enum WatchLogLevel {
+        None = 0,
+        TriggerOnly = 1,
+        Verbose = 2
+    }
+    interface WatchFileHost {
+        watchFile(path: string, callback: FileWatcherCallback, pollingInterval?: number): FileWatcher;
+    }
+    interface WatchDirectoryHost {
+        watchDirectory(path: string, callback: DirectoryWatcherCallback, recursive?: boolean): FileWatcher;
+    }
+    type WatchFile<X, Y> = (host: WatchFileHost, file: string, callback: FileWatcherCallback, pollingInterval: PollingInterval, detailInfo1?: X, detailInfo2?: Y) => FileWatcher;
+    type FilePathWatcherCallback = (fileName: string, eventKind: FileWatcherEventKind, filePath: Path) => void;
+    type WatchFilePath<X, Y> = (host: WatchFileHost, file: string, callback: FilePathWatcherCallback, pollingInterval: PollingInterval, path: Path, detailInfo1?: X, detailInfo2?: Y) => FileWatcher;
+    type WatchDirectory<X, Y> = (host: WatchDirectoryHost, directory: string, callback: DirectoryWatcherCallback, flags: WatchDirectoryFlags, detailInfo1?: X, detailInfo2?: Y) => FileWatcher;
+    interface WatchFactory<X, Y> {
+        watchFile: WatchFile<X, Y>;
+        watchFilePath: WatchFilePath<X, Y>;
+        watchDirectory: WatchDirectory<X, Y>;
+    }
+    function getWatchFactory<X, Y = undefined>(watchLogLevel: WatchLogLevel, log: (s: string) => void, getDetailWatchInfo?: GetDetailWatchInfo<X, Y>): WatchFactory<X, Y>;
+    type GetDetailWatchInfo<X, Y> = (detailInfo1: X, detailInfo2: Y | undefined) => string;
+    function closeFileWatcherOf<T extends {
+        watcher: FileWatcher;
+    }>(objWithWatcher: T): void;
+}
 declare namespace ts {
     function findConfigFile(searchPath: string, fileExists: (fileName: string) => boolean, configName?: string): string | undefined;
     function resolveTripleslashReference(moduleName: string, containingFile: string): string;
+    function computeCommonSourceDirectoryOfFilenames(fileNames: string[], currentDirectory: string, getCanonicalFileName: GetCanonicalFileName): string;
     function createCompilerHost(options: CompilerOptions, setParentNodes?: boolean): CompilerHost;
     function getPreEmitDiagnostics(program: Program, sourceFile?: SourceFile, cancellationToken?: CancellationToken): Diagnostic[];
     interface FormatDiagnosticsHost {
@@ -4033,8 +8817,22 @@ declare namespace ts {
     }
     function formatDiagnostics(diagnostics: ReadonlyArray<Diagnostic>, host: FormatDiagnosticsHost): string;
     function formatDiagnostic(diagnostic: Diagnostic, host: FormatDiagnosticsHost): string;
+    /** @internal */
+    enum ForegroundColorEscapeSequences {
+        Grey = "\u001B[90m",
+        Red = "\u001B[91m",
+        Yellow = "\u001B[93m",
+        Blue = "\u001B[94m",
+        Cyan = "\u001B[96m"
+    }
+    /** @internal */
+    function formatColorAndReset(text: string, formatStyle: string): string;
     function formatDiagnosticsWithColorAndContext(diagnostics: ReadonlyArray<Diagnostic>, host: FormatDiagnosticsHost): string;
     function flattenDiagnosticMessageText(messageText: string | DiagnosticMessageChain | undefined, newLine: string): string;
+    /**
+     * Determines if program structure is upto date or needs to be recreated
+     */
+    function isProgramUptoDate(program: Program | undefined, rootFileNames: string[], newOptions: CompilerOptions, getSourceVersion: (path: Path) => string | undefined, fileExists: (fileName: string) => boolean, hasInvalidatedResolution: HasInvalidatedResolution, hasChangedAutomaticTypeDirectiveNames: boolean): boolean;
     function getConfigFileParsingDiagnostics(configFileParseResult: ParsedCommandLine): ReadonlyArray<Diagnostic>;
     /**
      * Create a new 'Program' instance. A Program is an immutable collection of 'SourceFile's and a 'CompilerOptions'
@@ -4062,10 +8860,17 @@ declare namespace ts {
      * @returns A 'Program' object.
      */
     function createProgram(rootNames: ReadonlyArray<string>, options: CompilerOptions, host?: CompilerHost, oldProgram?: Program, configFileParsingDiagnostics?: ReadonlyArray<Diagnostic>): Program;
+    function parseConfigHostFromCompilerHost(host: CompilerHost): ParseConfigFileHost;
     /**
      * Returns the target config filename of a project reference
      */
     function resolveProjectReferencePath(host: CompilerHost, ref: ProjectReference): string | undefined;
+    /**
+     * Returns a DiagnosticMessage if we won't include a resolved module due to its extension.
+     * The DiagnosticMessage's parameters are the imported module name, and the filename it resolved to.
+     * This returns a diagnostic even if the module will be an untyped module.
+     */
+    function getResolutionDiagnostic(options: CompilerOptions, { extension }: ResolvedModuleFull): DiagnosticMessage | undefined;
 }
 declare namespace ts {
     interface EmitOutput {
@@ -4078,6 +8883,126 @@ declare namespace ts {
         text: string;
     }
 }
+declare namespace ts {
+    function getFileEmitOutput(program: Program, sourceFile: SourceFile, emitOnlyDtsFiles: boolean, cancellationToken?: CancellationToken, customTransformers?: CustomTransformers): EmitOutput;
+    interface BuilderState {
+        /**
+         * Information of the file eg. its version, signature etc
+         */
+        fileInfos: Map<BuilderState.FileInfo>;
+        /**
+         * Contains the map of ReferencedSet=Referenced files of the file if module emit is enabled
+         * Otherwise undefined
+         * Thus non undefined value indicates, module emit
+         */
+        readonly referencedMap: ReadonlyMap<BuilderState.ReferencedSet> | undefined;
+        /**
+         * Map of files that have already called update signature.
+         * That means hence forth these files are assumed to have
+         * no change in their signature for this version of the program
+         */
+        hasCalledUpdateShapeSignature: Map<true>;
+        /**
+         * Cache of all files excluding default library file for the current program
+         */
+        allFilesExcludingDefaultLibraryFile: ReadonlyArray<SourceFile> | undefined;
+        /**
+         * Cache of all the file names
+         */
+        allFileNames: ReadonlyArray<string> | undefined;
+    }
+}
+declare namespace ts.BuilderState {
+    /**
+     * Information about the source file: Its version and optional signature from last emit
+     */
+    interface FileInfo {
+        readonly version: string;
+        signature: string | undefined;
+    }
+    /**
+     * Referenced files with values for the keys as referenced file's path to be true
+     */
+    type ReferencedSet = ReadonlyMap<true>;
+    /**
+     * Compute the hash to store the shape of the file
+     */
+    type ComputeHash = (data: string) => string;
+    /**
+     * Returns true if oldState is reusable, that is the emitKind = module/non module has not changed
+     */
+    function canReuseOldState(newReferencedMap: ReadonlyMap<ReferencedSet> | undefined, oldState: Readonly<BuilderState> | undefined): boolean | undefined;
+    /**
+     * Creates the state of file references and signature for the new program from oldState if it is safe
+     */
+    function create(newProgram: Program, getCanonicalFileName: GetCanonicalFileName, oldState?: Readonly<BuilderState>): BuilderState;
+    /**
+     * Gets the files affected by the path from the program
+     */
+    function getFilesAffectedBy(state: BuilderState, programOfThisState: Program, path: Path, cancellationToken: CancellationToken | undefined, computeHash: ComputeHash, cacheToUpdateSignature?: Map<string>): ReadonlyArray<SourceFile>;
+    /**
+     * Updates the signatures from the cache into state's fileinfo signatures
+     * This should be called whenever it is safe to commit the state of the builder
+     */
+    function updateSignaturesFromCache(state: BuilderState, signatureCache: Map<string>): void;
+    /**
+     * Get all the dependencies of the sourceFile
+     */
+    function getAllDependencies(state: BuilderState, programOfThisState: Program, sourceFile: SourceFile): ReadonlyArray<string>;
+}
+declare namespace ts {
+    /**
+     * State to store the changed files, affected files and cache semantic diagnostics
+     */
+    interface BuilderProgramState extends BuilderState {
+        /**
+         * Cache of semantic diagnostics for files with their Path being the key
+         */
+        semanticDiagnosticsPerFile: Map<ReadonlyArray<Diagnostic>> | undefined;
+        /**
+         * The map has key by source file's path that has been changed
+         */
+        changedFilesSet: Map<true>;
+        /**
+         * Set of affected files being iterated
+         */
+        affectedFiles: ReadonlyArray<SourceFile> | undefined;
+        /**
+         * Current index to retrieve affected file from
+         */
+        affectedFilesIndex: number | undefined;
+        /**
+         * Current changed file for iterating over affected files
+         */
+        currentChangedFilePath: Path | undefined;
+        /**
+         * Map of file signatures, with key being file path, calculated while getting current changed file's affected files
+         * These will be commited whenever the iteration through affected files of current changed file is complete
+         */
+        currentAffectedFilesSignatures: Map<string> | undefined;
+        /**
+         * Already seen affected files
+         */
+        seenAffectedFiles: Map<true> | undefined;
+        /**
+         * program corresponding to this state
+         */
+        program: Program;
+    }
+    enum BuilderProgramKind {
+        SemanticDiagnosticsBuilderProgram = 0,
+        EmitAndSemanticDiagnosticsBuilderProgram = 1
+    }
+    interface BuilderCreationParameters {
+        newProgram: Program;
+        host: BuilderProgramHost;
+        oldProgram: BuilderProgram | undefined;
+        configFileParsingDiagnostics: ReadonlyArray<Diagnostic>;
+    }
+    function getBuilderCreationParameters(newProgramOrRootNames: Program | ReadonlyArray<string> | undefined, hostOrOptions: BuilderProgramHost | CompilerOptions | undefined, oldProgramOrHost?: BuilderProgram | CompilerHost, configFileParsingDiagnosticsOrOldProgram?: ReadonlyArray<Diagnostic> | BuilderProgram, configFileParsingDiagnostics?: ReadonlyArray<Diagnostic>): BuilderCreationParameters;
+    function createBuilderProgram(kind: BuilderProgramKind.SemanticDiagnosticsBuilderProgram, builderCreationParameters: BuilderCreationParameters): SemanticDiagnosticsBuilderProgram;
+    function createBuilderProgram(kind: BuilderProgramKind.EmitAndSemanticDiagnosticsBuilderProgram, builderCreationParameters: BuilderCreationParameters): EmitAndSemanticDiagnosticsBuilderProgram;
+}
 declare namespace ts {
     type AffectedFileResult<T> = {
         result: T;
@@ -4102,6 +9027,7 @@ declare namespace ts {
      * Builder to manage the program state changes
      */
     interface BuilderProgram {
+        getState(): BuilderProgramState;
         /**
          * Returns current program
          */
@@ -4203,6 +9129,99 @@ declare namespace ts {
     function createAbstractBuilder(newProgram: Program, host: BuilderProgramHost, oldProgram?: BuilderProgram, configFileParsingDiagnostics?: ReadonlyArray<Diagnostic>): BuilderProgram;
     function createAbstractBuilder(rootNames: ReadonlyArray<string> | undefined, options: CompilerOptions | undefined, host?: CompilerHost, oldProgram?: BuilderProgram, configFileParsingDiagnostics?: ReadonlyArray<Diagnostic>): BuilderProgram;
 }
+declare namespace ts {
+    /** This is the cache of module/typedirectives resolution that can be retained across program */
+    interface ResolutionCache {
+        startRecordingFilesWithChangedResolutions(): void;
+        finishRecordingFilesWithChangedResolutions(): Path[] | undefined;
+        resolveModuleNames(moduleNames: string[], containingFile: string, reusedNames: string[] | undefined): ResolvedModuleFull[];
+        getResolvedModuleWithFailedLookupLocationsFromCache(moduleName: string, containingFile: string): CachedResolvedModuleWithFailedLookupLocations | undefined;
+        resolveTypeReferenceDirectives(typeDirectiveNames: string[], containingFile: string): ResolvedTypeReferenceDirective[];
+        invalidateResolutionOfFile(filePath: Path): void;
+        removeResolutionsOfFile(filePath: Path): void;
+        setFilesWithInvalidatedNonRelativeUnresolvedImports(filesWithUnresolvedImports: Map<ReadonlyArray<string>>): void;
+        createHasInvalidatedResolution(forceAllFilesAsInvalidated?: boolean): HasInvalidatedResolution;
+        startCachingPerDirectoryResolution(): void;
+        finishCachingPerDirectoryResolution(): void;
+        updateTypeRootsWatch(): void;
+        closeTypeRootsWatch(): void;
+        clear(): void;
+    }
+    interface ResolutionWithFailedLookupLocations {
+        readonly failedLookupLocations: ReadonlyArray<string>;
+        isInvalidated?: boolean;
+        refCount?: number;
+    }
+    interface CachedResolvedModuleWithFailedLookupLocations extends ResolvedModuleWithFailedLookupLocations, ResolutionWithFailedLookupLocations {
+    }
+    interface ResolutionCacheHost extends ModuleResolutionHost {
+        toPath(fileName: string): Path;
+        getCanonicalFileName: GetCanonicalFileName;
+        getCompilationSettings(): CompilerOptions;
+        watchDirectoryOfFailedLookupLocation(directory: string, cb: DirectoryWatcherCallback, flags: WatchDirectoryFlags): FileWatcher;
+        onInvalidatedResolution(): void;
+        watchTypeRootsDirectory(directory: string, cb: DirectoryWatcherCallback, flags: WatchDirectoryFlags): FileWatcher;
+        onChangedAutomaticTypeDirectiveNames(): void;
+        getCachedDirectoryStructureHost(): CachedDirectoryStructureHost | undefined;
+        projectName?: string;
+        getGlobalCache?(): string | undefined;
+        writeLog(s: string): void;
+        maxNumberOfFilesToIterateForInvalidation?: number;
+        getCurrentProgram(): Program;
+    }
+    const maxNumberOfFilesToIterateForInvalidation = 256;
+    function createResolutionCache(resolutionHost: ResolutionCacheHost, rootDirForResolution: string | undefined, logChangesWhenResolvingModule: boolean): ResolutionCache;
+}
+declare namespace ts.moduleSpecifiers {
+    interface ModuleSpecifierPreferences {
+        importModuleSpecifierPreference?: "relative" | "non-relative";
+    }
+    function getModuleSpecifier(compilerOptions: CompilerOptions, fromSourceFile: SourceFile, fromSourceFileName: string, toFileName: string, host: ModuleSpecifierResolutionHost, preferences?: ModuleSpecifierPreferences): string;
+    function getModuleSpecifiers(moduleSymbol: Symbol, program: Program, importingSourceFile: SourceFile, host: ModuleSpecifierResolutionHost, preferences: ModuleSpecifierPreferences): ReadonlyArray<ReadonlyArray<string>>;
+}
+declare namespace ts {
+    /**
+     * Create a function that reports error by writing to the system and handles the formating of the diagnostic
+     */
+    function createDiagnosticReporter(system: System, pretty?: boolean): DiagnosticReporter;
+    /** @internal */
+    const nonClearingMessageCodes: number[];
+    /** @internal */
+    const screenStartingMessageCodes: number[];
+    /**
+     * Create a function that reports watch status by writing to the system and handles the formating of the diagnostic
+     */
+    function createWatchStatusReporter(system: System, pretty?: boolean): WatchStatusReporter;
+    /** Parses config file using System interface */
+    function parseConfigFileWithSystem(configFileName: string, optionsToExtend: CompilerOptions, system: System, reportDiagnostic: DiagnosticReporter): ParsedCommandLine | undefined;
+    /**
+     * Program structure needed to emit the files and report diagnostics
+     */
+    interface ProgramToEmitFilesAndReportErrors {
+        getCurrentDirectory(): string;
+        getCompilerOptions(): CompilerOptions;
+        getSourceFiles(): ReadonlyArray<SourceFile>;
+        getSyntacticDiagnostics(): ReadonlyArray<Diagnostic>;
+        getOptionsDiagnostics(): ReadonlyArray<Diagnostic>;
+        getGlobalDiagnostics(): ReadonlyArray<Diagnostic>;
+        getSemanticDiagnostics(): ReadonlyArray<Diagnostic>;
+        getConfigFileParsingDiagnostics(): ReadonlyArray<Diagnostic>;
+        emit(): EmitResult;
+    }
+    type ReportEmitErrorSummary = (errorCount: number) => void;
+    /**
+     * Helper that emit files, report diagnostics and lists emitted and/or source files depending on compiler options
+     */
+    function emitFilesAndReportErrors(program: ProgramToEmitFilesAndReportErrors, reportDiagnostic: DiagnosticReporter, writeFileName?: (s: string) => void, reportSummary?: ReportEmitErrorSummary): ExitStatus;
+    /**
+     * Creates the watch compiler host from system for config file in watch mode
+     */
+    function createWatchCompilerHostOfConfigFile<T extends BuilderProgram = EmitAndSemanticDiagnosticsBuilderProgram>(configFileName: string, optionsToExtend: CompilerOptions | undefined, system: System, createProgram?: CreateProgram<T>, reportDiagnostic?: DiagnosticReporter, reportWatchStatus?: WatchStatusReporter): WatchCompilerHostOfConfigFile<T>;
+    /**
+     * Creates the watch compiler host from system for compiling root files and options in watch mode
+     */
+    function createWatchCompilerHostOfFilesAndCompilerOptions<T extends BuilderProgram = EmitAndSemanticDiagnosticsBuilderProgram>(rootFiles: string[], options: CompilerOptions, system: System, createProgram?: CreateProgram<T>, reportDiagnostic?: DiagnosticReporter, reportWatchStatus?: WatchStatusReporter): WatchCompilerHostOfFilesAndCompilerOptions<T>;
+}
 declare namespace ts {
     type WatchStatusReporter = (diagnostic: Diagnostic, newLine: string, options: CompilerOptions) => void;
     /** Create the program with rootNames and options, if they are undefined, oldProgram and new configFile diagnostics create new program */
@@ -4216,6 +9235,7 @@ declare namespace ts {
         afterProgramCreate?(program: T): void;
         /** If provided, called with Diagnostic message that informs about change in watch status */
         onWatchStatusChange?(diagnostic: Diagnostic, newLine: string, options: CompilerOptions): void;
+        maxNumberOfFilesToIterateForInvalidation?: number;
         useCaseSensitiveFileNames(): boolean;
         getNewLine(): string;
         getCurrentDirectory(): string;
@@ -4257,6 +9277,12 @@ declare namespace ts {
         /** If provided, will be used to reset existing delayed compilation */
         clearTimeout?(timeoutId: any): void;
     }
+    /** Internal interface used to wire emit through same host */
+    interface WatchCompilerHost<T extends BuilderProgram> {
+        createDirectory?(path: string): void;
+        writeFile?(path: string, data: string, writeByteOrderMark?: boolean): void;
+        onCachedDirectoryStructureHostCreate?(host: CachedDirectoryStructureHost): void;
+    }
     /**
      * Host to create watch with root files and options
      */
@@ -4280,9 +9306,18 @@ declare namespace ts {
          */
         readDirectory(path: string, extensions?: ReadonlyArray<string>, exclude?: ReadonlyArray<string>, include?: ReadonlyArray<string>, depth?: number): string[];
     }
+    /**
+     * Host to create watch with config file that is already parsed (from tsc)
+     */
+    interface WatchCompilerHostOfConfigFile<T extends BuilderProgram> extends WatchCompilerHost<T> {
+        optionsToExtend?: CompilerOptions;
+        configFileParsingResult?: ParsedCommandLine;
+    }
     interface Watch<T> {
         /** Synchronize with host and get updated program */
         getProgram(): T;
+        /** Gets the existing program without synchronizing with changes on host */
+        getCurrentProgram(): T;
     }
     /**
      * Creates the watch what generates program using the config file
@@ -4311,85 +9346,371 @@ declare namespace ts {
     function createWatchProgram<T extends BuilderProgram>(host: WatchCompilerHostOfConfigFile<T>): WatchOfConfigFile<T>;
 }
 declare namespace ts {
-    function parseCommandLine(commandLine: ReadonlyArray<string>, readFile?: (path: string) => string | undefined): ParsedCommandLine;
-    type DiagnosticReporter = (diagnostic: Diagnostic) => void;
     /**
-     * Reports config file diagnostics
+     * Branded string for keeping track of when we've turned an ambiguous path
+     * specified like "./blah" to an absolute path to an actual
+     * tsconfig file, e.g. "/root/blah/tsconfig.json"
      */
-    interface ConfigFileDiagnosticsReporter {
+    type ResolvedConfigFileName = string & {
+        _isResolvedConfigFileName: never;
+    };
+    interface BuildHost {
+        verbose(diag: DiagnosticMessage, ...args: string[]): void;
+        error(diag: DiagnosticMessage, ...args: string[]): void;
+        errorDiagnostic(diag: Diagnostic): void;
+        message(diag: DiagnosticMessage, ...args: string[]): void;
+    }
+    /**
+     * A BuildContext tracks what's going on during the course of a build.
+     *
+     * Callers may invoke any number of build requests within the same context;
+     * until the context is reset, each project will only be built at most once.
+     *
+     * Example: In a standard setup where project B depends on project A, and both are out of date,
+     * a failed build of A will result in A remaining out of date. When we try to build
+     * B, we should immediately bail instead of recomputing A's up-to-date status again.
+     *
+     * This also matters for performing fast (i.e. fake) downstream builds of projects
+     * when their upstream .d.ts files haven't changed content (but have newer timestamps)
+     */
+    interface BuildContext {
+        options: BuildOptions;
         /**
-         * Reports unrecoverable error when parsing config file
+         * Map from output file name to its pre-build timestamp
          */
-        onUnRecoverableConfigFileDiagnostic: DiagnosticReporter;
+        unchangedOutputs: FileMap<Date>;
+        /**
+         * Map from config file name to up-to-date status
+         */
+        projectStatus: FileMap<UpToDateStatus>;
+        invalidatedProjects: FileMap<true>;
+        queuedProjects: FileMap<true>;
+        missingRoots: Map<true>;
     }
-    /**
-     * Interface extending ParseConfigHost to support ParseConfigFile that reads config file and reports errors
-     */
-    interface ParseConfigFileHost extends ParseConfigHost, ConfigFileDiagnosticsReporter {
-        getCurrentDirectory(): string;
+    type Mapper = ReturnType<typeof createDependencyMapper>;
+    interface DependencyGraph {
+        buildQueue: ResolvedConfigFileName[];
+        dependencyMap: Mapper;
     }
-    /**
-     * Reads the config file, reports errors if any and exits if the config file cannot be found
-     */
-    function getParsedCommandLineOfConfigFile(configFileName: string, optionsToExtend: CompilerOptions, host: ParseConfigFileHost): ParsedCommandLine | undefined;
-    /**
-     * Read tsconfig.json file
-     * @param fileName The path to the config file
-     */
-    function readConfigFile(fileName: string, readFile: (path: string) => string | undefined): {
-        config?: any;
-        error?: Diagnostic;
+    interface BuildOptions {
+        dry: boolean;
+        force: boolean;
+        verbose: boolean;
+    }
+    enum UpToDateStatusType {
+        Unbuildable = 0,
+        UpToDate = 1,
+        /**
+         * The project appears out of date because its upstream inputs are newer than its outputs,
+         * but all of its outputs are actually newer than the previous identical outputs of its (.d.ts) inputs.
+         * This means we can Pseudo-build (just touch timestamps), as if we had actually built this project.
+         */
+        UpToDateWithUpstreamTypes = 2,
+        OutputMissing = 3,
+        OutOfDateWithSelf = 4,
+        OutOfDateWithUpstream = 5,
+        UpstreamOutOfDate = 6,
+        UpstreamBlocked = 7,
+        /**
+         * Projects with no outputs (i.e. "solution" files)
+         */
+        ContainerOnly = 8
+    }
+    type UpToDateStatus = Status.Unbuildable | Status.UpToDate | Status.OutputMissing | Status.OutOfDateWithSelf | Status.OutOfDateWithUpstream | Status.UpstreamOutOfDate | Status.UpstreamBlocked | Status.ContainerOnly;
+    namespace Status {
+        /**
+         * The project can't be built at all in its current state. For example,
+         * its config file cannot be parsed, or it has a syntax error or missing file
+         */
+        interface Unbuildable {
+            type: UpToDateStatusType.Unbuildable;
+            reason: string;
+        }
+        /**
+         * This project doesn't have any outputs, so "is it up to date" is a meaningless question.
+         */
+        interface ContainerOnly {
+            type: UpToDateStatusType.ContainerOnly;
+        }
+        /**
+         * The project is up to date with respect to its inputs.
+         * We track what the newest input file is.
+         */
+        interface UpToDate {
+            type: UpToDateStatusType.UpToDate | UpToDateStatusType.UpToDateWithUpstreamTypes;
+            newestInputFileTime: Date;
+            newestInputFileName: string;
+            newestDeclarationFileContentChangedTime: Date;
+            newestOutputFileTime: Date;
+            newestOutputFileName: string;
+            oldestOutputFileName: string;
+        }
+        /**
+         * One or more of the outputs of the project does not exist.
+         */
+        interface OutputMissing {
+            type: UpToDateStatusType.OutputMissing;
+            /**
+             * The name of the first output file that didn't exist
+             */
+            missingOutputFileName: string;
+        }
+        /**
+         * One or more of the project's outputs is older than its newest input.
+         */
+        interface OutOfDateWithSelf {
+            type: UpToDateStatusType.OutOfDateWithSelf;
+            outOfDateOutputFileName: string;
+            newerInputFileName: string;
+        }
+        /**
+         * This project depends on an out-of-date project, so shouldn't be built yet
+         */
+        interface UpstreamOutOfDate {
+            type: UpToDateStatusType.UpstreamOutOfDate;
+            upstreamProjectName: string;
+        }
+        /**
+         * This project depends an upstream project with build errors
+         */
+        interface UpstreamBlocked {
+            type: UpToDateStatusType.UpstreamBlocked;
+            upstreamProjectName: string;
+        }
+        /**
+         * One or more of the project's outputs is older than the newest output of
+         * an upstream project.
+         */
+        interface OutOfDateWithUpstream {
+            type: UpToDateStatusType.OutOfDateWithUpstream;
+            outOfDateOutputFileName: string;
+            newerProjectName: string;
+        }
+    }
+    interface FileMap<T> {
+        setValue(fileName: string, value: T): void;
+        getValue(fileName: string): T | never;
+        getValueOrUndefined(fileName: string): T | undefined;
+        hasKey(fileName: string): boolean;
+        removeKey(fileName: string): void;
+        getKeys(): string[];
+    }
+    function createDependencyMapper(): {
+        addReference: (childConfigFileName: ResolvedConfigFileName, parentConfigFileName: ResolvedConfigFileName) => void;
+        getReferencesTo: (parentConfigFileName: ResolvedConfigFileName) => ResolvedConfigFileName[];
+        getReferencesOf: (childConfigFileName: ResolvedConfigFileName) => ResolvedConfigFileName[];
+        getKeys: () => ReadonlyArray<ResolvedConfigFileName>;
     };
+    function createBuildContext(options: BuildOptions): BuildContext;
+    function performBuild(args: string[], compilerHost: CompilerHost, buildHost: BuildHost, system?: System): number | undefined;
     /**
-     * Parse the text of the tsconfig.json file
-     * @param fileName The path to the config file
-     * @param jsonText The text of the config file
+     * A SolutionBuilder has an immutable set of rootNames that are the "entry point" projects, but
+     * can dynamically add/remove other projects based on changes on the rootNames' references
      */
-    function parseConfigFileTextToJson(fileName: string, jsonText: string): {
-        config?: any;
-        error?: Diagnostic;
-    };
-    /**
-     * Read tsconfig.json file
-     * @param fileName The path to the config file
-     */
-    function readJsonConfigFile(fileName: string, readFile: (path: string) => string | undefined): TsConfigSourceFile;
-    /**
-     * Convert the json syntax tree into the json value
-     */
-    function convertToObject(sourceFile: JsonSourceFile, errors: Push<Diagnostic>): any;
-    /**
-     * Parse the contents of a config file (tsconfig.json).
-     * @param json The contents of the config file to parse
-     * @param host Instance of ParseConfigHost used to enumerate files in folder.
-     * @param basePath A root directory to resolve relative path entries in the config
-     *    file to. e.g. outDir
-     */
-    function parseJsonConfigFileContent(json: any, host: ParseConfigHost, basePath: string, existingOptions?: CompilerOptions, configFileName?: string, resolutionStack?: Path[], extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): ParsedCommandLine;
-    /**
-     * Parse the contents of a config file (tsconfig.json).
-     * @param jsonNode The contents of the config file to parse
-     * @param host Instance of ParseConfigHost used to enumerate files in folder.
-     * @param basePath A root directory to resolve relative path entries in the config
-     *    file to. e.g. outDir
-     */
-    function parseJsonSourceFileConfigFileContent(sourceFile: TsConfigSourceFile, host: ParseConfigHost, basePath: string, existingOptions?: CompilerOptions, configFileName?: string, resolutionStack?: Path[], extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): ParsedCommandLine;
-    function convertCompilerOptionsFromJson(jsonOptions: any, basePath: string, configFileName?: string): {
-        options: CompilerOptions;
-        errors: Diagnostic[];
-    };
-    function convertTypeAcquisitionFromJson(jsonOptions: any, basePath: string, configFileName?: string): {
-        options: TypeAcquisition;
-        errors: Diagnostic[];
+    function createSolutionBuilder(compilerHost: CompilerHost, buildHost: BuildHost, rootNames: ReadonlyArray<string>, defaultOptions: BuildOptions, system?: System): {
+        buildAllProjects: () => number;
+        getUpToDateStatus: (project: ParsedCommandLine | undefined) => UpToDateStatus;
+        getUpToDateStatusOfFile: (configFileName: ResolvedConfigFileName) => UpToDateStatus;
+        cleanAllProjects: () => ExitStatus.Success | ExitStatus.DiagnosticsPresent_OutputsSkipped;
+        resetBuildContext: (opts?: BuildOptions) => void;
+        getBuildGraph: (configFileNames: ReadonlyArray<string>) => DependencyGraph | undefined;
+        invalidateProject: (configFileName: string) => void;
+        buildInvalidatedProjects: () => void;
+        buildDependentInvalidatedProjects: () => void;
+        resolveProjectName: (name: string) => ResolvedConfigFileName | undefined;
+        startWatching: () => void;
     };
 }
+//# sourceMappingURL=compiler.d.ts.map
+declare namespace ts.server {
+    const ActionSet: ActionSet;
+    const ActionInvalidate: ActionInvalidate;
+    const ActionPackageInstalled: ActionPackageInstalled;
+    const EventTypesRegistry: EventTypesRegistry;
+    const EventBeginInstallTypes: EventBeginInstallTypes;
+    const EventEndInstallTypes: EventEndInstallTypes;
+    const EventInitializationFailed: EventInitializationFailed;
+    namespace Arguments {
+        const GlobalCacheLocation = "--globalTypingsCacheLocation";
+        const LogFile = "--logFile";
+        const EnableTelemetry = "--enableTelemetry";
+        const TypingSafeListLocation = "--typingSafeListLocation";
+        const TypesMapLocation = "--typesMapLocation";
+        /**
+         * This argument specifies the location of the NPM executable.
+         * typingsInstaller will run the command with `${npmLocation} install ...`.
+         */
+        const NpmLocation = "--npmLocation";
+    }
+    function hasArgument(argumentName: string): boolean;
+    function findArgument(argumentName: string): string | undefined;
+    function nowString(): string;
+}
+declare namespace ts.server {
+    type ActionSet = "action::set";
+    type ActionInvalidate = "action::invalidate";
+    type ActionPackageInstalled = "action::packageInstalled";
+    type EventTypesRegistry = "event::typesRegistry";
+    type EventBeginInstallTypes = "event::beginInstallTypes";
+    type EventEndInstallTypes = "event::endInstallTypes";
+    type EventInitializationFailed = "event::initializationFailed";
+    interface SortedReadonlyArray<T> extends ReadonlyArray<T> {
+        " __sortedArrayBrand": any;
+    }
+    interface TypingInstallerResponse {
+        readonly kind: ActionSet | ActionInvalidate | EventTypesRegistry | ActionPackageInstalled | EventBeginInstallTypes | EventEndInstallTypes | EventInitializationFailed;
+    }
+    interface TypingInstallerRequestWithProjectName {
+        readonly projectName: string;
+    }
+    type TypingInstallerRequestUnion = DiscoverTypings | CloseProject | TypesRegistryRequest | InstallPackageRequest;
+    interface DiscoverTypings extends TypingInstallerRequestWithProjectName {
+        readonly fileNames: string[];
+        readonly projectRootPath: Path;
+        readonly compilerOptions: CompilerOptions;
+        readonly typeAcquisition: TypeAcquisition;
+        readonly unresolvedImports: SortedReadonlyArray<string>;
+        readonly cachePath?: string;
+        readonly kind: "discover";
+    }
+    interface CloseProject extends TypingInstallerRequestWithProjectName {
+        readonly kind: "closeProject";
+    }
+    interface TypesRegistryRequest {
+        readonly kind: "typesRegistry";
+    }
+    interface InstallPackageRequest extends TypingInstallerRequestWithProjectName {
+        readonly kind: "installPackage";
+        readonly fileName: Path;
+        readonly packageName: string;
+        readonly projectRootPath: Path;
+    }
+    interface TypesRegistryResponse extends TypingInstallerResponse {
+        readonly kind: EventTypesRegistry;
+        readonly typesRegistry: MapLike<MapLike<string>>;
+    }
+    interface PackageInstalledResponse extends ProjectResponse {
+        readonly kind: ActionPackageInstalled;
+        readonly success: boolean;
+        readonly message: string;
+    }
+    interface InitializationFailedResponse extends TypingInstallerResponse {
+        readonly kind: EventInitializationFailed;
+        readonly message: string;
+    }
+    interface ProjectResponse extends TypingInstallerResponse {
+        readonly projectName: string;
+    }
+    interface InvalidateCachedTypings extends ProjectResponse {
+        readonly kind: ActionInvalidate;
+    }
+    interface InstallTypes extends ProjectResponse {
+        readonly kind: EventBeginInstallTypes | EventEndInstallTypes;
+        readonly eventId: number;
+        readonly typingsInstallerVersion: string;
+        readonly packagesToInstall: ReadonlyArray<string>;
+    }
+    interface BeginInstallTypes extends InstallTypes {
+        readonly kind: EventBeginInstallTypes;
+    }
+    interface EndInstallTypes extends InstallTypes {
+        readonly kind: EventEndInstallTypes;
+        readonly installSuccess: boolean;
+    }
+    interface InstallTypingHost extends JsTyping.TypingResolutionHost {
+        useCaseSensitiveFileNames: boolean;
+        writeFile(path: string, content: string): void;
+        createDirectory(path: string): void;
+        watchFile?(path: string, callback: FileWatcherCallback, pollingInterval?: number): FileWatcher;
+        watchDirectory?(path: string, callback: DirectoryWatcherCallback, recursive?: boolean): FileWatcher;
+    }
+    interface SetTypings extends ProjectResponse {
+        readonly typeAcquisition: TypeAcquisition;
+        readonly compilerOptions: CompilerOptions;
+        readonly typings: string[];
+        readonly unresolvedImports: SortedReadonlyArray<string>;
+        readonly kind: ActionSet;
+    }
+    type TypingInstallerResponseUnion = SetTypings | InvalidateCachedTypings | TypesRegistryResponse | PackageInstalledResponse | InstallTypes | InitializationFailedResponse;
+}
+declare namespace ts.JsTyping {
+    interface TypingResolutionHost {
+        directoryExists(path: string): boolean;
+        fileExists(fileName: string): boolean;
+        readFile(path: string, encoding?: string): string | undefined;
+        readDirectory(rootDir: string, extensions: ReadonlyArray<string>, excludes: ReadonlyArray<string> | undefined, includes: ReadonlyArray<string> | undefined, depth?: number): string[];
+    }
+    interface CachedTyping {
+        typingLocation: string;
+        version: Semver;
+    }
+    function isTypingUpToDate(cachedTyping: CachedTyping, availableTypingVersions: MapLike<string>): boolean;
+    const nodeCoreModuleList: ReadonlyArray<string>;
+    const nodeCoreModules: Map<true>;
+    /**
+     * A map of loose file names to library names that we are confident require typings
+     */
+    type SafeList = ReadonlyMap<string>;
+    function loadSafeList(host: TypingResolutionHost, safeListPath: Path): SafeList;
+    function loadTypesMap(host: TypingResolutionHost, typesMapPath: Path): SafeList | undefined;
+    /**
+     * @param host is the object providing I/O related operations.
+     * @param fileNames are the file names that belong to the same project
+     * @param projectRootPath is the path to the project root directory
+     * @param safeListPath is the path used to retrieve the safe list
+     * @param packageNameToTypingLocation is the map of package names to their cached typing locations and installed versions
+     * @param typeAcquisition is used to customize the typing acquisition process
+     * @param compilerOptions are used as a source for typing inference
+     */
+    function discoverTypings(host: TypingResolutionHost, log: ((message: string) => void) | undefined, fileNames: string[], projectRootPath: Path, safeList: SafeList, packageNameToTypingLocation: ReadonlyMap<CachedTyping>, typeAcquisition: TypeAcquisition, unresolvedImports: ReadonlyArray<string>, typesRegistry: ReadonlyMap<MapLike<string>>): {
+        cachedTypingPaths: string[];
+        newTypingNames: string[];
+        filesToWatch: string[];
+    };
+    enum PackageNameValidationResult {
+        Ok = 0,
+        ScopedPackagesNotSupported = 1,
+        EmptyName = 2,
+        NameTooLong = 3,
+        NameStartsWithDot = 4,
+        NameStartsWithUnderscore = 5,
+        NameContainsNonURISafeCharacters = 6
+    }
+    /**
+     * Validates package name using rules defined at https://docs.npmjs.com/files/package.json
+     */
+    function validatePackageName(packageName: string): PackageNameValidationResult;
+    function renderPackageNameValidationFailure(result: PackageNameValidationResult, typing: string): string;
+}
+declare namespace ts {
+    class Semver {
+        readonly major: number;
+        readonly minor: number;
+        readonly patch: number;
+        /**
+         * If true, this is `major.minor.0-next.patch`.
+         * If false, this is `major.minor.patch`.
+         */
+        readonly isPrerelease: boolean;
+        static parse(semver: string): Semver;
+        static fromRaw({ major, minor, patch, isPrerelease }: Semver): Semver;
+        private static tryParse;
+        private constructor();
+        readonly versionString: string;
+        equals(sem: Semver): boolean;
+        greaterThan(sem: Semver): boolean;
+    }
+}
+//# sourceMappingURL=jsTyping.d.ts.map
 declare namespace ts {
     interface Node {
         getSourceFile(): SourceFile;
         getChildCount(sourceFile?: SourceFile): number;
         getChildAt(index: number, sourceFile?: SourceFile): Node;
         getChildren(sourceFile?: SourceFile): Node[];
+        getChildren(sourceFile?: SourceFileLike): Node[];
         getStart(sourceFile?: SourceFile, includeJsDocComment?: boolean): number;
+        getStart(sourceFile?: SourceFileLike, includeJsDocComment?: boolean): number;
         getFullStart(): number;
         getEnd(): number;
         getWidth(sourceFile?: SourceFileLike): number;
@@ -4446,14 +9767,20 @@ declare namespace ts {
         getJsDocTags(): JSDocTagInfo[];
     }
     interface SourceFile {
+        version: string;
+        scriptSnapshot: IScriptSnapshot | undefined;
+        nameTable: UnderscoreEscapedMap<number> | undefined;
+        getNamedDeclarations(): Map<Declaration[]>;
         getLineAndCharacterOfPosition(pos: number): LineAndCharacter;
         getLineEndOfPosition(pos: number): number;
         getLineStarts(): ReadonlyArray<number>;
         getPositionOfLineAndCharacter(line: number, character: number): number;
         update(newText: string, textChangeRange: TextChangeRange): SourceFile;
+        sourceMapper?: sourcemaps.SourceMapper;
     }
     interface SourceFileLike {
         getLineAndCharacterOfPosition(pos: number): LineAndCharacter;
+        sourceMapper?: sourcemaps.SourceMapper;
     }
     interface SourceMapSource {
         getLineAndCharacterOfPosition(pos: number): LineAndCharacter;
@@ -4522,6 +9849,8 @@ declare namespace ts {
         resolveModuleNames?(moduleNames: string[], containingFile: string, reusedNames?: string[]): ResolvedModule[];
         getResolvedModuleWithFailedLookupLocationsFromCache?(modulename: string, containingFile: string): ResolvedModuleWithFailedLookupLocations | undefined;
         resolveTypeReferenceDirectives?(typeDirectiveNames: string[], containingFile: string): ResolvedTypeReferenceDirective[];
+        hasInvalidatedResolution?: HasInvalidatedResolution;
+        hasChangedAutomaticTypeDirectiveNames?: boolean;
         getDirectories?(directoryName: string): string[];
         /**
          * Gets a set of custom transformers to use during emit.
@@ -4538,6 +9867,7 @@ declare namespace ts {
         readonly importModuleSpecifierPreference?: "relative" | "non-relative";
         readonly allowTextChangesInNewFiles?: boolean;
     }
+    const defaultPreferences: UserPreferences;
     interface LanguageService {
         cleanupSemanticCache(): void;
         getSyntacticDiagnostics(fileName: string): DiagnosticWithLocation[];
@@ -4609,6 +9939,7 @@ declare namespace ts {
         getEditsForFileRename(oldFilePath: string, newFilePath: string, formatOptions: FormatCodeSettings, preferences: UserPreferences | undefined): ReadonlyArray<FileTextChanges>;
         getEmitOutput(fileName: string, emitOnlyDtsFiles?: boolean): EmitOutput;
         getProgram(): Program | undefined;
+        getNonBoundSourceFile(fileName: string): SourceFile;
         dispose(): void;
     }
     interface JsxClosingTagInfo {
@@ -4719,6 +10050,9 @@ declare namespace ts {
     }
     type CodeActionCommand = InstallPackageAction;
     interface InstallPackageAction {
+        file: string;
+        type: "install package";
+        packageName: string;
     }
     /**
      * A set of one or more available refactoring actions, grouped under a parent refactoring.
@@ -5230,8 +10564,263 @@ declare namespace ts {
         jsxAttributeStringLiteralValue = 24
     }
 }
+interface PromiseConstructor {
+    new <T>(executor: (resolve: (value?: T | PromiseLike<T>) => void, reject: (reason?: any) => void) => void): Promise<T>;
+    reject(reason: any): Promise<never>;
+    all<T>(values: (T | PromiseLike<T>)[]): Promise<T[]>;
+}
+declare var Promise: PromiseConstructor;
+declare namespace ts {
+    const scanner: Scanner;
+    enum SemanticMeaning {
+        None = 0,
+        Value = 1,
+        Type = 2,
+        Namespace = 4,
+        All = 7
+    }
+    function getMeaningFromDeclaration(node: Node): SemanticMeaning;
+    function getMeaningFromLocation(node: Node): SemanticMeaning;
+    function isInRightSideOfInternalImportEqualsDeclaration(node: Node): boolean;
+    function isCallExpressionTarget(node: Node): boolean;
+    function isNewExpressionTarget(node: Node): boolean;
+    function climbPastPropertyAccess(node: Node): Node;
+    function getTargetLabel(referenceNode: Node, labelName: string): Identifier | undefined;
+    function isJumpStatementTarget(node: Node): node is Identifier & {
+        parent: BreakOrContinueStatement;
+    };
+    function isLabelOfLabeledStatement(node: Node): node is Identifier;
+    function isLabelName(node: Node): boolean;
+    function isRightSideOfQualifiedName(node: Node): boolean;
+    function isRightSideOfPropertyAccess(node: Node): boolean;
+    function isNameOfModuleDeclaration(node: Node): boolean;
+    function isNameOfFunctionDeclaration(node: Node): boolean;
+    function isLiteralNameOfPropertyDeclarationOrIndexAccess(node: StringLiteral | NumericLiteral): boolean;
+    function isExpressionOfExternalModuleImportEqualsDeclaration(node: Node): boolean;
+    function getContainerNode(node: Node): Declaration | undefined;
+    function getNodeKind(node: Node): ScriptElementKind;
+    function isThis(node: Node): boolean;
+    interface ListItemInfo {
+        listItemIndex: number;
+        list: Node;
+    }
+    function getLineStartPositionForPosition(position: number, sourceFile: SourceFileLike): number;
+    function rangeContainsRange(r1: TextRange, r2: TextRange): boolean;
+    function rangeContainsPosition(r: TextRange, pos: number): boolean;
+    function rangeContainsPositionExclusive(r: TextRange, pos: number): boolean;
+    function startEndContainsRange(start: number, end: number, range: TextRange): boolean;
+    function rangeContainsStartEnd(range: TextRange, start: number, end: number): boolean;
+    function rangeOverlapsWithStartEnd(r1: TextRange, start: number, end: number): boolean;
+    function startEndOverlapsWithStartEnd(start1: number, end1: number, start2: number, end2: number): boolean;
+    /**
+     * Assumes `candidate.start <= position` holds.
+     */
+    function positionBelongsToNode(candidate: Node, position: number, sourceFile: SourceFile): boolean;
+    function findListItemInfo(node: Node): ListItemInfo | undefined;
+    function hasChildOfKind(n: Node, kind: SyntaxKind, sourceFile: SourceFile): boolean;
+    function findChildOfKind<T extends Node>(n: Node, kind: T["kind"], sourceFile: SourceFileLike): T | undefined;
+    function findContainingList(node: Node): SyntaxList | undefined;
+    /**
+     * Gets the token whose text has range [start, end) and
+     * position >= start and (position < end or (position === end && token is literal or keyword or identifier))
+     */
+    function getTouchingPropertyName(sourceFile: SourceFile, position: number): Node;
+    /**
+     * Returns the token if position is in [start, end).
+     * If position === end, returns the preceding token if includeItemAtEndPosition(previousToken) === true
+     */
+    function getTouchingToken(sourceFile: SourceFile, position: number, includeJsDocComment: boolean, includePrecedingTokenAtEndPosition?: (n: Node) => boolean): Node;
+    /** Returns a token if position is in [start-of-leading-trivia, end) */
+    function getTokenAtPosition(sourceFile: SourceFile, position: number, includeJsDocComment: boolean, includeEndPosition?: boolean): Node;
+    /**
+     * The token on the left of the position is the token that strictly includes the position
+     * or sits to the left of the cursor if it is on a boundary. For example
+     *
+     *   fo|o               -> will return foo
+     *   foo <comment> |bar -> will return foo
+     *
+     */
+    function findTokenOnLeftOfPosition(file: SourceFile, position: number): Node | undefined;
+    function findNextToken(previousToken: Node, parent: Node, sourceFile: SourceFile): Node | undefined;
+    /**
+     * Finds the rightmost token satisfying `token.end <= position`,
+     * excluding `JsxText` tokens containing only whitespace.
+     */
+    function findPrecedingToken(position: number, sourceFile: SourceFile, startNode?: Node, includeJsDoc?: boolean): Node | undefined;
+    function isInString(sourceFile: SourceFile, position: number, previousToken?: Node | undefined): boolean;
+    /**
+     * returns true if the position is in between the open and close elements of an JSX expression.
+     */
+    function isInsideJsxElementOrAttribute(sourceFile: SourceFile, position: number): boolean;
+    function isInTemplateString(sourceFile: SourceFile, position: number): boolean;
+    function findPrecedingMatchingToken(token: Node, matchingTokenKind: SyntaxKind, sourceFile: SourceFile): Node | undefined;
+    interface PossibleTypeArgumentInfo {
+        readonly called: Identifier;
+        readonly nTypeArguments: number;
+    }
+    function isPossiblyTypeArgumentPosition(tokenIn: Node, sourceFile: SourceFile): PossibleTypeArgumentInfo | undefined;
+    /**
+     * Returns true if the cursor at position in sourceFile is within a comment.
+     *
+     * @param tokenAtPosition Must equal `getTokenAtPosition(sourceFile, position)
+     * @param predicate Additional predicate to test on the comment range.
+     */
+    function isInComment(sourceFile: SourceFile, position: number, tokenAtPosition?: Node, predicate?: (c: CommentRange) => boolean): boolean;
+    function hasDocComment(sourceFile: SourceFile, position: number): boolean | undefined;
+    function getNodeModifiers(node: Node): string;
+    function getTypeArgumentOrTypeParameterList(node: Node): NodeArray<Node> | undefined;
+    function isComment(kind: SyntaxKind): boolean;
+    function isStringOrRegularExpressionOrTemplateLiteral(kind: SyntaxKind): boolean;
+    function isPunctuation(kind: SyntaxKind): boolean;
+    function isInsideTemplateLiteral(node: TemplateLiteralToken, position: number, sourceFile: SourceFile): boolean;
+    function isAccessibilityModifier(kind: SyntaxKind): boolean;
+    function cloneCompilerOptions(options: CompilerOptions): CompilerOptions;
+    function isArrayLiteralOrObjectLiteralDestructuringPattern(node: Node): boolean;
+    function isInReferenceComment(sourceFile: SourceFile, position: number): boolean;
+    function isInNonReferenceComment(sourceFile: SourceFile, position: number): boolean;
+    function createTextSpanFromNode(node: Node, sourceFile?: SourceFile): TextSpan;
+    function createTextSpanFromRange(range: TextRange): TextSpan;
+    function createTextRangeFromSpan(span: TextSpan): TextRange;
+    function createTextChangeFromStartLength(start: number, length: number, newText: string): TextChange;
+    function createTextChange(span: TextSpan, newText: string): TextChange;
+    const typeKeywords: ReadonlyArray<SyntaxKind>;
+    function isTypeKeyword(kind: SyntaxKind): boolean;
+    /** True if the symbol is for an external module, as opposed to a namespace. */
+    function isExternalModuleSymbol(moduleSymbol: Symbol): boolean;
+    /** Returns `true` the first time it encounters a node and `false` afterwards. */
+    type NodeSeenTracker<T = Node> = (node: T) => boolean;
+    function nodeSeenTracker<T extends Node>(): NodeSeenTracker<T>;
+    function getSnapshotText(snap: IScriptSnapshot): string;
+    function repeatString(str: string, count: number): string;
+    function skipConstraint(type: Type): Type;
+    function getNameFromPropertyName(name: PropertyName): string | undefined;
+    function programContainsEs6Modules(program: Program): boolean;
+    function compilerOptionsIndicateEs6Modules(compilerOptions: CompilerOptions): boolean;
+    function hostUsesCaseSensitiveFileNames(host: LanguageServiceHost): boolean;
+    function hostGetCanonicalFileName(host: LanguageServiceHost): GetCanonicalFileName;
+    function makeImportIfNecessary(defaultImport: Identifier | undefined, namedImports: ReadonlyArray<ImportSpecifier> | undefined, moduleSpecifier: string, quotePreference: QuotePreference): ImportDeclaration | undefined;
+    function makeImport(defaultImport: Identifier | undefined, namedImports: ReadonlyArray<ImportSpecifier> | undefined, moduleSpecifier: string | Expression, quotePreference: QuotePreference): ImportDeclaration;
+    function makeStringLiteral(text: string, quotePreference: QuotePreference): StringLiteral;
+    enum QuotePreference {
+        Single = 0,
+        Double = 1
+    }
+    function getQuotePreference(sourceFile: SourceFile, preferences: UserPreferences): QuotePreference;
+    function symbolNameNoDefault(symbol: Symbol): string | undefined;
+    function symbolEscapedNameNoDefault(symbol: Symbol): __String | undefined;
+    function getPropertySymbolFromBindingElement(checker: TypeChecker, bindingElement: BindingElement & {
+        name: Identifier;
+    }): Symbol | undefined;
+    /**
+     * Find symbol of the given property-name and add the symbol to the given result array
+     * @param symbol a symbol to start searching for the given propertyName
+     * @param propertyName a name of property to search for
+     * @param result an array of symbol of found property symbols
+     * @param previousIterationSymbolsCache a cache of symbol from previous iterations of calling this function to prevent infinite revisiting of the same symbol.
+     *                                The value of previousIterationSymbol is undefined when the function is first called.
+     */
+    function getPropertySymbolsFromBaseTypes<T>(symbol: Symbol, propertyName: string, checker: TypeChecker, cb: (symbol: Symbol) => T | undefined): T | undefined;
+    function isMemberSymbolInBaseType(memberSymbol: Symbol, checker: TypeChecker): boolean;
+    class NodeSet {
+        private map;
+        add(node: Node): void;
+        has(node: Node): boolean;
+        forEach(cb: (node: Node) => void): void;
+        some(pred: (node: Node) => boolean): boolean;
+    }
+    function getParentNodeInSpan(node: Node | undefined, file: SourceFile, span: TextSpan): Node | undefined;
+}
+declare namespace ts {
+    function isFirstDeclarationOfSymbolParameter(symbol: Symbol): boolean;
+    function symbolPart(text: string, symbol: Symbol): SymbolDisplayPart;
+    function displayPart(text: string, kind: SymbolDisplayPartKind): SymbolDisplayPart;
+    function spacePart(): SymbolDisplayPart;
+    function keywordPart(kind: SyntaxKind): SymbolDisplayPart;
+    function punctuationPart(kind: SyntaxKind): SymbolDisplayPart;
+    function operatorPart(kind: SyntaxKind): SymbolDisplayPart;
+    function textOrKeywordPart(text: string): SymbolDisplayPart;
+    function textPart(text: string): SymbolDisplayPart;
+    /**
+     * The default is CRLF.
+     */
+    function getNewLineOrDefaultFromHost(host: LanguageServiceHost | LanguageServiceShimHost, formatSettings?: FormatCodeSettings): string;
+    function lineBreakPart(): SymbolDisplayPart;
+    function mapToDisplayParts(writeDisplayParts: (writer: DisplayPartsSymbolWriter) => void): SymbolDisplayPart[];
+    function typeToDisplayParts(typechecker: TypeChecker, type: Type, enclosingDeclaration?: Node, flags?: TypeFormatFlags): SymbolDisplayPart[];
+    function symbolToDisplayParts(typeChecker: TypeChecker, symbol: Symbol, enclosingDeclaration?: Node, meaning?: SymbolFlags, flags?: SymbolFormatFlags): SymbolDisplayPart[];
+    function signatureToDisplayParts(typechecker: TypeChecker, signature: Signature, enclosingDeclaration?: Node, flags?: TypeFormatFlags): SymbolDisplayPart[];
+    function isImportOrExportSpecifierName(location: Node): location is Identifier;
+    /**
+     * Strip off existed single quotes or double quotes from a given string
+     *
+     * @return non-quoted string
+     */
+    function stripQuotes(name: string): string;
+    function startsWithQuote(name: string): boolean;
+    function scriptKindIs(fileName: string, host: LanguageServiceHost, ...scriptKinds: ScriptKind[]): boolean;
+    function getScriptKind(fileName: string, host?: LanguageServiceHost): ScriptKind;
+    function getUniqueSymbolId(symbol: Symbol, checker: TypeChecker): number;
+    function getFirstNonSpaceCharacterPosition(text: string, position: number): number;
+    /**
+     * Creates a deep, memberwise clone of a node with no source map location.
+     *
+     * WARNING: This is an expensive operation and is only intended to be used in refactorings
+     * and code fixes (because those are triggered by explicit user actions).
+     */
+    function getSynthesizedDeepClone<T extends Node | undefined>(node: T, includeTrivia?: boolean): T;
+    function getSynthesizedDeepClones<T extends Node>(nodes: NodeArray<T>, includeTrivia?: boolean): NodeArray<T>;
+    function getSynthesizedDeepClones<T extends Node>(nodes: NodeArray<T> | undefined, includeTrivia?: boolean): NodeArray<T> | undefined;
+    /**
+     * Sets EmitFlags to suppress leading and trailing trivia on the node.
+     */
+    function suppressLeadingAndTrailingTrivia(node: Node): void;
+    /**
+     * Sets EmitFlags to suppress leading trivia on the node.
+     */
+    function suppressLeadingTrivia(node: Node): void;
+    /**
+     * Sets EmitFlags to suppress trailing trivia on the node.
+     */
+    function suppressTrailingTrivia(node: Node): void;
+    function getUniqueName(baseName: string, sourceFile: SourceFile): string;
+    /**
+     * @return The index of the (only) reference to the extracted symbol.  We want the cursor
+     * to be on the reference, rather than the declaration, because it's closer to where the
+     * user was before extracting it.
+     */
+    function getRenameLocation(edits: ReadonlyArray<FileTextChanges>, renameFilename: string, name: string, preferLastLocation: boolean): number;
+    function copyComments(sourceNode: Node, targetNode: Node, sourceFile: SourceFile, commentKind?: CommentKind, hasTrailingNewLine?: boolean): void;
+}
 declare namespace ts {
     function createClassifier(): Classifier;
+    function getSemanticClassifications(typeChecker: TypeChecker, cancellationToken: CancellationToken, sourceFile: SourceFile, classifiableNames: UnderscoreEscapedMap<true>, span: TextSpan): ClassifiedSpan[];
+    function getEncodedSemanticClassifications(typeChecker: TypeChecker, cancellationToken: CancellationToken, sourceFile: SourceFile, classifiableNames: UnderscoreEscapedMap<true>, span: TextSpan): Classifications;
+    function getSyntacticClassifications(cancellationToken: CancellationToken, sourceFile: SourceFile, span: TextSpan): ClassifiedSpan[];
+    function getEncodedSyntacticClassifications(cancellationToken: CancellationToken, sourceFile: SourceFile, span: TextSpan): Classifications;
+}
+declare namespace ts.Completions.PathCompletions {
+    interface NameAndKind {
+        readonly name: string;
+        readonly kind: ScriptElementKind.scriptElement | ScriptElementKind.directory | ScriptElementKind.externalModuleName;
+    }
+    interface PathCompletion extends NameAndKind {
+        readonly span: TextSpan | undefined;
+    }
+    function getStringLiteralCompletionsFromModuleNames(sourceFile: SourceFile, node: LiteralExpression, compilerOptions: CompilerOptions, host: LanguageServiceHost, typeChecker: TypeChecker): ReadonlyArray<PathCompletion>;
+    function getTripleSlashReferenceCompletion(sourceFile: SourceFile, position: number, compilerOptions: CompilerOptions, host: LanguageServiceHost): ReadonlyArray<PathCompletion> | undefined;
+}
+declare namespace ts.Completions {
+    type Log = (message: string) => void;
+    function getCompletionsAtPosition(host: LanguageServiceHost, program: Program, log: Log, sourceFile: SourceFile, position: number, preferences: UserPreferences, triggerCharacter: CompletionsTriggerCharacter | undefined): CompletionInfo | undefined;
+    interface CompletionEntryIdentifier {
+        name: string;
+        source?: string;
+    }
+    function getCompletionEntryDetails(program: Program, log: Log, sourceFile: SourceFile, position: number, entryId: CompletionEntryIdentifier, host: LanguageServiceHost, formatContext: formatting.FormatContext, getCanonicalFileName: GetCanonicalFileName, preferences: UserPreferences, cancellationToken: CancellationToken): CompletionEntryDetails | undefined;
+    function getCompletionEntrySymbol(program: Program, log: Log, sourceFile: SourceFile, position: number, entryId: CompletionEntryIdentifier): Symbol | undefined;
+}
+declare namespace ts.DocumentHighlights {
+    function getDocumentHighlights(program: Program, cancellationToken: CancellationToken, sourceFile: SourceFile, position: number, sourceFilesToSearch: ReadonlyArray<SourceFile>): DocumentHighlights[] | undefined;
 }
 declare namespace ts {
     /**
@@ -5292,16 +10881,271 @@ declare namespace ts {
          */
         releaseDocument(fileName: string, compilationSettings: CompilerOptions): void;
         releaseDocumentWithKey(path: Path, key: DocumentRegistryBucketKey): void;
+        getLanguageServiceRefCounts(path: Path): [string, number | undefined][];
         reportStats(): string;
     }
+    interface ExternalDocumentCache {
+        setDocument(key: DocumentRegistryBucketKey, path: Path, sourceFile: SourceFile): void;
+        getDocument(key: DocumentRegistryBucketKey, path: Path): SourceFile | undefined;
+    }
     type DocumentRegistryBucketKey = string & {
         __bucketKey: any;
     };
     function createDocumentRegistry(useCaseSensitiveFileNames?: boolean, currentDirectory?: string): DocumentRegistry;
+    function createDocumentRegistryInternal(useCaseSensitiveFileNames?: boolean, currentDirectory?: string, externalCache?: ExternalDocumentCache): DocumentRegistry;
+}
+declare namespace ts.FindAllReferences {
+    interface ImportsResult {
+        /** For every import of the symbol, the location and local symbol for the import. */
+        importSearches: ReadonlyArray<[Identifier, Symbol]>;
+        /** For rename imports/exports `{ foo as bar }`, `foo` is not a local, so it may be added as a reference immediately without further searching. */
+        singleReferences: ReadonlyArray<Identifier | StringLiteral>;
+        /** List of source files that may (or may not) use the symbol via a namespace. (For UMD modules this is every file.) */
+        indirectUsers: ReadonlyArray<SourceFile>;
+    }
+    type ImportTracker = (exportSymbol: Symbol, exportInfo: ExportInfo, isForRename: boolean) => ImportsResult;
+    /** Creates the imports map and returns an ImportTracker that uses it. Call this lazily to avoid calling `getDirectImportsMap` unnecessarily.  */
+    function createImportTracker(sourceFiles: ReadonlyArray<SourceFile>, sourceFilesSet: ReadonlyMap<true>, checker: TypeChecker, cancellationToken: CancellationToken): ImportTracker;
+    /** Info about an exported symbol to perform recursive search on. */
+    interface ExportInfo {
+        exportingModuleSymbol: Symbol;
+        exportKind: ExportKind;
+    }
+    enum ExportKind {
+        Named = 0,
+        Default = 1,
+        ExportEquals = 2
+    }
+    enum ImportExport {
+        Import = 0,
+        Export = 1
+    }
+    type ModuleReference = {
+        kind: "import";
+        literal: StringLiteralLike;
+    }
+    /** <reference path> or <reference types> */
+     | {
+        kind: "reference";
+        referencingFile: SourceFile;
+        ref: FileReference;
+    };
+    function findModuleReferences(program: Program, sourceFiles: ReadonlyArray<SourceFile>, searchModuleSymbol: Symbol): ModuleReference[];
+    interface ImportedSymbol {
+        kind: ImportExport.Import;
+        symbol: Symbol;
+        isNamedImport: boolean;
+    }
+    interface ExportedSymbol {
+        kind: ImportExport.Export;
+        symbol: Symbol;
+        exportInfo: ExportInfo;
+    }
+    /**
+     * Given a local reference, we might notice that it's an import/export and recursively search for references of that.
+     * If at an import, look locally for the symbol it imports.
+     * If an an export, look for all imports of it.
+     * This doesn't handle export specifiers; that is done in `getReferencesAtExportSpecifier`.
+     * @param comingFromExport If we are doing a search for all exports, don't bother looking backwards for the imported symbol, since that's the reason we're here.
+     */
+    function getImportOrExportSymbol(node: Node, symbol: Symbol, checker: TypeChecker, comingFromExport: boolean): ImportedSymbol | ExportedSymbol | undefined;
+    function getExportInfo(exportSymbol: Symbol, exportKind: ExportKind, checker: TypeChecker): ExportInfo | undefined;
+}
+declare namespace ts.FindAllReferences {
+    interface SymbolAndEntries {
+        definition: Definition | undefined;
+        references: Entry[];
+    }
+    type Definition = {
+        type: "symbol";
+        symbol: Symbol;
+    } | {
+        type: "label";
+        node: Identifier;
+    } | {
+        type: "keyword";
+        node: Node;
+    } | {
+        type: "this";
+        node: Node;
+    } | {
+        type: "string";
+        node: StringLiteral;
+    };
+    type Entry = NodeEntry | SpanEntry;
+    interface NodeEntry {
+        type: "node";
+        node: Node;
+        isInString?: true;
+    }
+    interface SpanEntry {
+        type: "span";
+        fileName: string;
+        textSpan: TextSpan;
+    }
+    function nodeEntry(node: Node, isInString?: true): NodeEntry;
+    interface Options {
+        readonly findInStrings?: boolean;
+        readonly findInComments?: boolean;
+        /**
+         * True if we are renaming the symbol.
+         * If so, we will find fewer references -- if it is referenced by several different names, we sill only find references for the original name.
+         */
+        readonly isForRename?: boolean;
+        /** True if we are searching for implementations. We will have a different method of adding references if so. */
+        readonly implementations?: boolean;
+    }
+    function findReferencedSymbols(program: Program, cancellationToken: CancellationToken, sourceFiles: ReadonlyArray<SourceFile>, sourceFile: SourceFile, position: number): ReferencedSymbol[] | undefined;
+    function getImplementationsAtPosition(program: Program, cancellationToken: CancellationToken, sourceFiles: ReadonlyArray<SourceFile>, sourceFile: SourceFile, position: number): ImplementationLocation[] | undefined;
+    function findReferencedEntries(program: Program, cancellationToken: CancellationToken, sourceFiles: ReadonlyArray<SourceFile>, sourceFile: SourceFile, position: number, options?: Options): ReferenceEntry[] | undefined;
+    function getReferenceEntriesForNode(position: number, node: Node, program: Program, sourceFiles: ReadonlyArray<SourceFile>, cancellationToken: CancellationToken, options?: Options, sourceFilesSet?: ReadonlyMap<true>): Entry[] | undefined;
+    function toHighlightSpan(entry: Entry): {
+        fileName: string;
+        span: HighlightSpan;
+    };
+}
+/** Encapsulates the core find-all-references algorithm. */
+declare namespace ts.FindAllReferences.Core {
+    /** Core find-all-references algorithm. Handles special cases before delegating to `getReferencedSymbolsForSymbol`. */
+    function getReferencedSymbolsForNode(position: number, node: Node, program: Program, sourceFiles: ReadonlyArray<SourceFile>, cancellationToken: CancellationToken, options?: Options, sourceFilesSet?: ReadonlyMap<true>): SymbolAndEntries[] | undefined;
+    /** Used as a quick check for whether a symbol is used at all in a file (besides its definition). */
+    function isSymbolReferencedInFile(definition: Identifier, checker: TypeChecker, sourceFile: SourceFile): boolean;
+    function eachSymbolReferenceInFile<T>(definition: Identifier, checker: TypeChecker, sourceFile: SourceFile, cb: (token: Identifier) => T): T | undefined;
+    /**
+     * Given an initial searchMeaning, extracted from a location, widen the search scope based on the declarations
+     * of the corresponding symbol. e.g. if we are searching for "Foo" in value position, but "Foo" references a class
+     * then we need to widen the search to include type positions as well.
+     * On the contrary, if we are searching for "Bar" in type position and we trace bar to an interface, and an uninstantiated
+     * module, we want to keep the search limited to only types, as the two declarations (interface and uninstantiated module)
+     * do not intersect in any of the three spaces.
+     */
+    function getIntersectingMeaningFromDeclarations(node: Node, symbol: Symbol): SemanticMeaning;
+    function getReferenceEntriesForShorthandPropertyAssignment(node: Node, checker: TypeChecker, addReference: (node: Node) => void): void;
+}
+declare namespace ts {
+    function getEditsForFileRename(program: Program, oldFileOrDirPath: string, newFileOrDirPath: string, host: LanguageServiceHost, formatContext: formatting.FormatContext, preferences: UserPreferences): ReadonlyArray<FileTextChanges>;
+}
+declare namespace ts.GoToDefinition {
+    function getDefinitionAtPosition(program: Program, sourceFile: SourceFile, position: number): DefinitionInfo[] | undefined;
+    function getReferenceAtPosition(sourceFile: SourceFile, position: number, program: Program): {
+        fileName: string;
+        file: SourceFile;
+    } | undefined;
+    function getTypeDefinitionAtPosition(typeChecker: TypeChecker, sourceFile: SourceFile, position: number): DefinitionInfo[] | undefined;
+    function getDefinitionAndBoundSpan(program: Program, sourceFile: SourceFile, position: number): DefinitionInfoAndBoundSpan | undefined;
+    function findReferenceInPosition(refs: ReadonlyArray<FileReference>, pos: number): FileReference | undefined;
+}
+declare namespace ts.JsDoc {
+    function getJsDocCommentsFromDeclarations(declarations: ReadonlyArray<Declaration>): SymbolDisplayPart[];
+    function getJsDocTagsFromDeclarations(declarations?: Declaration[]): JSDocTagInfo[];
+    function getJSDocTagNameCompletions(): CompletionEntry[];
+    const getJSDocTagNameCompletionDetails: typeof getJSDocTagCompletionDetails;
+    function getJSDocTagCompletions(): CompletionEntry[];
+    function getJSDocTagCompletionDetails(name: string): CompletionEntryDetails;
+    function getJSDocParameterNameCompletions(tag: JSDocParameterTag): CompletionEntry[];
+    function getJSDocParameterNameCompletionDetails(name: string): CompletionEntryDetails;
+    /**
+     * Checks if position points to a valid position to add JSDoc comments, and if so,
+     * returns the appropriate template. Otherwise returns an empty string.
+     * Valid positions are
+     *      - outside of comments, statements, and expressions, and
+     *      - preceding a:
+     *          - function/constructor/method declaration
+     *          - class declarations
+     *          - variable statements
+     *          - namespace declarations
+     *          - interface declarations
+     *          - method signatures
+     *          - type alias declarations
+     *
+     * Hosts should ideally check that:
+     * - The line is all whitespace up to 'position' before performing the insertion.
+     * - If the keystroke sequence "/\*\*" induced the call, we also check that the next
+     * non-whitespace character is '*', which (approximately) indicates whether we added
+     * the second '*' to complete an existing (JSDoc) comment.
+     * @param fileName The file in which to perform the check.
+     * @param position The (character-indexed) position in the file where the check should
+     * be performed.
+     */
+    function getDocCommentTemplateAtPosition(newLine: string, sourceFile: SourceFile, position: number): TextInsertion | undefined;
+}
+declare namespace ts.NavigateTo {
+    function getNavigateToItems(sourceFiles: ReadonlyArray<SourceFile>, checker: TypeChecker, cancellationToken: CancellationToken, searchValue: string, maxResultCount: number | undefined, excludeDtsFiles: boolean): NavigateToItem[];
+}
+declare namespace ts.NavigationBar {
+    function getNavigationBarItems(sourceFile: SourceFile, cancellationToken: CancellationToken): NavigationBarItem[];
+    function getNavigationTree(sourceFile: SourceFile, cancellationToken: CancellationToken): NavigationTree;
+}
+declare namespace ts.OrganizeImports {
+    /**
+     * Organize imports by:
+     *   1) Removing unused imports
+     *   2) Coalescing imports from the same module
+     *   3) Sorting imports
+     */
+    function organizeImports(sourceFile: SourceFile, formatContext: formatting.FormatContext, host: LanguageServiceHost, program: Program, _preferences: UserPreferences): FileTextChanges[];
+    /**
+     * @param importGroup a list of ImportDeclarations, all with the same module name.
+     */
+    function coalesceImports(importGroup: ReadonlyArray<ImportDeclaration>): ReadonlyArray<ImportDeclaration>;
+    /**
+     * @param exportGroup a list of ExportDeclarations, all with the same module name.
+     */
+    function coalesceExports(exportGroup: ReadonlyArray<ExportDeclaration>): ReadonlyArray<ExportDeclaration>;
+    function compareModuleSpecifiers(m1: Expression, m2: Expression): Comparison;
+}
+declare namespace ts.OutliningElementsCollector {
+    function collectElements(sourceFile: SourceFile, cancellationToken: CancellationToken): OutliningSpan[];
+}
+declare namespace ts {
+    enum PatternMatchKind {
+        exact = 0,
+        prefix = 1,
+        substring = 2,
+        camelCase = 3
+    }
+    interface PatternMatch {
+        kind: PatternMatchKind;
+        isCaseSensitive: boolean;
+    }
+    interface PatternMatcher {
+        getMatchForLastSegmentOfPattern(candidate: string): PatternMatch | undefined;
+        getFullMatch(candidateContainers: ReadonlyArray<string>, candidate: string): PatternMatch | undefined;
+        patternContainsDots: boolean;
+    }
+    function createPatternMatcher(pattern: string): PatternMatcher | undefined;
+    function breakIntoCharacterSpans(identifier: string): TextSpan[];
+    function breakIntoWordSpans(identifier: string): TextSpan[];
 }
 declare namespace ts {
     function preProcessFile(sourceText: string, readImportFiles?: boolean, detectJavaScriptImports?: boolean): PreProcessedFileInfo;
 }
+declare namespace ts.Rename {
+    function getRenameInfo(typeChecker: TypeChecker, defaultLibFileName: string, getCanonicalFileName: GetCanonicalFileName, sourceFile: SourceFile, position: number): RenameInfo;
+}
+declare namespace ts.SignatureHelp {
+    function getSignatureHelpItems(program: Program, sourceFile: SourceFile, position: number, cancellationToken: CancellationToken): SignatureHelpItems | undefined;
+    interface ArgumentInfoForCompletions {
+        readonly invocation: CallLikeExpression;
+        readonly argumentIndex: number;
+        readonly argumentCount: number;
+    }
+    function getArgumentInfoForCompletions(node: Node, position: number, sourceFile: SourceFile): ArgumentInfoForCompletions | undefined;
+}
+declare namespace ts {
+    function computeSuggestionDiagnostics(sourceFile: SourceFile, program: Program, cancellationToken: CancellationToken): DiagnosticWithLocation[];
+}
+declare namespace ts.SymbolDisplay {
+    function getSymbolKind(typeChecker: TypeChecker, symbol: Symbol, location: Node): ScriptElementKind;
+    function getSymbolModifiers(symbol: Symbol): string;
+    interface SymbolDisplayPartsDocumentationAndSymbolKind {
+        displayParts: SymbolDisplayPart[];
+        documentation: SymbolDisplayPart[];
+        symbolKind: ScriptElementKind;
+        tags: JSDocTagInfo[] | undefined;
+    }
+    function getSymbolDisplayPartsDocumentationAndSymbolKind(typeChecker: TypeChecker, symbol: Symbol, sourceFile: SourceFile, enclosingDeclaration: Node | undefined, location: Node, semanticMeaning?: SemanticMeaning, alias?: Symbol): SymbolDisplayPartsDocumentationAndSymbolKind;
+}
 declare namespace ts {
     interface TranspileOptions {
         compilerOptions?: CompilerOptions;
@@ -5318,10 +11162,542 @@ declare namespace ts {
     }
     function transpileModule(input: string, transpileOptions: TranspileOptions): TranspileOutput;
     function transpile(input: string, compilerOptions?: CompilerOptions, fileName?: string, diagnostics?: Diagnostic[], moduleName?: string): string;
+    /** JS users may pass in string values for enum compiler options (such as ModuleKind), so convert. */
+    function fixupCompilerOptions(options: CompilerOptions, diagnostics: Diagnostic[]): CompilerOptions;
+}
+declare namespace ts.formatting {
+    enum FormattingRequestKind {
+        FormatDocument = 0,
+        FormatSelection = 1,
+        FormatOnEnter = 2,
+        FormatOnSemicolon = 3,
+        FormatOnOpeningCurlyBrace = 4,
+        FormatOnClosingCurlyBrace = 5
+    }
+    class FormattingContext {
+        readonly sourceFile: SourceFileLike;
+        formattingRequestKind: FormattingRequestKind;
+        options: FormatCodeSettings;
+        currentTokenSpan: TextRangeWithKind;
+        nextTokenSpan: TextRangeWithKind;
+        contextNode: Node;
+        currentTokenParent: Node;
+        nextTokenParent: Node;
+        private contextNodeAllOnSameLine;
+        private nextNodeAllOnSameLine;
+        private tokensAreOnSameLine;
+        private contextNodeBlockIsOnOneLine;
+        private nextNodeBlockIsOnOneLine;
+        constructor(sourceFile: SourceFileLike, formattingRequestKind: FormattingRequestKind, options: FormatCodeSettings);
+        updateContext(currentRange: TextRangeWithKind, currentTokenParent: Node, nextRange: TextRangeWithKind, nextTokenParent: Node, commonParent: Node): void;
+        ContextNodeAllOnSameLine(): boolean;
+        NextNodeAllOnSameLine(): boolean;
+        TokensAreOnSameLine(): boolean;
+        ContextNodeBlockIsOnOneLine(): boolean;
+        NextNodeBlockIsOnOneLine(): boolean;
+        private NodeIsOnOneLine;
+        private BlockIsOnOneLine;
+    }
+}
+declare namespace ts.formatting {
+    interface FormattingScanner {
+        advance(): void;
+        isOnToken(): boolean;
+        readTokenInfo(n: Node): TokenInfo;
+        getCurrentLeadingTrivia(): TextRangeWithKind[] | undefined;
+        lastTrailingTriviaWasNewLine(): boolean;
+        skipToEndOf(node: Node): void;
+    }
+    function getFormattingScanner<T>(text: string, languageVariant: LanguageVariant, startPos: number, endPos: number, cb: (scanner: FormattingScanner) => T): T;
+}
+declare namespace ts.formatting {
+    interface Rule {
+        readonly debugName: string;
+        readonly context: ReadonlyArray<ContextPredicate>;
+        readonly action: RuleAction;
+        readonly flags: RuleFlags;
+    }
+    type ContextPredicate = (context: FormattingContext) => boolean;
+    const anyContext: ReadonlyArray<ContextPredicate>;
+    enum RuleAction {
+        Ignore = 1,
+        Space = 2,
+        NewLine = 4,
+        Delete = 8
+    }
+    enum RuleFlags {
+        None = 0,
+        CanDeleteNewLines = 1
+    }
+    interface TokenRange {
+        readonly tokens: ReadonlyArray<SyntaxKind>;
+        readonly isSpecific: boolean;
+    }
+}
+declare namespace ts.formatting {
+    interface RuleSpec {
+        readonly leftTokenRange: TokenRange;
+        readonly rightTokenRange: TokenRange;
+        readonly rule: Rule;
+    }
+    function getAllRules(): RuleSpec[];
+}
+declare namespace ts.formatting {
+    function getFormatContext(options: FormatCodeSettings): FormatContext;
+    type RulesMap = (context: FormattingContext) => Rule | undefined;
+}
+declare namespace ts.formatting {
+    interface FormatContext {
+        readonly options: FormatCodeSettings;
+        readonly getRule: RulesMap;
+    }
+    interface TextRangeWithKind extends TextRange {
+        kind: SyntaxKind;
+    }
+    interface TextRangeWithTriviaKind extends TextRange {
+        kind: TriviaKind;
+    }
+    interface TokenInfo {
+        leadingTrivia: TextRangeWithTriviaKind[] | undefined;
+        token: TextRangeWithKind;
+        trailingTrivia: TextRangeWithTriviaKind[] | undefined;
+    }
+    function formatOnEnter(position: number, sourceFile: SourceFile, formatContext: FormatContext): TextChange[];
+    function formatOnSemicolon(position: number, sourceFile: SourceFile, formatContext: FormatContext): TextChange[];
+    function formatOnOpeningCurly(position: number, sourceFile: SourceFile, formatContext: FormatContext): TextChange[];
+    function formatOnClosingCurly(position: number, sourceFile: SourceFile, formatContext: FormatContext): TextChange[];
+    function formatDocument(sourceFile: SourceFile, formatContext: FormatContext): TextChange[];
+    function formatSelection(start: number, end: number, sourceFile: SourceFile, formatContext: FormatContext): TextChange[];
+    function formatNodeGivenIndentation(node: Node, sourceFileLike: SourceFileLike, languageVariant: LanguageVariant, initialIndentation: number, delta: number, formatContext: FormatContext): TextChange[];
+    /**
+     * @param precedingToken pass `null` if preceding token was already computed and result was `undefined`.
+     */
+    function getRangeOfEnclosingComment(sourceFile: SourceFile, position: number, onlyMultiLine: boolean, precedingToken?: Node | null, // tslint:disable-line:no-null-keyword
+    tokenAtPosition?: Node, predicate?: (c: CommentRange) => boolean): CommentRange | undefined;
+    function getIndentationString(indentation: number, options: EditorSettings): string;
+}
+declare namespace ts.formatting {
+    namespace SmartIndenter {
+        /**
+         * @param assumeNewLineBeforeCloseBrace
+         * `false` when called on text from a real source file.
+         * `true` when we need to assume `position` is on a newline.
+         *
+         * This is useful for codefixes. Consider
+         * ```
+         * function f() {
+         * |}
+         * ```
+         * with `position` at `|`.
+         *
+         * When inserting some text after an open brace, we would like to get indentation as if a newline was already there.
+         * By default indentation at `position` will be 0 so 'assumeNewLineBeforeCloseBrace' overrides this behavior.
+         */
+        function getIndentation(position: number, sourceFile: SourceFile, options: EditorSettings, assumeNewLineBeforeCloseBrace?: boolean): number;
+        function getIndentationForNode(n: Node, ignoreActualIndentationRange: TextRange, sourceFile: SourceFile, options: EditorSettings): number;
+        function getBaseIndentation(options: EditorSettings): number;
+        function isArgumentAndStartLineOverlapsExpressionBeingCalled(parent: Node, child: Node, childStartLine: number, sourceFile: SourceFileLike): boolean;
+        function childStartsOnTheSameLineWithElseInIfStatement(parent: Node, child: TextRangeWithKind, childStartLine: number, sourceFile: SourceFileLike): boolean;
+        function getContainingList(node: Node, sourceFile: SourceFile): NodeArray<Node> | undefined;
+        /**
+         * Character is the actual index of the character since the beginning of the line.
+         * Column - position of the character after expanding tabs to spaces.
+         * "0\t2$"
+         * value of 'character' for '$' is 3
+         * value of 'column' for '$' is 6 (assuming that tab size is 4)
+         */
+        function findFirstNonWhitespaceCharacterAndColumn(startPos: number, endPos: number, sourceFile: SourceFileLike, options: EditorSettings): {
+            column: number;
+            character: number;
+        };
+        function findFirstNonWhitespaceColumn(startPos: number, endPos: number, sourceFile: SourceFileLike, options: EditorSettings): number;
+        function nodeWillIndentChild(settings: FormatCodeSettings, parent: TextRangeWithKind, child: TextRangeWithKind | undefined, sourceFile: SourceFileLike | undefined, indentByDefault: boolean): boolean;
+        /**
+         * True when the parent node should indent the given child by an explicit rule.
+         * @param isNextChild If true, we are judging indent of a hypothetical child *after* this one, not the current child.
+         */
+        function shouldIndentChildNode(settings: FormatCodeSettings, parent: TextRangeWithKind, child?: Node, sourceFile?: SourceFileLike, isNextChild?: boolean): boolean;
+    }
+}
+declare namespace ts.textChanges {
+    interface ConfigurableStart {
+        /** True to use getStart() (NB, not getFullStart()) without adjustment. */
+        useNonAdjustedStartPosition?: boolean;
+    }
+    interface ConfigurableEnd {
+        /** True to use getEnd() without adjustment. */
+        useNonAdjustedEndPosition?: boolean;
+    }
+    enum Position {
+        FullStart = 0,
+        Start = 1
+    }
+    /**
+     * Usually node.pos points to a position immediately after the previous token.
+     * If this position is used as a beginning of the span to remove - it might lead to removing the trailing trivia of the previous node, i.e:
+     * const x; // this is x
+     *        ^ - pos for the next variable declaration will point here
+     * const y; // this is y
+     *        ^ - end for previous variable declaration
+     * Usually leading trivia of the variable declaration 'y' should not include trailing trivia (whitespace, comment 'this is x' and newline) from the preceding
+     * variable declaration and trailing trivia for 'y' should include (whitespace, comment 'this is y', newline).
+     * By default when removing nodes we adjust start and end positions to respect specification of the trivia above.
+     * If pos\end should be interpreted literally 'useNonAdjustedStartPosition' or 'useNonAdjustedEndPosition' should be set to true
+     */
+    interface ConfigurableStartEnd extends ConfigurableStart, ConfigurableEnd {
+    }
+    const useNonAdjustedPositions: ConfigurableStartEnd;
+    interface InsertNodeOptions {
+        /**
+         * Text to be inserted before the new node
+         */
+        prefix?: string;
+        /**
+         * Text to be inserted after the new node
+         */
+        suffix?: string;
+        /**
+         * Text of inserted node will be formatted with this indentation, otherwise indentation will be inferred from the old node
+         */
+        indentation?: number;
+        /**
+         * Text of inserted node will be formatted with this delta, otherwise delta will be inferred from the new node kind
+         */
+        delta?: number;
+        /**
+         * Do not trim leading white spaces in the edit range
+         */
+        preserveLeadingWhitespace?: boolean;
+    }
+    interface ReplaceWithMultipleNodesOptions extends InsertNodeOptions {
+        readonly joiner?: string;
+    }
+    interface ChangeNodeOptions extends ConfigurableStartEnd, InsertNodeOptions {
+    }
+    interface TextChangesContext {
+        host: LanguageServiceHost;
+        formatContext: formatting.FormatContext;
+    }
+    type TypeAnnotatable = SignatureDeclaration | VariableDeclaration | ParameterDeclaration | PropertyDeclaration | PropertySignature;
+    class ChangeTracker {
+        private readonly newLineCharacter;
+        private readonly formatContext;
+        private readonly changes;
+        private readonly newFiles;
+        private readonly deletedNodesInLists;
+        private readonly classesWithNodesInsertedAtStart;
+        static fromContext(context: TextChangesContext): ChangeTracker;
+        static with(context: TextChangesContext, cb: (tracker: ChangeTracker) => void): FileTextChanges[];
+        /** Public for tests only. Other callers should use `ChangeTracker.with`. */
+        constructor(newLineCharacter: string, formatContext: formatting.FormatContext);
+        deleteRange(sourceFile: SourceFile, range: TextRange): this;
+        /** Warning: This deletes comments too. See `copyComments` in `convertFunctionToEs6Class`. */
+        deleteNode(sourceFile: SourceFile, node: Node, options?: ConfigurableStartEnd): this;
+        deleteNodeRange(sourceFile: SourceFile, startNode: Node, endNode: Node, options?: ConfigurableStartEnd): this;
+        deleteNodeRangeExcludingEnd(sourceFile: SourceFile, startNode: Node, afterEndNode: Node | undefined, options?: ConfigurableStartEnd): void;
+        deleteNodeInList(sourceFile: SourceFile, node: Node): this;
+        replaceRange(sourceFile: SourceFile, range: TextRange, newNode: Node, options?: InsertNodeOptions): this;
+        replaceNode(sourceFile: SourceFile, oldNode: Node, newNode: Node, options?: ChangeNodeOptions): this;
+        replaceNodeRange(sourceFile: SourceFile, startNode: Node, endNode: Node, newNode: Node, options?: ChangeNodeOptions): void;
+        private replaceRangeWithNodes;
+        replaceNodeWithNodes(sourceFile: SourceFile, oldNode: Node, newNodes: ReadonlyArray<Node>, options?: ChangeNodeOptions): this;
+        replaceNodeRangeWithNodes(sourceFile: SourceFile, startNode: Node, endNode: Node, newNodes: ReadonlyArray<Node>, options?: ReplaceWithMultipleNodesOptions & ConfigurableStartEnd): this;
+        private nextCommaToken;
+        replacePropertyAssignment(sourceFile: SourceFile, oldNode: PropertyAssignment, newNode: PropertyAssignment): this;
+        private insertNodeAt;
+        private insertNodesAt;
+        insertNodeAtTopOfFile(sourceFile: SourceFile, newNode: Statement, blankLineBetween: boolean): void;
+        insertNodeBefore(sourceFile: SourceFile, before: Node, newNode: Node, blankLineBetween?: boolean): void;
+        insertModifierBefore(sourceFile: SourceFile, modifier: SyntaxKind, before: Node): void;
+        insertCommentBeforeLine(sourceFile: SourceFile, lineNumber: number, position: number, commentText: string): void;
+        replaceRangeWithText(sourceFile: SourceFile, range: TextRange, text: string): void;
+        private insertText;
+        /** Prefer this over replacing a node with another that has a type annotation, as it avoids reformatting the other parts of the node. */
+        tryInsertTypeAnnotation(sourceFile: SourceFile, node: TypeAnnotatable, type: TypeNode): void;
+        insertTypeParameters(sourceFile: SourceFile, node: SignatureDeclaration, typeParameters: ReadonlyArray<TypeParameterDeclaration>): void;
+        private getOptionsForInsertNodeBefore;
+        insertNodeAtConstructorStart(sourceFile: SourceFile, ctr: ConstructorDeclaration, newStatement: Statement): void;
+        insertNodeAtConstructorEnd(sourceFile: SourceFile, ctr: ConstructorDeclaration, newStatement: Statement): void;
+        private replaceConstructorBody;
+        insertNodeAtEndOfScope(sourceFile: SourceFile, scope: Node, newNode: Node): void;
+        insertNodeAtClassStart(sourceFile: SourceFile, cls: ClassLikeDeclaration, newElement: ClassElement): void;
+        private getInsertNodeAtClassStartPrefixSuffix;
+        insertNodeAfterComma(sourceFile: SourceFile, after: Node, newNode: Node): void;
+        insertNodeAfter(sourceFile: SourceFile, after: Node, newNode: Node): void;
+        insertNodesAfter(sourceFile: SourceFile, after: Node, newNodes: ReadonlyArray<Node>): void;
+        private insertNodeAfterWorker;
+        private getInsertNodeAfterOptions;
+        private getInsertNodeAfterOptionsWorker;
+        insertName(sourceFile: SourceFile, node: FunctionExpression | ClassExpression | ArrowFunction, name: string): void;
+        insertExportModifier(sourceFile: SourceFile, node: DeclarationStatement | VariableStatement): void;
+        /**
+         * This function should be used to insert nodes in lists when nodes don't carry separators as the part of the node range,
+         * i.e. arguments in arguments lists, parameters in parameter lists etc.
+         * Note that separators are part of the node in statements and class elements.
+         */
+        insertNodeInListAfter(sourceFile: SourceFile, after: Node, newNode: Node, containingList?: NodeArray<Node> | undefined): this;
+        private finishClassesWithNodesInsertedAtStart;
+        private finishTrailingCommaAfterDeletingNodesInList;
+        /**
+         * Note: after calling this, the TextChanges object must be discarded!
+         * @param validate only for tests
+         *    The reason we must validate as part of this method is that `getNonFormattedText` changes the node's positions,
+         *    so we can only call this once and can't get the non-formatted text separately.
+         */
+        getChanges(validate?: ValidateNonFormattedText): FileTextChanges[];
+        createNewFile(oldFile: SourceFile, fileName: string, statements: ReadonlyArray<Statement>): void;
+    }
+    type ValidateNonFormattedText = (node: Node, text: string) => void;
+    function applyChanges(text: string, changes: TextChange[]): string;
+    function isValidLocationToAddComment(sourceFile: SourceFile, position: number): boolean;
+}
+declare namespace ts {
+    interface CodeFixRegistration {
+        errorCodes: number[];
+        getCodeActions(context: CodeFixContext): CodeFixAction[] | undefined;
+        fixIds?: string[];
+        getAllCodeActions?(context: CodeFixAllContext): CombinedCodeActions;
+    }
+    interface CodeFixContextBase extends textChanges.TextChangesContext {
+        sourceFile: SourceFile;
+        program: Program;
+        cancellationToken: CancellationToken;
+        preferences: UserPreferences;
+    }
+    interface CodeFixAllContext extends CodeFixContextBase {
+        fixId: {};
+    }
+    interface CodeFixContext extends CodeFixContextBase {
+        errorCode: number;
+        span: TextSpan;
+    }
+    namespace codefix {
+        type DiagnosticAndArguments = DiagnosticMessage | [DiagnosticMessage, string] | [DiagnosticMessage, string, string];
+        function createCodeFixActionNoFixId(fixName: string, changes: FileTextChanges[], description: DiagnosticAndArguments): CodeFixAction;
+        function createCodeFixAction(fixName: string, changes: FileTextChanges[], description: DiagnosticAndArguments, fixId: {}, fixAllDescription: DiagnosticAndArguments, command?: CodeActionCommand): CodeFixAction;
+        function registerCodeFix(reg: CodeFixRegistration): void;
+        function getSupportedErrorCodes(): string[];
+        function getFixes(context: CodeFixContext): CodeFixAction[];
+        function getAllFixes(context: CodeFixAllContext): CombinedCodeActions;
+        function createFileTextChanges(fileName: string, textChanges: TextChange[]): FileTextChanges;
+        function codeFixAll(context: CodeFixAllContext, errorCodes: number[], use: (changes: textChanges.ChangeTracker, error: DiagnosticWithLocation, commands: Push<CodeActionCommand>) => void): CombinedCodeActions;
+    }
+}
+declare namespace ts {
+    interface Refactor {
+        /** Compute the associated code actions */
+        getEditsForAction(context: RefactorContext, actionName: string): RefactorEditInfo | undefined;
+        /** Compute (quickly) which actions are available here */
+        getAvailableActions(context: RefactorContext): ApplicableRefactorInfo[] | undefined;
+    }
+    interface RefactorContext extends textChanges.TextChangesContext {
+        file: SourceFile;
+        startPosition: number;
+        endPosition?: number;
+        program: Program;
+        cancellationToken?: CancellationToken;
+        preferences: UserPreferences;
+    }
+    namespace refactor {
+        /** @param name An unique code associated with each refactor. Does not have to be human-readable. */
+        function registerRefactor(name: string, refactor: Refactor): void;
+        function getApplicableRefactors(context: RefactorContext): ApplicableRefactorInfo[];
+        function getEditsForRefactor(context: RefactorContext, refactorName: string, actionName: string): RefactorEditInfo | undefined;
+    }
+    function getRefactorContextSpan({ startPosition, endPosition }: RefactorContext): TextSpan;
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+    type DeclarationWithType = FunctionLikeDeclaration | VariableDeclaration | PropertySignature | PropertyDeclaration;
+    function parameterShouldGetTypeFromJSDoc(node: Node): node is DeclarationWithType;
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+    function getImportCompletionAction(exportedSymbol: Symbol, moduleSymbol: Symbol, sourceFile: SourceFile, symbolName: string, host: LanguageServiceHost, program: Program, checker: TypeChecker, compilerOptions: CompilerOptions, allSourceFiles: ReadonlyArray<SourceFile>, formatContext: formatting.FormatContext, getCanonicalFileName: GetCanonicalFileName, symbolToken: Node | undefined, preferences: UserPreferences): {
+        readonly moduleSpecifier: string;
+        readonly codeAction: CodeAction;
+    };
+    function forEachExternalModuleToImportFrom(checker: TypeChecker, from: SourceFile, allSourceFiles: ReadonlyArray<SourceFile>, cb: (module: Symbol) => void): void;
+    function moduleSymbolToValidIdentifier(moduleSymbol: Symbol, target: ScriptTarget): string;
+    function moduleSpecifierToValidIdentifier(moduleSpecifier: string, target: ScriptTarget): string;
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+    /**
+     * Finds members of the resolved type that are missing in the class pointed to by class decl
+     * and generates source code for the missing members.
+     * @param possiblyMissingSymbols The collection of symbols to filter and then get insertions for.
+     * @returns Empty string iff there are no member insertions.
+     */
+    function createMissingMemberNodes(classDeclaration: ClassLikeDeclaration, possiblyMissingSymbols: ReadonlyArray<Symbol>, checker: TypeChecker, preferences: UserPreferences, out: (node: ClassElement) => void): void;
+    function createMethodFromCallExpression({ typeArguments, arguments: args, parent: parent }: CallExpression, methodName: string, inJs: boolean, makeStatic: boolean, preferences: UserPreferences): MethodDeclaration;
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.codefix {
+}
+declare namespace ts.refactor.generateGetAccessorAndSetAccessor {
+}
+declare namespace ts.refactor.extractSymbol {
+    /**
+     * Compute the associated code actions
+     * Exported for tests.
+     */
+    function getAvailableActions(context: RefactorContext): ApplicableRefactorInfo[] | undefined;
+    function getEditsForAction(context: RefactorContext, actionName: string): RefactorEditInfo | undefined;
+    namespace Messages {
+        const cannotExtractRange: DiagnosticMessage;
+        const cannotExtractImport: DiagnosticMessage;
+        const cannotExtractSuper: DiagnosticMessage;
+        const cannotExtractEmpty: DiagnosticMessage;
+        const expressionExpected: DiagnosticMessage;
+        const uselessConstantType: DiagnosticMessage;
+        const statementOrExpressionExpected: DiagnosticMessage;
+        const cannotExtractRangeContainingConditionalBreakOrContinueStatements: DiagnosticMessage;
+        const cannotExtractRangeContainingConditionalReturnStatement: DiagnosticMessage;
+        const cannotExtractRangeContainingLabeledBreakOrContinueStatementWithTargetOutsideOfTheRange: DiagnosticMessage;
+        const cannotExtractRangeThatContainsWritesToReferencesLocatedOutsideOfTheTargetRangeInGenerators: DiagnosticMessage;
+        const typeWillNotBeVisibleInTheNewScope: DiagnosticMessage;
+        const functionWillNotBeVisibleInTheNewScope: DiagnosticMessage;
+        const cannotExtractIdentifier: DiagnosticMessage;
+        const cannotExtractExportedEntity: DiagnosticMessage;
+        const cannotWriteInExpression: DiagnosticMessage;
+        const cannotExtractReadonlyPropertyInitializerOutsideConstructor: DiagnosticMessage;
+        const cannotExtractAmbientBlock: DiagnosticMessage;
+        const cannotAccessVariablesFromNestedScopes: DiagnosticMessage;
+        const cannotExtractToOtherFunctionLike: DiagnosticMessage;
+        const cannotExtractToJSClass: DiagnosticMessage;
+        const cannotExtractToExpressionArrowFunction: DiagnosticMessage;
+    }
+    enum RangeFacts {
+        None = 0,
+        HasReturn = 1,
+        IsGenerator = 2,
+        IsAsyncFunction = 4,
+        UsesThis = 8,
+        /**
+         * The range is in a function which needs the 'static' modifier in a class
+         */
+        InStaticRegion = 16
+    }
+    /**
+     * Represents an expression or a list of statements that should be extracted with some extra information
+     */
+    interface TargetRange {
+        readonly range: Expression | Statement[];
+        readonly facts: RangeFacts;
+        /**
+         * A list of symbols that are declared in the selected range which are visible in the containing lexical scope
+         * Used to ensure we don't turn something used outside the range free (or worse, resolve to a different entity).
+         */
+        readonly declarations: Symbol[];
+    }
+    /**
+     * Result of 'getRangeToExtract' operation: contains either a range or a list of errors
+     */
+    type RangeToExtract = {
+        readonly targetRange?: never;
+        readonly errors: ReadonlyArray<Diagnostic>;
+    } | {
+        readonly targetRange: TargetRange;
+        readonly errors?: never;
+    };
+    /**
+     * getRangeToExtract takes a span inside a text file and returns either an expression or an array
+     * of statements representing the minimum set of nodes needed to extract the entire span. This
+     * process may fail, in which case a set of errors is returned instead (these are currently
+     * not shown to the user, but can be used by us diagnostically)
+     */
+    function getRangeToExtract(sourceFile: SourceFile, span: TextSpan): RangeToExtract;
+}
+declare namespace ts.refactor.generateGetAccessorAndSetAccessor {
+}
+declare namespace ts.refactor {
+}
+declare namespace ts.refactor.addOrRemoveBracesToArrowFunction {
+}
+declare namespace ts.sourcemaps {
+    interface SourceMapData {
+        version?: number;
+        file?: string;
+        sourceRoot?: string;
+        sources: string[];
+        sourcesContent?: string[];
+        names?: string[];
+        mappings: string;
+    }
+    interface SourceMappableLocation {
+        fileName: string;
+        position: number;
+    }
+    interface SourceMapper {
+        getOriginalPosition(input: SourceMappableLocation): SourceMappableLocation;
+        getGeneratedPosition(input: SourceMappableLocation): SourceMappableLocation;
+    }
+    const identitySourceMapper: {
+        getOriginalPosition: typeof identity;
+        getGeneratedPosition: typeof identity;
+    };
+    interface SourceMapDecodeHost {
+        readFile(path: string): string | undefined;
+        fileExists(path: string): boolean;
+        getCanonicalFileName(path: string): string;
+        log(text: string): void;
+    }
+    function decode(host: SourceMapDecodeHost, mapPath: string, map: SourceMapData, program?: Program, fallbackCache?: SourceFileLikeCache): SourceMapper;
 }
 declare namespace ts {
     /** The version of the language service API */
     const servicesVersion = "0.8";
+    interface DisplayPartsSymbolWriter extends EmitTextWriter {
+        displayParts(): SymbolDisplayPart[];
+    }
+    function toEditorSettings(options: FormatCodeOptions | FormatCodeSettings): FormatCodeSettings;
     function toEditorSettings(options: EditorOptions | EditorSettings): EditorSettings;
     function displayPartsToString(displayParts: SymbolDisplayPart[] | undefined): string;
     function getDefaultCompilerOptions(): CompilerOptions;
@@ -5329,7 +11705,31 @@ declare namespace ts {
     function createLanguageServiceSourceFile(fileName: string, scriptSnapshot: IScriptSnapshot, scriptTarget: ScriptTarget, version: string, setNodeParents: boolean, scriptKind?: ScriptKind): SourceFile;
     let disableIncrementalParsing: boolean;
     function updateLanguageServiceSourceFile(sourceFile: SourceFile, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange | undefined, aggressiveChecks?: boolean): SourceFile;
+    /** A cancellation that throttles calls to the host */
+    class ThrottledCancellationToken implements CancellationToken {
+        private hostCancellationToken;
+        private readonly throttleWaitMilliseconds;
+        private lastCancellationCheckTime;
+        constructor(hostCancellationToken: HostCancellationToken, throttleWaitMilliseconds?: number);
+        isCancellationRequested(): boolean;
+        throwIfCancellationRequested(): void;
+    }
+    interface SourceFileLikeCache {
+        get(path: Path): SourceFileLike | undefined;
+    }
+    function createSourceFileLikeCache(host: {
+        readFile?: (path: string) => string | undefined;
+        fileExists?: (path: string) => boolean;
+    }): SourceFileLikeCache;
     function createLanguageService(host: LanguageServiceHost, documentRegistry?: DocumentRegistry, syntaxOnly?: boolean): LanguageService;
+    /** Names in the name table are escaped, so an identifier `__foo` will have a name table entry `___foo`. */
+    function getNameTable(sourceFile: SourceFile): UnderscoreEscapedMap<number>;
+    /**
+     * Returns the containing object literal property declaration given a possible name node, e.g. "a" in x = { "a": 1 }
+     */
+    function getContainingObjectLiteralElement(node: Node): ObjectLiteralElement | undefined;
+    function getPropertySymbolsFromContextualType(typeChecker: TypeChecker, node: ObjectLiteralElement): Symbol[];
+    function getPropertySymbolsFromType(type: Type, propName: PropertyName): Symbol[] | undefined;
     /**
      * Get the path of the default library files (lib.d.ts) as distributed with the typescript
      * node package.
@@ -5337,6 +11737,12 @@ declare namespace ts {
      */
     function getDefaultLibFilePath(options: CompilerOptions): string;
 }
+declare namespace ts.BreakpointResolver {
+    /**
+     * Get the breakpoint span in given sourceFile
+     */
+    function spanInSourceFileAtLocation(sourceFile: SourceFile, position: number): TextSpan | undefined;
+}
 declare namespace ts {
     /**
      * Transform one or more nodes using the supplied transformers.
@@ -5346,6 +11752,278 @@ declare namespace ts {
      */
     function transform<T extends Node>(source: T | T[], transformers: TransformerFactory<T>[], compilerOptions?: CompilerOptions): TransformationResult<T>;
 }
+declare let debugObjectHost: {
+    CollectGarbage(): void;
+};
+declare namespace ts {
+    interface ScriptSnapshotShim {
+        /** Gets a portion of the script snapshot specified by [start, end). */
+        getText(start: number, end: number): string;
+        /** Gets the length of this script snapshot. */
+        getLength(): number;
+        /**
+         * Returns a JSON-encoded value of the type:
+         *   { span: { start: number; length: number }; newLength: number }
+         *
+         * Or undefined value if there was no change.
+         */
+        getChangeRange(oldSnapshot: ScriptSnapshotShim): string | undefined;
+        /** Releases all resources held by this script snapshot */
+        dispose?(): void;
+    }
+    interface Logger {
+        log(s: string): void;
+        trace(s: string): void;
+        error(s: string): void;
+    }
+    /** Public interface of the host of a language service shim instance. */
+    interface LanguageServiceShimHost extends Logger {
+        getCompilationSettings(): string;
+        /** Returns a JSON-encoded value of the type: string[] */
+        getScriptFileNames(): string;
+        getScriptKind?(fileName: string): ScriptKind;
+        getScriptVersion(fileName: string): string;
+        getScriptSnapshot(fileName: string): ScriptSnapshotShim;
+        getLocalizedDiagnosticMessages(): string;
+        getCancellationToken(): HostCancellationToken;
+        getCurrentDirectory(): string;
+        getDirectories(path: string): string;
+        getDefaultLibFileName(options: string): string;
+        getNewLine?(): string;
+        getProjectVersion?(): string;
+        useCaseSensitiveFileNames?(): boolean;
+        getTypeRootsVersion?(): number;
+        readDirectory(rootDir: string, extension: string, basePaths?: string, excludeEx?: string, includeFileEx?: string, includeDirEx?: string, depth?: number): string;
+        readFile(path: string, encoding?: string): string | undefined;
+        fileExists(path: string): boolean;
+        getModuleResolutionsForFile?(fileName: string): string;
+        getTypeReferenceDirectiveResolutionsForFile?(fileName: string): string;
+        directoryExists(directoryName: string): boolean;
+    }
+    /** Public interface of the core-services host instance used in managed side */
+    interface CoreServicesShimHost extends Logger {
+        directoryExists(directoryName: string): boolean;
+        fileExists(fileName: string): boolean;
+        getCurrentDirectory(): string;
+        getDirectories(path: string): string;
+        /**
+         * Returns a JSON-encoded value of the type: string[]
+         *
+         * @param exclude A JSON encoded string[] containing the paths to exclude
+         *  when enumerating the directory.
+         */
+        readDirectory(rootDir: string, extension: string, basePaths?: string, excludeEx?: string, includeFileEx?: string, includeDirEx?: string, depth?: number): string;
+        /**
+         * Read arbitary text files on disk, i.e. when resolution procedure needs the content of 'package.json' to determine location of bundled typings for node modules
+         */
+        readFile(fileName: string): string | undefined;
+        realpath?(path: string): string;
+        trace(s: string): void;
+        useCaseSensitiveFileNames?(): boolean;
+    }
+    interface ShimsFileReference {
+        path: string;
+        position: number;
+        length: number;
+    }
+    /** Public interface of a language service instance shim. */
+    interface ShimFactory {
+        registerShim(shim: Shim): void;
+        unregisterShim(shim: Shim): void;
+    }
+    interface Shim {
+        dispose(_dummy: {}): void;
+    }
+    interface LanguageServiceShim extends Shim {
+        languageService: LanguageService;
+        dispose(_dummy: {}): void;
+        refresh(throwOnError: boolean): void;
+        cleanupSemanticCache(): void;
+        getSyntacticDiagnostics(fileName: string): string;
+        getSemanticDiagnostics(fileName: string): string;
+        getSuggestionDiagnostics(fileName: string): string;
+        getCompilerOptionsDiagnostics(): string;
+        getSyntacticClassifications(fileName: string, start: number, length: number): string;
+        getSemanticClassifications(fileName: string, start: number, length: number): string;
+        getEncodedSyntacticClassifications(fileName: string, start: number, length: number): string;
+        getEncodedSemanticClassifications(fileName: string, start: number, length: number): string;
+        getCompletionsAtPosition(fileName: string, position: number, preferences: UserPreferences | undefined): string;
+        getCompletionEntryDetails(fileName: string, position: number, entryName: string, formatOptions: string | undefined, source: string | undefined, preferences: UserPreferences | undefined): string;
+        getQuickInfoAtPosition(fileName: string, position: number): string;
+        getNameOrDottedNameSpan(fileName: string, startPos: number, endPos: number): string;
+        getBreakpointStatementAtPosition(fileName: string, position: number): string;
+        getSignatureHelpItems(fileName: string, position: number): string;
+        /**
+         * Returns a JSON-encoded value of the type:
+         * { canRename: boolean, localizedErrorMessage: string, displayName: string, fullDisplayName: string, kind: string, kindModifiers: string, triggerSpan: { start; length } }
+         */
+        getRenameInfo(fileName: string, position: number): string;
+        /**
+         * Returns a JSON-encoded value of the type:
+         * { fileName: string, textSpan: { start: number, length: number } }[]
+         */
+        findRenameLocations(fileName: string, position: number, findInStrings: boolean, findInComments: boolean): string;
+        /**
+         * Returns a JSON-encoded value of the type:
+         * { fileName: string; textSpan: { start: number; length: number}; kind: string; name: string; containerKind: string; containerName: string }
+         *
+         * Or undefined value if no definition can be found.
+         */
+        getDefinitionAtPosition(fileName: string, position: number): string;
+        getDefinitionAndBoundSpan(fileName: string, position: number): string;
+        /**
+         * Returns a JSON-encoded value of the type:
+         * { fileName: string; textSpan: { start: number; length: number}; kind: string; name: string; containerKind: string; containerName: string }
+         *
+         * Or undefined value if no definition can be found.
+         */
+        getTypeDefinitionAtPosition(fileName: string, position: number): string;
+        /**
+         * Returns a JSON-encoded value of the type:
+         * { fileName: string; textSpan: { start: number; length: number}; }[]
+         */
+        getImplementationAtPosition(fileName: string, position: number): string;
+        /**
+         * Returns a JSON-encoded value of the type:
+         * { fileName: string; textSpan: { start: number; length: number}; isWriteAccess: boolean, isDefinition?: boolean }[]
+         */
+        getReferencesAtPosition(fileName: string, position: number): string;
+        /**
+         * Returns a JSON-encoded value of the type:
+         * { definition: <encoded>; references: <encoded>[] }[]
+         */
+        findReferences(fileName: string, position: number): string;
+        /**
+         * @deprecated
+         * Returns a JSON-encoded value of the type:
+         * { fileName: string; textSpan: { start: number; length: number}; isWriteAccess: boolean }[]
+         */
+        getOccurrencesAtPosition(fileName: string, position: number): string;
+        /**
+         * Returns a JSON-encoded value of the type:
+         * { fileName: string; highlights: { start: number; length: number, isDefinition: boolean }[] }[]
+         *
+         * @param fileToSearch A JSON encoded string[] containing the file names that should be
+         *  considered when searching.
+         */
+        getDocumentHighlights(fileName: string, position: number, filesToSearch: string): string;
+        /**
+         * Returns a JSON-encoded value of the type:
+         * { name: string; kind: string; kindModifiers: string; containerName: string; containerKind: string; matchKind: string; fileName: string; textSpan: { start: number; length: number}; } [] = [];
+         */
+        getNavigateToItems(searchValue: string, maxResultCount?: number, fileName?: string): string;
+        /**
+         * Returns a JSON-encoded value of the type:
+         * { text: string; kind: string; kindModifiers: string; bolded: boolean; grayed: boolean; indent: number; spans: { start: number; length: number; }[]; childItems: <recursive use of this type>[] } [] = [];
+         */
+        getNavigationBarItems(fileName: string): string;
+        /** Returns a JSON-encoded value of the type ts.NavigationTree. */
+        getNavigationTree(fileName: string): string;
+        /**
+         * Returns a JSON-encoded value of the type:
+         * { textSpan: { start: number, length: number }; hintSpan: { start: number, length: number }; bannerText: string; autoCollapse: boolean } [] = [];
+         */
+        getOutliningSpans(fileName: string): string;
+        getTodoComments(fileName: string, todoCommentDescriptors: string): string;
+        getBraceMatchingAtPosition(fileName: string, position: number): string;
+        getIndentationAtPosition(fileName: string, position: number, options: string): string;
+        getFormattingEditsForRange(fileName: string, start: number, end: number, options: string): string;
+        getFormattingEditsForDocument(fileName: string, options: string): string;
+        getFormattingEditsAfterKeystroke(fileName: string, position: number, key: string, options: string): string;
+        /**
+         * Returns JSON-encoded value of the type TextInsertion.
+         */
+        getDocCommentTemplateAtPosition(fileName: string, position: number): string;
+        /**
+         * Returns JSON-encoded boolean to indicate whether we should support brace location
+         * at the current position.
+         * E.g. we don't want brace completion inside string-literals, comments, etc.
+         */
+        isValidBraceCompletionAtPosition(fileName: string, position: number, openingBrace: number): string;
+        /**
+         * Returns a JSON-encoded TextSpan | undefined indicating the range of the enclosing comment, if it exists.
+         */
+        getSpanOfEnclosingComment(fileName: string, position: number, onlyMultiLine: boolean): string;
+        getEmitOutput(fileName: string): string;
+        getEmitOutputObject(fileName: string): EmitOutput;
+    }
+    interface ClassifierShim extends Shim {
+        getEncodedLexicalClassifications(text: string, lexState: EndOfLineState, syntacticClassifierAbsent?: boolean): string;
+        getClassificationsForLine(text: string, lexState: EndOfLineState, syntacticClassifierAbsent?: boolean): string;
+    }
+    interface CoreServicesShim extends Shim {
+        getAutomaticTypeDirectiveNames(compilerOptionsJson: string): string;
+        getPreProcessedFileInfo(fileName: string, sourceText: IScriptSnapshot): string;
+        getTSConfigFileInfo(fileName: string, sourceText: IScriptSnapshot): string;
+        getDefaultCompilationSettings(): string;
+        discoverTypings(discoverTypingsJson: string): string;
+    }
+    class LanguageServiceShimHostAdapter implements LanguageServiceHost {
+        private shimHost;
+        private files;
+        private loggingEnabled;
+        private tracingEnabled;
+        resolveModuleNames: (moduleName: string[], containingFile: string) => ResolvedModuleFull[];
+        resolveTypeReferenceDirectives: (typeDirectiveNames: string[], containingFile: string) => ResolvedTypeReferenceDirective[];
+        directoryExists: (directoryName: string) => boolean;
+        constructor(shimHost: LanguageServiceShimHost);
+        log(s: string): void;
+        trace(s: string): void;
+        error(s: string): void;
+        getProjectVersion(): string;
+        getTypeRootsVersion(): number;
+        useCaseSensitiveFileNames(): boolean;
+        getCompilationSettings(): CompilerOptions;
+        getScriptFileNames(): string[];
+        getScriptSnapshot(fileName: string): IScriptSnapshot | undefined;
+        getScriptKind(fileName: string): ScriptKind;
+        getScriptVersion(fileName: string): string;
+        getLocalizedDiagnosticMessages(): any;
+        getCancellationToken(): HostCancellationToken;
+        getCurrentDirectory(): string;
+        getDirectories(path: string): string[];
+        getDefaultLibFileName(options: CompilerOptions): string;
+        readDirectory(path: string, extensions?: ReadonlyArray<string>, exclude?: string[], include?: string[], depth?: number): string[];
+        readFile(path: string, encoding?: string): string | undefined;
+        fileExists(path: string): boolean;
+    }
+    class CoreServicesShimHostAdapter implements ParseConfigHost, ModuleResolutionHost, JsTyping.TypingResolutionHost {
+        private shimHost;
+        directoryExists: (directoryName: string) => boolean;
+        realpath: (path: string) => string;
+        useCaseSensitiveFileNames: boolean;
+        constructor(shimHost: CoreServicesShimHost);
+        readDirectory(rootDir: string, extensions: ReadonlyArray<string>, exclude: ReadonlyArray<string>, include: ReadonlyArray<string>, depth?: number): string[];
+        fileExists(fileName: string): boolean;
+        readFile(fileName: string): string | undefined;
+        getDirectories(path: string): string[];
+    }
+    interface RealizedDiagnostic {
+        message: string;
+        start: number;
+        length: number;
+        category: string;
+        code: number;
+        reportsUnnecessary?: {};
+    }
+    function realizeDiagnostics(diagnostics: ReadonlyArray<Diagnostic>, newLine: string): RealizedDiagnostic[];
+    class TypeScriptServicesFactory implements ShimFactory {
+        private _shims;
+        private documentRegistry;
+        getServicesVersion(): string;
+        createLanguageServiceShim(host: LanguageServiceShimHost): LanguageServiceShim;
+        createClassifierShim(logger: Logger): ClassifierShim;
+        createCoreServicesShim(host: CoreServicesShimHost): CoreServicesShim;
+        close(): void;
+        registerShim(shim: Shim): void;
+        unregisterShim(shim: Shim): void;
+    }
+}
+declare namespace TypeScript.Services {
+    const TypeScriptServicesFactory: typeof ts.TypeScriptServicesFactory;
+}
+declare const toolsVersion = "3.0";
+//# sourceMappingURL=services.d.ts.map
 declare namespace ts.server {
     interface CompressedData {
         length: number;
@@ -5373,101 +12051,6 @@ declare namespace ts.server {
         trace?(s: string): void;
         require?(initialPath: string, moduleName: string): RequireResult;
     }
-    interface SortedReadonlyArray<T> extends ReadonlyArray<T> {
-        " __sortedArrayBrand": any;
-    }
-    interface TypingInstallerRequestWithProjectName {
-        readonly projectName: string;
-    }
-    interface DiscoverTypings extends TypingInstallerRequestWithProjectName {
-        readonly fileNames: string[];
-        readonly projectRootPath: Path;
-        readonly compilerOptions: CompilerOptions;
-        readonly typeAcquisition: TypeAcquisition;
-        readonly unresolvedImports: SortedReadonlyArray<string>;
-        readonly cachePath?: string;
-        readonly kind: "discover";
-    }
-    interface CloseProject extends TypingInstallerRequestWithProjectName {
-        readonly kind: "closeProject";
-    }
-    interface TypesRegistryRequest {
-        readonly kind: "typesRegistry";
-    }
-    interface InstallPackageRequest extends TypingInstallerRequestWithProjectName {
-        readonly kind: "installPackage";
-        readonly fileName: Path;
-        readonly packageName: string;
-        readonly projectRootPath: Path;
-    }
-    type ActionSet = "action::set";
-    type ActionInvalidate = "action::invalidate";
-    type ActionPackageInstalled = "action::packageInstalled";
-    type EventTypesRegistry = "event::typesRegistry";
-    type EventBeginInstallTypes = "event::beginInstallTypes";
-    type EventEndInstallTypes = "event::endInstallTypes";
-    type EventInitializationFailed = "event::initializationFailed";
-    interface TypingInstallerResponse {
-        readonly kind: ActionSet | ActionInvalidate | EventTypesRegistry | ActionPackageInstalled | EventBeginInstallTypes | EventEndInstallTypes | EventInitializationFailed;
-    }
-    interface PackageInstalledResponse extends ProjectResponse {
-        readonly kind: ActionPackageInstalled;
-        readonly success: boolean;
-        readonly message: string;
-    }
-    interface InitializationFailedResponse extends TypingInstallerResponse {
-        readonly kind: EventInitializationFailed;
-        readonly message: string;
-    }
-    interface ProjectResponse extends TypingInstallerResponse {
-        readonly projectName: string;
-    }
-    interface SetTypings extends ProjectResponse {
-        readonly typeAcquisition: TypeAcquisition;
-        readonly compilerOptions: CompilerOptions;
-        readonly typings: string[];
-        readonly unresolvedImports: SortedReadonlyArray<string>;
-        readonly kind: ActionSet;
-    }
-    interface InvalidateCachedTypings extends ProjectResponse {
-        readonly kind: ActionInvalidate;
-    }
-    interface InstallTypes extends ProjectResponse {
-        readonly kind: EventBeginInstallTypes | EventEndInstallTypes;
-        readonly eventId: number;
-        readonly typingsInstallerVersion: string;
-        readonly packagesToInstall: ReadonlyArray<string>;
-    }
-    interface BeginInstallTypes extends InstallTypes {
-        readonly kind: EventBeginInstallTypes;
-    }
-    interface EndInstallTypes extends InstallTypes {
-        readonly kind: EventEndInstallTypes;
-        readonly installSuccess: boolean;
-    }
-}
-declare namespace ts.server {
-    const ActionSet: ActionSet;
-    const ActionInvalidate: ActionInvalidate;
-    const ActionPackageInstalled: ActionPackageInstalled;
-    const EventTypesRegistry: EventTypesRegistry;
-    const EventBeginInstallTypes: EventBeginInstallTypes;
-    const EventEndInstallTypes: EventEndInstallTypes;
-    const EventInitializationFailed: EventInitializationFailed;
-    namespace Arguments {
-        const GlobalCacheLocation = "--globalTypingsCacheLocation";
-        const LogFile = "--logFile";
-        const EnableTelemetry = "--enableTelemetry";
-        const TypingSafeListLocation = "--typingSafeListLocation";
-        const TypesMapLocation = "--typesMapLocation";
-        /**
-         * This argument specifies the location of the NPM executable.
-         * typingsInstaller will run the command with `${npmLocation} install ...`.
-         */
-        const NpmLocation = "--npmLocation";
-    }
-    function hasArgument(argumentName: string): boolean;
-    function findArgument(argumentName: string): string | undefined;
 }
 declare namespace ts.server {
     enum LogLevel {
@@ -5494,7 +12077,6 @@ declare namespace ts.server {
         Perf = "Perf"
     }
     namespace Msg {
-        /** @deprecated Only here for backwards-compatibility. Prefer just `Msg`. */
         type Types = Msg;
     }
     function createInstallTypingsRequest(project: Project, typeAcquisition: TypeAcquisition, unresolvedImports: SortedReadonlyArray<string>, cachePath?: string): DiscoverTypings;
@@ -5519,16 +12101,10 @@ declare namespace ts.server {
     function createNormalizedPathMap<T>(): NormalizedPathMap<T>;
     interface ProjectOptions {
         configHasExtendsProperty: boolean;
-        /**
-         * true if config file explicitly listed files
-         */
         configHasFilesProperty: boolean;
         configHasIncludeProperty: boolean;
         configHasExcludeProperty: boolean;
         projectReferences: ReadonlyArray<ProjectReference> | undefined;
-        /**
-         * these fields can be present in the project file
-         */
         files?: string[];
         wildcardDirectories?: Map<WatchDirectoryFlags>;
         compilerOptions?: CompilerOptions;
@@ -5539,47 +12115,86 @@ declare namespace ts.server {
     function makeInferredProjectName(counter: number): string;
     function createSortedArray<T>(): SortedArray<T>;
 }
-/**
- * Declaration module describing the TypeScript Server protocol
- */
+declare namespace ts.server {
+    class ThrottledOperations {
+        private readonly host;
+        private readonly pendingTimeouts;
+        private readonly logger?;
+        constructor(host: ServerHost, logger: Logger);
+        schedule(operationId: string, delay: number, cb: () => void): void;
+        private static run;
+    }
+    class GcTimer {
+        private readonly host;
+        private readonly delay;
+        private readonly logger;
+        private timerId;
+        constructor(host: ServerHost, delay: number, logger: Logger);
+        scheduleCollect(): void;
+        private static run;
+    }
+    function getBaseConfigFileName(configFilePath: NormalizedPath): "tsconfig.json" | "jsconfig.json" | undefined;
+    function removeSorted<T>(array: SortedArray<T>, remove: T, compare: Comparer<T>): void;
+    function toSortedArray(arr: string[]): SortedArray<string>;
+    function toSortedArray<T>(arr: T[], comparer: Comparer<T>): SortedArray<T>;
+    function toDeduplicatedSortedArray(arr: string[]): SortedArray<string>;
+    function indent(str: string): string;
+    function stringifyIndented(json: {}): string;
+}
 declare namespace ts.server.protocol {
     enum CommandTypes {
         JsxClosingTag = "jsxClosingTag",
         Brace = "brace",
+        BraceFull = "brace-full",
         BraceCompletion = "braceCompletion",
         GetSpanOfEnclosingComment = "getSpanOfEnclosingComment",
         Change = "change",
         Close = "close",
         Completions = "completions",
+        CompletionsFull = "completions-full",
         CompletionDetails = "completionEntryDetails",
+        CompletionDetailsFull = "completionEntryDetails-full",
         CompileOnSaveAffectedFileList = "compileOnSaveAffectedFileList",
         CompileOnSaveEmitFile = "compileOnSaveEmitFile",
         Configure = "configure",
         Definition = "definition",
+        DefinitionFull = "definition-full",
         DefinitionAndBoundSpan = "definitionAndBoundSpan",
+        DefinitionAndBoundSpanFull = "definitionAndBoundSpan-full",
         Implementation = "implementation",
+        ImplementationFull = "implementation-full",
         Exit = "exit",
         Format = "format",
         Formatonkey = "formatonkey",
+        FormatFull = "format-full",
+        FormatonkeyFull = "formatonkey-full",
+        FormatRangeFull = "formatRange-full",
         Geterr = "geterr",
         GeterrForProject = "geterrForProject",
         SemanticDiagnosticsSync = "semanticDiagnosticsSync",
         SyntacticDiagnosticsSync = "syntacticDiagnosticsSync",
         SuggestionDiagnosticsSync = "suggestionDiagnosticsSync",
         NavBar = "navbar",
+        NavBarFull = "navbar-full",
         Navto = "navto",
+        NavtoFull = "navto-full",
         NavTree = "navtree",
         NavTreeFull = "navtree-full",
-        /** @deprecated */
         Occurrences = "occurrences",
         DocumentHighlights = "documentHighlights",
+        DocumentHighlightsFull = "documentHighlights-full",
         Open = "open",
         Quickinfo = "quickinfo",
+        QuickinfoFull = "quickinfo-full",
         References = "references",
+        ReferencesFull = "references-full",
         Reload = "reload",
         Rename = "rename",
+        RenameInfoFull = "rename-full",
+        RenameLocationsFull = "renameLocations-full",
         Saveto = "saveto",
         SignatureHelp = "signatureHelp",
+        SignatureHelpFull = "signatureHelp-full",
         Status = "status",
         TypeDefinition = "typeDefinition",
         ProjectInfo = "projectInfo",
@@ -5588,101 +12203,59 @@ declare namespace ts.server.protocol {
         OpenExternalProject = "openExternalProject",
         OpenExternalProjects = "openExternalProjects",
         CloseExternalProject = "closeExternalProject",
+        SynchronizeProjectList = "synchronizeProjectList",
+        ApplyChangedToOpenFiles = "applyChangedToOpenFiles",
+        EncodedSemanticClassificationsFull = "encodedSemanticClassifications-full",
+        Cleanup = "cleanup",
         GetOutliningSpans = "getOutliningSpans",
+        GetOutliningSpansFull = "outliningSpans",
         TodoComments = "todoComments",
         Indentation = "indentation",
         DocCommentTemplate = "docCommentTemplate",
+        CompilerOptionsDiagnosticsFull = "compilerOptionsDiagnostics-full",
+        NameOrDottedNameSpan = "nameOrDottedNameSpan",
+        BreakpointStatement = "breakpointStatement",
         CompilerOptionsForInferredProjects = "compilerOptionsForInferredProjects",
         GetCodeFixes = "getCodeFixes",
+        GetCodeFixesFull = "getCodeFixes-full",
         GetCombinedCodeFix = "getCombinedCodeFix",
+        GetCombinedCodeFixFull = "getCombinedCodeFix-full",
         ApplyCodeActionCommand = "applyCodeActionCommand",
         GetSupportedCodeFixes = "getSupportedCodeFixes",
         GetApplicableRefactors = "getApplicableRefactors",
         GetEditsForRefactor = "getEditsForRefactor",
+        GetEditsForRefactorFull = "getEditsForRefactor-full",
         OrganizeImports = "organizeImports",
-        GetEditsForFileRename = "getEditsForFileRename"
+        OrganizeImportsFull = "organizeImports-full",
+        GetEditsForFileRename = "getEditsForFileRename",
+        GetEditsForFileRenameFull = "getEditsForFileRename-full"
     }
-    /**
-     * A TypeScript Server message
-     */
     interface Message {
-        /**
-         * Sequence number of the message
-         */
         seq: number;
-        /**
-         * One of "request", "response", or "event"
-         */
         type: "request" | "response" | "event";
     }
-    /**
-     * Client-initiated request message
-     */
     interface Request extends Message {
         type: "request";
-        /**
-         * The command to execute
-         */
         command: string;
-        /**
-         * Object containing arguments for the command
-         */
         arguments?: any;
     }
-    /**
-     * Request to reload the project structure for all the opened files
-     */
     interface ReloadProjectsRequest extends Message {
         command: CommandTypes.ReloadProjects;
     }
-    /**
-     * Server-initiated event message
-     */
     interface Event extends Message {
         type: "event";
-        /**
-         * Name of event
-         */
         event: string;
-        /**
-         * Event-specific information
-         */
         body?: any;
     }
-    /**
-     * Response by server to client request message.
-     */
     interface Response extends Message {
         type: "response";
-        /**
-         * Sequence number of the request message.
-         */
         request_seq: number;
-        /**
-         * Outcome of the request.
-         */
         success: boolean;
-        /**
-         * The command requested.
-         */
         command: string;
-        /**
-         * If success === false, this should always be provided.
-         * Otherwise, may (or may not) contain a success message.
-         */
         message?: string;
-        /**
-         * Contains message body if success === true.
-         */
         body?: any;
     }
-    /**
-     * Arguments for FileRequest messages.
-     */
     interface FileRequestArgs {
-        /**
-         * The file for the request (absolute pathname required).
-         */
         file: string;
         projectFileName?: string;
     }
@@ -5690,183 +12263,85 @@ declare namespace ts.server.protocol {
         command: CommandTypes.Status;
     }
     interface StatusResponseBody {
-        /**
-         * The TypeScript version (`ts.version`).
-         */
         version: string;
     }
-    /**
-     * Response to StatusRequest
-     */
     interface StatusResponse extends Response {
         body: StatusResponseBody;
     }
-    /**
-     * Requests a JS Doc comment template for a given position
-     */
     interface DocCommentTemplateRequest extends FileLocationRequest {
         command: CommandTypes.DocCommentTemplate;
     }
-    /**
-     * Response to DocCommentTemplateRequest
-     */
     interface DocCommandTemplateResponse extends Response {
         body?: TextInsertion;
     }
-    /**
-     * A request to get TODO comments from the file
-     */
     interface TodoCommentRequest extends FileRequest {
         command: CommandTypes.TodoComments;
         arguments: TodoCommentRequestArgs;
     }
-    /**
-     * Arguments for TodoCommentRequest request.
-     */
     interface TodoCommentRequestArgs extends FileRequestArgs {
-        /**
-         * Array of target TodoCommentDescriptors that describes TODO comments to be found
-         */
         descriptors: TodoCommentDescriptor[];
     }
-    /**
-     * Response for TodoCommentRequest request.
-     */
     interface TodoCommentsResponse extends Response {
         body?: TodoComment[];
     }
-    /**
-     * A request to determine if the caret is inside a comment.
-     */
     interface SpanOfEnclosingCommentRequest extends FileLocationRequest {
         command: CommandTypes.GetSpanOfEnclosingComment;
         arguments: SpanOfEnclosingCommentRequestArgs;
     }
     interface SpanOfEnclosingCommentRequestArgs extends FileLocationRequestArgs {
-        /**
-         * Requires that the enclosing span be a multi-line comment, or else the request returns undefined.
-         */
         onlyMultiLine: boolean;
     }
-    /**
-     * Request to obtain outlining spans in file.
-     */
     interface OutliningSpansRequest extends FileRequest {
         command: CommandTypes.GetOutliningSpans;
     }
     interface OutliningSpan {
-        /** The span of the document to actually collapse. */
         textSpan: TextSpan;
-        /** The span of the document to display when the user hovers over the collapsed span. */
         hintSpan: TextSpan;
-        /** The text to display in the editor for the collapsed region. */
         bannerText: string;
-        /**
-         * Whether or not this region should be automatically collapsed when
-         * the 'Collapse to Definitions' command is invoked.
-         */
         autoCollapse: boolean;
-        /**
-         * Classification of the contents of the span
-         */
         kind: OutliningSpanKind;
     }
-    /**
-     * Response to OutliningSpansRequest request.
-     */
     interface OutliningSpansResponse extends Response {
         body?: OutliningSpan[];
     }
-    /**
-     * A request to get indentation for a location in file
-     */
+    interface OutliningSpansRequestFull extends FileRequest {
+        command: CommandTypes.GetOutliningSpansFull;
+    }
+    interface OutliningSpansResponseFull extends Response {
+        body?: ts.OutliningSpan[];
+    }
     interface IndentationRequest extends FileLocationRequest {
         command: CommandTypes.Indentation;
         arguments: IndentationRequestArgs;
     }
-    /**
-     * Response for IndentationRequest request.
-     */
     interface IndentationResponse extends Response {
         body?: IndentationResult;
     }
-    /**
-     * Indentation result representing where indentation should be placed
-     */
     interface IndentationResult {
-        /**
-         * The base position in the document that the indent should be relative to
-         */
         position: number;
-        /**
-         * The number of columns the indent should be at relative to the position's column.
-         */
         indentation: number;
     }
-    /**
-     * Arguments for IndentationRequest request.
-     */
     interface IndentationRequestArgs extends FileLocationRequestArgs {
-        /**
-         * An optional set of settings to be used when computing indentation.
-         * If argument is omitted - then it will use settings for file that were previously set via 'configure' request or global settings.
-         */
         options?: EditorSettings;
     }
-    /**
-     * Arguments for ProjectInfoRequest request.
-     */
     interface ProjectInfoRequestArgs extends FileRequestArgs {
-        /**
-         * Indicate if the file name list of the project is needed
-         */
         needFileNameList: boolean;
     }
-    /**
-     * A request to get the project information of the current file.
-     */
     interface ProjectInfoRequest extends Request {
         command: CommandTypes.ProjectInfo;
         arguments: ProjectInfoRequestArgs;
     }
-    /**
-     * A request to retrieve compiler options diagnostics for a project
-     */
     interface CompilerOptionsDiagnosticsRequest extends Request {
         arguments: CompilerOptionsDiagnosticsRequestArgs;
     }
-    /**
-     * Arguments for CompilerOptionsDiagnosticsRequest request.
-     */
     interface CompilerOptionsDiagnosticsRequestArgs {
-        /**
-         * Name of the project to retrieve compiler options diagnostics.
-         */
         projectFileName: string;
     }
-    /**
-     * Response message body for "projectInfo" request
-     */
     interface ProjectInfo {
-        /**
-         * For configured project, this is the normalized path of the 'tsconfig.json' file
-         * For inferred project, this is undefined
-         */
         configFileName: string;
-        /**
-         * The list of normalized file name in the project, including 'lib.d.ts'
-         */
         fileNames?: string[];
-        /**
-         * Indicates if the project has a active language service instance
-         */
         languageServiceDisabled?: boolean;
     }
-    /**
-     * Represents diagnostic info that includes location of diagnostic in two forms
-     * - start position and length of the error span
-     * - startLocation and endLocation - a pair of Location objects that store start/end line and offset of the error span.
-     */
     interface DiagnosticWithLinePosition {
         message: string;
         start: number;
@@ -5875,98 +12350,42 @@ declare namespace ts.server.protocol {
         endLocation: Location;
         category: string;
         code: number;
-        /** May store more in future. For now, this will simply be `true` to indicate when a diagnostic is an unused-identifier diagnostic. */
         reportsUnnecessary?: {};
     }
-    /**
-     * Response message for "projectInfo" request
-     */
     interface ProjectInfoResponse extends Response {
         body?: ProjectInfo;
     }
-    /**
-     * Request whose sole parameter is a file name.
-     */
     interface FileRequest extends Request {
         arguments: FileRequestArgs;
     }
-    /**
-     * Instances of this interface specify a location in a source file:
-     * (file, line, character offset), where line and character offset are 1-based.
-     */
     interface FileLocationRequestArgs extends FileRequestArgs {
-        /**
-         * The line number for the request (1-based).
-         */
         line: number;
-        /**
-         * The character offset (on the line) for the request (1-based).
-         */
         offset: number;
+        position?: number;
     }
     type FileLocationOrRangeRequestArgs = FileLocationRequestArgs | FileRangeRequestArgs;
-    /**
-     * Request refactorings at a given position or selection area.
-     */
     interface GetApplicableRefactorsRequest extends Request {
         command: CommandTypes.GetApplicableRefactors;
         arguments: GetApplicableRefactorsRequestArgs;
     }
     type GetApplicableRefactorsRequestArgs = FileLocationOrRangeRequestArgs;
-    /**
-     * Response is a list of available refactorings.
-     * Each refactoring exposes one or more "Actions"; a user selects one action to invoke a refactoring
-     */
     interface GetApplicableRefactorsResponse extends Response {
         body?: ApplicableRefactorInfo[];
     }
-    /**
-     * A set of one or more available refactoring actions, grouped under a parent refactoring.
-     */
     interface ApplicableRefactorInfo {
-        /**
-         * The programmatic name of the refactoring
-         */
         name: string;
-        /**
-         * A description of this refactoring category to show to the user.
-         * If the refactoring gets inlined (see below), this text will not be visible.
-         */
         description: string;
-        /**
-         * Inlineable refactorings can have their actions hoisted out to the top level
-         * of a context menu. Non-inlineanable refactorings should always be shown inside
-         * their parent grouping.
-         *
-         * If not specified, this value is assumed to be 'true'
-         */
         inlineable?: boolean;
         actions: RefactorActionInfo[];
     }
-    /**
-     * Represents a single refactoring action - for example, the "Extract Method..." refactor might
-     * offer several actions, each corresponding to a surround class or closure to extract into.
-     */
     interface RefactorActionInfo {
-        /**
-         * The programmatic name of the refactoring action
-         */
         name: string;
-        /**
-         * A description of this refactoring action to show to the user.
-         * If the parent refactoring is inlined away, this will be the only text shown,
-         * so this description should make sense by itself if the parent is inlineable=true
-         */
         description: string;
     }
     interface GetEditsForRefactorRequest extends Request {
         command: CommandTypes.GetEditsForRefactor;
         arguments: GetEditsForRefactorRequestArgs;
     }
-    /**
-     * Request the edits that a particular refactoring action produces.
-     * Callers must specify the name of the refactor and the name of the action.
-     */
     type GetEditsForRefactorRequestArgs = FileLocationOrRangeRequestArgs & {
         refactor: string;
         action: string;
@@ -5976,19 +12395,9 @@ declare namespace ts.server.protocol {
     }
     interface RefactorEditInfo {
         edits: FileCodeEdits[];
-        /**
-         * An optional location where the editor should start a rename operation once
-         * the refactoring edits have been applied
-         */
         renameLocation?: Location;
         renameFilename?: string;
     }
-    /**
-     * Organize imports by:
-     *   1) Removing unused imports
-     *   2) Coalescing imports from the same module
-     *   3) Sorting imports
-     */
     interface OrganizeImportsRequest extends Request {
         command: CommandTypes.OrganizeImports;
         arguments: OrganizeImportsRequestArgs;
@@ -6011,9 +12420,6 @@ declare namespace ts.server.protocol {
     interface GetEditsForFileRenameResponse extends Response {
         edits: ReadonlyArray<FileCodeEdits>;
     }
-    /**
-     * Request for the available codefixes at a specific position.
-     */
     interface CodeFixRequest extends Request {
         command: CommandTypes.GetCodeFixes;
         arguments: CodeFixRequestArgs;
@@ -6032,30 +12438,14 @@ declare namespace ts.server.protocol {
     interface ApplyCodeActionCommandResponse extends Response {
     }
     interface FileRangeRequestArgs extends FileRequestArgs {
-        /**
-         * The line number for the request (1-based).
-         */
         startLine: number;
-        /**
-         * The character offset (on the line) for the request (1-based).
-         */
         startOffset: number;
-        /**
-         * The line number for the request (1-based).
-         */
+        startPosition?: number;
         endLine: number;
-        /**
-         * The character offset (on the line) for the request (1-based).
-         */
         endOffset: number;
+        endPosition?: number;
     }
-    /**
-     * Instances of this interface specify errorcodes on a specific location in a sourcefile.
-     */
     interface CodeFixRequestArgs extends FileRangeRequestArgs {
-        /**
-         * Errorcodes we want to get the fixes for.
-         */
         errorCodes?: ReadonlyArray<number>;
     }
     interface GetCombinedCodeFixRequestArgs {
@@ -6067,151 +12457,71 @@ declare namespace ts.server.protocol {
         args: FileRequestArgs;
     }
     interface ApplyCodeActionCommandRequestArgs {
-        /** May also be an array of commands. */
         command: {};
     }
-    /**
-     * Response for GetCodeFixes request.
-     */
     interface GetCodeFixesResponse extends Response {
         body?: CodeAction[];
     }
-    /**
-     * A request whose arguments specify a file location (file, line, col).
-     */
     interface FileLocationRequest extends FileRequest {
         arguments: FileLocationRequestArgs;
     }
-    /**
-     * A request to get codes of supported code fixes.
-     */
     interface GetSupportedCodeFixesRequest extends Request {
         command: CommandTypes.GetSupportedCodeFixes;
     }
-    /**
-     * A response for GetSupportedCodeFixesRequest request.
-     */
     interface GetSupportedCodeFixesResponse extends Response {
-        /**
-         * List of error codes supported by the server.
-         */
         body?: string[];
     }
-    /**
-     * Arguments for EncodedSemanticClassificationsRequest request.
-     */
+    interface EncodedSemanticClassificationsRequest extends FileRequest {
+        arguments: EncodedSemanticClassificationsRequestArgs;
+    }
     interface EncodedSemanticClassificationsRequestArgs extends FileRequestArgs {
-        /**
-         * Start position of the span.
-         */
         start: number;
-        /**
-         * Length of the span.
-         */
         length: number;
     }
-    /**
-     * Arguments in document highlight request; include: filesToSearch, file,
-     * line, offset.
-     */
     interface DocumentHighlightsRequestArgs extends FileLocationRequestArgs {
-        /**
-         * List of files to search for document highlights.
-         */
         filesToSearch: string[];
     }
-    /**
-     * Go to definition request; value of command field is
-     * "definition". Return response giving the file locations that
-     * define the symbol found in file at location line, col.
-     */
     interface DefinitionRequest extends FileLocationRequest {
         command: CommandTypes.Definition;
     }
-    /**
-     * Go to type request; value of command field is
-     * "typeDefinition". Return response giving the file locations that
-     * define the type for the symbol found in file at location line, col.
-     */
     interface TypeDefinitionRequest extends FileLocationRequest {
         command: CommandTypes.TypeDefinition;
     }
-    /**
-     * Go to implementation request; value of command field is
-     * "implementation". Return response giving the file locations that
-     * implement the symbol found in file at location line, col.
-     */
     interface ImplementationRequest extends FileLocationRequest {
         command: CommandTypes.Implementation;
     }
-    /**
-     * Location in source code expressed as (one-based) line and (one-based) column offset.
-     */
     interface Location {
         line: number;
         offset: number;
     }
-    /**
-     * Object found in response messages defining a span of text in source code.
-     */
     interface TextSpan {
-        /**
-         * First character of the definition.
-         */
         start: Location;
-        /**
-         * One character past last character of the definition.
-         */
         end: Location;
     }
-    /**
-     * Object found in response messages defining a span of text in a specific source file.
-     */
     interface FileSpan extends TextSpan {
-        /**
-         * File containing text span.
-         */
         file: string;
     }
     interface DefinitionInfoAndBoundSpan {
         definitions: ReadonlyArray<FileSpan>;
         textSpan: TextSpan;
     }
-    /**
-     * Definition response message.  Gives text range for definition.
-     */
     interface DefinitionResponse extends Response {
         body?: FileSpan[];
     }
     interface DefinitionInfoAndBoundSpanReponse extends Response {
         body?: DefinitionInfoAndBoundSpan;
     }
-    /**
-     * Definition response message.  Gives text range for definition.
-     */
     interface TypeDefinitionResponse extends Response {
         body?: FileSpan[];
     }
-    /**
-     * Implementation response message.  Gives text range for implementations.
-     */
     interface ImplementationResponse extends Response {
         body?: FileSpan[];
     }
-    /**
-     * Request to get brace completion for a location in the file.
-     */
     interface BraceCompletionRequest extends FileLocationRequest {
         command: CommandTypes.BraceCompletion;
         arguments: BraceCompletionRequestArgs;
     }
-    /**
-     * Argument for BraceCompletionRequest request.
-     */
     interface BraceCompletionRequestArgs extends FileLocationRequestArgs {
-        /**
-         * Kind of opening brace
-         */
         openingBrace: string;
     }
     interface JsxClosingTagRequest extends FileLocationRequest {
@@ -6223,596 +12533,240 @@ declare namespace ts.server.protocol {
     interface JsxClosingTagResponse extends Response {
         readonly body: TextInsertion;
     }
-    /**
-     * @deprecated
-     * Get occurrences request; value of command field is
-     * "occurrences". Return response giving spans that are relevant
-     * in the file at a given line and column.
-     */
     interface OccurrencesRequest extends FileLocationRequest {
         command: CommandTypes.Occurrences;
     }
-    /** @deprecated */
     interface OccurrencesResponseItem extends FileSpan {
-        /**
-         * True if the occurrence is a write location, false otherwise.
-         */
         isWriteAccess: boolean;
-        /**
-         * True if the occurrence is in a string, undefined otherwise;
-         */
         isInString?: true;
     }
-    /** @deprecated */
     interface OccurrencesResponse extends Response {
         body?: OccurrencesResponseItem[];
     }
-    /**
-     * Get document highlights request; value of command field is
-     * "documentHighlights". Return response giving spans that are relevant
-     * in the file at a given line and column.
-     */
     interface DocumentHighlightsRequest extends FileLocationRequest {
         command: CommandTypes.DocumentHighlights;
         arguments: DocumentHighlightsRequestArgs;
     }
-    /**
-     * Span augmented with extra information that denotes the kind of the highlighting to be used for span.
-     */
     interface HighlightSpan extends TextSpan {
         kind: HighlightSpanKind;
     }
-    /**
-     * Represents a set of highligh spans for a give name
-     */
     interface DocumentHighlightsItem {
-        /**
-         * File containing highlight spans.
-         */
         file: string;
-        /**
-         * Spans to highlight in file.
-         */
         highlightSpans: HighlightSpan[];
     }
-    /**
-     * Response for a DocumentHighlightsRequest request.
-     */
     interface DocumentHighlightsResponse extends Response {
         body?: DocumentHighlightsItem[];
     }
-    /**
-     * Find references request; value of command field is
-     * "references". Return response giving the file locations that
-     * reference the symbol found in file at location line, col.
-     */
     interface ReferencesRequest extends FileLocationRequest {
         command: CommandTypes.References;
     }
     interface ReferencesResponseItem extends FileSpan {
-        /** Text of line containing the reference.  Including this
-         *  with the response avoids latency of editor loading files
-         * to show text of reference line (the server already has
-         * loaded the referencing files).
-         */
         lineText: string;
-        /**
-         * True if reference is a write location, false otherwise.
-         */
         isWriteAccess: boolean;
-        /**
-         * True if reference is a definition, false otherwise.
-         */
         isDefinition: boolean;
     }
-    /**
-     * The body of a "references" response message.
-     */
     interface ReferencesResponseBody {
-        /**
-         * The file locations referencing the symbol.
-         */
         refs: ReferencesResponseItem[];
-        /**
-         * The name of the symbol.
-         */
         symbolName: string;
-        /**
-         * The start character offset of the symbol (on the line provided by the references request).
-         */
         symbolStartOffset: number;
-        /**
-         * The full display name of the symbol.
-         */
         symbolDisplayString: string;
     }
-    /**
-     * Response to "references" request.
-     */
     interface ReferencesResponse extends Response {
         body?: ReferencesResponseBody;
     }
-    /**
-     * Argument for RenameRequest request.
-     */
     interface RenameRequestArgs extends FileLocationRequestArgs {
-        /**
-         * Should text at specified location be found/changed in comments?
-         */
         findInComments?: boolean;
-        /**
-         * Should text at specified location be found/changed in strings?
-         */
         findInStrings?: boolean;
     }
-    /**
-     * Rename request; value of command field is "rename". Return
-     * response giving the file locations that reference the symbol
-     * found in file at location line, col. Also return full display
-     * name of the symbol so that client can print it unambiguously.
-     */
     interface RenameRequest extends FileLocationRequest {
         command: CommandTypes.Rename;
         arguments: RenameRequestArgs;
     }
-    /**
-     * Information about the item to be renamed.
-     */
     interface RenameInfo {
-        /**
-         * True if item can be renamed.
-         */
         canRename: boolean;
-        /**
-         * Error message if item can not be renamed.
-         */
         localizedErrorMessage?: string;
-        /**
-         * Display name of the item to be renamed.
-         */
         displayName: string;
-        /**
-         * Full display name of item to be renamed.
-         */
         fullDisplayName: string;
-        /**
-         * The items's kind (such as 'className' or 'parameterName' or plain 'text').
-         */
         kind: ScriptElementKind;
-        /**
-         * Optional modifiers for the kind (such as 'public').
-         */
         kindModifiers: string;
     }
-    /**
-     *  A group of text spans, all in 'file'.
-     */
     interface SpanGroup {
-        /** The file to which the spans apply */
         file: string;
-        /** The text spans in this group */
         locs: TextSpan[];
     }
     interface RenameResponseBody {
-        /**
-         * Information about the item to be renamed.
-         */
         info: RenameInfo;
-        /**
-         * An array of span groups (one per file) that refer to the item to be renamed.
-         */
         locs: ReadonlyArray<SpanGroup>;
     }
-    /**
-     * Rename response message.
-     */
     interface RenameResponse extends Response {
         body?: RenameResponseBody;
     }
-    /**
-     * Represents a file in external project.
-     * External project is project whose set of files, compilation options and open\close state
-     * is maintained by the client (i.e. if all this data come from .csproj file in Visual Studio).
-     * External project will exist even if all files in it are closed and should be closed explicitly.
-     * If external project includes one or more tsconfig.json/jsconfig.json files then tsserver will
-     * create configured project for every config file but will maintain a link that these projects were created
-     * as a result of opening external project so they should be removed once external project is closed.
-     */
     interface ExternalFile {
-        /**
-         * Name of file file
-         */
         fileName: string;
-        /**
-         * Script kind of the file
-         */
         scriptKind?: ScriptKindName | ts.ScriptKind;
-        /**
-         * Whether file has mixed content (i.e. .cshtml file that combines html markup with C#/JavaScript)
-         */
         hasMixedContent?: boolean;
-        /**
-         * Content of the file
-         */
         content?: string;
     }
-    /**
-     * Represent an external project
-     */
     interface ExternalProject {
-        /**
-         * Project name
-         */
         projectFileName: string;
-        /**
-         * List of root files in project
-         */
         rootFiles: ExternalFile[];
-        /**
-         * Compiler options for the project
-         */
         options: ExternalProjectCompilerOptions;
-        /**
-         * @deprecated typingOptions. Use typeAcquisition instead
-         */
         typingOptions?: TypeAcquisition;
-        /**
-         * Explicitly specified type acquisition for the project
-         */
         typeAcquisition?: TypeAcquisition;
     }
     interface CompileOnSaveMixin {
-        /**
-         * If compile on save is enabled for the project
-         */
         compileOnSave?: boolean;
     }
-    /**
-     * For external projects, some of the project settings are sent together with
-     * compiler settings.
-     */
     type ExternalProjectCompilerOptions = CompilerOptions & CompileOnSaveMixin;
-    /**
-     * Represents a set of changes that happen in project
-     */
+    interface ProjectVersionInfo {
+        projectName: string;
+        isInferred: boolean;
+        version: number;
+        options: ts.CompilerOptions;
+        languageServiceDisabled: boolean;
+        lastFileExceededProgramSize?: string;
+    }
     interface ProjectChanges {
-        /**
-         * List of added files
-         */
         added: string[];
-        /**
-         * List of removed files
-         */
         removed: string[];
-        /**
-         * List of updated files
-         */
         updated: string[];
     }
-    /**
-     * Information found in a configure request.
-     */
+    interface ProjectFiles {
+        info?: ProjectVersionInfo;
+        files?: string[];
+        changes?: ProjectChanges;
+    }
+    interface ProjectFilesWithDiagnostics extends ProjectFiles {
+        projectErrors: DiagnosticWithLinePosition[];
+    }
+    interface ChangedOpenFile {
+        fileName: string;
+        changes: ts.TextChange[];
+    }
     interface ConfigureRequestArguments {
-        /**
-         * Information about the host, for example 'Emacs 24.4' or
-         * 'Sublime Text version 3075'
-         */
         hostInfo?: string;
-        /**
-         * If present, tab settings apply only to this file.
-         */
         file?: string;
-        /**
-         * The format options to use during formatting and other code editing features.
-         */
         formatOptions?: FormatCodeSettings;
         preferences?: UserPreferences;
-        /**
-         * The host's additional supported .js file extensions
-         */
         extraFileExtensions?: FileExtensionInfo[];
     }
-    /**
-     *  Configure request; value of command field is "configure".  Specifies
-     *  host information, such as host type, tab size, and indent size.
-     */
     interface ConfigureRequest extends Request {
         command: CommandTypes.Configure;
         arguments: ConfigureRequestArguments;
     }
-    /**
-     * Response to "configure" request.  This is just an acknowledgement, so
-     * no body field is required.
-     */
     interface ConfigureResponse extends Response {
     }
-    /**
-     *  Information found in an "open" request.
-     */
     interface OpenRequestArgs extends FileRequestArgs {
-        /**
-         * Used when a version of the file content is known to be more up to date than the one on disk.
-         * Then the known content will be used upon opening instead of the disk copy
-         */
         fileContent?: string;
-        /**
-         * Used to specify the script kind of the file explicitly. It could be one of the following:
-         *      "TS", "JS", "TSX", "JSX"
-         */
         scriptKindName?: ScriptKindName;
-        /**
-         * Used to limit the searching for project config file. If given the searching will stop at this
-         * root path; otherwise it will go all the way up to the dist root path.
-         */
         projectRootPath?: string;
     }
     type ScriptKindName = "TS" | "JS" | "TSX" | "JSX";
-    /**
-     * Open request; value of command field is "open". Notify the
-     * server that the client has file open.  The server will not
-     * monitor the filesystem for changes in this file and will assume
-     * that the client is updating the server (using the change and/or
-     * reload messages) when the file changes. Server does not currently
-     * send a response to an open request.
-     */
     interface OpenRequest extends Request {
         command: CommandTypes.Open;
         arguments: OpenRequestArgs;
     }
-    /**
-     * Request to open or update external project
-     */
     interface OpenExternalProjectRequest extends Request {
         command: CommandTypes.OpenExternalProject;
         arguments: OpenExternalProjectArgs;
     }
-    /**
-     * Arguments to OpenExternalProjectRequest request
-     */
     type OpenExternalProjectArgs = ExternalProject;
-    /**
-     * Request to open multiple external projects
-     */
     interface OpenExternalProjectsRequest extends Request {
         command: CommandTypes.OpenExternalProjects;
         arguments: OpenExternalProjectsArgs;
     }
-    /**
-     * Arguments to OpenExternalProjectsRequest
-     */
     interface OpenExternalProjectsArgs {
-        /**
-         * List of external projects to open or update
-         */
         projects: ExternalProject[];
     }
-    /**
-     * Response to OpenExternalProjectRequest request. This is just an acknowledgement, so
-     * no body field is required.
-     */
     interface OpenExternalProjectResponse extends Response {
     }
-    /**
-     * Response to OpenExternalProjectsRequest request. This is just an acknowledgement, so
-     * no body field is required.
-     */
     interface OpenExternalProjectsResponse extends Response {
     }
-    /**
-     * Request to close external project.
-     */
     interface CloseExternalProjectRequest extends Request {
         command: CommandTypes.CloseExternalProject;
         arguments: CloseExternalProjectRequestArgs;
     }
-    /**
-     * Arguments to CloseExternalProjectRequest request
-     */
     interface CloseExternalProjectRequestArgs {
-        /**
-         * Name of the project to close
-         */
         projectFileName: string;
     }
-    /**
-     * Response to CloseExternalProjectRequest request. This is just an acknowledgement, so
-     * no body field is required.
-     */
     interface CloseExternalProjectResponse extends Response {
     }
-    /**
-     * Request to set compiler options for inferred projects.
-     * External projects are opened / closed explicitly.
-     * Configured projects are opened when user opens loose file that has 'tsconfig.json' or 'jsconfig.json' anywhere in one of containing folders.
-     * This configuration file will be used to obtain a list of files and configuration settings for the project.
-     * Inferred projects are created when user opens a loose file that is not the part of external project
-     * or configured project and will contain only open file and transitive closure of referenced files if 'useOneInferredProject' is false,
-     * or all open loose files and its transitive closure of referenced files if 'useOneInferredProject' is true.
-     */
+    interface SynchronizeProjectListRequest extends Request {
+        arguments: SynchronizeProjectListRequestArgs;
+    }
+    interface SynchronizeProjectListRequestArgs {
+        knownProjects: protocol.ProjectVersionInfo[];
+    }
+    interface ApplyChangedToOpenFilesRequest extends Request {
+        arguments: ApplyChangedToOpenFilesRequestArgs;
+    }
+    interface ApplyChangedToOpenFilesRequestArgs {
+        openFiles?: ExternalFile[];
+        changedFiles?: ChangedOpenFile[];
+        closedFiles?: string[];
+    }
     interface SetCompilerOptionsForInferredProjectsRequest extends Request {
         command: CommandTypes.CompilerOptionsForInferredProjects;
         arguments: SetCompilerOptionsForInferredProjectsArgs;
     }
-    /**
-     * Argument for SetCompilerOptionsForInferredProjectsRequest request.
-     */
     interface SetCompilerOptionsForInferredProjectsArgs {
-        /**
-         * Compiler options to be used with inferred projects.
-         */
         options: ExternalProjectCompilerOptions;
-        /**
-         * Specifies the project root path used to scope compiler options.
-         * It is an error to provide this property if the server has not been started with
-         * `useInferredProjectPerProjectRoot` enabled.
-         */
         projectRootPath?: string;
     }
-    /**
-     * Response to SetCompilerOptionsForInferredProjectsResponse request. This is just an acknowledgement, so
-     * no body field is required.
-     */
     interface SetCompilerOptionsForInferredProjectsResponse extends Response {
     }
-    /**
-     *  Exit request; value of command field is "exit".  Ask the server process
-     *  to exit.
-     */
     interface ExitRequest extends Request {
         command: CommandTypes.Exit;
     }
-    /**
-     * Close request; value of command field is "close". Notify the
-     * server that the client has closed a previously open file.  If
-     * file is still referenced by open files, the server will resume
-     * monitoring the filesystem for changes to file.  Server does not
-     * currently send a response to a close request.
-     */
     interface CloseRequest extends FileRequest {
         command: CommandTypes.Close;
     }
-    /**
-     * Request to obtain the list of files that should be regenerated if target file is recompiled.
-     * NOTE: this us query-only operation and does not generate any output on disk.
-     */
     interface CompileOnSaveAffectedFileListRequest extends FileRequest {
         command: CommandTypes.CompileOnSaveAffectedFileList;
     }
-    /**
-     * Contains a list of files that should be regenerated in a project
-     */
     interface CompileOnSaveAffectedFileListSingleProject {
-        /**
-         * Project name
-         */
         projectFileName: string;
-        /**
-         * List of files names that should be recompiled
-         */
         fileNames: string[];
-        /**
-         * true if project uses outFile or out compiler option
-         */
         projectUsesOutFile: boolean;
     }
-    /**
-     * Response for CompileOnSaveAffectedFileListRequest request;
-     */
     interface CompileOnSaveAffectedFileListResponse extends Response {
         body: CompileOnSaveAffectedFileListSingleProject[];
     }
-    /**
-     * Request to recompile the file. All generated outputs (.js, .d.ts or .js.map files) is written on disk.
-     */
     interface CompileOnSaveEmitFileRequest extends FileRequest {
         command: CommandTypes.CompileOnSaveEmitFile;
         arguments: CompileOnSaveEmitFileRequestArgs;
     }
-    /**
-     * Arguments for CompileOnSaveEmitFileRequest
-     */
     interface CompileOnSaveEmitFileRequestArgs extends FileRequestArgs {
-        /**
-         * if true - then file should be recompiled even if it does not have any changes.
-         */
         forced?: boolean;
     }
-    /**
-     * Quickinfo request; value of command field is
-     * "quickinfo". Return response giving a quick type and
-     * documentation string for the symbol found in file at location
-     * line, col.
-     */
     interface QuickInfoRequest extends FileLocationRequest {
         command: CommandTypes.Quickinfo;
     }
-    /**
-     * Body of QuickInfoResponse.
-     */
     interface QuickInfoResponseBody {
-        /**
-         * The symbol's kind (such as 'className' or 'parameterName' or plain 'text').
-         */
         kind: ScriptElementKind;
-        /**
-         * Optional modifiers for the kind (such as 'public').
-         */
         kindModifiers: string;
-        /**
-         * Starting file location of symbol.
-         */
         start: Location;
-        /**
-         * One past last character of symbol.
-         */
         end: Location;
-        /**
-         * Type and kind of symbol.
-         */
         displayString: string;
-        /**
-         * Documentation associated with symbol.
-         */
         documentation: string;
-        /**
-         * JSDoc tags associated with symbol.
-         */
         tags: JSDocTagInfo[];
     }
-    /**
-     * Quickinfo response message.
-     */
     interface QuickInfoResponse extends Response {
         body?: QuickInfoResponseBody;
     }
-    /**
-     * Arguments for format messages.
-     */
     interface FormatRequestArgs extends FileLocationRequestArgs {
-        /**
-         * Last line of range for which to format text in file.
-         */
         endLine: number;
-        /**
-         * Character offset on last line of range for which to format text in file.
-         */
         endOffset: number;
-        /**
-         * Format options to be used.
-         */
+        endPosition?: number;
         options?: FormatCodeSettings;
     }
-    /**
-     * Format request; value of command field is "format".  Return
-     * response giving zero or more edit instructions.  The edit
-     * instructions will be sorted in file order.  Applying the edit
-     * instructions in reverse to file will result in correctly
-     * reformatted text.
-     */
     interface FormatRequest extends FileLocationRequest {
         command: CommandTypes.Format;
         arguments: FormatRequestArgs;
     }
-    /**
-     * Object found in response messages defining an editing
-     * instruction for a span of text in source code.  The effect of
-     * this instruction is to replace the text starting at start and
-     * ending one character before end with newText. For an insertion,
-     * the text span is empty.  For a deletion, newText is empty.
-     */
     interface CodeEdit {
-        /**
-         * First character of the text span to edit.
-         */
         start: Location;
-        /**
-         * One character past last character of the text span to edit.
-         */
         end: Location;
-        /**
-         * Replace the span defined above with this string (may be
-         * the empty string).
-         */
         newText: string;
     }
     interface FileCodeEdits {
@@ -6820,15 +12774,11 @@ declare namespace ts.server.protocol {
         textChanges: CodeEdit[];
     }
     interface CodeFixResponse extends Response {
-        /** The code actions that are available */
         body?: CodeFixAction[];
     }
     interface CodeAction {
-        /** Description of the code action to display in the UI of the editor */
         description: string;
-        /** Text changes to apply to each file as part of the code action */
         changes: FileCodeEdits[];
-        /** A command is an opaque object that should be passed to `ApplyCodeActionCommandRequestArgs` without modification.  */
         commands?: {}[];
     }
     interface CombinedCodeActions {
@@ -6836,193 +12786,66 @@ declare namespace ts.server.protocol {
         commands?: ReadonlyArray<{}>;
     }
     interface CodeFixAction extends CodeAction {
-        /** Short name to identify the fix, for use by telemetry. */
         fixName: string;
-        /**
-         * If present, one may call 'getCombinedCodeFix' with this fixId.
-         * This may be omitted to indicate that the code fix can't be applied in a group.
-         */
         fixId?: {};
-        /** Should be present if and only if 'fixId' is. */
         fixAllDescription?: string;
     }
-    /**
-     * Format and format on key response message.
-     */
     interface FormatResponse extends Response {
         body?: CodeEdit[];
     }
-    /**
-     * Arguments for format on key messages.
-     */
     interface FormatOnKeyRequestArgs extends FileLocationRequestArgs {
-        /**
-         * Key pressed (';', '\n', or '}').
-         */
         key: string;
         options?: FormatCodeSettings;
     }
-    /**
-     * Format on key request; value of command field is
-     * "formatonkey". Given file location and key typed (as string),
-     * return response giving zero or more edit instructions.  The
-     * edit instructions will be sorted in file order.  Applying the
-     * edit instructions in reverse to file will result in correctly
-     * reformatted text.
-     */
     interface FormatOnKeyRequest extends FileLocationRequest {
         command: CommandTypes.Formatonkey;
         arguments: FormatOnKeyRequestArgs;
     }
     type CompletionsTriggerCharacter = "." | '"' | "'" | "`" | "/" | "@" | "<";
-    /**
-     * Arguments for completions messages.
-     */
     interface CompletionsRequestArgs extends FileLocationRequestArgs {
-        /**
-         * Optional prefix to apply to possible completions.
-         */
         prefix?: string;
         triggerCharacter?: CompletionsTriggerCharacter;
-        /**
-         * @deprecated Use UserPreferences.includeCompletionsForModuleExports
-         */
         includeExternalModuleExports?: boolean;
-        /**
-         * @deprecated Use UserPreferences.includeCompletionsWithInsertText
-         */
         includeInsertTextCompletions?: boolean;
     }
-    /**
-     * Completions request; value of command field is "completions".
-     * Given a file location (file, line, col) and a prefix (which may
-     * be the empty string), return the possible completions that
-     * begin with prefix.
-     */
     interface CompletionsRequest extends FileLocationRequest {
         command: CommandTypes.Completions;
         arguments: CompletionsRequestArgs;
     }
-    /**
-     * Arguments for completion details request.
-     */
     interface CompletionDetailsRequestArgs extends FileLocationRequestArgs {
-        /**
-         * Names of one or more entries for which to obtain details.
-         */
         entryNames: (string | CompletionEntryIdentifier)[];
     }
     interface CompletionEntryIdentifier {
         name: string;
         source?: string;
     }
-    /**
-     * Completion entry details request; value of command field is
-     * "completionEntryDetails".  Given a file location (file, line,
-     * col) and an array of completion entry names return more
-     * detailed information for each completion entry.
-     */
     interface CompletionDetailsRequest extends FileLocationRequest {
         command: CommandTypes.CompletionDetails;
         arguments: CompletionDetailsRequestArgs;
     }
-    /**
-     * Part of a symbol description.
-     */
     interface SymbolDisplayPart {
-        /**
-         * Text of an item describing the symbol.
-         */
         text: string;
-        /**
-         * The symbol's kind (such as 'className' or 'parameterName' or plain 'text').
-         */
         kind: string;
     }
-    /**
-     * An item found in a completion response.
-     */
     interface CompletionEntry {
-        /**
-         * The symbol's name.
-         */
         name: string;
-        /**
-         * The symbol's kind (such as 'className' or 'parameterName').
-         */
         kind: ScriptElementKind;
-        /**
-         * Optional modifiers for the kind (such as 'public').
-         */
         kindModifiers?: string;
-        /**
-         * A string that is used for comparing completion items so that they can be ordered.  This
-         * is often the same as the name but may be different in certain circumstances.
-         */
         sortText: string;
-        /**
-         * Text to insert instead of `name`.
-         * This is used to support bracketed completions; If `name` might be "a-b" but `insertText` would be `["a-b"]`,
-         * coupled with `replacementSpan` to replace a dotted access with a bracket access.
-         */
         insertText?: string;
-        /**
-         * An optional span that indicates the text to be replaced by this completion item.
-         * If present, this span should be used instead of the default one.
-         * It will be set if the required span differs from the one generated by the default replacement behavior.
-         */
         replacementSpan?: TextSpan;
-        /**
-         * Indicates whether commiting this completion entry will require additional code actions to be
-         * made to avoid errors. The CompletionEntryDetails will have these actions.
-         */
         hasAction?: true;
-        /**
-         * Identifier (not necessarily human-readable) identifying where this completion came from.
-         */
         source?: string;
-        /**
-         * If true, this completion should be highlighted as recommended. There will only be one of these.
-         * This will be set when we know the user should write an expression with a certain type and that type is an enum or constructable class.
-         * Then either that enum/class or a namespace containing it will be the recommended symbol.
-         */
         isRecommended?: true;
     }
-    /**
-     * Additional completion entry details, available on demand
-     */
     interface CompletionEntryDetails {
-        /**
-         * The symbol's name.
-         */
         name: string;
-        /**
-         * The symbol's kind (such as 'className' or 'parameterName').
-         */
         kind: ScriptElementKind;
-        /**
-         * Optional modifiers for the kind (such as 'public').
-         */
         kindModifiers: string;
-        /**
-         * Display parts of the symbol (similar to quick info).
-         */
         displayParts: SymbolDisplayPart[];
-        /**
-         * Documentation strings for the symbol.
-         */
         documentation?: SymbolDisplayPart[];
-        /**
-         * JSDoc tags for the symbol.
-         */
         tags?: JSDocTagInfo[];
-        /**
-         * The associated code actions for this entry
-         */
         codeActions?: CodeAction[];
-        /**
-         * Human-readable description of the `source` from the CompletionEntry.
-         */
         source?: SymbolDisplayPart[];
     }
     interface CompletionsResponse extends Response {
@@ -7031,108 +12854,37 @@ declare namespace ts.server.protocol {
     interface CompletionDetailsResponse extends Response {
         body?: CompletionEntryDetails[];
     }
-    /**
-     * Signature help information for a single parameter
-     */
     interface SignatureHelpParameter {
-        /**
-         * The parameter's name
-         */
         name: string;
-        /**
-         * Documentation of the parameter.
-         */
         documentation: SymbolDisplayPart[];
-        /**
-         * Display parts of the parameter.
-         */
         displayParts: SymbolDisplayPart[];
-        /**
-         * Whether the parameter is optional or not.
-         */
         isOptional: boolean;
     }
-    /**
-     * Represents a single signature to show in signature help.
-     */
     interface SignatureHelpItem {
-        /**
-         * Whether the signature accepts a variable number of arguments.
-         */
         isVariadic: boolean;
-        /**
-         * The prefix display parts.
-         */
         prefixDisplayParts: SymbolDisplayPart[];
-        /**
-         * The suffix display parts.
-         */
         suffixDisplayParts: SymbolDisplayPart[];
-        /**
-         * The separator display parts.
-         */
         separatorDisplayParts: SymbolDisplayPart[];
-        /**
-         * The signature helps items for the parameters.
-         */
         parameters: SignatureHelpParameter[];
-        /**
-         * The signature's documentation
-         */
         documentation: SymbolDisplayPart[];
-        /**
-         * The signature's JSDoc tags
-         */
         tags: JSDocTagInfo[];
     }
-    /**
-     * Signature help items found in the response of a signature help request.
-     */
     interface SignatureHelpItems {
-        /**
-         * The signature help items.
-         */
         items: SignatureHelpItem[];
-        /**
-         * The span for which signature help should appear on a signature
-         */
         applicableSpan: TextSpan;
-        /**
-         * The item selected in the set of available help items.
-         */
         selectedItemIndex: number;
-        /**
-         * The argument selected in the set of parameters.
-         */
         argumentIndex: number;
-        /**
-         * The argument count
-         */
         argumentCount: number;
     }
-    /**
-     * Arguments of a signature help request.
-     */
     interface SignatureHelpRequestArgs extends FileLocationRequestArgs {
     }
-    /**
-     * Signature help request; value of command field is "signatureHelp".
-     * Given a file location (file, line, col), return the signature
-     * help.
-     */
     interface SignatureHelpRequest extends FileLocationRequest {
         command: CommandTypes.SignatureHelp;
         arguments: SignatureHelpRequestArgs;
     }
-    /**
-     * Response object for a SignatureHelpRequest.
-     */
     interface SignatureHelpResponse extends Response {
         body?: SignatureHelpItems;
     }
-    /**
-     * Synchronous request for semantic diagnostics of one file.
-     */
     interface SemanticDiagnosticsSyncRequest extends FileRequest {
         command: CommandTypes.SemanticDiagnosticsSync;
         arguments: SemanticDiagnosticsSyncRequestArgs;
@@ -7140,9 +12892,6 @@ declare namespace ts.server.protocol {
     interface SemanticDiagnosticsSyncRequestArgs extends FileRequestArgs {
         includeLinePosition?: boolean;
     }
-    /**
-     * Response object for synchronous sematic diagnostics request.
-     */
     interface SemanticDiagnosticsSyncResponse extends Response {
         body?: Diagnostic[] | DiagnosticWithLinePosition[];
     }
@@ -7152,9 +12901,6 @@ declare namespace ts.server.protocol {
     }
     type SuggestionDiagnosticsSyncRequestArgs = SemanticDiagnosticsSyncRequestArgs;
     type SuggestionDiagnosticsSyncResponse = SemanticDiagnosticsSyncResponse;
-    /**
-     * Synchronous request for syntactic diagnostics of one file.
-     */
     interface SyntacticDiagnosticsSyncRequest extends FileRequest {
         command: CommandTypes.SyntacticDiagnosticsSync;
         arguments: SyntacticDiagnosticsSyncRequestArgs;
@@ -7162,68 +12908,26 @@ declare namespace ts.server.protocol {
     interface SyntacticDiagnosticsSyncRequestArgs extends FileRequestArgs {
         includeLinePosition?: boolean;
     }
-    /**
-     * Response object for synchronous syntactic diagnostics request.
-     */
     interface SyntacticDiagnosticsSyncResponse extends Response {
         body?: Diagnostic[] | DiagnosticWithLinePosition[];
     }
-    /**
-     * Arguments for GeterrForProject request.
-     */
     interface GeterrForProjectRequestArgs {
-        /**
-         * the file requesting project error list
-         */
         file: string;
-        /**
-         * Delay in milliseconds to wait before starting to compute
-         * errors for the files in the file list
-         */
         delay: number;
     }
-    /**
-     * GeterrForProjectRequest request; value of command field is
-     * "geterrForProject". It works similarly with 'Geterr', only
-     * it request for every file in this project.
-     */
     interface GeterrForProjectRequest extends Request {
         command: CommandTypes.GeterrForProject;
         arguments: GeterrForProjectRequestArgs;
     }
-    /**
-     * Arguments for geterr messages.
-     */
     interface GeterrRequestArgs {
-        /**
-         * List of file names for which to compute compiler errors.
-         * The files will be checked in list order.
-         */
         files: string[];
-        /**
-         * Delay in milliseconds to wait before starting to compute
-         * errors for the files in the file list
-         */
         delay: number;
     }
-    /**
-     * Geterr request; value of command field is "geterr". Wait for
-     * delay milliseconds and then, if during the wait no change or
-     * reload messages have arrived for the first file in the files
-     * list, get the syntactic errors for the file, field requests,
-     * and then get the semantic errors for the file.  Repeat with a
-     * smaller delay for each subsequent file on the files list.  Best
-     * practice for an editor is to send a file list containing each
-     * file that is currently visible, in most-recently-used order.
-     */
     interface GeterrRequest extends Request {
         command: CommandTypes.Geterr;
         arguments: GeterrRequestArgs;
     }
     type RequestCompletedEventName = "requestCompleted";
-    /**
-     * Event that is sent when server have finished processing request with specified id.
-     */
     interface RequestCompletedEvent extends Event {
         event: RequestCompletedEventName;
         body: RequestCompletedEventBody;
@@ -7231,78 +12935,31 @@ declare namespace ts.server.protocol {
     interface RequestCompletedEventBody {
         request_seq: number;
     }
-    /**
-     * Item of diagnostic information found in a DiagnosticEvent message.
-     */
     interface Diagnostic {
-        /**
-         * Starting file location at which text applies.
-         */
         start: Location;
-        /**
-         * The last file location at which the text applies.
-         */
         end: Location;
-        /**
-         * Text of diagnostic message.
-         */
         text: string;
-        /**
-         * The category of the diagnostic message, e.g. "error", "warning", or "suggestion".
-         */
         category: string;
         reportsUnnecessary?: {};
-        /**
-         * The error code of the diagnostic message.
-         */
         code?: number;
-        /**
-         * The name of the plugin reporting the message.
-         */
         source?: string;
     }
     interface DiagnosticWithFileName extends Diagnostic {
-        /**
-         * Name of the file the diagnostic is in
-         */
         fileName: string;
     }
     interface DiagnosticEventBody {
-        /**
-         * The file for which diagnostic information is reported.
-         */
         file: string;
-        /**
-         * An array of diagnostic information items.
-         */
         diagnostics: Diagnostic[];
     }
     type DiagnosticEventKind = "semanticDiag" | "syntaxDiag" | "suggestionDiag";
-    /**
-     * Event message for DiagnosticEventKind event types.
-     * These events provide syntactic and semantic errors for a file.
-     */
     interface DiagnosticEvent extends Event {
         body?: DiagnosticEventBody;
     }
     interface ConfigFileDiagnosticEventBody {
-        /**
-         * The file which trigged the searching and error-checking of the config file
-         */
         triggerFile: string;
-        /**
-         * The name of the found config file.
-         */
         configFile: string;
-        /**
-         * An arry of diagnostic information items for the found config file.
-         */
         diagnostics: DiagnosticWithFileName[];
     }
-    /**
-     * Event message for "configFileDiag" event type.
-     * This event provides errors for a found config file.
-     */
     interface ConfigFileDiagnosticEvent extends Event {
         body?: ConfigFileDiagnosticEventBody;
         event: "configFileDiag";
@@ -7313,17 +12970,7 @@ declare namespace ts.server.protocol {
         body?: ProjectLanguageServiceStateEventBody;
     }
     interface ProjectLanguageServiceStateEventBody {
-        /**
-         * Project name that has changes in the state of language service.
-         * For configured projects this will be the config file path.
-         * For external projects this will be the name of the projects specified when project was open.
-         * For inferred projects this event is not raised.
-         */
         projectName: string;
-        /**
-         * True if language service state switched from disabled to enabled
-         * and false otherwise.
-         */
         languageServiceEnabled: boolean;
     }
     type ProjectsUpdatedInBackgroundEventName = "projectsUpdatedInBackground";
@@ -7332,215 +12979,76 @@ declare namespace ts.server.protocol {
         body: ProjectsUpdatedInBackgroundEventBody;
     }
     interface ProjectsUpdatedInBackgroundEventBody {
-        /**
-         * Current set of open files
-         */
         openFiles: string[];
     }
-    /**
-     * Arguments for reload request.
-     */
     interface ReloadRequestArgs extends FileRequestArgs {
-        /**
-         * Name of temporary file from which to reload file
-         * contents. May be same as file.
-         */
         tmpfile: string;
     }
-    /**
-     * Reload request message; value of command field is "reload".
-     * Reload contents of file with name given by the 'file' argument
-     * from temporary file with name given by the 'tmpfile' argument.
-     * The two names can be identical.
-     */
     interface ReloadRequest extends FileRequest {
         command: CommandTypes.Reload;
         arguments: ReloadRequestArgs;
     }
-    /**
-     * Response to "reload" request. This is just an acknowledgement, so
-     * no body field is required.
-     */
     interface ReloadResponse extends Response {
     }
-    /**
-     * Arguments for saveto request.
-     */
     interface SavetoRequestArgs extends FileRequestArgs {
-        /**
-         * Name of temporary file into which to save server's view of
-         * file contents.
-         */
         tmpfile: string;
     }
-    /**
-     * Saveto request message; value of command field is "saveto".
-     * For debugging purposes, save to a temporaryfile (named by
-     * argument 'tmpfile') the contents of file named by argument
-     * 'file'.  The server does not currently send a response to a
-     * "saveto" request.
-     */
     interface SavetoRequest extends FileRequest {
         command: CommandTypes.Saveto;
         arguments: SavetoRequestArgs;
     }
-    /**
-     * Arguments for navto request message.
-     */
     interface NavtoRequestArgs extends FileRequestArgs {
-        /**
-         * Search term to navigate to from current location; term can
-         * be '.*' or an identifier prefix.
-         */
         searchValue: string;
-        /**
-         *  Optional limit on the number of items to return.
-         */
         maxResultCount?: number;
-        /**
-         * Optional flag to indicate we want results for just the current file
-         * or the entire project.
-         */
         currentFileOnly?: boolean;
         projectFileName?: string;
     }
-    /**
-     * Navto request message; value of command field is "navto".
-     * Return list of objects giving file locations and symbols that
-     * match the search term given in argument 'searchTerm'.  The
-     * context for the search is given by the named file.
-     */
     interface NavtoRequest extends FileRequest {
         command: CommandTypes.Navto;
         arguments: NavtoRequestArgs;
     }
-    /**
-     * An item found in a navto response.
-     */
     interface NavtoItem {
-        /**
-         * The symbol's name.
-         */
         name: string;
-        /**
-         * The symbol's kind (such as 'className' or 'parameterName').
-         */
         kind: ScriptElementKind;
-        /**
-         * exact, substring, or prefix.
-         */
         matchKind?: string;
-        /**
-         * If this was a case sensitive or insensitive match.
-         */
         isCaseSensitive?: boolean;
-        /**
-         * Optional modifiers for the kind (such as 'public').
-         */
         kindModifiers?: string;
-        /**
-         * The file in which the symbol is found.
-         */
         file: string;
-        /**
-         * The location within file at which the symbol is found.
-         */
         start: Location;
-        /**
-         * One past the last character of the symbol.
-         */
         end: Location;
-        /**
-         * Name of symbol's container symbol (if any); for example,
-         * the class name if symbol is a class member.
-         */
         containerName?: string;
-        /**
-         * Kind of symbol's container symbol (if any).
-         */
         containerKind?: ScriptElementKind;
     }
-    /**
-     * Navto response message. Body is an array of navto items.  Each
-     * item gives a symbol that matched the search term.
-     */
     interface NavtoResponse extends Response {
         body?: NavtoItem[];
     }
-    /**
-     * Arguments for change request message.
-     */
     interface ChangeRequestArgs extends FormatRequestArgs {
-        /**
-         * Optional string to insert at location (file, line, offset).
-         */
         insertString?: string;
     }
-    /**
-     * Change request message; value of command field is "change".
-     * Update the server's view of the file named by argument 'file'.
-     * Server does not currently send a response to a change request.
-     */
     interface ChangeRequest extends FileLocationRequest {
         command: CommandTypes.Change;
         arguments: ChangeRequestArgs;
     }
-    /**
-     * Response to "brace" request.
-     */
     interface BraceResponse extends Response {
         body?: TextSpan[];
     }
-    /**
-     * Brace matching request; value of command field is "brace".
-     * Return response giving the file locations of matching braces
-     * found in file at location line, offset.
-     */
     interface BraceRequest extends FileLocationRequest {
         command: CommandTypes.Brace;
     }
-    /**
-     * NavBar items request; value of command field is "navbar".
-     * Return response giving the list of navigation bar entries
-     * extracted from the requested file.
-     */
     interface NavBarRequest extends FileRequest {
         command: CommandTypes.NavBar;
     }
-    /**
-     * NavTree request; value of command field is "navtree".
-     * Return response giving the navigation tree of the requested file.
-     */
     interface NavTreeRequest extends FileRequest {
         command: CommandTypes.NavTree;
     }
     interface NavigationBarItem {
-        /**
-         * The item's display text.
-         */
         text: string;
-        /**
-         * The symbol's kind (such as 'className' or 'parameterName').
-         */
         kind: ScriptElementKind;
-        /**
-         * Optional modifiers for the kind (such as 'public').
-         */
         kindModifiers?: string;
-        /**
-         * The definition locations of the item.
-         */
         spans: TextSpan[];
-        /**
-         * Optional children.
-         */
         childItems?: NavigationBarItem[];
-        /**
-         * Number of levels deep this item should appear.
-         */
         indent: number;
     }
-    /** protocol.NavigationTree is identical to ts.NavigationTree, except using protocol.TextSpan instead of ts.TextSpan */
     interface NavigationTree {
         text: string;
         kind: ScriptElementKind;
@@ -7572,17 +13080,8 @@ declare namespace ts.server.protocol {
         payload: TypingsInstalledTelemetryEventPayload;
     }
     interface TypingsInstalledTelemetryEventPayload {
-        /**
-         * Comma separated list of installed typing packages
-         */
         installedPackages: string;
-        /**
-         * true if install request succeeded, otherwise - false
-         */
         installSuccess: boolean;
-        /**
-         * version of typings installer
-         */
         typingsInstallerVersion: string;
     }
     type BeginInstallTypesEventName = "beginInstallTypes";
@@ -7596,21 +13095,12 @@ declare namespace ts.server.protocol {
         body: EndInstallTypesEventBody;
     }
     interface InstallTypesEventBody {
-        /**
-         * correlation id to match begin and end events
-         */
         eventId: number;
-        /**
-         * list of packages to install
-         */
         packages: ReadonlyArray<string>;
     }
     interface BeginInstallTypesEventBody extends InstallTypesEventBody {
     }
     interface EndInstallTypesEventBody extends InstallTypesEventBody {
-        /**
-         * true if installation succeeded, otherwise false
-         */
         success: boolean;
     }
     interface NavBarResponse extends Response {
@@ -7653,15 +13143,7 @@ declare namespace ts.server.protocol {
     interface UserPreferences {
         readonly disableSuggestions?: boolean;
         readonly quotePreference?: "double" | "single";
-        /**
-         * If enabled, TypeScript will search through all external modules' exports and add them to the completions list.
-         * This affects lone identifier completions but not completions on the right hand side of `obj.`.
-         */
         readonly includeCompletionsForModuleExports?: boolean;
-        /**
-         * If enabled, the completion list will include completions with invalid identifier names.
-         * For those entries, The `insertText` and `replacementSpan` properties will be set to change from `.x` property access to `["x"]`.
-         */
         readonly includeCompletionsWithInsertText?: boolean;
         readonly importModuleSpecifierPreference?: "relative" | "non-relative";
         readonly allowTextChangesInNewFiles?: boolean;
@@ -7733,7 +13215,6 @@ declare namespace ts.server.protocol {
         traceResolution?: boolean;
         resolveJsonModule?: boolean;
         types?: string[];
-        /** Paths used to used to compute primary types search locations */
         typeRoots?: string[];
         [option: string]: CompilerOptionsValue | undefined;
     }
@@ -7772,25 +13253,65 @@ declare namespace ts.server.protocol {
     }
 }
 declare namespace ts.server {
+    class TextStorage {
+        private readonly host;
+        private readonly fileName;
+        private svc;
+        private svcVersion;
+        private text;
+        private lineMap;
+        private textVersion;
+        isOpen: boolean;
+        private ownFileText;
+        private pendingReloadFromDisk;
+        constructor(host: ServerHost, fileName: NormalizedPath);
+        getVersion(): string;
+        hasScriptVersionCache_TestOnly(): boolean;
+        useScriptVersionCache_TestOnly(): void;
+        useText(newText?: string): void;
+        edit(start: number, end: number, newText: string): void;
+        reload(newText: string): true | undefined;
+        reloadWithFileText(tempFileName?: string): true | undefined;
+        reloadFromDisk(): boolean | undefined;
+        delayReloadFromFileIntoText(): void;
+        getSnapshot(): IScriptSnapshot;
+        getLineInfo(line: number): AbsolutePositionAndLineText;
+        lineToTextSpan(line: number): TextSpan;
+        lineOffsetToPosition(line: number, offset: number): number;
+        positionToLineOffset(position: number): protocol.Location;
+        private getFileText;
+        private switchToScriptVersionCache;
+        private useScriptVersionCacheIfValidOrOpen;
+        private getOrLoadText;
+        private getLineMap;
+    }
+    function isDynamicFileName(fileName: NormalizedPath): boolean;
+    interface DocumentRegistrySourceFileCache {
+        key: DocumentRegistryBucketKey;
+        sourceFile: SourceFile;
+    }
     class ScriptInfo {
         private readonly host;
         readonly fileName: NormalizedPath;
         readonly scriptKind: ScriptKind;
         readonly hasMixedContent: boolean;
         readonly path: Path;
-        /**
-         * All projects that include this file
-         */
         readonly containingProjects: Project[];
         private formatSettings;
         private preferences;
+        fileWatcher: FileWatcher | undefined;
         private textStorage;
+        readonly isDynamic: boolean;
+        private realpath;
+        cacheSourceFile: DocumentRegistrySourceFileCache;
         constructor(host: ServerHost, fileName: NormalizedPath, scriptKind: ScriptKind, hasMixedContent: boolean, path: Path);
+        isDynamicOrHasMixedContent(): boolean;
         isScriptOpen(): boolean;
         open(newText: string): void;
         close(fileExists?: boolean): void;
         getSnapshot(): IScriptSnapshot;
         private ensureRealPath;
+        getRealpathIfDifferent(): Path | undefined;
         getFormatCodeSettings(): FormatCodeSettings | undefined;
         getPreferences(): UserPreferences | undefined;
         attachToProject(project: Project): boolean;
@@ -7802,18 +13323,13 @@ declare namespace ts.server {
         setOptions(formatSettings: FormatCodeSettings, preferences: UserPreferences | undefined): void;
         getLatestVersion(): string;
         saveTo(fileName: string): void;
+        delayReloadNonMixedContentFile(): void;
         reloadFromFile(tempFileName?: NormalizedPath): void;
+        getLineInfo(line: number): AbsolutePositionAndLineText;
         editContent(start: number, end: number, newText: string): void;
         markContainingProjectsAsDirty(): void;
         isOrphan(): boolean;
-        /**
-         *  @param line 1 based index
-         */
         lineToTextSpan(line: number): TextSpan;
-        /**
-         * @param line 1 based index
-         * @param offset 1 based index
-         */
         lineOffsetToPosition(line: number, offset: number): number;
         positionToLineOffset(position: number): protocol.Location;
         isJavaScript(): boolean;
@@ -7833,6 +13349,16 @@ declare namespace ts.server {
         readonly globalTypingsCacheLocation: string | undefined;
     }
     const nullTypingsInstaller: ITypingsInstaller;
+    class TypingsCache {
+        private readonly installer;
+        private readonly perProjectCache;
+        constructor(installer: ITypingsInstaller);
+        isKnownTypesPackageName(name: string): boolean;
+        installPackage(options: InstallPackageOptionsWithProject): Promise<ApplyCodeActionCommandResult>;
+        enqueueInstallTypingsForProject(project: Project, unresolvedImports: SortedReadonlyArray<string> | undefined, forceRefresh: boolean): void;
+        updateTypingsForProject(projectName: string, compilerOptions: CompilerOptions, typeAcquisition: TypeAcquisition, unresolvedImports: SortedReadonlyArray<string>, newTypings: string[]): SortedReadonlyArray<never> | SortedArray<string>;
+        onProjectClosed(project: Project): void;
+    }
 }
 declare namespace ts.server {
     enum ProjectKind {
@@ -7840,8 +13366,16 @@ declare namespace ts.server {
         Configured = 1,
         External = 2
     }
+    type Mutable<T> = {
+        -readonly [K in keyof T]: T[K];
+    };
+    function countEachFileTypes(infos: ScriptInfo[]): FileStats;
     function allRootFilesAreJsOrDts(project: Project): boolean;
     function allFilesAreJsOrDts(project: Project): boolean;
+    function hasNoTypeScriptSource(fileNames: string[]): boolean;
+    interface ProjectFilesWithTSDiagnostics extends protocol.ProjectFiles {
+        projectErrors: ReadonlyArray<Diagnostic>;
+    }
     interface PluginCreateInfo {
         project: Project;
         languageService: LanguageService;
@@ -7856,11 +13390,8 @@ declare namespace ts.server {
     type PluginModuleFactory = (mod: {
         typescript: typeof ts;
     }) => PluginModule;
-    /**
-     * The project root can be script info - if root is present,
-     * or it could be just normalized path if root wasnt present on the host(only for non inferred project)
-     */
     type ProjectRoot = ScriptInfo | NormalizedPath;
+    function isScriptInfo(value: ProjectRoot): value is ScriptInfo;
     abstract class Project implements LanguageServiceHost, ModuleResolutionHost {
         readonly projectName: string;
         readonly projectKind: ProjectKind;
@@ -7874,40 +13405,33 @@ declare namespace ts.server {
         private externalFiles;
         private missingFilesMap;
         private plugins;
+        cachedUnresolvedImportsPerFile: Map<ReadonlyArray<string>>;
+        lastCachedUnresolvedImportsList: SortedReadonlyArray<string> | undefined;
+        private hasAddedorRemovedFiles;
         private lastFileExceededProgramSize;
         protected languageService: LanguageService;
         languageServiceEnabled: boolean;
         readonly trace?: (s: string) => void;
         readonly realpath?: (path: string) => string;
+        hasInvalidatedResolution: HasInvalidatedResolution;
+        resolutionCache: ResolutionCache;
         private builderState;
-        /**
-         * Set of files names that were updated since the last call to getChangesSinceVersion.
-         */
         private updatedFileNames;
-        /**
-         * Set of files that was returned from the last call to getChangesSinceVersion.
-         */
         private lastReportedFileNames;
-        /**
-         * Last version that was reported.
-         */
         private lastReportedVersion;
-        /**
-         * Current project's program version. (incremented everytime new program is created that is not complete reuse from the old one)
-         * This property is changed in 'updateGraph' based on the set of files in program
-         */
         private projectProgramVersion;
-        /**
-         * Current version of the project state. It is changed when:
-         * - new root file was added/removed
-         * - edit happen in some file that is currently included in the project.
-         * This property is different from projectStructureVersion since in most cases edits don't affect set of files in the project
-         */
         private projectStateVersion;
+        dirty: boolean;
+        hasChangedAutomaticTypeDirectiveNames: boolean;
+        typingFiles: SortedReadonlyArray<string>;
         private readonly cancellationToken;
         isNonTsProject(): boolean;
         isJsOnlyProject(): boolean;
         static resolveModule(moduleName: string, initialDir: string, host: ServerHost, log: (message: string) => void): {} | undefined;
+        readonly currentDirectory: string;
+        directoryStructureHost: DirectoryStructureHost;
+        readonly getCanonicalFileName: GetCanonicalFileName;
+        constructor(projectName: string, projectKind: ProjectKind, projectService: ProjectService, documentRegistry: DocumentRegistry, hasExplicitListOfFiles: boolean, lastFileExceededProgramSize: string | undefined, compilerOptions: CompilerOptions, compileOnSaveEnabled: boolean, directoryStructureHost: DirectoryStructureHost, currentDirectory: string | undefined);
         isKnownTypesPackageName(name: string): boolean;
         installPackage(options: InstallPackageOptions): Promise<ApplyCodeActionCommandResult>;
         private readonly typingsCache;
@@ -7933,20 +13457,22 @@ declare namespace ts.server {
         resolveTypeReferenceDirectives(typeDirectiveNames: string[], containingFile: string): ResolvedTypeReferenceDirective[];
         directoryExists(path: string): boolean;
         getDirectories(path: string): string[];
+        getCachedDirectoryStructureHost(): CachedDirectoryStructureHost;
+        toPath(fileName: string): Path;
+        watchDirectoryOfFailedLookupLocation(directory: string, cb: DirectoryWatcherCallback, flags: WatchDirectoryFlags): FileWatcher;
+        onInvalidatedResolution(): void;
+        watchTypeRootsDirectory(directory: string, cb: DirectoryWatcherCallback, flags: WatchDirectoryFlags): FileWatcher;
+        onChangedAutomaticTypeDirectiveNames(): void;
+        getGlobalCache(): string | undefined;
+        writeLog(s: string): void;
         log(s: string): void;
         error(s: string): void;
         private setInternalCompilerOptionsForEmittingJsFiles;
-        /**
-         * Get the errors that dont have any file name associated
-         */
         getGlobalProjectErrors(): ReadonlyArray<Diagnostic>;
         getAllProjectErrors(): ReadonlyArray<Diagnostic>;
         getLanguageService(ensureSynchronized?: boolean): LanguageService;
         private shouldEmitFile;
         getCompileOnSaveAffectedFileList(scriptInfo: ScriptInfo): string[];
-        /**
-         * Returns true if emit was conducted
-         */
         emitFile(scriptInfo: ScriptInfo, writeFile: (path: string, data: string, writeByteOrderMark?: boolean) => void): boolean;
         enableLanguageService(): void;
         disableLanguageService(lastFileExceededProgramSize?: string): void;
@@ -7955,11 +13481,14 @@ declare namespace ts.server {
         protected removeLocalTypingsFromTypeAcquisition(newTypeAcquisition: TypeAcquisition): TypeAcquisition;
         getExternalFiles(): SortedReadonlyArray<string>;
         getSourceFile(path: Path): SourceFile | undefined;
+        getSourceFileOrConfigFile(path: Path): SourceFile | undefined;
         close(): void;
         private detachScriptInfoIfNotRoot;
         isClosed(): boolean;
         hasRoots(): boolean;
+        isOrphan(): boolean;
         getRootFiles(): NormalizedPath[];
+        getRootFilesMap(): Map<ProjectRoot>;
         getRootScriptInfos(): ScriptInfo[];
         getScriptInfos(): ScriptInfo[];
         getExcludedFiles(): ReadonlyArray<NormalizedPath>;
@@ -7973,11 +13502,11 @@ declare namespace ts.server {
         removeFile(info: ScriptInfo, fileExists: boolean, detachFromProject: boolean): void;
         registerFileUpdate(fileName: string): void;
         markAsDirty(): void;
-        /**
-         * Updates set of files that contribute to this project
-         * @returns: true if set of files in the project stays the same and false - otherwise.
-         */
+        private extractUnresolvedImportsFromSourceFile;
+        onFileAddedOrRemoved(): void;
         updateGraph(): boolean;
+        updateTypingFiles(typingFiles: SortedReadonlyArray<string>): void;
+        getCurrentProgram(): Program;
         protected removeExistingTypings(include: string[]): string[];
         private updateGraphWorker;
         private detachScriptInfoFromProject;
@@ -7987,76 +13516,66 @@ declare namespace ts.server {
         getScriptInfo(uncheckedFileName: string): ScriptInfo | undefined;
         filesToString(writeProjectFileNames: boolean): string;
         setCompilerOptions(compilerOptions: CompilerOptions): void;
+        getChangesSinceVersion(lastKnownVersion?: number): ProjectFilesWithTSDiagnostics;
         protected removeRoot(info: ScriptInfo): void;
         protected enableGlobalPlugins(): void;
         protected enablePlugin(pluginConfigEntry: PluginImport, searchPaths: string[]): void;
-        /** Starts a new check for diagnostics. Call this if some file has updated that would cause diagnostics to be changed. */
         refreshDiagnostics(): void;
         private enableProxy;
     }
-    /**
-     * If a file is opened and no tsconfig (or jsconfig) is found,
-     * the file and its imports/references are put into an InferredProject.
-     */
     class InferredProject extends Project {
         private static readonly newName;
         private _isJsInferredProject;
         toggleJsInferredProject(isJsInferredProject: boolean): void;
         setCompilerOptions(options?: CompilerOptions): void;
-        /** this is canonical project root path */
         readonly projectRootPath: string | undefined;
+        readonly canonicalCurrentDirectory: string | undefined;
+        constructor(projectService: ProjectService, documentRegistry: DocumentRegistry, compilerOptions: CompilerOptions, projectRootPath: NormalizedPath | undefined, currentDirectory: string | undefined);
         addRoot(info: ScriptInfo): void;
         removeRoot(info: ScriptInfo): void;
+        isOrphan(): boolean;
         isProjectWithSingleRoot(): boolean;
         close(): void;
         getTypeAcquisition(): TypeAcquisition;
     }
-    /**
-     * If a file is opened, the server will look for a tsconfig (or jsconfig)
-     * and if successfull create a ConfiguredProject for it.
-     * Otherwise it will create an InferredProject.
-     */
     class ConfiguredProject extends Project {
         compileOnSaveEnabled: boolean;
         private projectReferences;
         private typeAcquisition;
+        configFileWatcher: FileWatcher | undefined;
         private directoriesWatchedForWildcards;
         readonly canonicalConfigFilePath: NormalizedPath;
-        /** Ref count to the project when opened from external project */
+        pendingReload: ConfigFileProgramReloadLevel;
+        configFileSpecs: ConfigFileSpecs | undefined;
         private externalProjectRefCount;
         private projectErrors;
-        /**
-         * If the project has reload from disk pending, it reloads (and then updates graph as part of that) instead of just updating the graph
-         * @returns: true if set of files in the project stays the same and false - otherwise.
-         */
+        constructor(configFileName: NormalizedPath, projectService: ProjectService, documentRegistry: DocumentRegistry, hasExplicitListOfFiles: boolean, compilerOptions: CompilerOptions, lastFileExceededProgramSize: string | undefined, compileOnSaveEnabled: boolean, cachedDirectoryStructureHost: CachedDirectoryStructureHost, projectReferences: ReadonlyArray<ProjectReference> | undefined);
         updateGraph(): boolean;
+        getCachedDirectoryStructureHost(): CachedDirectoryStructureHost;
         getConfigFilePath(): NormalizedPath;
         getProjectReferences(): ReadonlyArray<ProjectReference> | undefined;
         updateReferences(refs: ReadonlyArray<ProjectReference> | undefined): void;
         enablePlugins(): void;
-        /**
-         * Get the errors that dont have any file name associated
-         */
         getGlobalProjectErrors(): ReadonlyArray<Diagnostic>;
-        /**
-         * Get all the project errors
-         */
         getAllProjectErrors(): ReadonlyArray<Diagnostic>;
         setProjectErrors(projectErrors: Diagnostic[]): void;
         setTypeAcquisition(newTypeAcquisition: TypeAcquisition): void;
         getTypeAcquisition(): TypeAcquisition;
+        watchWildcards(wildcardDirectories: Map<WatchDirectoryFlags>): void;
+        stopWatchingWildCards(): void;
         close(): void;
+        addExternalProjectReference(): void;
+        deleteExternalProjectReference(): void;
+        hasOpenRef(): boolean;
         getEffectiveTypeRoots(): string[];
+        updateErrorOnNoInputFiles(hasFileNames: boolean): void;
     }
-    /**
-     * Project whose configuration is handled externally, such as in a '.csproj'.
-     * These are created only if a host explicitly calls `openExternalProject`.
-     */
     class ExternalProject extends Project {
         externalProjectName: string;
         compileOnSaveEnabled: boolean;
         excludedFiles: ReadonlyArray<NormalizedPath>;
         private typeAcquisition;
+        constructor(externalProjectName: string, projectService: ProjectService, documentRegistry: DocumentRegistry, compilerOptions: CompilerOptions, lastFileExceededProgramSize: string | undefined, compileOnSaveEnabled: boolean, projectFilePath?: string);
         getExcludedFiles(): ReadonlyArray<NormalizedPath>;
         getTypeAcquisition(): TypeAcquisition;
         setTypeAcquisition(newTypeAcquisition: TypeAcquisition): void;
@@ -8090,20 +13609,13 @@ declare namespace ts.server {
             languageServiceEnabled: boolean;
         };
     }
-    /** This will be converted to the payload of a protocol.TelemetryEvent in session.defaultEventHandler. */
     interface ProjectInfoTelemetryEvent {
         readonly eventName: typeof ProjectInfoTelemetryEvent;
         readonly data: ProjectInfoTelemetryEventData;
     }
     interface ProjectInfoTelemetryEventData {
-        /** Cryptographically secure hash of project file location. */
         readonly projectId: string;
-        /** Count of file extensions seen in the project. */
         readonly fileStats: FileStats;
-        /**
-         * Any compiler options that might contain paths will be taken out.
-         * Enum compiler options will be converted to strings.
-         */
         readonly compilerOptions: CompilerOptions;
         readonly extends: boolean | undefined;
         readonly files: boolean | undefined;
@@ -8114,14 +13626,8 @@ declare namespace ts.server {
         readonly configFileName: "tsconfig.json" | "jsconfig.json" | "other";
         readonly projectType: "external" | "configured";
         readonly languageServiceEnabled: boolean;
-        /** TypeScript version used by the server. */
         readonly version: string;
     }
-    /**
-     * Info that we may send about a file that was just opened.
-     * Info about a file will only be sent once per session, even if the file changes in ways that might affect the info.
-     * Currently this is only sent for '.js' files.
-     */
     interface OpenFileInfoTelemetryEvent {
         readonly eventName: typeof OpenFileInfoTelemetryEvent;
         readonly data: OpenFileInfoTelemetryEventData;
@@ -8174,6 +13680,20 @@ declare namespace ts.server {
         configFileName?: NormalizedPath;
         configFileErrors?: ReadonlyArray<Diagnostic>;
     }
+    enum WatchType {
+        ConfigFilePath = "Config file for the program",
+        MissingFilePath = "Missing file from program",
+        WildcardDirectories = "Wild card directory",
+        ClosedScriptInfo = "Closed Script info",
+        ConfigFileForInferredRoot = "Config file for the inferred project root",
+        FailedLookupLocation = "Directory of Failed lookup locations in module resolution",
+        TypeRoots = "Type root directory"
+    }
+    interface ConfigFileExistenceInfo {
+        exists: boolean;
+        openFilesImpactedByConfigFile: Map<boolean>;
+        configFileWatcherForRootOfInferredProject?: FileWatcher;
+    }
     interface ProjectServiceOptions {
         host: ServerHost;
         logger: Logger;
@@ -8191,54 +13711,27 @@ declare namespace ts.server {
         syntaxOnly?: boolean;
     }
     class ProjectService {
-        /**
-         * Container of all known scripts
-         */
+        readonly typingsCache: TypingsCache;
+        readonly documentRegistry: DocumentRegistry;
         private readonly filenameToScriptInfo;
         private readonly allJsFilesForOpenFileTelemetry;
-        /**
-         * maps external project file name to list of config files that were the part of this project
-         */
+        readonly realpathToScriptInfos: MultiMap<ScriptInfo> | undefined;
         private readonly externalProjectToConfiguredProjectMap;
-        /**
-         * external projects (configuration and list of root files is not controlled by tsserver)
-         */
         readonly externalProjects: ExternalProject[];
-        /**
-         * projects built from openFileRoots
-         */
         readonly inferredProjects: InferredProject[];
-        /**
-         * projects specified by a tsconfig.json file
-         */
         readonly configuredProjects: Map<ConfiguredProject>;
-        /**
-         * Open files: with value being project root path, and key being Path of the file that is open
-         */
         readonly openFiles: Map<NormalizedPath | undefined>;
-        /**
-         * Map of open files that are opened without complete path but have projectRoot as current directory
-         */
         private readonly openFilesWithNonRootedDiskPath;
         private compilerOptionsForInferredProjects;
         private compilerOptionsForInferredProjectsPerProjectRoot;
-        /**
-         * Project size for configured or external projects
-         */
         private readonly projectToSizeMap;
-        /**
-         * This is a map of config file paths existance that doesnt need query to disk
-         * - The entry can be present because there is inferred project that needs to watch addition of config file to directory
-         *   In this case the exists could be true/false based on config file is present or not
-         * - Or it is present if we have configured project open with config file at that location
-         *   In this case the exists property is always true
-         */
         private readonly configFileExistenceInfoCache;
         private readonly throttledOperations;
         private readonly hostConfiguration;
         private safelist;
         private legacySafelist;
         private pendingProjectUpdates;
+        pendingEnsureProjectForOpenFiles: boolean;
         readonly currentDirectory: NormalizedPath;
         readonly toCanonicalFileName: (f: string) => string;
         readonly host: ServerHost;
@@ -8256,90 +13749,60 @@ declare namespace ts.server {
         readonly allowLocalPluginLoads: boolean;
         readonly typesMapLocation: string | undefined;
         readonly syntaxOnly?: boolean;
-        /** Tracks projects that we have already sent telemetry for. */
         private readonly seenProjects;
+        readonly watchFactory: WatchFactory<WatchType, Project>;
         constructor(opts: ProjectServiceOptions);
         toPath(fileName: string): Path;
+        getExecutingFilePath(): string;
+        getNormalizedAbsolutePath(fileName: string): string;
+        setDocument(key: DocumentRegistryBucketKey, path: Path, sourceFile: SourceFile): void;
+        getDocument(key: DocumentRegistryBucketKey, path: Path): SourceFile | undefined;
+        ensureInferredProjectsUpToDate_TestOnly(): void;
+        getCompilerOptionsForInferredProjects(): CompilerOptions;
+        onUpdateLanguageServiceStateForProject(project: Project, languageServiceEnabled: boolean): void;
         private loadTypesMap;
         updateTypingsForProject(response: SetTypings | InvalidateCachedTypings | PackageInstalledResponse): void;
+        updateTypingsForProject(response: SetTypings | InvalidateCachedTypings | PackageInstalledResponse | BeginInstallTypes | EndInstallTypes): void;
         private delayEnsureProjectForOpenFiles;
         private delayUpdateProjectGraph;
+        hasPendingProjectUpdate(project: Project): boolean;
+        sendProjectsUpdatedInBackgroundEvent(): void;
+        delayUpdateProjectGraphAndEnsureProjectStructureForOpenFiles(project: Project): void;
         private delayUpdateProjectGraphs;
         setCompilerOptionsForInferredProjects(projectCompilerOptions: protocol.ExternalProjectCompilerOptions, projectRootPath?: string): void;
         findProject(projectName: string): Project | undefined;
         getDefaultProjectForFile(fileName: NormalizedPath, ensureProject: boolean): Project | undefined;
         getScriptInfoEnsuringProjectsUptoDate(uncheckedFileName: string): ScriptInfo | undefined;
-        /**
-         * Ensures the project structures are upto date
-         * This means,
-         * - we go through all the projects and update them if they are dirty
-         * - if updates reflect some change in structure or there was pending request to ensure projects for open files
-         *   ensure that each open script info has project
-         */
         private ensureProjectStructuresUptoDate;
         getFormatCodeOptions(file: NormalizedPath): FormatCodeSettings;
         getPreferences(file: NormalizedPath): UserPreferences;
         private onSourceFileChanged;
         private handleDeletedFile;
+        watchWildcardDirectory(directory: Path, flags: WatchDirectoryFlags, project: ConfiguredProject): FileWatcher;
+        getConfigFileExistenceInfo(project: ConfiguredProject): ConfigFileExistenceInfo;
         private onConfigChangedForConfiguredProject;
-        /**
-         * This is the callback function for the config file add/remove/change at any location
-         * that matters to open script info but doesnt have configured project open
-         * for the config file
-         */
         private onConfigFileChangeForOpenScriptInfo;
         private removeProject;
-        /**
-         * Remove this file from the set of open, non-configured files.
-         * @param info The file that has been closed or newly configured
-         */
+        assignOrphanScriptInfoToInferredProject(info: ScriptInfo, projectRootPath: NormalizedPath | undefined): InferredProject;
         private closeOpenFile;
         private deleteScriptInfo;
         private configFileExists;
         private setConfigFileExistenceByNewConfiguredProject;
-        /**
-         * Returns true if the configFileExistenceInfo is needed/impacted by open files that are root of inferred project
-         */
         private configFileExistenceImpactsRootOfInferredProject;
         private setConfigFileExistenceInfoByClosedConfiguredProject;
         private logConfigFileWatchUpdate;
-        /**
-         * Create the watcher for the configFileExistenceInfo
-         */
         private createConfigFileWatcherOfConfigFileExistence;
-        /**
-         * Close the config file watcher in the cached ConfigFileExistenceInfo
-         *   if there arent any open files that are root of inferred project
-         */
         private closeConfigFileWatcherOfConfigFileExistenceInfo;
-        /**
-         * This is called on file close, so that we stop watching the config file for this script info
-         */
         private stopWatchingConfigFilesForClosedScriptInfo;
-        /**
-         * This function tries to search for a tsconfig.json for the given file.
-         * This is different from the method the compiler uses because
-         * the compiler can assume it will always start searching in the
-         * current directory (the directory in which tsc was invoked).
-         * The server must start searching from the directory containing
-         * the newly opened file.
-         */
+        startWatchingConfigFilesForInferredProjectRoot(info: ScriptInfo): void;
+        stopWatchingConfigFilesForInferredProjectRoot(info: ScriptInfo): void;
         private forEachConfigFileLocation;
-        /**
-         * This function tries to search for a tsconfig.json for the given file.
-         * This is different from the method the compiler uses because
-         * the compiler can assume it will always start searching in the
-         * current directory (the directory in which tsc was invoked).
-         * The server must start searching from the directory containing
-         * the newly opened file.
-         */
         private getConfigFileNameForFile;
         private printProjects;
         private findConfiguredProjectByProjectName;
         private getConfiguredProjectByCanonicalConfigFilePath;
         private findExternalProjectByProjectName;
         private convertConfigFileContentToProjectOptions;
-        /** Get a filename if the language service exceeds the maximum allowed program size; otherwise returns undefined. */
         private getFilenameForExceededTotalSizeLimitForNonTsFiles;
         private createExternalProject;
         private sendProjectTelemetry;
@@ -8347,70 +13810,45 @@ declare namespace ts.server {
         private createConfiguredProject;
         private updateNonInferredProjectFiles;
         private updateNonInferredProject;
+        reloadFileNamesOfConfiguredProject(project: ConfiguredProject): boolean;
+        reloadConfiguredProject(project: ConfiguredProject): void;
         private sendConfigFileDiagEvent;
         private getOrCreateInferredProjectForProjectRootPathIfEnabled;
         private getOrCreateSingleInferredProjectIfEnabled;
         private getOrCreateSingleInferredWithoutProjectRoot;
         private createInferredProject;
+        getOrCreateScriptInfoNotOpenedByClient(uncheckedFileName: string, currentDirectory: string, hostToQueryFileExistsOn: DirectoryStructureHost): ScriptInfo | undefined;
         getScriptInfo(uncheckedFileName: string): ScriptInfo | undefined;
+        getSymlinkedProjects(info: ScriptInfo): MultiMap<Project> | undefined;
         private watchClosedScriptInfo;
         private stopWatchingScriptInfo;
+        getOrCreateScriptInfoNotOpenedByClientForNormalizedPath(fileName: NormalizedPath, currentDirectory: string, scriptKind: ScriptKind | undefined, hasMixedContent: boolean | undefined, hostToQueryFileExistsOn: DirectoryStructureHost | undefined): ScriptInfo | undefined;
+        getOrCreateScriptInfoOpenedByClientForNormalizedPath(fileName: NormalizedPath, currentDirectory: string, fileContent: string | undefined, scriptKind: ScriptKind | undefined, hasMixedContent: boolean | undefined): ScriptInfo | undefined;
         getOrCreateScriptInfoForNormalizedPath(fileName: NormalizedPath, openedByClient: boolean, fileContent?: string, scriptKind?: ScriptKind, hasMixedContent?: boolean, hostToQueryFileExistsOn?: {
             fileExists(path: string): boolean;
         }): ScriptInfo | undefined;
         private getOrCreateScriptInfoWorker;
-        /**
-         * This gets the script info for the normalized path. If the path is not rooted disk path then the open script info with project root context is preferred
-         */
         getScriptInfoForNormalizedPath(fileName: NormalizedPath): ScriptInfo | undefined;
         getScriptInfoForPath(fileName: Path): ScriptInfo | undefined;
         setHostConfiguration(args: protocol.ConfigureRequestArguments): void;
         closeLog(): void;
-        /**
-         * This function rebuilds the project for every file opened by the client
-         * This does not reload contents of open files from disk. But we could do that if needed
-         */
         reloadProjects(): void;
         private delayReloadConfiguredProjectForFiles;
-        /**
-         * This function goes through all the openFiles and tries to file the config file for them.
-         * If the config file is found and it refers to existing project, it reloads it either immediately
-         * or schedules it for reload depending on delayReload option
-         * If the there is no existing project it just opens the configured project for the config file
-         * reloadForInfo provides a way to filter out files to reload configured project for
-         */
         private reloadConfiguredProjectForFiles;
-        /**
-         * Remove the root of inferred project if script info is part of another project
-         */
         private removeRootOfInferredProjectIfNowPartOfOtherProject;
-        /**
-         * This function is to update the project structure for every inferred project.
-         * It is called on the premise that all the configured projects are
-         * up to date.
-         * This will go through open files and assign them to inferred project if open file is not part of any other project
-         * After that all the inferred project graphs are updated
-         */
         private ensureProjectForOpenFiles;
-        /**
-         * Open file whose contents is managed by the client
-         * @param filename is absolute pathname
-         * @param fileContent is a known version of the file content that is more up to date than the one on disk
-         */
         openClientFile(fileName: string, fileContent?: string, scriptKind?: ScriptKind, projectRootPath?: string): OpenConfiguredProjectResult;
         private findExternalProjectContainingOpenScriptInfo;
         openClientFileWithNormalizedPath(fileName: NormalizedPath, fileContent?: string, scriptKind?: ScriptKind, hasMixedContent?: boolean, projectRootPath?: NormalizedPath): OpenConfiguredProjectResult;
         private telemetryOnOpenFile;
-        /**
-         * Close file whose contents is managed by the client
-         * @param filename is absolute pathname
-         */
         closeClientFile(uncheckedFileName: string): void;
         private collectChanges;
+        synchronizeProjectList(knownProjects: protocol.ProjectVersionInfo[]): ProjectFilesWithTSDiagnostics[];
+        applyChangesInOpenFiles(openFiles: protocol.ExternalFile[] | undefined, changedFiles: protocol.ChangedOpenFile[] | undefined, closedFiles: string[] | undefined): void;
+        applyChangesToFile(scriptInfo: ScriptInfo, changes: TextChange[]): void;
         private closeConfiguredProjectReferencedFromExternalProject;
         closeExternalProject(uncheckedFileName: string): void;
         openExternalProjects(projects: protocol.ExternalProject[]): void;
-        /** Makes a filename safe to insert in a RegExp */
         private static readonly filenameEscapeRegexp;
         private static escapeFilenameForRegex;
         resetSafeList(): void;
@@ -8436,6 +13874,7 @@ declare namespace ts.server {
     interface EventSender {
         event: Event;
     }
+    function toEvent(eventName: string, body: object): protocol.Event;
     interface SessionOptions {
         host: ServerHost;
         cancellationToken: ServerCancellationToken;
@@ -8445,12 +13884,8 @@ declare namespace ts.server {
         byteLength: (buf: string, encoding?: string) => number;
         hrtime: (start?: number[]) => number[];
         logger: Logger;
-        /**
-         * If falsy, all events are suppressed.
-         */
         canUseEvents: boolean;
         eventHandler?: ProjectServiceEventHandler;
-        /** Has no effect if eventHandler is also specified. */
         suppressDiagnosticEvents?: boolean;
         syntaxOnly?: boolean;
         throttleWaitMilliseconds?: number;
@@ -8482,14 +13917,12 @@ declare namespace ts.server {
         logError(err: Error, cmd: string): void;
         send(msg: protocol.Message): void;
         event<T extends object>(body: T, eventName: string): void;
-        /** @deprecated */
         output(info: any, cmdName: string, reqSeq?: number, errorMsg?: string): void;
         private doOutput;
         private semanticCheck;
         private syntacticCheck;
         private suggestionCheck;
         private sendDiagnosticsEvent;
-        /** It is the caller's responsibility to verify that `!this.suppressDiagnosticEvents`. */
         private updateErrorCheck;
         private cleanProjects;
         private cleanup;
@@ -8522,10 +13955,6 @@ declare namespace ts.server {
         private getDefaultProject;
         private getRenameLocations;
         private getReferences;
-        /**
-         * @param fileName is the name of the file to be opened
-         * @param fileContent is a version of the file content that is known to be more up to date than the one on disk
-         */
         private openClientFile;
         private getPosition;
         private getPositionInFile;
@@ -8598,7 +14027,110 @@ declare namespace ts.server {
         response?: {};
         responseRequired?: boolean;
     }
+    function getLocationInNewDocument(oldText: string, renameFilename: string, renameLocation: number, edits: ReadonlyArray<FileTextChanges>): protocol.Location;
 }
-
+declare namespace ts.server {
+    interface LineCollection {
+        charCount(): number;
+        lineCount(): number;
+        isLeaf(): this is LineLeaf;
+        walk(rangeStart: number, rangeLength: number, walkFns: LineIndexWalker): void;
+    }
+    interface AbsolutePositionAndLineText {
+        absolutePosition: number;
+        lineText: string | undefined;
+    }
+    enum CharRangeSection {
+        PreStart = 0,
+        Start = 1,
+        Entire = 2,
+        Mid = 3,
+        End = 4,
+        PostEnd = 5
+    }
+    interface LineIndexWalker {
+        goSubtree: boolean;
+        done: boolean;
+        leaf(relativeStart: number, relativeLength: number, lineCollection: LineLeaf): void;
+        pre?(relativeStart: number, relativeLength: number, lineCollection: LineCollection, parent: LineNode, nodeType: CharRangeSection): void;
+        post?(relativeStart: number, relativeLength: number, lineCollection: LineCollection, parent: LineNode, nodeType: CharRangeSection): void;
+    }
+    class ScriptVersionCache {
+        private changes;
+        private readonly versions;
+        private minVersion;
+        private currentVersion;
+        private static readonly changeNumberThreshold;
+        private static readonly changeLengthThreshold;
+        private static readonly maxVersions;
+        private versionToIndex;
+        private currentVersionToIndex;
+        edit(pos: number, deleteLen: number, insertedText?: string): void;
+        getSnapshot(): IScriptSnapshot;
+        private _getSnapshot;
+        getSnapshotVersion(): number;
+        getLineInfo(line: number): AbsolutePositionAndLineText;
+        lineOffsetToPosition(line: number, column: number): number;
+        positionToLineOffset(position: number): protocol.Location;
+        lineToTextSpan(line: number): TextSpan;
+        getTextChangesBetweenVersions(oldVersion: number, newVersion: number): TextChangeRange | undefined;
+        static fromString(script: string): ScriptVersionCache;
+    }
+    class LineIndex {
+        root: LineNode;
+        checkEdits: boolean;
+        absolutePositionOfStartOfLine(oneBasedLine: number): number;
+        positionToLineOffset(position: number): protocol.Location;
+        private positionToColumnAndLineText;
+        lineNumberToInfo(oneBasedLine: number): AbsolutePositionAndLineText;
+        load(lines: string[]): void;
+        walk(rangeStart: number, rangeLength: number, walkFns: LineIndexWalker): void;
+        getText(rangeStart: number, rangeLength: number): string;
+        getLength(): number;
+        every(f: (ll: LineLeaf, s: number, len: number) => boolean, rangeStart: number, rangeEnd?: number): boolean;
+        edit(pos: number, deleteLength: number, newText?: string): LineIndex;
+        private static buildTreeFromBottom;
+        static linesFromText(text: string): {
+            lines: string[];
+            lineMap: number[];
+        };
+    }
+    class LineNode implements LineCollection {
+        private readonly children;
+        totalChars: number;
+        totalLines: number;
+        constructor(children?: LineCollection[]);
+        isLeaf(): boolean;
+        updateCounts(): void;
+        private execWalk;
+        private skipChild;
+        walk(rangeStart: number, rangeLength: number, walkFns: LineIndexWalker): void;
+        charOffsetToLineInfo(lineNumberAccumulator: number, relativePosition: number): {
+            oneBasedLine: number;
+            zeroBasedColumn: number;
+            lineText: string | undefined;
+        };
+        lineNumberToInfo(relativeOneBasedLine: number, positionAccumulator: number): {
+            position: number;
+            leaf: LineLeaf | undefined;
+        };
+        private splitAfter;
+        remove(child: LineCollection): void;
+        private findChildIndex;
+        insertAt(child: LineCollection, nodes: LineCollection[]): LineNode[];
+        add(collection: LineCollection): void;
+        charCount(): number;
+        lineCount(): number;
+    }
+    class LineLeaf implements LineCollection {
+        text: string;
+        constructor(text: string);
+        isLeaf(): boolean;
+        walk(rangeStart: number, rangeLength: number, walkFns: LineIndexWalker): void;
+        charCount(): number;
+        lineCount(): number;
+    }
+}
+//# sourceMappingURL=server.d.ts.map
 export = ts;
 export as namespace ts;
\ No newline at end of file
diff --git a/lib/typescript.d.ts b/lib/typescript.d.ts
index acbcabf5bef..c195146831d 100644
--- a/lib/typescript.d.ts
+++ b/lib/typescript.d.ts
@@ -13,6 +13,12 @@ See the Apache Version 2.0 License for specific language governing permissions
 and limitations under the License.
 ***************************************************************************** */
 
+
+declare namespace ts {
+    const versionMajorMinor = "3.0";
+    /** The version of the TypeScript compiler release */
+    const version: string;
+}
 declare namespace ts {
     /**
      * Type of objects whose values are all of the same type.
@@ -22,6 +28,9 @@ declare namespace ts {
     interface MapLike<T> {
         [index: string]: T;
     }
+    interface SortedArray<T> extends Array<T> {
+        " __sortedArrayBrand": any;
+    }
     /** ES6 Map interface, only read methods included. */
     interface ReadonlyMap<T> {
         get(key: string): T | undefined;
@@ -52,6 +61,8 @@ declare namespace ts {
     interface Push<T> {
         push(...values: T[]): void;
     }
+}
+declare namespace ts {
     type Path = string & {
         __pathBrand: any;
     };
@@ -2071,7 +2082,7 @@ declare namespace ts {
         AliasExcludes = 2097152,
         ModuleMember = 2623475,
         ExportHasLocal = 944,
-        HasExports = 1952,
+        HasExports = 1955,
         HasMembers = 6240,
         BlockScoped = 418,
         PropertyOrAccessor = 98308,
@@ -2906,9 +2917,6 @@ declare namespace ts {
         span: TextSpan;
         newLength: number;
     }
-    interface SortedArray<T> extends Array<T> {
-        " __sortedArrayBrand": any;
-    }
     interface SyntaxList extends Node {
         _children: Node[];
     }
@@ -2978,15 +2986,6 @@ declare namespace ts {
         IndexSignatureParameters = 4432
     }
 }
-declare namespace ts {
-    const versionMajorMinor = "3.0";
-    /** The version of the TypeScript compiler release */
-    const version: string;
-}
-declare namespace ts {
-    function isExternalModuleNameRelative(moduleName: string): boolean;
-    function sortAndDeduplicateDiagnostics<T extends Diagnostic>(diagnostics: ReadonlyArray<T>): T[];
-}
 declare function setTimeout(handler: (...args: any[]) => void, timeout: number): any;
 declare function clearTimeout(handle: any): void;
 declare namespace ts {
@@ -3099,6 +3098,11 @@ declare namespace ts {
     function isIdentifierPart(ch: number, languageVersion: ScriptTarget | undefined): boolean;
     function createScanner(languageVersion: ScriptTarget, skipTrivia: boolean, languageVariant?: LanguageVariant, textInitial?: string, onError?: ErrorCallback, start?: number, length?: number): Scanner;
 }
+/** Non-internal stuff goes here */
+declare namespace ts {
+    function isExternalModuleNameRelative(moduleName: string): boolean;
+    function sortAndDeduplicateDiagnostics<T extends Diagnostic>(diagnostics: ReadonlyArray<T>): T[];
+}
 declare namespace ts {
     function getDefaultLibFileName(options: CompilerOptions): string;
     function textSpanEnd(span: TextSpan): number;
@@ -3484,6 +3488,79 @@ declare namespace ts {
     function isExternalModule(file: SourceFile): boolean;
     function updateSourceFile(sourceFile: SourceFile, newText: string, textChangeRange: TextChangeRange, aggressiveChecks?: boolean): SourceFile;
 }
+declare namespace ts {
+    function parseCommandLine(commandLine: ReadonlyArray<string>, readFile?: (path: string) => string | undefined): ParsedCommandLine;
+    type DiagnosticReporter = (diagnostic: Diagnostic) => void;
+    /**
+     * Reports config file diagnostics
+     */
+    interface ConfigFileDiagnosticsReporter {
+        /**
+         * Reports unrecoverable error when parsing config file
+         */
+        onUnRecoverableConfigFileDiagnostic: DiagnosticReporter;
+    }
+    /**
+     * Interface extending ParseConfigHost to support ParseConfigFile that reads config file and reports errors
+     */
+    interface ParseConfigFileHost extends ParseConfigHost, ConfigFileDiagnosticsReporter {
+        getCurrentDirectory(): string;
+    }
+    /**
+     * Reads the config file, reports errors if any and exits if the config file cannot be found
+     */
+    function getParsedCommandLineOfConfigFile(configFileName: string, optionsToExtend: CompilerOptions, host: ParseConfigFileHost): ParsedCommandLine | undefined;
+    /**
+     * Read tsconfig.json file
+     * @param fileName The path to the config file
+     */
+    function readConfigFile(fileName: string, readFile: (path: string) => string | undefined): {
+        config?: any;
+        error?: Diagnostic;
+    };
+    /**
+     * Parse the text of the tsconfig.json file
+     * @param fileName The path to the config file
+     * @param jsonText The text of the config file
+     */
+    function parseConfigFileTextToJson(fileName: string, jsonText: string): {
+        config?: any;
+        error?: Diagnostic;
+    };
+    /**
+     * Read tsconfig.json file
+     * @param fileName The path to the config file
+     */
+    function readJsonConfigFile(fileName: string, readFile: (path: string) => string | undefined): TsConfigSourceFile;
+    /**
+     * Convert the json syntax tree into the json value
+     */
+    function convertToObject(sourceFile: JsonSourceFile, errors: Push<Diagnostic>): any;
+    /**
+     * Parse the contents of a config file (tsconfig.json).
+     * @param json The contents of the config file to parse
+     * @param host Instance of ParseConfigHost used to enumerate files in folder.
+     * @param basePath A root directory to resolve relative path entries in the config
+     *    file to. e.g. outDir
+     */
+    function parseJsonConfigFileContent(json: any, host: ParseConfigHost, basePath: string, existingOptions?: CompilerOptions, configFileName?: string, resolutionStack?: Path[], extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): ParsedCommandLine;
+    /**
+     * Parse the contents of a config file (tsconfig.json).
+     * @param jsonNode The contents of the config file to parse
+     * @param host Instance of ParseConfigHost used to enumerate files in folder.
+     * @param basePath A root directory to resolve relative path entries in the config
+     *    file to. e.g. outDir
+     */
+    function parseJsonSourceFileConfigFileContent(sourceFile: TsConfigSourceFile, host: ParseConfigHost, basePath: string, existingOptions?: CompilerOptions, configFileName?: string, resolutionStack?: Path[], extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): ParsedCommandLine;
+    function convertCompilerOptionsFromJson(jsonOptions: any, basePath: string, configFileName?: string): {
+        options: CompilerOptions;
+        errors: Diagnostic[];
+    };
+    function convertTypeAcquisitionFromJson(jsonOptions: any, basePath: string, configFileName?: string): {
+        options: TypeAcquisition;
+        errors: Diagnostic[];
+    };
+}
 declare namespace ts {
     function getEffectiveTypeRoots(options: CompilerOptions, host: GetEffectiveTypeRootsHost): string[] | undefined;
     /**
@@ -4311,76 +4388,179 @@ declare namespace ts {
     function createWatchProgram<T extends BuilderProgram>(host: WatchCompilerHostOfConfigFile<T>): WatchOfConfigFile<T>;
 }
 declare namespace ts {
-    function parseCommandLine(commandLine: ReadonlyArray<string>, readFile?: (path: string) => string | undefined): ParsedCommandLine;
-    type DiagnosticReporter = (diagnostic: Diagnostic) => void;
     /**
-     * Reports config file diagnostics
+     * Branded string for keeping track of when we've turned an ambiguous path
+     * specified like "./blah" to an absolute path to an actual
+     * tsconfig file, e.g. "/root/blah/tsconfig.json"
      */
-    interface ConfigFileDiagnosticsReporter {
+    type ResolvedConfigFileName = string & {
+        _isResolvedConfigFileName: never;
+    };
+    interface BuildHost {
+        verbose(diag: DiagnosticMessage, ...args: string[]): void;
+        error(diag: DiagnosticMessage, ...args: string[]): void;
+        errorDiagnostic(diag: Diagnostic): void;
+        message(diag: DiagnosticMessage, ...args: string[]): void;
+    }
+    /**
+     * A BuildContext tracks what's going on during the course of a build.
+     *
+     * Callers may invoke any number of build requests within the same context;
+     * until the context is reset, each project will only be built at most once.
+     *
+     * Example: In a standard setup where project B depends on project A, and both are out of date,
+     * a failed build of A will result in A remaining out of date. When we try to build
+     * B, we should immediately bail instead of recomputing A's up-to-date status again.
+     *
+     * This also matters for performing fast (i.e. fake) downstream builds of projects
+     * when their upstream .d.ts files haven't changed content (but have newer timestamps)
+     */
+    interface BuildContext {
+        options: BuildOptions;
         /**
-         * Reports unrecoverable error when parsing config file
+         * Map from output file name to its pre-build timestamp
          */
-        onUnRecoverableConfigFileDiagnostic: DiagnosticReporter;
+        unchangedOutputs: FileMap<Date>;
+        /**
+         * Map from config file name to up-to-date status
+         */
+        projectStatus: FileMap<UpToDateStatus>;
+        invalidatedProjects: FileMap<true>;
+        queuedProjects: FileMap<true>;
+        missingRoots: Map<true>;
     }
-    /**
-     * Interface extending ParseConfigHost to support ParseConfigFile that reads config file and reports errors
-     */
-    interface ParseConfigFileHost extends ParseConfigHost, ConfigFileDiagnosticsReporter {
-        getCurrentDirectory(): string;
+    type Mapper = ReturnType<typeof createDependencyMapper>;
+    interface DependencyGraph {
+        buildQueue: ResolvedConfigFileName[];
+        dependencyMap: Mapper;
     }
-    /**
-     * Reads the config file, reports errors if any and exits if the config file cannot be found
-     */
-    function getParsedCommandLineOfConfigFile(configFileName: string, optionsToExtend: CompilerOptions, host: ParseConfigFileHost): ParsedCommandLine | undefined;
-    /**
-     * Read tsconfig.json file
-     * @param fileName The path to the config file
-     */
-    function readConfigFile(fileName: string, readFile: (path: string) => string | undefined): {
-        config?: any;
-        error?: Diagnostic;
+    interface BuildOptions {
+        dry: boolean;
+        force: boolean;
+        verbose: boolean;
+    }
+    enum UpToDateStatusType {
+        Unbuildable = 0,
+        UpToDate = 1,
+        /**
+         * The project appears out of date because its upstream inputs are newer than its outputs,
+         * but all of its outputs are actually newer than the previous identical outputs of its (.d.ts) inputs.
+         * This means we can Pseudo-build (just touch timestamps), as if we had actually built this project.
+         */
+        UpToDateWithUpstreamTypes = 2,
+        OutputMissing = 3,
+        OutOfDateWithSelf = 4,
+        OutOfDateWithUpstream = 5,
+        UpstreamOutOfDate = 6,
+        UpstreamBlocked = 7,
+        /**
+         * Projects with no outputs (i.e. "solution" files)
+         */
+        ContainerOnly = 8
+    }
+    type UpToDateStatus = Status.Unbuildable | Status.UpToDate | Status.OutputMissing | Status.OutOfDateWithSelf | Status.OutOfDateWithUpstream | Status.UpstreamOutOfDate | Status.UpstreamBlocked | Status.ContainerOnly;
+    namespace Status {
+        /**
+         * The project can't be built at all in its current state. For example,
+         * its config file cannot be parsed, or it has a syntax error or missing file
+         */
+        interface Unbuildable {
+            type: UpToDateStatusType.Unbuildable;
+            reason: string;
+        }
+        /**
+         * This project doesn't have any outputs, so "is it up to date" is a meaningless question.
+         */
+        interface ContainerOnly {
+            type: UpToDateStatusType.ContainerOnly;
+        }
+        /**
+         * The project is up to date with respect to its inputs.
+         * We track what the newest input file is.
+         */
+        interface UpToDate {
+            type: UpToDateStatusType.UpToDate | UpToDateStatusType.UpToDateWithUpstreamTypes;
+            newestInputFileTime: Date;
+            newestInputFileName: string;
+            newestDeclarationFileContentChangedTime: Date;
+            newestOutputFileTime: Date;
+            newestOutputFileName: string;
+            oldestOutputFileName: string;
+        }
+        /**
+         * One or more of the outputs of the project does not exist.
+         */
+        interface OutputMissing {
+            type: UpToDateStatusType.OutputMissing;
+            /**
+             * The name of the first output file that didn't exist
+             */
+            missingOutputFileName: string;
+        }
+        /**
+         * One or more of the project's outputs is older than its newest input.
+         */
+        interface OutOfDateWithSelf {
+            type: UpToDateStatusType.OutOfDateWithSelf;
+            outOfDateOutputFileName: string;
+            newerInputFileName: string;
+        }
+        /**
+         * This project depends on an out-of-date project, so shouldn't be built yet
+         */
+        interface UpstreamOutOfDate {
+            type: UpToDateStatusType.UpstreamOutOfDate;
+            upstreamProjectName: string;
+        }
+        /**
+         * This project depends an upstream project with build errors
+         */
+        interface UpstreamBlocked {
+            type: UpToDateStatusType.UpstreamBlocked;
+            upstreamProjectName: string;
+        }
+        /**
+         * One or more of the project's outputs is older than the newest output of
+         * an upstream project.
+         */
+        interface OutOfDateWithUpstream {
+            type: UpToDateStatusType.OutOfDateWithUpstream;
+            outOfDateOutputFileName: string;
+            newerProjectName: string;
+        }
+    }
+    interface FileMap<T> {
+        setValue(fileName: string, value: T): void;
+        getValue(fileName: string): T | never;
+        getValueOrUndefined(fileName: string): T | undefined;
+        hasKey(fileName: string): boolean;
+        removeKey(fileName: string): void;
+        getKeys(): string[];
+    }
+    function createDependencyMapper(): {
+        addReference: (childConfigFileName: ResolvedConfigFileName, parentConfigFileName: ResolvedConfigFileName) => void;
+        getReferencesTo: (parentConfigFileName: ResolvedConfigFileName) => ResolvedConfigFileName[];
+        getReferencesOf: (childConfigFileName: ResolvedConfigFileName) => ResolvedConfigFileName[];
+        getKeys: () => ReadonlyArray<ResolvedConfigFileName>;
     };
+    function createBuildContext(options: BuildOptions): BuildContext;
+    function performBuild(args: string[], compilerHost: CompilerHost, buildHost: BuildHost, system?: System): number | undefined;
     /**
-     * Parse the text of the tsconfig.json file
-     * @param fileName The path to the config file
-     * @param jsonText The text of the config file
+     * A SolutionBuilder has an immutable set of rootNames that are the "entry point" projects, but
+     * can dynamically add/remove other projects based on changes on the rootNames' references
      */
-    function parseConfigFileTextToJson(fileName: string, jsonText: string): {
-        config?: any;
-        error?: Diagnostic;
-    };
-    /**
-     * Read tsconfig.json file
-     * @param fileName The path to the config file
-     */
-    function readJsonConfigFile(fileName: string, readFile: (path: string) => string | undefined): TsConfigSourceFile;
-    /**
-     * Convert the json syntax tree into the json value
-     */
-    function convertToObject(sourceFile: JsonSourceFile, errors: Push<Diagnostic>): any;
-    /**
-     * Parse the contents of a config file (tsconfig.json).
-     * @param json The contents of the config file to parse
-     * @param host Instance of ParseConfigHost used to enumerate files in folder.
-     * @param basePath A root directory to resolve relative path entries in the config
-     *    file to. e.g. outDir
-     */
-    function parseJsonConfigFileContent(json: any, host: ParseConfigHost, basePath: string, existingOptions?: CompilerOptions, configFileName?: string, resolutionStack?: Path[], extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): ParsedCommandLine;
-    /**
-     * Parse the contents of a config file (tsconfig.json).
-     * @param jsonNode The contents of the config file to parse
-     * @param host Instance of ParseConfigHost used to enumerate files in folder.
-     * @param basePath A root directory to resolve relative path entries in the config
-     *    file to. e.g. outDir
-     */
-    function parseJsonSourceFileConfigFileContent(sourceFile: TsConfigSourceFile, host: ParseConfigHost, basePath: string, existingOptions?: CompilerOptions, configFileName?: string, resolutionStack?: Path[], extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): ParsedCommandLine;
-    function convertCompilerOptionsFromJson(jsonOptions: any, basePath: string, configFileName?: string): {
-        options: CompilerOptions;
-        errors: Diagnostic[];
-    };
-    function convertTypeAcquisitionFromJson(jsonOptions: any, basePath: string, configFileName?: string): {
-        options: TypeAcquisition;
-        errors: Diagnostic[];
+    function createSolutionBuilder(compilerHost: CompilerHost, buildHost: BuildHost, rootNames: ReadonlyArray<string>, defaultOptions: BuildOptions, system?: System): {
+        buildAllProjects: () => number;
+        getUpToDateStatus: (project: ParsedCommandLine | undefined) => UpToDateStatus;
+        getUpToDateStatusOfFile: (configFileName: ResolvedConfigFileName) => UpToDateStatus;
+        cleanAllProjects: () => ExitStatus.Success | ExitStatus.DiagnosticsPresent_OutputsSkipped;
+        resetBuildContext: (opts?: BuildOptions) => void;
+        getBuildGraph: (configFileNames: ReadonlyArray<string>) => DependencyGraph | undefined;
+        invalidateProject: (configFileName: string) => void;
+        buildInvalidatedProjects: () => void;
+        buildDependentInvalidatedProjects: () => void;
+        resolveProjectName: (name: string) => ResolvedConfigFileName | undefined;
+        startWatching: () => void;
     };
 }
 declare namespace ts {
@@ -5346,5 +5526,5 @@ declare namespace ts {
      */
     function transform<T extends Node>(source: T | T[], transformers: TransformerFactory<T>[], compilerOptions?: CompilerOptions): TransformationResult<T>;
 }
-
-export = ts;
\ No newline at end of file
+//# sourceMappingURL=typescriptservices.d.ts.map
+export = ts
\ No newline at end of file
diff --git a/lib/typescriptServices.d.ts b/lib/typescriptServices.d.ts
index 52831570333..6611fbcd0df 100644
--- a/lib/typescriptServices.d.ts
+++ b/lib/typescriptServices.d.ts
@@ -13,6 +13,12 @@ See the Apache Version 2.0 License for specific language governing permissions
 and limitations under the License.
 ***************************************************************************** */
 
+
+declare namespace ts {
+    const versionMajorMinor = "3.0";
+    /** The version of the TypeScript compiler release */
+    const version: string;
+}
 declare namespace ts {
     /**
      * Type of objects whose values are all of the same type.
@@ -22,6 +28,9 @@ declare namespace ts {
     interface MapLike<T> {
         [index: string]: T;
     }
+    interface SortedArray<T> extends Array<T> {
+        " __sortedArrayBrand": any;
+    }
     /** ES6 Map interface, only read methods included. */
     interface ReadonlyMap<T> {
         get(key: string): T | undefined;
@@ -52,6 +61,8 @@ declare namespace ts {
     interface Push<T> {
         push(...values: T[]): void;
     }
+}
+declare namespace ts {
     type Path = string & {
         __pathBrand: any;
     };
@@ -2071,7 +2082,7 @@ declare namespace ts {
         AliasExcludes = 2097152,
         ModuleMember = 2623475,
         ExportHasLocal = 944,
-        HasExports = 1952,
+        HasExports = 1955,
         HasMembers = 6240,
         BlockScoped = 418,
         PropertyOrAccessor = 98308,
@@ -2906,9 +2917,6 @@ declare namespace ts {
         span: TextSpan;
         newLength: number;
     }
-    interface SortedArray<T> extends Array<T> {
-        " __sortedArrayBrand": any;
-    }
     interface SyntaxList extends Node {
         _children: Node[];
     }
@@ -2978,15 +2986,6 @@ declare namespace ts {
         IndexSignatureParameters = 4432
     }
 }
-declare namespace ts {
-    const versionMajorMinor = "3.0";
-    /** The version of the TypeScript compiler release */
-    const version: string;
-}
-declare namespace ts {
-    function isExternalModuleNameRelative(moduleName: string): boolean;
-    function sortAndDeduplicateDiagnostics<T extends Diagnostic>(diagnostics: ReadonlyArray<T>): T[];
-}
 declare function setTimeout(handler: (...args: any[]) => void, timeout: number): any;
 declare function clearTimeout(handle: any): void;
 declare namespace ts {
@@ -3099,6 +3098,11 @@ declare namespace ts {
     function isIdentifierPart(ch: number, languageVersion: ScriptTarget | undefined): boolean;
     function createScanner(languageVersion: ScriptTarget, skipTrivia: boolean, languageVariant?: LanguageVariant, textInitial?: string, onError?: ErrorCallback, start?: number, length?: number): Scanner;
 }
+/** Non-internal stuff goes here */
+declare namespace ts {
+    function isExternalModuleNameRelative(moduleName: string): boolean;
+    function sortAndDeduplicateDiagnostics<T extends Diagnostic>(diagnostics: ReadonlyArray<T>): T[];
+}
 declare namespace ts {
     function getDefaultLibFileName(options: CompilerOptions): string;
     function textSpanEnd(span: TextSpan): number;
@@ -3484,6 +3488,79 @@ declare namespace ts {
     function isExternalModule(file: SourceFile): boolean;
     function updateSourceFile(sourceFile: SourceFile, newText: string, textChangeRange: TextChangeRange, aggressiveChecks?: boolean): SourceFile;
 }
+declare namespace ts {
+    function parseCommandLine(commandLine: ReadonlyArray<string>, readFile?: (path: string) => string | undefined): ParsedCommandLine;
+    type DiagnosticReporter = (diagnostic: Diagnostic) => void;
+    /**
+     * Reports config file diagnostics
+     */
+    interface ConfigFileDiagnosticsReporter {
+        /**
+         * Reports unrecoverable error when parsing config file
+         */
+        onUnRecoverableConfigFileDiagnostic: DiagnosticReporter;
+    }
+    /**
+     * Interface extending ParseConfigHost to support ParseConfigFile that reads config file and reports errors
+     */
+    interface ParseConfigFileHost extends ParseConfigHost, ConfigFileDiagnosticsReporter {
+        getCurrentDirectory(): string;
+    }
+    /**
+     * Reads the config file, reports errors if any and exits if the config file cannot be found
+     */
+    function getParsedCommandLineOfConfigFile(configFileName: string, optionsToExtend: CompilerOptions, host: ParseConfigFileHost): ParsedCommandLine | undefined;
+    /**
+     * Read tsconfig.json file
+     * @param fileName The path to the config file
+     */
+    function readConfigFile(fileName: string, readFile: (path: string) => string | undefined): {
+        config?: any;
+        error?: Diagnostic;
+    };
+    /**
+     * Parse the text of the tsconfig.json file
+     * @param fileName The path to the config file
+     * @param jsonText The text of the config file
+     */
+    function parseConfigFileTextToJson(fileName: string, jsonText: string): {
+        config?: any;
+        error?: Diagnostic;
+    };
+    /**
+     * Read tsconfig.json file
+     * @param fileName The path to the config file
+     */
+    function readJsonConfigFile(fileName: string, readFile: (path: string) => string | undefined): TsConfigSourceFile;
+    /**
+     * Convert the json syntax tree into the json value
+     */
+    function convertToObject(sourceFile: JsonSourceFile, errors: Push<Diagnostic>): any;
+    /**
+     * Parse the contents of a config file (tsconfig.json).
+     * @param json The contents of the config file to parse
+     * @param host Instance of ParseConfigHost used to enumerate files in folder.
+     * @param basePath A root directory to resolve relative path entries in the config
+     *    file to. e.g. outDir
+     */
+    function parseJsonConfigFileContent(json: any, host: ParseConfigHost, basePath: string, existingOptions?: CompilerOptions, configFileName?: string, resolutionStack?: Path[], extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): ParsedCommandLine;
+    /**
+     * Parse the contents of a config file (tsconfig.json).
+     * @param jsonNode The contents of the config file to parse
+     * @param host Instance of ParseConfigHost used to enumerate files in folder.
+     * @param basePath A root directory to resolve relative path entries in the config
+     *    file to. e.g. outDir
+     */
+    function parseJsonSourceFileConfigFileContent(sourceFile: TsConfigSourceFile, host: ParseConfigHost, basePath: string, existingOptions?: CompilerOptions, configFileName?: string, resolutionStack?: Path[], extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): ParsedCommandLine;
+    function convertCompilerOptionsFromJson(jsonOptions: any, basePath: string, configFileName?: string): {
+        options: CompilerOptions;
+        errors: Diagnostic[];
+    };
+    function convertTypeAcquisitionFromJson(jsonOptions: any, basePath: string, configFileName?: string): {
+        options: TypeAcquisition;
+        errors: Diagnostic[];
+    };
+}
 declare namespace ts {
     function getEffectiveTypeRoots(options: CompilerOptions, host: GetEffectiveTypeRootsHost): string[] | undefined;
     /**
@@ -4311,76 +4388,179 @@ declare namespace ts {
     function createWatchProgram<T extends BuilderProgram>(host: WatchCompilerHostOfConfigFile<T>): WatchOfConfigFile<T>;
 }
 declare namespace ts {
-    function parseCommandLine(commandLine: ReadonlyArray<string>, readFile?: (path: string) => string | undefined): ParsedCommandLine;
-    type DiagnosticReporter = (diagnostic: Diagnostic) => void;
     /**
-     * Reports config file diagnostics
+     * Branded string for keeping track of when we've turned an ambiguous path
+     * specified like "./blah" to an absolute path to an actual
+     * tsconfig file, e.g. "/root/blah/tsconfig.json"
      */
-    interface ConfigFileDiagnosticsReporter {
+    type ResolvedConfigFileName = string & {
+        _isResolvedConfigFileName: never;
+    };
+    interface BuildHost {
+        verbose(diag: DiagnosticMessage, ...args: string[]): void;
+        error(diag: DiagnosticMessage, ...args: string[]): void;
+        errorDiagnostic(diag: Diagnostic): void;
+        message(diag: DiagnosticMessage, ...args: string[]): void;
+    }
+    /**
+     * A BuildContext tracks what's going on during the course of a build.
+     *
+     * Callers may invoke any number of build requests within the same context;
+     * until the context is reset, each project will only be built at most once.
+     *
+     * Example: In a standard setup where project B depends on project A, and both are out of date,
+     * a failed build of A will result in A remaining out of date. When we try to build
+     * B, we should immediately bail instead of recomputing A's up-to-date status again.
+     *
+     * This also matters for performing fast (i.e. fake) downstream builds of projects
+     * when their upstream .d.ts files haven't changed content (but have newer timestamps)
+     */
+    interface BuildContext {
+        options: BuildOptions;
         /**
-         * Reports unrecoverable error when parsing config file
+         * Map from output file name to its pre-build timestamp
          */
-        onUnRecoverableConfigFileDiagnostic: DiagnosticReporter;
+        unchangedOutputs: FileMap<Date>;
+        /**
+         * Map from config file name to up-to-date status
+         */
+        projectStatus: FileMap<UpToDateStatus>;
+        invalidatedProjects: FileMap<true>;
+        queuedProjects: FileMap<true>;
+        missingRoots: Map<true>;
     }
-    /**
-     * Interface extending ParseConfigHost to support ParseConfigFile that reads config file and reports errors
-     */
-    interface ParseConfigFileHost extends ParseConfigHost, ConfigFileDiagnosticsReporter {
-        getCurrentDirectory(): string;
+    type Mapper = ReturnType<typeof createDependencyMapper>;
+    interface DependencyGraph {
+        buildQueue: ResolvedConfigFileName[];
+        dependencyMap: Mapper;
     }
-    /**
-     * Reads the config file, reports errors if any and exits if the config file cannot be found
-     */
-    function getParsedCommandLineOfConfigFile(configFileName: string, optionsToExtend: CompilerOptions, host: ParseConfigFileHost): ParsedCommandLine | undefined;
-    /**
-     * Read tsconfig.json file
-     * @param fileName The path to the config file
-     */
-    function readConfigFile(fileName: string, readFile: (path: string) => string | undefined): {
-        config?: any;
-        error?: Diagnostic;
+    interface BuildOptions {
+        dry: boolean;
+        force: boolean;
+        verbose: boolean;
+    }
+    enum UpToDateStatusType {
+        Unbuildable = 0,
+        UpToDate = 1,
+        /**
+         * The project appears out of date because its upstream inputs are newer than its outputs,
+         * but all of its outputs are actually newer than the previous identical outputs of its (.d.ts) inputs.
+         * This means we can Pseudo-build (just touch timestamps), as if we had actually built this project.
+         */
+        UpToDateWithUpstreamTypes = 2,
+        OutputMissing = 3,
+        OutOfDateWithSelf = 4,
+        OutOfDateWithUpstream = 5,
+        UpstreamOutOfDate = 6,
+        UpstreamBlocked = 7,
+        /**
+         * Projects with no outputs (i.e. "solution" files)
+         */
+        ContainerOnly = 8
+    }
+    type UpToDateStatus = Status.Unbuildable | Status.UpToDate | Status.OutputMissing | Status.OutOfDateWithSelf | Status.OutOfDateWithUpstream | Status.UpstreamOutOfDate | Status.UpstreamBlocked | Status.ContainerOnly;
+    namespace Status {
+        /**
+         * The project can't be built at all in its current state. For example,
+         * its config file cannot be parsed, or it has a syntax error or missing file
+         */
+        interface Unbuildable {
+            type: UpToDateStatusType.Unbuildable;
+            reason: string;
+        }
+        /**
+         * This project doesn't have any outputs, so "is it up to date" is a meaningless question.
+         */
+        interface ContainerOnly {
+            type: UpToDateStatusType.ContainerOnly;
+        }
+        /**
+         * The project is up to date with respect to its inputs.
+         * We track what the newest input file is.
+         */
+        interface UpToDate {
+            type: UpToDateStatusType.UpToDate | UpToDateStatusType.UpToDateWithUpstreamTypes;
+            newestInputFileTime: Date;
+            newestInputFileName: string;
+            newestDeclarationFileContentChangedTime: Date;
+            newestOutputFileTime: Date;
+            newestOutputFileName: string;
+            oldestOutputFileName: string;
+        }
+        /**
+         * One or more of the outputs of the project does not exist.
+         */
+        interface OutputMissing {
+            type: UpToDateStatusType.OutputMissing;
+            /**
+             * The name of the first output file that didn't exist
+             */
+            missingOutputFileName: string;
+        }
+        /**
+         * One or more of the project's outputs is older than its newest input.
+         */
+        interface OutOfDateWithSelf {
+            type: UpToDateStatusType.OutOfDateWithSelf;
+            outOfDateOutputFileName: string;
+            newerInputFileName: string;
+        }
+        /**
+         * This project depends on an out-of-date project, so shouldn't be built yet
+         */
+        interface UpstreamOutOfDate {
+            type: UpToDateStatusType.UpstreamOutOfDate;
+            upstreamProjectName: string;
+        }
+        /**
+         * This project depends an upstream project with build errors
+         */
+        interface UpstreamBlocked {
+            type: UpToDateStatusType.UpstreamBlocked;
+            upstreamProjectName: string;
+        }
+        /**
+         * One or more of the project's outputs is older than the newest output of
+         * an upstream project.
+         */
+        interface OutOfDateWithUpstream {
+            type: UpToDateStatusType.OutOfDateWithUpstream;
+            outOfDateOutputFileName: string;
+            newerProjectName: string;
+        }
+    }
+    interface FileMap<T> {
+        setValue(fileName: string, value: T): void;
+        getValue(fileName: string): T | never;
+        getValueOrUndefined(fileName: string): T | undefined;
+        hasKey(fileName: string): boolean;
+        removeKey(fileName: string): void;
+        getKeys(): string[];
+    }
+    function createDependencyMapper(): {
+        addReference: (childConfigFileName: ResolvedConfigFileName, parentConfigFileName: ResolvedConfigFileName) => void;
+        getReferencesTo: (parentConfigFileName: ResolvedConfigFileName) => ResolvedConfigFileName[];
+        getReferencesOf: (childConfigFileName: ResolvedConfigFileName) => ResolvedConfigFileName[];
+        getKeys: () => ReadonlyArray<ResolvedConfigFileName>;
     };
+    function createBuildContext(options: BuildOptions): BuildContext;
+    function performBuild(args: string[], compilerHost: CompilerHost, buildHost: BuildHost, system?: System): number | undefined;
     /**
-     * Parse the text of the tsconfig.json file
-     * @param fileName The path to the config file
-     * @param jsonText The text of the config file
+     * A SolutionBuilder has an immutable set of rootNames that are the "entry point" projects, but
+     * can dynamically add/remove other projects based on changes on the rootNames' references
      */
-    function parseConfigFileTextToJson(fileName: string, jsonText: string): {
-        config?: any;
-        error?: Diagnostic;
-    };
-    /**
-     * Read tsconfig.json file
-     * @param fileName The path to the config file
-     */
-    function readJsonConfigFile(fileName: string, readFile: (path: string) => string | undefined): TsConfigSourceFile;
-    /**
-     * Convert the json syntax tree into the json value
-     */
-    function convertToObject(sourceFile: JsonSourceFile, errors: Push<Diagnostic>): any;
-    /**
-     * Parse the contents of a config file (tsconfig.json).
-     * @param json The contents of the config file to parse
-     * @param host Instance of ParseConfigHost used to enumerate files in folder.
-     * @param basePath A root directory to resolve relative path entries in the config
-     *    file to. e.g. outDir
-     */
-    function parseJsonConfigFileContent(json: any, host: ParseConfigHost, basePath: string, existingOptions?: CompilerOptions, configFileName?: string, resolutionStack?: Path[], extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): ParsedCommandLine;
-    /**
-     * Parse the contents of a config file (tsconfig.json).
-     * @param jsonNode The contents of the config file to parse
-     * @param host Instance of ParseConfigHost used to enumerate files in folder.
-     * @param basePath A root directory to resolve relative path entries in the config
-     *    file to. e.g. outDir
-     */
-    function parseJsonSourceFileConfigFileContent(sourceFile: TsConfigSourceFile, host: ParseConfigHost, basePath: string, existingOptions?: CompilerOptions, configFileName?: string, resolutionStack?: Path[], extraFileExtensions?: ReadonlyArray<FileExtensionInfo>): ParsedCommandLine;
-    function convertCompilerOptionsFromJson(jsonOptions: any, basePath: string, configFileName?: string): {
-        options: CompilerOptions;
-        errors: Diagnostic[];
-    };
-    function convertTypeAcquisitionFromJson(jsonOptions: any, basePath: string, configFileName?: string): {
-        options: TypeAcquisition;
-        errors: Diagnostic[];
+    function createSolutionBuilder(compilerHost: CompilerHost, buildHost: BuildHost, rootNames: ReadonlyArray<string>, defaultOptions: BuildOptions, system?: System): {
+        buildAllProjects: () => number;
+        getUpToDateStatus: (project: ParsedCommandLine | undefined) => UpToDateStatus;
+        getUpToDateStatusOfFile: (configFileName: ResolvedConfigFileName) => UpToDateStatus;
+        cleanAllProjects: () => ExitStatus.Success | ExitStatus.DiagnosticsPresent_OutputsSkipped;
+        resetBuildContext: (opts?: BuildOptions) => void;
+        getBuildGraph: (configFileNames: ReadonlyArray<string>) => DependencyGraph | undefined;
+        invalidateProject: (configFileName: string) => void;
+        buildInvalidatedProjects: () => void;
+        buildDependentInvalidatedProjects: () => void;
+        resolveProjectName: (name: string) => ResolvedConfigFileName | undefined;
+        startWatching: () => void;
     };
 }
 declare namespace ts {
@@ -5346,3 +5526,4 @@ declare namespace ts {
      */
     function transform<T extends Node>(source: T | T[], transformers: TransformerFactory<T>[], compilerOptions?: CompilerOptions): TransformationResult<T>;
 }
+//# sourceMappingURL=typescriptservices.d.ts.map
\ No newline at end of file
diff --git a/lib/typingsInstaller.js b/lib/typingsInstaller.js
index 33830d8df54..ca368f2fba5 100644
--- a/lib/typingsInstaller.js
+++ b/lib/typingsInstaller.js
@@ -1,3 +1,19 @@
+/*! *****************************************************************************
+Copyright (c) Microsoft Corporation. All rights reserved. 
+Licensed under the Apache License, Version 2.0 (the "License"); you may not use
+this file except in compliance with the License. You may obtain a copy of the
+License at http://www.apache.org/licenses/LICENSE-2.0  
+ 
+THIS CODE IS PROVIDED ON AN *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED
+WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE, 
+MERCHANTABLITY OR NON-INFRINGEMENT. 
+ 
+See the Apache Version 2.0 License for specific language governing permissions
+and limitations under the License.
+***************************************************************************** */
+
+
 "use strict";
 var __extends = (this && this.__extends) || (function () {
     var extendStatics = Object.setPrototypeOf ||
@@ -18,99 +34,18 @@ var __assign = (this && this.__assign) || Object.assign || function(t) {
     return t;
 };
 "use strict";
-/*@internal*/
-var ts;
-(function (ts) {
-    /** Gets a timestamp with (at least) ms resolution */
-    ts.timestamp = typeof performance !== "undefined" && performance.now ? function () { return performance.now(); } : Date.now ? Date.now : function () { return +(new Date()); };
-})(ts || (ts = {}));
-/*@internal*/
-/** Performance measurements for the compiler. */
-(function (ts) {
-    var performance;
-    (function (performance) {
-        // NOTE: cannot use ts.noop as core.ts loads after this
-        var profilerEvent = typeof onProfilerEvent === "function" && onProfilerEvent.profiler === true ? onProfilerEvent : function () { };
-        var enabled = false;
-        var profilerStart = 0;
-        var counts;
-        var marks;
-        var measures;
-        /**
-         * Marks a performance event.
-         *
-         * @param markName The name of the mark.
-         */
-        function mark(markName) {
-            if (enabled) {
-                marks.set(markName, ts.timestamp());
-                counts.set(markName, (counts.get(markName) || 0) + 1);
-                profilerEvent(markName);
-            }
-        }
-        performance.mark = mark;
-        /**
-         * Adds a performance measurement with the specified name.
-         *
-         * @param measureName The name of the performance measurement.
-         * @param startMarkName The name of the starting mark. If not supplied, the point at which the
-         *      profiler was enabled is used.
-         * @param endMarkName The name of the ending mark. If not supplied, the current timestamp is
-         *      used.
-         */
-        function measure(measureName, startMarkName, endMarkName) {
-            if (enabled) {
-                var end = endMarkName && marks.get(endMarkName) || ts.timestamp();
-                var start = startMarkName && marks.get(startMarkName) || profilerStart;
-                measures.set(measureName, (measures.get(measureName) || 0) + (end - start));
-            }
-        }
-        performance.measure = measure;
-        /**
-         * Gets the number of times a marker was encountered.
-         *
-         * @param markName The name of the mark.
-         */
-        function getCount(markName) {
-            return counts && counts.get(markName) || 0;
-        }
-        performance.getCount = getCount;
-        /**
-         * Gets the total duration of all measurements with the supplied name.
-         *
-         * @param measureName The name of the measure whose durations should be accumulated.
-         */
-        function getDuration(measureName) {
-            return measures && measures.get(measureName) || 0;
-        }
-        performance.getDuration = getDuration;
-        /**
-         * Iterate over each measure, performing some action
-         *
-         * @param cb The action to perform for each measure
-         */
-        function forEachMeasure(cb) {
-            measures.forEach(function (measure, key) {
-                cb(key, measure);
-            });
-        }
-        performance.forEachMeasure = forEachMeasure;
-        /** Enables (and resets) performance measurements for the compiler. */
-        function enable() {
-            counts = ts.createMap();
-            marks = ts.createMap();
-            measures = ts.createMap();
-            enabled = true;
-            profilerStart = ts.timestamp();
-        }
-        performance.enable = enable;
-        /** Disables performance measurements for the compiler. */
-        function disable() {
-            enabled = false;
-        }
-        performance.disable = disable;
-    })(performance = ts.performance || (ts.performance = {}));
-})(ts || (ts = {}));
+var __assign = (this && this.__assign) || Object.assign || function(t) {
+    for (var s, i = 1, n = arguments.length; i < n; i++) {
+        s = arguments[i];
+        for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
+            t[p] = s[p];
+    }
+    return t;
+};
+var __makeTemplateObject = (this && this.__makeTemplateObject) || function (cooked, raw) {
+    if (Object.defineProperty) { Object.defineProperty(cooked, "raw", { value: raw }); } else { cooked.raw = raw; }
+    return cooked;
+};
 var ts;
 (function (ts) {
     // WARNING: The script `configureNightly.ts` uses a regexp to parse out these values.
@@ -119,14 +54,17 @@ var ts;
     /** The version of the TypeScript compiler release */
     ts.version = ts.versionMajorMinor + ".0-dev";
 })(ts || (ts = {}));
-/* @internal */
 (function (ts) {
+    /* @internal */
     var Comparison;
     (function (Comparison) {
         Comparison[Comparison["LessThan"] = -1] = "LessThan";
         Comparison[Comparison["EqualTo"] = 0] = "EqualTo";
         Comparison[Comparison["GreaterThan"] = 1] = "GreaterThan";
     })(Comparison = ts.Comparison || (ts.Comparison = {}));
+})(ts || (ts = {}));
+/* @internal */
+(function (ts) {
     /** Create a MapLike with good performance. */
     function createDictionaryObject() {
         var map = Object.create(/*prototype*/ null); // tslint:disable-line:no-null-keyword
@@ -1988,16 +1926,99 @@ var ts;
     }
     ts.enumerateInsertsAndDeletes = enumerateInsertsAndDeletes;
 })(ts || (ts = {}));
-//# sourceMappingURL=core.js.map
-"use strict";
-var __assign = (this && this.__assign) || Object.assign || function(t) {
-    for (var s, i = 1, n = arguments.length; i < n; i++) {
-        s = arguments[i];
-        for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))
-            t[p] = s[p];
-    }
-    return t;
-};
+/*@internal*/
+var ts;
+(function (ts) {
+    /** Gets a timestamp with (at least) ms resolution */
+    ts.timestamp = typeof performance !== "undefined" && performance.now ? function () { return performance.now(); } : Date.now ? Date.now : function () { return +(new Date()); };
+})(ts || (ts = {}));
+/*@internal*/
+/** Performance measurements for the compiler. */
+(function (ts) {
+    var performance;
+    (function (performance) {
+        // NOTE: cannot use ts.noop as core.ts loads after this
+        var profilerEvent = typeof onProfilerEvent === "function" && onProfilerEvent.profiler === true ? onProfilerEvent : function () { };
+        var enabled = false;
+        var profilerStart = 0;
+        var counts;
+        var marks;
+        var measures;
+        /**
+         * Marks a performance event.
+         *
+         * @param markName The name of the mark.
+         */
+        function mark(markName) {
+            if (enabled) {
+                marks.set(markName, ts.timestamp());
+                counts.set(markName, (counts.get(markName) || 0) + 1);
+                profilerEvent(markName);
+            }
+        }
+        performance.mark = mark;
+        /**
+         * Adds a performance measurement with the specified name.
+         *
+         * @param measureName The name of the performance measurement.
+         * @param startMarkName The name of the starting mark. If not supplied, the point at which the
+         *      profiler was enabled is used.
+         * @param endMarkName The name of the ending mark. If not supplied, the current timestamp is
+         *      used.
+         */
+        function measure(measureName, startMarkName, endMarkName) {
+            if (enabled) {
+                var end = endMarkName && marks.get(endMarkName) || ts.timestamp();
+                var start = startMarkName && marks.get(startMarkName) || profilerStart;
+                measures.set(measureName, (measures.get(measureName) || 0) + (end - start));
+            }
+        }
+        performance.measure = measure;
+        /**
+         * Gets the number of times a marker was encountered.
+         *
+         * @param markName The name of the mark.
+         */
+        function getCount(markName) {
+            return counts && counts.get(markName) || 0;
+        }
+        performance.getCount = getCount;
+        /**
+         * Gets the total duration of all measurements with the supplied name.
+         *
+         * @param measureName The name of the measure whose durations should be accumulated.
+         */
+        function getDuration(measureName) {
+            return measures && measures.get(measureName) || 0;
+        }
+        performance.getDuration = getDuration;
+        /**
+         * Iterate over each measure, performing some action
+         *
+         * @param cb The action to perform for each measure
+         */
+        function forEachMeasure(cb) {
+            measures.forEach(function (measure, key) {
+                cb(key, measure);
+            });
+        }
+        performance.forEachMeasure = forEachMeasure;
+        /** Enables (and resets) performance measurements for the compiler. */
+        function enable() {
+            counts = ts.createMap();
+            marks = ts.createMap();
+            measures = ts.createMap();
+            enabled = true;
+            profilerStart = ts.timestamp();
+        }
+        performance.enable = enable;
+        /** Disables performance measurements for the compiler. */
+        function disable() {
+            enabled = false;
+        }
+        performance.disable = disable;
+    })(performance = ts.performance || (ts.performance = {}));
+})(ts || (ts = {}));
 var ts;
 (function (ts) {
     // token > SyntaxKind.Identifier => token is a keyword
@@ -4274,8 +4295,8 @@ var ts;
                     var entries = _fs.readdirSync(path || ".").sort();
                     var files = [];
                     var directories = [];
-                    for (var _i = 0, entries_1 = entries; _i < entries_1.length; _i++) {
-                        var entry = entries_1[_i];
+                    for (var _i = 0, entries_2 = entries; _i < entries_2.length; _i++) {
+                        var entry = entries_2[_i];
                         // This is necessary because on some file system node fails to exclude
                         // "." and "..". See https://github.com/nodejs/node/issues/4002
                         if (entry === "." || entry === "..") {
@@ -4455,7 +4476,7 @@ var ts;
     }
 })(ts || (ts = {}));
 // <auto-generated />
-// generated from './diagnosticInformationMap.generated.ts' by 'src\parser'
+// generated from './diagnosticInformationMap.generated.ts' by 'src\compiler'
 /* @internal */
 var ts;
 (function (ts) {
@@ -7449,11 +7470,6 @@ var ts;
 /** Non-internal stuff goes here */
 var ts;
 (function (ts) {
-    ts.emptyArray = [];
-    function closeFileWatcher(watcher) {
-        watcher.close();
-    }
-    ts.closeFileWatcher = closeFileWatcher;
     function isExternalModuleNameRelative(moduleName) {
         // TypeScript 1.0 spec (April 2014): 11.2.1
         // An external module name is "relative" if the first term is "." or "..".
@@ -7465,20 +7481,10 @@ var ts;
         return ts.sortAndDeduplicate(diagnostics, ts.compareDiagnostics);
     }
     ts.sortAndDeduplicateDiagnostics = sortAndDeduplicateDiagnostics;
-    function toPath(fileName, basePath, getCanonicalFileName) {
-        var nonCanonicalizedPath = ts.isRootedDiskPath(fileName)
-            ? ts.normalizePath(fileName)
-            : ts.getNormalizedAbsolutePath(fileName, basePath);
-        return getCanonicalFileName(nonCanonicalizedPath);
-    }
-    ts.toPath = toPath;
-    function hasEntries(map) {
-        return !!map && !!map.size;
-    }
-    ts.hasEntries = hasEntries;
 })(ts || (ts = {}));
 /* @internal */
 (function (ts) {
+    ts.emptyArray = [];
     ts.resolvingEmptyArray = [];
     ts.emptyMap = ts.createMap();
     ts.emptyUnderscoreEscapedMap = ts.emptyMap;
@@ -7501,6 +7507,10 @@ var ts;
         return new ts.MapCtr();
     }
     ts.createUnderscoreEscapedMap = createUnderscoreEscapedMap;
+    function hasEntries(map) {
+        return !!map && !!map.size;
+    }
+    ts.hasEntries = hasEntries;
     function createSymbolTable(symbols) {
         var result = ts.createMap();
         if (symbols) {
@@ -7547,6 +7557,13 @@ var ts;
             reportPrivateInBaseOfClassExpression: ts.noop,
         };
     }
+    function toPath(fileName, basePath, getCanonicalFileName) {
+        var nonCanonicalizedPath = ts.isRootedDiskPath(fileName)
+            ? ts.normalizePath(fileName)
+            : ts.getNormalizedAbsolutePath(fileName, basePath);
+        return getCanonicalFileName(nonCanonicalizedPath);
+    }
+    ts.toPath = toPath;
     function changesAffectModuleResolution(oldOptions, newOptions) {
         return !oldOptions ||
             (oldOptions.module !== newOptions.module) ||
@@ -10376,7 +10393,7 @@ var ts;
      */
     function getExternalModuleNameFromPath(host, fileName, referencePath) {
         var getCanonicalFileName = function (f) { return host.getCanonicalFileName(f); };
-        var dir = ts.toPath(referencePath ? ts.getDirectoryPath(referencePath) : host.getCommonSourceDirectory(), host.getCurrentDirectory(), getCanonicalFileName);
+        var dir = toPath(referencePath ? ts.getDirectoryPath(referencePath) : host.getCommonSourceDirectory(), host.getCurrentDirectory(), getCanonicalFileName);
         var filePath = ts.getNormalizedAbsolutePath(fileName, host.getCurrentDirectory());
         var relativePath = ts.getRelativePathToDirectoryOrUrl(dir, filePath, dir, getCanonicalFileName, /*isAbsolutePathAnUrl*/ false);
         var extensionless = ts.removeFileExtension(relativePath);
@@ -11284,6 +11301,10 @@ var ts;
         return options.watch && options.hasOwnProperty("watch");
     }
     ts.isWatchSet = isWatchSet;
+    function closeFileWatcher(watcher) {
+        watcher.close();
+    }
+    ts.closeFileWatcher = closeFileWatcher;
     function getCheckFlags(symbol) {
         return symbol.flags & 33554432 /* Transient */ ? symbol.checkFlags : 0;
     }
@@ -13706,6 +13727,9 @@ var ts;
         return node.kind === 9 /* StringLiteral */ || node.kind === 13 /* NoSubstitutionTemplateLiteral */;
     }
     ts.isStringLiteralLike = isStringLiteralLike;
+})(ts || (ts = {}));
+/* @internal */
+(function (ts) {
     /** @internal */
     function isNamedImportsOrExports(node) {
         return node.kind === 247 /* NamedImports */ || node.kind === 251 /* NamedExports */;
@@ -13722,7 +13746,7 @@ var ts;
     }
     function Type(checker, flags) {
         this.flags = flags;
-        if (Debug.isDebugging) {
+        if (ts.Debug.isDebugging) {
             this.checker = checker;
         }
     }
@@ -13753,9 +13777,10 @@ var ts;
         getSignatureConstructor: function () { return Signature; },
         getSourceMapSourceConstructor: function () { return SourceMapSource; },
     };
+    /* @internal */
     function formatStringFromArgs(text, args, baseIndex) {
         if (baseIndex === void 0) { baseIndex = 0; }
-        return text.replace(/{(\d+)}/g, function (_match, index) { return Debug.assertDefined(args[+index + baseIndex]); });
+        return text.replace(/{(\d+)}/g, function (_match, index) { return ts.Debug.assertDefined(args[+index + baseIndex]); });
     }
     ts.formatStringFromArgs = formatStringFromArgs;
     function getLocaleSpecificMessage(message) {
@@ -13763,11 +13788,11 @@ var ts;
     }
     ts.getLocaleSpecificMessage = getLocaleSpecificMessage;
     function createFileDiagnostic(file, start, length, message) {
-        Debug.assertGreaterThanOrEqual(start, 0);
-        Debug.assertGreaterThanOrEqual(length, 0);
+        ts.Debug.assertGreaterThanOrEqual(start, 0);
+        ts.Debug.assertGreaterThanOrEqual(length, 0);
         if (file) {
-            Debug.assertLessThanOrEqual(start, file.text.length);
-            Debug.assertLessThanOrEqual(start + length, file.text.length);
+            ts.Debug.assertLessThanOrEqual(start, file.text.length);
+            ts.Debug.assertLessThanOrEqual(start + length, file.text.length);
         }
         var text = getLocaleSpecificMessage(message);
         if (arguments.length > 4) {
@@ -13809,6 +13834,7 @@ var ts;
         };
     }
     ts.createCompilerDiagnostic = createCompilerDiagnostic;
+    /* @internal */
     function createCompilerDiagnosticFromMessageChain(chain) {
         return {
             file: undefined,
@@ -13845,6 +13871,7 @@ var ts;
     function getDiagnosticFilePath(diagnostic) {
         return diagnostic.file ? diagnostic.file.path : undefined;
     }
+    /* @internal */
     function compareDiagnostics(d1, d2) {
         return ts.compareStringsCaseSensitive(getDiagnosticFilePath(d1), getDiagnosticFilePath(d2)) ||
             ts.compareValues(d1.start, d2.start) ||
@@ -14059,7 +14086,7 @@ var ts;
     ts.getRootLength = getRootLength;
     // TODO(rbuckton): replace references with `resolvePath`
     function normalizePath(path) {
-        return resolvePath(path);
+        return ts.resolvePath(path);
     }
     ts.normalizePath = normalizePath;
     function normalizePathAndParts(path) {
@@ -14067,7 +14094,7 @@ var ts;
         var _a = reducePathComponents(getPathComponents(path)), root = _a[0], parts = _a.slice(1);
         if (parts.length) {
             var joinedParts = root + parts.join(ts.directorySeparator);
-            return { path: hasTrailingDirectorySeparator(path) ? ensureTrailingDirectorySeparator(joinedParts) : joinedParts, parts: parts };
+            return { path: ts.hasTrailingDirectorySeparator(path) ? ts.ensureTrailingDirectorySeparator(joinedParts) : joinedParts, parts: parts };
         }
         else {
             return { path: root, parts: parts };
@@ -14082,7 +14109,7 @@ var ts;
             return path;
         // return the leading portion of the path up to the last (non-terminal) directory separator
         // but not including any trailing directory separator.
-        path = removeTrailingDirectorySeparator(path);
+        path = ts.removeTrailingDirectorySeparator(path);
         return path.slice(0, Math.max(rootLength, path.lastIndexOf(ts.directorySeparator)));
     }
     ts.getDirectoryPath = getDirectoryPath;
@@ -14110,10 +14137,11 @@ var ts;
         return rootLength > 0 && rootLength === path.length;
     }
     ts.isDiskPathRoot = isDiskPathRoot;
+    /* @internal */
     function convertToRelativePath(absoluteOrRelativePath, basePath, getCanonicalFileName) {
         return !isRootedDiskPath(absoluteOrRelativePath)
             ? absoluteOrRelativePath
-            : getRelativePathToDirectoryOrUrl(basePath, absoluteOrRelativePath, basePath, getCanonicalFileName, /*isAbsolutePathAnUrl*/ false);
+            : ts.getRelativePathToDirectoryOrUrl(basePath, absoluteOrRelativePath, basePath, getCanonicalFileName, /*isAbsolutePathAnUrl*/ false);
     }
     ts.convertToRelativePath = convertToRelativePath;
     function pathComponents(path, rootLength) {
@@ -14131,7 +14159,7 @@ var ts;
      */
     function getPathComponents(path, currentDirectory) {
         if (currentDirectory === void 0) { currentDirectory = ""; }
-        path = combinePaths(currentDirectory, path);
+        path = ts.combinePaths(currentDirectory, path);
         var rootLength = getRootLength(path);
         return pathComponents(path, rootLength);
     }
@@ -14186,15 +14214,18 @@ var ts;
     function getPathFromPathComponents(pathComponents) {
         if (pathComponents.length === 0)
             return "";
-        var root = pathComponents[0] && ensureTrailingDirectorySeparator(pathComponents[0]);
+        var root = pathComponents[0] && ts.ensureTrailingDirectorySeparator(pathComponents[0]);
         if (pathComponents.length === 1)
             return root;
         return root + pathComponents.slice(1).join(ts.directorySeparator);
     }
     ts.getPathFromPathComponents = getPathFromPathComponents;
+})(ts || (ts = {}));
+/* @internal */
+(function (ts) {
     function getPathComponentsRelativeTo(from, to, stringEqualityComparer, getCanonicalFileName) {
-        var fromComponents = reducePathComponents(getPathComponents(from));
-        var toComponents = reducePathComponents(getPathComponents(to));
+        var fromComponents = ts.reducePathComponents(ts.getPathComponents(from));
+        var toComponents = ts.reducePathComponents(ts.getPathComponents(to));
         var start;
         for (start = 0; start < fromComponents.length && start < toComponents.length; start++) {
             var fromComponent = getCanonicalFileName(fromComponents[start]);
@@ -14213,26 +14244,27 @@ var ts;
         }
         return [""].concat(relative, components);
     }
+    ts.getPathComponentsRelativeTo = getPathComponentsRelativeTo;
     function getRelativePathFromFile(from, to, getCanonicalFileName) {
-        return ensurePathIsNonModuleName(getRelativePathFromDirectory(getDirectoryPath(from), to, getCanonicalFileName));
+        return ensurePathIsNonModuleName(getRelativePathFromDirectory(ts.getDirectoryPath(from), to, getCanonicalFileName));
     }
     ts.getRelativePathFromFile = getRelativePathFromFile;
     function getRelativePathFromDirectory(fromDirectory, to, getCanonicalFileNameOrIgnoreCase) {
-        Debug.assert((getRootLength(fromDirectory) > 0) === (getRootLength(to) > 0), "Paths must either both be absolute or both be relative");
+        Debug.assert((ts.getRootLength(fromDirectory) > 0) === (ts.getRootLength(to) > 0), "Paths must either both be absolute or both be relative");
         var getCanonicalFileName = typeof getCanonicalFileNameOrIgnoreCase === "function" ? getCanonicalFileNameOrIgnoreCase : ts.identity;
         var ignoreCase = typeof getCanonicalFileNameOrIgnoreCase === "boolean" ? getCanonicalFileNameOrIgnoreCase : false;
         var pathComponents = getPathComponentsRelativeTo(fromDirectory, to, ignoreCase ? ts.equateStringsCaseInsensitive : ts.equateStringsCaseSensitive, getCanonicalFileName);
-        return getPathFromPathComponents(pathComponents);
+        return ts.getPathFromPathComponents(pathComponents);
     }
     ts.getRelativePathFromDirectory = getRelativePathFromDirectory;
     function getRelativePathToDirectoryOrUrl(directoryPathOrUrl, relativeOrAbsolutePath, currentDirectory, getCanonicalFileName, isAbsolutePathAnUrl) {
         var pathComponents = getPathComponentsRelativeTo(resolvePath(currentDirectory, directoryPathOrUrl), resolvePath(currentDirectory, relativeOrAbsolutePath), ts.equateStringsCaseSensitive, getCanonicalFileName);
         var firstComponent = pathComponents[0];
-        if (isAbsolutePathAnUrl && isRootedDiskPath(firstComponent)) {
+        if (isAbsolutePathAnUrl && ts.isRootedDiskPath(firstComponent)) {
             var prefix = firstComponent.charAt(0) === ts.directorySeparator ? "file://" : "file:///";
             pathComponents[0] = prefix + firstComponent;
         }
-        return getPathFromPathComponents(pathComponents);
+        return ts.getPathFromPathComponents(pathComponents);
     }
     ts.getRelativePathToDirectoryOrUrl = getRelativePathToDirectoryOrUrl;
     /**
@@ -14240,19 +14272,19 @@ var ts;
      * with `./` or `../`) so as not to be confused with an unprefixed module name.
      */
     function ensurePathIsNonModuleName(path) {
-        return getRootLength(path) === 0 && !pathIsRelative(path) ? "./" + path : path;
+        return ts.getRootLength(path) === 0 && !ts.pathIsRelative(path) ? "./" + path : path;
     }
     ts.ensurePathIsNonModuleName = ensurePathIsNonModuleName;
     function getBaseFileName(path, extensions, ignoreCase) {
-        path = normalizeSlashes(path);
+        path = ts.normalizeSlashes(path);
         // if the path provided is itself the root, then it has not file name.
-        var rootLength = getRootLength(path);
+        var rootLength = ts.getRootLength(path);
         if (rootLength === path.length)
             return "";
         // return the trailing portion of the path starting after the last (non-terminal) directory
         // separator but not including any trailing directory separator.
         path = removeTrailingDirectorySeparator(path);
-        var name = path.slice(Math.max(getRootLength(path), path.lastIndexOf(ts.directorySeparator) + 1));
+        var name = path.slice(Math.max(ts.getRootLength(path), path.lastIndexOf(ts.directorySeparator) + 1));
         var extension = extensions !== undefined && ignoreCase !== undefined ? getAnyExtensionFromPath(name, extensions, ignoreCase) : undefined;
         return extension ? name.slice(0, name.length - extension.length) : name;
     }
@@ -14266,13 +14298,13 @@ var ts;
             paths[_i - 1] = arguments[_i];
         }
         if (path)
-            path = normalizeSlashes(path);
+            path = ts.normalizeSlashes(path);
         for (var _a = 0, paths_1 = paths; _a < paths_1.length; _a++) {
             var relativePath = paths_1[_a];
             if (!relativePath)
                 continue;
-            relativePath = normalizeSlashes(relativePath);
-            if (!path || getRootLength(relativePath) !== 0) {
+            relativePath = ts.normalizeSlashes(relativePath);
+            if (!path || ts.getRootLength(relativePath) !== 0) {
                 path = relativePath;
             }
             else {
@@ -14291,8 +14323,8 @@ var ts;
         for (var _i = 1; _i < arguments.length; _i++) {
             paths[_i - 1] = arguments[_i];
         }
-        var combined = ts.some(paths) ? combinePaths.apply(void 0, [path].concat(paths)) : normalizeSlashes(path);
-        var normalized = getPathFromPathComponents(reducePathComponents(getPathComponents(combined)));
+        var combined = ts.some(paths) ? combinePaths.apply(void 0, [path].concat(paths)) : ts.normalizeSlashes(path);
+        var normalized = ts.getPathFromPathComponents(ts.reducePathComponents(ts.getPathComponents(combined)));
         return normalized && hasTrailingDirectorySeparator(combined) ? ensureTrailingDirectorySeparator(normalized) : normalized;
     }
     ts.resolvePath = resolvePath;
@@ -14327,8 +14359,8 @@ var ts;
             return -1 /* LessThan */;
         if (b === undefined)
             return 1 /* GreaterThan */;
-        var aComponents = reducePathComponents(getPathComponents(a));
-        var bComponents = reducePathComponents(getPathComponents(b));
+        var aComponents = ts.reducePathComponents(ts.getPathComponents(a));
+        var bComponents = ts.reducePathComponents(ts.getPathComponents(b));
         var sharedLength = Math.min(aComponents.length, bComponents.length);
         for (var i = 0; i < sharedLength; i++) {
             var stringComparer = i === 0 ? ts.compareStringsCaseInsensitive : componentComparer;
@@ -14376,8 +14408,8 @@ var ts;
             return false;
         if (parent === child)
             return true;
-        var parentComponents = reducePathComponents(getPathComponents(parent));
-        var childComponents = reducePathComponents(getPathComponents(child));
+        var parentComponents = ts.reducePathComponents(ts.getPathComponents(parent));
+        var childComponents = ts.reducePathComponents(ts.getPathComponents(child));
         if (childComponents.length < parentComponents.length) {
             return false;
         }
@@ -14480,7 +14512,7 @@ var ts;
         var singleAsteriskRegexFragment = _a.singleAsteriskRegexFragment, doubleAsteriskRegexFragment = _a.doubleAsteriskRegexFragment, replaceWildcardCharacter = _a.replaceWildcardCharacter;
         var subpattern = "";
         var hasWrittenComponent = false;
-        var components = getNormalizedPathComponents(spec, basePath);
+        var components = ts.getNormalizedPathComponents(spec, basePath);
         var lastComponent = ts.last(components);
         if (usage !== "exclude" && lastComponent === "**") {
             return undefined;
@@ -14547,8 +14579,8 @@ var ts;
     }
     /** @param path directory of the tsconfig.json */
     function getFileMatcherPatterns(path, excludes, includes, useCaseSensitiveFileNames, currentDirectory) {
-        path = normalizePath(path);
-        currentDirectory = normalizePath(currentDirectory);
+        path = ts.normalizePath(path);
+        currentDirectory = ts.normalizePath(currentDirectory);
         var absolutePath = combinePaths(currentDirectory, path);
         return {
             includeFilePatterns: ts.map(getRegularExpressionsForWildcards(includes, absolutePath, "files"), function (pattern) { return "^" + pattern + "$"; }),
@@ -14565,8 +14597,8 @@ var ts;
     ts.getRegexFromPattern = getRegexFromPattern;
     /** @param path directory of the tsconfig.json */
     function matchFiles(path, extensions, excludes, includes, useCaseSensitiveFileNames, currentDirectory, depth, getFileSystemEntries) {
-        path = normalizePath(path);
-        currentDirectory = normalizePath(currentDirectory);
+        path = ts.normalizePath(path);
+        currentDirectory = ts.normalizePath(currentDirectory);
         var patterns = getFileMatcherPatterns(path, excludes, includes, useCaseSensitiveFileNames, currentDirectory);
         var includeFileRegexes = patterns.includeFilePatterns && patterns.includeFilePatterns.map(function (pattern) { return getRegexFromPattern(pattern, useCaseSensitiveFileNames); });
         var includeDirectoryRegex = patterns.includeDirectoryPattern && getRegexFromPattern(patterns.includeDirectoryPattern, useCaseSensitiveFileNames);
@@ -14633,7 +14665,7 @@ var ts;
                 var include = includes_1[_i];
                 // We also need to check the relative paths by converting them to absolute and normalizing
                 // in case they escape the base path (e.g "..\somedirectory")
-                var absolute = isRootedDiskPath(include) ? include : normalizePath(combinePaths(path, include));
+                var absolute = ts.isRootedDiskPath(include) ? include : ts.normalizePath(combinePaths(path, include));
                 // Append the literal and canonical candidate base paths.
                 includeBasePaths.push(getIncludeBasePath(absolute));
             }
@@ -14659,7 +14691,7 @@ var ts;
             // No "*" or "?" in the path
             return !hasExtension(absolute)
                 ? absolute
-                : removeTrailingDirectorySeparator(getDirectoryPath(absolute));
+                : removeTrailingDirectorySeparator(ts.getDirectoryPath(absolute));
         }
         return absolute.substring(0, absolute.lastIndexOf(ts.directorySeparator, wildcardOffset));
     }
@@ -14836,7 +14868,7 @@ var ts;
     })(Debug = ts.Debug || (ts.Debug = {}));
     function tryParsePattern(pattern) {
         // This should be verified outside of here and a proper error thrown.
-        Debug.assert(hasZeroOrOneAsteriskCharacter(pattern));
+        Debug.assert(ts.hasZeroOrOneAsteriskCharacter(pattern));
         var indexOfStar = pattern.indexOf("*");
         return indexOfStar === -1 ? undefined : {
             prefix: pattern.substr(0, indexOfStar),
@@ -14879,8 +14911,8 @@ var ts;
     function getAnyExtensionFromPathWorker(path, extensions, stringEqualityComparer) {
         if (typeof extensions === "string")
             extensions = [extensions];
-        for (var _i = 0, extensions_1 = extensions; _i < extensions_1.length; _i++) {
-            var extension = extensions_1[_i];
+        for (var _i = 0, extensions_2 = extensions; _i < extensions_2.length; _i++) {
+            var extension = extensions_2[_i];
             if (!ts.startsWith(extension, "."))
                 extension = "." + extension;
             if (path.length >= extension.length && path.charAt(path.length - extension.length) === ".") {
@@ -21353,8 +21385,8 @@ var ts;
                 array._children = undefined;
                 array.pos += delta;
                 array.end += delta;
-                for (var _i = 0, array_1 = array; _i < array_1.length; _i++) {
-                    var node = array_1[_i];
+                for (var _i = 0, array_8 = array; _i < array_8.length; _i++) {
+                    var node = array_8[_i];
                     visitNode(node);
                 }
             }
@@ -21504,8 +21536,8 @@ var ts;
                     array._children = undefined;
                     // Adjust the pos or end (or both) of the intersecting array accordingly.
                     adjustIntersectingElement(array, changeStart, changeRangeOldEnd, changeRangeNewEnd, delta);
-                    for (var _i = 0, array_2 = array; _i < array_2.length; _i++) {
-                        var node = array_2[_i];
+                    for (var _i = 0, array_9 = array; _i < array_9.length; _i++) {
+                        var node = array_9[_i];
                         visitNode(node);
                     }
                     return;
@@ -25341,8 +25373,60901 @@ var ts;
         return value !== undefined ? { value: value } : undefined;
     }
 })(ts || (ts = {}));
-//# sourceMappingURL=parser.js.map
+/* @internal */
+var ts;
+(function (ts) {
+    var ModuleInstanceState;
+    (function (ModuleInstanceState) {
+        ModuleInstanceState[ModuleInstanceState["NonInstantiated"] = 0] = "NonInstantiated";
+        ModuleInstanceState[ModuleInstanceState["Instantiated"] = 1] = "Instantiated";
+        ModuleInstanceState[ModuleInstanceState["ConstEnumOnly"] = 2] = "ConstEnumOnly";
+    })(ModuleInstanceState = ts.ModuleInstanceState || (ts.ModuleInstanceState = {}));
+    function getModuleInstanceState(node) {
+        return node.body ? getModuleInstanceStateWorker(node.body) : 1 /* Instantiated */;
+    }
+    ts.getModuleInstanceState = getModuleInstanceState;
+    function getModuleInstanceStateWorker(node) {
+        // A module is uninstantiated if it contains only
+        switch (node.kind) {
+            // 1. interface declarations, type alias declarations
+            case 236 /* InterfaceDeclaration */:
+            case 237 /* TypeAliasDeclaration */:
+                return 0 /* NonInstantiated */;
+            // 2. const enum declarations
+            case 238 /* EnumDeclaration */:
+                if (ts.isConst(node)) {
+                    return 2 /* ConstEnumOnly */;
+                }
+                break;
+            // 3. non-exported import declarations
+            case 244 /* ImportDeclaration */:
+            case 243 /* ImportEqualsDeclaration */:
+                if (!(ts.hasModifier(node, 1 /* Export */))) {
+                    return 0 /* NonInstantiated */;
+                }
+                break;
+            // 4. other uninstantiated module declarations.
+            case 240 /* ModuleBlock */: {
+                var state_1 = 0 /* NonInstantiated */;
+                ts.forEachChild(node, function (n) {
+                    var childState = getModuleInstanceStateWorker(n);
+                    switch (childState) {
+                        case 0 /* NonInstantiated */:
+                            // child is non-instantiated - continue searching
+                            return;
+                        case 2 /* ConstEnumOnly */:
+                            // child is const enum only - record state and continue searching
+                            state_1 = 2 /* ConstEnumOnly */;
+                            return;
+                        case 1 /* Instantiated */:
+                            // child is instantiated - record state and stop
+                            state_1 = 1 /* Instantiated */;
+                            return true;
+                        default:
+                            ts.Debug.assertNever(childState);
+                    }
+                });
+                return state_1;
+            }
+            case 239 /* ModuleDeclaration */:
+                return getModuleInstanceState(node);
+            case 71 /* Identifier */:
+                // Only jsdoc typedef definition can exist in jsdoc namespace, and it should
+                // be considered the same as type alias
+                if (node.isInJSDocNamespace) {
+                    return 0 /* NonInstantiated */;
+                }
+        }
+        return 1 /* Instantiated */;
+    }
+    var ContainerFlags;
+    (function (ContainerFlags) {
+        // The current node is not a container, and no container manipulation should happen before
+        // recursing into it.
+        ContainerFlags[ContainerFlags["None"] = 0] = "None";
+        // The current node is a container.  It should be set as the current container (and block-
+        // container) before recursing into it.  The current node does not have locals.  Examples:
+        //
+        //      Classes, ObjectLiterals, TypeLiterals, Interfaces...
+        ContainerFlags[ContainerFlags["IsContainer"] = 1] = "IsContainer";
+        // The current node is a block-scoped-container.  It should be set as the current block-
+        // container before recursing into it.  Examples:
+        //
+        //      Blocks (when not parented by functions), Catch clauses, For/For-in/For-of statements...
+        ContainerFlags[ContainerFlags["IsBlockScopedContainer"] = 2] = "IsBlockScopedContainer";
+        // The current node is the container of a control flow path. The current control flow should
+        // be saved and restored, and a new control flow initialized within the container.
+        ContainerFlags[ContainerFlags["IsControlFlowContainer"] = 4] = "IsControlFlowContainer";
+        ContainerFlags[ContainerFlags["IsFunctionLike"] = 8] = "IsFunctionLike";
+        ContainerFlags[ContainerFlags["IsFunctionExpression"] = 16] = "IsFunctionExpression";
+        ContainerFlags[ContainerFlags["HasLocals"] = 32] = "HasLocals";
+        ContainerFlags[ContainerFlags["IsInterface"] = 64] = "IsInterface";
+        ContainerFlags[ContainerFlags["IsObjectLiteralOrClassExpressionMethod"] = 128] = "IsObjectLiteralOrClassExpressionMethod";
+    })(ContainerFlags || (ContainerFlags = {}));
+    var binder = createBinder();
+    function bindSourceFile(file, options) {
+        ts.performance.mark("beforeBind");
+        binder(file, options);
+        ts.performance.mark("afterBind");
+        ts.performance.measure("Bind", "beforeBind", "afterBind");
+    }
+    ts.bindSourceFile = bindSourceFile;
+    function createBinder() {
+        var file;
+        var options;
+        var languageVersion;
+        var parent;
+        var container;
+        var thisParentContainer; // Container one level up
+        var blockScopeContainer;
+        var lastContainer;
+        var delayedTypeAliases;
+        var seenThisKeyword;
+        // state used by control flow analysis
+        var currentFlow;
+        var currentBreakTarget;
+        var currentContinueTarget;
+        var currentReturnTarget;
+        var currentTrueTarget;
+        var currentFalseTarget;
+        var preSwitchCaseFlow;
+        var activeLabels;
+        var hasExplicitReturn;
+        // state used for emit helpers
+        var emitFlags;
+        // If this file is an external module, then it is automatically in strict-mode according to
+        // ES6.  If it is not an external module, then we'll determine if it is in strict mode or
+        // not depending on if we see "use strict" in certain places or if we hit a class/namespace
+        // or if compiler options contain alwaysStrict.
+        var inStrictMode;
+        var symbolCount = 0;
+        var Symbol; // tslint:disable-line variable-name
+        var classifiableNames;
+        var unreachableFlow = { flags: 1 /* Unreachable */ };
+        var reportedUnreachableFlow = { flags: 1 /* Unreachable */ };
+        // state used to aggregate transform flags during bind.
+        var subtreeTransformFlags = 0 /* None */;
+        var skipTransformFlagAggregation;
+        /**
+         * Inside the binder, we may create a diagnostic for an as-yet unbound node (with potentially no parent pointers, implying no accessible source file)
+         * If so, the node _must_ be in the current file (as that's the only way anything could have traversed to it to yield it as the error node)
+         * This version of `createDiagnosticForNode` uses the binder's context to account for this, and always yields correct diagnostics even in these situations.
+         */
+        function createDiagnosticForNode(node, message, arg0, arg1, arg2) {
+            return ts.createDiagnosticForNodeInSourceFile(ts.getSourceFileOfNode(node) || file, node, message, arg0, arg1, arg2);
+        }
+        function bindSourceFile(f, opts) {
+            file = f;
+            options = opts;
+            languageVersion = ts.getEmitScriptTarget(options);
+            inStrictMode = bindInStrictMode(file, opts);
+            classifiableNames = ts.createUnderscoreEscapedMap();
+            symbolCount = 0;
+            skipTransformFlagAggregation = file.isDeclarationFile;
+            Symbol = ts.objectAllocator.getSymbolConstructor();
+            if (!file.locals) {
+                bind(file);
+                file.symbolCount = symbolCount;
+                file.classifiableNames = classifiableNames;
+                delayedBindJSDocTypedefTag();
+            }
+            file = undefined;
+            options = undefined;
+            languageVersion = undefined;
+            parent = undefined;
+            container = undefined;
+            thisParentContainer = undefined;
+            blockScopeContainer = undefined;
+            lastContainer = undefined;
+            delayedTypeAliases = undefined;
+            seenThisKeyword = false;
+            currentFlow = undefined;
+            currentBreakTarget = undefined;
+            currentContinueTarget = undefined;
+            currentReturnTarget = undefined;
+            currentTrueTarget = undefined;
+            currentFalseTarget = undefined;
+            activeLabels = undefined;
+            hasExplicitReturn = false;
+            emitFlags = 0 /* None */;
+            subtreeTransformFlags = 0 /* None */;
+        }
+        return bindSourceFile;
+        function bindInStrictMode(file, opts) {
+            if (ts.getStrictOptionValue(opts, "alwaysStrict") && !file.isDeclarationFile) {
+                // bind in strict mode source files with alwaysStrict option
+                return true;
+            }
+            else {
+                return !!file.externalModuleIndicator;
+            }
+        }
+        function createSymbol(flags, name) {
+            symbolCount++;
+            return new Symbol(flags, name);
+        }
+        function addDeclarationToSymbol(symbol, node, symbolFlags) {
+            symbol.flags |= symbolFlags;
+            node.symbol = symbol;
+            symbol.declarations = ts.append(symbol.declarations, node);
+            if (symbolFlags & 1955 /* HasExports */ && !symbol.exports) {
+                symbol.exports = ts.createSymbolTable();
+            }
+            if (symbolFlags & 6240 /* HasMembers */ && !symbol.members) {
+                symbol.members = ts.createSymbolTable();
+            }
+            if (symbolFlags & 67216319 /* Value */) {
+                var valueDeclaration = symbol.valueDeclaration;
+                if (!valueDeclaration ||
+                    (valueDeclaration.kind !== node.kind && ts.isEffectiveModuleDeclaration(valueDeclaration))) {
+                    // other kinds of value declarations take precedence over modules
+                    symbol.valueDeclaration = node;
+                }
+            }
+        }
+        // Should not be called on a declaration with a computed property name,
+        // unless it is a well known Symbol.
+        function getDeclarationName(node) {
+            if (node.kind === 249 /* ExportAssignment */) {
+                return node.isExportEquals ? "export=" /* ExportEquals */ : "default" /* Default */;
+            }
+            var name = ts.getNameOfDeclaration(node);
+            if (name) {
+                if (ts.isAmbientModule(node)) {
+                    var moduleName = ts.getTextOfIdentifierOrLiteral(name);
+                    return (ts.isGlobalScopeAugmentation(node) ? "__global" : "\"" + moduleName + "\"");
+                }
+                if (name.kind === 147 /* ComputedPropertyName */) {
+                    var nameExpression = name.expression;
+                    // treat computed property names where expression is string/numeric literal as just string/numeric literal
+                    if (ts.isStringOrNumericLiteral(nameExpression)) {
+                        return ts.escapeLeadingUnderscores(nameExpression.text);
+                    }
+                    ts.Debug.assert(ts.isWellKnownSymbolSyntactically(nameExpression));
+                    return ts.getPropertyNameForKnownSymbolName(ts.idText(nameExpression.name));
+                }
+                return ts.isPropertyNameLiteral(name) ? ts.getEscapedTextOfIdentifierOrLiteral(name) : undefined;
+            }
+            switch (node.kind) {
+                case 155 /* Constructor */:
+                    return "__constructor" /* Constructor */;
+                case 163 /* FunctionType */:
+                case 158 /* CallSignature */:
+                case 288 /* JSDocSignature */:
+                    return "__call" /* Call */;
+                case 164 /* ConstructorType */:
+                case 159 /* ConstructSignature */:
+                    return "__new" /* New */;
+                case 160 /* IndexSignature */:
+                    return "__index" /* Index */;
+                case 250 /* ExportDeclaration */:
+                    return "__export" /* ExportStar */;
+                case 274 /* SourceFile */:
+                    // json file should behave as
+                    // module.exports = ...
+                    return "export=" /* ExportEquals */;
+                case 200 /* BinaryExpression */:
+                    if (ts.getSpecialPropertyAssignmentKind(node) === 2 /* ModuleExports */) {
+                        // module.exports = ...
+                        return "export=" /* ExportEquals */;
+                    }
+                    ts.Debug.fail("Unknown binary declaration kind");
+                    break;
+                case 284 /* JSDocFunctionType */:
+                    return (ts.isJSDocConstructSignature(node) ? "__new" /* New */ : "__call" /* Call */);
+                case 149 /* Parameter */:
+                    // Parameters with names are handled at the top of this function.  Parameters
+                    // without names can only come from JSDocFunctionTypes.
+                    ts.Debug.assert(node.parent.kind === 284 /* JSDocFunctionType */, "Impossible parameter parent kind", function () { return "parent is: " + (ts.SyntaxKind ? ts.SyntaxKind[node.parent.kind] : node.parent.kind) + ", expected JSDocFunctionType"; });
+                    var functionType = node.parent;
+                    var index = functionType.parameters.indexOf(node);
+                    return "arg" + index;
+            }
+        }
+        function getDisplayName(node) {
+            return ts.isNamedDeclaration(node) ? ts.declarationNameToString(node.name) : ts.unescapeLeadingUnderscores(getDeclarationName(node)); // TODO: GH#18217
+        }
+        /**
+         * Declares a Symbol for the node and adds it to symbols. Reports errors for conflicting identifier names.
+         * @param symbolTable - The symbol table which node will be added to.
+         * @param parent - node's parent declaration.
+         * @param node - The declaration to be added to the symbol table
+         * @param includes - The SymbolFlags that node has in addition to its declaration type (eg: export, ambient, etc.)
+         * @param excludes - The flags which node cannot be declared alongside in a symbol table. Used to report forbidden declarations.
+         */
+        function declareSymbol(symbolTable, parent, node, includes, excludes, isReplaceableByMethod) {
+            ts.Debug.assert(!ts.hasDynamicName(node));
+            var isDefaultExport = ts.hasModifier(node, 512 /* Default */);
+            // The exported symbol for an export default function/class node is always named "default"
+            var name = isDefaultExport && parent ? "default" /* Default */ : getDeclarationName(node);
+            var symbol;
+            if (name === undefined) {
+                symbol = createSymbol(0 /* None */, "__missing" /* Missing */);
+            }
+            else {
+                // Check and see if the symbol table already has a symbol with this name.  If not,
+                // create a new symbol with this name and add it to the table.  Note that we don't
+                // give the new symbol any flags *yet*.  This ensures that it will not conflict
+                // with the 'excludes' flags we pass in.
+                //
+                // If we do get an existing symbol, see if it conflicts with the new symbol we're
+                // creating.  For example, a 'var' symbol and a 'class' symbol will conflict within
+                // the same symbol table.  If we have a conflict, report the issue on each
+                // declaration we have for this symbol, and then create a new symbol for this
+                // declaration.
+                //
+                // Note that when properties declared in Javascript constructors
+                // (marked by isReplaceableByMethod) conflict with another symbol, the property loses.
+                // Always. This allows the common Javascript pattern of overwriting a prototype method
+                // with an bound instance method of the same type: `this.method = this.method.bind(this)`
+                //
+                // If we created a new symbol, either because we didn't have a symbol with this name
+                // in the symbol table, or we conflicted with an existing symbol, then just add this
+                // node as the sole declaration of the new symbol.
+                //
+                // Otherwise, we'll be merging into a compatible existing symbol (for example when
+                // you have multiple 'vars' with the same name in the same container).  In this case
+                // just add this node into the declarations list of the symbol.
+                symbol = symbolTable.get(name);
+                if (includes & 2885600 /* Classifiable */) {
+                    classifiableNames.set(name, true);
+                }
+                if (!symbol) {
+                    symbolTable.set(name, symbol = createSymbol(0 /* None */, name));
+                    if (isReplaceableByMethod)
+                        symbol.isReplaceableByMethod = true;
+                }
+                else if (isReplaceableByMethod && !symbol.isReplaceableByMethod) {
+                    // A symbol already exists, so don't add this as a declaration.
+                    return symbol;
+                }
+                else if (symbol.flags & excludes) {
+                    if (symbol.isReplaceableByMethod) {
+                        // Javascript constructor-declared symbols can be discarded in favor of
+                        // prototype symbols like methods.
+                        symbolTable.set(name, symbol = createSymbol(0 /* None */, name));
+                    }
+                    else {
+                        if (ts.isNamedDeclaration(node)) {
+                            node.name.parent = node;
+                        }
+                        // Report errors every position with duplicate declaration
+                        // Report errors on previous encountered declarations
+                        var message_1 = symbol.flags & 2 /* BlockScopedVariable */
+                            ? ts.Diagnostics.Cannot_redeclare_block_scoped_variable_0
+                            : ts.Diagnostics.Duplicate_identifier_0;
+                        if (symbol.flags & 384 /* Enum */ || includes & 384 /* Enum */) {
+                            message_1 = ts.Diagnostics.Enum_declarations_can_only_merge_with_namespace_or_other_enum_declarations;
+                        }
+                        if (symbol.declarations && symbol.declarations.length) {
+                            // If the current node is a default export of some sort, then check if
+                            // there are any other default exports that we need to error on.
+                            // We'll know whether we have other default exports depending on if `symbol` already has a declaration list set.
+                            if (isDefaultExport) {
+                                message_1 = ts.Diagnostics.A_module_cannot_have_multiple_default_exports;
+                            }
+                            else {
+                                // This is to properly report an error in the case "export default { }" is after export default of class declaration or function declaration.
+                                // Error on multiple export default in the following case:
+                                // 1. multiple export default of class declaration or function declaration by checking NodeFlags.Default
+                                // 2. multiple export default of export assignment. This one doesn't have NodeFlags.Default on (as export default doesn't considered as modifiers)
+                                if (symbol.declarations && symbol.declarations.length &&
+                                    (node.kind === 249 /* ExportAssignment */ && !node.isExportEquals)) {
+                                    message_1 = ts.Diagnostics.A_module_cannot_have_multiple_default_exports;
+                                }
+                            }
+                        }
+                        ts.forEach(symbol.declarations, function (declaration) {
+                            file.bindDiagnostics.push(createDiagnosticForNode(ts.getNameOfDeclaration(declaration) || declaration, message_1, getDisplayName(declaration)));
+                        });
+                        file.bindDiagnostics.push(createDiagnosticForNode(ts.getNameOfDeclaration(node) || node, message_1, getDisplayName(node)));
+                        symbol = createSymbol(0 /* None */, name);
+                    }
+                }
+            }
+            addDeclarationToSymbol(symbol, node, includes);
+            if (symbol.parent) {
+                ts.Debug.assert(symbol.parent === parent, "Existing symbol parent should match new one");
+            }
+            else {
+                symbol.parent = parent;
+            }
+            return symbol;
+        }
+        function declareModuleMember(node, symbolFlags, symbolExcludes) {
+            var hasExportModifier = ts.getCombinedModifierFlags(node) & 1 /* Export */;
+            if (symbolFlags & 2097152 /* Alias */) {
+                if (node.kind === 252 /* ExportSpecifier */ || (node.kind === 243 /* ImportEqualsDeclaration */ && hasExportModifier)) {
+                    return declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes);
+                }
+                else {
+                    return declareSymbol(container.locals, /*parent*/ undefined, node, symbolFlags, symbolExcludes);
+                }
+            }
+            else {
+                // Exported module members are given 2 symbols: A local symbol that is classified with an ExportValue flag,
+                // and an associated export symbol with all the correct flags set on it. There are 2 main reasons:
+                //
+                //   1. We treat locals and exports of the same name as mutually exclusive within a container.
+                //      That means the binder will issue a Duplicate Identifier error if you mix locals and exports
+                //      with the same name in the same container.
+                //      TODO: Make this a more specific error and decouple it from the exclusion logic.
+                //   2. When we checkIdentifier in the checker, we set its resolved symbol to the local symbol,
+                //      but return the export symbol (by calling getExportSymbolOfValueSymbolIfExported). That way
+                //      when the emitter comes back to it, it knows not to qualify the name if it was found in a containing scope.
+                // NOTE: Nested ambient modules always should go to to 'locals' table to prevent their automatic merge
+                //       during global merging in the checker. Why? The only case when ambient module is permitted inside another module is module augmentation
+                //       and this case is specially handled. Module augmentations should only be merged with original module definition
+                //       and should never be merged directly with other augmentation, and the latter case would be possible if automatic merge is allowed.
+                if (ts.isJSDocTypeAlias(node))
+                    ts.Debug.assert(ts.isInJavaScriptFile(node)); // We shouldn't add symbols for JSDoc nodes if not in a JS file.
+                if ((!ts.isAmbientModule(node) && (hasExportModifier || container.flags & 32 /* ExportContext */)) || ts.isJSDocTypeAlias(node)) {
+                    if (ts.hasModifier(node, 512 /* Default */) && !getDeclarationName(node)) {
+                        return declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes); // No local symbol for an unnamed default!
+                    }
+                    var exportKind = symbolFlags & 67216319 /* Value */ ? 1048576 /* ExportValue */ : 0;
+                    var local = declareSymbol(container.locals, /*parent*/ undefined, node, exportKind, symbolExcludes);
+                    local.exportSymbol = declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes);
+                    node.localSymbol = local;
+                    return local;
+                }
+                else {
+                    return declareSymbol(container.locals, /*parent*/ undefined, node, symbolFlags, symbolExcludes);
+                }
+            }
+        }
+        // All container nodes are kept on a linked list in declaration order. This list is used by
+        // the getLocalNameOfContainer function in the type checker to validate that the local name
+        // used for a container is unique.
+        function bindContainer(node, containerFlags) {
+            // Before we recurse into a node's children, we first save the existing parent, container
+            // and block-container.  Then after we pop out of processing the children, we restore
+            // these saved values.
+            var saveContainer = container;
+            var saveThisParentContainer = thisParentContainer;
+            var savedBlockScopeContainer = blockScopeContainer;
+            // Depending on what kind of node this is, we may have to adjust the current container
+            // and block-container.   If the current node is a container, then it is automatically
+            // considered the current block-container as well.  Also, for containers that we know
+            // may contain locals, we eagerly initialize the .locals field. We do this because
+            // it's highly likely that the .locals will be needed to place some child in (for example,
+            // a parameter, or variable declaration).
+            //
+            // However, we do not proactively create the .locals for block-containers because it's
+            // totally normal and common for block-containers to never actually have a block-scoped
+            // variable in them.  We don't want to end up allocating an object for every 'block' we
+            // run into when most of them won't be necessary.
+            //
+            // Finally, if this is a block-container, then we clear out any existing .locals object
+            // it may contain within it.  This happens in incremental scenarios.  Because we can be
+            // reusing a node from a previous compilation, that node may have had 'locals' created
+            // for it.  We must clear this so we don't accidentally move any stale data forward from
+            // a previous compilation.
+            if (containerFlags & 1 /* IsContainer */) {
+                if (node.kind !== 193 /* ArrowFunction */) {
+                    thisParentContainer = container;
+                }
+                container = blockScopeContainer = node;
+                if (containerFlags & 32 /* HasLocals */) {
+                    container.locals = ts.createSymbolTable();
+                }
+                addToContainerChain(container);
+            }
+            else if (containerFlags & 2 /* IsBlockScopedContainer */) {
+                blockScopeContainer = node;
+                blockScopeContainer.locals = undefined;
+            }
+            if (containerFlags & 4 /* IsControlFlowContainer */) {
+                var saveCurrentFlow = currentFlow;
+                var saveBreakTarget = currentBreakTarget;
+                var saveContinueTarget = currentContinueTarget;
+                var saveReturnTarget = currentReturnTarget;
+                var saveActiveLabels = activeLabels;
+                var saveHasExplicitReturn = hasExplicitReturn;
+                var isIIFE = containerFlags & 16 /* IsFunctionExpression */ && !ts.hasModifier(node, 256 /* Async */) &&
+                    !node.asteriskToken && !!ts.getImmediatelyInvokedFunctionExpression(node);
+                // A non-async, non-generator IIFE is considered part of the containing control flow. Return statements behave
+                // similarly to break statements that exit to a label just past the statement body.
+                if (!isIIFE) {
+                    currentFlow = { flags: 2 /* Start */ };
+                    if (containerFlags & (16 /* IsFunctionExpression */ | 128 /* IsObjectLiteralOrClassExpressionMethod */)) {
+                        currentFlow.container = node;
+                    }
+                }
+                // We create a return control flow graph for IIFEs and constructors. For constructors
+                // we use the return control flow graph in strict property intialization checks.
+                currentReturnTarget = isIIFE || node.kind === 155 /* Constructor */ ? createBranchLabel() : undefined;
+                currentBreakTarget = undefined;
+                currentContinueTarget = undefined;
+                activeLabels = undefined;
+                hasExplicitReturn = false;
+                bindChildren(node);
+                // Reset all reachability check related flags on node (for incremental scenarios)
+                node.flags &= ~1408 /* ReachabilityAndEmitFlags */;
+                if (!(currentFlow.flags & 1 /* Unreachable */) && containerFlags & 8 /* IsFunctionLike */ && ts.nodeIsPresent(node.body)) {
+                    node.flags |= 128 /* HasImplicitReturn */;
+                    if (hasExplicitReturn)
+                        node.flags |= 256 /* HasExplicitReturn */;
+                }
+                if (node.kind === 274 /* SourceFile */) {
+                    node.flags |= emitFlags;
+                }
+                if (currentReturnTarget) {
+                    addAntecedent(currentReturnTarget, currentFlow);
+                    currentFlow = finishFlowLabel(currentReturnTarget);
+                    if (node.kind === 155 /* Constructor */) {
+                        node.returnFlowNode = currentFlow;
+                    }
+                }
+                if (!isIIFE) {
+                    currentFlow = saveCurrentFlow;
+                }
+                currentBreakTarget = saveBreakTarget;
+                currentContinueTarget = saveContinueTarget;
+                currentReturnTarget = saveReturnTarget;
+                activeLabels = saveActiveLabels;
+                hasExplicitReturn = saveHasExplicitReturn;
+            }
+            else if (containerFlags & 64 /* IsInterface */) {
+                seenThisKeyword = false;
+                bindChildren(node);
+                node.flags = seenThisKeyword ? node.flags | 64 /* ContainsThis */ : node.flags & ~64 /* ContainsThis */;
+            }
+            else {
+                bindChildren(node);
+            }
+            container = saveContainer;
+            thisParentContainer = saveThisParentContainer;
+            blockScopeContainer = savedBlockScopeContainer;
+        }
+        function bindChildren(node) {
+            if (skipTransformFlagAggregation) {
+                bindChildrenWorker(node);
+            }
+            else if (node.transformFlags & 536870912 /* HasComputedFlags */) {
+                skipTransformFlagAggregation = true;
+                bindChildrenWorker(node);
+                skipTransformFlagAggregation = false;
+                subtreeTransformFlags |= node.transformFlags & ~getTransformFlagsSubtreeExclusions(node.kind);
+            }
+            else {
+                var savedSubtreeTransformFlags = subtreeTransformFlags;
+                subtreeTransformFlags = 0;
+                bindChildrenWorker(node);
+                subtreeTransformFlags = savedSubtreeTransformFlags | computeTransformFlagsForNode(node, subtreeTransformFlags);
+            }
+        }
+        function bindEachFunctionsFirst(nodes) {
+            bindEach(nodes, function (n) { return n.kind === 234 /* FunctionDeclaration */ ? bind(n) : undefined; });
+            bindEach(nodes, function (n) { return n.kind !== 234 /* FunctionDeclaration */ ? bind(n) : undefined; });
+        }
+        function bindEach(nodes, bindFunction) {
+            if (bindFunction === void 0) { bindFunction = bind; }
+            if (nodes === undefined) {
+                return;
+            }
+            if (skipTransformFlagAggregation) {
+                ts.forEach(nodes, bindFunction);
+            }
+            else {
+                var savedSubtreeTransformFlags = subtreeTransformFlags;
+                subtreeTransformFlags = 0 /* None */;
+                var nodeArrayFlags = 0 /* None */;
+                for (var _i = 0, nodes_2 = nodes; _i < nodes_2.length; _i++) {
+                    var node = nodes_2[_i];
+                    bindFunction(node);
+                    nodeArrayFlags |= node.transformFlags & ~536870912 /* HasComputedFlags */;
+                }
+                nodes.transformFlags = nodeArrayFlags | 536870912 /* HasComputedFlags */;
+                subtreeTransformFlags |= savedSubtreeTransformFlags;
+            }
+        }
+        function bindEachChild(node) {
+            ts.forEachChild(node, bind, bindEach);
+        }
+        function bindChildrenWorker(node) {
+            if (checkUnreachable(node)) {
+                bindEachChild(node);
+                return;
+            }
+            switch (node.kind) {
+                case 219 /* WhileStatement */:
+                    bindWhileStatement(node);
+                    break;
+                case 218 /* DoStatement */:
+                    bindDoStatement(node);
+                    break;
+                case 220 /* ForStatement */:
+                    bindForStatement(node);
+                    break;
+                case 221 /* ForInStatement */:
+                case 222 /* ForOfStatement */:
+                    bindForInOrForOfStatement(node);
+                    break;
+                case 217 /* IfStatement */:
+                    bindIfStatement(node);
+                    break;
+                case 225 /* ReturnStatement */:
+                case 229 /* ThrowStatement */:
+                    bindReturnOrThrow(node);
+                    break;
+                case 224 /* BreakStatement */:
+                case 223 /* ContinueStatement */:
+                    bindBreakOrContinueStatement(node);
+                    break;
+                case 230 /* TryStatement */:
+                    bindTryStatement(node);
+                    break;
+                case 227 /* SwitchStatement */:
+                    bindSwitchStatement(node);
+                    break;
+                case 241 /* CaseBlock */:
+                    bindCaseBlock(node);
+                    break;
+                case 266 /* CaseClause */:
+                    bindCaseClause(node);
+                    break;
+                case 228 /* LabeledStatement */:
+                    bindLabeledStatement(node);
+                    break;
+                case 198 /* PrefixUnaryExpression */:
+                    bindPrefixUnaryExpressionFlow(node);
+                    break;
+                case 199 /* PostfixUnaryExpression */:
+                    bindPostfixUnaryExpressionFlow(node);
+                    break;
+                case 200 /* BinaryExpression */:
+                    bindBinaryExpressionFlow(node);
+                    break;
+                case 194 /* DeleteExpression */:
+                    bindDeleteExpressionFlow(node);
+                    break;
+                case 201 /* ConditionalExpression */:
+                    bindConditionalExpressionFlow(node);
+                    break;
+                case 232 /* VariableDeclaration */:
+                    bindVariableDeclarationFlow(node);
+                    break;
+                case 187 /* CallExpression */:
+                    bindCallExpressionFlow(node);
+                    break;
+                case 297 /* JSDocTypedefTag */:
+                case 292 /* JSDocCallbackTag */:
+                    bindJSDocTypeAlias(node);
+                    break;
+                // In source files and blocks, bind functions first to match hoisting that occurs at runtime
+                case 274 /* SourceFile */:
+                    bindEachFunctionsFirst(node.statements);
+                    bind(node.endOfFileToken);
+                    break;
+                case 213 /* Block */:
+                case 240 /* ModuleBlock */:
+                    bindEachFunctionsFirst(node.statements);
+                    break;
+                default:
+                    bindEachChild(node);
+                    break;
+            }
+            bindJSDoc(node);
+        }
+        function isNarrowingExpression(expr) {
+            switch (expr.kind) {
+                case 71 /* Identifier */:
+                case 99 /* ThisKeyword */:
+                case 185 /* PropertyAccessExpression */:
+                    return isNarrowableReference(expr);
+                case 187 /* CallExpression */:
+                    return hasNarrowableArgument(expr);
+                case 191 /* ParenthesizedExpression */:
+                    return isNarrowingExpression(expr.expression);
+                case 200 /* BinaryExpression */:
+                    return isNarrowingBinaryExpression(expr);
+                case 198 /* PrefixUnaryExpression */:
+                    return expr.operator === 51 /* ExclamationToken */ && isNarrowingExpression(expr.operand);
+            }
+            return false;
+        }
+        function isNarrowableReference(expr) {
+            return expr.kind === 71 /* Identifier */ ||
+                expr.kind === 99 /* ThisKeyword */ ||
+                expr.kind === 97 /* SuperKeyword */ ||
+                expr.kind === 185 /* PropertyAccessExpression */ && isNarrowableReference(expr.expression);
+        }
+        function hasNarrowableArgument(expr) {
+            if (expr.arguments) {
+                for (var _i = 0, _a = expr.arguments; _i < _a.length; _i++) {
+                    var argument = _a[_i];
+                    if (isNarrowableReference(argument)) {
+                        return true;
+                    }
+                }
+            }
+            if (expr.expression.kind === 185 /* PropertyAccessExpression */ &&
+                isNarrowableReference(expr.expression.expression)) {
+                return true;
+            }
+            return false;
+        }
+        function isNarrowingTypeofOperands(expr1, expr2) {
+            return ts.isTypeOfExpression(expr1) && isNarrowableOperand(expr1.expression) && ts.isStringLiteralLike(expr2);
+        }
+        function isNarrowableInOperands(left, right) {
+            return ts.isStringLiteralLike(left) && isNarrowingExpression(right);
+        }
+        function isNarrowingBinaryExpression(expr) {
+            switch (expr.operatorToken.kind) {
+                case 58 /* EqualsToken */:
+                    return isNarrowableReference(expr.left);
+                case 32 /* EqualsEqualsToken */:
+                case 33 /* ExclamationEqualsToken */:
+                case 34 /* EqualsEqualsEqualsToken */:
+                case 35 /* ExclamationEqualsEqualsToken */:
+                    return isNarrowableOperand(expr.left) || isNarrowableOperand(expr.right) ||
+                        isNarrowingTypeofOperands(expr.right, expr.left) || isNarrowingTypeofOperands(expr.left, expr.right);
+                case 93 /* InstanceOfKeyword */:
+                    return isNarrowableOperand(expr.left);
+                case 92 /* InKeyword */:
+                    return isNarrowableInOperands(expr.left, expr.right);
+                case 26 /* CommaToken */:
+                    return isNarrowingExpression(expr.right);
+            }
+            return false;
+        }
+        function isNarrowableOperand(expr) {
+            switch (expr.kind) {
+                case 191 /* ParenthesizedExpression */:
+                    return isNarrowableOperand(expr.expression);
+                case 200 /* BinaryExpression */:
+                    switch (expr.operatorToken.kind) {
+                        case 58 /* EqualsToken */:
+                            return isNarrowableOperand(expr.left);
+                        case 26 /* CommaToken */:
+                            return isNarrowableOperand(expr.right);
+                    }
+            }
+            return isNarrowableReference(expr);
+        }
+        function createBranchLabel() {
+            return {
+                flags: 4 /* BranchLabel */,
+                antecedents: undefined
+            };
+        }
+        function createLoopLabel() {
+            return {
+                flags: 8 /* LoopLabel */,
+                antecedents: undefined
+            };
+        }
+        function setFlowNodeReferenced(flow) {
+            // On first reference we set the Referenced flag, thereafter we set the Shared flag
+            flow.flags |= flow.flags & 512 /* Referenced */ ? 1024 /* Shared */ : 512 /* Referenced */;
+        }
+        function addAntecedent(label, antecedent) {
+            if (!(antecedent.flags & 1 /* Unreachable */) && !ts.contains(label.antecedents, antecedent)) {
+                (label.antecedents || (label.antecedents = [])).push(antecedent);
+                setFlowNodeReferenced(antecedent);
+            }
+        }
+        function createFlowCondition(flags, antecedent, expression) {
+            if (antecedent.flags & 1 /* Unreachable */) {
+                return antecedent;
+            }
+            if (!expression) {
+                return flags & 32 /* TrueCondition */ ? antecedent : unreachableFlow;
+            }
+            if (expression.kind === 101 /* TrueKeyword */ && flags & 64 /* FalseCondition */ ||
+                expression.kind === 86 /* FalseKeyword */ && flags & 32 /* TrueCondition */) {
+                return unreachableFlow;
+            }
+            if (!isNarrowingExpression(expression)) {
+                return antecedent;
+            }
+            setFlowNodeReferenced(antecedent);
+            return { flags: flags, expression: expression, antecedent: antecedent };
+        }
+        function createFlowSwitchClause(antecedent, switchStatement, clauseStart, clauseEnd) {
+            if (!isNarrowingExpression(switchStatement.expression)) {
+                return antecedent;
+            }
+            setFlowNodeReferenced(antecedent);
+            return { flags: 128 /* SwitchClause */, switchStatement: switchStatement, clauseStart: clauseStart, clauseEnd: clauseEnd, antecedent: antecedent };
+        }
+        function createFlowAssignment(antecedent, node) {
+            setFlowNodeReferenced(antecedent);
+            return { flags: 16 /* Assignment */, antecedent: antecedent, node: node };
+        }
+        function createFlowArrayMutation(antecedent, node) {
+            setFlowNodeReferenced(antecedent);
+            var res = { flags: 256 /* ArrayMutation */, antecedent: antecedent, node: node };
+            return res;
+        }
+        function finishFlowLabel(flow) {
+            var antecedents = flow.antecedents;
+            if (!antecedents) {
+                return unreachableFlow;
+            }
+            if (antecedents.length === 1) {
+                return antecedents[0];
+            }
+            return flow;
+        }
+        function isStatementCondition(node) {
+            var parent = node.parent;
+            switch (parent.kind) {
+                case 217 /* IfStatement */:
+                case 219 /* WhileStatement */:
+                case 218 /* DoStatement */:
+                    return parent.expression === node;
+                case 220 /* ForStatement */:
+                case 201 /* ConditionalExpression */:
+                    return parent.condition === node;
+            }
+            return false;
+        }
+        function isLogicalExpression(node) {
+            while (true) {
+                if (node.kind === 191 /* ParenthesizedExpression */) {
+                    node = node.expression;
+                }
+                else if (node.kind === 198 /* PrefixUnaryExpression */ && node.operator === 51 /* ExclamationToken */) {
+                    node = node.operand;
+                }
+                else {
+                    return node.kind === 200 /* BinaryExpression */ && (node.operatorToken.kind === 53 /* AmpersandAmpersandToken */ ||
+                        node.operatorToken.kind === 54 /* BarBarToken */);
+                }
+            }
+        }
+        function isTopLevelLogicalExpression(node) {
+            while (node.parent.kind === 191 /* ParenthesizedExpression */ ||
+                node.parent.kind === 198 /* PrefixUnaryExpression */ &&
+                    node.parent.operator === 51 /* ExclamationToken */) {
+                node = node.parent;
+            }
+            return !isStatementCondition(node) && !isLogicalExpression(node.parent);
+        }
+        function bindCondition(node, trueTarget, falseTarget) {
+            var saveTrueTarget = currentTrueTarget;
+            var saveFalseTarget = currentFalseTarget;
+            currentTrueTarget = trueTarget;
+            currentFalseTarget = falseTarget;
+            bind(node);
+            currentTrueTarget = saveTrueTarget;
+            currentFalseTarget = saveFalseTarget;
+            if (!node || !isLogicalExpression(node)) {
+                addAntecedent(trueTarget, createFlowCondition(32 /* TrueCondition */, currentFlow, node));
+                addAntecedent(falseTarget, createFlowCondition(64 /* FalseCondition */, currentFlow, node));
+            }
+        }
+        function bindIterativeStatement(node, breakTarget, continueTarget) {
+            var saveBreakTarget = currentBreakTarget;
+            var saveContinueTarget = currentContinueTarget;
+            currentBreakTarget = breakTarget;
+            currentContinueTarget = continueTarget;
+            bind(node);
+            currentBreakTarget = saveBreakTarget;
+            currentContinueTarget = saveContinueTarget;
+        }
+        function bindWhileStatement(node) {
+            var preWhileLabel = createLoopLabel();
+            var preBodyLabel = createBranchLabel();
+            var postWhileLabel = createBranchLabel();
+            addAntecedent(preWhileLabel, currentFlow);
+            currentFlow = preWhileLabel;
+            bindCondition(node.expression, preBodyLabel, postWhileLabel);
+            currentFlow = finishFlowLabel(preBodyLabel);
+            bindIterativeStatement(node.statement, postWhileLabel, preWhileLabel);
+            addAntecedent(preWhileLabel, currentFlow);
+            currentFlow = finishFlowLabel(postWhileLabel);
+        }
+        function bindDoStatement(node) {
+            var preDoLabel = createLoopLabel();
+            var enclosingLabeledStatement = node.parent.kind === 228 /* LabeledStatement */
+                ? ts.lastOrUndefined(activeLabels)
+                : undefined;
+            // if do statement is wrapped in labeled statement then target labels for break/continue with or without
+            // label should be the same
+            var preConditionLabel = enclosingLabeledStatement ? enclosingLabeledStatement.continueTarget : createBranchLabel();
+            var postDoLabel = enclosingLabeledStatement ? enclosingLabeledStatement.breakTarget : createBranchLabel();
+            addAntecedent(preDoLabel, currentFlow);
+            currentFlow = preDoLabel;
+            bindIterativeStatement(node.statement, postDoLabel, preConditionLabel);
+            addAntecedent(preConditionLabel, currentFlow);
+            currentFlow = finishFlowLabel(preConditionLabel);
+            bindCondition(node.expression, preDoLabel, postDoLabel);
+            currentFlow = finishFlowLabel(postDoLabel);
+        }
+        function bindForStatement(node) {
+            var preLoopLabel = createLoopLabel();
+            var preBodyLabel = createBranchLabel();
+            var postLoopLabel = createBranchLabel();
+            bind(node.initializer);
+            addAntecedent(preLoopLabel, currentFlow);
+            currentFlow = preLoopLabel;
+            bindCondition(node.condition, preBodyLabel, postLoopLabel);
+            currentFlow = finishFlowLabel(preBodyLabel);
+            bindIterativeStatement(node.statement, postLoopLabel, preLoopLabel);
+            bind(node.incrementor);
+            addAntecedent(preLoopLabel, currentFlow);
+            currentFlow = finishFlowLabel(postLoopLabel);
+        }
+        function bindForInOrForOfStatement(node) {
+            var preLoopLabel = createLoopLabel();
+            var postLoopLabel = createBranchLabel();
+            addAntecedent(preLoopLabel, currentFlow);
+            currentFlow = preLoopLabel;
+            if (node.kind === 222 /* ForOfStatement */) {
+                bind(node.awaitModifier);
+            }
+            bind(node.expression);
+            addAntecedent(postLoopLabel, currentFlow);
+            bind(node.initializer);
+            if (node.initializer.kind !== 233 /* VariableDeclarationList */) {
+                bindAssignmentTargetFlow(node.initializer);
+            }
+            bindIterativeStatement(node.statement, postLoopLabel, preLoopLabel);
+            addAntecedent(preLoopLabel, currentFlow);
+            currentFlow = finishFlowLabel(postLoopLabel);
+        }
+        function bindIfStatement(node) {
+            var thenLabel = createBranchLabel();
+            var elseLabel = createBranchLabel();
+            var postIfLabel = createBranchLabel();
+            bindCondition(node.expression, thenLabel, elseLabel);
+            currentFlow = finishFlowLabel(thenLabel);
+            bind(node.thenStatement);
+            addAntecedent(postIfLabel, currentFlow);
+            currentFlow = finishFlowLabel(elseLabel);
+            bind(node.elseStatement);
+            addAntecedent(postIfLabel, currentFlow);
+            currentFlow = finishFlowLabel(postIfLabel);
+        }
+        function bindReturnOrThrow(node) {
+            bind(node.expression);
+            if (node.kind === 225 /* ReturnStatement */) {
+                hasExplicitReturn = true;
+                if (currentReturnTarget) {
+                    addAntecedent(currentReturnTarget, currentFlow);
+                }
+            }
+            currentFlow = unreachableFlow;
+        }
+        function findActiveLabel(name) {
+            if (activeLabels) {
+                for (var _i = 0, activeLabels_1 = activeLabels; _i < activeLabels_1.length; _i++) {
+                    var label = activeLabels_1[_i];
+                    if (label.name === name) {
+                        return label;
+                    }
+                }
+            }
+            return undefined;
+        }
+        function bindBreakOrContinueFlow(node, breakTarget, continueTarget) {
+            var flowLabel = node.kind === 224 /* BreakStatement */ ? breakTarget : continueTarget;
+            if (flowLabel) {
+                addAntecedent(flowLabel, currentFlow);
+                currentFlow = unreachableFlow;
+            }
+        }
+        function bindBreakOrContinueStatement(node) {
+            bind(node.label);
+            if (node.label) {
+                var activeLabel = findActiveLabel(node.label.escapedText);
+                if (activeLabel) {
+                    activeLabel.referenced = true;
+                    bindBreakOrContinueFlow(node, activeLabel.breakTarget, activeLabel.continueTarget);
+                }
+            }
+            else {
+                bindBreakOrContinueFlow(node, currentBreakTarget, currentContinueTarget);
+            }
+        }
+        function bindTryStatement(node) {
+            var preFinallyLabel = createBranchLabel();
+            var preTryFlow = currentFlow;
+            // TODO: Every statement in try block is potentially an exit point!
+            bind(node.tryBlock);
+            addAntecedent(preFinallyLabel, currentFlow);
+            var flowAfterTry = currentFlow;
+            var flowAfterCatch = unreachableFlow;
+            if (node.catchClause) {
+                currentFlow = preTryFlow;
+                bind(node.catchClause);
+                addAntecedent(preFinallyLabel, currentFlow);
+                flowAfterCatch = currentFlow;
+            }
+            if (node.finallyBlock) {
+                // in finally flow is combined from pre-try/flow from try/flow from catch
+                // pre-flow is necessary to make sure that finally is reachable even if finally flows in both try and finally blocks are unreachable
+                // also for finally blocks we inject two extra edges into the flow graph.
+                // first -> edge that connects pre-try flow with the label at the beginning of the finally block, it has lock associated with it
+                // second -> edge that represents post-finally flow.
+                // these edges are used in following scenario:
+                // let a; (1)
+                // try { a = someOperation(); (2)}
+                // finally { (3) console.log(a) } (4)
+                // (5) a
+                // flow graph for this case looks roughly like this (arrows show ):
+                // (1-pre-try-flow) <--.. <-- (2-post-try-flow)
+                //  ^                                ^
+                //  |*****(3-pre-finally-label) -----|
+                //                ^
+                //                |-- ... <-- (4-post-finally-label) <--- (5)
+                // In case when we walk the flow starting from inside the finally block we want to take edge '*****' into account
+                // since it ensures that finally is always reachable. However when we start outside the finally block and go through label (5)
+                // then edge '*****' should be discarded because label 4 is only reachable if post-finally label-4 is reachable
+                // Simply speaking code inside finally block is treated as reachable as pre-try-flow
+                // since we conservatively assume that any line in try block can throw or return in which case we'll enter finally.
+                // However code after finally is reachable only if control flow was not abrupted in try/catch or finally blocks - it should be composed from
+                // final flows of these blocks without taking pre-try flow into account.
+                //
+                // extra edges that we inject allows to control this behavior
+                // if when walking the flow we step on post-finally edge - we can mark matching pre-finally edge as locked so it will be skipped.
+                var preFinallyFlow = { flags: 2048 /* PreFinally */, antecedent: preTryFlow, lock: {} };
+                addAntecedent(preFinallyLabel, preFinallyFlow);
+                currentFlow = finishFlowLabel(preFinallyLabel);
+                bind(node.finallyBlock);
+                // if flow after finally is unreachable - keep it
+                // otherwise check if flows after try and after catch are unreachable
+                // if yes - convert current flow to unreachable
+                // i.e.
+                // try { return "1" } finally { console.log(1); }
+                // console.log(2); // this line should be unreachable even if flow falls out of finally block
+                if (!(currentFlow.flags & 1 /* Unreachable */)) {
+                    if ((flowAfterTry.flags & 1 /* Unreachable */) && (flowAfterCatch.flags & 1 /* Unreachable */)) {
+                        currentFlow = flowAfterTry === reportedUnreachableFlow || flowAfterCatch === reportedUnreachableFlow
+                            ? reportedUnreachableFlow
+                            : unreachableFlow;
+                    }
+                }
+                if (!(currentFlow.flags & 1 /* Unreachable */)) {
+                    var afterFinallyFlow = { flags: 4096 /* AfterFinally */, antecedent: currentFlow };
+                    preFinallyFlow.lock = afterFinallyFlow;
+                    currentFlow = afterFinallyFlow;
+                }
+            }
+            else {
+                currentFlow = finishFlowLabel(preFinallyLabel);
+            }
+        }
+        function bindSwitchStatement(node) {
+            var postSwitchLabel = createBranchLabel();
+            bind(node.expression);
+            var saveBreakTarget = currentBreakTarget;
+            var savePreSwitchCaseFlow = preSwitchCaseFlow;
+            currentBreakTarget = postSwitchLabel;
+            preSwitchCaseFlow = currentFlow;
+            bind(node.caseBlock);
+            addAntecedent(postSwitchLabel, currentFlow);
+            var hasDefault = ts.forEach(node.caseBlock.clauses, function (c) { return c.kind === 267 /* DefaultClause */; });
+            // We mark a switch statement as possibly exhaustive if it has no default clause and if all
+            // case clauses have unreachable end points (e.g. they all return).
+            node.possiblyExhaustive = !hasDefault && !postSwitchLabel.antecedents;
+            if (!hasDefault) {
+                addAntecedent(postSwitchLabel, createFlowSwitchClause(preSwitchCaseFlow, node, 0, 0));
+            }
+            currentBreakTarget = saveBreakTarget;
+            preSwitchCaseFlow = savePreSwitchCaseFlow;
+            currentFlow = finishFlowLabel(postSwitchLabel);
+        }
+        function bindCaseBlock(node) {
+            var savedSubtreeTransformFlags = subtreeTransformFlags;
+            subtreeTransformFlags = 0;
+            var clauses = node.clauses;
+            var fallthroughFlow = unreachableFlow;
+            for (var i = 0; i < clauses.length; i++) {
+                var clauseStart = i;
+                while (!clauses[i].statements.length && i + 1 < clauses.length) {
+                    bind(clauses[i]);
+                    i++;
+                }
+                var preCaseLabel = createBranchLabel();
+                addAntecedent(preCaseLabel, createFlowSwitchClause(preSwitchCaseFlow, node.parent, clauseStart, i + 1));
+                addAntecedent(preCaseLabel, createFlowSwitchClause(preSwitchCaseFlow, node.parent, clauseStart, i + 1));
+                addAntecedent(preCaseLabel, fallthroughFlow);
+                currentFlow = finishFlowLabel(preCaseLabel);
+                var clause = clauses[i];
+                bind(clause);
+                fallthroughFlow = currentFlow;
+                if (!(currentFlow.flags & 1 /* Unreachable */) && i !== clauses.length - 1 && options.noFallthroughCasesInSwitch) {
+                    errorOnFirstToken(clause, ts.Diagnostics.Fallthrough_case_in_switch);
+                }
+            }
+            clauses.transformFlags = subtreeTransformFlags | 536870912 /* HasComputedFlags */;
+            subtreeTransformFlags |= savedSubtreeTransformFlags;
+        }
+        function bindCaseClause(node) {
+            var saveCurrentFlow = currentFlow;
+            currentFlow = preSwitchCaseFlow;
+            bind(node.expression);
+            currentFlow = saveCurrentFlow;
+            bindEach(node.statements);
+        }
+        function pushActiveLabel(name, breakTarget, continueTarget) {
+            var activeLabel = {
+                name: name,
+                breakTarget: breakTarget,
+                continueTarget: continueTarget,
+                referenced: false
+            };
+            (activeLabels || (activeLabels = [])).push(activeLabel);
+            return activeLabel;
+        }
+        function popActiveLabel() {
+            activeLabels.pop();
+        }
+        function bindLabeledStatement(node) {
+            var preStatementLabel = createLoopLabel();
+            var postStatementLabel = createBranchLabel();
+            bind(node.label);
+            addAntecedent(preStatementLabel, currentFlow);
+            var activeLabel = pushActiveLabel(node.label.escapedText, postStatementLabel, preStatementLabel);
+            bind(node.statement);
+            popActiveLabel();
+            if (!activeLabel.referenced && !options.allowUnusedLabels) {
+                errorOrSuggestionOnFirstToken(ts.unusedLabelIsError(options), node, ts.Diagnostics.Unused_label);
+            }
+            if (!node.statement || node.statement.kind !== 218 /* DoStatement */) {
+                // do statement sets current flow inside bindDoStatement
+                addAntecedent(postStatementLabel, currentFlow);
+                currentFlow = finishFlowLabel(postStatementLabel);
+            }
+        }
+        function bindDestructuringTargetFlow(node) {
+            if (node.kind === 200 /* BinaryExpression */ && node.operatorToken.kind === 58 /* EqualsToken */) {
+                bindAssignmentTargetFlow(node.left);
+            }
+            else {
+                bindAssignmentTargetFlow(node);
+            }
+        }
+        function bindAssignmentTargetFlow(node) {
+            if (isNarrowableReference(node)) {
+                currentFlow = createFlowAssignment(currentFlow, node);
+            }
+            else if (node.kind === 183 /* ArrayLiteralExpression */) {
+                for (var _i = 0, _a = node.elements; _i < _a.length; _i++) {
+                    var e = _a[_i];
+                    if (e.kind === 204 /* SpreadElement */) {
+                        bindAssignmentTargetFlow(e.expression);
+                    }
+                    else {
+                        bindDestructuringTargetFlow(e);
+                    }
+                }
+            }
+            else if (node.kind === 184 /* ObjectLiteralExpression */) {
+                for (var _b = 0, _c = node.properties; _b < _c.length; _b++) {
+                    var p = _c[_b];
+                    if (p.kind === 270 /* PropertyAssignment */) {
+                        bindDestructuringTargetFlow(p.initializer);
+                    }
+                    else if (p.kind === 271 /* ShorthandPropertyAssignment */) {
+                        bindAssignmentTargetFlow(p.name);
+                    }
+                    else if (p.kind === 272 /* SpreadAssignment */) {
+                        bindAssignmentTargetFlow(p.expression);
+                    }
+                }
+            }
+        }
+        function bindLogicalExpression(node, trueTarget, falseTarget) {
+            var preRightLabel = createBranchLabel();
+            if (node.operatorToken.kind === 53 /* AmpersandAmpersandToken */) {
+                bindCondition(node.left, preRightLabel, falseTarget);
+            }
+            else {
+                bindCondition(node.left, trueTarget, preRightLabel);
+            }
+            currentFlow = finishFlowLabel(preRightLabel);
+            bind(node.operatorToken);
+            bindCondition(node.right, trueTarget, falseTarget);
+        }
+        function bindPrefixUnaryExpressionFlow(node) {
+            if (node.operator === 51 /* ExclamationToken */) {
+                var saveTrueTarget = currentTrueTarget;
+                currentTrueTarget = currentFalseTarget;
+                currentFalseTarget = saveTrueTarget;
+                bindEachChild(node);
+                currentFalseTarget = currentTrueTarget;
+                currentTrueTarget = saveTrueTarget;
+            }
+            else {
+                bindEachChild(node);
+                if (node.operator === 43 /* PlusPlusToken */ || node.operator === 44 /* MinusMinusToken */) {
+                    bindAssignmentTargetFlow(node.operand);
+                }
+            }
+        }
+        function bindPostfixUnaryExpressionFlow(node) {
+            bindEachChild(node);
+            if (node.operator === 43 /* PlusPlusToken */ || node.operator === 44 /* MinusMinusToken */) {
+                bindAssignmentTargetFlow(node.operand);
+            }
+        }
+        function bindBinaryExpressionFlow(node) {
+            var operator = node.operatorToken.kind;
+            if (operator === 53 /* AmpersandAmpersandToken */ || operator === 54 /* BarBarToken */) {
+                if (isTopLevelLogicalExpression(node)) {
+                    var postExpressionLabel = createBranchLabel();
+                    bindLogicalExpression(node, postExpressionLabel, postExpressionLabel);
+                    currentFlow = finishFlowLabel(postExpressionLabel);
+                }
+                else {
+                    bindLogicalExpression(node, currentTrueTarget, currentFalseTarget);
+                }
+            }
+            else {
+                bindEachChild(node);
+                if (ts.isAssignmentOperator(operator) && !ts.isAssignmentTarget(node)) {
+                    bindAssignmentTargetFlow(node.left);
+                    if (operator === 58 /* EqualsToken */ && node.left.kind === 186 /* ElementAccessExpression */) {
+                        var elementAccess = node.left;
+                        if (isNarrowableOperand(elementAccess.expression)) {
+                            currentFlow = createFlowArrayMutation(currentFlow, node);
+                        }
+                    }
+                }
+            }
+        }
+        function bindDeleteExpressionFlow(node) {
+            bindEachChild(node);
+            if (node.expression.kind === 185 /* PropertyAccessExpression */) {
+                bindAssignmentTargetFlow(node.expression);
+            }
+        }
+        function bindConditionalExpressionFlow(node) {
+            var trueLabel = createBranchLabel();
+            var falseLabel = createBranchLabel();
+            var postExpressionLabel = createBranchLabel();
+            bindCondition(node.condition, trueLabel, falseLabel);
+            currentFlow = finishFlowLabel(trueLabel);
+            bind(node.questionToken);
+            bind(node.whenTrue);
+            addAntecedent(postExpressionLabel, currentFlow);
+            currentFlow = finishFlowLabel(falseLabel);
+            bind(node.colonToken);
+            bind(node.whenFalse);
+            addAntecedent(postExpressionLabel, currentFlow);
+            currentFlow = finishFlowLabel(postExpressionLabel);
+        }
+        function bindInitializedVariableFlow(node) {
+            var name = !ts.isOmittedExpression(node) ? node.name : undefined;
+            if (ts.isBindingPattern(name)) {
+                for (var _i = 0, _a = name.elements; _i < _a.length; _i++) {
+                    var child = _a[_i];
+                    bindInitializedVariableFlow(child);
+                }
+            }
+            else {
+                currentFlow = createFlowAssignment(currentFlow, node);
+            }
+        }
+        function bindVariableDeclarationFlow(node) {
+            bindEachChild(node);
+            if (node.initializer || ts.isForInOrOfStatement(node.parent.parent)) {
+                bindInitializedVariableFlow(node);
+            }
+        }
+        function bindJSDocTypeAlias(node) {
+            if (node.fullName) {
+                setParentPointers(node, node.fullName);
+            }
+        }
+        function bindCallExpressionFlow(node) {
+            // If the target of the call expression is a function expression or arrow function we have
+            // an immediately invoked function expression (IIFE). Initialize the flowNode property to
+            // the current control flow (which includes evaluation of the IIFE arguments).
+            var expr = node.expression;
+            while (expr.kind === 191 /* ParenthesizedExpression */) {
+                expr = expr.expression;
+            }
+            if (expr.kind === 192 /* FunctionExpression */ || expr.kind === 193 /* ArrowFunction */) {
+                bindEach(node.typeArguments);
+                bindEach(node.arguments);
+                bind(node.expression);
+            }
+            else {
+                bindEachChild(node);
+            }
+            if (node.expression.kind === 185 /* PropertyAccessExpression */) {
+                var propertyAccess = node.expression;
+                if (isNarrowableOperand(propertyAccess.expression) && ts.isPushOrUnshiftIdentifier(propertyAccess.name)) {
+                    currentFlow = createFlowArrayMutation(currentFlow, node);
+                }
+            }
+        }
+        function getContainerFlags(node) {
+            switch (node.kind) {
+                case 205 /* ClassExpression */:
+                case 235 /* ClassDeclaration */:
+                case 238 /* EnumDeclaration */:
+                case 184 /* ObjectLiteralExpression */:
+                case 166 /* TypeLiteral */:
+                case 287 /* JSDocTypeLiteral */:
+                case 263 /* JsxAttributes */:
+                    return 1 /* IsContainer */;
+                case 236 /* InterfaceDeclaration */:
+                    return 1 /* IsContainer */ | 64 /* IsInterface */;
+                case 239 /* ModuleDeclaration */:
+                case 237 /* TypeAliasDeclaration */:
+                case 177 /* MappedType */:
+                    return 1 /* IsContainer */ | 32 /* HasLocals */;
+                case 274 /* SourceFile */:
+                    return 1 /* IsContainer */ | 4 /* IsControlFlowContainer */ | 32 /* HasLocals */;
+                case 154 /* MethodDeclaration */:
+                    if (ts.isObjectLiteralOrClassExpressionMethod(node)) {
+                        return 1 /* IsContainer */ | 4 /* IsControlFlowContainer */ | 32 /* HasLocals */ | 8 /* IsFunctionLike */ | 128 /* IsObjectLiteralOrClassExpressionMethod */;
+                    }
+                // falls through
+                case 155 /* Constructor */:
+                case 234 /* FunctionDeclaration */:
+                case 153 /* MethodSignature */:
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                case 158 /* CallSignature */:
+                case 288 /* JSDocSignature */:
+                case 284 /* JSDocFunctionType */:
+                case 163 /* FunctionType */:
+                case 159 /* ConstructSignature */:
+                case 160 /* IndexSignature */:
+                case 164 /* ConstructorType */:
+                    return 1 /* IsContainer */ | 4 /* IsControlFlowContainer */ | 32 /* HasLocals */ | 8 /* IsFunctionLike */;
+                case 192 /* FunctionExpression */:
+                case 193 /* ArrowFunction */:
+                    return 1 /* IsContainer */ | 4 /* IsControlFlowContainer */ | 32 /* HasLocals */ | 8 /* IsFunctionLike */ | 16 /* IsFunctionExpression */;
+                case 240 /* ModuleBlock */:
+                    return 4 /* IsControlFlowContainer */;
+                case 152 /* PropertyDeclaration */:
+                    return node.initializer ? 4 /* IsControlFlowContainer */ : 0;
+                case 269 /* CatchClause */:
+                case 220 /* ForStatement */:
+                case 221 /* ForInStatement */:
+                case 222 /* ForOfStatement */:
+                case 241 /* CaseBlock */:
+                    return 2 /* IsBlockScopedContainer */;
+                case 213 /* Block */:
+                    // do not treat blocks directly inside a function as a block-scoped-container.
+                    // Locals that reside in this block should go to the function locals. Otherwise 'x'
+                    // would not appear to be a redeclaration of a block scoped local in the following
+                    // example:
+                    //
+                    //      function foo() {
+                    //          var x;
+                    //          let x;
+                    //      }
+                    //
+                    // If we placed 'var x' into the function locals and 'let x' into the locals of
+                    // the block, then there would be no collision.
+                    //
+                    // By not creating a new block-scoped-container here, we ensure that both 'var x'
+                    // and 'let x' go into the Function-container's locals, and we do get a collision
+                    // conflict.
+                    return ts.isFunctionLike(node.parent) ? 0 /* None */ : 2 /* IsBlockScopedContainer */;
+            }
+            return 0 /* None */;
+        }
+        function addToContainerChain(next) {
+            if (lastContainer) {
+                lastContainer.nextContainer = next;
+            }
+            lastContainer = next;
+        }
+        function declareSymbolAndAddToSymbolTable(node, symbolFlags, symbolExcludes) {
+            switch (container.kind) {
+                // Modules, source files, and classes need specialized handling for how their
+                // members are declared (for example, a member of a class will go into a specific
+                // symbol table depending on if it is static or not). We defer to specialized
+                // handlers to take care of declaring these child members.
+                case 239 /* ModuleDeclaration */:
+                    return declareModuleMember(node, symbolFlags, symbolExcludes);
+                case 274 /* SourceFile */:
+                    return declareSourceFileMember(node, symbolFlags, symbolExcludes);
+                case 205 /* ClassExpression */:
+                case 235 /* ClassDeclaration */:
+                    return declareClassMember(node, symbolFlags, symbolExcludes);
+                case 238 /* EnumDeclaration */:
+                    return declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes);
+                case 166 /* TypeLiteral */:
+                case 287 /* JSDocTypeLiteral */:
+                case 184 /* ObjectLiteralExpression */:
+                case 236 /* InterfaceDeclaration */:
+                case 263 /* JsxAttributes */:
+                    // Interface/Object-types always have their children added to the 'members' of
+                    // their container. They are only accessible through an instance of their
+                    // container, and are never in scope otherwise (even inside the body of the
+                    // object / type / interface declaring them). An exception is type parameters,
+                    // which are in scope without qualification (similar to 'locals').
+                    return declareSymbol(container.symbol.members, container.symbol, node, symbolFlags, symbolExcludes);
+                case 163 /* FunctionType */:
+                case 164 /* ConstructorType */:
+                case 158 /* CallSignature */:
+                case 159 /* ConstructSignature */:
+                case 288 /* JSDocSignature */:
+                case 160 /* IndexSignature */:
+                case 154 /* MethodDeclaration */:
+                case 153 /* MethodSignature */:
+                case 155 /* Constructor */:
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                case 234 /* FunctionDeclaration */:
+                case 192 /* FunctionExpression */:
+                case 193 /* ArrowFunction */:
+                case 284 /* JSDocFunctionType */:
+                case 297 /* JSDocTypedefTag */:
+                case 292 /* JSDocCallbackTag */:
+                case 237 /* TypeAliasDeclaration */:
+                case 177 /* MappedType */:
+                    // All the children of these container types are never visible through another
+                    // symbol (i.e. through another symbol's 'exports' or 'members').  Instead,
+                    // they're only accessed 'lexically' (i.e. from code that exists underneath
+                    // their container in the tree). To accomplish this, we simply add their declared
+                    // symbol to the 'locals' of the container.  These symbols can then be found as
+                    // the type checker walks up the containers, checking them for matching names.
+                    return declareSymbol(container.locals, /*parent*/ undefined, node, symbolFlags, symbolExcludes);
+            }
+        }
+        function declareClassMember(node, symbolFlags, symbolExcludes) {
+            return ts.hasModifier(node, 32 /* Static */)
+                ? declareSymbol(container.symbol.exports, container.symbol, node, symbolFlags, symbolExcludes)
+                : declareSymbol(container.symbol.members, container.symbol, node, symbolFlags, symbolExcludes);
+        }
+        function declareSourceFileMember(node, symbolFlags, symbolExcludes) {
+            return ts.isExternalModule(file)
+                ? declareModuleMember(node, symbolFlags, symbolExcludes)
+                : declareSymbol(file.locals, /*parent*/ undefined, node, symbolFlags, symbolExcludes);
+        }
+        function hasExportDeclarations(node) {
+            var body = node.kind === 274 /* SourceFile */ ? node : node.body;
+            if (body && (body.kind === 274 /* SourceFile */ || body.kind === 240 /* ModuleBlock */)) {
+                for (var _i = 0, _a = body.statements; _i < _a.length; _i++) {
+                    var stat = _a[_i];
+                    if (stat.kind === 250 /* ExportDeclaration */ || stat.kind === 249 /* ExportAssignment */) {
+                        return true;
+                    }
+                }
+            }
+            return false;
+        }
+        function setExportContextFlag(node) {
+            // A declaration source file or ambient module declaration that contains no export declarations (but possibly regular
+            // declarations with export modifiers) is an export context in which declarations are implicitly exported.
+            if (node.flags & 4194304 /* Ambient */ && !hasExportDeclarations(node)) {
+                node.flags |= 32 /* ExportContext */;
+            }
+            else {
+                node.flags &= ~32 /* ExportContext */;
+            }
+        }
+        function bindModuleDeclaration(node) {
+            setExportContextFlag(node);
+            if (ts.isAmbientModule(node)) {
+                if (ts.hasModifier(node, 1 /* Export */)) {
+                    errorOnFirstToken(node, ts.Diagnostics.export_modifier_cannot_be_applied_to_ambient_modules_and_module_augmentations_since_they_are_always_visible);
+                }
+                if (ts.isModuleAugmentationExternal(node)) {
+                    declareModuleSymbol(node);
+                }
+                else {
+                    var pattern = void 0;
+                    if (node.name.kind === 9 /* StringLiteral */) {
+                        var text = node.name.text;
+                        if (ts.hasZeroOrOneAsteriskCharacter(text)) {
+                            pattern = ts.tryParsePattern(text);
+                        }
+                        else {
+                            errorOnFirstToken(node.name, ts.Diagnostics.Pattern_0_can_have_at_most_one_Asterisk_character, text);
+                        }
+                    }
+                    var symbol = declareSymbolAndAddToSymbolTable(node, 512 /* ValueModule */, 67215503 /* ValueModuleExcludes */);
+                    file.patternAmbientModules = ts.append(file.patternAmbientModules, pattern && { pattern: pattern, symbol: symbol });
+                }
+            }
+            else {
+                var state = declareModuleSymbol(node);
+                if (state !== 0 /* NonInstantiated */) {
+                    var symbol = node.symbol;
+                    // if module was already merged with some function, class or non-const enum, treat it as non-const-enum-only
+                    symbol.constEnumOnlyModule = (!(symbol.flags & (16 /* Function */ | 32 /* Class */ | 256 /* RegularEnum */)))
+                        // Current must be `const enum` only
+                        && state === 2 /* ConstEnumOnly */
+                        // Can't have been set to 'false' in a previous merged symbol. ('undefined' OK)
+                        && symbol.constEnumOnlyModule !== false;
+                }
+            }
+        }
+        function declareModuleSymbol(node) {
+            var state = getModuleInstanceState(node);
+            var instantiated = state !== 0 /* NonInstantiated */;
+            declareSymbolAndAddToSymbolTable(node, instantiated ? 512 /* ValueModule */ : 1024 /* NamespaceModule */, instantiated ? 67215503 /* ValueModuleExcludes */ : 0 /* NamespaceModuleExcludes */);
+            return state;
+        }
+        function bindFunctionOrConstructorType(node) {
+            // For a given function symbol "<...>(...) => T" we want to generate a symbol identical
+            // to the one we would get for: { <...>(...): T }
+            //
+            // We do that by making an anonymous type literal symbol, and then setting the function
+            // symbol as its sole member. To the rest of the system, this symbol will be indistinguishable
+            // from an actual type literal symbol you would have gotten had you used the long form.
+            var symbol = createSymbol(131072 /* Signature */, getDeclarationName(node)); // TODO: GH#18217
+            addDeclarationToSymbol(symbol, node, 131072 /* Signature */);
+            var typeLiteralSymbol = createSymbol(2048 /* TypeLiteral */, "__type" /* Type */);
+            addDeclarationToSymbol(typeLiteralSymbol, node, 2048 /* TypeLiteral */);
+            typeLiteralSymbol.members = ts.createSymbolTable();
+            typeLiteralSymbol.members.set(symbol.escapedName, symbol);
+        }
+        function bindObjectLiteralExpression(node) {
+            var ElementKind;
+            (function (ElementKind) {
+                ElementKind[ElementKind["Property"] = 1] = "Property";
+                ElementKind[ElementKind["Accessor"] = 2] = "Accessor";
+            })(ElementKind || (ElementKind = {}));
+            if (inStrictMode) {
+                var seen = ts.createUnderscoreEscapedMap();
+                for (var _i = 0, _a = node.properties; _i < _a.length; _i++) {
+                    var prop = _a[_i];
+                    if (prop.kind === 272 /* SpreadAssignment */ || prop.name.kind !== 71 /* Identifier */) {
+                        continue;
+                    }
+                    var identifier = prop.name;
+                    // ECMA-262 11.1.5 Object Initializer
+                    // If previous is not undefined then throw a SyntaxError exception if any of the following conditions are true
+                    // a.This production is contained in strict code and IsDataDescriptor(previous) is true and
+                    // IsDataDescriptor(propId.descriptor) is true.
+                    //    b.IsDataDescriptor(previous) is true and IsAccessorDescriptor(propId.descriptor) is true.
+                    //    c.IsAccessorDescriptor(previous) is true and IsDataDescriptor(propId.descriptor) is true.
+                    //    d.IsAccessorDescriptor(previous) is true and IsAccessorDescriptor(propId.descriptor) is true
+                    // and either both previous and propId.descriptor have[[Get]] fields or both previous and propId.descriptor have[[Set]] fields
+                    var currentKind = prop.kind === 270 /* PropertyAssignment */ || prop.kind === 271 /* ShorthandPropertyAssignment */ || prop.kind === 154 /* MethodDeclaration */
+                        ? 1 /* Property */
+                        : 2 /* Accessor */;
+                    var existingKind = seen.get(identifier.escapedText);
+                    if (!existingKind) {
+                        seen.set(identifier.escapedText, currentKind);
+                        continue;
+                    }
+                    if (currentKind === 1 /* Property */ && existingKind === 1 /* Property */) {
+                        var span = ts.getErrorSpanForNode(file, identifier);
+                        file.bindDiagnostics.push(ts.createFileDiagnostic(file, span.start, span.length, ts.Diagnostics.An_object_literal_cannot_have_multiple_properties_with_the_same_name_in_strict_mode));
+                    }
+                }
+            }
+            return bindAnonymousDeclaration(node, 4096 /* ObjectLiteral */, "__object" /* Object */);
+        }
+        function bindJsxAttributes(node) {
+            return bindAnonymousDeclaration(node, 4096 /* ObjectLiteral */, "__jsxAttributes" /* JSXAttributes */);
+        }
+        function bindJsxAttribute(node, symbolFlags, symbolExcludes) {
+            return declareSymbolAndAddToSymbolTable(node, symbolFlags, symbolExcludes);
+        }
+        function bindAnonymousDeclaration(node, symbolFlags, name) {
+            var symbol = createSymbol(symbolFlags, name);
+            if (symbolFlags & (8 /* EnumMember */ | 106500 /* ClassMember */)) {
+                symbol.parent = container.symbol;
+            }
+            addDeclarationToSymbol(symbol, node, symbolFlags);
+            return symbol;
+        }
+        function bindBlockScopedDeclaration(node, symbolFlags, symbolExcludes) {
+            switch (blockScopeContainer.kind) {
+                case 239 /* ModuleDeclaration */:
+                    declareModuleMember(node, symbolFlags, symbolExcludes);
+                    break;
+                case 274 /* SourceFile */:
+                    if (ts.isExternalOrCommonJsModule(container)) {
+                        declareModuleMember(node, symbolFlags, symbolExcludes);
+                        break;
+                    }
+                // falls through
+                default:
+                    if (!blockScopeContainer.locals) {
+                        blockScopeContainer.locals = ts.createSymbolTable();
+                        addToContainerChain(blockScopeContainer);
+                    }
+                    declareSymbol(blockScopeContainer.locals, /*parent*/ undefined, node, symbolFlags, symbolExcludes);
+            }
+        }
+        function bindBlockScopedVariableDeclaration(node) {
+            bindBlockScopedDeclaration(node, 2 /* BlockScopedVariable */, 67216319 /* BlockScopedVariableExcludes */);
+        }
+        function delayedBindJSDocTypedefTag() {
+            if (!delayedTypeAliases) {
+                return;
+            }
+            var saveContainer = container;
+            var saveLastContainer = lastContainer;
+            var saveBlockScopeContainer = blockScopeContainer;
+            var saveParent = parent;
+            var saveCurrentFlow = currentFlow;
+            for (var _i = 0, delayedTypeAliases_1 = delayedTypeAliases; _i < delayedTypeAliases_1.length; _i++) {
+                var typeAlias = delayedTypeAliases_1[_i];
+                var host = ts.getJSDocHost(typeAlias);
+                container = ts.findAncestor(host.parent, function (n) { return !!(getContainerFlags(n) & 1 /* IsContainer */); }) || file;
+                blockScopeContainer = ts.getEnclosingBlockScopeContainer(host) || file;
+                currentFlow = { flags: 2 /* Start */ };
+                parent = typeAlias;
+                bind(typeAlias.typeExpression);
+                if (!typeAlias.fullName || typeAlias.fullName.kind === 71 /* Identifier */) {
+                    parent = typeAlias.parent;
+                    bindBlockScopedDeclaration(typeAlias, 524288 /* TypeAlias */, 67901928 /* TypeAliasExcludes */);
+                }
+                else {
+                    bind(typeAlias.fullName);
+                }
+            }
+            container = saveContainer;
+            lastContainer = saveLastContainer;
+            blockScopeContainer = saveBlockScopeContainer;
+            parent = saveParent;
+            currentFlow = saveCurrentFlow;
+        }
+        // The binder visits every node in the syntax tree so it is a convenient place to perform a single localized
+        // check for reserved words used as identifiers in strict mode code.
+        function checkStrictModeIdentifier(node) {
+            if (inStrictMode &&
+                node.originalKeywordKind >= 108 /* FirstFutureReservedWord */ &&
+                node.originalKeywordKind <= 116 /* LastFutureReservedWord */ &&
+                !ts.isIdentifierName(node) &&
+                !(node.flags & 4194304 /* Ambient */)) {
+                // Report error only if there are no parse errors in file
+                if (!file.parseDiagnostics.length) {
+                    file.bindDiagnostics.push(createDiagnosticForNode(node, getStrictModeIdentifierMessage(node), ts.declarationNameToString(node)));
+                }
+            }
+        }
+        function getStrictModeIdentifierMessage(node) {
+            // Provide specialized messages to help the user understand why we think they're in
+            // strict mode.
+            if (ts.getContainingClass(node)) {
+                return ts.Diagnostics.Identifier_expected_0_is_a_reserved_word_in_strict_mode_Class_definitions_are_automatically_in_strict_mode;
+            }
+            if (file.externalModuleIndicator) {
+                return ts.Diagnostics.Identifier_expected_0_is_a_reserved_word_in_strict_mode_Modules_are_automatically_in_strict_mode;
+            }
+            return ts.Diagnostics.Identifier_expected_0_is_a_reserved_word_in_strict_mode;
+        }
+        function checkStrictModeBinaryExpression(node) {
+            if (inStrictMode && ts.isLeftHandSideExpression(node.left) && ts.isAssignmentOperator(node.operatorToken.kind)) {
+                // ECMA 262 (Annex C) The identifier eval or arguments may not appear as the LeftHandSideExpression of an
+                // Assignment operator(11.13) or of a PostfixExpression(11.3)
+                checkStrictModeEvalOrArguments(node, node.left);
+            }
+        }
+        function checkStrictModeCatchClause(node) {
+            // It is a SyntaxError if a TryStatement with a Catch occurs within strict code and the Identifier of the
+            // Catch production is eval or arguments
+            if (inStrictMode && node.variableDeclaration) {
+                checkStrictModeEvalOrArguments(node, node.variableDeclaration.name);
+            }
+        }
+        function checkStrictModeDeleteExpression(node) {
+            // Grammar checking
+            if (inStrictMode && node.expression.kind === 71 /* Identifier */) {
+                // When a delete operator occurs within strict mode code, a SyntaxError is thrown if its
+                // UnaryExpression is a direct reference to a variable, function argument, or function name
+                var span = ts.getErrorSpanForNode(file, node.expression);
+                file.bindDiagnostics.push(ts.createFileDiagnostic(file, span.start, span.length, ts.Diagnostics.delete_cannot_be_called_on_an_identifier_in_strict_mode));
+            }
+        }
+        function isEvalOrArgumentsIdentifier(node) {
+            return ts.isIdentifier(node) && (node.escapedText === "eval" || node.escapedText === "arguments");
+        }
+        function checkStrictModeEvalOrArguments(contextNode, name) {
+            if (name && name.kind === 71 /* Identifier */) {
+                var identifier = name;
+                if (isEvalOrArgumentsIdentifier(identifier)) {
+                    // We check first if the name is inside class declaration or class expression; if so give explicit message
+                    // otherwise report generic error message.
+                    var span = ts.getErrorSpanForNode(file, name);
+                    file.bindDiagnostics.push(ts.createFileDiagnostic(file, span.start, span.length, getStrictModeEvalOrArgumentsMessage(contextNode), ts.idText(identifier)));
+                }
+            }
+        }
+        function getStrictModeEvalOrArgumentsMessage(node) {
+            // Provide specialized messages to help the user understand why we think they're in
+            // strict mode.
+            if (ts.getContainingClass(node)) {
+                return ts.Diagnostics.Invalid_use_of_0_Class_definitions_are_automatically_in_strict_mode;
+            }
+            if (file.externalModuleIndicator) {
+                return ts.Diagnostics.Invalid_use_of_0_Modules_are_automatically_in_strict_mode;
+            }
+            return ts.Diagnostics.Invalid_use_of_0_in_strict_mode;
+        }
+        function checkStrictModeFunctionName(node) {
+            if (inStrictMode) {
+                // It is a SyntaxError if the identifier eval or arguments appears within a FormalParameterList of a strict mode FunctionDeclaration or FunctionExpression (13.1))
+                checkStrictModeEvalOrArguments(node, node.name);
+            }
+        }
+        function getStrictModeBlockScopeFunctionDeclarationMessage(node) {
+            // Provide specialized messages to help the user understand why we think they're in
+            // strict mode.
+            if (ts.getContainingClass(node)) {
+                return ts.Diagnostics.Function_declarations_are_not_allowed_inside_blocks_in_strict_mode_when_targeting_ES3_or_ES5_Class_definitions_are_automatically_in_strict_mode;
+            }
+            if (file.externalModuleIndicator) {
+                return ts.Diagnostics.Function_declarations_are_not_allowed_inside_blocks_in_strict_mode_when_targeting_ES3_or_ES5_Modules_are_automatically_in_strict_mode;
+            }
+            return ts.Diagnostics.Function_declarations_are_not_allowed_inside_blocks_in_strict_mode_when_targeting_ES3_or_ES5;
+        }
+        function checkStrictModeFunctionDeclaration(node) {
+            if (languageVersion < 2 /* ES2015 */) {
+                // Report error if function is not top level function declaration
+                if (blockScopeContainer.kind !== 274 /* SourceFile */ &&
+                    blockScopeContainer.kind !== 239 /* ModuleDeclaration */ &&
+                    !ts.isFunctionLike(blockScopeContainer)) {
+                    // We check first if the name is inside class declaration or class expression; if so give explicit message
+                    // otherwise report generic error message.
+                    var errorSpan = ts.getErrorSpanForNode(file, node);
+                    file.bindDiagnostics.push(ts.createFileDiagnostic(file, errorSpan.start, errorSpan.length, getStrictModeBlockScopeFunctionDeclarationMessage(node)));
+                }
+            }
+        }
+        function checkStrictModeNumericLiteral(node) {
+            if (inStrictMode && node.numericLiteralFlags & 32 /* Octal */) {
+                file.bindDiagnostics.push(createDiagnosticForNode(node, ts.Diagnostics.Octal_literals_are_not_allowed_in_strict_mode));
+            }
+        }
+        function checkStrictModePostfixUnaryExpression(node) {
+            // Grammar checking
+            // The identifier eval or arguments may not appear as the LeftHandSideExpression of an
+            // Assignment operator(11.13) or of a PostfixExpression(11.3) or as the UnaryExpression
+            // operated upon by a Prefix Increment(11.4.4) or a Prefix Decrement(11.4.5) operator.
+            if (inStrictMode) {
+                checkStrictModeEvalOrArguments(node, node.operand);
+            }
+        }
+        function checkStrictModePrefixUnaryExpression(node) {
+            // Grammar checking
+            if (inStrictMode) {
+                if (node.operator === 43 /* PlusPlusToken */ || node.operator === 44 /* MinusMinusToken */) {
+                    checkStrictModeEvalOrArguments(node, node.operand);
+                }
+            }
+        }
+        function checkStrictModeWithStatement(node) {
+            // Grammar checking for withStatement
+            if (inStrictMode) {
+                errorOnFirstToken(node, ts.Diagnostics.with_statements_are_not_allowed_in_strict_mode);
+            }
+        }
+        function errorOnFirstToken(node, message, arg0, arg1, arg2) {
+            var span = ts.getSpanOfTokenAtPosition(file, node.pos);
+            file.bindDiagnostics.push(ts.createFileDiagnostic(file, span.start, span.length, message, arg0, arg1, arg2));
+        }
+        function errorOrSuggestionOnFirstToken(isError, node, message, arg0, arg1, arg2) {
+            var span = ts.getSpanOfTokenAtPosition(file, node.pos);
+            var diag = ts.createFileDiagnostic(file, span.start, span.length, message, arg0, arg1, arg2);
+            if (isError) {
+                file.bindDiagnostics.push(diag);
+            }
+            else {
+                file.bindSuggestionDiagnostics = ts.append(file.bindSuggestionDiagnostics, __assign({}, diag, { category: ts.DiagnosticCategory.Suggestion }));
+            }
+        }
+        function bind(node) {
+            if (!node) {
+                return;
+            }
+            node.parent = parent;
+            var saveInStrictMode = inStrictMode;
+            // Even though in the AST the jsdoc @typedef node belongs to the current node,
+            // its symbol might be in the same scope with the current node's symbol. Consider:
+            //
+            //     /** @typedef {string | number} MyType */
+            //     function foo();
+            //
+            // Here the current node is "foo", which is a container, but the scope of "MyType" should
+            // not be inside "foo". Therefore we always bind @typedef before bind the parent node,
+            // and skip binding this tag later when binding all the other jsdoc tags.
+            // First we bind declaration nodes to a symbol if possible. We'll both create a symbol
+            // and then potentially add the symbol to an appropriate symbol table. Possible
+            // destination symbol tables are:
+            //
+            //  1) The 'exports' table of the current container's symbol.
+            //  2) The 'members' table of the current container's symbol.
+            //  3) The 'locals' table of the current container.
+            //
+            // However, not all symbols will end up in any of these tables. 'Anonymous' symbols
+            // (like TypeLiterals for example) will not be put in any table.
+            bindWorker(node);
+            // Then we recurse into the children of the node to bind them as well. For certain
+            // symbols we do specialized work when we recurse. For example, we'll keep track of
+            // the current 'container' node when it changes. This helps us know which symbol table
+            // a local should go into for example. Since terminal nodes are known not to have
+            // children, as an optimization we don't process those.
+            if (node.kind > 145 /* LastToken */) {
+                var saveParent = parent;
+                parent = node;
+                var containerFlags = getContainerFlags(node);
+                if (containerFlags === 0 /* None */) {
+                    bindChildren(node);
+                }
+                else {
+                    bindContainer(node, containerFlags);
+                }
+                parent = saveParent;
+            }
+            else if (!skipTransformFlagAggregation && (node.transformFlags & 536870912 /* HasComputedFlags */) === 0) {
+                subtreeTransformFlags |= computeTransformFlagsForNode(node, 0);
+                bindJSDoc(node);
+            }
+            inStrictMode = saveInStrictMode;
+        }
+        function bindJSDoc(node) {
+            if (ts.hasJSDocNodes(node)) {
+                if (ts.isInJavaScriptFile(node)) {
+                    for (var _i = 0, _a = node.jsDoc; _i < _a.length; _i++) {
+                        var j = _a[_i];
+                        bind(j);
+                    }
+                }
+                else {
+                    for (var _b = 0, _c = node.jsDoc; _b < _c.length; _b++) {
+                        var j = _c[_b];
+                        setParentPointers(node, j);
+                    }
+                }
+            }
+        }
+        function updateStrictModeStatementList(statements) {
+            if (!inStrictMode) {
+                for (var _i = 0, statements_1 = statements; _i < statements_1.length; _i++) {
+                    var statement = statements_1[_i];
+                    if (!ts.isPrologueDirective(statement)) {
+                        return;
+                    }
+                    if (isUseStrictPrologueDirective(statement)) {
+                        inStrictMode = true;
+                        return;
+                    }
+                }
+            }
+        }
+        /// Should be called only on prologue directives (isPrologueDirective(node) should be true)
+        function isUseStrictPrologueDirective(node) {
+            var nodeText = ts.getSourceTextOfNodeFromSourceFile(file, node.expression);
+            // Note: the node text must be exactly "use strict" or 'use strict'.  It is not ok for the
+            // string to contain unicode escapes (as per ES5).
+            return nodeText === '"use strict"' || nodeText === "'use strict'";
+        }
+        function bindWorker(node) {
+            switch (node.kind) {
+                /* Strict mode checks */
+                case 71 /* Identifier */:
+                    // for typedef type names with namespaces, bind the new jsdoc type symbol here
+                    // because it requires all containing namespaces to be in effect, namely the
+                    // current "blockScopeContainer" needs to be set to its immediate namespace parent.
+                    if (node.isInJSDocNamespace) {
+                        var parentNode = node.parent;
+                        while (parentNode && !ts.isJSDocTypeAlias(parentNode)) {
+                            parentNode = parentNode.parent;
+                        }
+                        bindBlockScopedDeclaration(parentNode, 524288 /* TypeAlias */, 67901928 /* TypeAliasExcludes */);
+                        break;
+                    }
+                // falls through
+                case 99 /* ThisKeyword */:
+                    if (currentFlow && (ts.isExpression(node) || parent.kind === 271 /* ShorthandPropertyAssignment */)) {
+                        node.flowNode = currentFlow;
+                    }
+                    return checkStrictModeIdentifier(node);
+                case 185 /* PropertyAccessExpression */:
+                    if (currentFlow && isNarrowableReference(node)) {
+                        node.flowNode = currentFlow;
+                    }
+                    if (ts.isSpecialPropertyDeclaration(node)) {
+                        bindSpecialPropertyDeclaration(node);
+                    }
+                    break;
+                case 200 /* BinaryExpression */:
+                    var specialKind = ts.getSpecialPropertyAssignmentKind(node);
+                    switch (specialKind) {
+                        case 1 /* ExportsProperty */:
+                            bindExportsPropertyAssignment(node);
+                            break;
+                        case 2 /* ModuleExports */:
+                            bindModuleExportsAssignment(node);
+                            break;
+                        case 3 /* PrototypeProperty */:
+                            bindPrototypePropertyAssignment(node.left, node);
+                            break;
+                        case 6 /* Prototype */:
+                            bindPrototypeAssignment(node);
+                            break;
+                        case 4 /* ThisProperty */:
+                            bindThisPropertyAssignment(node);
+                            break;
+                        case 5 /* Property */:
+                            bindSpecialPropertyAssignment(node);
+                            break;
+                        case 0 /* None */:
+                            // Nothing to do
+                            break;
+                        default:
+                            ts.Debug.fail("Unknown special property assignment kind");
+                    }
+                    return checkStrictModeBinaryExpression(node);
+                case 269 /* CatchClause */:
+                    return checkStrictModeCatchClause(node);
+                case 194 /* DeleteExpression */:
+                    return checkStrictModeDeleteExpression(node);
+                case 8 /* NumericLiteral */:
+                    return checkStrictModeNumericLiteral(node);
+                case 199 /* PostfixUnaryExpression */:
+                    return checkStrictModePostfixUnaryExpression(node);
+                case 198 /* PrefixUnaryExpression */:
+                    return checkStrictModePrefixUnaryExpression(node);
+                case 226 /* WithStatement */:
+                    return checkStrictModeWithStatement(node);
+                case 174 /* ThisType */:
+                    seenThisKeyword = true;
+                    return;
+                case 161 /* TypePredicate */:
+                    break; // Binding the children will handle everything
+                case 148 /* TypeParameter */:
+                    return bindTypeParameter(node);
+                case 149 /* Parameter */:
+                    return bindParameter(node);
+                case 232 /* VariableDeclaration */:
+                    return bindVariableDeclarationOrBindingElement(node);
+                case 182 /* BindingElement */:
+                    node.flowNode = currentFlow;
+                    return bindVariableDeclarationOrBindingElement(node);
+                case 152 /* PropertyDeclaration */:
+                case 151 /* PropertySignature */:
+                    return bindPropertyWorker(node);
+                case 270 /* PropertyAssignment */:
+                case 271 /* ShorthandPropertyAssignment */:
+                    return bindPropertyOrMethodOrAccessor(node, 4 /* Property */, 0 /* PropertyExcludes */);
+                case 273 /* EnumMember */:
+                    return bindPropertyOrMethodOrAccessor(node, 8 /* EnumMember */, 68008959 /* EnumMemberExcludes */);
+                case 158 /* CallSignature */:
+                case 159 /* ConstructSignature */:
+                case 160 /* IndexSignature */:
+                    return declareSymbolAndAddToSymbolTable(node, 131072 /* Signature */, 0 /* None */);
+                case 154 /* MethodDeclaration */:
+                case 153 /* MethodSignature */:
+                    // If this is an ObjectLiteralExpression method, then it sits in the same space
+                    // as other properties in the object literal.  So we use SymbolFlags.PropertyExcludes
+                    // so that it will conflict with any other object literal members with the same
+                    // name.
+                    return bindPropertyOrMethodOrAccessor(node, 8192 /* Method */ | (node.questionToken ? 16777216 /* Optional */ : 0 /* None */), ts.isObjectLiteralMethod(node) ? 0 /* PropertyExcludes */ : 67208127 /* MethodExcludes */);
+                case 234 /* FunctionDeclaration */:
+                    return bindFunctionDeclaration(node);
+                case 155 /* Constructor */:
+                    return declareSymbolAndAddToSymbolTable(node, 16384 /* Constructor */, /*symbolExcludes:*/ 0 /* None */);
+                case 156 /* GetAccessor */:
+                    return bindPropertyOrMethodOrAccessor(node, 32768 /* GetAccessor */, 67150783 /* GetAccessorExcludes */);
+                case 157 /* SetAccessor */:
+                    return bindPropertyOrMethodOrAccessor(node, 65536 /* SetAccessor */, 67183551 /* SetAccessorExcludes */);
+                case 163 /* FunctionType */:
+                case 284 /* JSDocFunctionType */:
+                case 288 /* JSDocSignature */:
+                case 164 /* ConstructorType */:
+                    return bindFunctionOrConstructorType(node);
+                case 166 /* TypeLiteral */:
+                case 287 /* JSDocTypeLiteral */:
+                case 177 /* MappedType */:
+                    return bindAnonymousTypeWorker(node);
+                case 184 /* ObjectLiteralExpression */:
+                    return bindObjectLiteralExpression(node);
+                case 192 /* FunctionExpression */:
+                case 193 /* ArrowFunction */:
+                    return bindFunctionExpression(node);
+                case 187 /* CallExpression */:
+                    if (ts.isInJavaScriptFile(node)) {
+                        bindCallExpression(node);
+                    }
+                    break;
+                // Members of classes, interfaces, and modules
+                case 205 /* ClassExpression */:
+                case 235 /* ClassDeclaration */:
+                    // All classes are automatically in strict mode in ES6.
+                    inStrictMode = true;
+                    return bindClassLikeDeclaration(node);
+                case 236 /* InterfaceDeclaration */:
+                    return bindBlockScopedDeclaration(node, 64 /* Interface */, 67901832 /* InterfaceExcludes */);
+                case 237 /* TypeAliasDeclaration */:
+                    return bindBlockScopedDeclaration(node, 524288 /* TypeAlias */, 67901928 /* TypeAliasExcludes */);
+                case 238 /* EnumDeclaration */:
+                    return bindEnumDeclaration(node);
+                case 239 /* ModuleDeclaration */:
+                    return bindModuleDeclaration(node);
+                // Jsx-attributes
+                case 263 /* JsxAttributes */:
+                    return bindJsxAttributes(node);
+                case 262 /* JsxAttribute */:
+                    return bindJsxAttribute(node, 4 /* Property */, 0 /* PropertyExcludes */);
+                // Imports and exports
+                case 243 /* ImportEqualsDeclaration */:
+                case 246 /* NamespaceImport */:
+                case 248 /* ImportSpecifier */:
+                case 252 /* ExportSpecifier */:
+                    return declareSymbolAndAddToSymbolTable(node, 2097152 /* Alias */, 2097152 /* AliasExcludes */);
+                case 242 /* NamespaceExportDeclaration */:
+                    return bindNamespaceExportDeclaration(node);
+                case 245 /* ImportClause */:
+                    return bindImportClause(node);
+                case 250 /* ExportDeclaration */:
+                    return bindExportDeclaration(node);
+                case 249 /* ExportAssignment */:
+                    return bindExportAssignment(node);
+                case 274 /* SourceFile */:
+                    updateStrictModeStatementList(node.statements);
+                    return bindSourceFileIfExternalModule();
+                case 213 /* Block */:
+                    if (!ts.isFunctionLike(node.parent)) {
+                        return;
+                    }
+                // falls through
+                case 240 /* ModuleBlock */:
+                    return updateStrictModeStatementList(node.statements);
+                case 293 /* JSDocParameterTag */:
+                    if (node.parent.kind === 288 /* JSDocSignature */) {
+                        return bindParameter(node);
+                    }
+                    if (node.parent.kind !== 287 /* JSDocTypeLiteral */) {
+                        break;
+                    }
+                // falls through
+                case 298 /* JSDocPropertyTag */:
+                    var propTag = node;
+                    var flags = propTag.isBracketed || propTag.typeExpression && propTag.typeExpression.type.kind === 283 /* JSDocOptionalType */ ?
+                        4 /* Property */ | 16777216 /* Optional */ :
+                        4 /* Property */;
+                    return declareSymbolAndAddToSymbolTable(propTag, flags, 0 /* PropertyExcludes */);
+                case 297 /* JSDocTypedefTag */:
+                case 292 /* JSDocCallbackTag */:
+                    return (delayedTypeAliases || (delayedTypeAliases = [])).push(node);
+            }
+        }
+        function bindPropertyWorker(node) {
+            return bindPropertyOrMethodOrAccessor(node, 4 /* Property */ | (node.questionToken ? 16777216 /* Optional */ : 0 /* None */), 0 /* PropertyExcludes */);
+        }
+        function bindAnonymousTypeWorker(node) {
+            return bindAnonymousDeclaration(node, 2048 /* TypeLiteral */, "__type" /* Type */);
+        }
+        function bindSourceFileIfExternalModule() {
+            setExportContextFlag(file);
+            if (ts.isExternalModule(file)) {
+                bindSourceFileAsExternalModule();
+            }
+            else if (ts.isJsonSourceFile(file)) {
+                bindSourceFileAsExternalModule();
+                // Create symbol equivalent for the module.exports = {}
+                var originalSymbol = file.symbol;
+                declareSymbol(file.symbol.exports, file.symbol, file, 4 /* Property */, 67108863 /* All */);
+                file.symbol = originalSymbol;
+            }
+        }
+        function bindSourceFileAsExternalModule() {
+            bindAnonymousDeclaration(file, 512 /* ValueModule */, "\"" + ts.removeFileExtension(file.fileName) + "\"");
+        }
+        function bindExportAssignment(node) {
+            if (!container.symbol || !container.symbol.exports) {
+                // Export assignment in some sort of block construct
+                bindAnonymousDeclaration(node, 2097152 /* Alias */, getDeclarationName(node));
+            }
+            else {
+                var flags = node.kind === 249 /* ExportAssignment */ && ts.exportAssignmentIsAlias(node)
+                    // An export default clause with an EntityNameExpression or a class expression exports all meanings of that identifier or expression;
+                    ? 2097152 /* Alias */
+                    // An export default clause with any other expression exports a value
+                    : 4 /* Property */;
+                // If there is an `export default x;` alias declaration, can't `export default` anything else.
+                // (In contrast, you can still have `export default function f() {}` and `export default interface I {}`.)
+                declareSymbol(container.symbol.exports, container.symbol, node, flags, 67108863 /* All */);
+            }
+        }
+        function bindNamespaceExportDeclaration(node) {
+            if (node.modifiers && node.modifiers.length) {
+                file.bindDiagnostics.push(createDiagnosticForNode(node, ts.Diagnostics.Modifiers_cannot_appear_here));
+            }
+            if (node.parent.kind !== 274 /* SourceFile */) {
+                file.bindDiagnostics.push(createDiagnosticForNode(node, ts.Diagnostics.Global_module_exports_may_only_appear_at_top_level));
+                return;
+            }
+            else {
+                var parent_1 = node.parent;
+                if (!ts.isExternalModule(parent_1)) {
+                    file.bindDiagnostics.push(createDiagnosticForNode(node, ts.Diagnostics.Global_module_exports_may_only_appear_in_module_files));
+                    return;
+                }
+                if (!parent_1.isDeclarationFile) {
+                    file.bindDiagnostics.push(createDiagnosticForNode(node, ts.Diagnostics.Global_module_exports_may_only_appear_in_declaration_files));
+                    return;
+                }
+            }
+            file.symbol.globalExports = file.symbol.globalExports || ts.createSymbolTable();
+            declareSymbol(file.symbol.globalExports, file.symbol, node, 2097152 /* Alias */, 2097152 /* AliasExcludes */);
+        }
+        function bindExportDeclaration(node) {
+            if (!container.symbol || !container.symbol.exports) {
+                // Export * in some sort of block construct
+                bindAnonymousDeclaration(node, 8388608 /* ExportStar */, getDeclarationName(node));
+            }
+            else if (!node.exportClause) {
+                // All export * declarations are collected in an __export symbol
+                declareSymbol(container.symbol.exports, container.symbol, node, 8388608 /* ExportStar */, 0 /* None */);
+            }
+        }
+        function bindImportClause(node) {
+            if (node.name) {
+                declareSymbolAndAddToSymbolTable(node, 2097152 /* Alias */, 2097152 /* AliasExcludes */);
+            }
+        }
+        function setCommonJsModuleIndicator(node) {
+            if (!file.commonJsModuleIndicator) {
+                file.commonJsModuleIndicator = node;
+                if (!file.externalModuleIndicator) {
+                    bindSourceFileAsExternalModule();
+                }
+            }
+        }
+        function bindExportsPropertyAssignment(node) {
+            // When we create a property via 'exports.foo = bar', the 'exports.foo' property access
+            // expression is the declaration
+            setCommonJsModuleIndicator(node);
+            var lhs = node.left;
+            var symbol = forEachIdentifierInEntityName(lhs.expression, /*parent*/ undefined, function (id, symbol) {
+                if (symbol) {
+                    addDeclarationToSymbol(symbol, id, 1536 /* Module */ | 67108864 /* JSContainer */);
+                }
+                return symbol;
+            });
+            if (symbol) {
+                var flags = ts.isClassExpression(node.right) ?
+                    4 /* Property */ | 1048576 /* ExportValue */ | 32 /* Class */ :
+                    4 /* Property */ | 1048576 /* ExportValue */;
+                declareSymbol(symbol.exports, symbol, lhs, flags, 0 /* None */);
+            }
+        }
+        function bindModuleExportsAssignment(node) {
+            // A common practice in node modules is to set 'export = module.exports = {}', this ensures that 'exports'
+            // is still pointing to 'module.exports'.
+            // We do not want to consider this as 'export=' since a module can have only one of these.
+            // Similarly we do not want to treat 'module.exports = exports' as an 'export='.
+            var assignedExpression = ts.getRightMostAssignedExpression(node.right);
+            if (ts.isEmptyObjectLiteral(assignedExpression) || container === file && isExportsOrModuleExportsOrAlias(file, assignedExpression)) {
+                // Mark it as a module in case there are no other exports in the file
+                setCommonJsModuleIndicator(node);
+                return;
+            }
+            // 'module.exports = expr' assignment
+            setCommonJsModuleIndicator(node);
+            var flags = ts.exportAssignmentIsAlias(node)
+                ? 2097152 /* Alias */
+                : 4 /* Property */ | 1048576 /* ExportValue */ | 512 /* ValueModule */;
+            declareSymbol(file.symbol.exports, file.symbol, node, flags, 0 /* None */);
+        }
+        function bindThisPropertyAssignment(node) {
+            ts.Debug.assert(ts.isInJavaScriptFile(node));
+            var thisContainer = ts.getThisContainer(node, /*includeArrowFunctions*/ false);
+            switch (thisContainer.kind) {
+                case 234 /* FunctionDeclaration */:
+                case 192 /* FunctionExpression */:
+                    var constructorSymbol = thisContainer.symbol;
+                    // For `f.prototype.m = function() { this.x = 0; }`, `this.x = 0` should modify `f`'s members, not the function expression.
+                    if (ts.isBinaryExpression(thisContainer.parent) && thisContainer.parent.operatorToken.kind === 58 /* EqualsToken */) {
+                        var l = thisContainer.parent.left;
+                        if (ts.isPropertyAccessEntityNameExpression(l) && ts.isPrototypeAccess(l.expression)) {
+                            constructorSymbol = lookupSymbolForPropertyAccess(l.expression.expression, thisParentContainer);
+                        }
+                    }
+                    if (constructorSymbol) {
+                        // Declare a 'member' if the container is an ES5 class or ES6 constructor
+                        constructorSymbol.members = constructorSymbol.members || ts.createSymbolTable();
+                        // It's acceptable for multiple 'this' assignments of the same identifier to occur
+                        declareSymbol(constructorSymbol.members, constructorSymbol, node, 4 /* Property */, 0 /* PropertyExcludes */ & ~4 /* Property */);
+                    }
+                    break;
+                case 155 /* Constructor */:
+                case 152 /* PropertyDeclaration */:
+                case 154 /* MethodDeclaration */:
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                    // this.foo assignment in a JavaScript class
+                    // Bind this property to the containing class
+                    var containingClass = thisContainer.parent;
+                    var symbolTable = ts.hasModifier(thisContainer, 32 /* Static */) ? containingClass.symbol.exports : containingClass.symbol.members;
+                    declareSymbol(symbolTable, containingClass.symbol, node, 4 /* Property */, 0 /* None */, /*isReplaceableByMethod*/ true);
+                    break;
+                case 274 /* SourceFile */:
+                    // this.foo assignment in a source file
+                    // Do not bind. It would be nice to support this someday though.
+                    break;
+                default:
+                    ts.Debug.fail(ts.Debug.showSyntaxKind(thisContainer));
+            }
+        }
+        function bindSpecialPropertyDeclaration(node) {
+            if (node.expression.kind === 99 /* ThisKeyword */) {
+                bindThisPropertyAssignment(node);
+            }
+            else if (ts.isPropertyAccessEntityNameExpression(node) && node.parent.parent.kind === 274 /* SourceFile */) {
+                if (ts.isPrototypeAccess(node.expression)) {
+                    bindPrototypePropertyAssignment(node, node.parent);
+                }
+                else {
+                    bindStaticPropertyAssignment(node);
+                }
+            }
+        }
+        /** For `x.prototype = { p, ... }`, declare members p,... if `x` is function/class/{}, or not declared. */
+        function bindPrototypeAssignment(node) {
+            node.left.parent = node;
+            node.right.parent = node;
+            var lhs = node.left;
+            bindPropertyAssignment(lhs, lhs, /*isPrototypeProperty*/ false);
+        }
+        /**
+         * For `x.prototype.y = z`, declare a member `y` on `x` if `x` is a function or class, or not declared.
+         * Note that jsdoc preceding an ExpressionStatement like `x.prototype.y;` is also treated as a declaration.
+         */
+        function bindPrototypePropertyAssignment(lhs, parent) {
+            // Look up the function in the local scope, since prototype assignments should
+            // follow the function declaration
+            var classPrototype = lhs.expression;
+            var constructorFunction = classPrototype.expression;
+            // Fix up parent pointers since we're going to use these nodes before we bind into them
+            lhs.parent = parent;
+            constructorFunction.parent = classPrototype;
+            classPrototype.parent = lhs;
+            bindPropertyAssignment(constructorFunction, lhs, /*isPrototypeProperty*/ true);
+        }
+        function bindSpecialPropertyAssignment(node) {
+            var lhs = node.left;
+            // Fix up parent pointers since we're going to use these nodes before we bind into them
+            node.left.parent = node;
+            node.right.parent = node;
+            if (ts.isIdentifier(lhs.expression) && container === file && isNameOfExportsOrModuleExportsAliasDeclaration(file, lhs.expression)) {
+                // This can be an alias for the 'exports' or 'module.exports' names, e.g.
+                //    var util = module.exports;
+                //    util.property = function ...
+                bindExportsPropertyAssignment(node);
+            }
+            else {
+                bindStaticPropertyAssignment(lhs);
+            }
+        }
+        /**
+         * For nodes like `x.y = z`, declare a member 'y' on 'x' if x is a function (or IIFE) or class or {}, or not declared.
+         * Also works for expression statements preceded by JSDoc, like / ** @type number * / x.y;
+         */
+        function bindStaticPropertyAssignment(node) {
+            node.expression.parent = node;
+            bindPropertyAssignment(node.expression, node, /*isPrototypeProperty*/ false);
+        }
+        function bindPropertyAssignment(name, propertyAccess, isPrototypeProperty) {
+            var namespaceSymbol = lookupSymbolForPropertyAccess(name);
+            var isToplevelNamespaceableInitializer = ts.isBinaryExpression(propertyAccess.parent)
+                ? getParentOfBinaryExpression(propertyAccess.parent).parent.kind === 274 /* SourceFile */ &&
+                    !!ts.getJavascriptInitializer(ts.getInitializerOfBinaryExpression(propertyAccess.parent), ts.isPrototypeAccess(propertyAccess.parent.left))
+                : propertyAccess.parent.parent.kind === 274 /* SourceFile */;
+            if (!isPrototypeProperty && (!namespaceSymbol || !(namespaceSymbol.flags & 1920 /* Namespace */)) && isToplevelNamespaceableInitializer) {
+                // make symbols or add declarations for intermediate containers
+                var flags_1 = 1536 /* Module */ | 67108864 /* JSContainer */;
+                var excludeFlags_1 = 67215503 /* ValueModuleExcludes */ & ~67108864 /* JSContainer */;
+                namespaceSymbol = forEachIdentifierInEntityName(propertyAccess.expression, namespaceSymbol, function (id, symbol, parent) {
+                    if (symbol) {
+                        addDeclarationToSymbol(symbol, id, flags_1);
+                        return symbol;
+                    }
+                    else {
+                        return declareSymbol(parent ? parent.exports : container.locals, parent, id, flags_1, excludeFlags_1);
+                    }
+                });
+            }
+            if (!namespaceSymbol || !isJavascriptContainer(namespaceSymbol)) {
+                return;
+            }
+            // Set up the members collection if it doesn't exist already
+            var symbolTable = isPrototypeProperty ?
+                (namespaceSymbol.members || (namespaceSymbol.members = ts.createSymbolTable())) :
+                (namespaceSymbol.exports || (namespaceSymbol.exports = ts.createSymbolTable()));
+            // Declare the method/property
+            var jsContainerFlag = isToplevelNamespaceableInitializer ? 67108864 /* JSContainer */ : 0;
+            var isMethod = ts.isFunctionLikeDeclaration(ts.getAssignedJavascriptInitializer(propertyAccess));
+            var symbolFlags = (isMethod ? 8192 /* Method */ : 4 /* Property */) | jsContainerFlag;
+            var symbolExcludes = (isMethod ? 67208127 /* MethodExcludes */ : 0 /* PropertyExcludes */) & ~jsContainerFlag;
+            declareSymbol(symbolTable, namespaceSymbol, propertyAccess, symbolFlags, symbolExcludes);
+        }
+        /**
+         * Javascript containers are:
+         * - Functions
+         * - classes
+         * - namespaces
+         * - variables initialized with function expressions
+         * -                       with class expressions
+         * -                       with empty object literals
+         * -                       with non-empty object literals if assigned to the prototype property
+         */
+        function isJavascriptContainer(symbol) {
+            if (symbol.flags & (16 /* Function */ | 32 /* Class */ | 1024 /* NamespaceModule */)) {
+                return true;
+            }
+            var node = symbol.valueDeclaration;
+            var init = !node ? undefined :
+                ts.isVariableDeclaration(node) ? node.initializer :
+                    ts.isBinaryExpression(node) ? node.right :
+                        ts.isPropertyAccessExpression(node) && ts.isBinaryExpression(node.parent) ? node.parent.right :
+                            undefined;
+            if (init) {
+                var isPrototypeAssignment = ts.isPrototypeAccess(ts.isVariableDeclaration(node) ? node.name : ts.isBinaryExpression(node) ? node.left : node);
+                return !!ts.getJavascriptInitializer(ts.isBinaryExpression(init) && init.operatorToken.kind === 54 /* BarBarToken */ ? init.right : init, isPrototypeAssignment);
+            }
+            return false;
+        }
+        function getParentOfBinaryExpression(expr) {
+            while (ts.isBinaryExpression(expr.parent)) {
+                expr = expr.parent;
+            }
+            return expr.parent;
+        }
+        function lookupSymbolForPropertyAccess(node, lookupContainer) {
+            if (lookupContainer === void 0) { lookupContainer = container; }
+            if (ts.isIdentifier(node)) {
+                return lookupSymbolForNameWorker(lookupContainer, node.escapedText);
+            }
+            else {
+                var symbol = lookupSymbolForPropertyAccess(node.expression);
+                return symbol && symbol.exports && symbol.exports.get(node.name.escapedText);
+            }
+        }
+        function forEachIdentifierInEntityName(e, parent, action) {
+            if (isExportsOrModuleExportsOrAlias(file, e)) {
+                return file.symbol;
+            }
+            else if (ts.isIdentifier(e)) {
+                return action(e, lookupSymbolForPropertyAccess(e), parent);
+            }
+            else {
+                var s = forEachIdentifierInEntityName(e.expression, parent, action);
+                if (!s || !s.exports)
+                    return ts.Debug.fail();
+                return action(e.name, s.exports.get(e.name.escapedText), s);
+            }
+        }
+        function bindCallExpression(node) {
+            // We're only inspecting call expressions to detect CommonJS modules, so we can skip
+            // this check if we've already seen the module indicator
+            if (!file.commonJsModuleIndicator && ts.isRequireCall(node, /*checkArgumentIsStringLiteralLike*/ false)) {
+                setCommonJsModuleIndicator(node);
+            }
+        }
+        function bindClassLikeDeclaration(node) {
+            if (node.kind === 235 /* ClassDeclaration */) {
+                bindBlockScopedDeclaration(node, 32 /* Class */, 68008383 /* ClassExcludes */);
+            }
+            else {
+                var bindingName = node.name ? node.name.escapedText : "__class" /* Class */;
+                bindAnonymousDeclaration(node, 32 /* Class */, bindingName);
+                // Add name of class expression into the map for semantic classifier
+                if (node.name) {
+                    classifiableNames.set(node.name.escapedText, true);
+                }
+            }
+            var symbol = node.symbol;
+            // TypeScript 1.0 spec (April 2014): 8.4
+            // Every class automatically contains a static property member named 'prototype', the
+            // type of which is an instantiation of the class type with type Any supplied as a type
+            // argument for each type parameter. It is an error to explicitly declare a static
+            // property member with the name 'prototype'.
+            //
+            // Note: we check for this here because this class may be merging into a module.  The
+            // module might have an exported variable called 'prototype'.  We can't allow that as
+            // that would clash with the built-in 'prototype' for the class.
+            var prototypeSymbol = createSymbol(4 /* Property */ | 4194304 /* Prototype */, "prototype");
+            var symbolExport = symbol.exports.get(prototypeSymbol.escapedName);
+            if (symbolExport) {
+                if (node.name) {
+                    node.name.parent = node;
+                }
+                file.bindDiagnostics.push(createDiagnosticForNode(symbolExport.declarations[0], ts.Diagnostics.Duplicate_identifier_0, ts.symbolName(prototypeSymbol)));
+            }
+            symbol.exports.set(prototypeSymbol.escapedName, prototypeSymbol);
+            prototypeSymbol.parent = symbol;
+        }
+        function bindEnumDeclaration(node) {
+            return ts.isConst(node)
+                ? bindBlockScopedDeclaration(node, 128 /* ConstEnum */, 68008831 /* ConstEnumExcludes */)
+                : bindBlockScopedDeclaration(node, 256 /* RegularEnum */, 68008191 /* RegularEnumExcludes */);
+        }
+        function bindVariableDeclarationOrBindingElement(node) {
+            if (inStrictMode) {
+                checkStrictModeEvalOrArguments(node, node.name);
+            }
+            if (!ts.isBindingPattern(node.name)) {
+                if (ts.isBlockOrCatchScoped(node)) {
+                    bindBlockScopedVariableDeclaration(node);
+                }
+                else if (ts.isParameterDeclaration(node)) {
+                    // It is safe to walk up parent chain to find whether the node is a destructuring parameter declaration
+                    // because its parent chain has already been set up, since parents are set before descending into children.
+                    //
+                    // If node is a binding element in parameter declaration, we need to use ParameterExcludes.
+                    // Using ParameterExcludes flag allows the compiler to report an error on duplicate identifiers in Parameter Declaration
+                    // For example:
+                    //      function foo([a,a]) {} // Duplicate Identifier error
+                    //      function bar(a,a) {}   // Duplicate Identifier error, parameter declaration in this case is handled in bindParameter
+                    //                             // which correctly set excluded symbols
+                    declareSymbolAndAddToSymbolTable(node, 1 /* FunctionScopedVariable */, 67216319 /* ParameterExcludes */);
+                }
+                else {
+                    declareSymbolAndAddToSymbolTable(node, 1 /* FunctionScopedVariable */, 67216318 /* FunctionScopedVariableExcludes */);
+                }
+            }
+        }
+        function bindParameter(node) {
+            if (node.kind === 293 /* JSDocParameterTag */ && container.kind !== 288 /* JSDocSignature */) {
+                return;
+            }
+            if (inStrictMode && !(node.flags & 4194304 /* Ambient */)) {
+                // It is a SyntaxError if the identifier eval or arguments appears within a FormalParameterList of a
+                // strict mode FunctionLikeDeclaration or FunctionExpression(13.1)
+                checkStrictModeEvalOrArguments(node, node.name);
+            }
+            if (ts.isBindingPattern(node.name)) {
+                bindAnonymousDeclaration(node, 1 /* FunctionScopedVariable */, "__" + node.parent.parameters.indexOf(node));
+            }
+            else {
+                declareSymbolAndAddToSymbolTable(node, 1 /* FunctionScopedVariable */, 67216319 /* ParameterExcludes */);
+            }
+            // If this is a property-parameter, then also declare the property symbol into the
+            // containing class.
+            if (ts.isParameterPropertyDeclaration(node)) {
+                var classDeclaration = node.parent.parent;
+                declareSymbol(classDeclaration.symbol.members, classDeclaration.symbol, node, 4 /* Property */ | (node.questionToken ? 16777216 /* Optional */ : 0 /* None */), 0 /* PropertyExcludes */);
+            }
+        }
+        function bindFunctionDeclaration(node) {
+            if (!file.isDeclarationFile && !(node.flags & 4194304 /* Ambient */)) {
+                if (ts.isAsyncFunction(node)) {
+                    emitFlags |= 1024 /* HasAsyncFunctions */;
+                }
+            }
+            checkStrictModeFunctionName(node);
+            if (inStrictMode) {
+                checkStrictModeFunctionDeclaration(node);
+                bindBlockScopedDeclaration(node, 16 /* Function */, 67215791 /* FunctionExcludes */);
+            }
+            else {
+                declareSymbolAndAddToSymbolTable(node, 16 /* Function */, 67215791 /* FunctionExcludes */);
+            }
+        }
+        function bindFunctionExpression(node) {
+            if (!file.isDeclarationFile && !(node.flags & 4194304 /* Ambient */)) {
+                if (ts.isAsyncFunction(node)) {
+                    emitFlags |= 1024 /* HasAsyncFunctions */;
+                }
+            }
+            if (currentFlow) {
+                node.flowNode = currentFlow;
+            }
+            checkStrictModeFunctionName(node);
+            var bindingName = node.name ? node.name.escapedText : "__function" /* Function */;
+            return bindAnonymousDeclaration(node, 16 /* Function */, bindingName);
+        }
+        function bindPropertyOrMethodOrAccessor(node, symbolFlags, symbolExcludes) {
+            if (!file.isDeclarationFile && !(node.flags & 4194304 /* Ambient */) && ts.isAsyncFunction(node)) {
+                emitFlags |= 1024 /* HasAsyncFunctions */;
+            }
+            if (currentFlow && ts.isObjectLiteralOrClassExpressionMethod(node)) {
+                node.flowNode = currentFlow;
+            }
+            return ts.hasDynamicName(node)
+                ? bindAnonymousDeclaration(node, symbolFlags, "__computed" /* Computed */)
+                : declareSymbolAndAddToSymbolTable(node, symbolFlags, symbolExcludes);
+        }
+        function getInferTypeContainer(node) {
+            var extendsType = ts.findAncestor(node, function (n) { return n.parent && ts.isConditionalTypeNode(n.parent) && n.parent.extendsType === n; });
+            return extendsType && extendsType.parent;
+        }
+        function bindTypeParameter(node) {
+            if (ts.isJSDocTemplateTag(node.parent)) {
+                var container_1 = ts.find(node.parent.parent.tags, ts.isJSDocTypeAlias) || ts.getHostSignatureFromJSDoc(node.parent); // TODO: GH#18217
+                if (container_1) {
+                    if (!container_1.locals) {
+                        container_1.locals = ts.createSymbolTable();
+                    }
+                    declareSymbol(container_1.locals, /*parent*/ undefined, node, 262144 /* TypeParameter */, 67639784 /* TypeParameterExcludes */);
+                }
+                else {
+                    declareSymbolAndAddToSymbolTable(node, 262144 /* TypeParameter */, 67639784 /* TypeParameterExcludes */);
+                }
+            }
+            else if (node.parent.kind === 172 /* InferType */) {
+                var container_2 = getInferTypeContainer(node.parent);
+                if (container_2) {
+                    if (!container_2.locals) {
+                        container_2.locals = ts.createSymbolTable();
+                    }
+                    declareSymbol(container_2.locals, /*parent*/ undefined, node, 262144 /* TypeParameter */, 67639784 /* TypeParameterExcludes */);
+                }
+                else {
+                    bindAnonymousDeclaration(node, 262144 /* TypeParameter */, getDeclarationName(node)); // TODO: GH#18217
+                }
+            }
+            else {
+                declareSymbolAndAddToSymbolTable(node, 262144 /* TypeParameter */, 67639784 /* TypeParameterExcludes */);
+            }
+        }
+        // reachability checks
+        function shouldReportErrorOnModuleDeclaration(node) {
+            var instanceState = getModuleInstanceState(node);
+            return instanceState === 1 /* Instantiated */ || (instanceState === 2 /* ConstEnumOnly */ && !!options.preserveConstEnums);
+        }
+        function checkUnreachable(node) {
+            if (!(currentFlow.flags & 1 /* Unreachable */)) {
+                return false;
+            }
+            if (currentFlow === unreachableFlow) {
+                var reportError = 
+                // report error on all statements except empty ones
+                (ts.isStatementButNotDeclaration(node) && node.kind !== 215 /* EmptyStatement */) ||
+                    // report error on class declarations
+                    node.kind === 235 /* ClassDeclaration */ ||
+                    // report error on instantiated modules or const-enums only modules if preserveConstEnums is set
+                    (node.kind === 239 /* ModuleDeclaration */ && shouldReportErrorOnModuleDeclaration(node)) ||
+                    // report error on regular enums and const enums if preserveConstEnums is set
+                    (node.kind === 238 /* EnumDeclaration */ && (!ts.isConstEnumDeclaration(node) || options.preserveConstEnums));
+                if (reportError) {
+                    currentFlow = reportedUnreachableFlow;
+                    if (!options.allowUnreachableCode) {
+                        // unreachable code is reported if
+                        // - user has explicitly asked about it AND
+                        // - statement is in not ambient context (statements in ambient context is already an error
+                        //   so we should not report extras) AND
+                        //   - node is not variable statement OR
+                        //   - node is block scoped variable statement OR
+                        //   - node is not block scoped variable statement and at least one variable declaration has initializer
+                        //   Rationale: we don't want to report errors on non-initialized var's since they are hoisted
+                        //   On the other side we do want to report errors on non-initialized 'lets' because of TDZ
+                        var isError = ts.unreachableCodeIsError(options) &&
+                            !(node.flags & 4194304 /* Ambient */) &&
+                            (!ts.isVariableStatement(node) ||
+                                !!(ts.getCombinedNodeFlags(node.declarationList) & 3 /* BlockScoped */) ||
+                                node.declarationList.declarations.some(function (d) { return !!d.initializer; }));
+                        errorOrSuggestionOnFirstToken(isError, node, ts.Diagnostics.Unreachable_code_detected);
+                    }
+                }
+            }
+            return true;
+        }
+    }
+    /* @internal */
+    function isExportsOrModuleExportsOrAlias(sourceFile, node) {
+        return ts.isExportsIdentifier(node) ||
+            ts.isModuleExportsPropertyAccessExpression(node) ||
+            ts.isIdentifier(node) && isNameOfExportsOrModuleExportsAliasDeclaration(sourceFile, node);
+    }
+    ts.isExportsOrModuleExportsOrAlias = isExportsOrModuleExportsOrAlias;
+    function isNameOfExportsOrModuleExportsAliasDeclaration(sourceFile, node) {
+        var symbol = lookupSymbolForNameWorker(sourceFile, node.escapedText);
+        return !!symbol && !!symbol.valueDeclaration && ts.isVariableDeclaration(symbol.valueDeclaration) &&
+            !!symbol.valueDeclaration.initializer && isExportsOrModuleExportsOrAliasOrAssignment(sourceFile, symbol.valueDeclaration.initializer);
+    }
+    function isExportsOrModuleExportsOrAliasOrAssignment(sourceFile, node) {
+        return isExportsOrModuleExportsOrAlias(sourceFile, node) ||
+            (ts.isAssignmentExpression(node, /*excludeCompoundAssignment*/ true) && (isExportsOrModuleExportsOrAliasOrAssignment(sourceFile, node.left) || isExportsOrModuleExportsOrAliasOrAssignment(sourceFile, node.right)));
+    }
+    function lookupSymbolForNameWorker(container, name) {
+        var local = container.locals && container.locals.get(name);
+        if (local) {
+            return local.exportSymbol || local;
+        }
+        return container.symbol && container.symbol.exports && container.symbol.exports.get(name);
+    }
+    /**
+     * Computes the transform flags for a node, given the transform flags of its subtree
+     *
+     * @param node The node to analyze
+     * @param subtreeFlags Transform flags computed for this node's subtree
+     */
+    function computeTransformFlagsForNode(node, subtreeFlags) {
+        var kind = node.kind;
+        switch (kind) {
+            case 187 /* CallExpression */:
+                return computeCallExpression(node, subtreeFlags);
+            case 188 /* NewExpression */:
+                return computeNewExpression(node, subtreeFlags);
+            case 239 /* ModuleDeclaration */:
+                return computeModuleDeclaration(node, subtreeFlags);
+            case 191 /* ParenthesizedExpression */:
+                return computeParenthesizedExpression(node, subtreeFlags);
+            case 200 /* BinaryExpression */:
+                return computeBinaryExpression(node, subtreeFlags);
+            case 216 /* ExpressionStatement */:
+                return computeExpressionStatement(node, subtreeFlags);
+            case 149 /* Parameter */:
+                return computeParameter(node, subtreeFlags);
+            case 193 /* ArrowFunction */:
+                return computeArrowFunction(node, subtreeFlags);
+            case 192 /* FunctionExpression */:
+                return computeFunctionExpression(node, subtreeFlags);
+            case 234 /* FunctionDeclaration */:
+                return computeFunctionDeclaration(node, subtreeFlags);
+            case 232 /* VariableDeclaration */:
+                return computeVariableDeclaration(node, subtreeFlags);
+            case 233 /* VariableDeclarationList */:
+                return computeVariableDeclarationList(node, subtreeFlags);
+            case 214 /* VariableStatement */:
+                return computeVariableStatement(node, subtreeFlags);
+            case 228 /* LabeledStatement */:
+                return computeLabeledStatement(node, subtreeFlags);
+            case 235 /* ClassDeclaration */:
+                return computeClassDeclaration(node, subtreeFlags);
+            case 205 /* ClassExpression */:
+                return computeClassExpression(node, subtreeFlags);
+            case 268 /* HeritageClause */:
+                return computeHeritageClause(node, subtreeFlags);
+            case 269 /* CatchClause */:
+                return computeCatchClause(node, subtreeFlags);
+            case 207 /* ExpressionWithTypeArguments */:
+                return computeExpressionWithTypeArguments(node, subtreeFlags);
+            case 155 /* Constructor */:
+                return computeConstructor(node, subtreeFlags);
+            case 152 /* PropertyDeclaration */:
+                return computePropertyDeclaration(node, subtreeFlags);
+            case 154 /* MethodDeclaration */:
+                return computeMethod(node, subtreeFlags);
+            case 156 /* GetAccessor */:
+            case 157 /* SetAccessor */:
+                return computeAccessor(node, subtreeFlags);
+            case 243 /* ImportEqualsDeclaration */:
+                return computeImportEquals(node, subtreeFlags);
+            case 185 /* PropertyAccessExpression */:
+                return computePropertyAccess(node, subtreeFlags);
+            case 186 /* ElementAccessExpression */:
+                return computeElementAccess(node, subtreeFlags);
+            default:
+                return computeOther(node, kind, subtreeFlags);
+        }
+    }
+    ts.computeTransformFlagsForNode = computeTransformFlagsForNode;
+    function computeCallExpression(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        var expression = node.expression;
+        if (node.typeArguments) {
+            transformFlags |= 3 /* AssertTypeScript */;
+        }
+        if (subtreeFlags & 524288 /* ContainsSpread */
+            || (expression.transformFlags & (134217728 /* Super */ | 268435456 /* ContainsSuper */))) {
+            // If the this node contains a SpreadExpression, or is a super call, then it is an ES6
+            // node.
+            transformFlags |= 192 /* AssertES2015 */;
+            // super property or element accesses could be inside lambdas, etc, and need a captured `this`,
+            // while super keyword for super calls (indicated by TransformFlags.Super) does not (since it can only be top-level in a constructor)
+            if (expression.transformFlags & 268435456 /* ContainsSuper */) {
+                transformFlags |= 16384 /* ContainsLexicalThis */;
+            }
+        }
+        if (expression.kind === 91 /* ImportKeyword */) {
+            transformFlags |= 67108864 /* ContainsDynamicImport */;
+            // A dynamic 'import()' call that contains a lexical 'this' will
+            // require a captured 'this' when emitting down-level.
+            if (subtreeFlags & 16384 /* ContainsLexicalThis */) {
+                transformFlags |= 32768 /* ContainsCapturedLexicalThis */;
+            }
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~940049729 /* ArrayLiteralOrCallOrNewExcludes */;
+    }
+    function computeNewExpression(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        if (node.typeArguments) {
+            transformFlags |= 3 /* AssertTypeScript */;
+        }
+        if (subtreeFlags & 524288 /* ContainsSpread */) {
+            // If the this node contains a SpreadElementExpression then it is an ES6
+            // node.
+            transformFlags |= 192 /* AssertES2015 */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~940049729 /* ArrayLiteralOrCallOrNewExcludes */;
+    }
+    function computeBinaryExpression(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        var operatorTokenKind = node.operatorToken.kind;
+        var leftKind = node.left.kind;
+        if (operatorTokenKind === 58 /* EqualsToken */ && leftKind === 184 /* ObjectLiteralExpression */) {
+            // Destructuring object assignments with are ES2015 syntax
+            // and possibly ESNext if they contain rest
+            transformFlags |= 8 /* AssertESNext */ | 192 /* AssertES2015 */ | 3072 /* AssertDestructuringAssignment */;
+        }
+        else if (operatorTokenKind === 58 /* EqualsToken */ && leftKind === 183 /* ArrayLiteralExpression */) {
+            // Destructuring assignments are ES2015 syntax.
+            transformFlags |= 192 /* AssertES2015 */ | 3072 /* AssertDestructuringAssignment */;
+        }
+        else if (operatorTokenKind === 40 /* AsteriskAsteriskToken */
+            || operatorTokenKind === 62 /* AsteriskAsteriskEqualsToken */) {
+            // Exponentiation is ES2016 syntax.
+            transformFlags |= 32 /* AssertES2016 */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~939525441 /* NodeExcludes */;
+    }
+    function computeParameter(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        var name = node.name;
+        var initializer = node.initializer;
+        var dotDotDotToken = node.dotDotDotToken;
+        // The '?' token, type annotations, decorators, and 'this' parameters are TypeSCript
+        // syntax.
+        if (node.questionToken
+            || node.type
+            || subtreeFlags & 4096 /* ContainsDecorators */
+            || ts.isThisIdentifier(name)) {
+            transformFlags |= 3 /* AssertTypeScript */;
+        }
+        // If a parameter has an accessibility modifier, then it is TypeScript syntax.
+        if (ts.hasModifier(node, 92 /* ParameterPropertyModifier */)) {
+            transformFlags |= 3 /* AssertTypeScript */ | 262144 /* ContainsParameterPropertyAssignments */;
+        }
+        // parameters with object rest destructuring are ES Next syntax
+        if (subtreeFlags & 1048576 /* ContainsObjectRest */) {
+            transformFlags |= 8 /* AssertESNext */;
+        }
+        // If a parameter has an initializer, a binding pattern or a dotDotDot token, then
+        // it is ES6 syntax and its container must emit default value assignments or parameter destructuring downlevel.
+        if (subtreeFlags & 8388608 /* ContainsBindingPattern */ || initializer || dotDotDotToken) {
+            transformFlags |= 192 /* AssertES2015 */ | 131072 /* ContainsDefaultValueAssignments */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~939525441 /* ParameterExcludes */;
+    }
+    function computeParenthesizedExpression(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        var expression = node.expression;
+        var expressionKind = expression.kind;
+        var expressionTransformFlags = expression.transformFlags;
+        // If the node is synthesized, it means the emitter put the parentheses there,
+        // not the user. If we didn't want them, the emitter would not have put them
+        // there.
+        if (expressionKind === 208 /* AsExpression */
+            || expressionKind === 190 /* TypeAssertionExpression */) {
+            transformFlags |= 3 /* AssertTypeScript */;
+        }
+        // If the expression of a ParenthesizedExpression is a destructuring assignment,
+        // then the ParenthesizedExpression is a destructuring assignment.
+        if (expressionTransformFlags & 1024 /* DestructuringAssignment */) {
+            transformFlags |= 1024 /* DestructuringAssignment */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~536872257 /* OuterExpressionExcludes */;
+    }
+    function computeClassDeclaration(node, subtreeFlags) {
+        var transformFlags;
+        if (ts.hasModifier(node, 2 /* Ambient */)) {
+            // An ambient declaration is TypeScript syntax.
+            transformFlags = 3 /* AssertTypeScript */;
+        }
+        else {
+            // A ClassDeclaration is ES6 syntax.
+            transformFlags = subtreeFlags | 192 /* AssertES2015 */;
+            // A class with a parameter property assignment, property initializer, computed property name, or decorator is
+            // TypeScript syntax.
+            // An exported declaration may be TypeScript syntax, but is handled by the visitor
+            // for a namespace declaration.
+            if ((subtreeFlags & 274432 /* TypeScriptClassSyntaxMask */)
+                || node.typeParameters) {
+                transformFlags |= 3 /* AssertTypeScript */;
+            }
+            if (subtreeFlags & 65536 /* ContainsLexicalThisInComputedPropertyName */) {
+                // A computed property name containing `this` might need to be rewritten,
+                // so propagate the ContainsLexicalThis flag upward.
+                transformFlags |= 16384 /* ContainsLexicalThis */;
+            }
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~942011713 /* ClassExcludes */;
+    }
+    function computeClassExpression(node, subtreeFlags) {
+        // A ClassExpression is ES6 syntax.
+        var transformFlags = subtreeFlags | 192 /* AssertES2015 */;
+        // A class with a parameter property assignment, property initializer, or decorator is
+        // TypeScript syntax.
+        if (subtreeFlags & 274432 /* TypeScriptClassSyntaxMask */
+            || node.typeParameters) {
+            transformFlags |= 3 /* AssertTypeScript */;
+        }
+        if (subtreeFlags & 65536 /* ContainsLexicalThisInComputedPropertyName */) {
+            // A computed property name containing `this` might need to be rewritten,
+            // so propagate the ContainsLexicalThis flag upward.
+            transformFlags |= 16384 /* ContainsLexicalThis */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~942011713 /* ClassExcludes */;
+    }
+    function computeHeritageClause(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        switch (node.token) {
+            case 85 /* ExtendsKeyword */:
+                // An `extends` HeritageClause is ES6 syntax.
+                transformFlags |= 192 /* AssertES2015 */;
+                break;
+            case 108 /* ImplementsKeyword */:
+                // An `implements` HeritageClause is TypeScript syntax.
+                transformFlags |= 3 /* AssertTypeScript */;
+                break;
+            default:
+                ts.Debug.fail("Unexpected token for heritage clause");
+                break;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~939525441 /* NodeExcludes */;
+    }
+    function computeCatchClause(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        if (!node.variableDeclaration) {
+            transformFlags |= 8 /* AssertESNext */;
+        }
+        else if (ts.isBindingPattern(node.variableDeclaration.name)) {
+            transformFlags |= 192 /* AssertES2015 */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~940574017 /* CatchClauseExcludes */;
+    }
+    function computeExpressionWithTypeArguments(node, subtreeFlags) {
+        // An ExpressionWithTypeArguments is ES6 syntax, as it is used in the
+        // extends clause of a class.
+        var transformFlags = subtreeFlags | 192 /* AssertES2015 */;
+        // If an ExpressionWithTypeArguments contains type arguments, then it
+        // is TypeScript syntax.
+        if (node.typeArguments) {
+            transformFlags |= 3 /* AssertTypeScript */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~939525441 /* NodeExcludes */;
+    }
+    function computeConstructor(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        // TypeScript-specific modifiers and overloads are TypeScript syntax
+        if (ts.hasModifier(node, 2270 /* TypeScriptModifier */)
+            || !node.body) {
+            transformFlags |= 3 /* AssertTypeScript */;
+        }
+        // function declarations with object rest destructuring are ES Next syntax
+        if (subtreeFlags & 1048576 /* ContainsObjectRest */) {
+            transformFlags |= 8 /* AssertESNext */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~1003668801 /* ConstructorExcludes */;
+    }
+    function computeMethod(node, subtreeFlags) {
+        // A MethodDeclaration is ES6 syntax.
+        var transformFlags = subtreeFlags | 192 /* AssertES2015 */;
+        // Decorators, TypeScript-specific modifiers, type parameters, type annotations, and
+        // overloads are TypeScript syntax.
+        if (node.decorators
+            || ts.hasModifier(node, 2270 /* TypeScriptModifier */)
+            || node.typeParameters
+            || node.type
+            || (node.name && ts.isComputedPropertyName(node.name)) // While computed method names aren't typescript, the TS transform must visit them to emit property declarations correctly
+            || !node.body) {
+            transformFlags |= 3 /* AssertTypeScript */;
+        }
+        // function declarations with object rest destructuring are ES Next syntax
+        if (subtreeFlags & 1048576 /* ContainsObjectRest */) {
+            transformFlags |= 8 /* AssertESNext */;
+        }
+        // An async method declaration is ES2017 syntax.
+        if (ts.hasModifier(node, 256 /* Async */)) {
+            transformFlags |= node.asteriskToken ? 8 /* AssertESNext */ : 16 /* AssertES2017 */;
+        }
+        if (node.asteriskToken) {
+            transformFlags |= 768 /* AssertGenerator */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~1003668801 /* MethodOrAccessorExcludes */;
+    }
+    function computeAccessor(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        // Decorators, TypeScript-specific modifiers, type annotations, and overloads are
+        // TypeScript syntax.
+        if (node.decorators
+            || ts.hasModifier(node, 2270 /* TypeScriptModifier */)
+            || node.type
+            || (node.name && ts.isComputedPropertyName(node.name)) // While computed accessor names aren't typescript, the TS transform must visit them to emit property declarations correctly
+            || !node.body) {
+            transformFlags |= 3 /* AssertTypeScript */;
+        }
+        // function declarations with object rest destructuring are ES Next syntax
+        if (subtreeFlags & 1048576 /* ContainsObjectRest */) {
+            transformFlags |= 8 /* AssertESNext */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~1003668801 /* MethodOrAccessorExcludes */;
+    }
+    function computePropertyDeclaration(node, subtreeFlags) {
+        // A PropertyDeclaration is TypeScript syntax.
+        var transformFlags = subtreeFlags | 3 /* AssertTypeScript */;
+        // If the PropertyDeclaration has an initializer or a computed name, we need to inform its ancestor
+        // so that it handle the transformation.
+        if (node.initializer || ts.isComputedPropertyName(node.name)) {
+            transformFlags |= 8192 /* ContainsPropertyInitializer */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~939525441 /* NodeExcludes */;
+    }
+    function computeFunctionDeclaration(node, subtreeFlags) {
+        var transformFlags;
+        var modifierFlags = ts.getModifierFlags(node);
+        var body = node.body;
+        if (!body || (modifierFlags & 2 /* Ambient */)) {
+            // An ambient declaration is TypeScript syntax.
+            // A FunctionDeclaration without a body is an overload and is TypeScript syntax.
+            transformFlags = 3 /* AssertTypeScript */;
+        }
+        else {
+            transformFlags = subtreeFlags | 33554432 /* ContainsHoistedDeclarationOrCompletion */;
+            // TypeScript-specific modifiers, type parameters, and type annotations are TypeScript
+            // syntax.
+            if (modifierFlags & 2270 /* TypeScriptModifier */
+                || node.typeParameters
+                || node.type) {
+                transformFlags |= 3 /* AssertTypeScript */;
+            }
+            // An async function declaration is ES2017 syntax.
+            if (modifierFlags & 256 /* Async */) {
+                transformFlags |= node.asteriskToken ? 8 /* AssertESNext */ : 16 /* AssertES2017 */;
+            }
+            // function declarations with object rest destructuring are ES Next syntax
+            if (subtreeFlags & 1048576 /* ContainsObjectRest */) {
+                transformFlags |= 8 /* AssertESNext */;
+            }
+            // If a FunctionDeclaration's subtree has marked the container as needing to capture the
+            // lexical this, or the function contains parameters with initializers, then this node is
+            // ES6 syntax.
+            if (subtreeFlags & 163840 /* ES2015FunctionSyntaxMask */) {
+                transformFlags |= 192 /* AssertES2015 */;
+            }
+            // If a FunctionDeclaration is generator function and is the body of a
+            // transformed async function, then this node can be transformed to a
+            // down-level generator.
+            // Currently we do not support transforming any other generator fucntions
+            // down level.
+            if (node.asteriskToken) {
+                transformFlags |= 768 /* AssertGenerator */;
+            }
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~1003935041 /* FunctionExcludes */;
+    }
+    function computeFunctionExpression(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        // TypeScript-specific modifiers, type parameters, and type annotations are TypeScript
+        // syntax.
+        if (ts.hasModifier(node, 2270 /* TypeScriptModifier */)
+            || node.typeParameters
+            || node.type) {
+            transformFlags |= 3 /* AssertTypeScript */;
+        }
+        // An async function expression is ES2017 syntax.
+        if (ts.hasModifier(node, 256 /* Async */)) {
+            transformFlags |= node.asteriskToken ? 8 /* AssertESNext */ : 16 /* AssertES2017 */;
+        }
+        // function expressions with object rest destructuring are ES Next syntax
+        if (subtreeFlags & 1048576 /* ContainsObjectRest */) {
+            transformFlags |= 8 /* AssertESNext */;
+        }
+        // If a FunctionExpression's subtree has marked the container as needing to capture the
+        // lexical this, or the function contains parameters with initializers, then this node is
+        // ES6 syntax.
+        if (subtreeFlags & 163840 /* ES2015FunctionSyntaxMask */) {
+            transformFlags |= 192 /* AssertES2015 */;
+        }
+        // If a FunctionExpression is generator function and is the body of a
+        // transformed async function, then this node can be transformed to a
+        // down-level generator.
+        if (node.asteriskToken) {
+            transformFlags |= 768 /* AssertGenerator */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~1003935041 /* FunctionExcludes */;
+    }
+    function computeArrowFunction(node, subtreeFlags) {
+        // An ArrowFunction is ES6 syntax, and excludes markers that should not escape the scope of an ArrowFunction.
+        var transformFlags = subtreeFlags | 192 /* AssertES2015 */;
+        // TypeScript-specific modifiers, type parameters, and type annotations are TypeScript
+        // syntax.
+        if (ts.hasModifier(node, 2270 /* TypeScriptModifier */)
+            || node.typeParameters
+            || node.type) {
+            transformFlags |= 3 /* AssertTypeScript */;
+        }
+        // An async arrow function is ES2017 syntax.
+        if (ts.hasModifier(node, 256 /* Async */)) {
+            transformFlags |= 16 /* AssertES2017 */;
+        }
+        // arrow functions with object rest destructuring are ES Next syntax
+        if (subtreeFlags & 1048576 /* ContainsObjectRest */) {
+            transformFlags |= 8 /* AssertESNext */;
+        }
+        // If an ArrowFunction contains a lexical this, its container must capture the lexical this.
+        if (subtreeFlags & 16384 /* ContainsLexicalThis */) {
+            transformFlags |= 32768 /* ContainsCapturedLexicalThis */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~1003902273 /* ArrowFunctionExcludes */;
+    }
+    function computePropertyAccess(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        // If a PropertyAccessExpression starts with a super keyword, then it is
+        // ES6 syntax, and requires a lexical `this` binding.
+        if (transformFlags & 134217728 /* Super */) {
+            transformFlags ^= 134217728 /* Super */;
+            transformFlags |= 268435456 /* ContainsSuper */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~671089985 /* PropertyAccessExcludes */;
+    }
+    function computeElementAccess(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        var expression = node.expression;
+        var expressionFlags = expression.transformFlags; // We do not want to aggregate flags from the argument expression for super/this capturing
+        // If an ElementAccessExpression starts with a super keyword, then it is
+        // ES6 syntax, and requires a lexical `this` binding.
+        if (expressionFlags & 134217728 /* Super */) {
+            transformFlags &= ~134217728 /* Super */;
+            transformFlags |= 268435456 /* ContainsSuper */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~671089985 /* PropertyAccessExcludes */;
+    }
+    function computeVariableDeclaration(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        transformFlags |= 192 /* AssertES2015 */ | 8388608 /* ContainsBindingPattern */;
+        // A VariableDeclaration containing ObjectRest is ESNext syntax
+        if (subtreeFlags & 1048576 /* ContainsObjectRest */) {
+            transformFlags |= 8 /* AssertESNext */;
+        }
+        // Type annotations are TypeScript syntax.
+        if (node.type) {
+            transformFlags |= 3 /* AssertTypeScript */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~939525441 /* NodeExcludes */;
+    }
+    function computeVariableStatement(node, subtreeFlags) {
+        var transformFlags;
+        var declarationListTransformFlags = node.declarationList.transformFlags;
+        // An ambient declaration is TypeScript syntax.
+        if (ts.hasModifier(node, 2 /* Ambient */)) {
+            transformFlags = 3 /* AssertTypeScript */;
+        }
+        else {
+            transformFlags = subtreeFlags;
+            if (declarationListTransformFlags & 8388608 /* ContainsBindingPattern */) {
+                transformFlags |= 192 /* AssertES2015 */;
+            }
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~939525441 /* NodeExcludes */;
+    }
+    function computeLabeledStatement(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        // A labeled statement containing a block scoped binding *may* need to be transformed from ES6.
+        if (subtreeFlags & 4194304 /* ContainsBlockScopedBinding */
+            && ts.isIterationStatement(node, /*lookInLabeledStatements*/ true)) {
+            transformFlags |= 192 /* AssertES2015 */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~939525441 /* NodeExcludes */;
+    }
+    function computeImportEquals(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        // An ImportEqualsDeclaration with a namespace reference is TypeScript.
+        if (!ts.isExternalModuleImportEqualsDeclaration(node)) {
+            transformFlags |= 3 /* AssertTypeScript */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~939525441 /* NodeExcludes */;
+    }
+    function computeExpressionStatement(node, subtreeFlags) {
+        var transformFlags = subtreeFlags;
+        // If the expression of an expression statement is a destructuring assignment,
+        // then we treat the statement as ES6 so that we can indicate that we do not
+        // need to hold on to the right-hand side.
+        if (node.expression.transformFlags & 1024 /* DestructuringAssignment */) {
+            transformFlags |= 192 /* AssertES2015 */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~939525441 /* NodeExcludes */;
+    }
+    function computeModuleDeclaration(node, subtreeFlags) {
+        var transformFlags = 3 /* AssertTypeScript */;
+        var modifierFlags = ts.getModifierFlags(node);
+        if ((modifierFlags & 2 /* Ambient */) === 0) {
+            transformFlags |= subtreeFlags;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~977327425 /* ModuleExcludes */;
+    }
+    function computeVariableDeclarationList(node, subtreeFlags) {
+        var transformFlags = subtreeFlags | 33554432 /* ContainsHoistedDeclarationOrCompletion */;
+        if (subtreeFlags & 8388608 /* ContainsBindingPattern */) {
+            transformFlags |= 192 /* AssertES2015 */;
+        }
+        // If a VariableDeclarationList is `let` or `const`, then it is ES6 syntax.
+        if (node.flags & 3 /* BlockScoped */) {
+            transformFlags |= 192 /* AssertES2015 */ | 4194304 /* ContainsBlockScopedBinding */;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~948962625 /* VariableDeclarationListExcludes */;
+    }
+    function computeOther(node, kind, subtreeFlags) {
+        // Mark transformations needed for each node
+        var transformFlags = subtreeFlags;
+        var excludeFlags = 939525441 /* NodeExcludes */;
+        switch (kind) {
+            case 120 /* AsyncKeyword */:
+            case 197 /* AwaitExpression */:
+                // async/await is ES2017 syntax, but may be ESNext syntax (for async generators)
+                transformFlags |= 8 /* AssertESNext */ | 16 /* AssertES2017 */;
+                break;
+            case 190 /* TypeAssertionExpression */:
+            case 208 /* AsExpression */:
+            case 301 /* PartiallyEmittedExpression */:
+                // These nodes are TypeScript syntax.
+                transformFlags |= 3 /* AssertTypeScript */;
+                excludeFlags = 536872257 /* OuterExpressionExcludes */;
+                break;
+            case 114 /* PublicKeyword */:
+            case 112 /* PrivateKeyword */:
+            case 113 /* ProtectedKeyword */:
+            case 117 /* AbstractKeyword */:
+            case 124 /* DeclareKeyword */:
+            case 76 /* ConstKeyword */:
+            case 238 /* EnumDeclaration */:
+            case 273 /* EnumMember */:
+            case 209 /* NonNullExpression */:
+            case 132 /* ReadonlyKeyword */:
+                // These nodes are TypeScript syntax.
+                transformFlags |= 3 /* AssertTypeScript */;
+                break;
+            case 255 /* JsxElement */:
+            case 256 /* JsxSelfClosingElement */:
+            case 257 /* JsxOpeningElement */:
+            case 10 /* JsxText */:
+            case 258 /* JsxClosingElement */:
+            case 259 /* JsxFragment */:
+            case 260 /* JsxOpeningFragment */:
+            case 261 /* JsxClosingFragment */:
+            case 262 /* JsxAttribute */:
+            case 263 /* JsxAttributes */:
+            case 264 /* JsxSpreadAttribute */:
+            case 265 /* JsxExpression */:
+                // These nodes are Jsx syntax.
+                transformFlags |= 4 /* AssertJsx */;
+                break;
+            case 13 /* NoSubstitutionTemplateLiteral */:
+            case 14 /* TemplateHead */:
+            case 15 /* TemplateMiddle */:
+            case 16 /* TemplateTail */:
+            case 202 /* TemplateExpression */:
+            case 189 /* TaggedTemplateExpression */:
+            case 271 /* ShorthandPropertyAssignment */:
+            case 115 /* StaticKeyword */:
+            case 210 /* MetaProperty */:
+                // These nodes are ES6 syntax.
+                transformFlags |= 192 /* AssertES2015 */;
+                break;
+            case 9 /* StringLiteral */:
+                if (node.hasExtendedUnicodeEscape) {
+                    transformFlags |= 192 /* AssertES2015 */;
+                }
+                break;
+            case 8 /* NumericLiteral */:
+                if (node.numericLiteralFlags & 384 /* BinaryOrOctalSpecifier */) {
+                    transformFlags |= 192 /* AssertES2015 */;
+                }
+                break;
+            case 222 /* ForOfStatement */:
+                // This node is either ES2015 syntax or ES2017 syntax (if it is a for-await-of).
+                if (node.awaitModifier) {
+                    transformFlags |= 8 /* AssertESNext */;
+                }
+                transformFlags |= 192 /* AssertES2015 */;
+                break;
+            case 203 /* YieldExpression */:
+                // This node is either ES2015 syntax (in a generator) or ES2017 syntax (in an async
+                // generator).
+                transformFlags |= 8 /* AssertESNext */ | 192 /* AssertES2015 */ | 16777216 /* ContainsYield */;
+                break;
+            case 119 /* AnyKeyword */:
+            case 134 /* NumberKeyword */:
+            case 131 /* NeverKeyword */:
+            case 135 /* ObjectKeyword */:
+            case 137 /* StringKeyword */:
+            case 122 /* BooleanKeyword */:
+            case 138 /* SymbolKeyword */:
+            case 105 /* VoidKeyword */:
+            case 148 /* TypeParameter */:
+            case 151 /* PropertySignature */:
+            case 153 /* MethodSignature */:
+            case 158 /* CallSignature */:
+            case 159 /* ConstructSignature */:
+            case 160 /* IndexSignature */:
+            case 161 /* TypePredicate */:
+            case 162 /* TypeReference */:
+            case 163 /* FunctionType */:
+            case 164 /* ConstructorType */:
+            case 165 /* TypeQuery */:
+            case 166 /* TypeLiteral */:
+            case 167 /* ArrayType */:
+            case 168 /* TupleType */:
+            case 169 /* UnionType */:
+            case 170 /* IntersectionType */:
+            case 171 /* ConditionalType */:
+            case 172 /* InferType */:
+            case 173 /* ParenthesizedType */:
+            case 236 /* InterfaceDeclaration */:
+            case 237 /* TypeAliasDeclaration */:
+            case 174 /* ThisType */:
+            case 175 /* TypeOperator */:
+            case 176 /* IndexedAccessType */:
+            case 177 /* MappedType */:
+            case 178 /* LiteralType */:
+            case 242 /* NamespaceExportDeclaration */:
+                // Types and signatures are TypeScript syntax, and exclude all other facts.
+                transformFlags = 3 /* AssertTypeScript */;
+                excludeFlags = -3 /* TypeExcludes */;
+                break;
+            case 147 /* ComputedPropertyName */:
+                // Even though computed property names are ES6, we don't treat them as such.
+                // This is so that they can flow through PropertyName transforms unaffected.
+                // Instead, we mark the container as ES6, so that it can properly handle the transform.
+                transformFlags |= 2097152 /* ContainsComputedPropertyName */;
+                if (subtreeFlags & 16384 /* ContainsLexicalThis */) {
+                    // A computed method name like `[this.getName()](x: string) { ... }` needs to
+                    // distinguish itself from the normal case of a method body containing `this`:
+                    // `this` inside a method doesn't need to be rewritten (the method provides `this`),
+                    // whereas `this` inside a computed name *might* need to be rewritten if the class/object
+                    // is inside an arrow function:
+                    // `_this = this; () => class K { [_this.getName()]() { ... } }`
+                    // To make this distinction, use ContainsLexicalThisInComputedPropertyName
+                    // instead of ContainsLexicalThis for computed property names
+                    transformFlags |= 65536 /* ContainsLexicalThisInComputedPropertyName */;
+                }
+                break;
+            case 204 /* SpreadElement */:
+                transformFlags |= 192 /* AssertES2015 */ | 524288 /* ContainsSpread */;
+                break;
+            case 272 /* SpreadAssignment */:
+                transformFlags |= 8 /* AssertESNext */ | 1048576 /* ContainsObjectSpread */;
+                break;
+            case 97 /* SuperKeyword */:
+                // This node is ES6 syntax.
+                transformFlags |= 192 /* AssertES2015 */ | 134217728 /* Super */;
+                excludeFlags = 536872257 /* OuterExpressionExcludes */; // must be set to persist `Super`
+                break;
+            case 99 /* ThisKeyword */:
+                // Mark this node and its ancestors as containing a lexical `this` keyword.
+                transformFlags |= 16384 /* ContainsLexicalThis */;
+                break;
+            case 180 /* ObjectBindingPattern */:
+                transformFlags |= 192 /* AssertES2015 */ | 8388608 /* ContainsBindingPattern */;
+                if (subtreeFlags & 524288 /* ContainsRest */) {
+                    transformFlags |= 8 /* AssertESNext */ | 1048576 /* ContainsObjectRest */;
+                }
+                excludeFlags = 940049729 /* BindingPatternExcludes */;
+                break;
+            case 181 /* ArrayBindingPattern */:
+                transformFlags |= 192 /* AssertES2015 */ | 8388608 /* ContainsBindingPattern */;
+                excludeFlags = 940049729 /* BindingPatternExcludes */;
+                break;
+            case 182 /* BindingElement */:
+                transformFlags |= 192 /* AssertES2015 */;
+                if (node.dotDotDotToken) {
+                    transformFlags |= 524288 /* ContainsRest */;
+                }
+                break;
+            case 150 /* Decorator */:
+                // This node is TypeScript syntax, and marks its container as also being TypeScript syntax.
+                transformFlags |= 3 /* AssertTypeScript */ | 4096 /* ContainsDecorators */;
+                break;
+            case 184 /* ObjectLiteralExpression */:
+                excludeFlags = 942740801 /* ObjectLiteralExcludes */;
+                if (subtreeFlags & 2097152 /* ContainsComputedPropertyName */) {
+                    // If an ObjectLiteralExpression contains a ComputedPropertyName, then it
+                    // is an ES6 node.
+                    transformFlags |= 192 /* AssertES2015 */;
+                }
+                if (subtreeFlags & 65536 /* ContainsLexicalThisInComputedPropertyName */) {
+                    // A computed property name containing `this` might need to be rewritten,
+                    // so propagate the ContainsLexicalThis flag upward.
+                    transformFlags |= 16384 /* ContainsLexicalThis */;
+                }
+                if (subtreeFlags & 1048576 /* ContainsObjectSpread */) {
+                    // If an ObjectLiteralExpression contains a spread element, then it
+                    // is an ES next node.
+                    transformFlags |= 8 /* AssertESNext */;
+                }
+                break;
+            case 183 /* ArrayLiteralExpression */:
+            case 188 /* NewExpression */:
+                excludeFlags = 940049729 /* ArrayLiteralOrCallOrNewExcludes */;
+                if (subtreeFlags & 524288 /* ContainsSpread */) {
+                    // If the this node contains a SpreadExpression, then it is an ES6
+                    // node.
+                    transformFlags |= 192 /* AssertES2015 */;
+                }
+                break;
+            case 218 /* DoStatement */:
+            case 219 /* WhileStatement */:
+            case 220 /* ForStatement */:
+            case 221 /* ForInStatement */:
+                // A loop containing a block scoped binding *may* need to be transformed from ES6.
+                if (subtreeFlags & 4194304 /* ContainsBlockScopedBinding */) {
+                    transformFlags |= 192 /* AssertES2015 */;
+                }
+                break;
+            case 274 /* SourceFile */:
+                if (subtreeFlags & 32768 /* ContainsCapturedLexicalThis */) {
+                    transformFlags |= 192 /* AssertES2015 */;
+                }
+                break;
+            case 225 /* ReturnStatement */:
+                // Return statements may require an `await` in ESNext.
+                transformFlags |= 33554432 /* ContainsHoistedDeclarationOrCompletion */ | 8 /* AssertESNext */;
+                break;
+            case 223 /* ContinueStatement */:
+            case 224 /* BreakStatement */:
+                transformFlags |= 33554432 /* ContainsHoistedDeclarationOrCompletion */;
+                break;
+        }
+        node.transformFlags = transformFlags | 536870912 /* HasComputedFlags */;
+        return transformFlags & ~excludeFlags;
+    }
+    /**
+     * Gets the transform flags to exclude when unioning the transform flags of a subtree.
+     *
+     * NOTE: This needs to be kept up-to-date with the exclusions used in `computeTransformFlagsForNode`.
+     *       For performance reasons, `computeTransformFlagsForNode` uses local constant values rather
+     *       than calling this function.
+     */
+    /* @internal */
+    function getTransformFlagsSubtreeExclusions(kind) {
+        if (kind >= 161 /* FirstTypeNode */ && kind <= 179 /* LastTypeNode */) {
+            return -3 /* TypeExcludes */;
+        }
+        switch (kind) {
+            case 187 /* CallExpression */:
+            case 188 /* NewExpression */:
+            case 183 /* ArrayLiteralExpression */:
+                return 940049729 /* ArrayLiteralOrCallOrNewExcludes */;
+            case 239 /* ModuleDeclaration */:
+                return 977327425 /* ModuleExcludes */;
+            case 149 /* Parameter */:
+                return 939525441 /* ParameterExcludes */;
+            case 193 /* ArrowFunction */:
+                return 1003902273 /* ArrowFunctionExcludes */;
+            case 192 /* FunctionExpression */:
+            case 234 /* FunctionDeclaration */:
+                return 1003935041 /* FunctionExcludes */;
+            case 233 /* VariableDeclarationList */:
+                return 948962625 /* VariableDeclarationListExcludes */;
+            case 235 /* ClassDeclaration */:
+            case 205 /* ClassExpression */:
+                return 942011713 /* ClassExcludes */;
+            case 155 /* Constructor */:
+                return 1003668801 /* ConstructorExcludes */;
+            case 154 /* MethodDeclaration */:
+            case 156 /* GetAccessor */:
+            case 157 /* SetAccessor */:
+                return 1003668801 /* MethodOrAccessorExcludes */;
+            case 119 /* AnyKeyword */:
+            case 134 /* NumberKeyword */:
+            case 131 /* NeverKeyword */:
+            case 137 /* StringKeyword */:
+            case 135 /* ObjectKeyword */:
+            case 122 /* BooleanKeyword */:
+            case 138 /* SymbolKeyword */:
+            case 105 /* VoidKeyword */:
+            case 148 /* TypeParameter */:
+            case 151 /* PropertySignature */:
+            case 153 /* MethodSignature */:
+            case 158 /* CallSignature */:
+            case 159 /* ConstructSignature */:
+            case 160 /* IndexSignature */:
+            case 236 /* InterfaceDeclaration */:
+            case 237 /* TypeAliasDeclaration */:
+                return -3 /* TypeExcludes */;
+            case 184 /* ObjectLiteralExpression */:
+                return 942740801 /* ObjectLiteralExcludes */;
+            case 269 /* CatchClause */:
+                return 940574017 /* CatchClauseExcludes */;
+            case 180 /* ObjectBindingPattern */:
+            case 181 /* ArrayBindingPattern */:
+                return 940049729 /* BindingPatternExcludes */;
+            case 190 /* TypeAssertionExpression */:
+            case 208 /* AsExpression */:
+            case 301 /* PartiallyEmittedExpression */:
+            case 191 /* ParenthesizedExpression */:
+            case 97 /* SuperKeyword */:
+                return 536872257 /* OuterExpressionExcludes */;
+            case 185 /* PropertyAccessExpression */:
+            case 186 /* ElementAccessExpression */:
+                return 671089985 /* PropertyAccessExcludes */;
+            default:
+                return 939525441 /* NodeExcludes */;
+        }
+    }
+    ts.getTransformFlagsSubtreeExclusions = getTransformFlagsSubtreeExclusions;
+    /**
+     * "Binds" JSDoc nodes in TypeScript code.
+     * Since we will never create symbols for JSDoc, we just set parent pointers instead.
+     */
+    function setParentPointers(parent, child) {
+        child.parent = parent;
+        ts.forEachChild(child, function (grandchild) { return setParentPointers(child, grandchild); });
+    }
+})(ts || (ts = {}));
+/** @internal */
+var ts;
+(function (ts) {
+    function createGetSymbolWalker(getRestTypeOfSignature, getTypePredicateOfSignature, getReturnTypeOfSignature, getBaseTypes, resolveStructuredTypeMembers, getTypeOfSymbol, getResolvedSymbol, getIndexTypeOfStructuredType, getConstraintFromTypeParameter, getFirstIdentifier) {
+        return getSymbolWalker;
+        function getSymbolWalker(accept) {
+            if (accept === void 0) { accept = function () { return true; }; }
+            var visitedTypes = []; // Sparse array from id to type
+            var visitedSymbols = []; // Sparse array from id to symbol
+            return {
+                walkType: function (type) {
+                    try {
+                        visitType(type);
+                        return { visitedTypes: ts.getOwnValues(visitedTypes), visitedSymbols: ts.getOwnValues(visitedSymbols) };
+                    }
+                    finally {
+                        ts.clear(visitedTypes);
+                        ts.clear(visitedSymbols);
+                    }
+                },
+                walkSymbol: function (symbol) {
+                    try {
+                        visitSymbol(symbol);
+                        return { visitedTypes: ts.getOwnValues(visitedTypes), visitedSymbols: ts.getOwnValues(visitedSymbols) };
+                    }
+                    finally {
+                        ts.clear(visitedTypes);
+                        ts.clear(visitedSymbols);
+                    }
+                },
+            };
+            function visitType(type) {
+                if (!type) {
+                    return;
+                }
+                if (visitedTypes[type.id]) {
+                    return;
+                }
+                visitedTypes[type.id] = type;
+                // Reuse visitSymbol to visit the type's symbol,
+                //  but be sure to bail on recuring into the type if accept declines the symbol.
+                var shouldBail = visitSymbol(type.symbol);
+                if (shouldBail)
+                    return;
+                // Visit the type's related types, if any
+                if (type.flags & 131072 /* Object */) {
+                    var objectType = type;
+                    var objectFlags = objectType.objectFlags;
+                    if (objectFlags & 4 /* Reference */) {
+                        visitTypeReference(type);
+                    }
+                    if (objectFlags & 32 /* Mapped */) {
+                        visitMappedType(type);
+                    }
+                    if (objectFlags & (1 /* Class */ | 2 /* Interface */)) {
+                        visitInterfaceType(type);
+                    }
+                    if (objectFlags & (8 /* Tuple */ | 16 /* Anonymous */)) {
+                        visitObjectType(objectType);
+                    }
+                }
+                if (type.flags & 65536 /* TypeParameter */) {
+                    visitTypeParameter(type);
+                }
+                if (type.flags & 786432 /* UnionOrIntersection */) {
+                    visitUnionOrIntersectionType(type);
+                }
+                if (type.flags & 1048576 /* Index */) {
+                    visitIndexType(type);
+                }
+                if (type.flags & 2097152 /* IndexedAccess */) {
+                    visitIndexedAccessType(type);
+                }
+            }
+            function visitTypeReference(type) {
+                visitType(type.target);
+                ts.forEach(type.typeArguments, visitType);
+            }
+            function visitTypeParameter(type) {
+                visitType(getConstraintFromTypeParameter(type));
+            }
+            function visitUnionOrIntersectionType(type) {
+                ts.forEach(type.types, visitType);
+            }
+            function visitIndexType(type) {
+                visitType(type.type);
+            }
+            function visitIndexedAccessType(type) {
+                visitType(type.objectType);
+                visitType(type.indexType);
+                visitType(type.constraint);
+            }
+            function visitMappedType(type) {
+                visitType(type.typeParameter);
+                visitType(type.constraintType);
+                visitType(type.templateType);
+                visitType(type.modifiersType);
+            }
+            function visitSignature(signature) {
+                var typePredicate = getTypePredicateOfSignature(signature);
+                if (typePredicate) {
+                    visitType(typePredicate.type);
+                }
+                ts.forEach(signature.typeParameters, visitType);
+                for (var _i = 0, _a = signature.parameters; _i < _a.length; _i++) {
+                    var parameter = _a[_i];
+                    visitSymbol(parameter);
+                }
+                visitType(getRestTypeOfSignature(signature));
+                visitType(getReturnTypeOfSignature(signature));
+            }
+            function visitInterfaceType(interfaceT) {
+                visitObjectType(interfaceT);
+                ts.forEach(interfaceT.typeParameters, visitType);
+                ts.forEach(getBaseTypes(interfaceT), visitType);
+                visitType(interfaceT.thisType);
+            }
+            function visitObjectType(type) {
+                var stringIndexType = getIndexTypeOfStructuredType(type, 0 /* String */);
+                visitType(stringIndexType);
+                var numberIndexType = getIndexTypeOfStructuredType(type, 1 /* Number */);
+                visitType(numberIndexType);
+                // The two checks above *should* have already resolved the type (if needed), so this should be cached
+                var resolved = resolveStructuredTypeMembers(type);
+                for (var _i = 0, _a = resolved.callSignatures; _i < _a.length; _i++) {
+                    var signature = _a[_i];
+                    visitSignature(signature);
+                }
+                for (var _b = 0, _c = resolved.constructSignatures; _b < _c.length; _b++) {
+                    var signature = _c[_b];
+                    visitSignature(signature);
+                }
+                for (var _d = 0, _e = resolved.properties; _d < _e.length; _d++) {
+                    var p = _e[_d];
+                    visitSymbol(p);
+                }
+            }
+            function visitSymbol(symbol) {
+                if (!symbol) {
+                    return false;
+                }
+                var symbolId = ts.getSymbolId(symbol);
+                if (visitedSymbols[symbolId]) {
+                    return false;
+                }
+                visitedSymbols[symbolId] = symbol;
+                if (!accept(symbol)) {
+                    return true;
+                }
+                var t = getTypeOfSymbol(symbol);
+                visitType(t); // Should handle members on classes and such
+                if (symbol.flags & 1955 /* HasExports */) {
+                    symbol.exports.forEach(visitSymbol);
+                }
+                ts.forEach(symbol.declarations, function (d) {
+                    // Type queries are too far resolved when we just visit the symbol's type
+                    //  (their type resolved directly to the member deeply referenced)
+                    // So to get the intervening symbols, we need to check if there's a type
+                    // query node on any of the symbol's declarations and get symbols there
+                    if (d.type && d.type.kind === 165 /* TypeQuery */) {
+                        var query = d.type;
+                        var entity = getResolvedSymbol(getFirstIdentifier(query.exprName));
+                        visitSymbol(entity);
+                    }
+                });
+                return false;
+            }
+        }
+    }
+    ts.createGetSymbolWalker = createGetSymbolWalker;
+})(ts || (ts = {}));
+/* @internal */
+var ts;
+(function (ts) {
+    var ambientModuleSymbolRegex = /^".+"$/;
+    var nextSymbolId = 1;
+    var nextNodeId = 1;
+    var nextMergeId = 1;
+    var nextFlowId = 1;
+    function getNodeId(node) {
+        if (!node.id) {
+            node.id = nextNodeId;
+            nextNodeId++;
+        }
+        return node.id;
+    }
+    ts.getNodeId = getNodeId;
+    function getSymbolId(symbol) {
+        if (!symbol.id) {
+            symbol.id = nextSymbolId;
+            nextSymbolId++;
+        }
+        return symbol.id;
+    }
+    ts.getSymbolId = getSymbolId;
+    function isInstantiatedModule(node, preserveConstEnums) {
+        var moduleState = ts.getModuleInstanceState(node);
+        return moduleState === 1 /* Instantiated */ ||
+            (preserveConstEnums && moduleState === 2 /* ConstEnumOnly */);
+    }
+    ts.isInstantiatedModule = isInstantiatedModule;
+    function createTypeChecker(host, produceDiagnostics) {
+        // Cancellation that controls whether or not we can cancel in the middle of type checking.
+        // In general cancelling is *not* safe for the type checker.  We might be in the middle of
+        // computing something, and we will leave our internals in an inconsistent state.  Callers
+        // who set the cancellation token should catch if a cancellation exception occurs, and
+        // should throw away and create a new TypeChecker.
+        //
+        // Currently we only support setting the cancellation token when getting diagnostics.  This
+        // is because diagnostics can be quite expensive, and we want to allow hosts to bail out if
+        // they no longer need the information (for example, if the user started editing again).
+        var cancellationToken;
+        var requestedExternalEmitHelpers;
+        var externalHelpersModule;
+        // tslint:disable variable-name
+        var Symbol = ts.objectAllocator.getSymbolConstructor();
+        var Type = ts.objectAllocator.getTypeConstructor();
+        var Signature = ts.objectAllocator.getSignatureConstructor();
+        // tslint:enable variable-name
+        var typeCount = 0;
+        var symbolCount = 0;
+        var enumCount = 0;
+        var symbolInstantiationDepth = 0;
+        var emptySymbols = ts.createSymbolTable();
+        var identityMapper = ts.identity;
+        var compilerOptions = host.getCompilerOptions();
+        var languageVersion = ts.getEmitScriptTarget(compilerOptions);
+        var moduleKind = ts.getEmitModuleKind(compilerOptions);
+        var allowSyntheticDefaultImports = ts.getAllowSyntheticDefaultImports(compilerOptions);
+        var strictNullChecks = ts.getStrictOptionValue(compilerOptions, "strictNullChecks");
+        var strictFunctionTypes = ts.getStrictOptionValue(compilerOptions, "strictFunctionTypes");
+        var strictPropertyInitialization = ts.getStrictOptionValue(compilerOptions, "strictPropertyInitialization");
+        var noImplicitAny = ts.getStrictOptionValue(compilerOptions, "noImplicitAny");
+        var noImplicitThis = ts.getStrictOptionValue(compilerOptions, "noImplicitThis");
+        var keyofStringsOnly = !!compilerOptions.keyofStringsOnly;
+        var emitResolver = createResolver();
+        var nodeBuilder = createNodeBuilder();
+        var undefinedSymbol = createSymbol(4 /* Property */, "undefined");
+        undefinedSymbol.declarations = [];
+        var argumentsSymbol = createSymbol(4 /* Property */, "arguments");
+        var requireSymbol = createSymbol(4 /* Property */, "require");
+        var moduleSymbol = createSymbol(4 /* Property */, "module");
+        /** This will be set during calls to `getResolvedSignature` where services determines an apparent number of arguments greater than what is actually provided. */
+        var apparentArgumentCount;
+        // for public members that accept a Node or one of its subtypes, we must guard against
+        // synthetic nodes created during transformations by calling `getParseTreeNode`.
+        // for most of these, we perform the guard only on `checker` to avoid any possible
+        // extra cost of calling `getParseTreeNode` when calling these functions from inside the
+        // checker.
+        var checker = {
+            getNodeCount: function () { return ts.sum(host.getSourceFiles(), "nodeCount"); },
+            getIdentifierCount: function () { return ts.sum(host.getSourceFiles(), "identifierCount"); },
+            getSymbolCount: function () { return ts.sum(host.getSourceFiles(), "symbolCount") + symbolCount; },
+            getTypeCount: function () { return typeCount; },
+            isUndefinedSymbol: function (symbol) { return symbol === undefinedSymbol; },
+            isArgumentsSymbol: function (symbol) { return symbol === argumentsSymbol; },
+            isUnknownSymbol: function (symbol) { return symbol === unknownSymbol; },
+            getMergedSymbol: getMergedSymbol,
+            getDiagnostics: getDiagnostics,
+            getGlobalDiagnostics: getGlobalDiagnostics,
+            getTypeOfSymbolAtLocation: function (symbol, location) {
+                location = ts.getParseTreeNode(location);
+                return location ? getTypeOfSymbolAtLocation(symbol, location) : errorType;
+            },
+            getSymbolsOfParameterPropertyDeclaration: function (parameterIn, parameterName) {
+                var parameter = ts.getParseTreeNode(parameterIn, ts.isParameter);
+                if (parameter === undefined)
+                    return ts.Debug.fail("Cannot get symbols of a synthetic parameter that cannot be resolved to a parse-tree node.");
+                return getSymbolsOfParameterPropertyDeclaration(parameter, ts.escapeLeadingUnderscores(parameterName));
+            },
+            getDeclaredTypeOfSymbol: getDeclaredTypeOfSymbol,
+            getPropertiesOfType: getPropertiesOfType,
+            getPropertyOfType: function (type, name) { return getPropertyOfType(type, ts.escapeLeadingUnderscores(name)); },
+            getIndexInfoOfType: getIndexInfoOfType,
+            getSignaturesOfType: getSignaturesOfType,
+            getIndexTypeOfType: getIndexTypeOfType,
+            getBaseTypes: getBaseTypes,
+            getBaseTypeOfLiteralType: getBaseTypeOfLiteralType,
+            getWidenedType: getWidenedType,
+            getTypeFromTypeNode: function (nodeIn) {
+                var node = ts.getParseTreeNode(nodeIn, ts.isTypeNode);
+                return node ? getTypeFromTypeNode(node) : errorType;
+            },
+            getParameterType: getTypeAtPosition,
+            getReturnTypeOfSignature: getReturnTypeOfSignature,
+            getNullableType: getNullableType,
+            getNonNullableType: getNonNullableType,
+            typeToTypeNode: nodeBuilder.typeToTypeNode,
+            indexInfoToIndexSignatureDeclaration: nodeBuilder.indexInfoToIndexSignatureDeclaration,
+            signatureToSignatureDeclaration: nodeBuilder.signatureToSignatureDeclaration,
+            symbolToEntityName: nodeBuilder.symbolToEntityName,
+            symbolToExpression: nodeBuilder.symbolToExpression,
+            symbolToTypeParameterDeclarations: nodeBuilder.symbolToTypeParameterDeclarations,
+            symbolToParameterDeclaration: nodeBuilder.symbolToParameterDeclaration,
+            typeParameterToDeclaration: nodeBuilder.typeParameterToDeclaration,
+            getSymbolsInScope: function (location, meaning) {
+                location = ts.getParseTreeNode(location);
+                return location ? getSymbolsInScope(location, meaning) : [];
+            },
+            getSymbolAtLocation: function (node) {
+                node = ts.getParseTreeNode(node);
+                return node ? getSymbolAtLocation(node) : undefined;
+            },
+            getShorthandAssignmentValueSymbol: function (node) {
+                node = ts.getParseTreeNode(node);
+                return node ? getShorthandAssignmentValueSymbol(node) : undefined;
+            },
+            getExportSpecifierLocalTargetSymbol: function (nodeIn) {
+                var node = ts.getParseTreeNode(nodeIn, ts.isExportSpecifier);
+                return node ? getExportSpecifierLocalTargetSymbol(node) : undefined;
+            },
+            getExportSymbolOfSymbol: function (symbol) {
+                return getMergedSymbol(symbol.exportSymbol || symbol);
+            },
+            getTypeAtLocation: function (node) {
+                node = ts.getParseTreeNode(node);
+                return node ? getTypeOfNode(node) : errorType;
+            },
+            getPropertySymbolOfDestructuringAssignment: function (locationIn) {
+                var location = ts.getParseTreeNode(locationIn, ts.isIdentifier);
+                return location ? getPropertySymbolOfDestructuringAssignment(location) : undefined;
+            },
+            signatureToString: function (signature, enclosingDeclaration, flags, kind) {
+                return signatureToString(signature, ts.getParseTreeNode(enclosingDeclaration), flags, kind);
+            },
+            typeToString: function (type, enclosingDeclaration, flags) {
+                return typeToString(type, ts.getParseTreeNode(enclosingDeclaration), flags);
+            },
+            symbolToString: function (symbol, enclosingDeclaration, meaning, flags) {
+                return symbolToString(symbol, ts.getParseTreeNode(enclosingDeclaration), meaning, flags);
+            },
+            typePredicateToString: function (predicate, enclosingDeclaration, flags) {
+                return typePredicateToString(predicate, ts.getParseTreeNode(enclosingDeclaration), flags);
+            },
+            writeSignature: function (signature, enclosingDeclaration, flags, kind, writer) {
+                return signatureToString(signature, ts.getParseTreeNode(enclosingDeclaration), flags, kind, writer);
+            },
+            writeType: function (type, enclosingDeclaration, flags, writer) {
+                return typeToString(type, ts.getParseTreeNode(enclosingDeclaration), flags, writer);
+            },
+            writeSymbol: function (symbol, enclosingDeclaration, meaning, flags, writer) {
+                return symbolToString(symbol, ts.getParseTreeNode(enclosingDeclaration), meaning, flags, writer);
+            },
+            writeTypePredicate: function (predicate, enclosingDeclaration, flags, writer) {
+                return typePredicateToString(predicate, ts.getParseTreeNode(enclosingDeclaration), flags, writer);
+            },
+            getSymbolDisplayBuilder: getSymbolDisplayBuilder,
+            getAugmentedPropertiesOfType: getAugmentedPropertiesOfType,
+            getRootSymbols: getRootSymbols,
+            getContextualType: function (nodeIn) {
+                var node = ts.getParseTreeNode(nodeIn, ts.isExpression);
+                return node ? getContextualType(node) : undefined;
+            },
+            getContextualTypeForArgumentAtIndex: function (nodeIn, argIndex) {
+                var node = ts.getParseTreeNode(nodeIn, ts.isCallLikeExpression);
+                return node && getContextualTypeForArgumentAtIndex(node, argIndex);
+            },
+            getContextualTypeForJsxAttribute: function (nodeIn) {
+                var node = ts.getParseTreeNode(nodeIn, ts.isJsxAttributeLike);
+                return node && getContextualTypeForJsxAttribute(node);
+            },
+            isContextSensitive: isContextSensitive,
+            getFullyQualifiedName: getFullyQualifiedName,
+            getResolvedSignature: function (nodeIn, candidatesOutArray, theArgumentCount) {
+                var node = ts.getParseTreeNode(nodeIn, ts.isCallLikeExpression);
+                apparentArgumentCount = theArgumentCount;
+                var res = node ? getResolvedSignature(node, candidatesOutArray) : undefined;
+                apparentArgumentCount = undefined;
+                return res;
+            },
+            getConstantValue: function (nodeIn) {
+                var node = ts.getParseTreeNode(nodeIn, canHaveConstantValue);
+                return node ? getConstantValue(node) : undefined;
+            },
+            isValidPropertyAccess: function (nodeIn, propertyName) {
+                var node = ts.getParseTreeNode(nodeIn, ts.isPropertyAccessOrQualifiedNameOrImportTypeNode);
+                return !!node && isValidPropertyAccess(node, ts.escapeLeadingUnderscores(propertyName));
+            },
+            isValidPropertyAccessForCompletions: function (nodeIn, type, property) {
+                var node = ts.getParseTreeNode(nodeIn, ts.isPropertyAccessExpression);
+                return !!node && isValidPropertyAccessForCompletions(node, type, property);
+            },
+            getSignatureFromDeclaration: function (declarationIn) {
+                var declaration = ts.getParseTreeNode(declarationIn, ts.isFunctionLike);
+                return declaration ? getSignatureFromDeclaration(declaration) : undefined;
+            },
+            isImplementationOfOverload: function (node) {
+                var parsed = ts.getParseTreeNode(node, ts.isFunctionLike);
+                return parsed ? isImplementationOfOverload(parsed) : undefined;
+            },
+            getImmediateAliasedSymbol: function (symbol) {
+                ts.Debug.assert((symbol.flags & 2097152 /* Alias */) !== 0, "Should only get Alias here.");
+                var links = getSymbolLinks(symbol);
+                if (!links.immediateTarget) {
+                    var node = getDeclarationOfAliasSymbol(symbol);
+                    if (!node)
+                        return ts.Debug.fail();
+                    links.immediateTarget = getTargetOfAliasDeclaration(node, /*dontRecursivelyResolve*/ true);
+                }
+                return links.immediateTarget;
+            },
+            getAliasedSymbol: resolveAlias,
+            getEmitResolver: getEmitResolver,
+            getExportsOfModule: getExportsOfModuleAsArray,
+            getExportsAndPropertiesOfModule: getExportsAndPropertiesOfModule,
+            getSymbolWalker: ts.createGetSymbolWalker(getRestTypeOfSignature, getTypePredicateOfSignature, getReturnTypeOfSignature, getBaseTypes, resolveStructuredTypeMembers, getTypeOfSymbol, getResolvedSymbol, getIndexTypeOfStructuredType, getConstraintFromTypeParameter, getFirstIdentifier),
+            getAmbientModules: getAmbientModules,
+            getAllAttributesTypeFromJsxOpeningLikeElement: function (nodeIn) {
+                var node = ts.getParseTreeNode(nodeIn, ts.isJsxOpeningLikeElement);
+                return node ? getAllAttributesTypeFromJsxOpeningLikeElement(node) : undefined;
+            },
+            getJsxIntrinsicTagNamesAt: getJsxIntrinsicTagNamesAt,
+            isOptionalParameter: function (nodeIn) {
+                var node = ts.getParseTreeNode(nodeIn, ts.isParameter);
+                return node ? isOptionalParameter(node) : false;
+            },
+            tryGetMemberInModuleExports: function (name, symbol) { return tryGetMemberInModuleExports(ts.escapeLeadingUnderscores(name), symbol); },
+            tryGetMemberInModuleExportsAndProperties: function (name, symbol) { return tryGetMemberInModuleExportsAndProperties(ts.escapeLeadingUnderscores(name), symbol); },
+            tryFindAmbientModuleWithoutAugmentations: function (moduleName) {
+                // we deliberately exclude augmentations
+                // since we are only interested in declarations of the module itself
+                return tryFindAmbientModule(moduleName, /*withAugmentations*/ false);
+            },
+            getApparentType: getApparentType,
+            getUnionType: getUnionType,
+            createAnonymousType: createAnonymousType,
+            createSignature: createSignature,
+            createSymbol: createSymbol,
+            createIndexInfo: createIndexInfo,
+            getAnyType: function () { return anyType; },
+            getStringType: function () { return stringType; },
+            getNumberType: function () { return numberType; },
+            createPromiseType: createPromiseType,
+            createArrayType: createArrayType,
+            getBooleanType: function () { return booleanType; },
+            getFalseType: function () { return falseType; },
+            getTrueType: function () { return trueType; },
+            getVoidType: function () { return voidType; },
+            getUndefinedType: function () { return undefinedType; },
+            getNullType: function () { return nullType; },
+            getESSymbolType: function () { return esSymbolType; },
+            getNeverType: function () { return neverType; },
+            isSymbolAccessible: isSymbolAccessible,
+            isArrayLikeType: isArrayLikeType,
+            getAllPossiblePropertiesOfTypes: getAllPossiblePropertiesOfTypes,
+            getSuggestionForNonexistentProperty: function (node, type) { return getSuggestionForNonexistentProperty(node, type); },
+            getSuggestionForNonexistentSymbol: function (location, name, meaning) { return getSuggestionForNonexistentSymbol(location, ts.escapeLeadingUnderscores(name), meaning); },
+            getSuggestionForNonexistentModule: function (node, target) { return getSuggestionForNonexistentModule(node, target); },
+            getBaseConstraintOfType: getBaseConstraintOfType,
+            getDefaultFromTypeParameter: function (type) { return type && type.flags & 65536 /* TypeParameter */ ? getDefaultFromTypeParameter(type) : undefined; },
+            resolveName: function (name, location, meaning, excludeGlobals) {
+                return resolveName(location, ts.escapeLeadingUnderscores(name), meaning, /*nameNotFoundMessage*/ undefined, /*nameArg*/ undefined, /*isUse*/ false, excludeGlobals);
+            },
+            getJsxNamespace: function (n) { return ts.unescapeLeadingUnderscores(getJsxNamespace(n)); },
+            getAccessibleSymbolChain: getAccessibleSymbolChain,
+            getTypePredicateOfSignature: getTypePredicateOfSignature,
+            resolveExternalModuleSymbol: resolveExternalModuleSymbol,
+            tryGetThisTypeAt: function (node) {
+                node = ts.getParseTreeNode(node);
+                return node && tryGetThisTypeAt(node);
+            },
+            getTypeArgumentConstraint: function (nodeIn) {
+                var node = ts.getParseTreeNode(nodeIn, ts.isTypeNode);
+                return node && getTypeArgumentConstraint(node);
+            },
+            getSuggestionDiagnostics: function (file, ct) {
+                var diagnostics;
+                try {
+                    // Record the cancellation token so it can be checked later on during checkSourceElement.
+                    // Do this in a finally block so we can ensure that it gets reset back to nothing after
+                    // this call is done.
+                    cancellationToken = ct;
+                    // Ensure file is type checked
+                    checkSourceFile(file);
+                    ts.Debug.assert(!!(getNodeLinks(file).flags & 1 /* TypeChecked */));
+                    diagnostics = ts.addRange(diagnostics, suggestionDiagnostics.get(file.fileName));
+                    if (!file.isDeclarationFile && (!unusedIsError(0 /* Local */) || !unusedIsError(1 /* Parameter */))) {
+                        addUnusedDiagnostics();
+                    }
+                    return diagnostics || ts.emptyArray;
+                }
+                finally {
+                    cancellationToken = undefined;
+                }
+                function addUnusedDiagnostics() {
+                    checkUnusedIdentifiers(getPotentiallyUnusedIdentifiers(file), function (kind, diag) {
+                        if (!unusedIsError(kind)) {
+                            (diagnostics || (diagnostics = [])).push(__assign({}, diag, { category: ts.DiagnosticCategory.Suggestion }));
+                        }
+                    });
+                }
+            },
+            runWithCancellationToken: function (token, callback) {
+                try {
+                    cancellationToken = token;
+                    return callback(checker);
+                }
+                finally {
+                    cancellationToken = undefined;
+                }
+            }
+        };
+        var tupleTypes = [];
+        var unionTypes = ts.createMap();
+        var intersectionTypes = ts.createMap();
+        var literalTypes = ts.createMap();
+        var indexedAccessTypes = ts.createMap();
+        var evolvingArrayTypes = [];
+        var undefinedProperties = ts.createMap();
+        var unknownSymbol = createSymbol(4 /* Property */, "unknown");
+        var resolvingSymbol = createSymbol(0, "__resolving__" /* Resolving */);
+        var anyType = createIntrinsicType(1 /* Any */, "any");
+        var autoType = createIntrinsicType(1 /* Any */, "any");
+        var wildcardType = createIntrinsicType(1 /* Any */, "any");
+        var errorType = createIntrinsicType(1 /* Any */, "error");
+        var unknownType = createIntrinsicType(2 /* Unknown */, "unknown");
+        var undefinedType = createIntrinsicType(8192 /* Undefined */, "undefined");
+        var undefinedWideningType = strictNullChecks ? undefinedType : createIntrinsicType(8192 /* Undefined */ | 134217728 /* ContainsWideningType */, "undefined");
+        var nullType = createIntrinsicType(16384 /* Null */, "null");
+        var nullWideningType = strictNullChecks ? nullType : createIntrinsicType(16384 /* Null */ | 134217728 /* ContainsWideningType */, "null");
+        var stringType = createIntrinsicType(4 /* String */, "string");
+        var numberType = createIntrinsicType(8 /* Number */, "number");
+        var falseType = createIntrinsicType(256 /* BooleanLiteral */, "false");
+        var trueType = createIntrinsicType(256 /* BooleanLiteral */, "true");
+        var booleanType = createBooleanType([falseType, trueType]);
+        var esSymbolType = createIntrinsicType(1024 /* ESSymbol */, "symbol");
+        var voidType = createIntrinsicType(4096 /* Void */, "void");
+        var neverType = createIntrinsicType(32768 /* Never */, "never");
+        var silentNeverType = createIntrinsicType(32768 /* Never */, "never");
+        var implicitNeverType = createIntrinsicType(32768 /* Never */, "never");
+        var nonPrimitiveType = createIntrinsicType(16777216 /* NonPrimitive */, "object");
+        var stringNumberSymbolType = getUnionType([stringType, numberType, esSymbolType]);
+        var keyofConstraintType = keyofStringsOnly ? stringType : stringNumberSymbolType;
+        var emptyObjectType = createAnonymousType(undefined, emptySymbols, ts.emptyArray, ts.emptyArray, undefined, undefined);
+        var emptyTypeLiteralSymbol = createSymbol(2048 /* TypeLiteral */, "__type" /* Type */);
+        emptyTypeLiteralSymbol.members = ts.createSymbolTable();
+        var emptyTypeLiteralType = createAnonymousType(emptyTypeLiteralSymbol, emptySymbols, ts.emptyArray, ts.emptyArray, undefined, undefined);
+        var emptyGenericType = createAnonymousType(undefined, emptySymbols, ts.emptyArray, ts.emptyArray, undefined, undefined);
+        emptyGenericType.instantiations = ts.createMap();
+        var anyFunctionType = createAnonymousType(undefined, emptySymbols, ts.emptyArray, ts.emptyArray, undefined, undefined);
+        // The anyFunctionType contains the anyFunctionType by definition. The flag is further propagated
+        // in getPropagatingFlagsOfTypes, and it is checked in inferFromTypes.
+        anyFunctionType.flags |= 536870912 /* ContainsAnyFunctionType */;
+        var noConstraintType = createAnonymousType(undefined, emptySymbols, ts.emptyArray, ts.emptyArray, undefined, undefined);
+        var circularConstraintType = createAnonymousType(undefined, emptySymbols, ts.emptyArray, ts.emptyArray, undefined, undefined);
+        var resolvingDefaultType = createAnonymousType(undefined, emptySymbols, ts.emptyArray, ts.emptyArray, undefined, undefined);
+        var markerSuperType = createType(65536 /* TypeParameter */);
+        var markerSubType = createType(65536 /* TypeParameter */);
+        markerSubType.constraint = markerSuperType;
+        var markerOtherType = createType(65536 /* TypeParameter */);
+        var noTypePredicate = createIdentifierTypePredicate("<<unresolved>>", 0, anyType);
+        var anySignature = createSignature(undefined, undefined, undefined, ts.emptyArray, anyType, /*resolvedTypePredicate*/ undefined, 0, /*hasRestParameter*/ false, /*hasLiteralTypes*/ false);
+        var unknownSignature = createSignature(undefined, undefined, undefined, ts.emptyArray, errorType, /*resolvedTypePredicate*/ undefined, 0, /*hasRestParameter*/ false, /*hasLiteralTypes*/ false);
+        var resolvingSignature = createSignature(undefined, undefined, undefined, ts.emptyArray, anyType, /*resolvedTypePredicate*/ undefined, 0, /*hasRestParameter*/ false, /*hasLiteralTypes*/ false);
+        var silentNeverSignature = createSignature(undefined, undefined, undefined, ts.emptyArray, silentNeverType, /*resolvedTypePredicate*/ undefined, 0, /*hasRestParameter*/ false, /*hasLiteralTypes*/ false);
+        var resolvingSignaturesArray = [resolvingSignature];
+        var enumNumberIndexInfo = createIndexInfo(stringType, /*isReadonly*/ true);
+        var jsObjectLiteralIndexInfo = createIndexInfo(anyType, /*isReadonly*/ false);
+        var globals = ts.createSymbolTable();
+        var reverseMappedCache = ts.createMap();
+        var ambientModulesCache;
+        /**
+         * List of every ambient module with a "*" wildcard.
+         * Unlike other ambient modules, these can't be stored in `globals` because symbol tables only deal with exact matches.
+         * This is only used if there is no exact match.
+         */
+        var patternAmbientModules;
+        var globalObjectType;
+        var globalFunctionType;
+        var globalArrayType;
+        var globalReadonlyArrayType;
+        var globalStringType;
+        var globalNumberType;
+        var globalBooleanType;
+        var globalRegExpType;
+        var globalThisType;
+        var anyArrayType;
+        var autoArrayType;
+        var anyReadonlyArrayType;
+        var deferredGlobalNonNullableTypeAlias;
+        // The library files are only loaded when the feature is used.
+        // This allows users to just specify library files they want to used through --lib
+        // and they will not get an error from not having unrelated library files
+        var deferredGlobalESSymbolConstructorSymbol;
+        var deferredGlobalESSymbolType;
+        var deferredGlobalTypedPropertyDescriptorType;
+        var deferredGlobalPromiseType;
+        var deferredGlobalPromiseConstructorSymbol;
+        var deferredGlobalPromiseConstructorLikeType;
+        var deferredGlobalIterableType;
+        var deferredGlobalIteratorType;
+        var deferredGlobalIterableIteratorType;
+        var deferredGlobalAsyncIterableType;
+        var deferredGlobalAsyncIteratorType;
+        var deferredGlobalAsyncIterableIteratorType;
+        var deferredGlobalTemplateStringsArrayType;
+        var deferredGlobalImportMetaType;
+        var deferredGlobalExtractSymbol;
+        var deferredNodes;
+        var allPotentiallyUnusedIdentifiers = ts.createMap(); // key is file name
+        var flowLoopStart = 0;
+        var flowLoopCount = 0;
+        var sharedFlowCount = 0;
+        var flowAnalysisDisabled = false;
+        var emptyStringType = getLiteralType("");
+        var zeroType = getLiteralType(0);
+        var resolutionTargets = [];
+        var resolutionResults = [];
+        var resolutionPropertyNames = [];
+        var suggestionCount = 0;
+        var maximumSuggestionCount = 10;
+        var mergedSymbols = [];
+        var symbolLinks = [];
+        var nodeLinks = [];
+        var flowLoopCaches = [];
+        var flowLoopNodes = [];
+        var flowLoopKeys = [];
+        var flowLoopTypes = [];
+        var sharedFlowNodes = [];
+        var sharedFlowTypes = [];
+        var potentialThisCollisions = [];
+        var potentialNewTargetCollisions = [];
+        var awaitedTypeStack = [];
+        var diagnostics = ts.createDiagnosticCollection();
+        // Suggestion diagnostics must have a file. Keyed by source file name.
+        var suggestionDiagnostics = ts.createMultiMap();
+        var TypeFacts;
+        (function (TypeFacts) {
+            TypeFacts[TypeFacts["None"] = 0] = "None";
+            TypeFacts[TypeFacts["TypeofEQString"] = 1] = "TypeofEQString";
+            TypeFacts[TypeFacts["TypeofEQNumber"] = 2] = "TypeofEQNumber";
+            TypeFacts[TypeFacts["TypeofEQBoolean"] = 4] = "TypeofEQBoolean";
+            TypeFacts[TypeFacts["TypeofEQSymbol"] = 8] = "TypeofEQSymbol";
+            TypeFacts[TypeFacts["TypeofEQObject"] = 16] = "TypeofEQObject";
+            TypeFacts[TypeFacts["TypeofEQFunction"] = 32] = "TypeofEQFunction";
+            TypeFacts[TypeFacts["TypeofEQHostObject"] = 64] = "TypeofEQHostObject";
+            TypeFacts[TypeFacts["TypeofNEString"] = 128] = "TypeofNEString";
+            TypeFacts[TypeFacts["TypeofNENumber"] = 256] = "TypeofNENumber";
+            TypeFacts[TypeFacts["TypeofNEBoolean"] = 512] = "TypeofNEBoolean";
+            TypeFacts[TypeFacts["TypeofNESymbol"] = 1024] = "TypeofNESymbol";
+            TypeFacts[TypeFacts["TypeofNEObject"] = 2048] = "TypeofNEObject";
+            TypeFacts[TypeFacts["TypeofNEFunction"] = 4096] = "TypeofNEFunction";
+            TypeFacts[TypeFacts["TypeofNEHostObject"] = 8192] = "TypeofNEHostObject";
+            TypeFacts[TypeFacts["EQUndefined"] = 16384] = "EQUndefined";
+            TypeFacts[TypeFacts["EQNull"] = 32768] = "EQNull";
+            TypeFacts[TypeFacts["EQUndefinedOrNull"] = 65536] = "EQUndefinedOrNull";
+            TypeFacts[TypeFacts["NEUndefined"] = 131072] = "NEUndefined";
+            TypeFacts[TypeFacts["NENull"] = 262144] = "NENull";
+            TypeFacts[TypeFacts["NEUndefinedOrNull"] = 524288] = "NEUndefinedOrNull";
+            TypeFacts[TypeFacts["Truthy"] = 1048576] = "Truthy";
+            TypeFacts[TypeFacts["Falsy"] = 2097152] = "Falsy";
+            TypeFacts[TypeFacts["All"] = 4194303] = "All";
+            // The following members encode facts about particular kinds of types for use in the getTypeFacts function.
+            // The presence of a particular fact means that the given test is true for some (and possibly all) values
+            // of that kind of type.
+            TypeFacts[TypeFacts["BaseStringStrictFacts"] = 933633] = "BaseStringStrictFacts";
+            TypeFacts[TypeFacts["BaseStringFacts"] = 3145473] = "BaseStringFacts";
+            TypeFacts[TypeFacts["StringStrictFacts"] = 4079361] = "StringStrictFacts";
+            TypeFacts[TypeFacts["StringFacts"] = 4194049] = "StringFacts";
+            TypeFacts[TypeFacts["EmptyStringStrictFacts"] = 3030785] = "EmptyStringStrictFacts";
+            TypeFacts[TypeFacts["EmptyStringFacts"] = 3145473] = "EmptyStringFacts";
+            TypeFacts[TypeFacts["NonEmptyStringStrictFacts"] = 1982209] = "NonEmptyStringStrictFacts";
+            TypeFacts[TypeFacts["NonEmptyStringFacts"] = 4194049] = "NonEmptyStringFacts";
+            TypeFacts[TypeFacts["BaseNumberStrictFacts"] = 933506] = "BaseNumberStrictFacts";
+            TypeFacts[TypeFacts["BaseNumberFacts"] = 3145346] = "BaseNumberFacts";
+            TypeFacts[TypeFacts["NumberStrictFacts"] = 4079234] = "NumberStrictFacts";
+            TypeFacts[TypeFacts["NumberFacts"] = 4193922] = "NumberFacts";
+            TypeFacts[TypeFacts["ZeroStrictFacts"] = 3030658] = "ZeroStrictFacts";
+            TypeFacts[TypeFacts["ZeroFacts"] = 3145346] = "ZeroFacts";
+            TypeFacts[TypeFacts["NonZeroStrictFacts"] = 1982082] = "NonZeroStrictFacts";
+            TypeFacts[TypeFacts["NonZeroFacts"] = 4193922] = "NonZeroFacts";
+            TypeFacts[TypeFacts["BaseBooleanStrictFacts"] = 933252] = "BaseBooleanStrictFacts";
+            TypeFacts[TypeFacts["BaseBooleanFacts"] = 3145092] = "BaseBooleanFacts";
+            TypeFacts[TypeFacts["BooleanStrictFacts"] = 4078980] = "BooleanStrictFacts";
+            TypeFacts[TypeFacts["BooleanFacts"] = 4193668] = "BooleanFacts";
+            TypeFacts[TypeFacts["FalseStrictFacts"] = 3030404] = "FalseStrictFacts";
+            TypeFacts[TypeFacts["FalseFacts"] = 3145092] = "FalseFacts";
+            TypeFacts[TypeFacts["TrueStrictFacts"] = 1981828] = "TrueStrictFacts";
+            TypeFacts[TypeFacts["TrueFacts"] = 4193668] = "TrueFacts";
+            TypeFacts[TypeFacts["SymbolStrictFacts"] = 1981320] = "SymbolStrictFacts";
+            TypeFacts[TypeFacts["SymbolFacts"] = 4193160] = "SymbolFacts";
+            TypeFacts[TypeFacts["ObjectStrictFacts"] = 1972176] = "ObjectStrictFacts";
+            TypeFacts[TypeFacts["ObjectFacts"] = 4184016] = "ObjectFacts";
+            TypeFacts[TypeFacts["FunctionStrictFacts"] = 1970144] = "FunctionStrictFacts";
+            TypeFacts[TypeFacts["FunctionFacts"] = 4181984] = "FunctionFacts";
+            TypeFacts[TypeFacts["UndefinedFacts"] = 2457472] = "UndefinedFacts";
+            TypeFacts[TypeFacts["NullFacts"] = 2340752] = "NullFacts";
+        })(TypeFacts || (TypeFacts = {}));
+        var typeofEQFacts = ts.createMapFromTemplate({
+            string: 1 /* TypeofEQString */,
+            number: 2 /* TypeofEQNumber */,
+            boolean: 4 /* TypeofEQBoolean */,
+            symbol: 8 /* TypeofEQSymbol */,
+            undefined: 16384 /* EQUndefined */,
+            object: 16 /* TypeofEQObject */,
+            function: 32 /* TypeofEQFunction */
+        });
+        var typeofNEFacts = ts.createMapFromTemplate({
+            string: 128 /* TypeofNEString */,
+            number: 256 /* TypeofNENumber */,
+            boolean: 512 /* TypeofNEBoolean */,
+            symbol: 1024 /* TypeofNESymbol */,
+            undefined: 131072 /* NEUndefined */,
+            object: 2048 /* TypeofNEObject */,
+            function: 4096 /* TypeofNEFunction */
+        });
+        var typeofTypesByName = ts.createMapFromTemplate({
+            string: stringType,
+            number: numberType,
+            boolean: booleanType,
+            symbol: esSymbolType,
+            undefined: undefinedType
+        });
+        var typeofType = createTypeofType();
+        var _jsxNamespace;
+        var _jsxFactoryEntity;
+        var subtypeRelation = ts.createMap();
+        var assignableRelation = ts.createMap();
+        var definitelyAssignableRelation = ts.createMap();
+        var comparableRelation = ts.createMap();
+        var identityRelation = ts.createMap();
+        var enumRelation = ts.createMap();
+        var TypeSystemPropertyName;
+        (function (TypeSystemPropertyName) {
+            TypeSystemPropertyName[TypeSystemPropertyName["Type"] = 0] = "Type";
+            TypeSystemPropertyName[TypeSystemPropertyName["ResolvedBaseConstructorType"] = 1] = "ResolvedBaseConstructorType";
+            TypeSystemPropertyName[TypeSystemPropertyName["DeclaredType"] = 2] = "DeclaredType";
+            TypeSystemPropertyName[TypeSystemPropertyName["ResolvedReturnType"] = 3] = "ResolvedReturnType";
+            TypeSystemPropertyName[TypeSystemPropertyName["ResolvedBaseConstraint"] = 4] = "ResolvedBaseConstraint";
+        })(TypeSystemPropertyName || (TypeSystemPropertyName = {}));
+        var CheckMode;
+        (function (CheckMode) {
+            CheckMode[CheckMode["Normal"] = 0] = "Normal";
+            CheckMode[CheckMode["SkipContextSensitive"] = 1] = "SkipContextSensitive";
+            CheckMode[CheckMode["Inferential"] = 2] = "Inferential";
+            CheckMode[CheckMode["Contextual"] = 3] = "Contextual";
+        })(CheckMode || (CheckMode = {}));
+        var CallbackCheck;
+        (function (CallbackCheck) {
+            CallbackCheck[CallbackCheck["None"] = 0] = "None";
+            CallbackCheck[CallbackCheck["Bivariant"] = 1] = "Bivariant";
+            CallbackCheck[CallbackCheck["Strict"] = 2] = "Strict";
+        })(CallbackCheck || (CallbackCheck = {}));
+        var MappedTypeModifiers;
+        (function (MappedTypeModifiers) {
+            MappedTypeModifiers[MappedTypeModifiers["IncludeReadonly"] = 1] = "IncludeReadonly";
+            MappedTypeModifiers[MappedTypeModifiers["ExcludeReadonly"] = 2] = "ExcludeReadonly";
+            MappedTypeModifiers[MappedTypeModifiers["IncludeOptional"] = 4] = "IncludeOptional";
+            MappedTypeModifiers[MappedTypeModifiers["ExcludeOptional"] = 8] = "ExcludeOptional";
+        })(MappedTypeModifiers || (MappedTypeModifiers = {}));
+        var ExpandingFlags;
+        (function (ExpandingFlags) {
+            ExpandingFlags[ExpandingFlags["None"] = 0] = "None";
+            ExpandingFlags[ExpandingFlags["Source"] = 1] = "Source";
+            ExpandingFlags[ExpandingFlags["Target"] = 2] = "Target";
+            ExpandingFlags[ExpandingFlags["Both"] = 3] = "Both";
+        })(ExpandingFlags || (ExpandingFlags = {}));
+        var MembersOrExportsResolutionKind;
+        (function (MembersOrExportsResolutionKind) {
+            MembersOrExportsResolutionKind["resolvedExports"] = "resolvedExports";
+            MembersOrExportsResolutionKind["resolvedMembers"] = "resolvedMembers";
+        })(MembersOrExportsResolutionKind || (MembersOrExportsResolutionKind = {}));
+        var UnusedKind;
+        (function (UnusedKind) {
+            UnusedKind[UnusedKind["Local"] = 0] = "Local";
+            UnusedKind[UnusedKind["Parameter"] = 1] = "Parameter";
+        })(UnusedKind || (UnusedKind = {}));
+        var builtinGlobals = ts.createSymbolTable();
+        builtinGlobals.set(undefinedSymbol.escapedName, undefinedSymbol);
+        var isNotOverloadAndNotAccessor = ts.and(isNotOverload, isNotAccessor);
+        initializeTypeChecker();
+        return checker;
+        /**
+         * @deprecated
+         */
+        function getSymbolDisplayBuilder() {
+            return {
+                buildTypeDisplay: function (type, writer, enclosingDeclaration, flags) {
+                    typeToString(type, enclosingDeclaration, flags, emitTextWriterWrapper(writer));
+                },
+                buildSymbolDisplay: function (symbol, writer, enclosingDeclaration, meaning, flags) {
+                    if (flags === void 0) { flags = 0 /* None */; }
+                    symbolToString(symbol, enclosingDeclaration, meaning, flags | 4 /* AllowAnyNodeKind */, emitTextWriterWrapper(writer));
+                },
+                buildSignatureDisplay: function (signature, writer, enclosing, flags, kind) {
+                    signatureToString(signature, enclosing, flags, kind, emitTextWriterWrapper(writer));
+                },
+                buildIndexSignatureDisplay: function (info, writer, kind, enclosing, flags) {
+                    var sig = nodeBuilder.indexInfoToIndexSignatureDeclaration(info, kind, enclosing, toNodeBuilderFlags(flags) | 3112960 /* IgnoreErrors */, writer);
+                    var printer = ts.createPrinter({ removeComments: true });
+                    printer.writeNode(4 /* Unspecified */, sig, ts.getSourceFileOfNode(ts.getParseTreeNode(enclosing)), emitTextWriterWrapper(writer));
+                },
+                buildParameterDisplay: function (symbol, writer, enclosing, flags) {
+                    var node = nodeBuilder.symbolToParameterDeclaration(symbol, enclosing, toNodeBuilderFlags(flags) | 3112960 /* IgnoreErrors */, writer);
+                    var printer = ts.createPrinter({ removeComments: true });
+                    printer.writeNode(4 /* Unspecified */, node, ts.getSourceFileOfNode(ts.getParseTreeNode(enclosing)), emitTextWriterWrapper(writer)); // TODO: GH#18217
+                },
+                buildTypeParameterDisplay: function (tp, writer, enclosing, flags) {
+                    var node = nodeBuilder.typeParameterToDeclaration(tp, enclosing, toNodeBuilderFlags(flags) | 3112960 /* IgnoreErrors */ | 8192 /* OmitParameterModifiers */, writer);
+                    var printer = ts.createPrinter({ removeComments: true });
+                    printer.writeNode(4 /* Unspecified */, node, ts.getSourceFileOfNode(ts.getParseTreeNode(enclosing)), emitTextWriterWrapper(writer)); // TODO: GH#18217
+                },
+                buildTypePredicateDisplay: function (predicate, writer, enclosing, flags) {
+                    typePredicateToString(predicate, enclosing, flags, emitTextWriterWrapper(writer));
+                },
+                buildTypeParameterDisplayFromSymbol: function (symbol, writer, enclosing, flags) {
+                    var nodes = nodeBuilder.symbolToTypeParameterDeclarations(symbol, enclosing, toNodeBuilderFlags(flags) | 3112960 /* IgnoreErrors */, writer);
+                    var printer = ts.createPrinter({ removeComments: true });
+                    printer.writeList(26896 /* TypeParameters */, nodes, ts.getSourceFileOfNode(ts.getParseTreeNode(enclosing)), emitTextWriterWrapper(writer));
+                },
+                buildDisplayForParametersAndDelimiters: function (thisParameter, parameters, writer, enclosing, originalFlags) {
+                    var printer = ts.createPrinter({ removeComments: true });
+                    var flags = 8192 /* OmitParameterModifiers */ | 3112960 /* IgnoreErrors */ | toNodeBuilderFlags(originalFlags);
+                    var thisParameterArray = thisParameter ? [nodeBuilder.symbolToParameterDeclaration(thisParameter, enclosing, flags)] : []; // TODO: GH#18217
+                    var params = ts.createNodeArray(thisParameterArray.concat(ts.map(parameters, function (param) { return nodeBuilder.symbolToParameterDeclaration(param, enclosing, flags); }))); // TODO: GH#18217
+                    printer.writeList(1296 /* CallExpressionArguments */, params, ts.getSourceFileOfNode(ts.getParseTreeNode(enclosing)), emitTextWriterWrapper(writer));
+                },
+                buildDisplayForTypeParametersAndDelimiters: function (typeParameters, writer, enclosing, flags) {
+                    var printer = ts.createPrinter({ removeComments: true });
+                    var args = ts.createNodeArray(ts.map(typeParameters, function (p) { return nodeBuilder.typeParameterToDeclaration(p, enclosing, toNodeBuilderFlags(flags)); })); // TODO: GH#18217
+                    printer.writeList(26896 /* TypeParameters */, args, ts.getSourceFileOfNode(ts.getParseTreeNode(enclosing)), emitTextWriterWrapper(writer));
+                },
+                buildReturnTypeDisplay: function (signature, writer, enclosing, flags) {
+                    writer.writePunctuation(":");
+                    writer.writeSpace(" ");
+                    var predicate = getTypePredicateOfSignature(signature);
+                    if (predicate) {
+                        return typePredicateToString(predicate, enclosing, flags, emitTextWriterWrapper(writer));
+                    }
+                    var node = nodeBuilder.typeToTypeNode(getReturnTypeOfSignature(signature), enclosing, toNodeBuilderFlags(flags) | 3112960 /* IgnoreErrors */, writer);
+                    var printer = ts.createPrinter({ removeComments: true });
+                    printer.writeNode(4 /* Unspecified */, node, ts.getSourceFileOfNode(ts.getParseTreeNode(enclosing)), emitTextWriterWrapper(writer)); // TODO: GH#18217
+                }
+            };
+            function emitTextWriterWrapper(underlying) {
+                return {
+                    write: ts.noop,
+                    writeTextOfNode: ts.noop,
+                    writeLine: ts.noop,
+                    increaseIndent: function () {
+                        return underlying.increaseIndent();
+                    },
+                    decreaseIndent: function () {
+                        return underlying.decreaseIndent();
+                    },
+                    getText: function () {
+                        return "";
+                    },
+                    rawWrite: ts.noop,
+                    writeLiteral: function (s) {
+                        return underlying.writeStringLiteral(s);
+                    },
+                    getTextPos: function () {
+                        return 0;
+                    },
+                    getLine: function () {
+                        return 0;
+                    },
+                    getColumn: function () {
+                        return 0;
+                    },
+                    getIndent: function () {
+                        return 0;
+                    },
+                    isAtStartOfLine: function () {
+                        return false;
+                    },
+                    clear: function () {
+                        return underlying.clear();
+                    },
+                    writeKeyword: function (text) {
+                        return underlying.writeKeyword(text);
+                    },
+                    writeOperator: function (text) {
+                        return underlying.writeOperator(text);
+                    },
+                    writePunctuation: function (text) {
+                        return underlying.writePunctuation(text);
+                    },
+                    writeSpace: function (text) {
+                        return underlying.writeSpace(text);
+                    },
+                    writeStringLiteral: function (text) {
+                        return underlying.writeStringLiteral(text);
+                    },
+                    writeParameter: function (text) {
+                        return underlying.writeParameter(text);
+                    },
+                    writeProperty: function (text) {
+                        return underlying.writeProperty(text);
+                    },
+                    writeSymbol: function (text, symbol) {
+                        return underlying.writeSymbol(text, symbol);
+                    },
+                    trackSymbol: function (symbol, enclosing, meaning) {
+                        return underlying.trackSymbol && underlying.trackSymbol(symbol, enclosing, meaning);
+                    },
+                    reportInaccessibleThisError: function () {
+                        return underlying.reportInaccessibleThisError && underlying.reportInaccessibleThisError();
+                    },
+                    reportPrivateInBaseOfClassExpression: function (name) {
+                        return underlying.reportPrivateInBaseOfClassExpression && underlying.reportPrivateInBaseOfClassExpression(name);
+                    },
+                    reportInaccessibleUniqueSymbolError: function () {
+                        return underlying.reportInaccessibleUniqueSymbolError && underlying.reportInaccessibleUniqueSymbolError();
+                    }
+                };
+            }
+        }
+        function getJsxNamespace(location) {
+            if (location) {
+                var file = ts.getSourceFileOfNode(location);
+                if (file) {
+                    if (file.localJsxNamespace) {
+                        return file.localJsxNamespace;
+                    }
+                    var jsxPragma = file.pragmas.get("jsx");
+                    if (jsxPragma) {
+                        var chosenpragma = ts.isArray(jsxPragma) ? jsxPragma[0] : jsxPragma; // TODO: GH#18217
+                        file.localJsxFactory = ts.parseIsolatedEntityName(chosenpragma.arguments.factory, languageVersion);
+                        if (file.localJsxFactory) {
+                            return file.localJsxNamespace = getFirstIdentifier(file.localJsxFactory).escapedText;
+                        }
+                    }
+                }
+            }
+            if (!_jsxNamespace) {
+                _jsxNamespace = "React";
+                if (compilerOptions.jsxFactory) {
+                    _jsxFactoryEntity = ts.parseIsolatedEntityName(compilerOptions.jsxFactory, languageVersion);
+                    if (_jsxFactoryEntity) {
+                        _jsxNamespace = getFirstIdentifier(_jsxFactoryEntity).escapedText;
+                    }
+                }
+                else if (compilerOptions.reactNamespace) {
+                    _jsxNamespace = ts.escapeLeadingUnderscores(compilerOptions.reactNamespace);
+                }
+            }
+            return _jsxNamespace;
+        }
+        function getEmitResolver(sourceFile, cancellationToken) {
+            // Ensure we have all the type information in place for this file so that all the
+            // emitter questions of this resolver will return the right information.
+            getDiagnostics(sourceFile, cancellationToken);
+            return emitResolver;
+        }
+        function error(location, message, arg0, arg1, arg2, arg3) {
+            var diagnostic = location
+                ? ts.createDiagnosticForNode(location, message, arg0, arg1, arg2, arg3)
+                : ts.createCompilerDiagnostic(message, arg0, arg1, arg2, arg3);
+            diagnostics.add(diagnostic);
+        }
+        function addErrorOrSuggestion(isError, diagnostic) {
+            if (isError) {
+                diagnostics.add(diagnostic);
+            }
+            else {
+                suggestionDiagnostics.add(diagnostic.file.fileName, __assign({}, diagnostic, { category: ts.DiagnosticCategory.Suggestion }));
+            }
+        }
+        function errorOrSuggestion(isError, location, message, arg0, arg1, arg2, arg3) {
+            addErrorOrSuggestion(isError, "message" in message ? ts.createDiagnosticForNode(location, message, arg0, arg1, arg2, arg3) : ts.createDiagnosticForNodeFromMessageChain(location, message));
+        }
+        function createSymbol(flags, name, checkFlags) {
+            symbolCount++;
+            var symbol = (new Symbol(flags | 33554432 /* Transient */, name));
+            symbol.checkFlags = checkFlags || 0;
+            return symbol;
+        }
+        function isTransientSymbol(symbol) {
+            return (symbol.flags & 33554432 /* Transient */) !== 0;
+        }
+        function getExcludedSymbolFlags(flags) {
+            var result = 0;
+            if (flags & 2 /* BlockScopedVariable */)
+                result |= 67216319 /* BlockScopedVariableExcludes */;
+            if (flags & 1 /* FunctionScopedVariable */)
+                result |= 67216318 /* FunctionScopedVariableExcludes */;
+            if (flags & 4 /* Property */)
+                result |= 0 /* PropertyExcludes */;
+            if (flags & 8 /* EnumMember */)
+                result |= 68008959 /* EnumMemberExcludes */;
+            if (flags & 16 /* Function */)
+                result |= 67215791 /* FunctionExcludes */;
+            if (flags & 32 /* Class */)
+                result |= 68008383 /* ClassExcludes */;
+            if (flags & 64 /* Interface */)
+                result |= 67901832 /* InterfaceExcludes */;
+            if (flags & 256 /* RegularEnum */)
+                result |= 68008191 /* RegularEnumExcludes */;
+            if (flags & 128 /* ConstEnum */)
+                result |= 68008831 /* ConstEnumExcludes */;
+            if (flags & 512 /* ValueModule */)
+                result |= 67215503 /* ValueModuleExcludes */;
+            if (flags & 8192 /* Method */)
+                result |= 67208127 /* MethodExcludes */;
+            if (flags & 32768 /* GetAccessor */)
+                result |= 67150783 /* GetAccessorExcludes */;
+            if (flags & 65536 /* SetAccessor */)
+                result |= 67183551 /* SetAccessorExcludes */;
+            if (flags & 262144 /* TypeParameter */)
+                result |= 67639784 /* TypeParameterExcludes */;
+            if (flags & 524288 /* TypeAlias */)
+                result |= 67901928 /* TypeAliasExcludes */;
+            if (flags & 2097152 /* Alias */)
+                result |= 2097152 /* AliasExcludes */;
+            return result;
+        }
+        function recordMergedSymbol(target, source) {
+            if (!source.mergeId) {
+                source.mergeId = nextMergeId;
+                nextMergeId++;
+            }
+            mergedSymbols[source.mergeId] = target;
+        }
+        function cloneSymbol(symbol) {
+            var result = createSymbol(symbol.flags, symbol.escapedName);
+            result.declarations = symbol.declarations ? symbol.declarations.slice() : [];
+            result.parent = symbol.parent;
+            if (symbol.valueDeclaration)
+                result.valueDeclaration = symbol.valueDeclaration;
+            if (symbol.constEnumOnlyModule)
+                result.constEnumOnlyModule = true;
+            if (symbol.members)
+                result.members = ts.cloneMap(symbol.members);
+            if (symbol.exports)
+                result.exports = ts.cloneMap(symbol.exports);
+            recordMergedSymbol(result, symbol);
+            return result;
+        }
+        /**
+         * Note: if target is transient, then it is mutable, and mergeSymbol with both mutate and return it.
+         * If target is not transient, mergeSymbol will produce a transient clone, mutate that and return it.
+         */
+        function mergeSymbol(target, source) {
+            if (!(target.flags & getExcludedSymbolFlags(source.flags)) ||
+                (source.flags | target.flags) & 67108864 /* JSContainer */) {
+                ts.Debug.assert(source !== target);
+                if (!(target.flags & 33554432 /* Transient */)) {
+                    target = cloneSymbol(target);
+                }
+                // Javascript static-property-assignment declarations always merge, even though they are also values
+                if (source.flags & 512 /* ValueModule */ && target.flags & 512 /* ValueModule */ && target.constEnumOnlyModule && !source.constEnumOnlyModule) {
+                    // reset flag when merging instantiated module into value module that has only const enums
+                    target.constEnumOnlyModule = false;
+                }
+                target.flags |= source.flags;
+                if (source.valueDeclaration &&
+                    (!target.valueDeclaration ||
+                        ts.isEffectiveModuleDeclaration(target.valueDeclaration) && !ts.isEffectiveModuleDeclaration(source.valueDeclaration))) {
+                    // other kinds of value declarations take precedence over modules
+                    target.valueDeclaration = source.valueDeclaration;
+                }
+                ts.addRange(target.declarations, source.declarations);
+                if (source.members) {
+                    if (!target.members)
+                        target.members = ts.createSymbolTable();
+                    mergeSymbolTable(target.members, source.members);
+                }
+                if (source.exports) {
+                    if (!target.exports)
+                        target.exports = ts.createSymbolTable();
+                    mergeSymbolTable(target.exports, source.exports);
+                }
+                recordMergedSymbol(target, source);
+            }
+            else if (target.flags & 1024 /* NamespaceModule */) {
+                error(ts.getNameOfDeclaration(source.declarations[0]), ts.Diagnostics.Cannot_augment_module_0_with_value_exports_because_it_resolves_to_a_non_module_entity, symbolToString(target));
+            }
+            else {
+                var message_2 = target.flags & 384 /* Enum */ || source.flags & 384 /* Enum */
+                    ? ts.Diagnostics.Enum_declarations_can_only_merge_with_namespace_or_other_enum_declarations
+                    : target.flags & 2 /* BlockScopedVariable */ || source.flags & 2 /* BlockScopedVariable */
+                        ? ts.Diagnostics.Cannot_redeclare_block_scoped_variable_0
+                        : ts.Diagnostics.Duplicate_identifier_0;
+                ts.forEach(source.declarations, function (node) {
+                    var errorNode = (ts.getJavascriptInitializer(node, /*isPrototypeAssignment*/ false) ? ts.getOuterNameOfJsInitializer(node) : ts.getNameOfDeclaration(node)) || node;
+                    error(errorNode, message_2, symbolToString(source));
+                });
+                ts.forEach(target.declarations, function (node) {
+                    var errorNode = (ts.getJavascriptInitializer(node, /*isPrototypeAssignment*/ false) ? ts.getOuterNameOfJsInitializer(node) : ts.getNameOfDeclaration(node)) || node;
+                    error(errorNode, message_2, symbolToString(source));
+                });
+            }
+            return target;
+        }
+        function combineSymbolTables(first, second) {
+            if (!ts.hasEntries(first))
+                return second;
+            if (!ts.hasEntries(second))
+                return first;
+            var combined = ts.createSymbolTable();
+            mergeSymbolTable(combined, first);
+            mergeSymbolTable(combined, second);
+            return combined;
+        }
+        function mergeSymbolTable(target, source) {
+            source.forEach(function (sourceSymbol, id) {
+                target.set(id, target.has(id) ? mergeSymbol(target.get(id), sourceSymbol) : sourceSymbol);
+            });
+        }
+        function mergeModuleAugmentation(moduleName) {
+            var moduleAugmentation = moduleName.parent;
+            if (moduleAugmentation.symbol.declarations[0] !== moduleAugmentation) {
+                // this is a combined symbol for multiple augmentations within the same file.
+                // its symbol already has accumulated information for all declarations
+                // so we need to add it just once - do the work only for first declaration
+                ts.Debug.assert(moduleAugmentation.symbol.declarations.length > 1);
+                return;
+            }
+            if (ts.isGlobalScopeAugmentation(moduleAugmentation)) {
+                mergeSymbolTable(globals, moduleAugmentation.symbol.exports);
+            }
+            else {
+                // find a module that about to be augmented
+                // do not validate names of augmentations that are defined in ambient context
+                var moduleNotFoundError = !(moduleName.parent.parent.flags & 4194304 /* Ambient */)
+                    ? ts.Diagnostics.Invalid_module_name_in_augmentation_module_0_cannot_be_found
+                    : undefined;
+                var mainModule = resolveExternalModuleNameWorker(moduleName, moduleName, moduleNotFoundError, /*isForAugmentation*/ true);
+                if (!mainModule) {
+                    return;
+                }
+                // obtain item referenced by 'export='
+                mainModule = resolveExternalModuleSymbol(mainModule);
+                if (mainModule.flags & 1920 /* Namespace */) {
+                    mainModule = mergeSymbol(mainModule, moduleAugmentation.symbol);
+                }
+                else {
+                    // moduleName will be a StringLiteral since this is not `declare global`.
+                    error(moduleName, ts.Diagnostics.Cannot_augment_module_0_because_it_resolves_to_a_non_module_entity, moduleName.text);
+                }
+            }
+        }
+        function addToSymbolTable(target, source, message) {
+            source.forEach(function (sourceSymbol, id) {
+                var targetSymbol = target.get(id);
+                if (targetSymbol) {
+                    // Error on redeclarations
+                    ts.forEach(targetSymbol.declarations, addDeclarationDiagnostic(ts.unescapeLeadingUnderscores(id), message));
+                }
+                else {
+                    target.set(id, sourceSymbol);
+                }
+            });
+            function addDeclarationDiagnostic(id, message) {
+                return function (declaration) { return diagnostics.add(ts.createDiagnosticForNode(declaration, message, id)); };
+            }
+        }
+        function getSymbolLinks(symbol) {
+            if (symbol.flags & 33554432 /* Transient */)
+                return symbol;
+            var id = getSymbolId(symbol);
+            return symbolLinks[id] || (symbolLinks[id] = {});
+        }
+        function getNodeLinks(node) {
+            var nodeId = getNodeId(node);
+            return nodeLinks[nodeId] || (nodeLinks[nodeId] = { flags: 0 });
+        }
+        function isGlobalSourceFile(node) {
+            return node.kind === 274 /* SourceFile */ && !ts.isExternalOrCommonJsModule(node);
+        }
+        function getSymbol(symbols, name, meaning) {
+            if (meaning) {
+                var symbol = symbols.get(name);
+                if (symbol) {
+                    ts.Debug.assert((ts.getCheckFlags(symbol) & 1 /* Instantiated */) === 0, "Should never get an instantiated symbol here.");
+                    if (symbol.flags & meaning) {
+                        return symbol;
+                    }
+                    if (symbol.flags & 2097152 /* Alias */) {
+                        var target = resolveAlias(symbol);
+                        // Unknown symbol means an error occurred in alias resolution, treat it as positive answer to avoid cascading errors
+                        if (target === unknownSymbol || target.flags & meaning) {
+                            return symbol;
+                        }
+                    }
+                }
+            }
+            // return undefined if we can't find a symbol.
+        }
+        /**
+         * Get symbols that represent parameter-property-declaration as parameter and as property declaration
+         * @param parameter a parameterDeclaration node
+         * @param parameterName a name of the parameter to get the symbols for.
+         * @return a tuple of two symbols
+         */
+        function getSymbolsOfParameterPropertyDeclaration(parameter, parameterName) {
+            var constructorDeclaration = parameter.parent;
+            var classDeclaration = parameter.parent.parent;
+            var parameterSymbol = getSymbol(constructorDeclaration.locals, parameterName, 67216319 /* Value */);
+            var propertySymbol = getSymbol(getMembersOfSymbol(classDeclaration.symbol), parameterName, 67216319 /* Value */);
+            if (parameterSymbol && propertySymbol) {
+                return [parameterSymbol, propertySymbol];
+            }
+            return ts.Debug.fail("There should exist two symbols, one as property declaration and one as parameter declaration");
+        }
+        function isBlockScopedNameDeclaredBeforeUse(declaration, usage) {
+            var declarationFile = ts.getSourceFileOfNode(declaration);
+            var useFile = ts.getSourceFileOfNode(usage);
+            if (declarationFile !== useFile) {
+                if ((moduleKind && (declarationFile.externalModuleIndicator || useFile.externalModuleIndicator)) ||
+                    (!compilerOptions.outFile && !compilerOptions.out) ||
+                    isInTypeQuery(usage) ||
+                    declaration.flags & 4194304 /* Ambient */) {
+                    // nodes are in different files and order cannot be determined
+                    return true;
+                }
+                // declaration is after usage
+                // can be legal if usage is deferred (i.e. inside function or in initializer of instance property)
+                if (isUsedInFunctionOrInstanceProperty(usage, declaration)) {
+                    return true;
+                }
+                var sourceFiles = host.getSourceFiles();
+                return sourceFiles.indexOf(declarationFile) <= sourceFiles.indexOf(useFile);
+            }
+            if (declaration.pos <= usage.pos) {
+                // declaration is before usage
+                if (declaration.kind === 182 /* BindingElement */) {
+                    // still might be illegal if declaration and usage are both binding elements (eg var [a = b, b = b] = [1, 2])
+                    var errorBindingElement = ts.getAncestor(usage, 182 /* BindingElement */);
+                    if (errorBindingElement) {
+                        return ts.findAncestor(errorBindingElement, ts.isBindingElement) !== ts.findAncestor(declaration, ts.isBindingElement) ||
+                            declaration.pos < errorBindingElement.pos;
+                    }
+                    // or it might be illegal if usage happens before parent variable is declared (eg var [a] = a)
+                    return isBlockScopedNameDeclaredBeforeUse(ts.getAncestor(declaration, 232 /* VariableDeclaration */), usage);
+                }
+                else if (declaration.kind === 232 /* VariableDeclaration */) {
+                    // still might be illegal if usage is in the initializer of the variable declaration (eg var a = a)
+                    return !isImmediatelyUsedInInitializerOfBlockScopedVariable(declaration, usage);
+                }
+                else if (ts.isClassDeclaration(declaration)) {
+                    // still might be illegal if the usage is within a computed property name in the class (eg class A { static p = "a"; [A.p]() {} })
+                    return !ts.findAncestor(usage, function (n) { return ts.isComputedPropertyName(n) && n.parent.parent === declaration; });
+                }
+                return true;
+            }
+            // declaration is after usage, but it can still be legal if usage is deferred:
+            // 1. inside an export specifier
+            // 2. inside a function
+            // 3. inside an instance property initializer, a reference to a non-instance property
+            // 4. inside a static property initializer, a reference to a static method in the same class
+            // 5. inside a TS export= declaration (since we will move the export statement during emit to avoid TDZ)
+            // or if usage is in a type context:
+            // 1. inside a type query (typeof in type position)
+            if (usage.parent.kind === 252 /* ExportSpecifier */ || (usage.parent.kind === 249 /* ExportAssignment */ && usage.parent.isExportEquals)) {
+                // export specifiers do not use the variable, they only make it available for use
+                return true;
+            }
+            // When resolving symbols for exports, the `usage` location passed in can be the export site directly
+            if (usage.kind === 249 /* ExportAssignment */ && usage.isExportEquals) {
+                return true;
+            }
+            var container = ts.getEnclosingBlockScopeContainer(declaration);
+            return isInTypeQuery(usage) || isUsedInFunctionOrInstanceProperty(usage, declaration, container);
+            function isImmediatelyUsedInInitializerOfBlockScopedVariable(declaration, usage) {
+                var container = ts.getEnclosingBlockScopeContainer(declaration);
+                switch (declaration.parent.parent.kind) {
+                    case 214 /* VariableStatement */:
+                    case 220 /* ForStatement */:
+                    case 222 /* ForOfStatement */:
+                        // variable statement/for/for-of statement case,
+                        // use site should not be inside variable declaration (initializer of declaration or binding element)
+                        if (isSameScopeDescendentOf(usage, declaration, container)) {
+                            return true;
+                        }
+                        break;
+                }
+                // ForIn/ForOf case - use site should not be used in expression part
+                var grandparent = declaration.parent.parent;
+                return ts.isForInOrOfStatement(grandparent) && isSameScopeDescendentOf(usage, grandparent.expression, container);
+            }
+            function isUsedInFunctionOrInstanceProperty(usage, declaration, container) {
+                return !!ts.findAncestor(usage, function (current) {
+                    if (current === container) {
+                        return "quit";
+                    }
+                    if (ts.isFunctionLike(current)) {
+                        return true;
+                    }
+                    var initializerOfProperty = current.parent &&
+                        current.parent.kind === 152 /* PropertyDeclaration */ &&
+                        current.parent.initializer === current;
+                    if (initializerOfProperty) {
+                        if (ts.hasModifier(current.parent, 32 /* Static */)) {
+                            if (declaration.kind === 154 /* MethodDeclaration */) {
+                                return true;
+                            }
+                        }
+                        else {
+                            var isDeclarationInstanceProperty = declaration.kind === 152 /* PropertyDeclaration */ && !ts.hasModifier(declaration, 32 /* Static */);
+                            if (!isDeclarationInstanceProperty || ts.getContainingClass(usage) !== ts.getContainingClass(declaration)) {
+                                return true;
+                            }
+                        }
+                    }
+                    return false;
+                });
+            }
+        }
+        /**
+         * Resolve a given name for a given meaning at a given location. An error is reported if the name was not found and
+         * the nameNotFoundMessage argument is not undefined. Returns the resolved symbol, or undefined if no symbol with
+         * the given name can be found.
+         *
+         * @param isUse If true, this will count towards --noUnusedLocals / --noUnusedParameters.
+         */
+        function resolveName(location, name, meaning, nameNotFoundMessage, nameArg, isUse, excludeGlobals, suggestedNameNotFoundMessage) {
+            if (excludeGlobals === void 0) { excludeGlobals = false; }
+            return resolveNameHelper(location, name, meaning, nameNotFoundMessage, nameArg, isUse, excludeGlobals, getSymbol, suggestedNameNotFoundMessage);
+        }
+        function resolveNameHelper(location, name, meaning, nameNotFoundMessage, nameArg, isUse, excludeGlobals, lookup, suggestedNameNotFoundMessage) {
+            var originalLocation = location; // needed for did-you-mean error reporting, which gathers candidates starting from the original location
+            var result;
+            var lastLocation;
+            var lastSelfReferenceLocation;
+            var propertyWithInvalidInitializer;
+            var errorLocation = location;
+            var grandparent;
+            var isInExternalModule = false;
+            loop: while (location) {
+                // Locals of a source file are not in scope (because they get merged into the global symbol table)
+                if (location.locals && !isGlobalSourceFile(location)) {
+                    if (result = lookup(location.locals, name, meaning)) {
+                        var useResult = true;
+                        if (ts.isFunctionLike(location) && lastLocation && lastLocation !== location.body) {
+                            // symbol lookup restrictions for function-like declarations
+                            // - Type parameters of a function are in scope in the entire function declaration, including the parameter
+                            //   list and return type. However, local types are only in scope in the function body.
+                            // - parameters are only in the scope of function body
+                            // This restriction does not apply to JSDoc comment types because they are parented
+                            // at a higher level than type parameters would normally be
+                            if (meaning & result.flags & 67901928 /* Type */ && lastLocation.kind !== 286 /* JSDocComment */) {
+                                useResult = result.flags & 262144 /* TypeParameter */
+                                    // type parameters are visible in parameter list, return type and type parameter list
+                                    ? lastLocation === location.type ||
+                                        lastLocation.kind === 149 /* Parameter */ ||
+                                        lastLocation.kind === 148 /* TypeParameter */
+                                    // local types not visible outside the function body
+                                    : false;
+                            }
+                            if (meaning & 67216319 /* Value */ && result.flags & 1 /* FunctionScopedVariable */) {
+                                // parameters are visible only inside function body, parameter list and return type
+                                // technically for parameter list case here we might mix parameters and variables declared in function,
+                                // however it is detected separately when checking initializers of parameters
+                                // to make sure that they reference no variables declared after them.
+                                useResult =
+                                    lastLocation.kind === 149 /* Parameter */ ||
+                                        (lastLocation === location.type &&
+                                            !!ts.findAncestor(result.valueDeclaration, ts.isParameter));
+                            }
+                        }
+                        else if (location.kind === 171 /* ConditionalType */) {
+                            // A type parameter declared using 'infer T' in a conditional type is visible only in
+                            // the true branch of the conditional type.
+                            useResult = lastLocation === location.trueType;
+                        }
+                        if (useResult) {
+                            break loop;
+                        }
+                        else {
+                            result = undefined;
+                        }
+                    }
+                }
+                switch (location.kind) {
+                    case 274 /* SourceFile */:
+                        if (!ts.isExternalOrCommonJsModule(location))
+                            break;
+                        isInExternalModule = true;
+                    // falls through
+                    case 239 /* ModuleDeclaration */:
+                        var moduleExports = getSymbolOfNode(location).exports;
+                        if (location.kind === 274 /* SourceFile */ || ts.isAmbientModule(location)) {
+                            // It's an external module. First see if the module has an export default and if the local
+                            // name of that export default matches.
+                            if (result = moduleExports.get("default" /* Default */)) {
+                                var localSymbol = ts.getLocalSymbolForExportDefault(result);
+                                if (localSymbol && (result.flags & meaning) && localSymbol.escapedName === name) {
+                                    break loop;
+                                }
+                                result = undefined;
+                            }
+                            // Because of module/namespace merging, a module's exports are in scope,
+                            // yet we never want to treat an export specifier as putting a member in scope.
+                            // Therefore, if the name we find is purely an export specifier, it is not actually considered in scope.
+                            // Two things to note about this:
+                            //     1. We have to check this without calling getSymbol. The problem with calling getSymbol
+                            //        on an export specifier is that it might find the export specifier itself, and try to
+                            //        resolve it as an alias. This will cause the checker to consider the export specifier
+                            //        a circular alias reference when it might not be.
+                            //     2. We check === SymbolFlags.Alias in order to check that the symbol is *purely*
+                            //        an alias. If we used &, we'd be throwing out symbols that have non alias aspects,
+                            //        which is not the desired behavior.
+                            var moduleExport = moduleExports.get(name);
+                            if (moduleExport &&
+                                moduleExport.flags === 2097152 /* Alias */ &&
+                                ts.getDeclarationOfKind(moduleExport, 252 /* ExportSpecifier */)) {
+                                break;
+                            }
+                        }
+                        // ES6 exports are also visible locally (except for 'default'), but commonjs exports are not (except typedefs)
+                        if (name !== "default" /* Default */ && (result = lookup(moduleExports, name, meaning & 2623475 /* ModuleMember */))) {
+                            if (ts.isSourceFile(location) && location.commonJsModuleIndicator && !result.declarations.some(ts.isJSDocTypeAlias)) {
+                                result = undefined;
+                            }
+                            else {
+                                break loop;
+                            }
+                        }
+                        break;
+                    case 238 /* EnumDeclaration */:
+                        if (result = lookup(getSymbolOfNode(location).exports, name, meaning & 8 /* EnumMember */)) {
+                            break loop;
+                        }
+                        break;
+                    case 152 /* PropertyDeclaration */:
+                    case 151 /* PropertySignature */:
+                        // TypeScript 1.0 spec (April 2014): 8.4.1
+                        // Initializer expressions for instance member variables are evaluated in the scope
+                        // of the class constructor body but are not permitted to reference parameters or
+                        // local variables of the constructor. This effectively means that entities from outer scopes
+                        // by the same name as a constructor parameter or local variable are inaccessible
+                        // in initializer expressions for instance member variables.
+                        if (ts.isClassLike(location.parent) && !ts.hasModifier(location, 32 /* Static */)) {
+                            var ctor = findConstructorDeclaration(location.parent);
+                            if (ctor && ctor.locals) {
+                                if (lookup(ctor.locals, name, meaning & 67216319 /* Value */)) {
+                                    // Remember the property node, it will be used later to report appropriate error
+                                    propertyWithInvalidInitializer = location;
+                                }
+                            }
+                        }
+                        break;
+                    case 235 /* ClassDeclaration */:
+                    case 205 /* ClassExpression */:
+                    case 236 /* InterfaceDeclaration */:
+                        if (result = lookup(getMembersOfSymbol(getSymbolOfNode(location)), name, meaning & 67901928 /* Type */)) {
+                            if (!isTypeParameterSymbolDeclaredInContainer(result, location)) {
+                                // ignore type parameters not declared in this container
+                                result = undefined;
+                                break;
+                            }
+                            if (lastLocation && ts.hasModifier(lastLocation, 32 /* Static */)) {
+                                // TypeScript 1.0 spec (April 2014): 3.4.1
+                                // The scope of a type parameter extends over the entire declaration with which the type
+                                // parameter list is associated, with the exception of static member declarations in classes.
+                                error(errorLocation, ts.Diagnostics.Static_members_cannot_reference_class_type_parameters);
+                                return undefined;
+                            }
+                            break loop;
+                        }
+                        if (location.kind === 205 /* ClassExpression */ && meaning & 32 /* Class */) {
+                            var className = location.name;
+                            if (className && name === className.escapedText) {
+                                result = location.symbol;
+                                break loop;
+                            }
+                        }
+                        break;
+                    case 207 /* ExpressionWithTypeArguments */:
+                        // The type parameters of a class are not in scope in the base class expression.
+                        if (lastLocation === location.expression && location.parent.token === 85 /* ExtendsKeyword */) {
+                            var container = location.parent.parent;
+                            if (ts.isClassLike(container) && (result = lookup(getSymbolOfNode(container).members, name, meaning & 67901928 /* Type */))) {
+                                if (nameNotFoundMessage) {
+                                    error(errorLocation, ts.Diagnostics.Base_class_expressions_cannot_reference_class_type_parameters);
+                                }
+                                return undefined;
+                            }
+                        }
+                        break;
+                    // It is not legal to reference a class's own type parameters from a computed property name that
+                    // belongs to the class. For example:
+                    //
+                    //   function foo<T>() { return '' }
+                    //   class C<T> { // <-- Class's own type parameter T
+                    //       [foo<T>()]() { } // <-- Reference to T from class's own computed property
+                    //   }
+                    //
+                    case 147 /* ComputedPropertyName */:
+                        grandparent = location.parent.parent;
+                        if (ts.isClassLike(grandparent) || grandparent.kind === 236 /* InterfaceDeclaration */) {
+                            // A reference to this grandparent's type parameters would be an error
+                            if (result = lookup(getSymbolOfNode(grandparent).members, name, meaning & 67901928 /* Type */)) {
+                                error(errorLocation, ts.Diagnostics.A_computed_property_name_cannot_reference_a_type_parameter_from_its_containing_type);
+                                return undefined;
+                            }
+                        }
+                        break;
+                    case 154 /* MethodDeclaration */:
+                    case 153 /* MethodSignature */:
+                    case 155 /* Constructor */:
+                    case 156 /* GetAccessor */:
+                    case 157 /* SetAccessor */:
+                    case 234 /* FunctionDeclaration */:
+                    case 193 /* ArrowFunction */:
+                        if (meaning & 3 /* Variable */ && name === "arguments") {
+                            result = argumentsSymbol;
+                            break loop;
+                        }
+                        break;
+                    case 192 /* FunctionExpression */:
+                        if (meaning & 3 /* Variable */ && name === "arguments") {
+                            result = argumentsSymbol;
+                            break loop;
+                        }
+                        if (meaning & 16 /* Function */) {
+                            var functionName = location.name;
+                            if (functionName && name === functionName.escapedText) {
+                                result = location.symbol;
+                                break loop;
+                            }
+                        }
+                        break;
+                    case 150 /* Decorator */:
+                        // Decorators are resolved at the class declaration. Resolving at the parameter
+                        // or member would result in looking up locals in the method.
+                        //
+                        //   function y() {}
+                        //   class C {
+                        //       method(@y x, y) {} // <-- decorator y should be resolved at the class declaration, not the parameter.
+                        //   }
+                        //
+                        if (location.parent && location.parent.kind === 149 /* Parameter */) {
+                            location = location.parent;
+                        }
+                        //
+                        //   function y() {}
+                        //   class C {
+                        //       @y method(x, y) {} // <-- decorator y should be resolved at the class declaration, not the method.
+                        //   }
+                        //
+                        if (location.parent && ts.isClassElement(location.parent)) {
+                            location = location.parent;
+                        }
+                        break;
+                    case 297 /* JSDocTypedefTag */:
+                    case 292 /* JSDocCallbackTag */:
+                        // js type aliases do not resolve names from their host, so skip past it
+                        location = ts.getJSDocHost(location);
+                        break;
+                }
+                if (isSelfReferenceLocation(location)) {
+                    lastSelfReferenceLocation = location;
+                }
+                lastLocation = location;
+                location = location.parent;
+            }
+            // We just climbed up parents looking for the name, meaning that we started in a descendant node of `lastLocation`.
+            // If `result === lastSelfReferenceLocation.symbol`, that means that we are somewhere inside `lastSelfReferenceLocation` looking up a name, and resolving to `lastLocation` itself.
+            // That means that this is a self-reference of `lastLocation`, and shouldn't count this when considering whether `lastLocation` is used.
+            if (isUse && result && (!lastSelfReferenceLocation || result !== lastSelfReferenceLocation.symbol)) {
+                result.isReferenced |= meaning;
+            }
+            if (!result) {
+                if (lastLocation) {
+                    ts.Debug.assert(lastLocation.kind === 274 /* SourceFile */);
+                    if (lastLocation.commonJsModuleIndicator && name === "exports") {
+                        return lastLocation.symbol;
+                    }
+                }
+                if (!excludeGlobals) {
+                    result = lookup(globals, name, meaning);
+                }
+            }
+            if (!result) {
+                if (originalLocation && ts.isInJavaScriptFile(originalLocation) && originalLocation.parent) {
+                    if (ts.isRequireCall(originalLocation.parent, /*checkArgumentIsStringLiteralLike*/ false)) {
+                        return requireSymbol;
+                    }
+                    if (ts.isIdentifier(originalLocation) && ts.isPropertyAccessExpression(originalLocation.parent) &&
+                        originalLocation.escapedText === "module" && originalLocation.parent.name.escapedText === "exports") {
+                        return moduleSymbol;
+                    }
+                }
+            }
+            if (!result) {
+                if (nameNotFoundMessage) {
+                    if (!errorLocation ||
+                        !checkAndReportErrorForMissingPrefix(errorLocation, name, nameArg) && // TODO: GH#18217
+                            !checkAndReportErrorForExtendingInterface(errorLocation) &&
+                            !checkAndReportErrorForUsingTypeAsNamespace(errorLocation, name, meaning) &&
+                            !checkAndReportErrorForUsingTypeAsValue(errorLocation, name, meaning) &&
+                            !checkAndReportErrorForUsingNamespaceModuleAsValue(errorLocation, name, meaning)) {
+                        var suggestion = void 0;
+                        if (suggestedNameNotFoundMessage && suggestionCount < maximumSuggestionCount) {
+                            suggestion = getSuggestionForNonexistentSymbol(originalLocation, name, meaning);
+                            if (suggestion) {
+                                error(errorLocation, suggestedNameNotFoundMessage, diagnosticName(nameArg), suggestion);
+                            }
+                        }
+                        if (!suggestion) {
+                            error(errorLocation, nameNotFoundMessage, diagnosticName(nameArg));
+                        }
+                        suggestionCount++;
+                    }
+                }
+                return undefined;
+            }
+            // Perform extra checks only if error reporting was requested
+            if (nameNotFoundMessage) {
+                if (propertyWithInvalidInitializer) {
+                    // We have a match, but the reference occurred within a property initializer and the identifier also binds
+                    // to a local variable in the constructor where the code will be emitted.
+                    var propertyName = propertyWithInvalidInitializer.name;
+                    error(errorLocation, ts.Diagnostics.Initializer_of_instance_member_variable_0_cannot_reference_identifier_1_declared_in_the_constructor, ts.declarationNameToString(propertyName), diagnosticName(nameArg));
+                    return undefined;
+                }
+                // Only check for block-scoped variable if we have an error location and are looking for the
+                // name with variable meaning
+                //      For example,
+                //          declare module foo {
+                //              interface bar {}
+                //          }
+                //      const foo/*1*/: foo/*2*/.bar;
+                // The foo at /*1*/ and /*2*/ will share same symbol with two meanings:
+                // block-scoped variable and namespace module. However, only when we
+                // try to resolve name in /*1*/ which is used in variable position,
+                // we want to check for block-scoped
+                if (errorLocation &&
+                    (meaning & 2 /* BlockScopedVariable */ ||
+                        ((meaning & 32 /* Class */ || meaning & 384 /* Enum */) && (meaning & 67216319 /* Value */) === 67216319 /* Value */))) {
+                    var exportOrLocalSymbol = getExportSymbolOfValueSymbolIfExported(result);
+                    if (exportOrLocalSymbol.flags & 2 /* BlockScopedVariable */ || exportOrLocalSymbol.flags & 32 /* Class */ || exportOrLocalSymbol.flags & 384 /* Enum */) {
+                        checkResolvedBlockScopedVariable(exportOrLocalSymbol, errorLocation);
+                    }
+                }
+                // If we're in an external module, we can't reference value symbols created from UMD export declarations
+                if (result && isInExternalModule && (meaning & 67216319 /* Value */) === 67216319 /* Value */ && !(originalLocation.flags & 2097152 /* JSDoc */)) {
+                    var decls = result.declarations;
+                    if (decls && decls.length === 1 && decls[0].kind === 242 /* NamespaceExportDeclaration */) {
+                        error(errorLocation, ts.Diagnostics._0_refers_to_a_UMD_global_but_the_current_file_is_a_module_Consider_adding_an_import_instead, ts.unescapeLeadingUnderscores(name)); // TODO: GH#18217
+                    }
+                }
+            }
+            return result;
+        }
+        function isSelfReferenceLocation(node) {
+            switch (node.kind) {
+                case 234 /* FunctionDeclaration */:
+                case 235 /* ClassDeclaration */:
+                case 236 /* InterfaceDeclaration */:
+                case 238 /* EnumDeclaration */:
+                case 237 /* TypeAliasDeclaration */:
+                case 239 /* ModuleDeclaration */: // For `namespace N { N; }`
+                    return true;
+                default:
+                    return false;
+            }
+        }
+        function diagnosticName(nameArg) {
+            return ts.isString(nameArg) ? ts.unescapeLeadingUnderscores(nameArg) : ts.declarationNameToString(nameArg);
+        }
+        function isTypeParameterSymbolDeclaredInContainer(symbol, container) {
+            for (var _i = 0, _a = symbol.declarations; _i < _a.length; _i++) {
+                var decl = _a[_i];
+                if (decl.kind === 148 /* TypeParameter */) {
+                    var parent = ts.isJSDocTemplateTag(decl.parent) ? ts.getJSDocHost(decl.parent) : decl.parent;
+                    if (parent === container) {
+                        return !(ts.isJSDocTemplateTag(decl.parent) && ts.find(decl.parent.parent.tags, ts.isJSDocTypeAlias)); // TODO: GH#18217
+                    }
+                }
+            }
+            return false;
+        }
+        function checkAndReportErrorForMissingPrefix(errorLocation, name, nameArg) {
+            if (!ts.isIdentifier(errorLocation) || errorLocation.escapedText !== name || isTypeReferenceIdentifier(errorLocation) || isInTypeQuery(errorLocation)) {
+                return false;
+            }
+            var container = ts.getThisContainer(errorLocation, /*includeArrowFunctions*/ false);
+            var location = container;
+            while (location) {
+                if (ts.isClassLike(location.parent)) {
+                    var classSymbol = getSymbolOfNode(location.parent);
+                    if (!classSymbol) {
+                        break;
+                    }
+                    // Check to see if a static member exists.
+                    var constructorType = getTypeOfSymbol(classSymbol);
+                    if (getPropertyOfType(constructorType, name)) {
+                        error(errorLocation, ts.Diagnostics.Cannot_find_name_0_Did_you_mean_the_static_member_1_0, diagnosticName(nameArg), symbolToString(classSymbol));
+                        return true;
+                    }
+                    // No static member is present.
+                    // Check if we're in an instance method and look for a relevant instance member.
+                    if (location === container && !ts.hasModifier(location, 32 /* Static */)) {
+                        var instanceType = getDeclaredTypeOfSymbol(classSymbol).thisType; // TODO: GH#18217
+                        if (getPropertyOfType(instanceType, name)) {
+                            error(errorLocation, ts.Diagnostics.Cannot_find_name_0_Did_you_mean_the_instance_member_this_0, diagnosticName(nameArg));
+                            return true;
+                        }
+                    }
+                }
+                location = location.parent;
+            }
+            return false;
+        }
+        function checkAndReportErrorForExtendingInterface(errorLocation) {
+            var expression = getEntityNameForExtendingInterface(errorLocation);
+            if (expression && resolveEntityName(expression, 64 /* Interface */, /*ignoreErrors*/ true)) {
+                error(errorLocation, ts.Diagnostics.Cannot_extend_an_interface_0_Did_you_mean_implements, ts.getTextOfNode(expression));
+                return true;
+            }
+            return false;
+        }
+        /**
+         * Climbs up parents to an ExpressionWithTypeArguments, and returns its expression,
+         * but returns undefined if that expression is not an EntityNameExpression.
+         */
+        function getEntityNameForExtendingInterface(node) {
+            switch (node.kind) {
+                case 71 /* Identifier */:
+                case 185 /* PropertyAccessExpression */:
+                    return node.parent ? getEntityNameForExtendingInterface(node.parent) : undefined;
+                case 207 /* ExpressionWithTypeArguments */:
+                    if (ts.isEntityNameExpression(node.expression)) {
+                        return node.expression;
+                    }
+                // falls through
+                default:
+                    return undefined;
+            }
+        }
+        function checkAndReportErrorForUsingTypeAsNamespace(errorLocation, name, meaning) {
+            var namespaceMeaning = 1920 /* Namespace */ | (ts.isInJavaScriptFile(errorLocation) ? 67216319 /* Value */ : 0);
+            if (meaning === namespaceMeaning) {
+                var symbol = resolveSymbol(resolveName(errorLocation, name, 67901928 /* Type */ & ~namespaceMeaning, /*nameNotFoundMessage*/ undefined, /*nameArg*/ undefined, /*isUse*/ false));
+                var parent = errorLocation.parent;
+                if (symbol) {
+                    if (ts.isQualifiedName(parent)) {
+                        ts.Debug.assert(parent.left === errorLocation, "Should only be resolving left side of qualified name as a namespace");
+                        var propName = parent.right.escapedText;
+                        var propType = getPropertyOfType(getDeclaredTypeOfSymbol(symbol), propName);
+                        if (propType) {
+                            error(parent, ts.Diagnostics.Cannot_access_0_1_because_0_is_a_type_but_not_a_namespace_Did_you_mean_to_retrieve_the_type_of_the_property_1_in_0_with_0_1, ts.unescapeLeadingUnderscores(name), ts.unescapeLeadingUnderscores(propName));
+                            return true;
+                        }
+                    }
+                    error(errorLocation, ts.Diagnostics._0_only_refers_to_a_type_but_is_being_used_as_a_namespace_here, ts.unescapeLeadingUnderscores(name));
+                    return true;
+                }
+            }
+            return false;
+        }
+        function checkAndReportErrorForUsingTypeAsValue(errorLocation, name, meaning) {
+            if (meaning & (67216319 /* Value */ & ~1024 /* NamespaceModule */)) {
+                if (name === "any" || name === "string" || name === "number" || name === "boolean" || name === "never") {
+                    error(errorLocation, ts.Diagnostics._0_only_refers_to_a_type_but_is_being_used_as_a_value_here, ts.unescapeLeadingUnderscores(name));
+                    return true;
+                }
+                var symbol = resolveSymbol(resolveName(errorLocation, name, 67901928 /* Type */ & ~67216319 /* Value */, /*nameNotFoundMessage*/ undefined, /*nameArg*/ undefined, /*isUse*/ false));
+                if (symbol && !(symbol.flags & 1024 /* NamespaceModule */)) {
+                    error(errorLocation, ts.Diagnostics._0_only_refers_to_a_type_but_is_being_used_as_a_value_here, ts.unescapeLeadingUnderscores(name));
+                    return true;
+                }
+            }
+            return false;
+        }
+        function checkAndReportErrorForUsingNamespaceModuleAsValue(errorLocation, name, meaning) {
+            if (meaning & (67216319 /* Value */ & ~1024 /* NamespaceModule */ & ~67901928 /* Type */)) {
+                var symbol = resolveSymbol(resolveName(errorLocation, name, 1024 /* NamespaceModule */ & ~67216319 /* Value */, /*nameNotFoundMessage*/ undefined, /*nameArg*/ undefined, /*isUse*/ false));
+                if (symbol) {
+                    error(errorLocation, ts.Diagnostics.Cannot_use_namespace_0_as_a_value, ts.unescapeLeadingUnderscores(name));
+                    return true;
+                }
+            }
+            else if (meaning & (67901928 /* Type */ & ~1024 /* NamespaceModule */ & ~67216319 /* Value */)) {
+                var symbol = resolveSymbol(resolveName(errorLocation, name, (512 /* ValueModule */ | 1024 /* NamespaceModule */) & ~67901928 /* Type */, /*nameNotFoundMessage*/ undefined, /*nameArg*/ undefined, /*isUse*/ false));
+                if (symbol) {
+                    error(errorLocation, ts.Diagnostics.Cannot_use_namespace_0_as_a_type, ts.unescapeLeadingUnderscores(name));
+                    return true;
+                }
+            }
+            return false;
+        }
+        function checkResolvedBlockScopedVariable(result, errorLocation) {
+            ts.Debug.assert(!!(result.flags & 2 /* BlockScopedVariable */ || result.flags & 32 /* Class */ || result.flags & 384 /* Enum */));
+            // Block-scoped variables cannot be used before their definition
+            var declaration = ts.forEach(result.declarations, function (d) { return ts.isBlockOrCatchScoped(d) || ts.isClassLike(d) || (d.kind === 238 /* EnumDeclaration */) ? d : undefined; });
+            if (declaration === undefined)
+                return ts.Debug.fail("Declaration to checkResolvedBlockScopedVariable is undefined");
+            if (!(declaration.flags & 4194304 /* Ambient */) && !isBlockScopedNameDeclaredBeforeUse(declaration, errorLocation)) {
+                if (result.flags & 2 /* BlockScopedVariable */) {
+                    error(errorLocation, ts.Diagnostics.Block_scoped_variable_0_used_before_its_declaration, ts.declarationNameToString(ts.getNameOfDeclaration(declaration)));
+                }
+                else if (result.flags & 32 /* Class */) {
+                    error(errorLocation, ts.Diagnostics.Class_0_used_before_its_declaration, ts.declarationNameToString(ts.getNameOfDeclaration(declaration)));
+                }
+                else if (result.flags & 256 /* RegularEnum */) {
+                    error(errorLocation, ts.Diagnostics.Enum_0_used_before_its_declaration, ts.declarationNameToString(ts.getNameOfDeclaration(declaration)));
+                }
+            }
+        }
+        /* Starting from 'initial' node walk up the parent chain until 'stopAt' node is reached.
+         * If at any point current node is equal to 'parent' node - return true.
+         * Return false if 'stopAt' node is reached or isFunctionLike(current) === true.
+         */
+        function isSameScopeDescendentOf(initial, parent, stopAt) {
+            return !!parent && !!ts.findAncestor(initial, function (n) { return n === stopAt || ts.isFunctionLike(n) ? "quit" : n === parent; });
+        }
+        function getAnyImportSyntax(node) {
+            switch (node.kind) {
+                case 243 /* ImportEqualsDeclaration */:
+                    return node;
+                case 245 /* ImportClause */:
+                    return node.parent;
+                case 246 /* NamespaceImport */:
+                    return node.parent.parent;
+                case 248 /* ImportSpecifier */:
+                    return node.parent.parent.parent;
+                default:
+                    return undefined;
+            }
+        }
+        function getDeclarationOfAliasSymbol(symbol) {
+            return ts.find(symbol.declarations, ts.isAliasSymbolDeclaration);
+        }
+        function getTargetOfImportEqualsDeclaration(node, dontResolveAlias) {
+            if (node.moduleReference.kind === 254 /* ExternalModuleReference */) {
+                return resolveExternalModuleSymbol(resolveExternalModuleName(node, ts.getExternalModuleImportEqualsDeclarationExpression(node)));
+            }
+            return getSymbolOfPartOfRightHandSideOfImportEquals(node.moduleReference, dontResolveAlias);
+        }
+        function resolveExportByName(moduleSymbol, name, dontResolveAlias) {
+            var exportValue = moduleSymbol.exports.get("export=" /* ExportEquals */);
+            return exportValue
+                ? getPropertyOfType(getTypeOfSymbol(exportValue), name)
+                : resolveSymbol(moduleSymbol.exports.get(name), dontResolveAlias);
+        }
+        function isSyntacticDefault(node) {
+            return ((ts.isExportAssignment(node) && !node.isExportEquals) || ts.hasModifier(node, 512 /* Default */) || ts.isExportSpecifier(node));
+        }
+        function canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias) {
+            if (!allowSyntheticDefaultImports) {
+                return false;
+            }
+            // Declaration files (and ambient modules)
+            if (!file || file.isDeclarationFile) {
+                // Definitely cannot have a synthetic default if they have a syntactic default member specified
+                var defaultExportSymbol = resolveExportByName(moduleSymbol, "default" /* Default */, /*dontResolveAlias*/ true); // Dont resolve alias because we want the immediately exported symbol's declaration
+                if (defaultExportSymbol && ts.some(defaultExportSymbol.declarations, isSyntacticDefault)) {
+                    return false;
+                }
+                // It _might_ still be incorrect to assume there is no __esModule marker on the import at runtime, even if there is no `default` member
+                // So we check a bit more,
+                if (resolveExportByName(moduleSymbol, ts.escapeLeadingUnderscores("__esModule"), dontResolveAlias)) {
+                    // If there is an `__esModule` specified in the declaration (meaning someone explicitly added it or wrote it in their code),
+                    // it definitely is a module and does not have a synthetic default
+                    return false;
+                }
+                // There are _many_ declaration files not written with esmodules in mind that still get compiled into a format with __esModule set
+                // Meaning there may be no default at runtime - however to be on the permissive side, we allow access to a synthetic default member
+                // as there is no marker to indicate if the accompanying JS has `__esModule` or not, or is even native esm
+                return true;
+            }
+            // TypeScript files never have a synthetic default (as they are always emitted with an __esModule marker) _unless_ they contain an export= statement
+            if (!ts.isSourceFileJavaScript(file)) {
+                return hasExportAssignmentSymbol(moduleSymbol);
+            }
+            // JS files have a synthetic default if they do not contain ES2015+ module syntax (export = is not valid in js) _and_ do not have an __esModule marker
+            return !file.externalModuleIndicator && !resolveExportByName(moduleSymbol, ts.escapeLeadingUnderscores("__esModule"), dontResolveAlias);
+        }
+        function getTargetOfImportClause(node, dontResolveAlias) {
+            var moduleSymbol = resolveExternalModuleName(node, node.parent.moduleSpecifier);
+            if (moduleSymbol) {
+                var exportDefaultSymbol = void 0;
+                if (ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
+                    exportDefaultSymbol = moduleSymbol;
+                }
+                else {
+                    exportDefaultSymbol = resolveExportByName(moduleSymbol, "default" /* Default */, dontResolveAlias);
+                }
+                var file = ts.find(moduleSymbol.declarations, ts.isSourceFile);
+                var hasSyntheticDefault = canHaveSyntheticDefault(file, moduleSymbol, dontResolveAlias);
+                if (!exportDefaultSymbol && !hasSyntheticDefault) {
+                    error(node.name, ts.Diagnostics.Module_0_has_no_default_export, symbolToString(moduleSymbol));
+                }
+                else if (hasSyntheticDefault) {
+                    // per emit behavior, a synthetic default overrides a "real" .default member if `__esModule` is not present
+                    return resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
+                }
+                return exportDefaultSymbol;
+            }
+        }
+        function getTargetOfNamespaceImport(node, dontResolveAlias) {
+            var moduleSpecifier = node.parent.parent.moduleSpecifier;
+            return resolveESModuleSymbol(resolveExternalModuleName(node, moduleSpecifier), moduleSpecifier, dontResolveAlias);
+        }
+        // This function creates a synthetic symbol that combines the value side of one symbol with the
+        // type/namespace side of another symbol. Consider this example:
+        //
+        //   declare module graphics {
+        //       interface Point {
+        //           x: number;
+        //           y: number;
+        //       }
+        //   }
+        //   declare var graphics: {
+        //       Point: new (x: number, y: number) => graphics.Point;
+        //   }
+        //   declare module "graphics" {
+        //       export = graphics;
+        //   }
+        //
+        // An 'import { Point } from "graphics"' needs to create a symbol that combines the value side 'Point'
+        // property with the type/namespace side interface 'Point'.
+        function combineValueAndTypeSymbols(valueSymbol, typeSymbol) {
+            if (valueSymbol === unknownSymbol && typeSymbol === unknownSymbol) {
+                return unknownSymbol;
+            }
+            if (valueSymbol.flags & (67901928 /* Type */ | 1920 /* Namespace */)) {
+                return valueSymbol;
+            }
+            var result = createSymbol(valueSymbol.flags | typeSymbol.flags, valueSymbol.escapedName);
+            result.declarations = ts.deduplicate(ts.concatenate(valueSymbol.declarations, typeSymbol.declarations), ts.equateValues);
+            result.parent = valueSymbol.parent || typeSymbol.parent;
+            if (valueSymbol.valueDeclaration)
+                result.valueDeclaration = valueSymbol.valueDeclaration;
+            if (typeSymbol.members)
+                result.members = typeSymbol.members;
+            if (valueSymbol.exports)
+                result.exports = valueSymbol.exports;
+            return result;
+        }
+        function getExportOfModule(symbol, name, dontResolveAlias) {
+            if (symbol.flags & 1536 /* Module */) {
+                return resolveSymbol(getExportsOfSymbol(symbol).get(name), dontResolveAlias);
+            }
+        }
+        function getPropertyOfVariable(symbol, name) {
+            if (symbol.flags & 3 /* Variable */) {
+                var typeAnnotation = symbol.valueDeclaration.type;
+                if (typeAnnotation) {
+                    return resolveSymbol(getPropertyOfType(getTypeFromTypeNode(typeAnnotation), name)); // TODO: GH#18217
+                }
+            }
+        }
+        function getExternalModuleMember(node, specifier, dontResolveAlias) {
+            if (dontResolveAlias === void 0) { dontResolveAlias = false; }
+            var moduleSymbol = resolveExternalModuleName(node, node.moduleSpecifier); // TODO: GH#18217
+            var targetSymbol = resolveESModuleSymbol(moduleSymbol, node.moduleSpecifier, dontResolveAlias);
+            if (targetSymbol) {
+                var name = specifier.propertyName || specifier.name;
+                if (name.escapedText) {
+                    if (ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
+                        return moduleSymbol;
+                    }
+                    var symbolFromVariable = void 0;
+                    // First check if module was specified with "export=". If so, get the member from the resolved type
+                    if (moduleSymbol && moduleSymbol.exports && moduleSymbol.exports.get("export=" /* ExportEquals */)) {
+                        symbolFromVariable = getPropertyOfType(getTypeOfSymbol(targetSymbol), name.escapedText);
+                    }
+                    else {
+                        symbolFromVariable = getPropertyOfVariable(targetSymbol, name.escapedText);
+                    }
+                    // if symbolFromVariable is export - get its final target
+                    symbolFromVariable = resolveSymbol(symbolFromVariable, dontResolveAlias);
+                    var symbolFromModule = getExportOfModule(targetSymbol, name.escapedText, dontResolveAlias);
+                    // If the export member we're looking for is default, and there is no real default but allowSyntheticDefaultImports is on, return the entire module as the default
+                    if (!symbolFromModule && allowSyntheticDefaultImports && name.escapedText === "default" /* Default */) {
+                        symbolFromModule = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) || resolveSymbol(moduleSymbol, dontResolveAlias);
+                    }
+                    var symbol = symbolFromModule && symbolFromVariable && symbolFromModule !== symbolFromVariable ?
+                        combineValueAndTypeSymbols(symbolFromVariable, symbolFromModule) :
+                        symbolFromModule || symbolFromVariable;
+                    if (!symbol) {
+                        var moduleName = getFullyQualifiedName(moduleSymbol);
+                        var declarationName = ts.declarationNameToString(name);
+                        var suggestion = getSuggestionForNonexistentModule(name, targetSymbol);
+                        if (suggestion !== undefined) {
+                            error(name, ts.Diagnostics.Module_0_has_no_exported_member_1_Did_you_mean_2, moduleName, declarationName, suggestion);
+                        }
+                        else {
+                            error(name, ts.Diagnostics.Module_0_has_no_exported_member_1, moduleName, declarationName);
+                        }
+                    }
+                    return symbol;
+                }
+            }
+        }
+        function getTargetOfImportSpecifier(node, dontResolveAlias) {
+            return getExternalModuleMember(node.parent.parent.parent, node, dontResolveAlias);
+        }
+        function getTargetOfNamespaceExportDeclaration(node, dontResolveAlias) {
+            return resolveExternalModuleSymbol(node.parent.symbol, dontResolveAlias);
+        }
+        function getTargetOfExportSpecifier(node, meaning, dontResolveAlias) {
+            return node.parent.parent.moduleSpecifier ?
+                getExternalModuleMember(node.parent.parent, node, dontResolveAlias) :
+                resolveEntityName(node.propertyName || node.name, meaning, /*ignoreErrors*/ false, dontResolveAlias);
+        }
+        function getTargetOfExportAssignment(node, dontResolveAlias) {
+            var expression = (ts.isExportAssignment(node) ? node.expression : node.right);
+            if (ts.isClassExpression(expression)) {
+                return checkExpression(expression).symbol;
+            }
+            var aliasLike = resolveEntityName(expression, 67216319 /* Value */ | 67901928 /* Type */ | 1920 /* Namespace */, /*ignoreErrors*/ true, dontResolveAlias);
+            if (aliasLike) {
+                return aliasLike;
+            }
+            checkExpression(expression);
+            return getNodeLinks(expression).resolvedSymbol;
+        }
+        function getTargetOfAliasDeclaration(node, dontRecursivelyResolve) {
+            if (dontRecursivelyResolve === void 0) { dontRecursivelyResolve = false; }
+            switch (node.kind) {
+                case 243 /* ImportEqualsDeclaration */:
+                    return getTargetOfImportEqualsDeclaration(node, dontRecursivelyResolve);
+                case 245 /* ImportClause */:
+                    return getTargetOfImportClause(node, dontRecursivelyResolve);
+                case 246 /* NamespaceImport */:
+                    return getTargetOfNamespaceImport(node, dontRecursivelyResolve);
+                case 248 /* ImportSpecifier */:
+                    return getTargetOfImportSpecifier(node, dontRecursivelyResolve);
+                case 252 /* ExportSpecifier */:
+                    return getTargetOfExportSpecifier(node, 67216319 /* Value */ | 67901928 /* Type */ | 1920 /* Namespace */, dontRecursivelyResolve);
+                case 249 /* ExportAssignment */:
+                case 200 /* BinaryExpression */:
+                    return getTargetOfExportAssignment(node, dontRecursivelyResolve);
+                case 242 /* NamespaceExportDeclaration */:
+                    return getTargetOfNamespaceExportDeclaration(node, dontRecursivelyResolve);
+                default:
+                    return ts.Debug.fail();
+            }
+        }
+        /**
+         * Indicates that a symbol is an alias that does not merge with a local declaration.
+         * OR Is a JSContainer which may merge an alias with a local declaration
+         */
+        function isNonLocalAlias(symbol, excludes) {
+            if (excludes === void 0) { excludes = 67216319 /* Value */ | 67901928 /* Type */ | 1920 /* Namespace */; }
+            if (!symbol)
+                return false;
+            return (symbol.flags & (2097152 /* Alias */ | excludes)) === 2097152 /* Alias */ || !!(symbol.flags & 2097152 /* Alias */ && symbol.flags & 67108864 /* JSContainer */);
+        }
+        function resolveSymbol(symbol, dontResolveAlias) {
+            return !dontResolveAlias && isNonLocalAlias(symbol) ? resolveAlias(symbol) : symbol;
+        }
+        function resolveAlias(symbol) {
+            ts.Debug.assert((symbol.flags & 2097152 /* Alias */) !== 0, "Should only get Alias here.");
+            var links = getSymbolLinks(symbol);
+            if (!links.target) {
+                links.target = resolvingSymbol;
+                var node = getDeclarationOfAliasSymbol(symbol);
+                if (!node)
+                    return ts.Debug.fail();
+                var target = getTargetOfAliasDeclaration(node);
+                if (links.target === resolvingSymbol) {
+                    links.target = target || unknownSymbol;
+                }
+                else {
+                    error(node, ts.Diagnostics.Circular_definition_of_import_alias_0, symbolToString(symbol));
+                }
+            }
+            else if (links.target === resolvingSymbol) {
+                links.target = unknownSymbol;
+            }
+            return links.target;
+        }
+        function markExportAsReferenced(node) {
+            var symbol = getSymbolOfNode(node);
+            var target = resolveAlias(symbol);
+            if (target) {
+                var markAlias = target === unknownSymbol ||
+                    ((target.flags & 67216319 /* Value */) && !isConstEnumOrConstEnumOnlyModule(target));
+                if (markAlias) {
+                    markAliasSymbolAsReferenced(symbol);
+                }
+            }
+        }
+        // When an alias symbol is referenced, we need to mark the entity it references as referenced and in turn repeat that until
+        // we reach a non-alias or an exported entity (which is always considered referenced). We do this by checking the target of
+        // the alias as an expression (which recursively takes us back here if the target references another alias).
+        function markAliasSymbolAsReferenced(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (!links.referenced) {
+                links.referenced = true;
+                var node = getDeclarationOfAliasSymbol(symbol);
+                if (!node)
+                    return ts.Debug.fail();
+                if (node.kind === 249 /* ExportAssignment */) {
+                    // export default <symbol>
+                    checkExpressionCached(node.expression);
+                }
+                else if (node.kind === 252 /* ExportSpecifier */) {
+                    // export { <symbol> } or export { <symbol> as foo }
+                    checkExpressionCached(node.propertyName || node.name);
+                }
+                else if (ts.isInternalModuleImportEqualsDeclaration(node)) {
+                    // import foo = <symbol>
+                    checkExpressionCached(node.moduleReference);
+                }
+            }
+        }
+        // This function is only for imports with entity names
+        function getSymbolOfPartOfRightHandSideOfImportEquals(entityName, dontResolveAlias) {
+            // There are three things we might try to look for. In the following examples,
+            // the search term is enclosed in |...|:
+            //
+            //     import a = |b|; // Namespace
+            //     import a = |b.c|; // Value, type, namespace
+            //     import a = |b.c|.d; // Namespace
+            if (entityName.kind === 71 /* Identifier */ && ts.isRightSideOfQualifiedNameOrPropertyAccess(entityName)) {
+                entityName = entityName.parent;
+            }
+            // Check for case 1 and 3 in the above example
+            if (entityName.kind === 71 /* Identifier */ || entityName.parent.kind === 146 /* QualifiedName */) {
+                return resolveEntityName(entityName, 1920 /* Namespace */, /*ignoreErrors*/ false, dontResolveAlias);
+            }
+            else {
+                // Case 2 in above example
+                // entityName.kind could be a QualifiedName or a Missing identifier
+                ts.Debug.assert(entityName.parent.kind === 243 /* ImportEqualsDeclaration */);
+                return resolveEntityName(entityName, 67216319 /* Value */ | 67901928 /* Type */ | 1920 /* Namespace */, /*ignoreErrors*/ false, dontResolveAlias);
+            }
+        }
+        function getFullyQualifiedName(symbol) {
+            return symbol.parent ? getFullyQualifiedName(symbol.parent) + "." + symbolToString(symbol) : symbolToString(symbol);
+        }
+        /**
+         * Resolves a qualified name and any involved aliases.
+         */
+        function resolveEntityName(name, meaning, ignoreErrors, dontResolveAlias, location) {
+            if (ts.nodeIsMissing(name)) {
+                return undefined;
+            }
+            var namespaceMeaning = 1920 /* Namespace */ | (ts.isInJavaScriptFile(name) ? meaning & 67216319 /* Value */ : 0);
+            var symbol;
+            if (name.kind === 71 /* Identifier */) {
+                var message = meaning === namespaceMeaning ? ts.Diagnostics.Cannot_find_namespace_0 : ts.Diagnostics.Cannot_find_name_0;
+                var symbolFromJSPrototype = ts.isInJavaScriptFile(name) ? resolveEntityNameFromJSSpecialAssignment(name, meaning) : undefined;
+                symbol = resolveName(location || name, name.escapedText, meaning, ignoreErrors || symbolFromJSPrototype ? undefined : message, name, /*isUse*/ true);
+                if (!symbol) {
+                    return symbolFromJSPrototype;
+                }
+            }
+            else if (name.kind === 146 /* QualifiedName */ || name.kind === 185 /* PropertyAccessExpression */) {
+                var left = name.kind === 146 /* QualifiedName */ ? name.left : name.expression;
+                var right = name.kind === 146 /* QualifiedName */ ? name.right : name.name;
+                var namespace = resolveEntityName(left, namespaceMeaning, ignoreErrors, /*dontResolveAlias*/ false, location);
+                if (!namespace || ts.nodeIsMissing(right)) {
+                    return undefined;
+                }
+                else if (namespace === unknownSymbol) {
+                    return namespace;
+                }
+                if (ts.isInJavaScriptFile(name)) {
+                    if (namespace.valueDeclaration &&
+                        ts.isVariableDeclaration(namespace.valueDeclaration) &&
+                        namespace.valueDeclaration.initializer &&
+                        isCommonJsRequire(namespace.valueDeclaration.initializer)) {
+                        var moduleName = namespace.valueDeclaration.initializer.arguments[0];
+                        var moduleSym = resolveExternalModuleName(moduleName, moduleName);
+                        if (moduleSym) {
+                            var resolvedModuleSymbol = resolveExternalModuleSymbol(moduleSym);
+                            if (resolvedModuleSymbol) {
+                                namespace = resolvedModuleSymbol;
+                            }
+                        }
+                    }
+                }
+                symbol = getSymbol(getExportsOfSymbol(namespace), right.escapedText, meaning);
+                if (!symbol) {
+                    if (!ignoreErrors) {
+                        error(right, ts.Diagnostics.Namespace_0_has_no_exported_member_1, getFullyQualifiedName(namespace), ts.declarationNameToString(right));
+                    }
+                    return undefined;
+                }
+            }
+            else {
+                throw ts.Debug.assertNever(name, "Unknown entity name kind.");
+            }
+            ts.Debug.assert((ts.getCheckFlags(symbol) & 1 /* Instantiated */) === 0, "Should never get an instantiated symbol here.");
+            return (symbol.flags & meaning) || dontResolveAlias ? symbol : resolveAlias(symbol);
+        }
+        /**
+         * 1. For prototype-property methods like `A.prototype.m = function () ...`, try to resolve names in the scope of `A` too.
+         * Note that prototype-property assignment to locations outside the current file (eg globals) doesn't work, so
+         * name resolution won't work either.
+         * 2. For property assignments like `{ x: function f () { } }`, try to resolve names in the scope of `f` too.
+         */
+        function resolveEntityNameFromJSSpecialAssignment(name, meaning) {
+            if (isJSDocTypeReference(name.parent)) {
+                var secondaryLocation = getJSSpecialAssignmentLocation(name.parent);
+                if (secondaryLocation) {
+                    return resolveName(secondaryLocation, name.escapedText, meaning, /*nameNotFoundMessage*/ undefined, name, /*isUse*/ true);
+                }
+            }
+        }
+        function getJSSpecialAssignmentLocation(node) {
+            var typeAlias = ts.findAncestor(node, function (node) { return !(ts.isJSDocNode(node) || node.flags & 2097152 /* JSDoc */) ? "quit" : ts.isJSDocTypeAlias(node); });
+            if (typeAlias) {
+                return;
+            }
+            var host = ts.getJSDocHost(node);
+            if (ts.isExpressionStatement(host) &&
+                ts.isBinaryExpression(host.expression) &&
+                ts.getSpecialPropertyAssignmentKind(host.expression) === 3 /* PrototypeProperty */) {
+                var symbol = getSymbolOfNode(host.expression.left);
+                return symbol && symbol.parent.valueDeclaration;
+            }
+            var sig = ts.getHostSignatureFromJSDocHost(host);
+            if (sig) {
+                var symbol = getSymbolOfNode(sig);
+                return symbol && symbol.valueDeclaration;
+            }
+        }
+        function resolveExternalModuleName(location, moduleReferenceExpression) {
+            return resolveExternalModuleNameWorker(location, moduleReferenceExpression, ts.Diagnostics.Cannot_find_module_0);
+        }
+        function resolveExternalModuleNameWorker(location, moduleReferenceExpression, moduleNotFoundError, isForAugmentation) {
+            if (isForAugmentation === void 0) { isForAugmentation = false; }
+            return ts.isStringLiteralLike(moduleReferenceExpression)
+                ? resolveExternalModule(location, moduleReferenceExpression.text, moduleNotFoundError, moduleReferenceExpression, isForAugmentation)
+                : undefined;
+        }
+        function resolveExternalModule(location, moduleReference, moduleNotFoundError, errorNode, isForAugmentation) {
+            if (isForAugmentation === void 0) { isForAugmentation = false; }
+            if (moduleReference === undefined) {
+                return;
+            }
+            if (ts.startsWith(moduleReference, "@types/")) {
+                var diag = ts.Diagnostics.Cannot_import_type_declaration_files_Consider_importing_0_instead_of_1;
+                var withoutAtTypePrefix = ts.removePrefix(moduleReference, "@types/");
+                error(errorNode, diag, withoutAtTypePrefix, moduleReference);
+            }
+            var ambientModule = tryFindAmbientModule(moduleReference, /*withAugmentations*/ true);
+            if (ambientModule) {
+                return ambientModule;
+            }
+            var currentSourceFile = ts.getSourceFileOfNode(location);
+            var resolvedModule = ts.getResolvedModule(currentSourceFile, moduleReference); // TODO: GH#18217
+            var resolutionDiagnostic = resolvedModule && ts.getResolutionDiagnostic(compilerOptions, resolvedModule);
+            var sourceFile = resolvedModule && !resolutionDiagnostic && host.getSourceFile(resolvedModule.resolvedFileName);
+            if (sourceFile) {
+                if (sourceFile.symbol) {
+                    if (resolvedModule.isExternalLibraryImport && !ts.extensionIsTypeScript(resolvedModule.extension)) {
+                        errorOnImplicitAnyModule(/*isError*/ false, errorNode, resolvedModule, moduleReference);
+                    }
+                    // merged symbol is module declaration symbol combined with all augmentations
+                    return getMergedSymbol(sourceFile.symbol);
+                }
+                if (moduleNotFoundError) {
+                    // report errors only if it was requested
+                    error(errorNode, ts.Diagnostics.File_0_is_not_a_module, sourceFile.fileName);
+                }
+                return undefined;
+            }
+            if (patternAmbientModules) {
+                var pattern = ts.findBestPatternMatch(patternAmbientModules, function (_) { return _.pattern; }, moduleReference);
+                if (pattern) {
+                    return getMergedSymbol(pattern.symbol);
+                }
+            }
+            // May be an untyped module. If so, ignore resolutionDiagnostic.
+            if (resolvedModule && !ts.resolutionExtensionIsTypeScriptOrJson(resolvedModule.extension) && resolutionDiagnostic === undefined || resolutionDiagnostic === ts.Diagnostics.Could_not_find_a_declaration_file_for_module_0_1_implicitly_has_an_any_type) {
+                if (isForAugmentation) {
+                    var diag = ts.Diagnostics.Invalid_module_name_in_augmentation_Module_0_resolves_to_an_untyped_module_at_1_which_cannot_be_augmented;
+                    error(errorNode, diag, moduleReference, resolvedModule.resolvedFileName);
+                }
+                else {
+                    errorOnImplicitAnyModule(/*isError*/ noImplicitAny && !!moduleNotFoundError, errorNode, resolvedModule, moduleReference);
+                }
+                // Failed imports and untyped modules are both treated in an untyped manner; only difference is whether we give a diagnostic first.
+                return undefined;
+            }
+            if (moduleNotFoundError) {
+                // For relative paths, see if this was possibly a projectReference redirect
+                if (ts.pathIsRelative(moduleReference)) {
+                    var sourceFile_1 = ts.getSourceFileOfNode(location);
+                    var redirects = sourceFile_1.redirectedReferences;
+                    if (redirects) {
+                        var normalizedTargetPath = ts.getNormalizedAbsolutePath(moduleReference, ts.getDirectoryPath(sourceFile_1.fileName));
+                        for (var _i = 0, _a = [".ts" /* Ts */, ".tsx" /* Tsx */]; _i < _a.length; _i++) {
+                            var ext = _a[_i];
+                            var probePath = normalizedTargetPath + ext;
+                            if (redirects.indexOf(probePath) >= 0) {
+                                error(errorNode, ts.Diagnostics.Output_file_0_has_not_been_built_from_source_file_1, moduleReference, probePath);
+                                return undefined;
+                            }
+                        }
+                    }
+                }
+                if (resolutionDiagnostic) {
+                    error(errorNode, resolutionDiagnostic, moduleReference, resolvedModule.resolvedFileName);
+                }
+                else {
+                    var tsExtension = ts.tryExtractTypeScriptExtension(moduleReference);
+                    if (tsExtension) {
+                        var diag = ts.Diagnostics.An_import_path_cannot_end_with_a_0_extension_Consider_importing_1_instead;
+                        error(errorNode, diag, tsExtension, ts.removeExtension(moduleReference, tsExtension));
+                    }
+                    else {
+                        error(errorNode, moduleNotFoundError, moduleReference);
+                    }
+                }
+            }
+            return undefined;
+        }
+        function errorOnImplicitAnyModule(isError, errorNode, _a, moduleReference) {
+            var packageId = _a.packageId, resolvedFileName = _a.resolvedFileName;
+            var errorInfo = packageId && ts.chainDiagnosticMessages(
+            /*details*/ undefined, ts.Diagnostics.Try_npm_install_types_Slash_0_if_it_exists_or_add_a_new_declaration_d_ts_file_containing_declare_module_0, ts.getMangledNameForScopedPackage(packageId.name));
+            errorOrSuggestion(isError, errorNode, ts.chainDiagnosticMessages(errorInfo, ts.Diagnostics.Could_not_find_a_declaration_file_for_module_0_1_implicitly_has_an_any_type, moduleReference, resolvedFileName));
+        }
+        function resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias) {
+            return moduleSymbol && getMergedSymbol(getCommonJsExportEquals(resolveSymbol(moduleSymbol.exports.get("export=" /* ExportEquals */), dontResolveAlias), moduleSymbol)) || moduleSymbol;
+        }
+        function getCommonJsExportEquals(exported, moduleSymbol) {
+            if (!exported || moduleSymbol.exports.size === 1) {
+                return exported;
+            }
+            var merged = cloneSymbol(exported);
+            if (merged.exports === undefined) {
+                merged.flags = merged.flags | 512 /* ValueModule */;
+                merged.exports = ts.createSymbolTable();
+            }
+            moduleSymbol.exports.forEach(function (s, name) {
+                if (name === "export=" /* ExportEquals */)
+                    return;
+                merged.exports.set(name, merged.exports.has(name) ? mergeSymbol(merged.exports.get(name), s) : s);
+            });
+            return merged;
+        }
+        // An external module with an 'export =' declaration may be referenced as an ES6 module provided the 'export ='
+        // references a symbol that is at least declared as a module or a variable. The target of the 'export =' may
+        // combine other declarations with the module or variable (e.g. a class/module, function/module, interface/variable).
+        function resolveESModuleSymbol(moduleSymbol, referencingLocation, dontResolveAlias) {
+            var symbol = resolveExternalModuleSymbol(moduleSymbol, dontResolveAlias);
+            if (!dontResolveAlias && symbol) {
+                if (!(symbol.flags & (1536 /* Module */ | 3 /* Variable */))) {
+                    error(referencingLocation, ts.Diagnostics.Module_0_resolves_to_a_non_module_entity_and_cannot_be_imported_using_this_construct, symbolToString(moduleSymbol));
+                    return symbol;
+                }
+                if (compilerOptions.esModuleInterop) {
+                    var referenceParent = referencingLocation.parent;
+                    if ((ts.isImportDeclaration(referenceParent) && ts.getNamespaceDeclarationNode(referenceParent)) ||
+                        ts.isImportCall(referenceParent)) {
+                        var type = getTypeOfSymbol(symbol);
+                        var sigs = getSignaturesOfStructuredType(type, 0 /* Call */);
+                        if (!sigs || !sigs.length) {
+                            sigs = getSignaturesOfStructuredType(type, 1 /* Construct */);
+                        }
+                        if (sigs && sigs.length) {
+                            var moduleType = getTypeWithSyntheticDefaultImportType(type, symbol, moduleSymbol);
+                            // Create a new symbol which has the module's type less the call and construct signatures
+                            var result = createSymbol(symbol.flags, symbol.escapedName);
+                            result.declarations = symbol.declarations ? symbol.declarations.slice() : [];
+                            result.parent = symbol.parent;
+                            result.target = symbol;
+                            result.originatingImport = referenceParent;
+                            if (symbol.valueDeclaration)
+                                result.valueDeclaration = symbol.valueDeclaration;
+                            if (symbol.constEnumOnlyModule)
+                                result.constEnumOnlyModule = true;
+                            if (symbol.members)
+                                result.members = ts.cloneMap(symbol.members);
+                            if (symbol.exports)
+                                result.exports = ts.cloneMap(symbol.exports);
+                            var resolvedModuleType = resolveStructuredTypeMembers(moduleType); // Should already be resolved from the signature checks above
+                            result.type = createAnonymousType(result, resolvedModuleType.members, ts.emptyArray, ts.emptyArray, resolvedModuleType.stringIndexInfo, resolvedModuleType.numberIndexInfo);
+                            return result;
+                        }
+                    }
+                }
+            }
+            return symbol;
+        }
+        function hasExportAssignmentSymbol(moduleSymbol) {
+            return moduleSymbol.exports.get("export=" /* ExportEquals */) !== undefined;
+        }
+        function getExportsOfModuleAsArray(moduleSymbol) {
+            return symbolsToArray(getExportsOfModule(moduleSymbol));
+        }
+        function getExportsAndPropertiesOfModule(moduleSymbol) {
+            var exports = getExportsOfModuleAsArray(moduleSymbol);
+            var exportEquals = resolveExternalModuleSymbol(moduleSymbol);
+            if (exportEquals !== moduleSymbol) {
+                ts.addRange(exports, getPropertiesOfType(getTypeOfSymbol(exportEquals)));
+            }
+            return exports;
+        }
+        function tryGetMemberInModuleExports(memberName, moduleSymbol) {
+            var symbolTable = getExportsOfModule(moduleSymbol);
+            if (symbolTable) {
+                return symbolTable.get(memberName);
+            }
+        }
+        function tryGetMemberInModuleExportsAndProperties(memberName, moduleSymbol) {
+            var symbol = tryGetMemberInModuleExports(memberName, moduleSymbol);
+            if (symbol) {
+                return symbol;
+            }
+            var exportEquals = resolveExternalModuleSymbol(moduleSymbol);
+            if (exportEquals === moduleSymbol) {
+                return undefined;
+            }
+            var type = getTypeOfSymbol(exportEquals);
+            return type.flags & 32764 /* Primitive */ ? undefined : getPropertyOfType(type, memberName);
+        }
+        function getExportsOfSymbol(symbol) {
+            return symbol.flags & 32 /* Class */ ? getResolvedMembersOrExportsOfSymbol(symbol, "resolvedExports" /* resolvedExports */) :
+                symbol.flags & 1536 /* Module */ ? getExportsOfModule(symbol) :
+                    symbol.exports || emptySymbols;
+        }
+        function getExportsOfModule(moduleSymbol) {
+            var links = getSymbolLinks(moduleSymbol);
+            return links.resolvedExports || (links.resolvedExports = getExportsOfModuleWorker(moduleSymbol));
+        }
+        /**
+         * Extends one symbol table with another while collecting information on name collisions for error message generation into the `lookupTable` argument
+         * Not passing `lookupTable` and `exportNode` disables this collection, and just extends the tables
+         */
+        function extendExportSymbols(target, source, lookupTable, exportNode) {
+            if (!source)
+                return;
+            source.forEach(function (sourceSymbol, id) {
+                if (id === "default" /* Default */)
+                    return;
+                var targetSymbol = target.get(id);
+                if (!targetSymbol) {
+                    target.set(id, sourceSymbol);
+                    if (lookupTable && exportNode) {
+                        lookupTable.set(id, {
+                            specifierText: ts.getTextOfNode(exportNode.moduleSpecifier)
+                        });
+                    }
+                }
+                else if (lookupTable && exportNode && targetSymbol && resolveSymbol(targetSymbol) !== resolveSymbol(sourceSymbol)) {
+                    var collisionTracker = lookupTable.get(id);
+                    if (!collisionTracker.exportsWithDuplicate) {
+                        collisionTracker.exportsWithDuplicate = [exportNode];
+                    }
+                    else {
+                        collisionTracker.exportsWithDuplicate.push(exportNode);
+                    }
+                }
+            });
+        }
+        function getExportsOfModuleWorker(moduleSymbol) {
+            var visitedSymbols = [];
+            // A module defined by an 'export=' consists on one export that needs to be resolved
+            moduleSymbol = resolveExternalModuleSymbol(moduleSymbol);
+            return visit(moduleSymbol) || emptySymbols;
+            // The ES6 spec permits export * declarations in a module to circularly reference the module itself. For example,
+            // module 'a' can 'export * from "b"' and 'b' can 'export * from "a"' without error.
+            function visit(symbol) {
+                if (!(symbol && symbol.flags & 1955 /* HasExports */ && ts.pushIfUnique(visitedSymbols, symbol))) {
+                    return;
+                }
+                var symbols = ts.cloneMap(symbol.exports);
+                // All export * declarations are collected in an __export symbol by the binder
+                var exportStars = symbol.exports.get("__export" /* ExportStar */);
+                if (exportStars) {
+                    var nestedSymbols = ts.createSymbolTable();
+                    var lookupTable_1 = ts.createMap();
+                    for (var _i = 0, _a = exportStars.declarations; _i < _a.length; _i++) {
+                        var node = _a[_i];
+                        var resolvedModule = resolveExternalModuleName(node, node.moduleSpecifier);
+                        var exportedSymbols = visit(resolvedModule);
+                        extendExportSymbols(nestedSymbols, exportedSymbols, lookupTable_1, node);
+                    }
+                    lookupTable_1.forEach(function (_a, id) {
+                        var exportsWithDuplicate = _a.exportsWithDuplicate;
+                        // It's not an error if the file with multiple `export *`s with duplicate names exports a member with that name itself
+                        if (id === "export=" || !(exportsWithDuplicate && exportsWithDuplicate.length) || symbols.has(id)) {
+                            return;
+                        }
+                        for (var _i = 0, exportsWithDuplicate_1 = exportsWithDuplicate; _i < exportsWithDuplicate_1.length; _i++) {
+                            var node = exportsWithDuplicate_1[_i];
+                            diagnostics.add(ts.createDiagnosticForNode(node, ts.Diagnostics.Module_0_has_already_exported_a_member_named_1_Consider_explicitly_re_exporting_to_resolve_the_ambiguity, lookupTable_1.get(id).specifierText, ts.unescapeLeadingUnderscores(id)));
+                        }
+                    });
+                    extendExportSymbols(symbols, nestedSymbols);
+                }
+                return symbols;
+            }
+        }
+        function getMergedSymbol(symbol) {
+            var merged;
+            return symbol && symbol.mergeId && (merged = mergedSymbols[symbol.mergeId]) ? merged : symbol;
+        }
+        function getSymbolOfNode(node) {
+            return getMergedSymbol(node.symbol && getLateBoundSymbol(node.symbol));
+        }
+        function getParentOfSymbol(symbol) {
+            return getMergedSymbol(symbol.parent && getLateBoundSymbol(symbol.parent));
+        }
+        /**
+         * Attempts to find the symbol corresponding to the container a symbol is in - usually this
+         * is just its' `.parent`, but for locals, this value is `undefined`
+         */
+        function getContainerOfSymbol(symbol) {
+            var container = getParentOfSymbol(symbol);
+            if (container) {
+                return container;
+            }
+            var candidate = ts.forEach(symbol.declarations, function (d) { return !ts.isAmbientModule(d) && d.parent && hasNonGlobalAugmentationExternalModuleSymbol(d.parent) ? getSymbolOfNode(d.parent) : undefined; });
+            if (!candidate) {
+                return undefined;
+            }
+            var alias = getAliasForSymbolInContainer(candidate, symbol);
+            return alias ? candidate : undefined;
+        }
+        function getAliasForSymbolInContainer(container, symbol) {
+            if (container === getParentOfSymbol(symbol)) {
+                // fast path, `symbol` is either already the alias or isn't aliased
+                return symbol;
+            }
+            var exports = getExportsOfSymbol(container);
+            var quick = exports.get(symbol.escapedName);
+            if (quick && symbolRefersToTarget(quick)) {
+                return quick;
+            }
+            return ts.forEachEntry(exports, function (exported) {
+                if (symbolRefersToTarget(exported)) {
+                    return exported;
+                }
+            });
+            function symbolRefersToTarget(s) {
+                if (s === symbol || resolveSymbol(s) === symbol || resolveSymbol(s) === resolveSymbol(symbol)) {
+                    return s;
+                }
+            }
+        }
+        function getExportSymbolOfValueSymbolIfExported(symbol) {
+            return symbol && (symbol.flags & 1048576 /* ExportValue */) !== 0
+                ? getMergedSymbol(symbol.exportSymbol)
+                : symbol;
+        }
+        function symbolIsValue(symbol) {
+            return !!(symbol.flags & 67216319 /* Value */ || symbol.flags & 2097152 /* Alias */ && resolveAlias(symbol).flags & 67216319 /* Value */);
+        }
+        function findConstructorDeclaration(node) {
+            var members = node.members;
+            for (var _i = 0, members_2 = members; _i < members_2.length; _i++) {
+                var member = members_2[_i];
+                if (member.kind === 155 /* Constructor */ && ts.nodeIsPresent(member.body)) {
+                    return member;
+                }
+            }
+        }
+        function createType(flags) {
+            var result = new Type(checker, flags);
+            typeCount++;
+            result.id = typeCount;
+            return result;
+        }
+        function createIntrinsicType(kind, intrinsicName) {
+            var type = createType(kind);
+            type.intrinsicName = intrinsicName;
+            return type;
+        }
+        function createBooleanType(trueFalseTypes) {
+            var type = getUnionType(trueFalseTypes);
+            type.flags |= 16 /* Boolean */;
+            type.intrinsicName = "boolean";
+            return type;
+        }
+        function createObjectType(objectFlags, symbol) {
+            var type = createType(131072 /* Object */);
+            type.objectFlags = objectFlags;
+            type.symbol = symbol;
+            return type;
+        }
+        function createTypeofType() {
+            return getUnionType(ts.arrayFrom(typeofEQFacts.keys(), getLiteralType));
+        }
+        // A reserved member name starts with two underscores, but the third character cannot be an underscore
+        // or the @ symbol. A third underscore indicates an escaped form of an identifer that started
+        // with at least two underscores. The @ character indicates that the name is denoted by a well known ES
+        // Symbol instance.
+        function isReservedMemberName(name) {
+            return name.charCodeAt(0) === 95 /* _ */ &&
+                name.charCodeAt(1) === 95 /* _ */ &&
+                name.charCodeAt(2) !== 95 /* _ */ &&
+                name.charCodeAt(2) !== 64 /* at */;
+        }
+        function getNamedMembers(members) {
+            var result;
+            members.forEach(function (symbol, id) {
+                if (!isReservedMemberName(id)) {
+                    if (!result)
+                        result = [];
+                    if (symbolIsValue(symbol)) {
+                        result.push(symbol);
+                    }
+                }
+            });
+            return result || ts.emptyArray;
+        }
+        function setStructuredTypeMembers(type, members, callSignatures, constructSignatures, stringIndexInfo, numberIndexInfo) {
+            type.members = members;
+            type.properties = getNamedMembers(members);
+            type.callSignatures = callSignatures;
+            type.constructSignatures = constructSignatures;
+            if (stringIndexInfo)
+                type.stringIndexInfo = stringIndexInfo;
+            if (numberIndexInfo)
+                type.numberIndexInfo = numberIndexInfo;
+            return type;
+        }
+        function createAnonymousType(symbol, members, callSignatures, constructSignatures, stringIndexInfo, numberIndexInfo) {
+            return setStructuredTypeMembers(createObjectType(16 /* Anonymous */, symbol), members, callSignatures, constructSignatures, stringIndexInfo, numberIndexInfo);
+        }
+        function forEachSymbolTableInScope(enclosingDeclaration, callback) {
+            var result;
+            for (var location = enclosingDeclaration; location; location = location.parent) {
+                // Locals of a source file are not in scope (because they get merged into the global symbol table)
+                if (location.locals && !isGlobalSourceFile(location)) {
+                    if (result = callback(location.locals)) {
+                        return result;
+                    }
+                }
+                switch (location.kind) {
+                    case 274 /* SourceFile */:
+                        if (!ts.isExternalOrCommonJsModule(location)) {
+                            break;
+                        }
+                    // falls through
+                    case 239 /* ModuleDeclaration */:
+                        if (result = callback(getSymbolOfNode(location).exports)) {
+                            return result;
+                        }
+                        break;
+                }
+            }
+            return callback(globals);
+        }
+        function getQualifiedLeftMeaning(rightMeaning) {
+            // If we are looking in value space, the parent meaning is value, other wise it is namespace
+            return rightMeaning === 67216319 /* Value */ ? 67216319 /* Value */ : 1920 /* Namespace */;
+        }
+        function getAccessibleSymbolChain(symbol, enclosingDeclaration, meaning, useOnlyExternalAliasing, visitedSymbolTablesMap) {
+            if (visitedSymbolTablesMap === void 0) { visitedSymbolTablesMap = ts.createMap(); }
+            if (!(symbol && !isPropertyOrMethodDeclarationSymbol(symbol))) {
+                return undefined;
+            }
+            var id = "" + getSymbolId(symbol);
+            var visitedSymbolTables = visitedSymbolTablesMap.get(id);
+            if (!visitedSymbolTables) {
+                visitedSymbolTablesMap.set(id, visitedSymbolTables = []);
+            }
+            return forEachSymbolTableInScope(enclosingDeclaration, getAccessibleSymbolChainFromSymbolTable);
+            /**
+             * @param {ignoreQualification} boolean Set when a symbol is being looked for through the exports of another symbol (meaning we have a route to qualify it already)
+             */
+            function getAccessibleSymbolChainFromSymbolTable(symbols, ignoreQualification) {
+                if (!ts.pushIfUnique(visitedSymbolTables, symbols)) {
+                    return undefined;
+                }
+                var result = trySymbolTable(symbols, ignoreQualification);
+                visitedSymbolTables.pop();
+                return result;
+            }
+            function canQualifySymbol(symbolFromSymbolTable, meaning) {
+                // If the symbol is equivalent and doesn't need further qualification, this symbol is accessible
+                return !needsQualification(symbolFromSymbolTable, enclosingDeclaration, meaning) ||
+                    // If symbol needs qualification, make sure that parent is accessible, if it is then this symbol is accessible too
+                    !!getAccessibleSymbolChain(symbolFromSymbolTable.parent, enclosingDeclaration, getQualifiedLeftMeaning(meaning), useOnlyExternalAliasing, visitedSymbolTablesMap);
+            }
+            function isAccessible(symbolFromSymbolTable, resolvedAliasSymbol, ignoreQualification) {
+                return symbol === (resolvedAliasSymbol || symbolFromSymbolTable) &&
+                    // if the symbolFromSymbolTable is not external module (it could be if it was determined as ambient external module and would be in globals table)
+                    // and if symbolFromSymbolTable or alias resolution matches the symbol,
+                    // check the symbol can be qualified, it is only then this symbol is accessible
+                    !ts.some(symbolFromSymbolTable.declarations, hasNonGlobalAugmentationExternalModuleSymbol) &&
+                    (ignoreQualification || canQualifySymbol(symbolFromSymbolTable, meaning));
+            }
+            function trySymbolTable(symbols, ignoreQualification) {
+                // If symbol is directly available by its name in the symbol table
+                if (isAccessible(symbols.get(symbol.escapedName), /*resolvedAliasSymbol*/ undefined, ignoreQualification)) {
+                    return [symbol];
+                }
+                // Check if symbol is any of the alias
+                return ts.forEachEntry(symbols, function (symbolFromSymbolTable) {
+                    if (symbolFromSymbolTable.flags & 2097152 /* Alias */
+                        && symbolFromSymbolTable.escapedName !== "export=" /* ExportEquals */
+                        && symbolFromSymbolTable.escapedName !== "default" /* Default */
+                        && !(ts.isUMDExportSymbol(symbolFromSymbolTable) && enclosingDeclaration && ts.isExternalModule(ts.getSourceFileOfNode(enclosingDeclaration)))
+                        // If `!useOnlyExternalAliasing`, we can use any type of alias to get the name
+                        && (!useOnlyExternalAliasing || ts.some(symbolFromSymbolTable.declarations, ts.isExternalModuleImportEqualsDeclaration))) {
+                        var resolvedImportedSymbol = resolveAlias(symbolFromSymbolTable);
+                        if (isAccessible(symbolFromSymbolTable, resolvedImportedSymbol, ignoreQualification)) {
+                            return [symbolFromSymbolTable];
+                        }
+                        // Look in the exported members, if we can find accessibleSymbolChain, symbol is accessible using this chain
+                        // but only if the symbolFromSymbolTable can be qualified
+                        var candidateTable = getExportsOfSymbol(resolvedImportedSymbol);
+                        var accessibleSymbolsFromExports = candidateTable && getAccessibleSymbolChainFromSymbolTable(candidateTable, /*ignoreQualification*/ true);
+                        if (accessibleSymbolsFromExports && canQualifySymbol(symbolFromSymbolTable, getQualifiedLeftMeaning(meaning))) {
+                            return [symbolFromSymbolTable].concat(accessibleSymbolsFromExports);
+                        }
+                    }
+                    if (symbolFromSymbolTable.escapedName === symbol.escapedName && symbolFromSymbolTable.exportSymbol) {
+                        if (isAccessible(getMergedSymbol(symbolFromSymbolTable.exportSymbol), /*aliasSymbol*/ undefined, ignoreQualification)) {
+                            return [symbol];
+                        }
+                    }
+                });
+            }
+        }
+        function needsQualification(symbol, enclosingDeclaration, meaning) {
+            var qualify = false;
+            forEachSymbolTableInScope(enclosingDeclaration, function (symbolTable) {
+                // If symbol of this name is not available in the symbol table we are ok
+                var symbolFromSymbolTable = getMergedSymbol(symbolTable.get(symbol.escapedName));
+                if (!symbolFromSymbolTable) {
+                    // Continue to the next symbol table
+                    return false;
+                }
+                // If the symbol with this name is present it should refer to the symbol
+                if (symbolFromSymbolTable === symbol) {
+                    // No need to qualify
+                    return true;
+                }
+                // Qualify if the symbol from symbol table has same meaning as expected
+                symbolFromSymbolTable = (symbolFromSymbolTable.flags & 2097152 /* Alias */ && !ts.getDeclarationOfKind(symbolFromSymbolTable, 252 /* ExportSpecifier */)) ? resolveAlias(symbolFromSymbolTable) : symbolFromSymbolTable;
+                if (symbolFromSymbolTable.flags & meaning) {
+                    qualify = true;
+                    return true;
+                }
+                // Continue to the next symbol table
+                return false;
+            });
+            return qualify;
+        }
+        function isPropertyOrMethodDeclarationSymbol(symbol) {
+            if (symbol.declarations && symbol.declarations.length) {
+                for (var _i = 0, _a = symbol.declarations; _i < _a.length; _i++) {
+                    var declaration = _a[_i];
+                    switch (declaration.kind) {
+                        case 152 /* PropertyDeclaration */:
+                        case 154 /* MethodDeclaration */:
+                        case 156 /* GetAccessor */:
+                        case 157 /* SetAccessor */:
+                            continue;
+                        default:
+                            return false;
+                    }
+                }
+                return true;
+            }
+            return false;
+        }
+        function isTypeSymbolAccessible(typeSymbol, enclosingDeclaration) {
+            var access = isSymbolAccessible(typeSymbol, enclosingDeclaration, 67901928 /* Type */, /*shouldComputeAliasesToMakeVisible*/ false);
+            return access.accessibility === 0 /* Accessible */;
+        }
+        function isValueSymbolAccessible(typeSymbol, enclosingDeclaration) {
+            var access = isSymbolAccessible(typeSymbol, enclosingDeclaration, 67216319 /* Value */, /*shouldComputeAliasesToMakeVisible*/ false);
+            return access.accessibility === 0 /* Accessible */;
+        }
+        /**
+         * Check if the given symbol in given enclosing declaration is accessible and mark all associated alias to be visible if requested
+         *
+         * @param symbol a Symbol to check if accessible
+         * @param enclosingDeclaration a Node containing reference to the symbol
+         * @param meaning a SymbolFlags to check if such meaning of the symbol is accessible
+         * @param shouldComputeAliasToMakeVisible a boolean value to indicate whether to return aliases to be mark visible in case the symbol is accessible
+         */
+        function isSymbolAccessible(symbol, enclosingDeclaration, meaning, shouldComputeAliasesToMakeVisible) {
+            if (symbol && enclosingDeclaration) {
+                var initialSymbol = symbol;
+                var meaningToLook = meaning;
+                while (symbol) {
+                    // Symbol is accessible if it by itself is accessible
+                    var accessibleSymbolChain = getAccessibleSymbolChain(symbol, enclosingDeclaration, meaningToLook, /*useOnlyExternalAliasing*/ false);
+                    if (accessibleSymbolChain) {
+                        var hasAccessibleDeclarations = hasVisibleDeclarations(accessibleSymbolChain[0], shouldComputeAliasesToMakeVisible);
+                        if (!hasAccessibleDeclarations) {
+                            return {
+                                accessibility: 1 /* NotAccessible */,
+                                errorSymbolName: symbolToString(initialSymbol, enclosingDeclaration, meaning),
+                                errorModuleName: symbol !== initialSymbol ? symbolToString(symbol, enclosingDeclaration, 1920 /* Namespace */) : undefined,
+                            };
+                        }
+                        return hasAccessibleDeclarations;
+                    }
+                    else {
+                        if (ts.some(symbol.declarations, hasNonGlobalAugmentationExternalModuleSymbol)) {
+                            // Any meaning of a module symbol is always accessible via an `import` type
+                            return {
+                                accessibility: 0 /* Accessible */
+                            };
+                        }
+                    }
+                    // If we haven't got the accessible symbol, it doesn't mean the symbol is actually inaccessible.
+                    // It could be a qualified symbol and hence verify the path
+                    // e.g.:
+                    // module m {
+                    //     export class c {
+                    //     }
+                    // }
+                    // const x: typeof m.c
+                    // In the above example when we start with checking if typeof m.c symbol is accessible,
+                    // we are going to see if c can be accessed in scope directly.
+                    // But it can't, hence the accessible is going to be undefined, but that doesn't mean m.c is inaccessible
+                    // It is accessible if the parent m is accessible because then m.c can be accessed through qualification
+                    meaningToLook = getQualifiedLeftMeaning(meaning);
+                    symbol = getContainerOfSymbol(symbol);
+                }
+                // This could be a symbol that is not exported in the external module
+                // or it could be a symbol from different external module that is not aliased and hence cannot be named
+                var symbolExternalModule = ts.forEach(initialSymbol.declarations, getExternalModuleContainer);
+                if (symbolExternalModule) {
+                    var enclosingExternalModule = getExternalModuleContainer(enclosingDeclaration);
+                    if (symbolExternalModule !== enclosingExternalModule) {
+                        // name from different external module that is not visible
+                        return {
+                            accessibility: 2 /* CannotBeNamed */,
+                            errorSymbolName: symbolToString(initialSymbol, enclosingDeclaration, meaning),
+                            errorModuleName: symbolToString(symbolExternalModule)
+                        };
+                    }
+                }
+                // Just a local name that is not accessible
+                return {
+                    accessibility: 1 /* NotAccessible */,
+                    errorSymbolName: symbolToString(initialSymbol, enclosingDeclaration, meaning),
+                };
+            }
+            return { accessibility: 0 /* Accessible */ };
+            function getExternalModuleContainer(declaration) {
+                var node = ts.findAncestor(declaration, hasExternalModuleSymbol);
+                return node && getSymbolOfNode(node);
+            }
+        }
+        function hasExternalModuleSymbol(declaration) {
+            return ts.isAmbientModule(declaration) || (declaration.kind === 274 /* SourceFile */ && ts.isExternalOrCommonJsModule(declaration));
+        }
+        function hasNonGlobalAugmentationExternalModuleSymbol(declaration) {
+            return ts.isModuleWithStringLiteralName(declaration) || (declaration.kind === 274 /* SourceFile */ && ts.isExternalOrCommonJsModule(declaration));
+        }
+        function hasVisibleDeclarations(symbol, shouldComputeAliasToMakeVisible) {
+            var aliasesToMakeVisible;
+            if (!ts.every(symbol.declarations, getIsDeclarationVisible)) {
+                return undefined;
+            }
+            return { accessibility: 0 /* Accessible */, aliasesToMakeVisible: aliasesToMakeVisible };
+            function getIsDeclarationVisible(declaration) {
+                if (!isDeclarationVisible(declaration)) {
+                    // Mark the unexported alias as visible if its parent is visible
+                    // because these kind of aliases can be used to name types in declaration file
+                    var anyImportSyntax = getAnyImportSyntax(declaration);
+                    if (anyImportSyntax &&
+                        !ts.hasModifier(anyImportSyntax, 1 /* Export */) && // import clause without export
+                        isDeclarationVisible(anyImportSyntax.parent)) {
+                        return addVisibleAlias(declaration, anyImportSyntax);
+                    }
+                    else if (ts.isVariableDeclaration(declaration) && ts.isVariableStatement(declaration.parent.parent) &&
+                        !ts.hasModifier(declaration.parent.parent, 1 /* Export */) && // unexported variable statement
+                        isDeclarationVisible(declaration.parent.parent.parent)) {
+                        return addVisibleAlias(declaration, declaration.parent.parent);
+                    }
+                    else if (ts.isLateVisibilityPaintedStatement(declaration) // unexported top-level statement
+                        && !ts.hasModifier(declaration, 1 /* Export */)
+                        && isDeclarationVisible(declaration.parent)) {
+                        return addVisibleAlias(declaration, declaration);
+                    }
+                    // Declaration is not visible
+                    return false;
+                }
+                return true;
+            }
+            function addVisibleAlias(declaration, aliasingStatement) {
+                // In function "buildTypeDisplay" where we decide whether to write type-alias or serialize types,
+                // we want to just check if type- alias is accessible or not but we don't care about emitting those alias at that time
+                // since we will do the emitting later in trackSymbol.
+                if (shouldComputeAliasToMakeVisible) {
+                    getNodeLinks(declaration).isVisible = true;
+                    aliasesToMakeVisible = ts.appendIfUnique(aliasesToMakeVisible, aliasingStatement);
+                }
+                return true;
+            }
+        }
+        function isEntityNameVisible(entityName, enclosingDeclaration) {
+            // get symbol of the first identifier of the entityName
+            var meaning;
+            if (entityName.parent.kind === 165 /* TypeQuery */ ||
+                ts.isExpressionWithTypeArgumentsInClassExtendsClause(entityName.parent) ||
+                entityName.parent.kind === 147 /* ComputedPropertyName */) {
+                // Typeof value
+                meaning = 67216319 /* Value */ | 1048576 /* ExportValue */;
+            }
+            else if (entityName.kind === 146 /* QualifiedName */ || entityName.kind === 185 /* PropertyAccessExpression */ ||
+                entityName.parent.kind === 243 /* ImportEqualsDeclaration */) {
+                // Left identifier from type reference or TypeAlias
+                // Entity name of the import declaration
+                meaning = 1920 /* Namespace */;
+            }
+            else {
+                // Type Reference or TypeAlias entity = Identifier
+                meaning = 67901928 /* Type */;
+            }
+            var firstIdentifier = getFirstIdentifier(entityName);
+            var symbol = resolveName(enclosingDeclaration, firstIdentifier.escapedText, meaning, /*nodeNotFoundErrorMessage*/ undefined, /*nameArg*/ undefined, /*isUse*/ false);
+            // Verify if the symbol is accessible
+            return (symbol && hasVisibleDeclarations(symbol, /*shouldComputeAliasToMakeVisible*/ true)) || {
+                accessibility: 1 /* NotAccessible */,
+                errorSymbolName: ts.getTextOfNode(firstIdentifier),
+                errorNode: firstIdentifier
+            };
+        }
+        function symbolToString(symbol, enclosingDeclaration, meaning, flags, writer) {
+            if (flags === void 0) { flags = 4 /* AllowAnyNodeKind */; }
+            var nodeFlags = 3112960 /* IgnoreErrors */;
+            if (flags & 2 /* UseOnlyExternalAliasing */) {
+                nodeFlags |= 128 /* UseOnlyExternalAliasing */;
+            }
+            if (flags & 1 /* WriteTypeParametersOrArguments */) {
+                nodeFlags |= 512 /* WriteTypeParametersInQualifiedName */;
+            }
+            if (flags & 8 /* UseAliasDefinedOutsideCurrentScope */) {
+                nodeFlags |= 16384 /* UseAliasDefinedOutsideCurrentScope */;
+            }
+            var builder = flags & 4 /* AllowAnyNodeKind */ ? nodeBuilder.symbolToExpression : nodeBuilder.symbolToEntityName;
+            return writer ? symbolToStringWorker(writer).getText() : ts.usingSingleLineStringWriter(symbolToStringWorker);
+            function symbolToStringWorker(writer) {
+                var entity = builder(symbol, meaning, enclosingDeclaration, nodeFlags); // TODO: GH#18217
+                var printer = ts.createPrinter({ removeComments: true });
+                var sourceFile = enclosingDeclaration && ts.getSourceFileOfNode(enclosingDeclaration);
+                printer.writeNode(4 /* Unspecified */, entity, /*sourceFile*/ sourceFile, writer);
+                return writer;
+            }
+        }
+        function signatureToString(signature, enclosingDeclaration, flags, kind, writer) {
+            if (flags === void 0) { flags = 0 /* None */; }
+            return writer ? signatureToStringWorker(writer).getText() : ts.usingSingleLineStringWriter(signatureToStringWorker);
+            function signatureToStringWorker(writer) {
+                var sigOutput;
+                if (flags & 262144 /* WriteArrowStyleSignature */) {
+                    sigOutput = kind === 1 /* Construct */ ? 164 /* ConstructorType */ : 163 /* FunctionType */;
+                }
+                else {
+                    sigOutput = kind === 1 /* Construct */ ? 159 /* ConstructSignature */ : 158 /* CallSignature */;
+                }
+                var sig = nodeBuilder.signatureToSignatureDeclaration(signature, sigOutput, enclosingDeclaration, toNodeBuilderFlags(flags) | 3112960 /* IgnoreErrors */ | 512 /* WriteTypeParametersInQualifiedName */);
+                var printer = ts.createPrinter({ removeComments: true, omitTrailingSemicolon: true });
+                var sourceFile = enclosingDeclaration && ts.getSourceFileOfNode(enclosingDeclaration);
+                printer.writeNode(4 /* Unspecified */, sig, /*sourceFile*/ sourceFile, writer); // TODO: GH#18217
+                return writer;
+            }
+        }
+        function typeToString(type, enclosingDeclaration, flags, writer) {
+            if (flags === void 0) { flags = 1048576 /* AllowUniqueESSymbolType */ | 16384 /* UseAliasDefinedOutsideCurrentScope */; }
+            if (writer === void 0) { writer = ts.createTextWriter(""); }
+            var typeNode = nodeBuilder.typeToTypeNode(type, enclosingDeclaration, toNodeBuilderFlags(flags) | 3112960 /* IgnoreErrors */, writer);
+            if (typeNode === undefined)
+                return ts.Debug.fail("should always get typenode");
+            var options = { removeComments: true };
+            var printer = ts.createPrinter(options);
+            var sourceFile = enclosingDeclaration && ts.getSourceFileOfNode(enclosingDeclaration);
+            printer.writeNode(4 /* Unspecified */, typeNode, /*sourceFile*/ sourceFile, writer);
+            var result = writer.getText();
+            var maxLength = compilerOptions.noErrorTruncation || flags & 1 /* NoTruncation */ ? undefined : 100;
+            if (maxLength && result && result.length >= maxLength) {
+                return result.substr(0, maxLength - "...".length) + "...";
+            }
+            return result;
+        }
+        function toNodeBuilderFlags(flags) {
+            if (flags === void 0) { flags = 0 /* None */; }
+            return flags & 9469291 /* NodeBuilderFlagsMask */;
+        }
+        function createNodeBuilder() {
+            return {
+                typeToTypeNode: function (type, enclosingDeclaration, flags, tracker) {
+                    ts.Debug.assert(enclosingDeclaration === undefined || (enclosingDeclaration.flags & 8 /* Synthesized */) === 0);
+                    var context = createNodeBuilderContext(enclosingDeclaration, flags, tracker);
+                    var resultingNode = typeToTypeNodeHelper(type, context);
+                    var result = context.encounteredError ? undefined : resultingNode;
+                    return result;
+                },
+                indexInfoToIndexSignatureDeclaration: function (indexInfo, kind, enclosingDeclaration, flags, tracker) {
+                    ts.Debug.assert(enclosingDeclaration === undefined || (enclosingDeclaration.flags & 8 /* Synthesized */) === 0);
+                    var context = createNodeBuilderContext(enclosingDeclaration, flags, tracker);
+                    var resultingNode = indexInfoToIndexSignatureDeclarationHelper(indexInfo, kind, context);
+                    var result = context.encounteredError ? undefined : resultingNode;
+                    return result; // TODO: GH#18217
+                },
+                signatureToSignatureDeclaration: function (signature, kind, enclosingDeclaration, flags, tracker) {
+                    ts.Debug.assert(enclosingDeclaration === undefined || (enclosingDeclaration.flags & 8 /* Synthesized */) === 0);
+                    var context = createNodeBuilderContext(enclosingDeclaration, flags, tracker);
+                    var resultingNode = signatureToSignatureDeclarationHelper(signature, kind, context);
+                    var result = context.encounteredError ? undefined : resultingNode;
+                    return result;
+                },
+                symbolToEntityName: function (symbol, meaning, enclosingDeclaration, flags, tracker) {
+                    ts.Debug.assert(enclosingDeclaration === undefined || (enclosingDeclaration.flags & 8 /* Synthesized */) === 0);
+                    var context = createNodeBuilderContext(enclosingDeclaration, flags, tracker);
+                    var resultingNode = symbolToName(symbol, context, meaning, /*expectsIdentifier*/ false);
+                    var result = context.encounteredError ? undefined : resultingNode;
+                    return result;
+                },
+                symbolToExpression: function (symbol, meaning, enclosingDeclaration, flags, tracker) {
+                    ts.Debug.assert(enclosingDeclaration === undefined || (enclosingDeclaration.flags & 8 /* Synthesized */) === 0);
+                    var context = createNodeBuilderContext(enclosingDeclaration, flags, tracker);
+                    var resultingNode = symbolToExpression(symbol, context, meaning);
+                    var result = context.encounteredError ? undefined : resultingNode;
+                    return result;
+                },
+                symbolToTypeParameterDeclarations: function (symbol, enclosingDeclaration, flags, tracker) {
+                    ts.Debug.assert(enclosingDeclaration === undefined || (enclosingDeclaration.flags & 8 /* Synthesized */) === 0);
+                    var context = createNodeBuilderContext(enclosingDeclaration, flags, tracker);
+                    var resultingNode = typeParametersToTypeParameterDeclarations(symbol, context);
+                    var result = context.encounteredError ? undefined : resultingNode;
+                    return result;
+                },
+                symbolToParameterDeclaration: function (symbol, enclosingDeclaration, flags, tracker) {
+                    ts.Debug.assert(enclosingDeclaration === undefined || (enclosingDeclaration.flags & 8 /* Synthesized */) === 0);
+                    var context = createNodeBuilderContext(enclosingDeclaration, flags, tracker);
+                    var resultingNode = symbolToParameterDeclaration(symbol, context);
+                    var result = context.encounteredError ? undefined : resultingNode;
+                    return result;
+                },
+                typeParameterToDeclaration: function (parameter, enclosingDeclaration, flags, tracker) {
+                    ts.Debug.assert(enclosingDeclaration === undefined || (enclosingDeclaration.flags & 8 /* Synthesized */) === 0);
+                    var context = createNodeBuilderContext(enclosingDeclaration, flags, tracker);
+                    var resultingNode = typeParameterToDeclaration(parameter, context);
+                    var result = context.encounteredError ? undefined : resultingNode;
+                    return result;
+                },
+            };
+            function createNodeBuilderContext(enclosingDeclaration, flags, tracker) {
+                return {
+                    enclosingDeclaration: enclosingDeclaration,
+                    flags: flags || 0 /* None */,
+                    tracker: tracker && tracker.trackSymbol ? tracker : { trackSymbol: ts.noop },
+                    encounteredError: false,
+                    visitedSymbols: undefined,
+                    inferTypeParameters: undefined
+                };
+            }
+            function typeToTypeNodeHelper(type, context) {
+                if (cancellationToken && cancellationToken.throwIfCancellationRequested) {
+                    cancellationToken.throwIfCancellationRequested();
+                }
+                var inTypeAlias = context.flags & 8388608 /* InTypeAlias */;
+                context.flags &= ~8388608 /* InTypeAlias */;
+                if (!type) {
+                    context.encounteredError = true;
+                    return undefined; // TODO: GH#18217
+                }
+                if (type.flags & 1 /* Any */) {
+                    return ts.createKeywordTypeNode(119 /* AnyKeyword */);
+                }
+                if (type.flags & 2 /* Unknown */) {
+                    return ts.createKeywordTypeNode(142 /* UnknownKeyword */);
+                }
+                if (type.flags & 4 /* String */) {
+                    return ts.createKeywordTypeNode(137 /* StringKeyword */);
+                }
+                if (type.flags & 8 /* Number */) {
+                    return ts.createKeywordTypeNode(134 /* NumberKeyword */);
+                }
+                if (type.flags & 16 /* Boolean */) {
+                    return ts.createKeywordTypeNode(122 /* BooleanKeyword */);
+                }
+                if (type.flags & 512 /* EnumLiteral */ && !(type.flags & 262144 /* Union */)) {
+                    var parentSymbol = getParentOfSymbol(type.symbol);
+                    var parentName = symbolToName(parentSymbol, context, 67901928 /* Type */, /*expectsIdentifier*/ false);
+                    var enumLiteralName = getDeclaredTypeOfSymbol(parentSymbol) === type ? parentName : ts.createQualifiedName(parentName, ts.symbolName(type.symbol));
+                    return ts.createTypeReferenceNode(enumLiteralName, /*typeArguments*/ undefined);
+                }
+                if (type.flags & 544 /* EnumLike */) {
+                    var name = symbolToName(type.symbol, context, 67901928 /* Type */, /*expectsIdentifier*/ false);
+                    return ts.createTypeReferenceNode(name, /*typeArguments*/ undefined);
+                }
+                if (type.flags & (64 /* StringLiteral */)) {
+                    return ts.createLiteralTypeNode(ts.setEmitFlags(ts.createLiteral(type.value), 16777216 /* NoAsciiEscaping */));
+                }
+                if (type.flags & (128 /* NumberLiteral */)) {
+                    return ts.createLiteralTypeNode((ts.createLiteral(type.value)));
+                }
+                if (type.flags & 256 /* BooleanLiteral */) {
+                    return type.intrinsicName === "true" ? ts.createTrue() : ts.createFalse();
+                }
+                if (type.flags & 2048 /* UniqueESSymbol */) {
+                    if (!(context.flags & 1048576 /* AllowUniqueESSymbolType */)) {
+                        if (isValueSymbolAccessible(type.symbol, context.enclosingDeclaration)) {
+                            return symbolToTypeNode(type.symbol, context, 67216319 /* Value */);
+                        }
+                        if (context.tracker.reportInaccessibleUniqueSymbolError) {
+                            context.tracker.reportInaccessibleUniqueSymbolError();
+                        }
+                    }
+                    return ts.createTypeOperatorNode(141 /* UniqueKeyword */, ts.createKeywordTypeNode(138 /* SymbolKeyword */));
+                }
+                if (type.flags & 4096 /* Void */) {
+                    return ts.createKeywordTypeNode(105 /* VoidKeyword */);
+                }
+                if (type.flags & 8192 /* Undefined */) {
+                    return ts.createKeywordTypeNode(140 /* UndefinedKeyword */);
+                }
+                if (type.flags & 16384 /* Null */) {
+                    return ts.createKeywordTypeNode(95 /* NullKeyword */);
+                }
+                if (type.flags & 32768 /* Never */) {
+                    return ts.createKeywordTypeNode(131 /* NeverKeyword */);
+                }
+                if (type.flags & 1024 /* ESSymbol */) {
+                    return ts.createKeywordTypeNode(138 /* SymbolKeyword */);
+                }
+                if (type.flags & 16777216 /* NonPrimitive */) {
+                    return ts.createKeywordTypeNode(135 /* ObjectKeyword */);
+                }
+                if (type.flags & 65536 /* TypeParameter */ && type.isThisType) {
+                    if (context.flags & 4194304 /* InObjectTypeLiteral */) {
+                        if (!context.encounteredError && !(context.flags & 32768 /* AllowThisInObjectLiteral */)) {
+                            context.encounteredError = true;
+                        }
+                        if (context.tracker.reportInaccessibleThisError) {
+                            context.tracker.reportInaccessibleThisError();
+                        }
+                    }
+                    return ts.createThis();
+                }
+                var objectFlags = ts.getObjectFlags(type);
+                if (objectFlags & 4 /* Reference */) {
+                    ts.Debug.assert(!!(type.flags & 131072 /* Object */));
+                    return typeReferenceToTypeNode(type);
+                }
+                if (type.flags & 65536 /* TypeParameter */ || objectFlags & 3 /* ClassOrInterface */) {
+                    if (type.flags & 65536 /* TypeParameter */ && ts.contains(context.inferTypeParameters, type)) {
+                        return ts.createInferTypeNode(typeParameterToDeclarationWithConstraint(type, context, /*constraintNode*/ undefined));
+                    }
+                    if (context.flags & 4 /* GenerateNamesForShadowedTypeParams */ &&
+                        type.flags & 65536 /* TypeParameter */ &&
+                        ts.length(type.symbol.declarations) &&
+                        ts.isTypeParameterDeclaration(type.symbol.declarations[0]) &&
+                        typeParameterShadowsNameInScope(type, context) &&
+                        !isTypeSymbolAccessible(type.symbol, context.enclosingDeclaration)) {
+                        return ts.createTypeReferenceNode(ts.getGeneratedNameForNode(type.symbol.declarations[0].name, 16 /* Optimistic */ | 8 /* ReservedInNestedScopes */), /*typeArguments*/ undefined);
+                    }
+                    // Ignore constraint/default when creating a usage (as opposed to declaration) of a type parameter.
+                    return type.symbol
+                        ? symbolToTypeNode(type.symbol, context, 67901928 /* Type */)
+                        : ts.createTypeReferenceNode(ts.createIdentifier("?"), /*typeArguments*/ undefined);
+                }
+                if (!inTypeAlias && type.aliasSymbol && (context.flags & 16384 /* UseAliasDefinedOutsideCurrentScope */ || isTypeSymbolAccessible(type.aliasSymbol, context.enclosingDeclaration))) {
+                    var typeArgumentNodes = mapToTypeNodes(type.aliasTypeArguments, context);
+                    if (isReservedMemberName(type.aliasSymbol.escapedName) && !(type.aliasSymbol.flags & 32 /* Class */))
+                        return ts.createTypeReferenceNode(ts.createIdentifier(""), typeArgumentNodes);
+                    return symbolToTypeNode(type.aliasSymbol, context, 67901928 /* Type */, typeArgumentNodes);
+                }
+                if (type.flags & (262144 /* Union */ | 524288 /* Intersection */)) {
+                    var types = type.flags & 262144 /* Union */ ? formatUnionTypes(type.types) : type.types;
+                    var typeNodes = mapToTypeNodes(types, context);
+                    if (typeNodes && typeNodes.length > 0) {
+                        var unionOrIntersectionTypeNode = ts.createUnionOrIntersectionTypeNode(type.flags & 262144 /* Union */ ? 169 /* UnionType */ : 170 /* IntersectionType */, typeNodes);
+                        return unionOrIntersectionTypeNode;
+                    }
+                    else {
+                        if (!context.encounteredError && !(context.flags & 262144 /* AllowEmptyUnionOrIntersection */)) {
+                            context.encounteredError = true;
+                        }
+                        return undefined; // TODO: GH#18217
+                    }
+                }
+                if (objectFlags & (16 /* Anonymous */ | 32 /* Mapped */)) {
+                    ts.Debug.assert(!!(type.flags & 131072 /* Object */));
+                    // The type is an object literal type.
+                    return createAnonymousTypeNode(type);
+                }
+                if (type.flags & 1048576 /* Index */) {
+                    var indexedType = type.type;
+                    var indexTypeNode = typeToTypeNodeHelper(indexedType, context);
+                    return ts.createTypeOperatorNode(indexTypeNode);
+                }
+                if (type.flags & 2097152 /* IndexedAccess */) {
+                    var objectTypeNode = typeToTypeNodeHelper(type.objectType, context);
+                    var indexTypeNode = typeToTypeNodeHelper(type.indexType, context);
+                    return ts.createIndexedAccessTypeNode(objectTypeNode, indexTypeNode);
+                }
+                if (type.flags & 4194304 /* Conditional */) {
+                    var checkTypeNode = typeToTypeNodeHelper(type.checkType, context);
+                    var saveInferTypeParameters = context.inferTypeParameters;
+                    context.inferTypeParameters = type.root.inferTypeParameters;
+                    var extendsTypeNode = typeToTypeNodeHelper(type.extendsType, context);
+                    context.inferTypeParameters = saveInferTypeParameters;
+                    var trueTypeNode = typeToTypeNodeHelper(getTrueTypeFromConditionalType(type), context);
+                    var falseTypeNode = typeToTypeNodeHelper(getFalseTypeFromConditionalType(type), context);
+                    return ts.createConditionalTypeNode(checkTypeNode, extendsTypeNode, trueTypeNode, falseTypeNode);
+                }
+                if (type.flags & 8388608 /* Substitution */) {
+                    return typeToTypeNodeHelper(type.typeVariable, context);
+                }
+                return ts.Debug.fail("Should be unreachable.");
+                function createMappedTypeNodeFromType(type) {
+                    ts.Debug.assert(!!(type.flags & 131072 /* Object */));
+                    var readonlyToken = type.declaration.readonlyToken ? ts.createToken(type.declaration.readonlyToken.kind) : undefined;
+                    var questionToken = type.declaration.questionToken ? ts.createToken(type.declaration.questionToken.kind) : undefined;
+                    var appropriateConstraintTypeNode;
+                    if (isMappedTypeWithKeyofConstraintDeclaration(type)) {
+                        // We have a { [P in keyof T]: X }
+                        // We do this to ensure we retain the toplevel keyof-ness of the type which may be lost due to keyof distribution during `getConstraintTypeFromMappedType`
+                        appropriateConstraintTypeNode = ts.createTypeOperatorNode(typeToTypeNodeHelper(getModifiersTypeFromMappedType(type), context));
+                    }
+                    else {
+                        appropriateConstraintTypeNode = typeToTypeNodeHelper(getConstraintTypeFromMappedType(type), context);
+                    }
+                    var typeParameterNode = typeParameterToDeclarationWithConstraint(getTypeParameterFromMappedType(type), context, appropriateConstraintTypeNode);
+                    var templateTypeNode = typeToTypeNodeHelper(getTemplateTypeFromMappedType(type), context);
+                    var mappedTypeNode = ts.createMappedTypeNode(readonlyToken, typeParameterNode, questionToken, templateTypeNode);
+                    return ts.setEmitFlags(mappedTypeNode, 1 /* SingleLine */);
+                }
+                function createAnonymousTypeNode(type) {
+                    var symbol = type.symbol;
+                    var id;
+                    if (symbol) {
+                        var isConstructorObject = ts.getObjectFlags(type) & 16 /* Anonymous */ && type.symbol && type.symbol.flags & 32 /* Class */;
+                        id = (isConstructorObject ? "+" : "") + getSymbolId(symbol);
+                        if (isJavaScriptConstructor(symbol.valueDeclaration)) {
+                            // Instance and static types share the same symbol; only add 'typeof' for the static side.
+                            var isInstanceType = type === getInferredClassType(symbol) ? 67901928 /* Type */ : 67216319 /* Value */;
+                            return symbolToTypeNode(symbol, context, isInstanceType);
+                        }
+                        // Always use 'typeof T' for type of class, enum, and module objects
+                        else if (symbol.flags & 32 /* Class */ && !getBaseTypeVariableOfClass(symbol) && !(symbol.valueDeclaration.kind === 205 /* ClassExpression */ && context.flags & 2048 /* WriteClassExpressionAsTypeLiteral */) ||
+                            symbol.flags & (384 /* Enum */ | 512 /* ValueModule */) ||
+                            shouldWriteTypeOfFunctionSymbol()) {
+                            return symbolToTypeNode(symbol, context, 67216319 /* Value */);
+                        }
+                        else if (context.visitedSymbols && context.visitedSymbols.has(id)) {
+                            // If type is an anonymous type literal in a type alias declaration, use type alias name
+                            var typeAlias = getTypeAliasForTypeLiteral(type);
+                            if (typeAlias) {
+                                // The specified symbol flags need to be reinterpreted as type flags
+                                return symbolToTypeNode(typeAlias, context, 67901928 /* Type */);
+                            }
+                            else {
+                                return ts.createKeywordTypeNode(119 /* AnyKeyword */);
+                            }
+                        }
+                        else {
+                            // Since instantiations of the same anonymous type have the same symbol, tracking symbols instead
+                            // of types allows us to catch circular references to instantiations of the same anonymous type
+                            if (!context.visitedSymbols) {
+                                context.visitedSymbols = ts.createMap();
+                            }
+                            context.visitedSymbols.set(id, true);
+                            var result = createTypeNodeFromObjectType(type);
+                            context.visitedSymbols.delete(id);
+                            return result;
+                        }
+                    }
+                    else {
+                        // Anonymous types without a symbol are never circular.
+                        return createTypeNodeFromObjectType(type);
+                    }
+                    function shouldWriteTypeOfFunctionSymbol() {
+                        var isStaticMethodSymbol = !!(symbol.flags & 8192 /* Method */) && // typeof static method
+                            ts.some(symbol.declarations, function (declaration) { return ts.hasModifier(declaration, 32 /* Static */); });
+                        var isNonLocalFunctionSymbol = !!(symbol.flags & 16 /* Function */) &&
+                            (symbol.parent || // is exported function symbol
+                                ts.forEach(symbol.declarations, function (declaration) {
+                                    return declaration.parent.kind === 274 /* SourceFile */ || declaration.parent.kind === 240 /* ModuleBlock */;
+                                }));
+                        if (isStaticMethodSymbol || isNonLocalFunctionSymbol) {
+                            // typeof is allowed only for static/non local functions
+                            return (!!(context.flags & 4096 /* UseTypeOfFunction */) || (context.visitedSymbols && context.visitedSymbols.has(id))) && // it is type of the symbol uses itself recursively
+                                (!(context.flags & 8 /* UseStructuralFallback */) || isValueSymbolAccessible(symbol, context.enclosingDeclaration)); // TODO: GH#18217 // And the build is going to succeed without visibility error or there is no structural fallback allowed
+                        }
+                    }
+                }
+                function createTypeNodeFromObjectType(type) {
+                    if (isGenericMappedType(type)) {
+                        return createMappedTypeNodeFromType(type);
+                    }
+                    var resolved = resolveStructuredTypeMembers(type);
+                    if (!resolved.properties.length && !resolved.stringIndexInfo && !resolved.numberIndexInfo) {
+                        if (!resolved.callSignatures.length && !resolved.constructSignatures.length) {
+                            return ts.setEmitFlags(ts.createTypeLiteralNode(/*members*/ undefined), 1 /* SingleLine */);
+                        }
+                        if (resolved.callSignatures.length === 1 && !resolved.constructSignatures.length) {
+                            var signature = resolved.callSignatures[0];
+                            var signatureNode = signatureToSignatureDeclarationHelper(signature, 163 /* FunctionType */, context);
+                            return signatureNode;
+                        }
+                        if (resolved.constructSignatures.length === 1 && !resolved.callSignatures.length) {
+                            var signature = resolved.constructSignatures[0];
+                            var signatureNode = signatureToSignatureDeclarationHelper(signature, 164 /* ConstructorType */, context);
+                            return signatureNode;
+                        }
+                    }
+                    var savedFlags = context.flags;
+                    context.flags |= 4194304 /* InObjectTypeLiteral */;
+                    var members = createTypeNodesFromResolvedType(resolved);
+                    context.flags = savedFlags;
+                    var typeLiteralNode = ts.createTypeLiteralNode(members);
+                    return ts.setEmitFlags(typeLiteralNode, (context.flags & 1024 /* MultilineObjectLiterals */) ? 0 : 1 /* SingleLine */);
+                }
+                function typeReferenceToTypeNode(type) {
+                    var typeArguments = type.typeArguments || ts.emptyArray;
+                    if (type.target === globalArrayType) {
+                        if (context.flags & 2 /* WriteArrayAsGenericType */) {
+                            var typeArgumentNode = typeToTypeNodeHelper(typeArguments[0], context);
+                            return ts.createTypeReferenceNode("Array", [typeArgumentNode]);
+                        }
+                        var elementType = typeToTypeNodeHelper(typeArguments[0], context);
+                        return ts.createArrayTypeNode(elementType);
+                    }
+                    else if (type.target.objectFlags & 8 /* Tuple */) {
+                        if (typeArguments.length > 0) {
+                            var tupleConstituentNodes = mapToTypeNodes(typeArguments.slice(0, getTypeReferenceArity(type)), context);
+                            if (tupleConstituentNodes && tupleConstituentNodes.length > 0) {
+                                return ts.createTupleTypeNode(tupleConstituentNodes);
+                            }
+                        }
+                        if (context.encounteredError || (context.flags & 524288 /* AllowEmptyTuple */)) {
+                            return ts.createTupleTypeNode([]);
+                        }
+                        context.encounteredError = true;
+                        return undefined; // TODO: GH#18217
+                    }
+                    else if (context.flags & 2048 /* WriteClassExpressionAsTypeLiteral */ &&
+                        type.symbol.valueDeclaration &&
+                        ts.isClassLike(type.symbol.valueDeclaration) &&
+                        !isValueSymbolAccessible(type.symbol, context.enclosingDeclaration)) {
+                        return createAnonymousTypeNode(type);
+                    }
+                    else {
+                        var outerTypeParameters = type.target.outerTypeParameters;
+                        var i = 0;
+                        var resultType = void 0;
+                        if (outerTypeParameters) {
+                            var length_1 = outerTypeParameters.length;
+                            while (i < length_1) {
+                                // Find group of type arguments for type parameters with the same declaring container.
+                                var start = i;
+                                var parent = getParentSymbolOfTypeParameter(outerTypeParameters[i]);
+                                do {
+                                    i++;
+                                } while (i < length_1 && getParentSymbolOfTypeParameter(outerTypeParameters[i]) === parent);
+                                // When type parameters are their own type arguments for the whole group (i.e. we have
+                                // the default outer type arguments), we don't show the group.
+                                if (!ts.rangeEquals(outerTypeParameters, typeArguments, start, i)) {
+                                    var typeArgumentSlice = mapToTypeNodes(typeArguments.slice(start, i), context);
+                                    var flags_2 = context.flags;
+                                    context.flags |= 16 /* ForbidIndexedAccessSymbolReferences */;
+                                    var ref = symbolToTypeNode(parent, context, 67901928 /* Type */, typeArgumentSlice);
+                                    context.flags = flags_2;
+                                    resultType = !resultType ? ref : appendReferenceToType(resultType, ref);
+                                }
+                            }
+                        }
+                        var typeArgumentNodes = void 0;
+                        if (typeArguments.length > 0) {
+                            var typeParameterCount = (type.target.typeParameters || ts.emptyArray).length;
+                            typeArgumentNodes = mapToTypeNodes(typeArguments.slice(i, typeParameterCount), context);
+                        }
+                        var flags = context.flags;
+                        context.flags |= 16 /* ForbidIndexedAccessSymbolReferences */;
+                        var finalRef = symbolToTypeNode(type.symbol, context, 67901928 /* Type */, typeArgumentNodes);
+                        context.flags = flags;
+                        return !resultType ? finalRef : appendReferenceToType(resultType, finalRef);
+                    }
+                }
+                function appendReferenceToType(root, ref) {
+                    if (ts.isImportTypeNode(root)) {
+                        // first shift type arguments
+                        var innerParams = root.typeArguments;
+                        if (root.qualifier) {
+                            (ts.isIdentifier(root.qualifier) ? root.qualifier : root.qualifier.right).typeArguments = innerParams;
+                        }
+                        root.typeArguments = ref.typeArguments;
+                        // then move qualifiers
+                        var ids = getAccessStack(ref);
+                        for (var _i = 0, ids_1 = ids; _i < ids_1.length; _i++) {
+                            var id = ids_1[_i];
+                            root.qualifier = root.qualifier ? ts.createQualifiedName(root.qualifier, id) : id;
+                        }
+                        return root;
+                    }
+                    else {
+                        // first shift type arguments
+                        var innerParams = root.typeArguments;
+                        (ts.isIdentifier(root.typeName) ? root.typeName : root.typeName.right).typeArguments = innerParams;
+                        root.typeArguments = ref.typeArguments;
+                        // then move qualifiers
+                        var ids = getAccessStack(ref);
+                        for (var _a = 0, ids_2 = ids; _a < ids_2.length; _a++) {
+                            var id = ids_2[_a];
+                            root.typeName = ts.createQualifiedName(root.typeName, id);
+                        }
+                        return root;
+                    }
+                }
+                function getAccessStack(ref) {
+                    var state = ref.typeName;
+                    var ids = [];
+                    while (!ts.isIdentifier(state)) {
+                        ids.unshift(state.right);
+                        state = state.left;
+                    }
+                    ids.unshift(state);
+                    return ids;
+                }
+                function createTypeNodesFromResolvedType(resolvedType) {
+                    var typeElements = [];
+                    for (var _i = 0, _a = resolvedType.callSignatures; _i < _a.length; _i++) {
+                        var signature = _a[_i];
+                        typeElements.push(signatureToSignatureDeclarationHelper(signature, 158 /* CallSignature */, context));
+                    }
+                    for (var _b = 0, _c = resolvedType.constructSignatures; _b < _c.length; _b++) {
+                        var signature = _c[_b];
+                        typeElements.push(signatureToSignatureDeclarationHelper(signature, 159 /* ConstructSignature */, context));
+                    }
+                    if (resolvedType.stringIndexInfo) {
+                        var indexInfo = resolvedType.objectFlags & 2048 /* ReverseMapped */ ?
+                            createIndexInfo(anyType, resolvedType.stringIndexInfo.isReadonly, resolvedType.stringIndexInfo.declaration) :
+                            resolvedType.stringIndexInfo;
+                        typeElements.push(indexInfoToIndexSignatureDeclarationHelper(indexInfo, 0 /* String */, context));
+                    }
+                    if (resolvedType.numberIndexInfo) {
+                        typeElements.push(indexInfoToIndexSignatureDeclarationHelper(resolvedType.numberIndexInfo, 1 /* Number */, context));
+                    }
+                    var properties = resolvedType.properties;
+                    if (!properties) {
+                        return typeElements;
+                    }
+                    for (var _d = 0, properties_1 = properties; _d < properties_1.length; _d++) {
+                        var propertySymbol = properties_1[_d];
+                        if (context.flags & 2048 /* WriteClassExpressionAsTypeLiteral */) {
+                            if (propertySymbol.flags & 4194304 /* Prototype */) {
+                                continue;
+                            }
+                            if (ts.getDeclarationModifierFlagsFromSymbol(propertySymbol) & (8 /* Private */ | 16 /* Protected */) && context.tracker.reportPrivateInBaseOfClassExpression) {
+                                context.tracker.reportPrivateInBaseOfClassExpression(ts.unescapeLeadingUnderscores(propertySymbol.escapedName));
+                            }
+                        }
+                        var propertyType = ts.getCheckFlags(propertySymbol) & 2048 /* ReverseMapped */ && context.flags & 33554432 /* InReverseMappedType */ ?
+                            anyType : getTypeOfSymbol(propertySymbol);
+                        var saveEnclosingDeclaration = context.enclosingDeclaration;
+                        context.enclosingDeclaration = undefined;
+                        if (ts.getCheckFlags(propertySymbol) & 1024 /* Late */) {
+                            var decl = ts.first(propertySymbol.declarations);
+                            if (context.tracker.trackSymbol && hasLateBindableName(decl)) {
+                                // get symbol of the first identifier of the entityName
+                                var firstIdentifier = getFirstIdentifier(decl.name.expression);
+                                var name = resolveName(firstIdentifier, firstIdentifier.escapedText, 67216319 /* Value */ | 1048576 /* ExportValue */, /*nodeNotFoundErrorMessage*/ undefined, /*nameArg*/ undefined, /*isUse*/ true);
+                                if (name) {
+                                    context.tracker.trackSymbol(name, saveEnclosingDeclaration, 67216319 /* Value */);
+                                }
+                            }
+                        }
+                        var propertyName = symbolToName(propertySymbol, context, 67216319 /* Value */, /*expectsIdentifier*/ true);
+                        context.enclosingDeclaration = saveEnclosingDeclaration;
+                        var optionalToken = propertySymbol.flags & 16777216 /* Optional */ ? ts.createToken(55 /* QuestionToken */) : undefined;
+                        if (propertySymbol.flags & (16 /* Function */ | 8192 /* Method */) && !getPropertiesOfObjectType(propertyType).length) {
+                            var signatures = getSignaturesOfType(propertyType, 0 /* Call */);
+                            for (var _e = 0, signatures_1 = signatures; _e < signatures_1.length; _e++) {
+                                var signature = signatures_1[_e];
+                                var methodDeclaration = signatureToSignatureDeclarationHelper(signature, 153 /* MethodSignature */, context);
+                                methodDeclaration.name = propertyName;
+                                methodDeclaration.questionToken = optionalToken;
+                                if (propertySymbol.valueDeclaration) {
+                                    // Copy comments to node for declaration emit
+                                    ts.setCommentRange(methodDeclaration, propertySymbol.valueDeclaration);
+                                }
+                                typeElements.push(methodDeclaration);
+                            }
+                        }
+                        else {
+                            var savedFlags = context.flags;
+                            context.flags |= !!(ts.getCheckFlags(propertySymbol) & 2048 /* ReverseMapped */) ? 33554432 /* InReverseMappedType */ : 0;
+                            var propertyTypeNode = propertyType ? typeToTypeNodeHelper(propertyType, context) : ts.createKeywordTypeNode(119 /* AnyKeyword */);
+                            context.flags = savedFlags;
+                            var modifiers = isReadonlySymbol(propertySymbol) ? [ts.createToken(132 /* ReadonlyKeyword */)] : undefined;
+                            var propertySignature = ts.createPropertySignature(modifiers, propertyName, optionalToken, propertyTypeNode, 
+                            /*initializer*/ undefined);
+                            if (propertySymbol.valueDeclaration) {
+                                // Copy comments to node for declaration emit
+                                ts.setCommentRange(propertySignature, propertySymbol.valueDeclaration);
+                            }
+                            typeElements.push(propertySignature);
+                        }
+                    }
+                    return typeElements.length ? typeElements : undefined;
+                }
+            }
+            function mapToTypeNodes(types, context) {
+                if (ts.some(types)) {
+                    var result = [];
+                    for (var _i = 0, types_1 = types; _i < types_1.length; _i++) {
+                        var type = types_1[_i];
+                        var typeNode = typeToTypeNodeHelper(type, context);
+                        if (typeNode) {
+                            result.push(typeNode);
+                        }
+                    }
+                    return result;
+                }
+            }
+            function indexInfoToIndexSignatureDeclarationHelper(indexInfo, kind, context) {
+                var name = ts.getNameFromIndexInfo(indexInfo) || "x";
+                var indexerTypeNode = ts.createKeywordTypeNode(kind === 0 /* String */ ? 137 /* StringKeyword */ : 134 /* NumberKeyword */);
+                var indexingParameter = ts.createParameter(
+                /*decorators*/ undefined, 
+                /*modifiers*/ undefined, 
+                /*dotDotDotToken*/ undefined, name, 
+                /*questionToken*/ undefined, indexerTypeNode, 
+                /*initializer*/ undefined);
+                var typeNode = typeToTypeNodeHelper(indexInfo.type || anyType, context);
+                if (!indexInfo.type && !(context.flags & 2097152 /* AllowEmptyIndexInfoType */)) {
+                    context.encounteredError = true;
+                }
+                return ts.createIndexSignature(
+                /*decorators*/ undefined, indexInfo.isReadonly ? [ts.createToken(132 /* ReadonlyKeyword */)] : undefined, [indexingParameter], typeNode);
+            }
+            function signatureToSignatureDeclarationHelper(signature, kind, context) {
+                var typeParameters;
+                var typeArguments;
+                if (context.flags & 32 /* WriteTypeArgumentsOfSignature */ && signature.target && signature.mapper && signature.target.typeParameters) {
+                    typeArguments = signature.target.typeParameters.map(function (parameter) { return typeToTypeNodeHelper(instantiateType(parameter, signature.mapper), context); });
+                }
+                else {
+                    typeParameters = signature.typeParameters && signature.typeParameters.map(function (parameter) { return typeParameterToDeclaration(parameter, context); });
+                }
+                var parameters = signature.parameters.map(function (parameter) { return symbolToParameterDeclaration(parameter, context, kind === 155 /* Constructor */); });
+                if (signature.thisParameter) {
+                    var thisParameter = symbolToParameterDeclaration(signature.thisParameter, context);
+                    parameters.unshift(thisParameter);
+                }
+                var returnTypeNode;
+                var typePredicate = getTypePredicateOfSignature(signature);
+                if (typePredicate) {
+                    var parameterName = typePredicate.kind === 1 /* Identifier */ ?
+                        ts.setEmitFlags(ts.createIdentifier(typePredicate.parameterName), 16777216 /* NoAsciiEscaping */) :
+                        ts.createThisTypeNode();
+                    var typeNode = typeToTypeNodeHelper(typePredicate.type, context);
+                    returnTypeNode = ts.createTypePredicateNode(parameterName, typeNode);
+                }
+                else {
+                    var returnType = getReturnTypeOfSignature(signature);
+                    returnTypeNode = returnType && typeToTypeNodeHelper(returnType, context);
+                }
+                if (context.flags & 256 /* SuppressAnyReturnType */) {
+                    if (returnTypeNode && returnTypeNode.kind === 119 /* AnyKeyword */) {
+                        returnTypeNode = undefined;
+                    }
+                }
+                else if (!returnTypeNode) {
+                    returnTypeNode = ts.createKeywordTypeNode(119 /* AnyKeyword */);
+                }
+                return ts.createSignatureDeclaration(kind, typeParameters, parameters, returnTypeNode, typeArguments);
+            }
+            function typeParameterShadowsNameInScope(type, context) {
+                return !!resolveName(context.enclosingDeclaration, type.symbol.escapedName, 67901928 /* Type */, /*nameNotFoundArg*/ undefined, type.symbol.escapedName, /*isUse*/ false);
+            }
+            function typeParameterToDeclarationWithConstraint(type, context, constraintNode) {
+                var savedContextFlags = context.flags;
+                context.flags &= ~512 /* WriteTypeParametersInQualifiedName */; // Avoids potential infinite loop when building for a claimspace with a generic
+                var shouldUseGeneratedName = context.flags & 4 /* GenerateNamesForShadowedTypeParams */ &&
+                    type.symbol.declarations[0] &&
+                    ts.isTypeParameterDeclaration(type.symbol.declarations[0]) &&
+                    typeParameterShadowsNameInScope(type, context);
+                var name = shouldUseGeneratedName
+                    ? ts.getGeneratedNameForNode(type.symbol.declarations[0].name, 16 /* Optimistic */ | 8 /* ReservedInNestedScopes */)
+                    : symbolToName(type.symbol, context, 67901928 /* Type */, /*expectsIdentifier*/ true);
+                var defaultParameter = getDefaultFromTypeParameter(type);
+                var defaultParameterNode = defaultParameter && typeToTypeNodeHelper(defaultParameter, context);
+                context.flags = savedContextFlags;
+                return ts.createTypeParameterDeclaration(name, constraintNode, defaultParameterNode);
+            }
+            function typeParameterToDeclaration(type, context, constraint) {
+                if (constraint === void 0) { constraint = getConstraintFromTypeParameter(type); }
+                var constraintNode = constraint && typeToTypeNodeHelper(constraint, context);
+                return typeParameterToDeclarationWithConstraint(type, context, constraintNode);
+            }
+            function symbolToParameterDeclaration(parameterSymbol, context, preserveModifierFlags) {
+                var parameterDeclaration = ts.getDeclarationOfKind(parameterSymbol, 149 /* Parameter */);
+                if (!parameterDeclaration && !isTransientSymbol(parameterSymbol)) {
+                    parameterDeclaration = ts.getDeclarationOfKind(parameterSymbol, 293 /* JSDocParameterTag */);
+                }
+                var parameterType = getTypeOfSymbol(parameterSymbol);
+                if (parameterDeclaration && isRequiredInitializedParameter(parameterDeclaration)) {
+                    parameterType = getOptionalType(parameterType);
+                }
+                var parameterTypeNode = typeToTypeNodeHelper(parameterType, context);
+                var modifiers = !(context.flags & 8192 /* OmitParameterModifiers */) && preserveModifierFlags && parameterDeclaration && parameterDeclaration.modifiers ? parameterDeclaration.modifiers.map(ts.getSynthesizedClone) : undefined;
+                var isRest = parameterDeclaration ? ts.isRestParameter(parameterDeclaration) : parameterSymbol.isRestParameter;
+                var dotDotDotToken = isRest ? ts.createToken(24 /* DotDotDotToken */) : undefined;
+                var name = parameterDeclaration
+                    ? parameterDeclaration.name ?
+                        parameterDeclaration.name.kind === 71 /* Identifier */ ? ts.setEmitFlags(ts.getSynthesizedClone(parameterDeclaration.name), 16777216 /* NoAsciiEscaping */) :
+                            parameterDeclaration.name.kind === 146 /* QualifiedName */ ? ts.setEmitFlags(ts.getSynthesizedClone(parameterDeclaration.name.right), 16777216 /* NoAsciiEscaping */) :
+                                cloneBindingName(parameterDeclaration.name) :
+                        ts.symbolName(parameterSymbol)
+                    : ts.symbolName(parameterSymbol);
+                var questionToken = parameterDeclaration && isOptionalParameter(parameterDeclaration) ? ts.createToken(55 /* QuestionToken */) : undefined;
+                var parameterNode = ts.createParameter(
+                /*decorators*/ undefined, modifiers, dotDotDotToken, name, questionToken, parameterTypeNode, 
+                /*initializer*/ undefined);
+                return parameterNode;
+                function cloneBindingName(node) {
+                    return elideInitializerAndSetEmitFlags(node);
+                    function elideInitializerAndSetEmitFlags(node) {
+                        var visited = ts.visitEachChild(node, elideInitializerAndSetEmitFlags, ts.nullTransformationContext, /*nodesVisitor*/ undefined, elideInitializerAndSetEmitFlags);
+                        var clone = ts.nodeIsSynthesized(visited) ? visited : ts.getSynthesizedClone(visited);
+                        if (clone.kind === 182 /* BindingElement */) {
+                            clone.initializer = undefined;
+                        }
+                        return ts.setEmitFlags(clone, 1 /* SingleLine */ | 16777216 /* NoAsciiEscaping */);
+                    }
+                }
+            }
+            function lookupSymbolChain(symbol, context, meaning, yieldModuleSymbol) {
+                context.tracker.trackSymbol(symbol, context.enclosingDeclaration, meaning); // TODO: GH#18217
+                // Try to get qualified name if the symbol is not a type parameter and there is an enclosing declaration.
+                var chain;
+                var isTypeParameter = symbol.flags & 262144 /* TypeParameter */;
+                if (!isTypeParameter && (context.enclosingDeclaration || context.flags & 64 /* UseFullyQualifiedType */)) {
+                    chain = ts.Debug.assertDefined(getSymbolChain(symbol, meaning, /*endOfChain*/ true));
+                    ts.Debug.assert(chain && chain.length > 0);
+                }
+                else {
+                    chain = [symbol];
+                }
+                return chain;
+                /** @param endOfChain Set to false for recursive calls; non-recursive calls should always output something. */
+                function getSymbolChain(symbol, meaning, endOfChain) {
+                    var accessibleSymbolChain = getAccessibleSymbolChain(symbol, context.enclosingDeclaration, meaning, !!(context.flags & 128 /* UseOnlyExternalAliasing */));
+                    var parentSymbol;
+                    if (!accessibleSymbolChain ||
+                        needsQualification(accessibleSymbolChain[0], context.enclosingDeclaration, accessibleSymbolChain.length === 1 ? meaning : getQualifiedLeftMeaning(meaning))) {
+                        // Go up and add our parent.
+                        var parent = getContainerOfSymbol(accessibleSymbolChain ? accessibleSymbolChain[0] : symbol);
+                        if (parent) {
+                            var parentChain = getSymbolChain(parent, getQualifiedLeftMeaning(meaning), /*endOfChain*/ false);
+                            if (parentChain) {
+                                parentSymbol = parent;
+                                accessibleSymbolChain = parentChain.concat(accessibleSymbolChain || [getAliasForSymbolInContainer(parent, symbol) || symbol]);
+                            }
+                        }
+                    }
+                    if (accessibleSymbolChain) {
+                        return accessibleSymbolChain;
+                    }
+                    if (
+                    // If this is the last part of outputting the symbol, always output. The cases apply only to parent symbols.
+                    endOfChain ||
+                        // If a parent symbol is an external module, don't write it. (We prefer just `x` vs `"foo/bar".x`.)
+                        (yieldModuleSymbol || !(!parentSymbol && ts.forEach(symbol.declarations, hasNonGlobalAugmentationExternalModuleSymbol))) &&
+                            // If a parent symbol is an anonymous type, don't write it.
+                            !(symbol.flags & (2048 /* TypeLiteral */ | 4096 /* ObjectLiteral */))) {
+                        return [symbol];
+                    }
+                }
+            }
+            function typeParametersToTypeParameterDeclarations(symbol, context) {
+                var typeParameterNodes;
+                var targetSymbol = getTargetSymbol(symbol);
+                if (targetSymbol.flags & (32 /* Class */ | 64 /* Interface */ | 524288 /* TypeAlias */)) {
+                    typeParameterNodes = ts.createNodeArray(ts.map(getLocalTypeParametersOfClassOrInterfaceOrTypeAlias(symbol), function (tp) { return typeParameterToDeclaration(tp, context); }));
+                }
+                return typeParameterNodes;
+            }
+            function lookupTypeParameterNodes(chain, index, context) {
+                ts.Debug.assert(chain && 0 <= index && index < chain.length);
+                var symbol = chain[index];
+                var typeParameterNodes;
+                if (context.flags & 512 /* WriteTypeParametersInQualifiedName */ && index < (chain.length - 1)) {
+                    var parentSymbol = symbol;
+                    var nextSymbol = chain[index + 1];
+                    if (ts.getCheckFlags(nextSymbol) & 1 /* Instantiated */) {
+                        var params = getTypeParametersOfClassOrInterface(parentSymbol.flags & 2097152 /* Alias */ ? resolveAlias(parentSymbol) : parentSymbol);
+                        typeParameterNodes = mapToTypeNodes(ts.map(params, nextSymbol.mapper), context);
+                    }
+                    else {
+                        typeParameterNodes = typeParametersToTypeParameterDeclarations(symbol, context);
+                    }
+                }
+                return typeParameterNodes;
+            }
+            /**
+             * Given A[B][C][D], finds A[B]
+             */
+            function getTopmostIndexedAccessType(top) {
+                if (ts.isIndexedAccessTypeNode(top.objectType)) {
+                    return getTopmostIndexedAccessType(top.objectType);
+                }
+                return top;
+            }
+            function symbolToTypeNode(symbol, context, meaning, overrideTypeArguments) {
+                var chain = lookupSymbolChain(symbol, context, meaning, !(context.flags & 16384 /* UseAliasDefinedOutsideCurrentScope */)); // If we're using aliases outside the current scope, dont bother with the module
+                context.flags |= 16777216 /* InInitialEntityName */;
+                var rootName = getNameOfSymbolAsWritten(chain[0], context);
+                context.flags ^= 16777216 /* InInitialEntityName */;
+                var isTypeOf = meaning === 67216319 /* Value */;
+                if (ambientModuleSymbolRegex.test(rootName)) {
+                    // module is root, must use `ImportTypeNode`
+                    var nonRootParts = chain.length > 1 ? createAccessFromSymbolChain(chain, chain.length - 1, 1) : undefined;
+                    var typeParameterNodes = overrideTypeArguments || lookupTypeParameterNodes(chain, 0, context);
+                    var lit = ts.createLiteralTypeNode(ts.createLiteral(rootName.substring(1, rootName.length - 1)));
+                    if (!nonRootParts || ts.isEntityName(nonRootParts)) {
+                        if (nonRootParts) {
+                            var lastId = ts.isIdentifier(nonRootParts) ? nonRootParts : nonRootParts.right;
+                            lastId.typeArguments = undefined;
+                        }
+                        return ts.createImportTypeNode(lit, nonRootParts, typeParameterNodes, isTypeOf);
+                    }
+                    else {
+                        var splitNode = getTopmostIndexedAccessType(nonRootParts);
+                        var qualifier = splitNode.objectType.typeName;
+                        return ts.createIndexedAccessTypeNode(ts.createImportTypeNode(lit, qualifier, typeParameterNodes, isTypeOf), splitNode.indexType);
+                    }
+                }
+                var entityName = createAccessFromSymbolChain(chain, chain.length - 1, 0);
+                if (ts.isIndexedAccessTypeNode(entityName)) {
+                    return entityName; // Indexed accesses can never be `typeof`
+                }
+                if (isTypeOf) {
+                    return ts.createTypeQueryNode(entityName);
+                }
+                else {
+                    var lastId = ts.isIdentifier(entityName) ? entityName : entityName.right;
+                    var lastTypeArgs = lastId.typeArguments;
+                    lastId.typeArguments = undefined;
+                    return ts.createTypeReferenceNode(entityName, lastTypeArgs);
+                }
+                function createAccessFromSymbolChain(chain, index, stopper) {
+                    var typeParameterNodes = index === (chain.length - 1) ? overrideTypeArguments : lookupTypeParameterNodes(chain, index, context);
+                    var symbol = chain[index];
+                    if (index === 0) {
+                        context.flags |= 16777216 /* InInitialEntityName */;
+                    }
+                    var symbolName = getNameOfSymbolAsWritten(symbol, context);
+                    if (index === 0) {
+                        context.flags ^= 16777216 /* InInitialEntityName */;
+                    }
+                    var parent = chain[index - 1];
+                    if (!(context.flags & 16 /* ForbidIndexedAccessSymbolReferences */) && parent && getMembersOfSymbol(parent) && getMembersOfSymbol(parent).get(symbol.escapedName) === symbol) {
+                        // Should use an indexed access
+                        var LHS = createAccessFromSymbolChain(chain, index - 1, stopper);
+                        if (ts.isIndexedAccessTypeNode(LHS)) {
+                            return ts.createIndexedAccessTypeNode(LHS, ts.createLiteralTypeNode(ts.createLiteral(symbolName)));
+                        }
+                        else {
+                            return ts.createIndexedAccessTypeNode(ts.createTypeReferenceNode(LHS, typeParameterNodes), ts.createLiteralTypeNode(ts.createLiteral(symbolName)));
+                        }
+                    }
+                    var identifier = ts.setEmitFlags(ts.createIdentifier(symbolName, typeParameterNodes), 16777216 /* NoAsciiEscaping */);
+                    identifier.symbol = symbol;
+                    if (index > stopper) {
+                        var LHS = createAccessFromSymbolChain(chain, index - 1, stopper);
+                        if (!ts.isEntityName(LHS)) {
+                            return ts.Debug.fail("Impossible construct - an export of an indexed access cannot be reachable");
+                        }
+                        return ts.createQualifiedName(LHS, identifier);
+                    }
+                    return identifier;
+                }
+            }
+            function symbolToName(symbol, context, meaning, expectsIdentifier) {
+                var chain = lookupSymbolChain(symbol, context, meaning);
+                if (expectsIdentifier && chain.length !== 1
+                    && !context.encounteredError
+                    && !(context.flags & 65536 /* AllowQualifedNameInPlaceOfIdentifier */)) {
+                    context.encounteredError = true;
+                }
+                return createEntityNameFromSymbolChain(chain, chain.length - 1);
+                function createEntityNameFromSymbolChain(chain, index) {
+                    var typeParameterNodes = lookupTypeParameterNodes(chain, index, context);
+                    var symbol = chain[index];
+                    if (index === 0) {
+                        context.flags |= 16777216 /* InInitialEntityName */;
+                    }
+                    var symbolName = getNameOfSymbolAsWritten(symbol, context);
+                    if (index === 0) {
+                        context.flags ^= 16777216 /* InInitialEntityName */;
+                    }
+                    var identifier = ts.setEmitFlags(ts.createIdentifier(symbolName, typeParameterNodes), 16777216 /* NoAsciiEscaping */);
+                    identifier.symbol = symbol;
+                    return index > 0 ? ts.createQualifiedName(createEntityNameFromSymbolChain(chain, index - 1), identifier) : identifier;
+                }
+            }
+            function symbolToExpression(symbol, context, meaning) {
+                var chain = lookupSymbolChain(symbol, context, meaning);
+                return createExpressionFromSymbolChain(chain, chain.length - 1);
+                function createExpressionFromSymbolChain(chain, index) {
+                    var typeParameterNodes = lookupTypeParameterNodes(chain, index, context);
+                    var symbol = chain[index];
+                    if (index === 0) {
+                        context.flags |= 16777216 /* InInitialEntityName */;
+                    }
+                    var symbolName = getNameOfSymbolAsWritten(symbol, context);
+                    if (index === 0) {
+                        context.flags ^= 16777216 /* InInitialEntityName */;
+                    }
+                    var firstChar = symbolName.charCodeAt(0);
+                    var canUsePropertyAccess = ts.isIdentifierStart(firstChar, languageVersion);
+                    if (index === 0 || canUsePropertyAccess) {
+                        var identifier = ts.setEmitFlags(ts.createIdentifier(symbolName, typeParameterNodes), 16777216 /* NoAsciiEscaping */);
+                        identifier.symbol = symbol;
+                        return index > 0 ? ts.createPropertyAccess(createExpressionFromSymbolChain(chain, index - 1), identifier) : identifier;
+                    }
+                    else {
+                        if (firstChar === 91 /* openBracket */) {
+                            symbolName = symbolName.substring(1, symbolName.length - 1);
+                            firstChar = symbolName.charCodeAt(0);
+                        }
+                        var expression = void 0;
+                        if (ts.isSingleOrDoubleQuote(firstChar)) {
+                            expression = ts.createLiteral(symbolName.substring(1, symbolName.length - 1).replace(/\\./g, function (s) { return s.substring(1); }));
+                            expression.singleQuote = firstChar === 39 /* singleQuote */;
+                        }
+                        else if (("" + +symbolName) === symbolName) {
+                            expression = ts.createLiteral(+symbolName);
+                        }
+                        if (!expression) {
+                            expression = ts.setEmitFlags(ts.createIdentifier(symbolName, typeParameterNodes), 16777216 /* NoAsciiEscaping */);
+                            expression.symbol = symbol;
+                        }
+                        return ts.createElementAccess(createExpressionFromSymbolChain(chain, index - 1), expression);
+                    }
+                }
+            }
+        }
+        function typePredicateToString(typePredicate, enclosingDeclaration, flags, writer) {
+            if (flags === void 0) { flags = 16384 /* UseAliasDefinedOutsideCurrentScope */; }
+            return writer ? typePredicateToStringWorker(writer).getText() : ts.usingSingleLineStringWriter(typePredicateToStringWorker);
+            function typePredicateToStringWorker(writer) {
+                var predicate = ts.createTypePredicateNode(typePredicate.kind === 1 /* Identifier */ ? ts.createIdentifier(typePredicate.parameterName) : ts.createThisTypeNode(), nodeBuilder.typeToTypeNode(typePredicate.type, enclosingDeclaration, toNodeBuilderFlags(flags) | 3112960 /* IgnoreErrors */ | 512 /* WriteTypeParametersInQualifiedName */));
+                var printer = ts.createPrinter({ removeComments: true });
+                var sourceFile = enclosingDeclaration && ts.getSourceFileOfNode(enclosingDeclaration);
+                printer.writeNode(4 /* Unspecified */, predicate, /*sourceFile*/ sourceFile, writer);
+                return writer;
+            }
+        }
+        function formatUnionTypes(types) {
+            var result = [];
+            var flags = 0;
+            for (var i = 0; i < types.length; i++) {
+                var t = types[i];
+                flags |= t.flags;
+                if (!(t.flags & 24576 /* Nullable */)) {
+                    if (t.flags & (256 /* BooleanLiteral */ | 512 /* EnumLiteral */)) {
+                        var baseType = t.flags & 256 /* BooleanLiteral */ ? booleanType : getBaseTypeOfEnumLiteralType(t);
+                        if (baseType.flags & 262144 /* Union */) {
+                            var count = baseType.types.length;
+                            if (i + count <= types.length && types[i + count - 1] === baseType.types[count - 1]) {
+                                result.push(baseType);
+                                i += count - 1;
+                                continue;
+                            }
+                        }
+                    }
+                    result.push(t);
+                }
+            }
+            if (flags & 16384 /* Null */)
+                result.push(nullType);
+            if (flags & 8192 /* Undefined */)
+                result.push(undefinedType);
+            return result || types;
+        }
+        function visibilityToString(flags) {
+            if (flags === 8 /* Private */) {
+                return "private";
+            }
+            if (flags === 16 /* Protected */) {
+                return "protected";
+            }
+            return "public";
+        }
+        function getTypeAliasForTypeLiteral(type) {
+            if (type.symbol && type.symbol.flags & 2048 /* TypeLiteral */) {
+                var node = ts.findAncestor(type.symbol.declarations[0].parent, function (n) { return n.kind !== 173 /* ParenthesizedType */; });
+                if (node.kind === 237 /* TypeAliasDeclaration */) {
+                    return getSymbolOfNode(node);
+                }
+            }
+            return undefined;
+        }
+        function isTopLevelInExternalModuleAugmentation(node) {
+            return node && node.parent &&
+                node.parent.kind === 240 /* ModuleBlock */ &&
+                ts.isExternalModuleAugmentation(node.parent.parent);
+        }
+        function isDefaultBindingContext(location) {
+            return location.kind === 274 /* SourceFile */ || ts.isAmbientModule(location);
+        }
+        /**
+         * Gets a human-readable name for a symbol.
+         * Should *not* be used for the right-hand side of a `.` -- use `symbolName(symbol)` for that instead.
+         *
+         * Unlike `symbolName(symbol)`, this will include quotes if the name is from a string literal.
+         * It will also use a representation of a number as written instead of a decimal form, e.g. `0o11` instead of `9`.
+         */
+        function getNameOfSymbolAsWritten(symbol, context) {
+            if (context && symbol.escapedName === "default" /* Default */ && !(context.flags & 16384 /* UseAliasDefinedOutsideCurrentScope */) &&
+                // If it's not the first part of an entity name, it must print as `default`
+                (!(context.flags & 16777216 /* InInitialEntityName */) ||
+                    // if the symbol is synthesized, it will only be referenced externally it must print as `default`
+                    !symbol.declarations ||
+                    // if not in the same binding context (source file, module declaration), it must print as `default`
+                    (context.enclosingDeclaration && ts.findAncestor(symbol.declarations[0], isDefaultBindingContext) !== ts.findAncestor(context.enclosingDeclaration, isDefaultBindingContext)))) {
+                return "default";
+            }
+            if (symbol.declarations && symbol.declarations.length) {
+                if (ts.some(symbol.declarations, hasExternalModuleSymbol) && context.enclosingDeclaration) { // TODO: GH#18217
+                    var file = ts.getDeclarationOfKind(symbol, 274 /* SourceFile */);
+                    if (!file || !context.tracker.moduleResolverHost) {
+                        if (context.tracker.trackReferencedAmbientModule) {
+                            var ambientDecls = ts.filter(symbol.declarations, ts.isAmbientModule);
+                            if (ts.length(ambientDecls)) {
+                                for (var _i = 0, ambientDecls_1 = ambientDecls; _i < ambientDecls_1.length; _i++) {
+                                    var decl = ambientDecls_1[_i];
+                                    context.tracker.trackReferencedAmbientModule(decl); // TODO: GH#18217
+                                }
+                            }
+                        }
+                        // ambient module, just use declaration/symbol name (fallthrough)
+                    }
+                    else {
+                        var contextFile = ts.getSourceFileOfNode(ts.getOriginalNode(context.enclosingDeclaration));
+                        return "\"" + (file.moduleName || ts.moduleSpecifiers.getModuleSpecifier(compilerOptions, contextFile, contextFile.path, file.path, context.tracker.moduleResolverHost)) + "\"";
+                    }
+                }
+                var declaration = symbol.declarations[0];
+                var name = ts.getNameOfDeclaration(declaration);
+                if (name) {
+                    return ts.declarationNameToString(name);
+                }
+                if (declaration.parent && declaration.parent.kind === 232 /* VariableDeclaration */) {
+                    return ts.declarationNameToString(declaration.parent.name);
+                }
+                if (context && !context.encounteredError && !(context.flags & 131072 /* AllowAnonymousIdentifier */)) {
+                    context.encounteredError = true;
+                }
+                switch (declaration.kind) {
+                    case 205 /* ClassExpression */:
+                        return "(Anonymous class)";
+                    case 192 /* FunctionExpression */:
+                    case 193 /* ArrowFunction */:
+                        return "(Anonymous function)";
+                }
+            }
+            var nameType = symbol.nameType;
+            if (nameType) {
+                if (nameType.flags & 64 /* StringLiteral */ && !ts.isIdentifierText(nameType.value, compilerOptions.target)) {
+                    return "\"" + ts.escapeString(nameType.value, 34 /* doubleQuote */) + "\"";
+                }
+                if (nameType && nameType.flags & 2048 /* UniqueESSymbol */) {
+                    return "[" + getNameOfSymbolAsWritten(nameType.symbol, context) + "]";
+                }
+            }
+            return ts.symbolName(symbol);
+        }
+        function isDeclarationVisible(node) {
+            if (node) {
+                var links = getNodeLinks(node);
+                if (links.isVisible === undefined) {
+                    links.isVisible = !!determineIfDeclarationIsVisible();
+                }
+                return links.isVisible;
+            }
+            return false;
+            function determineIfDeclarationIsVisible() {
+                switch (node.kind) {
+                    case 292 /* JSDocCallbackTag */:
+                    case 297 /* JSDocTypedefTag */:
+                        // Top-level jsdoc type aliases are considered exported
+                        // First parent is comment node, second is hosting declaration or token; we only care about those tokens or declarations whose parent is a source file
+                        return !!(node.parent && node.parent.parent && node.parent.parent.parent && ts.isSourceFile(node.parent.parent.parent));
+                    case 182 /* BindingElement */:
+                        return isDeclarationVisible(node.parent.parent);
+                    case 232 /* VariableDeclaration */:
+                        if (ts.isBindingPattern(node.name) &&
+                            !node.name.elements.length) {
+                            // If the binding pattern is empty, this variable declaration is not visible
+                            return false;
+                        }
+                    // falls through
+                    case 239 /* ModuleDeclaration */:
+                    case 235 /* ClassDeclaration */:
+                    case 236 /* InterfaceDeclaration */:
+                    case 237 /* TypeAliasDeclaration */:
+                    case 234 /* FunctionDeclaration */:
+                    case 238 /* EnumDeclaration */:
+                    case 243 /* ImportEqualsDeclaration */:
+                        // external module augmentation is always visible
+                        if (ts.isExternalModuleAugmentation(node)) {
+                            return true;
+                        }
+                        var parent = getDeclarationContainer(node);
+                        // If the node is not exported or it is not ambient module element (except import declaration)
+                        if (!(ts.getCombinedModifierFlags(node) & 1 /* Export */) &&
+                            !(node.kind !== 243 /* ImportEqualsDeclaration */ && parent.kind !== 274 /* SourceFile */ && parent.flags & 4194304 /* Ambient */)) {
+                            return isGlobalSourceFile(parent);
+                        }
+                        // Exported members/ambient module elements (exception import declaration) are visible if parent is visible
+                        return isDeclarationVisible(parent);
+                    case 152 /* PropertyDeclaration */:
+                    case 151 /* PropertySignature */:
+                    case 156 /* GetAccessor */:
+                    case 157 /* SetAccessor */:
+                    case 154 /* MethodDeclaration */:
+                    case 153 /* MethodSignature */:
+                        if (ts.hasModifier(node, 8 /* Private */ | 16 /* Protected */)) {
+                            // Private/protected properties/methods are not visible
+                            return false;
+                        }
+                    // Public properties/methods are visible if its parents are visible, so:
+                    // falls through
+                    case 155 /* Constructor */:
+                    case 159 /* ConstructSignature */:
+                    case 158 /* CallSignature */:
+                    case 160 /* IndexSignature */:
+                    case 149 /* Parameter */:
+                    case 240 /* ModuleBlock */:
+                    case 163 /* FunctionType */:
+                    case 164 /* ConstructorType */:
+                    case 166 /* TypeLiteral */:
+                    case 162 /* TypeReference */:
+                    case 167 /* ArrayType */:
+                    case 168 /* TupleType */:
+                    case 169 /* UnionType */:
+                    case 170 /* IntersectionType */:
+                    case 173 /* ParenthesizedType */:
+                        return isDeclarationVisible(node.parent);
+                    // Default binding, import specifier and namespace import is visible
+                    // only on demand so by default it is not visible
+                    case 245 /* ImportClause */:
+                    case 246 /* NamespaceImport */:
+                    case 248 /* ImportSpecifier */:
+                        return false;
+                    // Type parameters are always visible
+                    case 148 /* TypeParameter */:
+                    // Source file and namespace export are always visible
+                    case 274 /* SourceFile */:
+                    case 242 /* NamespaceExportDeclaration */:
+                        return true;
+                    // Export assignments do not create name bindings outside the module
+                    case 249 /* ExportAssignment */:
+                        return false;
+                    default:
+                        return false;
+                }
+            }
+        }
+        function collectLinkedAliases(node, setVisibility) {
+            var exportSymbol;
+            if (node.parent && node.parent.kind === 249 /* ExportAssignment */) {
+                exportSymbol = resolveName(node, node.escapedText, 67216319 /* Value */ | 67901928 /* Type */ | 1920 /* Namespace */ | 2097152 /* Alias */, /*nameNotFoundMessage*/ undefined, node, /*isUse*/ false);
+            }
+            else if (node.parent.kind === 252 /* ExportSpecifier */) {
+                exportSymbol = getTargetOfExportSpecifier(node.parent, 67216319 /* Value */ | 67901928 /* Type */ | 1920 /* Namespace */ | 2097152 /* Alias */);
+            }
+            var result;
+            if (exportSymbol) {
+                buildVisibleNodeList(exportSymbol.declarations);
+            }
+            return result;
+            function buildVisibleNodeList(declarations) {
+                ts.forEach(declarations, function (declaration) {
+                    var resultNode = getAnyImportSyntax(declaration) || declaration;
+                    if (setVisibility) {
+                        getNodeLinks(declaration).isVisible = true;
+                    }
+                    else {
+                        result = result || [];
+                        ts.pushIfUnique(result, resultNode);
+                    }
+                    if (ts.isInternalModuleImportEqualsDeclaration(declaration)) {
+                        // Add the referenced top container visible
+                        var internalModuleReference = declaration.moduleReference;
+                        var firstIdentifier = getFirstIdentifier(internalModuleReference);
+                        var importSymbol = resolveName(declaration, firstIdentifier.escapedText, 67216319 /* Value */ | 67901928 /* Type */ | 1920 /* Namespace */, undefined, undefined, /*isUse*/ false);
+                        if (importSymbol) {
+                            buildVisibleNodeList(importSymbol.declarations);
+                        }
+                    }
+                });
+            }
+        }
+        /**
+         * Push an entry on the type resolution stack. If an entry with the given target and the given property name
+         * is already on the stack, and no entries in between already have a type, then a circularity has occurred.
+         * In this case, the result values of the existing entry and all entries pushed after it are changed to false,
+         * and the value false is returned. Otherwise, the new entry is just pushed onto the stack, and true is returned.
+         * In order to see if the same query has already been done before, the target object and the propertyName both
+         * must match the one passed in.
+         *
+         * @param target The symbol, type, or signature whose type is being queried
+         * @param propertyName The property name that should be used to query the target for its type
+         */
+        function pushTypeResolution(target, propertyName) {
+            var resolutionCycleStartIndex = findResolutionCycleStartIndex(target, propertyName);
+            if (resolutionCycleStartIndex >= 0) {
+                // A cycle was found
+                var length_2 = resolutionTargets.length;
+                for (var i = resolutionCycleStartIndex; i < length_2; i++) {
+                    resolutionResults[i] = false;
+                }
+                return false;
+            }
+            resolutionTargets.push(target);
+            resolutionResults.push(/*items*/ true);
+            resolutionPropertyNames.push(propertyName);
+            return true;
+        }
+        function findResolutionCycleStartIndex(target, propertyName) {
+            for (var i = resolutionTargets.length - 1; i >= 0; i--) {
+                if (hasType(resolutionTargets[i], resolutionPropertyNames[i])) {
+                    return -1;
+                }
+                if (resolutionTargets[i] === target && resolutionPropertyNames[i] === propertyName) {
+                    return i;
+                }
+            }
+            return -1;
+        }
+        function hasType(target, propertyName) {
+            if (propertyName === 0 /* Type */) {
+                return !!getSymbolLinks(target).type;
+            }
+            if (propertyName === 2 /* DeclaredType */) {
+                return !!getSymbolLinks(target).declaredType;
+            }
+            if (propertyName === 1 /* ResolvedBaseConstructorType */) {
+                return !!target.resolvedBaseConstructorType;
+            }
+            if (propertyName === 3 /* ResolvedReturnType */) {
+                return !!target.resolvedReturnType;
+            }
+            if (propertyName === 4 /* ResolvedBaseConstraint */) {
+                var bc = target.resolvedBaseConstraint;
+                return !!bc && bc !== circularConstraintType;
+            }
+            return ts.Debug.fail("Unhandled TypeSystemPropertyName " + propertyName);
+        }
+        // Pop an entry from the type resolution stack and return its associated result value. The result value will
+        // be true if no circularities were detected, or false if a circularity was found.
+        function popTypeResolution() {
+            resolutionTargets.pop();
+            resolutionPropertyNames.pop();
+            return resolutionResults.pop();
+        }
+        function getDeclarationContainer(node) {
+            return ts.findAncestor(ts.getRootDeclaration(node), function (node) {
+                switch (node.kind) {
+                    case 232 /* VariableDeclaration */:
+                    case 233 /* VariableDeclarationList */:
+                    case 248 /* ImportSpecifier */:
+                    case 247 /* NamedImports */:
+                    case 246 /* NamespaceImport */:
+                    case 245 /* ImportClause */:
+                        return false;
+                    default:
+                        return true;
+                }
+            }).parent;
+        }
+        function getTypeOfPrototypeProperty(prototype) {
+            // TypeScript 1.0 spec (April 2014): 8.4
+            // Every class automatically contains a static property member named 'prototype',
+            // the type of which is an instantiation of the class type with type Any supplied as a type argument for each type parameter.
+            // It is an error to explicitly declare a static property member with the name 'prototype'.
+            var classType = getDeclaredTypeOfSymbol(getParentOfSymbol(prototype));
+            return classType.typeParameters ? createTypeReference(classType, ts.map(classType.typeParameters, function (_) { return anyType; })) : classType;
+        }
+        // Return the type of the given property in the given type, or undefined if no such property exists
+        function getTypeOfPropertyOfType(type, name) {
+            var prop = getPropertyOfType(type, name);
+            return prop ? getTypeOfSymbol(prop) : undefined;
+        }
+        function isTypeAny(type) {
+            return type && (type.flags & 1 /* Any */) !== 0;
+        }
+        // Return the type of a binding element parent. We check SymbolLinks first to see if a type has been
+        // assigned by contextual typing.
+        function getTypeForBindingElementParent(node) {
+            var symbol = getSymbolOfNode(node);
+            return symbol && getSymbolLinks(symbol).type || getTypeForVariableLikeDeclaration(node, /*includeOptionality*/ false);
+        }
+        function isComputedNonLiteralName(name) {
+            return name.kind === 147 /* ComputedPropertyName */ && !ts.isStringOrNumericLiteral(name.expression);
+        }
+        function getRestType(source, properties, symbol) {
+            source = filterType(source, function (t) { return !(t.flags & 24576 /* Nullable */); });
+            if (source.flags & 32768 /* Never */) {
+                return emptyObjectType;
+            }
+            if (source.flags & 262144 /* Union */) {
+                return mapType(source, function (t) { return getRestType(t, properties, symbol); });
+            }
+            var members = ts.createSymbolTable();
+            var names = ts.createUnderscoreEscapedMap();
+            for (var _i = 0, properties_2 = properties; _i < properties_2.length; _i++) {
+                var name = properties_2[_i];
+                names.set(ts.getTextOfPropertyName(name), true);
+            }
+            for (var _a = 0, _b = getPropertiesOfType(source); _a < _b.length; _a++) {
+                var prop = _b[_a];
+                var inNamesToRemove = names.has(prop.escapedName);
+                var isPrivate = ts.getDeclarationModifierFlagsFromSymbol(prop) & (8 /* Private */ | 16 /* Protected */);
+                var isSetOnlyAccessor = prop.flags & 65536 /* SetAccessor */ && !(prop.flags & 32768 /* GetAccessor */);
+                if (!inNamesToRemove && !isPrivate && !isClassMethod(prop) && !isSetOnlyAccessor) {
+                    members.set(prop.escapedName, getNonReadonlySymbol(prop));
+                }
+            }
+            var stringIndexInfo = getIndexInfoOfType(source, 0 /* String */);
+            var numberIndexInfo = getIndexInfoOfType(source, 1 /* Number */);
+            return createAnonymousType(symbol, members, ts.emptyArray, ts.emptyArray, stringIndexInfo, numberIndexInfo);
+        }
+        /** Return the inferred type for a binding element */
+        function getTypeForBindingElement(declaration) {
+            var pattern = declaration.parent;
+            var parentType = getTypeForBindingElementParent(pattern.parent);
+            // If parent has the unknown (error) type, then so does this binding element
+            if (parentType === errorType) {
+                return errorType;
+            }
+            // If no type was specified or inferred for parent,
+            // infer from the initializer of the binding element if one is present.
+            // Otherwise, go with the undefined type of the parent.
+            if (!parentType) {
+                return declaration.initializer ? checkDeclarationInitializer(declaration) : parentType;
+            }
+            if (isTypeAny(parentType)) {
+                return parentType;
+            }
+            var type;
+            if (pattern.kind === 180 /* ObjectBindingPattern */) {
+                if (declaration.dotDotDotToken) {
+                    if (parentType.flags & 2 /* Unknown */ || !isValidSpreadType(parentType)) {
+                        error(declaration, ts.Diagnostics.Rest_types_may_only_be_created_from_object_types);
+                        return errorType;
+                    }
+                    var literalMembers = [];
+                    for (var _i = 0, _a = pattern.elements; _i < _a.length; _i++) {
+                        var element = _a[_i];
+                        if (!element.dotDotDotToken) {
+                            literalMembers.push(element.propertyName || element.name);
+                        }
+                    }
+                    type = getRestType(parentType, literalMembers, declaration.symbol);
+                }
+                else {
+                    // Use explicitly specified property name ({ p: xxx } form), or otherwise the implied name ({ p } form)
+                    var name = declaration.propertyName || declaration.name;
+                    var isLate = isLateBindableName(name);
+                    var isWellKnown = ts.isComputedPropertyName(name) && ts.isWellKnownSymbolSyntactically(name.expression);
+                    if (!isLate && !isWellKnown && isComputedNonLiteralName(name)) {
+                        var exprType = checkExpression(name.expression);
+                        if (isTypeAssignableToKind(exprType, 3072 /* ESSymbolLike */)) {
+                            if (noImplicitAny) {
+                                error(declaration, ts.Diagnostics.Type_0_cannot_be_used_to_index_type_1, typeToString(exprType), typeToString(parentType));
+                            }
+                            return anyType;
+                        }
+                        var indexerType = isTypeAssignableToKind(exprType, 168 /* NumberLike */) && getIndexTypeOfType(parentType, 1 /* Number */) || getIndexTypeOfType(parentType, 0 /* String */);
+                        if (!indexerType && noImplicitAny && !compilerOptions.suppressImplicitAnyIndexErrors) {
+                            if (getIndexTypeOfType(parentType, 1 /* Number */)) {
+                                error(declaration, ts.Diagnostics.Element_implicitly_has_an_any_type_because_index_expression_is_not_of_type_number);
+                            }
+                            else {
+                                error(declaration, ts.Diagnostics.Element_implicitly_has_an_any_type_because_type_0_has_no_index_signature, typeToString(parentType));
+                            }
+                        }
+                        return indexerType || anyType;
+                    }
+                    // Use type of the specified property, or otherwise, for a numeric name, the type of the numeric index signature,
+                    // or otherwise the type of the string index signature.
+                    var nameType = isLate ? checkComputedPropertyName(name) : undefined;
+                    var text = isLate ? getLateBoundNameFromType(nameType) :
+                        isWellKnown ? ts.getPropertyNameForKnownSymbolName(ts.idText(name.expression.name)) :
+                            ts.getTextOfPropertyName(name);
+                    // Relax null check on ambient destructuring parameters, since the parameters have no implementation and are just documentation
+                    if (strictNullChecks && declaration.flags & 4194304 /* Ambient */ && ts.isParameterDeclaration(declaration)) {
+                        parentType = getNonNullableType(parentType);
+                    }
+                    if (isLate && nameType && !getPropertyOfType(parentType, text) && isTypeAssignableToKind(nameType, 3072 /* ESSymbolLike */)) {
+                        if (noImplicitAny) {
+                            error(declaration, ts.Diagnostics.Type_0_cannot_be_used_to_index_type_1, typeToString(nameType), typeToString(parentType));
+                        }
+                        return anyType;
+                    }
+                    var declaredType = getConstraintForLocation(getTypeOfPropertyOfType(parentType, text), declaration.name);
+                    type = declaredType && getFlowTypeOfReference(declaration, declaredType) ||
+                        isNumericLiteralName(text) && getIndexTypeOfType(parentType, 1 /* Number */) ||
+                        getIndexTypeOfType(parentType, 0 /* String */);
+                    if (!type) {
+                        error(name, ts.Diagnostics.Type_0_has_no_property_1_and_no_string_index_signature, typeToString(parentType), ts.declarationNameToString(name));
+                        return errorType;
+                    }
+                }
+            }
+            else {
+                // This elementType will be used if the specific property corresponding to this index is not
+                // present (aka the tuple element property). This call also checks that the parentType is in
+                // fact an iterable or array (depending on target language).
+                var elementType = checkIteratedTypeOrElementType(parentType, pattern, /*allowStringInput*/ false, /*allowAsyncIterables*/ false);
+                if (declaration.dotDotDotToken) {
+                    // Rest element has an array type with the same element type as the parent type
+                    type = createArrayType(elementType);
+                }
+                else {
+                    // Use specific property type when parent is a tuple or numeric index type when parent is an array
+                    var propName = "" + pattern.elements.indexOf(declaration);
+                    type = isTupleLikeType(parentType)
+                        ? getTypeOfPropertyOfType(parentType, propName)
+                        : elementType;
+                    if (!type) {
+                        if (isTupleType(parentType)) {
+                            error(declaration, ts.Diagnostics.Tuple_type_0_with_length_1_cannot_be_assigned_to_tuple_with_length_2, typeToString(parentType), getTypeReferenceArity(parentType), pattern.elements.length);
+                        }
+                        else {
+                            error(declaration, ts.Diagnostics.Type_0_has_no_property_1, typeToString(parentType), propName);
+                        }
+                        return errorType;
+                    }
+                }
+            }
+            // In strict null checking mode, if a default value of a non-undefined type is specified, remove
+            // undefined from the final type.
+            if (strictNullChecks && declaration.initializer && !(getFalsyFlags(checkExpressionCached(declaration.initializer)) & 8192 /* Undefined */)) {
+                type = getTypeWithFacts(type, 131072 /* NEUndefined */);
+            }
+            return declaration.initializer ?
+                getUnionType([type, checkExpressionCached(declaration.initializer)], 2 /* Subtype */) :
+                type;
+        }
+        function getTypeForDeclarationFromJSDocComment(declaration) {
+            var jsdocType = ts.getJSDocType(declaration);
+            if (jsdocType) {
+                return getTypeFromTypeNode(jsdocType);
+            }
+            return undefined;
+        }
+        function isNullOrUndefined(node) {
+            var expr = ts.skipParentheses(node);
+            return expr.kind === 95 /* NullKeyword */ || expr.kind === 71 /* Identifier */ && getResolvedSymbol(expr) === undefinedSymbol;
+        }
+        function isEmptyArrayLiteral(node) {
+            var expr = ts.skipParentheses(node);
+            return expr.kind === 183 /* ArrayLiteralExpression */ && expr.elements.length === 0;
+        }
+        function addOptionality(type, optional) {
+            if (optional === void 0) { optional = true; }
+            return strictNullChecks && optional ? getOptionalType(type) : type;
+        }
+        // Return the inferred type for a variable, parameter, or property declaration
+        function getTypeForVariableLikeDeclaration(declaration, includeOptionality) {
+            // A variable declared in a for..in statement is of type string, or of type keyof T when the
+            // right hand expression is of a type parameter type.
+            if (ts.isVariableDeclaration(declaration) && declaration.parent.parent.kind === 221 /* ForInStatement */) {
+                var indexType = getIndexType(checkNonNullExpression(declaration.parent.parent.expression));
+                return indexType.flags & (65536 /* TypeParameter */ | 1048576 /* Index */) ? getExtractStringType(indexType) : stringType;
+            }
+            if (ts.isVariableDeclaration(declaration) && declaration.parent.parent.kind === 222 /* ForOfStatement */) {
+                // checkRightHandSideOfForOf will return undefined if the for-of expression type was
+                // missing properties/signatures required to get its iteratedType (like
+                // [Symbol.iterator] or next). This may be because we accessed properties from anyType,
+                // or it may have led to an error inside getElementTypeOfIterable.
+                var forOfStatement = declaration.parent.parent;
+                return checkRightHandSideOfForOf(forOfStatement.expression, forOfStatement.awaitModifier) || anyType;
+            }
+            if (ts.isBindingPattern(declaration.parent)) {
+                return getTypeForBindingElement(declaration);
+            }
+            var isOptional = includeOptionality && (ts.isParameter(declaration) && isJSDocOptionalParameter(declaration)
+                || !ts.isBindingElement(declaration) && !ts.isVariableDeclaration(declaration) && !!declaration.questionToken);
+            // Use type from type annotation if one is present
+            var declaredType = tryGetTypeFromEffectiveTypeNode(declaration);
+            if (declaredType) {
+                return addOptionality(declaredType, isOptional);
+            }
+            if ((noImplicitAny || ts.isInJavaScriptFile(declaration)) &&
+                declaration.kind === 232 /* VariableDeclaration */ && !ts.isBindingPattern(declaration.name) &&
+                !(ts.getCombinedModifierFlags(declaration) & 1 /* Export */) && !(declaration.flags & 4194304 /* Ambient */)) {
+                // If --noImplicitAny is on or the declaration is in a Javascript file,
+                // use control flow tracked 'any' type for non-ambient, non-exported var or let variables with no
+                // initializer or a 'null' or 'undefined' initializer.
+                if (!(ts.getCombinedNodeFlags(declaration) & 2 /* Const */) && (!declaration.initializer || isNullOrUndefined(declaration.initializer))) {
+                    return autoType;
+                }
+                // Use control flow tracked 'any[]' type for non-ambient, non-exported variables with an empty array
+                // literal initializer.
+                if (declaration.initializer && isEmptyArrayLiteral(declaration.initializer)) {
+                    return autoArrayType;
+                }
+            }
+            if (declaration.kind === 149 /* Parameter */) {
+                var func = declaration.parent;
+                // For a parameter of a set accessor, use the type of the get accessor if one is present
+                if (func.kind === 157 /* SetAccessor */ && !hasNonBindableDynamicName(func)) {
+                    var getter = ts.getDeclarationOfKind(getSymbolOfNode(declaration.parent), 156 /* GetAccessor */);
+                    if (getter) {
+                        var getterSignature = getSignatureFromDeclaration(getter);
+                        var thisParameter = getAccessorThisParameter(func);
+                        if (thisParameter && declaration === thisParameter) {
+                            // Use the type from the *getter*
+                            ts.Debug.assert(!thisParameter.type);
+                            return getTypeOfSymbol(getterSignature.thisParameter);
+                        }
+                        return getReturnTypeOfSignature(getterSignature);
+                    }
+                }
+                // Use contextual parameter type if one is available
+                var type = void 0;
+                if (declaration.symbol.escapedName === "this") {
+                    type = getContextualThisParameterType(func);
+                }
+                else {
+                    type = getContextuallyTypedParameterType(declaration);
+                }
+                if (type) {
+                    return addOptionality(type, isOptional);
+                }
+            }
+            // Use the type of the initializer expression if one is present
+            if (declaration.initializer) {
+                var type = checkDeclarationInitializer(declaration);
+                return addOptionality(type, isOptional);
+            }
+            if (ts.isJsxAttribute(declaration)) {
+                // if JSX attribute doesn't have initializer, by default the attribute will have boolean value of true.
+                // I.e <Elem attr /> is sugar for <Elem attr={true} />
+                return trueType;
+            }
+            // If the declaration specifies a binding pattern, use the type implied by the binding pattern
+            if (ts.isBindingPattern(declaration.name)) {
+                return getTypeFromBindingPattern(declaration.name, /*includePatternInType*/ false, /*reportErrors*/ true);
+            }
+            // No type specified and nothing can be inferred
+            return undefined;
+        }
+        function getWidenedTypeFromJSSpecialPropertyDeclarations(symbol) {
+            // function/class/{} assignments are fresh declarations, not property assignments, so only add prototype assignments
+            var specialDeclaration = ts.getAssignedJavascriptInitializer(symbol.valueDeclaration);
+            if (specialDeclaration) {
+                return getWidenedLiteralType(checkExpressionCached(specialDeclaration));
+            }
+            var types = [];
+            var constructorTypes;
+            var definedInConstructor = false;
+            var definedInMethod = false;
+            var jsDocType;
+            var _loop_4 = function (declaration) {
+                var declarationInConstructor = false;
+                var expression = declaration.kind === 200 /* BinaryExpression */ ? declaration :
+                    declaration.kind === 185 /* PropertyAccessExpression */ ? ts.cast(declaration.parent, ts.isBinaryExpression) :
+                        undefined;
+                if (!expression) {
+                    return { value: errorType };
+                }
+                var special = ts.getSpecialPropertyAssignmentKind(expression);
+                if (special === 4 /* ThisProperty */) {
+                    var thisContainer = ts.getThisContainer(expression, /*includeArrowFunctions*/ false);
+                    // Properties defined in a constructor (or base constructor, or javascript constructor function) don't get undefined added.
+                    // Function expressions that are assigned to the prototype count as methods.
+                    declarationInConstructor = thisContainer.kind === 155 /* Constructor */ ||
+                        thisContainer.kind === 234 /* FunctionDeclaration */ ||
+                        (thisContainer.kind === 192 /* FunctionExpression */ && !ts.isPrototypePropertyAssignment(thisContainer.parent));
+                    if (declarationInConstructor) {
+                        definedInConstructor = true;
+                    }
+                    else {
+                        definedInMethod = true;
+                    }
+                }
+                // If there is a JSDoc type, use it
+                var type_1 = getTypeForDeclarationFromJSDocComment(expression.parent);
+                if (type_1) {
+                    var declarationType = getWidenedType(type_1);
+                    if (!jsDocType) {
+                        jsDocType = declarationType;
+                    }
+                    else if (jsDocType !== errorType && declarationType !== errorType &&
+                        !isTypeIdenticalTo(jsDocType, declarationType) &&
+                        !(symbol.flags & 67108864 /* JSContainer */)) {
+                        errorNextVariableOrPropertyDeclarationMustHaveSameType(jsDocType, declaration, declarationType);
+                    }
+                }
+                else if (!jsDocType) {
+                    // If we don't have an explicit JSDoc type, get the type from the expression.
+                    var type_2 = getWidenedLiteralType(checkExpressionCached(expression.right));
+                    if (ts.getObjectFlags(type_2) & 16 /* Anonymous */ &&
+                        special === 2 /* ModuleExports */ &&
+                        symbol.escapedName === "export=" /* ExportEquals */) {
+                        var exportedType_1 = resolveStructuredTypeMembers(type_2);
+                        var members_3 = ts.createSymbolTable();
+                        ts.copyEntries(exportedType_1.members, members_3);
+                        symbol.exports.forEach(function (s, name) {
+                            if (members_3.has(name)) {
+                                var exportedMember = exportedType_1.members.get(name);
+                                var union = createSymbol(s.flags | exportedMember.flags, name);
+                                union.type = getUnionType([getTypeOfSymbol(s), getTypeOfSymbol(exportedMember)]);
+                                members_3.set(name, union);
+                            }
+                            else {
+                                members_3.set(name, s);
+                            }
+                        });
+                        type_2 = createAnonymousType(exportedType_1.symbol, members_3, exportedType_1.callSignatures, exportedType_1.constructSignatures, exportedType_1.stringIndexInfo, exportedType_1.numberIndexInfo);
+                    }
+                    var anyedType = type_2;
+                    if (isEmptyArrayLiteralType(type_2)) {
+                        anyedType = anyArrayType;
+                        if (noImplicitAny) {
+                            reportImplicitAnyError(expression, anyArrayType);
+                        }
+                    }
+                    types.push(anyedType);
+                    if (declarationInConstructor) {
+                        (constructorTypes || (constructorTypes = [])).push(anyedType);
+                    }
+                }
+            };
+            for (var _i = 0, _a = symbol.declarations; _i < _a.length; _i++) {
+                var declaration = _a[_i];
+                var state_2 = _loop_4(declaration);
+                if (typeof state_2 === "object")
+                    return state_2.value;
+            }
+            var type = jsDocType;
+            if (!type) {
+                // use only the constructor types unless they were only assigned null | undefined (including widening variants)
+                if (definedInMethod) {
+                    var propType = getTypeOfSpecialPropertyOfBaseType(symbol);
+                    if (propType) {
+                        (constructorTypes || (constructorTypes = [])).push(propType);
+                        definedInConstructor = true;
+                    }
+                }
+                var sourceTypes = ts.some(constructorTypes, function (t) { return !!(t.flags & ~(24576 /* Nullable */ | 134217728 /* ContainsWideningType */)); }) ? constructorTypes : types; // TODO: GH#18217
+                type = getUnionType(sourceTypes, 2 /* Subtype */);
+            }
+            var widened = getWidenedType(addOptionality(type, definedInMethod && !definedInConstructor));
+            if (filterType(widened, function (t) { return !!(t.flags & ~24576 /* Nullable */); }) === neverType) {
+                if (noImplicitAny) {
+                    reportImplicitAnyError(symbol.valueDeclaration, anyType);
+                }
+                return anyType;
+            }
+            return widened;
+        }
+        /** check for definition in base class if any declaration is in a class */
+        function getTypeOfSpecialPropertyOfBaseType(specialProperty) {
+            var parentDeclaration = ts.forEach(specialProperty.declarations, function (d) {
+                var parent = ts.getThisContainer(d, /*includeArrowFunctions*/ false).parent;
+                return ts.isClassLike(parent) && parent;
+            });
+            if (parentDeclaration) {
+                var classType = getDeclaredTypeOfSymbol(getSymbolOfNode(parentDeclaration));
+                var baseClassType = classType && getBaseTypes(classType)[0];
+                if (baseClassType) {
+                    return getTypeOfPropertyOfType(baseClassType, specialProperty.escapedName);
+                }
+            }
+        }
+        // Return the type implied by a binding pattern element. This is the type of the initializer of the element if
+        // one is present. Otherwise, if the element is itself a binding pattern, it is the type implied by the binding
+        // pattern. Otherwise, it is the type any.
+        function getTypeFromBindingElement(element, includePatternInType, reportErrors) {
+            if (element.initializer) {
+                return checkDeclarationInitializer(element);
+            }
+            if (ts.isBindingPattern(element.name)) {
+                return getTypeFromBindingPattern(element.name, includePatternInType, reportErrors);
+            }
+            if (reportErrors && noImplicitAny && !declarationBelongsToPrivateAmbientMember(element)) {
+                reportImplicitAnyError(element, anyType);
+            }
+            return anyType;
+        }
+        // Return the type implied by an object binding pattern
+        function getTypeFromObjectBindingPattern(pattern, includePatternInType, reportErrors) {
+            var members = ts.createSymbolTable();
+            var stringIndexInfo;
+            var objectFlags = 128 /* ObjectLiteral */;
+            ts.forEach(pattern.elements, function (e) {
+                var name = e.propertyName || e.name;
+                if (isComputedNonLiteralName(name)) {
+                    // do not include computed properties in the implied type
+                    objectFlags |= 512 /* ObjectLiteralPatternWithComputedProperties */;
+                    return;
+                }
+                if (e.dotDotDotToken) {
+                    stringIndexInfo = createIndexInfo(anyType, /*isReadonly*/ false);
+                    return;
+                }
+                var text = ts.getTextOfPropertyName(name);
+                var flags = 4 /* Property */ | (e.initializer ? 16777216 /* Optional */ : 0);
+                var symbol = createSymbol(flags, text);
+                symbol.type = getTypeFromBindingElement(e, includePatternInType, reportErrors);
+                symbol.bindingElement = e;
+                members.set(symbol.escapedName, symbol);
+            });
+            var result = createAnonymousType(undefined, members, ts.emptyArray, ts.emptyArray, stringIndexInfo, undefined);
+            result.flags |= 268435456 /* ContainsObjectLiteral */;
+            result.objectFlags |= objectFlags;
+            if (includePatternInType) {
+                result.pattern = pattern;
+            }
+            return result;
+        }
+        // Return the type implied by an array binding pattern
+        function getTypeFromArrayBindingPattern(pattern, includePatternInType, reportErrors) {
+            var elements = pattern.elements;
+            var lastElement = ts.lastOrUndefined(elements);
+            if (!lastElement || (!ts.isOmittedExpression(lastElement) && lastElement.dotDotDotToken)) {
+                return languageVersion >= 2 /* ES2015 */ ? createIterableType(anyType) : anyArrayType;
+            }
+            // If the pattern has at least one element, and no rest element, then it should imply a tuple type.
+            var elementTypes = ts.map(elements, function (e) { return ts.isOmittedExpression(e) ? anyType : getTypeFromBindingElement(e, includePatternInType, reportErrors); });
+            var result = createTupleType(elementTypes);
+            if (includePatternInType) {
+                result = cloneTypeReference(result);
+                result.pattern = pattern;
+            }
+            return result;
+        }
+        // Return the type implied by a binding pattern. This is the type implied purely by the binding pattern itself
+        // and without regard to its context (i.e. without regard any type annotation or initializer associated with the
+        // declaration in which the binding pattern is contained). For example, the implied type of [x, y] is [any, any]
+        // and the implied type of { x, y: z = 1 } is { x: any; y: number; }. The type implied by a binding pattern is
+        // used as the contextual type of an initializer associated with the binding pattern. Also, for a destructuring
+        // parameter with no type annotation or initializer, the type implied by the binding pattern becomes the type of
+        // the parameter.
+        function getTypeFromBindingPattern(pattern, includePatternInType, reportErrors) {
+            if (includePatternInType === void 0) { includePatternInType = false; }
+            if (reportErrors === void 0) { reportErrors = false; }
+            return pattern.kind === 180 /* ObjectBindingPattern */
+                ? getTypeFromObjectBindingPattern(pattern, includePatternInType, reportErrors)
+                : getTypeFromArrayBindingPattern(pattern, includePatternInType, reportErrors);
+        }
+        // Return the type associated with a variable, parameter, or property declaration. In the simple case this is the type
+        // specified in a type annotation or inferred from an initializer. However, in the case of a destructuring declaration it
+        // is a bit more involved. For example:
+        //
+        //   var [x, s = ""] = [1, "one"];
+        //
+        // Here, the array literal [1, "one"] is contextually typed by the type [any, string], which is the implied type of the
+        // binding pattern [x, s = ""]. Because the contextual type is a tuple type, the resulting type of [1, "one"] is the
+        // tuple type [number, string]. Thus, the type inferred for 'x' is number and the type inferred for 's' is string.
+        function getWidenedTypeForVariableLikeDeclaration(declaration, reportErrors) {
+            var type = getTypeForVariableLikeDeclaration(declaration, /*includeOptionality*/ true);
+            if (type) {
+                if (reportErrors) {
+                    reportErrorsFromWidening(declaration, type);
+                }
+                // always widen a 'unique symbol' type if the type was created for a different declaration.
+                if (type.flags & 2048 /* UniqueESSymbol */ && (ts.isBindingElement(declaration) || !declaration.type) && type.symbol !== getSymbolOfNode(declaration)) {
+                    type = esSymbolType;
+                }
+                return getWidenedType(type);
+            }
+            // Rest parameters default to type any[], other parameters default to type any
+            type = ts.isParameter(declaration) && declaration.dotDotDotToken ? anyArrayType : anyType;
+            // Report implicit any errors unless this is a private property within an ambient declaration
+            if (reportErrors && noImplicitAny) {
+                if (!declarationBelongsToPrivateAmbientMember(declaration)) {
+                    reportImplicitAnyError(declaration, type);
+                }
+            }
+            return type;
+        }
+        function declarationBelongsToPrivateAmbientMember(declaration) {
+            var root = ts.getRootDeclaration(declaration);
+            var memberDeclaration = root.kind === 149 /* Parameter */ ? root.parent : root;
+            return isPrivateWithinAmbient(memberDeclaration);
+        }
+        function tryGetTypeFromEffectiveTypeNode(declaration) {
+            var typeNode = ts.getEffectiveTypeAnnotationNode(declaration);
+            if (typeNode) {
+                return getTypeFromTypeNode(typeNode);
+            }
+        }
+        function getTypeOfVariableOrParameterOrProperty(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (!links.type) {
+                // Handle prototype property
+                if (symbol.flags & 4194304 /* Prototype */) {
+                    return links.type = getTypeOfPrototypeProperty(symbol);
+                }
+                // CommonsJS require and module both have type any.
+                if (symbol === requireSymbol || symbol === moduleSymbol) {
+                    return links.type = anyType;
+                }
+                // Handle catch clause variables
+                var declaration = symbol.valueDeclaration;
+                if (ts.isCatchClauseVariableDeclarationOrBindingElement(declaration)) {
+                    return links.type = anyType;
+                }
+                // Handle export default expressions
+                if (ts.isSourceFile(declaration)) {
+                    var jsonSourceFile = ts.cast(declaration, ts.isJsonSourceFile);
+                    return links.type = jsonSourceFile.statements.length ? checkExpression(jsonSourceFile.statements[0].expression) : emptyObjectType;
+                }
+                if (declaration.kind === 249 /* ExportAssignment */) {
+                    return links.type = checkExpression(declaration.expression);
+                }
+                if (ts.isInJavaScriptFile(declaration) && ts.isJSDocPropertyLikeTag(declaration) && declaration.typeExpression) {
+                    return links.type = getTypeFromTypeNode(declaration.typeExpression.type);
+                }
+                // Handle variable, parameter or property
+                if (!pushTypeResolution(symbol, 0 /* Type */)) {
+                    return errorType;
+                }
+                var type = void 0;
+                // Handle certain special assignment kinds, which happen to union across multiple declarations:
+                // * module.exports = expr
+                // * exports.p = expr
+                // * this.p = expr
+                // * className.prototype.method = expr
+                if (declaration.kind === 200 /* BinaryExpression */ ||
+                    declaration.kind === 185 /* PropertyAccessExpression */ && declaration.parent.kind === 200 /* BinaryExpression */) {
+                    type = getWidenedTypeFromJSSpecialPropertyDeclarations(symbol);
+                }
+                else if (ts.isJSDocPropertyLikeTag(declaration)
+                    || ts.isPropertyAccessExpression(declaration)
+                    || ts.isIdentifier(declaration)
+                    || ts.isClassDeclaration(declaration)
+                    || ts.isFunctionDeclaration(declaration)
+                    || (ts.isMethodDeclaration(declaration) && !ts.isObjectLiteralMethod(declaration))
+                    || ts.isMethodSignature(declaration)) {
+                    // Symbol is property of some kind that is merged with something - should use `getTypeOfFuncClassEnumModule` and not `getTypeOfVariableOrParameterOrProperty`
+                    if (symbol.flags & (16 /* Function */ | 8192 /* Method */ | 32 /* Class */ | 384 /* Enum */ | 512 /* ValueModule */)) {
+                        return getTypeOfFuncClassEnumModule(symbol);
+                    }
+                    type = tryGetTypeFromEffectiveTypeNode(declaration) || anyType;
+                }
+                else if (ts.isPropertyAssignment(declaration)) {
+                    type = tryGetTypeFromEffectiveTypeNode(declaration) || checkPropertyAssignment(declaration);
+                }
+                else if (ts.isJsxAttribute(declaration)) {
+                    type = tryGetTypeFromEffectiveTypeNode(declaration) || checkJsxAttribute(declaration);
+                }
+                else if (ts.isShorthandPropertyAssignment(declaration)) {
+                    type = tryGetTypeFromEffectiveTypeNode(declaration) || checkExpressionForMutableLocation(declaration.name, 0 /* Normal */);
+                }
+                else if (ts.isObjectLiteralMethod(declaration)) {
+                    type = tryGetTypeFromEffectiveTypeNode(declaration) || checkObjectLiteralMethod(declaration, 0 /* Normal */);
+                }
+                else if (ts.isParameter(declaration)
+                    || ts.isPropertyDeclaration(declaration)
+                    || ts.isPropertySignature(declaration)
+                    || ts.isVariableDeclaration(declaration)
+                    || ts.isBindingElement(declaration)) {
+                    type = getWidenedTypeForVariableLikeDeclaration(declaration, /*reportErrors*/ true);
+                }
+                else {
+                    return ts.Debug.fail("Unhandled declaration kind! " + ts.Debug.showSyntaxKind(declaration) + " for " + ts.Debug.showSymbol(symbol));
+                }
+                if (!popTypeResolution()) {
+                    type = reportCircularityError(symbol);
+                }
+                links.type = type;
+            }
+            return links.type;
+        }
+        function getAnnotatedAccessorType(accessor) {
+            if (accessor) {
+                if (accessor.kind === 156 /* GetAccessor */) {
+                    var getterTypeAnnotation = ts.getEffectiveReturnTypeNode(accessor);
+                    return getterTypeAnnotation && getTypeFromTypeNode(getterTypeAnnotation);
+                }
+                else {
+                    var setterTypeAnnotation = ts.getEffectiveSetAccessorTypeAnnotationNode(accessor);
+                    return setterTypeAnnotation && getTypeFromTypeNode(setterTypeAnnotation);
+                }
+            }
+            return undefined;
+        }
+        function getAnnotatedAccessorThisParameter(accessor) {
+            var parameter = getAccessorThisParameter(accessor);
+            return parameter && parameter.symbol;
+        }
+        function getThisTypeOfDeclaration(declaration) {
+            return getThisTypeOfSignature(getSignatureFromDeclaration(declaration));
+        }
+        function getTypeOfAccessors(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (!links.type) {
+                var getter = ts.getDeclarationOfKind(symbol, 156 /* GetAccessor */);
+                var setter = ts.getDeclarationOfKind(symbol, 157 /* SetAccessor */);
+                if (getter && ts.isInJavaScriptFile(getter)) {
+                    var jsDocType = getTypeForDeclarationFromJSDocComment(getter);
+                    if (jsDocType) {
+                        return links.type = jsDocType;
+                    }
+                }
+                if (!pushTypeResolution(symbol, 0 /* Type */)) {
+                    return errorType;
+                }
+                var type = void 0;
+                // First try to see if the user specified a return type on the get-accessor.
+                var getterReturnType = getAnnotatedAccessorType(getter);
+                if (getterReturnType) {
+                    type = getterReturnType;
+                }
+                else {
+                    // If the user didn't specify a return type, try to use the set-accessor's parameter type.
+                    var setterParameterType = getAnnotatedAccessorType(setter);
+                    if (setterParameterType) {
+                        type = setterParameterType;
+                    }
+                    else {
+                        // If there are no specified types, try to infer it from the body of the get accessor if it exists.
+                        if (getter && getter.body) {
+                            type = getReturnTypeFromBody(getter);
+                        }
+                        // Otherwise, fall back to 'any'.
+                        else {
+                            if (noImplicitAny) {
+                                if (setter) {
+                                    error(setter, ts.Diagnostics.Property_0_implicitly_has_type_any_because_its_set_accessor_lacks_a_parameter_type_annotation, symbolToString(symbol));
+                                }
+                                else {
+                                    ts.Debug.assert(!!getter, "there must existed getter as we are current checking either setter or getter in this function");
+                                    error(getter, ts.Diagnostics.Property_0_implicitly_has_type_any_because_its_get_accessor_lacks_a_return_type_annotation, symbolToString(symbol));
+                                }
+                            }
+                            type = anyType;
+                        }
+                    }
+                }
+                if (!popTypeResolution()) {
+                    type = anyType;
+                    if (noImplicitAny) {
+                        var getter_1 = ts.getDeclarationOfKind(symbol, 156 /* GetAccessor */);
+                        error(getter_1, ts.Diagnostics._0_implicitly_has_return_type_any_because_it_does_not_have_a_return_type_annotation_and_is_referenced_directly_or_indirectly_in_one_of_its_return_expressions, symbolToString(symbol));
+                    }
+                }
+                links.type = type;
+            }
+            return links.type;
+        }
+        function getBaseTypeVariableOfClass(symbol) {
+            var baseConstructorType = getBaseConstructorTypeOfClass(getDeclaredTypeOfClassOrInterface(symbol));
+            return baseConstructorType.flags & 2162688 /* TypeVariable */ ? baseConstructorType : undefined;
+        }
+        function getTypeOfFuncClassEnumModule(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (!links.type) {
+                var jsDeclaration = ts.getDeclarationOfJSInitializer(symbol.valueDeclaration);
+                if (jsDeclaration) {
+                    var jsSymbol = getSymbolOfNode(jsDeclaration);
+                    if (jsSymbol && (ts.hasEntries(jsSymbol.exports) || ts.hasEntries(jsSymbol.members))) {
+                        symbol = cloneSymbol(symbol);
+                        // note:we overwrite links because we just cloned the symbol
+                        links = symbol;
+                        if (ts.hasEntries(jsSymbol.exports)) {
+                            symbol.exports = symbol.exports || ts.createSymbolTable();
+                            mergeSymbolTable(symbol.exports, jsSymbol.exports);
+                        }
+                        if (ts.hasEntries(jsSymbol.members)) {
+                            symbol.members = symbol.members || ts.createSymbolTable();
+                            mergeSymbolTable(symbol.members, jsSymbol.members);
+                        }
+                    }
+                }
+                if (symbol.flags & 1536 /* Module */ && ts.isShorthandAmbientModuleSymbol(symbol)) {
+                    links.type = anyType;
+                }
+                else if (symbol.valueDeclaration.kind === 200 /* BinaryExpression */ ||
+                    symbol.valueDeclaration.kind === 185 /* PropertyAccessExpression */ && symbol.valueDeclaration.parent.kind === 200 /* BinaryExpression */) {
+                    links.type = getWidenedTypeFromJSSpecialPropertyDeclarations(symbol);
+                }
+                else {
+                    var type = createObjectType(16 /* Anonymous */, symbol);
+                    if (symbol.flags & 32 /* Class */) {
+                        var baseTypeVariable = getBaseTypeVariableOfClass(symbol);
+                        links.type = baseTypeVariable ? getIntersectionType([type, baseTypeVariable]) : type;
+                    }
+                    else {
+                        links.type = strictNullChecks && symbol.flags & 16777216 /* Optional */ ? getOptionalType(type) : type;
+                    }
+                }
+            }
+            return links.type;
+        }
+        function getTypeOfEnumMember(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (!links.type) {
+                links.type = getDeclaredTypeOfEnumMember(symbol);
+            }
+            return links.type;
+        }
+        function getTypeOfAlias(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (!links.type) {
+                var targetSymbol = resolveAlias(symbol);
+                // It only makes sense to get the type of a value symbol. If the result of resolving
+                // the alias is not a value, then it has no type. To get the type associated with a
+                // type symbol, call getDeclaredTypeOfSymbol.
+                // This check is important because without it, a call to getTypeOfSymbol could end
+                // up recursively calling getTypeOfAlias, causing a stack overflow.
+                links.type = targetSymbol.flags & 67216319 /* Value */
+                    ? getTypeOfSymbol(targetSymbol)
+                    : errorType;
+            }
+            return links.type;
+        }
+        function getTypeOfInstantiatedSymbol(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (!links.type) {
+                if (symbolInstantiationDepth === 100) {
+                    error(symbol.valueDeclaration, ts.Diagnostics.Generic_type_instantiation_is_excessively_deep_and_possibly_infinite);
+                    links.type = errorType;
+                }
+                else {
+                    if (!pushTypeResolution(symbol, 0 /* Type */)) {
+                        return errorType;
+                    }
+                    symbolInstantiationDepth++;
+                    var type = instantiateType(getTypeOfSymbol(links.target), links.mapper);
+                    symbolInstantiationDepth--;
+                    if (!popTypeResolution()) {
+                        type = reportCircularityError(symbol);
+                    }
+                    links.type = type;
+                }
+            }
+            return links.type;
+        }
+        function reportCircularityError(symbol) {
+            // Check if variable has type annotation that circularly references the variable itself
+            if (ts.getEffectiveTypeAnnotationNode(symbol.valueDeclaration)) {
+                error(symbol.valueDeclaration, ts.Diagnostics._0_is_referenced_directly_or_indirectly_in_its_own_type_annotation, symbolToString(symbol));
+                return errorType;
+            }
+            // Otherwise variable has initializer that circularly references the variable itself
+            if (noImplicitAny) {
+                error(symbol.valueDeclaration, ts.Diagnostics._0_implicitly_has_type_any_because_it_does_not_have_a_type_annotation_and_is_referenced_directly_or_indirectly_in_its_own_initializer, symbolToString(symbol));
+            }
+            return anyType;
+        }
+        function getTypeOfSymbol(symbol) {
+            if (ts.getCheckFlags(symbol) & 1 /* Instantiated */) {
+                return getTypeOfInstantiatedSymbol(symbol);
+            }
+            if (ts.getCheckFlags(symbol) & 2048 /* ReverseMapped */) {
+                return getTypeOfReverseMappedSymbol(symbol);
+            }
+            if (symbol.flags & (3 /* Variable */ | 4 /* Property */)) {
+                return getTypeOfVariableOrParameterOrProperty(symbol);
+            }
+            if (symbol.flags & (16 /* Function */ | 8192 /* Method */ | 32 /* Class */ | 384 /* Enum */ | 512 /* ValueModule */)) {
+                return getTypeOfFuncClassEnumModule(symbol);
+            }
+            if (symbol.flags & 8 /* EnumMember */) {
+                return getTypeOfEnumMember(symbol);
+            }
+            if (symbol.flags & 98304 /* Accessor */) {
+                return getTypeOfAccessors(symbol);
+            }
+            if (symbol.flags & 2097152 /* Alias */) {
+                return getTypeOfAlias(symbol);
+            }
+            return errorType;
+        }
+        function isReferenceToType(type, target) {
+            return type !== undefined
+                && target !== undefined
+                && (ts.getObjectFlags(type) & 4 /* Reference */) !== 0
+                && type.target === target;
+        }
+        function getTargetType(type) {
+            return ts.getObjectFlags(type) & 4 /* Reference */ ? type.target : type;
+        }
+        // TODO: GH#18217 If `checkBase` is undefined, we should not call this because this will always return false.
+        function hasBaseType(type, checkBase) {
+            return check(type);
+            function check(type) {
+                if (ts.getObjectFlags(type) & (3 /* ClassOrInterface */ | 4 /* Reference */)) {
+                    var target = getTargetType(type);
+                    return target === checkBase || ts.some(getBaseTypes(target), check);
+                }
+                else if (type.flags & 524288 /* Intersection */) {
+                    return ts.some(type.types, check);
+                }
+                return false;
+            }
+        }
+        // Appends the type parameters given by a list of declarations to a set of type parameters and returns the resulting set.
+        // The function allocates a new array if the input type parameter set is undefined, but otherwise it modifies the set
+        // in-place and returns the same array.
+        function appendTypeParameters(typeParameters, declarations) {
+            for (var _i = 0, declarations_2 = declarations; _i < declarations_2.length; _i++) {
+                var declaration = declarations_2[_i];
+                typeParameters = ts.appendIfUnique(typeParameters, getDeclaredTypeOfTypeParameter(getSymbolOfNode(declaration)));
+            }
+            return typeParameters;
+        }
+        // Return the outer type parameters of a node or undefined if the node has no outer type parameters.
+        function getOuterTypeParameters(node, includeThisTypes) {
+            while (true) {
+                node = node.parent; // TODO: GH#18217 Use SourceFile kind check instead
+                if (!node) {
+                    return undefined;
+                }
+                switch (node.kind) {
+                    case 235 /* ClassDeclaration */:
+                    case 205 /* ClassExpression */:
+                    case 236 /* InterfaceDeclaration */:
+                    case 158 /* CallSignature */:
+                    case 159 /* ConstructSignature */:
+                    case 153 /* MethodSignature */:
+                    case 163 /* FunctionType */:
+                    case 164 /* ConstructorType */:
+                    case 284 /* JSDocFunctionType */:
+                    case 234 /* FunctionDeclaration */:
+                    case 154 /* MethodDeclaration */:
+                    case 192 /* FunctionExpression */:
+                    case 193 /* ArrowFunction */:
+                    case 237 /* TypeAliasDeclaration */:
+                    case 296 /* JSDocTemplateTag */:
+                    case 297 /* JSDocTypedefTag */:
+                    case 292 /* JSDocCallbackTag */:
+                    case 177 /* MappedType */:
+                    case 171 /* ConditionalType */:
+                        var outerTypeParameters = getOuterTypeParameters(node, includeThisTypes);
+                        if (node.kind === 177 /* MappedType */) {
+                            return ts.append(outerTypeParameters, getDeclaredTypeOfTypeParameter(getSymbolOfNode(node.typeParameter)));
+                        }
+                        else if (node.kind === 171 /* ConditionalType */) {
+                            return ts.concatenate(outerTypeParameters, getInferTypeParameters(node));
+                        }
+                        var outerAndOwnTypeParameters = appendTypeParameters(outerTypeParameters, ts.getEffectiveTypeParameterDeclarations(node));
+                        var thisType = includeThisTypes &&
+                            (node.kind === 235 /* ClassDeclaration */ || node.kind === 205 /* ClassExpression */ || node.kind === 236 /* InterfaceDeclaration */) &&
+                            getDeclaredTypeOfClassOrInterface(getSymbolOfNode(node)).thisType;
+                        return thisType ? ts.append(outerAndOwnTypeParameters, thisType) : outerAndOwnTypeParameters;
+                }
+            }
+        }
+        // The outer type parameters are those defined by enclosing generic classes, methods, or functions.
+        function getOuterTypeParametersOfClassOrInterface(symbol) {
+            var declaration = symbol.flags & 32 /* Class */ ? symbol.valueDeclaration : ts.getDeclarationOfKind(symbol, 236 /* InterfaceDeclaration */);
+            return getOuterTypeParameters(declaration);
+        }
+        // The local type parameters are the combined set of type parameters from all declarations of the class,
+        // interface, or type alias.
+        function getLocalTypeParametersOfClassOrInterfaceOrTypeAlias(symbol) {
+            var result;
+            for (var _i = 0, _a = symbol.declarations; _i < _a.length; _i++) {
+                var node = _a[_i];
+                if (node.kind === 236 /* InterfaceDeclaration */ ||
+                    node.kind === 235 /* ClassDeclaration */ ||
+                    node.kind === 205 /* ClassExpression */ ||
+                    ts.isTypeAlias(node)) {
+                    var declaration = node;
+                    result = appendTypeParameters(result, ts.getEffectiveTypeParameterDeclarations(declaration));
+                }
+            }
+            return result;
+        }
+        // The full set of type parameters for a generic class or interface type consists of its outer type parameters plus
+        // its locally declared type parameters.
+        function getTypeParametersOfClassOrInterface(symbol) {
+            return ts.concatenate(getOuterTypeParametersOfClassOrInterface(symbol), getLocalTypeParametersOfClassOrInterfaceOrTypeAlias(symbol));
+        }
+        // A type is a mixin constructor if it has a single construct signature taking no type parameters and a single
+        // rest parameter of type any[].
+        function isMixinConstructorType(type) {
+            var signatures = getSignaturesOfType(type, 1 /* Construct */);
+            if (signatures.length === 1) {
+                var s = signatures[0];
+                return !s.typeParameters && s.parameters.length === 1 && s.hasRestParameter && getTypeOfParameter(s.parameters[0]) === anyArrayType;
+            }
+            return false;
+        }
+        function isConstructorType(type) {
+            if (isValidBaseType(type) && getSignaturesOfType(type, 1 /* Construct */).length > 0) {
+                return true;
+            }
+            if (type.flags & 2162688 /* TypeVariable */) {
+                var constraint = getBaseConstraintOfType(type);
+                return !!constraint && isValidBaseType(constraint) && isMixinConstructorType(constraint);
+            }
+            return false;
+        }
+        function getBaseTypeNodeOfClass(type) {
+            var decl = type.symbol.valueDeclaration;
+            if (ts.isInJavaScriptFile(decl)) {
+                // Prefer an @augments tag because it may have type parameters.
+                var tag = ts.getJSDocAugmentsTag(decl);
+                if (tag) {
+                    return tag.class;
+                }
+            }
+            return ts.getClassExtendsHeritageClauseElement(decl);
+        }
+        function getConstructorsForTypeArguments(type, typeArgumentNodes, location) {
+            var typeArgCount = ts.length(typeArgumentNodes);
+            var isJavaScript = ts.isInJavaScriptFile(location);
+            return ts.filter(getSignaturesOfType(type, 1 /* Construct */), function (sig) { return (isJavaScript || typeArgCount >= getMinTypeArgumentCount(sig.typeParameters)) && typeArgCount <= ts.length(sig.typeParameters); });
+        }
+        function getInstantiatedConstructorsForTypeArguments(type, typeArgumentNodes, location) {
+            var signatures = getConstructorsForTypeArguments(type, typeArgumentNodes, location);
+            var typeArguments = ts.map(typeArgumentNodes, getTypeFromTypeNode);
+            return ts.sameMap(signatures, function (sig) { return ts.some(sig.typeParameters) ? getSignatureInstantiation(sig, typeArguments, ts.isInJavaScriptFile(location)) : sig; });
+        }
+        /**
+         * The base constructor of a class can resolve to
+         * * undefinedType if the class has no extends clause,
+         * * unknownType if an error occurred during resolution of the extends expression,
+         * * nullType if the extends expression is the null value,
+         * * anyType if the extends expression has type any, or
+         * * an object type with at least one construct signature.
+         */
+        function getBaseConstructorTypeOfClass(type) {
+            if (!type.resolvedBaseConstructorType) {
+                var decl = type.symbol.valueDeclaration;
+                var extended = ts.getClassExtendsHeritageClauseElement(decl);
+                var baseTypeNode = getBaseTypeNodeOfClass(type);
+                if (!baseTypeNode) {
+                    return type.resolvedBaseConstructorType = undefinedType;
+                }
+                if (!pushTypeResolution(type, 1 /* ResolvedBaseConstructorType */)) {
+                    return errorType;
+                }
+                var baseConstructorType = checkExpression(baseTypeNode.expression);
+                if (extended && baseTypeNode !== extended) {
+                    ts.Debug.assert(!extended.typeArguments); // Because this is in a JS file, and baseTypeNode is in an @extends tag
+                    checkExpression(extended.expression);
+                }
+                if (baseConstructorType.flags & (131072 /* Object */ | 524288 /* Intersection */)) {
+                    // Resolving the members of a class requires us to resolve the base class of that class.
+                    // We force resolution here such that we catch circularities now.
+                    resolveStructuredTypeMembers(baseConstructorType);
+                }
+                if (!popTypeResolution()) {
+                    error(type.symbol.valueDeclaration, ts.Diagnostics._0_is_referenced_directly_or_indirectly_in_its_own_base_expression, symbolToString(type.symbol));
+                    return type.resolvedBaseConstructorType = errorType;
+                }
+                if (!(baseConstructorType.flags & 1 /* Any */) && baseConstructorType !== nullWideningType && !isConstructorType(baseConstructorType)) {
+                    error(baseTypeNode.expression, ts.Diagnostics.Type_0_is_not_a_constructor_function_type, typeToString(baseConstructorType));
+                    return type.resolvedBaseConstructorType = errorType;
+                }
+                type.resolvedBaseConstructorType = baseConstructorType;
+            }
+            return type.resolvedBaseConstructorType;
+        }
+        function getBaseTypes(type) {
+            if (!type.resolvedBaseTypes) {
+                if (type.objectFlags & 8 /* Tuple */) {
+                    type.resolvedBaseTypes = [createArrayType(getUnionType(type.typeParameters))];
+                }
+                else if (type.symbol.flags & (32 /* Class */ | 64 /* Interface */)) {
+                    if (type.symbol.flags & 32 /* Class */) {
+                        resolveBaseTypesOfClass(type);
+                    }
+                    if (type.symbol.flags & 64 /* Interface */) {
+                        resolveBaseTypesOfInterface(type);
+                    }
+                }
+                else {
+                    ts.Debug.fail("type must be class or interface");
+                }
+            }
+            return type.resolvedBaseTypes;
+        }
+        function resolveBaseTypesOfClass(type) {
+            type.resolvedBaseTypes = ts.resolvingEmptyArray;
+            var baseConstructorType = getApparentType(getBaseConstructorTypeOfClass(type));
+            if (!(baseConstructorType.flags & (131072 /* Object */ | 524288 /* Intersection */ | 1 /* Any */))) {
+                return type.resolvedBaseTypes = ts.emptyArray;
+            }
+            var baseTypeNode = getBaseTypeNodeOfClass(type);
+            var typeArgs = typeArgumentsFromTypeReferenceNode(baseTypeNode);
+            var baseType;
+            var originalBaseType = baseConstructorType && baseConstructorType.symbol ? getDeclaredTypeOfSymbol(baseConstructorType.symbol) : undefined;
+            if (baseConstructorType.symbol && baseConstructorType.symbol.flags & 32 /* Class */ &&
+                areAllOuterTypeParametersApplied(originalBaseType)) {
+                // When base constructor type is a class with no captured type arguments we know that the constructors all have the same type parameters as the
+                // class and all return the instance type of the class. There is no need for further checks and we can apply the
+                // type arguments in the same manner as a type reference to get the same error reporting experience.
+                baseType = getTypeFromClassOrInterfaceReference(baseTypeNode, baseConstructorType.symbol, typeArgs);
+            }
+            else if (baseConstructorType.flags & 1 /* Any */) {
+                baseType = baseConstructorType;
+            }
+            else {
+                // The class derives from a "class-like" constructor function, check that we have at least one construct signature
+                // with a matching number of type parameters and use the return type of the first instantiated signature. Elsewhere
+                // we check that all instantiated signatures return the same type.
+                var constructors = getInstantiatedConstructorsForTypeArguments(baseConstructorType, baseTypeNode.typeArguments, baseTypeNode);
+                if (!constructors.length) {
+                    error(baseTypeNode.expression, ts.Diagnostics.No_base_constructor_has_the_specified_number_of_type_arguments);
+                    return type.resolvedBaseTypes = ts.emptyArray;
+                }
+                baseType = getReturnTypeOfSignature(constructors[0]);
+            }
+            if (baseType === errorType) {
+                return type.resolvedBaseTypes = ts.emptyArray;
+            }
+            if (!isValidBaseType(baseType)) {
+                error(baseTypeNode.expression, ts.Diagnostics.Base_constructor_return_type_0_is_not_a_class_or_interface_type, typeToString(baseType));
+                return type.resolvedBaseTypes = ts.emptyArray;
+            }
+            if (type === baseType || hasBaseType(baseType, type)) {
+                error(type.symbol.valueDeclaration, ts.Diagnostics.Type_0_recursively_references_itself_as_a_base_type, typeToString(type, /*enclosingDeclaration*/ undefined, 2 /* WriteArrayAsGenericType */));
+                return type.resolvedBaseTypes = ts.emptyArray;
+            }
+            if (type.resolvedBaseTypes === ts.resolvingEmptyArray) {
+                // Circular reference, likely through instantiation of default parameters
+                // (otherwise there'd be an error from hasBaseType) - this is fine, but `.members` should be reset
+                // as `getIndexedAccessType` via `instantiateType` via `getTypeFromClassOrInterfaceReference` forces a
+                // partial instantiation of the members without the base types fully resolved
+                type.members = undefined; // TODO: GH#18217
+            }
+            return type.resolvedBaseTypes = [baseType];
+        }
+        function areAllOuterTypeParametersApplied(type) {
+            // An unapplied type parameter has its symbol still the same as the matching argument symbol.
+            // Since parameters are applied outer-to-inner, only the last outer parameter needs to be checked.
+            var outerTypeParameters = type.outerTypeParameters;
+            if (outerTypeParameters) {
+                var last_1 = outerTypeParameters.length - 1;
+                var typeArguments = type.typeArguments;
+                return outerTypeParameters[last_1].symbol !== typeArguments[last_1].symbol;
+            }
+            return true;
+        }
+        // A valid base type is `any`, any non-generic object type or intersection of non-generic
+        // object types.
+        function isValidBaseType(type) {
+            return !!(type.flags & (131072 /* Object */ | 16777216 /* NonPrimitive */ | 1 /* Any */)) && !isGenericMappedType(type) ||
+                !!(type.flags & 524288 /* Intersection */) && ts.every(type.types, isValidBaseType);
+        }
+        function resolveBaseTypesOfInterface(type) {
+            type.resolvedBaseTypes = type.resolvedBaseTypes || ts.emptyArray;
+            for (var _i = 0, _a = type.symbol.declarations; _i < _a.length; _i++) {
+                var declaration = _a[_i];
+                if (declaration.kind === 236 /* InterfaceDeclaration */ && ts.getInterfaceBaseTypeNodes(declaration)) {
+                    for (var _b = 0, _c = ts.getInterfaceBaseTypeNodes(declaration); _b < _c.length; _b++) {
+                        var node = _c[_b];
+                        var baseType = getTypeFromTypeNode(node);
+                        if (baseType !== errorType) {
+                            if (isValidBaseType(baseType)) {
+                                if (type !== baseType && !hasBaseType(baseType, type)) {
+                                    if (type.resolvedBaseTypes === ts.emptyArray) {
+                                        type.resolvedBaseTypes = [baseType];
+                                    }
+                                    else {
+                                        type.resolvedBaseTypes.push(baseType);
+                                    }
+                                }
+                                else {
+                                    error(declaration, ts.Diagnostics.Type_0_recursively_references_itself_as_a_base_type, typeToString(type, /*enclosingDeclaration*/ undefined, 2 /* WriteArrayAsGenericType */));
+                                }
+                            }
+                            else {
+                                error(node, ts.Diagnostics.An_interface_may_only_extend_a_class_or_another_interface);
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        /**
+         * Returns true if the interface given by the symbol is free of "this" references.
+         *
+         * Specifically, the result is true if the interface itself contains no references
+         * to "this" in its body, if all base types are interfaces,
+         * and if none of the base interfaces have a "this" type.
+         */
+        function isThislessInterface(symbol) {
+            for (var _i = 0, _a = symbol.declarations; _i < _a.length; _i++) {
+                var declaration = _a[_i];
+                if (declaration.kind === 236 /* InterfaceDeclaration */) {
+                    if (declaration.flags & 64 /* ContainsThis */) {
+                        return false;
+                    }
+                    var baseTypeNodes = ts.getInterfaceBaseTypeNodes(declaration);
+                    if (baseTypeNodes) {
+                        for (var _b = 0, baseTypeNodes_1 = baseTypeNodes; _b < baseTypeNodes_1.length; _b++) {
+                            var node = baseTypeNodes_1[_b];
+                            if (ts.isEntityNameExpression(node.expression)) {
+                                var baseSymbol = resolveEntityName(node.expression, 67901928 /* Type */, /*ignoreErrors*/ true);
+                                if (!baseSymbol || !(baseSymbol.flags & 64 /* Interface */) || getDeclaredTypeOfClassOrInterface(baseSymbol).thisType) {
+                                    return false;
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+            return true;
+        }
+        function getDeclaredTypeOfClassOrInterface(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (!links.declaredType) {
+                var kind = symbol.flags & 32 /* Class */ ? 1 /* Class */ : 2 /* Interface */;
+                var type = links.declaredType = createObjectType(kind, symbol);
+                var outerTypeParameters = getOuterTypeParametersOfClassOrInterface(symbol);
+                var localTypeParameters = getLocalTypeParametersOfClassOrInterfaceOrTypeAlias(symbol);
+                // A class or interface is generic if it has type parameters or a "this" type. We always give classes a "this" type
+                // because it is not feasible to analyze all members to determine if the "this" type escapes the class (in particular,
+                // property types inferred from initializers and method return types inferred from return statements are very hard
+                // to exhaustively analyze). We give interfaces a "this" type if we can't definitely determine that they are free of
+                // "this" references.
+                if (outerTypeParameters || localTypeParameters || kind === 1 /* Class */ || !isThislessInterface(symbol)) {
+                    type.objectFlags |= 4 /* Reference */;
+                    type.typeParameters = ts.concatenate(outerTypeParameters, localTypeParameters);
+                    type.outerTypeParameters = outerTypeParameters;
+                    type.localTypeParameters = localTypeParameters;
+                    type.instantiations = ts.createMap();
+                    type.instantiations.set(getTypeListId(type.typeParameters), type);
+                    type.target = type;
+                    type.typeArguments = type.typeParameters;
+                    type.thisType = createType(65536 /* TypeParameter */);
+                    type.thisType.isThisType = true;
+                    type.thisType.symbol = symbol;
+                    type.thisType.constraint = type;
+                }
+            }
+            return links.declaredType;
+        }
+        function getDeclaredTypeOfTypeAlias(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (!links.declaredType) {
+                // Note that we use the links object as the target here because the symbol object is used as the unique
+                // identity for resolution of the 'type' property in SymbolLinks.
+                if (!pushTypeResolution(symbol, 2 /* DeclaredType */)) {
+                    return errorType;
+                }
+                var declaration = ts.find(symbol.declarations, function (d) {
+                    return ts.isJSDocTypeAlias(d) || d.kind === 237 /* TypeAliasDeclaration */;
+                });
+                var typeNode = ts.isJSDocTypeAlias(declaration) ? declaration.typeExpression : declaration.type;
+                // If typeNode is missing, we will error in checkJSDocTypedefTag.
+                var type = typeNode ? getTypeFromTypeNode(typeNode) : errorType;
+                if (popTypeResolution()) {
+                    var typeParameters = getLocalTypeParametersOfClassOrInterfaceOrTypeAlias(symbol);
+                    if (typeParameters) {
+                        // Initialize the instantiation cache for generic type aliases. The declared type corresponds to
+                        // an instantiation of the type alias with the type parameters supplied as type arguments.
+                        links.typeParameters = typeParameters;
+                        links.instantiations = ts.createMap();
+                        links.instantiations.set(getTypeListId(typeParameters), type);
+                    }
+                }
+                else {
+                    type = errorType;
+                    error(declaration.name, ts.Diagnostics.Type_alias_0_circularly_references_itself, symbolToString(symbol));
+                }
+                links.declaredType = type;
+            }
+            return links.declaredType;
+        }
+        function isStringConcatExpression(expr) {
+            if (expr.kind === 9 /* StringLiteral */) {
+                return true;
+            }
+            else if (expr.kind === 200 /* BinaryExpression */) {
+                return isStringConcatExpression(expr.left) && isStringConcatExpression(expr.right);
+            }
+            return false;
+        }
+        function isLiteralEnumMember(member) {
+            var expr = member.initializer;
+            if (!expr) {
+                return !(member.flags & 4194304 /* Ambient */);
+            }
+            switch (expr.kind) {
+                case 9 /* StringLiteral */:
+                case 8 /* NumericLiteral */:
+                    return true;
+                case 198 /* PrefixUnaryExpression */:
+                    return expr.operator === 38 /* MinusToken */ &&
+                        expr.operand.kind === 8 /* NumericLiteral */;
+                case 71 /* Identifier */:
+                    return ts.nodeIsMissing(expr) || !!getSymbolOfNode(member.parent).exports.get(expr.escapedText);
+                case 200 /* BinaryExpression */:
+                    return isStringConcatExpression(expr);
+                default:
+                    return false;
+            }
+        }
+        function getEnumKind(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (links.enumKind !== undefined) {
+                return links.enumKind;
+            }
+            var hasNonLiteralMember = false;
+            for (var _i = 0, _a = symbol.declarations; _i < _a.length; _i++) {
+                var declaration = _a[_i];
+                if (declaration.kind === 238 /* EnumDeclaration */) {
+                    for (var _b = 0, _c = declaration.members; _b < _c.length; _b++) {
+                        var member = _c[_b];
+                        if (member.initializer && member.initializer.kind === 9 /* StringLiteral */) {
+                            return links.enumKind = 1 /* Literal */;
+                        }
+                        if (!isLiteralEnumMember(member)) {
+                            hasNonLiteralMember = true;
+                        }
+                    }
+                }
+            }
+            return links.enumKind = hasNonLiteralMember ? 0 /* Numeric */ : 1 /* Literal */;
+        }
+        function getBaseTypeOfEnumLiteralType(type) {
+            return type.flags & 512 /* EnumLiteral */ && !(type.flags & 262144 /* Union */) ? getDeclaredTypeOfSymbol(getParentOfSymbol(type.symbol)) : type;
+        }
+        function getDeclaredTypeOfEnum(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (links.declaredType) {
+                return links.declaredType;
+            }
+            if (getEnumKind(symbol) === 1 /* Literal */) {
+                enumCount++;
+                var memberTypeList = [];
+                for (var _i = 0, _a = symbol.declarations; _i < _a.length; _i++) {
+                    var declaration = _a[_i];
+                    if (declaration.kind === 238 /* EnumDeclaration */) {
+                        for (var _b = 0, _c = declaration.members; _b < _c.length; _b++) {
+                            var member = _c[_b];
+                            var memberType = getLiteralType(getEnumMemberValue(member), enumCount, getSymbolOfNode(member)); // TODO: GH#18217
+                            getSymbolLinks(getSymbolOfNode(member)).declaredType = memberType;
+                            memberTypeList.push(memberType);
+                        }
+                    }
+                }
+                if (memberTypeList.length) {
+                    var enumType_1 = getUnionType(memberTypeList, 1 /* Literal */, symbol, /*aliasTypeArguments*/ undefined);
+                    if (enumType_1.flags & 262144 /* Union */) {
+                        enumType_1.flags |= 512 /* EnumLiteral */;
+                        enumType_1.symbol = symbol;
+                    }
+                    return links.declaredType = enumType_1;
+                }
+            }
+            var enumType = createType(32 /* Enum */);
+            enumType.symbol = symbol;
+            return links.declaredType = enumType;
+        }
+        function getDeclaredTypeOfEnumMember(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (!links.declaredType) {
+                var enumType = getDeclaredTypeOfEnum(getParentOfSymbol(symbol));
+                if (!links.declaredType) {
+                    links.declaredType = enumType;
+                }
+            }
+            return links.declaredType;
+        }
+        function getDeclaredTypeOfTypeParameter(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (!links.declaredType) {
+                var type = createType(65536 /* TypeParameter */);
+                type.symbol = symbol;
+                links.declaredType = type;
+            }
+            return links.declaredType;
+        }
+        function getDeclaredTypeOfAlias(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (!links.declaredType) {
+                links.declaredType = getDeclaredTypeOfSymbol(resolveAlias(symbol));
+            }
+            return links.declaredType;
+        }
+        function getDeclaredTypeOfSymbol(symbol) {
+            return tryGetDeclaredTypeOfSymbol(symbol) || errorType;
+        }
+        function tryGetDeclaredTypeOfSymbol(symbol) {
+            if (symbol.flags & (32 /* Class */ | 64 /* Interface */)) {
+                return getDeclaredTypeOfClassOrInterface(symbol);
+            }
+            if (symbol.flags & 524288 /* TypeAlias */) {
+                return getDeclaredTypeOfTypeAlias(symbol);
+            }
+            if (symbol.flags & 262144 /* TypeParameter */) {
+                return getDeclaredTypeOfTypeParameter(symbol);
+            }
+            if (symbol.flags & 384 /* Enum */) {
+                return getDeclaredTypeOfEnum(symbol);
+            }
+            if (symbol.flags & 8 /* EnumMember */) {
+                return getDeclaredTypeOfEnumMember(symbol);
+            }
+            if (symbol.flags & 2097152 /* Alias */) {
+                return getDeclaredTypeOfAlias(symbol);
+            }
+            return undefined;
+        }
+        /**
+         * A type is free of this references if it's the any, string, number, boolean, symbol, or void keyword, a string
+         * literal type, an array with an element type that is free of this references, or a type reference that is
+         * free of this references.
+         */
+        function isThislessType(node) {
+            switch (node.kind) {
+                case 119 /* AnyKeyword */:
+                case 142 /* UnknownKeyword */:
+                case 137 /* StringKeyword */:
+                case 134 /* NumberKeyword */:
+                case 122 /* BooleanKeyword */:
+                case 138 /* SymbolKeyword */:
+                case 135 /* ObjectKeyword */:
+                case 105 /* VoidKeyword */:
+                case 140 /* UndefinedKeyword */:
+                case 95 /* NullKeyword */:
+                case 131 /* NeverKeyword */:
+                case 178 /* LiteralType */:
+                    return true;
+                case 167 /* ArrayType */:
+                    return isThislessType(node.elementType);
+                case 162 /* TypeReference */:
+                    return !node.typeArguments || node.typeArguments.every(isThislessType);
+            }
+            return false;
+        }
+        /** A type parameter is thisless if its contraint is thisless, or if it has no constraint. */
+        function isThislessTypeParameter(node) {
+            return !node.constraint || isThislessType(node.constraint);
+        }
+        /**
+         * A variable-like declaration is free of this references if it has a type annotation
+         * that is thisless, or if it has no type annotation and no initializer (and is thus of type any).
+         */
+        function isThislessVariableLikeDeclaration(node) {
+            var typeNode = ts.getEffectiveTypeAnnotationNode(node);
+            return typeNode ? isThislessType(typeNode) : !ts.hasInitializer(node);
+        }
+        /**
+         * A function-like declaration is considered free of `this` references if it has a return type
+         * annotation that is free of this references and if each parameter is thisless and if
+         * each type parameter (if present) is thisless.
+         */
+        function isThislessFunctionLikeDeclaration(node) {
+            var returnType = ts.getEffectiveReturnTypeNode(node);
+            var typeParameters = ts.getEffectiveTypeParameterDeclarations(node);
+            return (node.kind === 155 /* Constructor */ || (!!returnType && isThislessType(returnType))) &&
+                node.parameters.every(isThislessVariableLikeDeclaration) &&
+                typeParameters.every(isThislessTypeParameter);
+        }
+        /**
+         * Returns true if the class or interface member given by the symbol is free of "this" references. The
+         * function may return false for symbols that are actually free of "this" references because it is not
+         * feasible to perform a complete analysis in all cases. In particular, property members with types
+         * inferred from their initializers and function members with inferred return types are conservatively
+         * assumed not to be free of "this" references.
+         */
+        function isThisless(symbol) {
+            if (symbol.declarations && symbol.declarations.length === 1) {
+                var declaration = symbol.declarations[0];
+                if (declaration) {
+                    switch (declaration.kind) {
+                        case 152 /* PropertyDeclaration */:
+                        case 151 /* PropertySignature */:
+                            return isThislessVariableLikeDeclaration(declaration);
+                        case 154 /* MethodDeclaration */:
+                        case 153 /* MethodSignature */:
+                        case 155 /* Constructor */:
+                            return isThislessFunctionLikeDeclaration(declaration);
+                    }
+                }
+            }
+            return false;
+        }
+        // The mappingThisOnly flag indicates that the only type parameter being mapped is "this". When the flag is true,
+        // we check symbols to see if we can quickly conclude they are free of "this" references, thus needing no instantiation.
+        function createInstantiatedSymbolTable(symbols, mapper, mappingThisOnly) {
+            var result = ts.createSymbolTable();
+            for (var _i = 0, symbols_2 = symbols; _i < symbols_2.length; _i++) {
+                var symbol = symbols_2[_i];
+                result.set(symbol.escapedName, mappingThisOnly && isThisless(symbol) ? symbol : instantiateSymbol(symbol, mapper));
+            }
+            return result;
+        }
+        function addInheritedMembers(symbols, baseSymbols) {
+            for (var _i = 0, baseSymbols_1 = baseSymbols; _i < baseSymbols_1.length; _i++) {
+                var s = baseSymbols_1[_i];
+                if (!symbols.has(s.escapedName)) {
+                    symbols.set(s.escapedName, s);
+                }
+            }
+        }
+        function resolveDeclaredMembers(type) {
+            if (!type.declaredProperties) {
+                var symbol = type.symbol;
+                var members = getMembersOfSymbol(symbol);
+                type.declaredProperties = getNamedMembers(members);
+                // Start with signatures at empty array in case of recursive types
+                type.declaredCallSignatures = ts.emptyArray;
+                type.declaredConstructSignatures = ts.emptyArray;
+                type.declaredCallSignatures = getSignaturesOfSymbol(members.get("__call" /* Call */));
+                type.declaredConstructSignatures = getSignaturesOfSymbol(members.get("__new" /* New */));
+                type.declaredStringIndexInfo = getIndexInfoOfSymbol(symbol, 0 /* String */);
+                type.declaredNumberIndexInfo = getIndexInfoOfSymbol(symbol, 1 /* Number */);
+            }
+            return type;
+        }
+        /**
+         * Indicates whether a type can be used as a late-bound name.
+         */
+        function isTypeUsableAsLateBoundName(type) {
+            return !!(type.flags & 2240 /* StringOrNumberLiteralOrUnique */);
+        }
+        /**
+         * Indicates whether a declaration name is definitely late-bindable.
+         * A declaration name is only late-bindable if:
+         * - It is a `ComputedPropertyName`.
+         * - Its expression is an `Identifier` or either a `PropertyAccessExpression` an
+         * `ElementAccessExpression` consisting only of these same three types of nodes.
+         * - The type of its expression is a string or numeric literal type, or is a `unique symbol` type.
+         */
+        function isLateBindableName(node) {
+            return ts.isComputedPropertyName(node)
+                && ts.isEntityNameExpression(node.expression)
+                && isTypeUsableAsLateBoundName(checkComputedPropertyName(node));
+        }
+        /**
+         * Indicates whether a declaration has a late-bindable dynamic name.
+         */
+        function hasLateBindableName(node) {
+            var name = ts.getNameOfDeclaration(node);
+            return !!name && isLateBindableName(name);
+        }
+        /**
+         * Indicates whether a declaration has a dynamic name that cannot be late-bound.
+         */
+        function hasNonBindableDynamicName(node) {
+            return ts.hasDynamicName(node) && !hasLateBindableName(node);
+        }
+        /**
+         * Indicates whether a declaration name is a dynamic name that cannot be late-bound.
+         */
+        function isNonBindableDynamicName(node) {
+            return ts.isDynamicName(node) && !isLateBindableName(node);
+        }
+        /**
+         * Gets the symbolic name for a late-bound member from its type.
+         */
+        function getLateBoundNameFromType(type) {
+            if (type.flags & 2048 /* UniqueESSymbol */) {
+                return "__@" + type.symbol.escapedName + "@" + getSymbolId(type.symbol);
+            }
+            if (type.flags & 192 /* StringOrNumberLiteral */) {
+                return ts.escapeLeadingUnderscores("" + type.value);
+            }
+            return ts.Debug.fail();
+        }
+        /**
+         * Adds a declaration to a late-bound dynamic member. This performs the same function for
+         * late-bound members that `addDeclarationToSymbol` in binder.ts performs for early-bound
+         * members.
+         */
+        function addDeclarationToLateBoundSymbol(symbol, member, symbolFlags) {
+            ts.Debug.assert(!!(ts.getCheckFlags(symbol) & 1024 /* Late */), "Expected a late-bound symbol.");
+            symbol.flags |= symbolFlags;
+            getSymbolLinks(member.symbol).lateSymbol = symbol;
+            if (!symbol.declarations) {
+                symbol.declarations = [member];
+            }
+            else {
+                symbol.declarations.push(member);
+            }
+            if (symbolFlags & 67216319 /* Value */) {
+                if (!symbol.valueDeclaration || symbol.valueDeclaration.kind !== member.kind) {
+                    symbol.valueDeclaration = member;
+                }
+            }
+        }
+        /**
+         * Performs late-binding of a dynamic member. This performs the same function for
+         * late-bound members that `declareSymbol` in binder.ts performs for early-bound
+         * members.
+         *
+         * If a symbol is a dynamic name from a computed property, we perform an additional "late"
+         * binding phase to attempt to resolve the name for the symbol from the type of the computed
+         * property's expression. If the type of the expression is a string-literal, numeric-literal,
+         * or unique symbol type, we can use that type as the name of the symbol.
+         *
+         * For example, given:
+         *
+         *   const x = Symbol();
+         *
+         *   interface I {
+         *     [x]: number;
+         *   }
+         *
+         * The binder gives the property `[x]: number` a special symbol with the name "__computed".
+         * In the late-binding phase we can type-check the expression `x` and see that it has a
+         * unique symbol type which we can then use as the name of the member. This allows users
+         * to define custom symbols that can be used in the members of an object type.
+         *
+         * @param parent The containing symbol for the member.
+         * @param earlySymbols The early-bound symbols of the parent.
+         * @param lateSymbols The late-bound symbols of the parent.
+         * @param decl The member to bind.
+         */
+        function lateBindMember(parent, earlySymbols, lateSymbols, decl) {
+            ts.Debug.assert(!!decl.symbol, "The member is expected to have a symbol.");
+            var links = getNodeLinks(decl);
+            if (!links.resolvedSymbol) {
+                // In the event we attempt to resolve the late-bound name of this member recursively,
+                // fall back to the early-bound name of this member.
+                links.resolvedSymbol = decl.symbol;
+                var type = checkComputedPropertyName(decl.name);
+                if (isTypeUsableAsLateBoundName(type)) {
+                    var memberName = getLateBoundNameFromType(type);
+                    var symbolFlags = decl.symbol.flags;
+                    // Get or add a late-bound symbol for the member. This allows us to merge late-bound accessor declarations.
+                    var lateSymbol = lateSymbols.get(memberName);
+                    if (!lateSymbol)
+                        lateSymbols.set(memberName, lateSymbol = createSymbol(0 /* None */, memberName, 1024 /* Late */));
+                    // Report an error if a late-bound member has the same name as an early-bound member,
+                    // or if we have another early-bound symbol declaration with the same name and
+                    // conflicting flags.
+                    var earlySymbol = earlySymbols && earlySymbols.get(memberName);
+                    if (lateSymbol.flags & getExcludedSymbolFlags(symbolFlags) || earlySymbol) {
+                        // If we have an existing early-bound member, combine its declarations so that we can
+                        // report an error at each declaration.
+                        var declarations = earlySymbol ? ts.concatenate(earlySymbol.declarations, lateSymbol.declarations) : lateSymbol.declarations;
+                        var name_2 = ts.declarationNameToString(decl.name);
+                        ts.forEach(declarations, function (declaration) { return error(ts.getNameOfDeclaration(declaration) || declaration, ts.Diagnostics.Duplicate_declaration_0, name_2); });
+                        error(decl.name || decl, ts.Diagnostics.Duplicate_declaration_0, name_2);
+                        lateSymbol = createSymbol(0 /* None */, memberName, 1024 /* Late */);
+                    }
+                    lateSymbol.nameType = type;
+                    addDeclarationToLateBoundSymbol(lateSymbol, decl, symbolFlags);
+                    if (lateSymbol.parent) {
+                        ts.Debug.assert(lateSymbol.parent === parent, "Existing symbol parent should match new one");
+                    }
+                    else {
+                        lateSymbol.parent = parent;
+                    }
+                    return links.resolvedSymbol = lateSymbol;
+                }
+            }
+            return links.resolvedSymbol;
+        }
+        function getResolvedMembersOrExportsOfSymbol(symbol, resolutionKind) {
+            var links = getSymbolLinks(symbol);
+            if (!links[resolutionKind]) {
+                var isStatic = resolutionKind === "resolvedExports" /* resolvedExports */;
+                var earlySymbols = !isStatic ? symbol.members :
+                    symbol.flags & 1536 /* Module */ ? getExportsOfModuleWorker(symbol) :
+                        symbol.exports;
+                // In the event we recursively resolve the members/exports of the symbol, we
+                // set the initial value of resolvedMembers/resolvedExports to the early-bound
+                // members/exports of the symbol.
+                links[resolutionKind] = earlySymbols || emptySymbols;
+                // fill in any as-yet-unresolved late-bound members.
+                var lateSymbols = ts.createSymbolTable();
+                for (var _i = 0, _a = symbol.declarations; _i < _a.length; _i++) {
+                    var decl = _a[_i];
+                    var members = ts.getMembersOfDeclaration(decl);
+                    if (members) {
+                        for (var _b = 0, members_4 = members; _b < members_4.length; _b++) {
+                            var member = members_4[_b];
+                            if (isStatic === ts.hasStaticModifier(member) && hasLateBindableName(member)) {
+                                lateBindMember(symbol, earlySymbols, lateSymbols, member);
+                            }
+                        }
+                    }
+                }
+                links[resolutionKind] = combineSymbolTables(earlySymbols, lateSymbols) || emptySymbols;
+            }
+            return links[resolutionKind];
+        }
+        /**
+         * Gets a SymbolTable containing both the early- and late-bound members of a symbol.
+         *
+         * For a description of late-binding, see `lateBindMember`.
+         */
+        function getMembersOfSymbol(symbol) {
+            return symbol.flags & 6240 /* LateBindingContainer */
+                ? getResolvedMembersOrExportsOfSymbol(symbol, "resolvedMembers" /* resolvedMembers */)
+                : symbol.members || emptySymbols;
+        }
+        /**
+         * If a symbol is the dynamic name of the member of an object type, get the late-bound
+         * symbol of the member.
+         *
+         * For a description of late-binding, see `lateBindMember`.
+         */
+        function getLateBoundSymbol(symbol) {
+            if (symbol.flags & 106500 /* ClassMember */ && symbol.escapedName === "__computed" /* Computed */) {
+                var links = getSymbolLinks(symbol);
+                if (!links.lateSymbol && ts.some(symbol.declarations, hasLateBindableName)) {
+                    // force late binding of members/exports. This will set the late-bound symbol
+                    if (ts.some(symbol.declarations, ts.hasStaticModifier)) {
+                        getExportsOfSymbol(symbol.parent);
+                    }
+                    else {
+                        getMembersOfSymbol(symbol.parent);
+                    }
+                }
+                return links.lateSymbol || (links.lateSymbol = symbol);
+            }
+            return symbol;
+        }
+        function getTypeWithThisArgument(type, thisArgument, needApparentType) {
+            if (ts.getObjectFlags(type) & 4 /* Reference */) {
+                var target = type.target;
+                var typeArguments = type.typeArguments;
+                if (ts.length(target.typeParameters) === ts.length(typeArguments)) {
+                    var ref = createTypeReference(target, ts.concatenate(typeArguments, [thisArgument || target.thisType]));
+                    return needApparentType ? getApparentType(ref) : ref;
+                }
+            }
+            else if (type.flags & 524288 /* Intersection */) {
+                return getIntersectionType(ts.map(type.types, function (t) { return getTypeWithThisArgument(t, thisArgument, needApparentType); }));
+            }
+            return needApparentType ? getApparentType(type) : type;
+        }
+        function resolveObjectTypeMembers(type, source, typeParameters, typeArguments) {
+            var mapper;
+            var members;
+            var callSignatures;
+            var constructSignatures;
+            var stringIndexInfo;
+            var numberIndexInfo;
+            if (ts.rangeEquals(typeParameters, typeArguments, 0, typeParameters.length)) {
+                mapper = identityMapper;
+                members = source.symbol ? getMembersOfSymbol(source.symbol) : ts.createSymbolTable(source.declaredProperties);
+                callSignatures = source.declaredCallSignatures;
+                constructSignatures = source.declaredConstructSignatures;
+                stringIndexInfo = source.declaredStringIndexInfo;
+                numberIndexInfo = source.declaredNumberIndexInfo;
+            }
+            else {
+                mapper = createTypeMapper(typeParameters, typeArguments);
+                members = createInstantiatedSymbolTable(source.declaredProperties, mapper, /*mappingThisOnly*/ typeParameters.length === 1);
+                callSignatures = instantiateSignatures(source.declaredCallSignatures, mapper);
+                constructSignatures = instantiateSignatures(source.declaredConstructSignatures, mapper);
+                stringIndexInfo = instantiateIndexInfo(source.declaredStringIndexInfo, mapper);
+                numberIndexInfo = instantiateIndexInfo(source.declaredNumberIndexInfo, mapper);
+            }
+            var baseTypes = getBaseTypes(source);
+            if (baseTypes.length) {
+                if (source.symbol && members === getMembersOfSymbol(source.symbol)) {
+                    members = ts.createSymbolTable(source.declaredProperties);
+                }
+                setStructuredTypeMembers(type, members, callSignatures, constructSignatures, stringIndexInfo, numberIndexInfo);
+                var thisArgument = ts.lastOrUndefined(typeArguments);
+                for (var _i = 0, baseTypes_1 = baseTypes; _i < baseTypes_1.length; _i++) {
+                    var baseType = baseTypes_1[_i];
+                    var instantiatedBaseType = thisArgument ? getTypeWithThisArgument(instantiateType(baseType, mapper), thisArgument) : baseType;
+                    addInheritedMembers(members, getPropertiesOfType(instantiatedBaseType));
+                    callSignatures = ts.concatenate(callSignatures, getSignaturesOfType(instantiatedBaseType, 0 /* Call */));
+                    constructSignatures = ts.concatenate(constructSignatures, getSignaturesOfType(instantiatedBaseType, 1 /* Construct */));
+                    if (!stringIndexInfo) {
+                        stringIndexInfo = instantiatedBaseType === anyType ?
+                            createIndexInfo(anyType, /*isReadonly*/ false) :
+                            getIndexInfoOfType(instantiatedBaseType, 0 /* String */);
+                    }
+                    numberIndexInfo = numberIndexInfo || getIndexInfoOfType(instantiatedBaseType, 1 /* Number */);
+                }
+            }
+            setStructuredTypeMembers(type, members, callSignatures, constructSignatures, stringIndexInfo, numberIndexInfo);
+        }
+        function resolveClassOrInterfaceMembers(type) {
+            resolveObjectTypeMembers(type, resolveDeclaredMembers(type), ts.emptyArray, ts.emptyArray);
+        }
+        function resolveTypeReferenceMembers(type) {
+            var source = resolveDeclaredMembers(type.target);
+            var typeParameters = ts.concatenate(source.typeParameters, [source.thisType]);
+            var typeArguments = type.typeArguments && type.typeArguments.length === typeParameters.length ?
+                type.typeArguments : ts.concatenate(type.typeArguments, [type]);
+            resolveObjectTypeMembers(type, source, typeParameters, typeArguments);
+        }
+        function createSignature(declaration, typeParameters, thisParameter, parameters, resolvedReturnType, resolvedTypePredicate, minArgumentCount, hasRestParameter, hasLiteralTypes) {
+            var sig = new Signature(checker);
+            sig.declaration = declaration;
+            sig.typeParameters = typeParameters;
+            sig.parameters = parameters;
+            sig.thisParameter = thisParameter;
+            sig.resolvedReturnType = resolvedReturnType;
+            sig.resolvedTypePredicate = resolvedTypePredicate;
+            sig.minArgumentCount = minArgumentCount;
+            sig.hasRestParameter = hasRestParameter;
+            sig.hasLiteralTypes = hasLiteralTypes;
+            sig.target = undefined;
+            sig.mapper = undefined;
+            return sig;
+        }
+        function cloneSignature(sig) {
+            return createSignature(sig.declaration, sig.typeParameters, sig.thisParameter, sig.parameters, /*resolvedReturnType*/ undefined, 
+            /*resolvedTypePredicate*/ undefined, sig.minArgumentCount, sig.hasRestParameter, sig.hasLiteralTypes);
+        }
+        function getDefaultConstructSignatures(classType) {
+            var baseConstructorType = getBaseConstructorTypeOfClass(classType);
+            var baseSignatures = getSignaturesOfType(baseConstructorType, 1 /* Construct */);
+            if (baseSignatures.length === 0) {
+                return [createSignature(undefined, classType.localTypeParameters, undefined, ts.emptyArray, classType, /*resolvedTypePredicate*/ undefined, 0, /*hasRestParameter*/ false, /*hasLiteralTypes*/ false)]; // TODO: GH#18217
+            }
+            var baseTypeNode = getBaseTypeNodeOfClass(classType);
+            var isJavaScript = ts.isInJavaScriptFile(baseTypeNode);
+            var typeArguments = typeArgumentsFromTypeReferenceNode(baseTypeNode);
+            var typeArgCount = ts.length(typeArguments);
+            var result = [];
+            for (var _i = 0, baseSignatures_1 = baseSignatures; _i < baseSignatures_1.length; _i++) {
+                var baseSig = baseSignatures_1[_i];
+                var minTypeArgumentCount = getMinTypeArgumentCount(baseSig.typeParameters);
+                var typeParamCount = ts.length(baseSig.typeParameters);
+                if (isJavaScript || typeArgCount >= minTypeArgumentCount && typeArgCount <= typeParamCount) {
+                    var sig = typeParamCount ? createSignatureInstantiation(baseSig, fillMissingTypeArguments(typeArguments, baseSig.typeParameters, minTypeArgumentCount, isJavaScript)) : cloneSignature(baseSig);
+                    sig.typeParameters = classType.localTypeParameters;
+                    sig.resolvedReturnType = classType;
+                    result.push(sig);
+                }
+            }
+            return result;
+        }
+        function findMatchingSignature(signatureList, signature, partialMatch, ignoreThisTypes, ignoreReturnTypes) {
+            for (var _i = 0, signatureList_1 = signatureList; _i < signatureList_1.length; _i++) {
+                var s = signatureList_1[_i];
+                if (compareSignaturesIdentical(s, signature, partialMatch, ignoreThisTypes, ignoreReturnTypes, compareTypesIdentical)) {
+                    return s;
+                }
+            }
+        }
+        function findMatchingSignatures(signatureLists, signature, listIndex) {
+            if (signature.typeParameters) {
+                // We require an exact match for generic signatures, so we only return signatures from the first
+                // signature list and only if they have exact matches in the other signature lists.
+                if (listIndex > 0) {
+                    return undefined;
+                }
+                for (var i = 1; i < signatureLists.length; i++) {
+                    if (!findMatchingSignature(signatureLists[i], signature, /*partialMatch*/ false, /*ignoreThisTypes*/ false, /*ignoreReturnTypes*/ false)) {
+                        return undefined;
+                    }
+                }
+                return [signature];
+            }
+            var result;
+            for (var i = 0; i < signatureLists.length; i++) {
+                // Allow matching non-generic signatures to have excess parameters and different return types
+                var match = i === listIndex ? signature : findMatchingSignature(signatureLists[i], signature, /*partialMatch*/ true, /*ignoreThisTypes*/ true, /*ignoreReturnTypes*/ true);
+                if (!match) {
+                    return undefined;
+                }
+                result = ts.appendIfUnique(result, match);
+            }
+            return result;
+        }
+        // The signatures of a union type are those signatures that are present in each of the constituent types.
+        // Generic signatures must match exactly, but non-generic signatures are allowed to have extra optional
+        // parameters and may differ in return types. When signatures differ in return types, the resulting return
+        // type is the union of the constituent return types.
+        function getUnionSignatures(types, kind) {
+            var signatureLists = ts.map(types, function (t) { return getSignaturesOfType(t, kind); });
+            var result;
+            for (var i = 0; i < signatureLists.length; i++) {
+                for (var _i = 0, _a = signatureLists[i]; _i < _a.length; _i++) {
+                    var signature = _a[_i];
+                    // Only process signatures with parameter lists that aren't already in the result list
+                    if (!result || !findMatchingSignature(result, signature, /*partialMatch*/ false, /*ignoreThisTypes*/ true, /*ignoreReturnTypes*/ true)) {
+                        var unionSignatures = findMatchingSignatures(signatureLists, signature, i);
+                        if (unionSignatures) {
+                            var s = signature;
+                            // Union the result types when more than one signature matches
+                            if (unionSignatures.length > 1) {
+                                var thisParameter = signature.thisParameter;
+                                if (ts.forEach(unionSignatures, function (sig) { return sig.thisParameter; })) {
+                                    // TODO: GH#18217 We tested that *some* has thisParameter and now act as if *all* do
+                                    var thisType = getUnionType(ts.map(unionSignatures, function (sig) { return sig.thisParameter ? getTypeOfSymbol(sig.thisParameter) : anyType; }), 2 /* Subtype */);
+                                    thisParameter = createSymbolWithType(signature.thisParameter, thisType);
+                                }
+                                s = cloneSignature(signature);
+                                s.thisParameter = thisParameter;
+                                s.unionSignatures = unionSignatures;
+                            }
+                            (result || (result = [])).push(s);
+                        }
+                    }
+                }
+            }
+            return result || ts.emptyArray;
+        }
+        function getUnionIndexInfo(types, kind) {
+            var indexTypes = [];
+            var isAnyReadonly = false;
+            for (var _i = 0, types_2 = types; _i < types_2.length; _i++) {
+                var type = types_2[_i];
+                var indexInfo = getIndexInfoOfType(type, kind);
+                if (!indexInfo) {
+                    return undefined;
+                }
+                indexTypes.push(indexInfo.type);
+                isAnyReadonly = isAnyReadonly || indexInfo.isReadonly;
+            }
+            return createIndexInfo(getUnionType(indexTypes, 2 /* Subtype */), isAnyReadonly);
+        }
+        function resolveUnionTypeMembers(type) {
+            // The members and properties collections are empty for union types. To get all properties of a union
+            // type use getPropertiesOfType (only the language service uses this).
+            var callSignatures = getUnionSignatures(type.types, 0 /* Call */);
+            var constructSignatures = getUnionSignatures(type.types, 1 /* Construct */);
+            var stringIndexInfo = getUnionIndexInfo(type.types, 0 /* String */);
+            var numberIndexInfo = getUnionIndexInfo(type.types, 1 /* Number */);
+            setStructuredTypeMembers(type, emptySymbols, callSignatures, constructSignatures, stringIndexInfo, numberIndexInfo);
+        }
+        function intersectTypes(type1, type2) {
+            return !type1 ? type2 : !type2 ? type1 : getIntersectionType([type1, type2]);
+        }
+        function intersectIndexInfos(info1, info2) {
+            return !info1 ? info2 : !info2 ? info1 : createIndexInfo(getIntersectionType([info1.type, info2.type]), info1.isReadonly && info2.isReadonly);
+        }
+        function unionSpreadIndexInfos(info1, info2) {
+            return info1 && info2 && createIndexInfo(getUnionType([info1.type, info2.type]), info1.isReadonly || info2.isReadonly);
+        }
+        function includeMixinType(type, types, index) {
+            var mixedTypes = [];
+            for (var i = 0; i < types.length; i++) {
+                if (i === index) {
+                    mixedTypes.push(type);
+                }
+                else if (isMixinConstructorType(types[i])) {
+                    mixedTypes.push(getReturnTypeOfSignature(getSignaturesOfType(types[i], 1 /* Construct */)[0]));
+                }
+            }
+            return getIntersectionType(mixedTypes);
+        }
+        function resolveIntersectionTypeMembers(type) {
+            // The members and properties collections are empty for intersection types. To get all properties of an
+            // intersection type use getPropertiesOfType (only the language service uses this).
+            var callSignatures = ts.emptyArray;
+            var constructSignatures = ts.emptyArray;
+            var stringIndexInfo;
+            var numberIndexInfo;
+            var types = type.types;
+            var mixinCount = ts.countWhere(types, isMixinConstructorType);
+            var _loop_5 = function (i) {
+                var t = type.types[i];
+                // When an intersection type contains mixin constructor types, the construct signatures from
+                // those types are discarded and their return types are mixed into the return types of all
+                // other construct signatures in the intersection type. For example, the intersection type
+                // '{ new(...args: any[]) => A } & { new(s: string) => B }' has a single construct signature
+                // 'new(s: string) => A & B'.
+                if (mixinCount === 0 || mixinCount === types.length && i === 0 || !isMixinConstructorType(t)) {
+                    var signatures = getSignaturesOfType(t, 1 /* Construct */);
+                    if (signatures.length && mixinCount > 0) {
+                        signatures = ts.map(signatures, function (s) {
+                            var clone = cloneSignature(s);
+                            clone.resolvedReturnType = includeMixinType(getReturnTypeOfSignature(s), types, i);
+                            return clone;
+                        });
+                    }
+                    constructSignatures = ts.concatenate(constructSignatures, signatures);
+                }
+                callSignatures = ts.concatenate(callSignatures, getSignaturesOfType(t, 0 /* Call */));
+                stringIndexInfo = intersectIndexInfos(stringIndexInfo, getIndexInfoOfType(t, 0 /* String */));
+                numberIndexInfo = intersectIndexInfos(numberIndexInfo, getIndexInfoOfType(t, 1 /* Number */));
+            };
+            for (var i = 0; i < types.length; i++) {
+                _loop_5(i);
+            }
+            setStructuredTypeMembers(type, emptySymbols, callSignatures, constructSignatures, stringIndexInfo, numberIndexInfo);
+        }
+        /**
+         * Converts an AnonymousType to a ResolvedType.
+         */
+        function resolveAnonymousTypeMembers(type) {
+            var symbol = type.symbol;
+            if (type.target) {
+                var members = createInstantiatedSymbolTable(getPropertiesOfObjectType(type.target), type.mapper, /*mappingThisOnly*/ false);
+                var callSignatures = instantiateSignatures(getSignaturesOfType(type.target, 0 /* Call */), type.mapper);
+                var constructSignatures = instantiateSignatures(getSignaturesOfType(type.target, 1 /* Construct */), type.mapper);
+                var stringIndexInfo = instantiateIndexInfo(getIndexInfoOfType(type.target, 0 /* String */), type.mapper);
+                var numberIndexInfo = instantiateIndexInfo(getIndexInfoOfType(type.target, 1 /* Number */), type.mapper);
+                setStructuredTypeMembers(type, members, callSignatures, constructSignatures, stringIndexInfo, numberIndexInfo);
+            }
+            else if (symbol.flags & 2048 /* TypeLiteral */) {
+                var members = getMembersOfSymbol(symbol);
+                var callSignatures = getSignaturesOfSymbol(members.get("__call" /* Call */));
+                var constructSignatures = getSignaturesOfSymbol(members.get("__new" /* New */));
+                var stringIndexInfo = getIndexInfoOfSymbol(symbol, 0 /* String */);
+                var numberIndexInfo = getIndexInfoOfSymbol(symbol, 1 /* Number */);
+                setStructuredTypeMembers(type, members, callSignatures, constructSignatures, stringIndexInfo, numberIndexInfo);
+            }
+            else {
+                // Combinations of function, class, enum and module
+                var members = emptySymbols;
+                var stringIndexInfo = void 0;
+                if (symbol.exports) {
+                    members = getExportsOfSymbol(symbol);
+                }
+                setStructuredTypeMembers(type, members, ts.emptyArray, ts.emptyArray, undefined, undefined);
+                if (symbol.flags & 32 /* Class */) {
+                    var classType = getDeclaredTypeOfClassOrInterface(symbol);
+                    var baseConstructorType = getBaseConstructorTypeOfClass(classType);
+                    if (baseConstructorType.flags & (131072 /* Object */ | 524288 /* Intersection */ | 2162688 /* TypeVariable */)) {
+                        members = ts.createSymbolTable(getNamedMembers(members));
+                        addInheritedMembers(members, getPropertiesOfType(baseConstructorType));
+                    }
+                    else if (baseConstructorType === anyType) {
+                        stringIndexInfo = createIndexInfo(anyType, /*isReadonly*/ false);
+                    }
+                }
+                var numberIndexInfo = symbol.flags & 384 /* Enum */ ? enumNumberIndexInfo : undefined;
+                setStructuredTypeMembers(type, members, ts.emptyArray, ts.emptyArray, stringIndexInfo, numberIndexInfo);
+                // We resolve the members before computing the signatures because a signature may use
+                // typeof with a qualified name expression that circularly references the type we are
+                // in the process of resolving (see issue #6072). The temporarily empty signature list
+                // will never be observed because a qualified name can't reference signatures.
+                if (symbol.flags & (16 /* Function */ | 8192 /* Method */)) {
+                    type.callSignatures = getSignaturesOfSymbol(symbol);
+                }
+                // And likewise for construct signatures for classes
+                if (symbol.flags & 32 /* Class */) {
+                    var classType = getDeclaredTypeOfClassOrInterface(symbol);
+                    var constructSignatures = getSignaturesOfSymbol(symbol.members.get("__constructor" /* Constructor */));
+                    if (!constructSignatures.length) {
+                        constructSignatures = getDefaultConstructSignatures(classType);
+                    }
+                    type.constructSignatures = constructSignatures;
+                }
+            }
+        }
+        function resolveReverseMappedTypeMembers(type) {
+            var indexInfo = getIndexInfoOfType(type.source, 0 /* String */);
+            var modifiers = getMappedTypeModifiers(type.mappedType);
+            var readonlyMask = modifiers & 1 /* IncludeReadonly */ ? false : true;
+            var optionalMask = modifiers & 4 /* IncludeOptional */ ? 0 : 16777216 /* Optional */;
+            var stringIndexInfo = indexInfo && createIndexInfo(inferReverseMappedType(indexInfo.type, type.mappedType), readonlyMask && indexInfo.isReadonly);
+            var members = ts.createSymbolTable();
+            for (var _i = 0, _a = getPropertiesOfType(type.source); _i < _a.length; _i++) {
+                var prop = _a[_i];
+                var checkFlags = 2048 /* ReverseMapped */ | (readonlyMask && isReadonlySymbol(prop) ? 8 /* Readonly */ : 0);
+                var inferredProp = createSymbol(4 /* Property */ | prop.flags & optionalMask, prop.escapedName, checkFlags);
+                inferredProp.declarations = prop.declarations;
+                inferredProp.nameType = prop.nameType;
+                inferredProp.propertyType = getTypeOfSymbol(prop);
+                inferredProp.mappedType = type.mappedType;
+                members.set(prop.escapedName, inferredProp);
+            }
+            setStructuredTypeMembers(type, members, ts.emptyArray, ts.emptyArray, stringIndexInfo, undefined);
+        }
+        /** Resolve the members of a mapped type { [P in K]: T } */
+        function resolveMappedTypeMembers(type) {
+            var members = ts.createSymbolTable();
+            var stringIndexInfo;
+            var numberIndexInfo;
+            // Resolve upfront such that recursive references see an empty object type.
+            setStructuredTypeMembers(type, emptySymbols, ts.emptyArray, ts.emptyArray, undefined, undefined);
+            // In { [P in K]: T }, we refer to P as the type parameter type, K as the constraint type,
+            // and T as the template type.
+            var typeParameter = getTypeParameterFromMappedType(type);
+            var constraintType = getConstraintTypeFromMappedType(type);
+            var templateType = getTemplateTypeFromMappedType(type.target || type);
+            var modifiersType = getApparentType(getModifiersTypeFromMappedType(type)); // The 'T' in 'keyof T'
+            var templateModifiers = getMappedTypeModifiers(type);
+            var include = keyofStringsOnly ? 64 /* StringLiteral */ : 2240 /* StringOrNumberLiteralOrUnique */;
+            if (isMappedTypeWithKeyofConstraintDeclaration(type)) {
+                // We have a { [P in keyof T]: X }
+                for (var _i = 0, _a = getPropertiesOfType(modifiersType); _i < _a.length; _i++) {
+                    var prop = _a[_i];
+                    addMemberForKeyType(getLiteralTypeFromPropertyName(prop, include), /*_index*/ undefined, prop);
+                }
+                if (modifiersType.flags & 1 /* Any */ || getIndexInfoOfType(modifiersType, 0 /* String */)) {
+                    addMemberForKeyType(stringType);
+                }
+                if (!keyofStringsOnly && getIndexInfoOfType(modifiersType, 1 /* Number */)) {
+                    addMemberForKeyType(numberType);
+                }
+            }
+            else {
+                // First, if the constraint type is a type parameter, obtain the base constraint. Then,
+                // if the key type is a 'keyof X', obtain 'keyof C' where C is the base constraint of X.
+                // Finally, iterate over the constituents of the resulting iteration type.
+                var keyType = constraintType.flags & 14745600 /* InstantiableNonPrimitive */ ? getApparentType(constraintType) : constraintType;
+                var iterationType = keyType.flags & 1048576 /* Index */ ? getIndexType(getApparentType(keyType.type)) : keyType;
+                forEachType(iterationType, addMemberForKeyType);
+            }
+            setStructuredTypeMembers(type, members, ts.emptyArray, ts.emptyArray, stringIndexInfo, numberIndexInfo);
+            function addMemberForKeyType(t, _index, origin) {
+                // Create a mapper from T to the current iteration type constituent. Then, if the
+                // mapped type is itself an instantiated type, combine the iteration mapper with the
+                // instantiation mapper.
+                var templateMapper = combineTypeMappers(type.mapper, createTypeMapper([typeParameter], [t]));
+                var propType = instantiateType(templateType, templateMapper);
+                // If the current iteration type constituent is a string literal type, create a property.
+                // Otherwise, for type string create a string index signature.
+                if (t.flags & 2240 /* StringOrNumberLiteralOrUnique */) {
+                    var propName = getLateBoundNameFromType(t);
+                    var modifiersProp = getPropertyOfType(modifiersType, propName);
+                    var isOptional = !!(templateModifiers & 4 /* IncludeOptional */ ||
+                        !(templateModifiers & 8 /* ExcludeOptional */) && modifiersProp && modifiersProp.flags & 16777216 /* Optional */);
+                    var isReadonly = !!(templateModifiers & 1 /* IncludeReadonly */ ||
+                        !(templateModifiers & 2 /* ExcludeReadonly */) && modifiersProp && isReadonlySymbol(modifiersProp));
+                    var prop = createSymbol(4 /* Property */ | (isOptional ? 16777216 /* Optional */ : 0), propName, isReadonly ? 8 /* Readonly */ : 0);
+                    // When creating an optional property in strictNullChecks mode, if 'undefined' isn't assignable to the
+                    // type, we include 'undefined' in the type. Similarly, when creating a non-optional property in strictNullChecks
+                    // mode, if the underlying property is optional we remove 'undefined' from the type.
+                    prop.type = strictNullChecks && isOptional && !isTypeAssignableTo(undefinedType, propType) ? getOptionalType(propType) :
+                        strictNullChecks && !isOptional && modifiersProp && modifiersProp.flags & 16777216 /* Optional */ ? getTypeWithFacts(propType, 131072 /* NEUndefined */) :
+                            propType;
+                    if (origin) {
+                        prop.syntheticOrigin = origin;
+                        prop.declarations = origin.declarations;
+                    }
+                    prop.nameType = t;
+                    members.set(propName, prop);
+                }
+                else if (t.flags & (1 /* Any */ | 4 /* String */)) {
+                    stringIndexInfo = createIndexInfo(propType, !!(templateModifiers & 1 /* IncludeReadonly */));
+                }
+                else if (t.flags & 8 /* Number */) {
+                    numberIndexInfo = createIndexInfo(propType, !!(templateModifiers & 1 /* IncludeReadonly */));
+                }
+            }
+        }
+        function getTypeParameterFromMappedType(type) {
+            return type.typeParameter ||
+                (type.typeParameter = getDeclaredTypeOfTypeParameter(getSymbolOfNode(type.declaration.typeParameter)));
+        }
+        function getConstraintTypeFromMappedType(type) {
+            return type.constraintType ||
+                (type.constraintType = instantiateType(getConstraintOfTypeParameter(getTypeParameterFromMappedType(type)), type.mapper || identityMapper) || errorType);
+        }
+        function getTemplateTypeFromMappedType(type) {
+            return type.templateType ||
+                (type.templateType = type.declaration.type ?
+                    instantiateType(addOptionality(getTypeFromTypeNode(type.declaration.type), !!(getMappedTypeModifiers(type) & 4 /* IncludeOptional */)), type.mapper || identityMapper) :
+                    errorType);
+        }
+        function getConstraintDeclarationForMappedType(type) {
+            return type.declaration.typeParameter.constraint;
+        }
+        function isMappedTypeWithKeyofConstraintDeclaration(type) {
+            var constraintDeclaration = getConstraintDeclarationForMappedType(type); // TODO: GH#18217
+            return constraintDeclaration.kind === 175 /* TypeOperator */ &&
+                constraintDeclaration.operator === 128 /* KeyOfKeyword */;
+        }
+        function getModifiersTypeFromMappedType(type) {
+            if (!type.modifiersType) {
+                if (isMappedTypeWithKeyofConstraintDeclaration(type)) {
+                    // If the constraint declaration is a 'keyof T' node, the modifiers type is T. We check
+                    // AST nodes here because, when T is a non-generic type, the logic below eagerly resolves
+                    // 'keyof T' to a literal union type and we can't recover T from that type.
+                    type.modifiersType = instantiateType(getTypeFromTypeNode(getConstraintDeclarationForMappedType(type).type), type.mapper || identityMapper);
+                }
+                else {
+                    // Otherwise, get the declared constraint type, and if the constraint type is a type parameter,
+                    // get the constraint of that type parameter. If the resulting type is an indexed type 'keyof T',
+                    // the modifiers type is T. Otherwise, the modifiers type is {}.
+                    var declaredType = getTypeFromMappedTypeNode(type.declaration);
+                    var constraint = getConstraintTypeFromMappedType(declaredType);
+                    var extendedConstraint = constraint && constraint.flags & 65536 /* TypeParameter */ ? getConstraintOfTypeParameter(constraint) : constraint;
+                    type.modifiersType = extendedConstraint && extendedConstraint.flags & 1048576 /* Index */ ? instantiateType(extendedConstraint.type, type.mapper || identityMapper) : emptyObjectType;
+                }
+            }
+            return type.modifiersType;
+        }
+        function getMappedTypeModifiers(type) {
+            var declaration = type.declaration;
+            return (declaration.readonlyToken ? declaration.readonlyToken.kind === 38 /* MinusToken */ ? 2 /* ExcludeReadonly */ : 1 /* IncludeReadonly */ : 0) |
+                (declaration.questionToken ? declaration.questionToken.kind === 38 /* MinusToken */ ? 8 /* ExcludeOptional */ : 4 /* IncludeOptional */ : 0);
+        }
+        function getMappedTypeOptionality(type) {
+            var modifiers = getMappedTypeModifiers(type);
+            return modifiers & 8 /* ExcludeOptional */ ? -1 : modifiers & 4 /* IncludeOptional */ ? 1 : 0;
+        }
+        function getCombinedMappedTypeOptionality(type) {
+            var optionality = getMappedTypeOptionality(type);
+            var modifiersType = getModifiersTypeFromMappedType(type);
+            return optionality || (isGenericMappedType(modifiersType) ? getMappedTypeOptionality(modifiersType) : 0);
+        }
+        function isPartialMappedType(type) {
+            return !!(ts.getObjectFlags(type) & 32 /* Mapped */ && getMappedTypeModifiers(type) & 4 /* IncludeOptional */);
+        }
+        function isGenericMappedType(type) {
+            return !!(ts.getObjectFlags(type) & 32 /* Mapped */) && isGenericIndexType(getConstraintTypeFromMappedType(type));
+        }
+        function resolveStructuredTypeMembers(type) {
+            if (!type.members) {
+                if (type.flags & 131072 /* Object */) {
+                    if (type.objectFlags & 4 /* Reference */) {
+                        resolveTypeReferenceMembers(type);
+                    }
+                    else if (type.objectFlags & 3 /* ClassOrInterface */) {
+                        resolveClassOrInterfaceMembers(type);
+                    }
+                    else if (type.objectFlags & 2048 /* ReverseMapped */) {
+                        resolveReverseMappedTypeMembers(type);
+                    }
+                    else if (type.objectFlags & 16 /* Anonymous */) {
+                        resolveAnonymousTypeMembers(type);
+                    }
+                    else if (type.objectFlags & 32 /* Mapped */) {
+                        resolveMappedTypeMembers(type);
+                    }
+                }
+                else if (type.flags & 262144 /* Union */) {
+                    resolveUnionTypeMembers(type);
+                }
+                else if (type.flags & 524288 /* Intersection */) {
+                    resolveIntersectionTypeMembers(type);
+                }
+            }
+            return type;
+        }
+        /** Return properties of an object type or an empty array for other types */
+        function getPropertiesOfObjectType(type) {
+            if (type.flags & 131072 /* Object */) {
+                return resolveStructuredTypeMembers(type).properties;
+            }
+            return ts.emptyArray;
+        }
+        /** If the given type is an object type and that type has a property by the given name,
+         * return the symbol for that property. Otherwise return undefined.
+         */
+        function getPropertyOfObjectType(type, name) {
+            if (type.flags & 131072 /* Object */) {
+                var resolved = resolveStructuredTypeMembers(type);
+                var symbol = resolved.members.get(name);
+                if (symbol && symbolIsValue(symbol)) {
+                    return symbol;
+                }
+            }
+        }
+        function getPropertiesOfUnionOrIntersectionType(type) {
+            if (!type.resolvedProperties) {
+                var members = ts.createSymbolTable();
+                for (var _i = 0, _a = type.types; _i < _a.length; _i++) {
+                    var current = _a[_i];
+                    for (var _b = 0, _c = getPropertiesOfType(current); _b < _c.length; _b++) {
+                        var prop = _c[_b];
+                        if (!members.has(prop.escapedName)) {
+                            var combinedProp = getPropertyOfUnionOrIntersectionType(type, prop.escapedName);
+                            if (combinedProp) {
+                                members.set(prop.escapedName, combinedProp);
+                            }
+                        }
+                    }
+                    // The properties of a union type are those that are present in all constituent types, so
+                    // we only need to check the properties of the first type
+                    if (type.flags & 262144 /* Union */) {
+                        break;
+                    }
+                }
+                type.resolvedProperties = getNamedMembers(members);
+            }
+            return type.resolvedProperties;
+        }
+        function getPropertiesOfType(type) {
+            type = getApparentType(type);
+            return type.flags & 786432 /* UnionOrIntersection */ ?
+                getPropertiesOfUnionOrIntersectionType(type) :
+                getPropertiesOfObjectType(type);
+        }
+        function getAllPossiblePropertiesOfTypes(types) {
+            var unionType = getUnionType(types);
+            if (!(unionType.flags & 262144 /* Union */)) {
+                return getAugmentedPropertiesOfType(unionType);
+            }
+            var props = ts.createSymbolTable();
+            for (var _i = 0, types_3 = types; _i < types_3.length; _i++) {
+                var memberType = types_3[_i];
+                for (var _a = 0, _b = getAugmentedPropertiesOfType(memberType); _a < _b.length; _a++) {
+                    var escapedName = _b[_a].escapedName;
+                    if (!props.has(escapedName)) {
+                        var prop = createUnionOrIntersectionProperty(unionType, escapedName);
+                        // May be undefined if the property is private
+                        if (prop)
+                            props.set(escapedName, prop);
+                    }
+                }
+            }
+            return ts.arrayFrom(props.values());
+        }
+        function getConstraintOfType(type) {
+            return type.flags & 65536 /* TypeParameter */ ? getConstraintOfTypeParameter(type) :
+                type.flags & 2097152 /* IndexedAccess */ ? getConstraintOfIndexedAccess(type) :
+                    type.flags & 4194304 /* Conditional */ ? getConstraintOfConditionalType(type) :
+                        getBaseConstraintOfType(type);
+        }
+        function getConstraintOfTypeParameter(typeParameter) {
+            return hasNonCircularBaseConstraint(typeParameter) ? getConstraintFromTypeParameter(typeParameter) : undefined;
+        }
+        function getConstraintOfIndexedAccess(type) {
+            var objectType = getBaseConstraintOfType(type.objectType) || type.objectType;
+            var indexType = getBaseConstraintOfType(type.indexType) || type.indexType;
+            var constraint = !isGenericObjectType(objectType) && !isGenericIndexType(indexType) ? getIndexedAccessType(objectType, indexType) : undefined;
+            return constraint && constraint !== errorType ? constraint : undefined;
+        }
+        function getDefaultConstraintOfConditionalType(type) {
+            if (!type.resolvedDefaultConstraint) {
+                var rootTrueType = type.root.trueType;
+                var rootTrueConstraint = rootTrueType.flags & 8388608 /* Substitution */ ? rootTrueType.substitute : rootTrueType;
+                type.resolvedDefaultConstraint = getUnionType([instantiateType(rootTrueConstraint, type.combinedMapper || type.mapper), getFalseTypeFromConditionalType(type)]);
+            }
+            return type.resolvedDefaultConstraint;
+        }
+        function getConstraintOfDistributiveConditionalType(type) {
+            // Check if we have a conditional type of the form 'T extends U ? X : Y', where T is a constrained
+            // type parameter. If so, create an instantiation of the conditional type where T is replaced
+            // with its constraint. We do this because if the constraint is a union type it will be distributed
+            // over the conditional type and possibly reduced. For example, 'T extends undefined ? never : T'
+            // removes 'undefined' from T.
+            if (type.root.isDistributive) {
+                var constraint = getConstraintOfType(getSimplifiedType(type.checkType));
+                if (constraint) {
+                    var mapper = makeUnaryTypeMapper(type.root.checkType, constraint);
+                    var instantiated = getConditionalTypeInstantiation(type, combineTypeMappers(mapper, type.mapper));
+                    if (!(instantiated.flags & 32768 /* Never */)) {
+                        return instantiated;
+                    }
+                }
+            }
+            return undefined;
+        }
+        function getConstraintOfConditionalType(type) {
+            return getConstraintOfDistributiveConditionalType(type) || getDefaultConstraintOfConditionalType(type);
+        }
+        function getUnionConstraintOfIntersection(type, targetIsUnion) {
+            var constraints;
+            var hasDisjointDomainType = false;
+            for (var _i = 0, _a = type.types; _i < _a.length; _i++) {
+                var t = _a[_i];
+                if (t.flags & 15794176 /* Instantiable */) {
+                    // We keep following constraints as long as we have an instantiable type that is known
+                    // not to be circular or infinite (hence we stop on index access types).
+                    var constraint = getConstraintOfType(t);
+                    while (constraint && constraint.flags & (65536 /* TypeParameter */ | 1048576 /* Index */ | 4194304 /* Conditional */)) {
+                        constraint = getConstraintOfType(constraint);
+                    }
+                    if (constraint) {
+                        // A constraint that isn't a union type implies that the final type would be a non-union
+                        // type as well. Since non-union constraints are of no interest, we can exit here.
+                        if (!(constraint.flags & 262144 /* Union */)) {
+                            return undefined;
+                        }
+                        constraints = ts.append(constraints, constraint);
+                    }
+                }
+                else if (t.flags & 16809468 /* DisjointDomains */) {
+                    hasDisjointDomainType = true;
+                }
+            }
+            // If the target is a union type or if we are intersecting with types belonging to one of the
+            // disjoint domans, we may end up producing a constraint that hasn't been examined before.
+            if (constraints && (targetIsUnion || hasDisjointDomainType)) {
+                if (hasDisjointDomainType) {
+                    // We add any types belong to one of the disjoint domans because they might cause the final
+                    // intersection operation to reduce the union constraints.
+                    for (var _b = 0, _c = type.types; _b < _c.length; _b++) {
+                        var t = _c[_b];
+                        if (t.flags & 16809468 /* DisjointDomains */) {
+                            constraints = ts.append(constraints, t);
+                        }
+                    }
+                }
+                return getIntersectionType(constraints);
+            }
+            return undefined;
+        }
+        function getBaseConstraintOfInstantiableNonPrimitiveUnionOrIntersection(type) {
+            if (type.flags & (14745600 /* InstantiableNonPrimitive */ | 786432 /* UnionOrIntersection */)) {
+                var constraint = getResolvedBaseConstraint(type);
+                if (constraint !== noConstraintType && constraint !== circularConstraintType) {
+                    return constraint;
+                }
+            }
+        }
+        function getBaseConstraintOfType(type) {
+            var constraint = getBaseConstraintOfInstantiableNonPrimitiveUnionOrIntersection(type);
+            if (!constraint && type.flags & 1048576 /* Index */) {
+                return keyofConstraintType;
+            }
+            return constraint;
+        }
+        /**
+         * This is similar to `getBaseConstraintOfType` except it returns the input type if there's no base constraint, instead of `undefined`
+         * It also doesn't map indexes to `string`, as where this is used this would be unneeded (and likely undesirable)
+         */
+        function getBaseConstraintOrType(type) {
+            return getBaseConstraintOfType(type) || type;
+        }
+        function hasNonCircularBaseConstraint(type) {
+            return getResolvedBaseConstraint(type) !== circularConstraintType;
+        }
+        /**
+         * Return the resolved base constraint of a type variable. The noConstraintType singleton is returned if the
+         * type variable has no constraint, and the circularConstraintType singleton is returned if the constraint
+         * circularly references the type variable.
+         */
+        function getResolvedBaseConstraint(type) {
+            var circular;
+            if (!type.resolvedBaseConstraint) {
+                var constraint = getBaseConstraint(type);
+                type.resolvedBaseConstraint = circular ? circularConstraintType : getTypeWithThisArgument(constraint || noConstraintType, type);
+            }
+            return type.resolvedBaseConstraint;
+            function getBaseConstraint(t) {
+                if (!pushTypeResolution(t, 4 /* ResolvedBaseConstraint */)) {
+                    circular = true;
+                    return undefined;
+                }
+                var result = computeBaseConstraint(getSimplifiedType(t));
+                if (!popTypeResolution()) {
+                    circular = true;
+                    return undefined;
+                }
+                return result;
+            }
+            function computeBaseConstraint(t) {
+                if (t.flags & 65536 /* TypeParameter */) {
+                    var constraint = getConstraintFromTypeParameter(t);
+                    return t.isThisType || !constraint ?
+                        constraint :
+                        getBaseConstraint(constraint);
+                }
+                if (t.flags & 786432 /* UnionOrIntersection */) {
+                    var types = t.types;
+                    var baseTypes = [];
+                    for (var _i = 0, types_4 = types; _i < types_4.length; _i++) {
+                        var type_3 = types_4[_i];
+                        var baseType = getBaseConstraint(type_3);
+                        if (baseType) {
+                            baseTypes.push(baseType);
+                        }
+                    }
+                    return t.flags & 262144 /* Union */ && baseTypes.length === types.length ? getUnionType(baseTypes) :
+                        t.flags & 524288 /* Intersection */ && baseTypes.length ? getIntersectionType(baseTypes) :
+                            undefined;
+                }
+                if (t.flags & 1048576 /* Index */) {
+                    return keyofConstraintType;
+                }
+                if (t.flags & 2097152 /* IndexedAccess */) {
+                    var baseObjectType = getBaseConstraint(t.objectType);
+                    var baseIndexType = getBaseConstraint(t.indexType);
+                    var baseIndexedAccess = baseObjectType && baseIndexType ? getIndexedAccessType(baseObjectType, baseIndexType) : undefined;
+                    return baseIndexedAccess && baseIndexedAccess !== errorType ? getBaseConstraint(baseIndexedAccess) : undefined;
+                }
+                if (t.flags & 4194304 /* Conditional */) {
+                    var constraint = getConstraintOfConditionalType(t);
+                    return constraint && getBaseConstraint(constraint);
+                }
+                if (t.flags & 8388608 /* Substitution */) {
+                    return getBaseConstraint(t.substitute);
+                }
+                if (isGenericMappedType(t)) {
+                    return emptyObjectType;
+                }
+                return t;
+            }
+        }
+        function getApparentTypeOfIntersectionType(type) {
+            return type.resolvedApparentType || (type.resolvedApparentType = getTypeWithThisArgument(type, type, /*apparentType*/ true));
+        }
+        function getResolvedTypeParameterDefault(typeParameter) {
+            if (!typeParameter.default) {
+                if (typeParameter.target) {
+                    var targetDefault = getResolvedTypeParameterDefault(typeParameter.target);
+                    typeParameter.default = targetDefault ? instantiateType(targetDefault, typeParameter.mapper) : noConstraintType;
+                }
+                else {
+                    // To block recursion, set the initial value to the resolvingDefaultType.
+                    typeParameter.default = resolvingDefaultType;
+                    var defaultDeclaration = typeParameter.symbol && ts.forEach(typeParameter.symbol.declarations, function (decl) { return ts.isTypeParameterDeclaration(decl) && decl.default; });
+                    var defaultType = defaultDeclaration ? getTypeFromTypeNode(defaultDeclaration) : noConstraintType;
+                    if (typeParameter.default === resolvingDefaultType) {
+                        // If we have not been called recursively, set the correct default type.
+                        typeParameter.default = defaultType;
+                    }
+                }
+            }
+            else if (typeParameter.default === resolvingDefaultType) {
+                // If we are called recursively for this type parameter, mark the default as circular.
+                typeParameter.default = circularConstraintType;
+            }
+            return typeParameter.default;
+        }
+        /**
+         * Gets the default type for a type parameter.
+         *
+         * If the type parameter is the result of an instantiation, this gets the instantiated
+         * default type of its target. If the type parameter has no default type or the default is
+         * circular, `undefined` is returned.
+         */
+        function getDefaultFromTypeParameter(typeParameter) {
+            var defaultType = getResolvedTypeParameterDefault(typeParameter);
+            return defaultType !== noConstraintType && defaultType !== circularConstraintType ? defaultType : undefined;
+        }
+        function hasNonCircularTypeParameterDefault(typeParameter) {
+            return getResolvedTypeParameterDefault(typeParameter) !== circularConstraintType;
+        }
+        /**
+         * Indicates whether the declaration of a typeParameter has a default type.
+         */
+        function hasTypeParameterDefault(typeParameter) {
+            return !!(typeParameter.symbol && ts.forEach(typeParameter.symbol.declarations, function (decl) { return ts.isTypeParameterDeclaration(decl) && decl.default; }));
+        }
+        /**
+         * For a type parameter, return the base constraint of the type parameter. For the string, number,
+         * boolean, and symbol primitive types, return the corresponding object types. Otherwise return the
+         * type itself. Note that the apparent type of a union type is the union type itself.
+         */
+        function getApparentType(type) {
+            var t = type.flags & 15794176 /* Instantiable */ ? getBaseConstraintOfType(type) || emptyObjectType : type;
+            return t.flags & 524288 /* Intersection */ ? getApparentTypeOfIntersectionType(t) :
+                t.flags & 68 /* StringLike */ ? globalStringType :
+                    t.flags & 168 /* NumberLike */ ? globalNumberType :
+                        t.flags & 272 /* BooleanLike */ ? globalBooleanType :
+                            t.flags & 3072 /* ESSymbolLike */ ? getGlobalESSymbolType(/*reportErrors*/ languageVersion >= 2 /* ES2015 */) :
+                                t.flags & 16777216 /* NonPrimitive */ ? emptyObjectType :
+                                    t.flags & 1048576 /* Index */ ? keyofConstraintType :
+                                        t;
+        }
+        function createUnionOrIntersectionProperty(containingType, name) {
+            var props;
+            var isUnion = containingType.flags & 262144 /* Union */;
+            var excludeModifiers = isUnion ? 24 /* NonPublicAccessibilityModifier */ : 0;
+            // Flags we want to propagate to the result if they exist in all source symbols
+            var commonFlags = isUnion ? 0 /* None */ : 16777216 /* Optional */;
+            var syntheticFlag = 4 /* SyntheticMethod */;
+            var checkFlags = 0;
+            for (var _i = 0, _a = containingType.types; _i < _a.length; _i++) {
+                var current = _a[_i];
+                var type = getApparentType(current);
+                if (type !== errorType) {
+                    var prop = getPropertyOfType(type, name);
+                    var modifiers = prop ? ts.getDeclarationModifierFlagsFromSymbol(prop) : 0;
+                    if (prop && !(modifiers & excludeModifiers)) {
+                        commonFlags &= prop.flags;
+                        props = ts.appendIfUnique(props, prop);
+                        checkFlags |= (isReadonlySymbol(prop) ? 8 /* Readonly */ : 0) |
+                            (!(modifiers & 24 /* NonPublicAccessibilityModifier */) ? 64 /* ContainsPublic */ : 0) |
+                            (modifiers & 16 /* Protected */ ? 128 /* ContainsProtected */ : 0) |
+                            (modifiers & 8 /* Private */ ? 256 /* ContainsPrivate */ : 0) |
+                            (modifiers & 32 /* Static */ ? 512 /* ContainsStatic */ : 0);
+                        if (!isPrototypeProperty(prop)) {
+                            syntheticFlag = 2 /* SyntheticProperty */;
+                        }
+                    }
+                    else if (isUnion) {
+                        checkFlags |= 16 /* Partial */;
+                    }
+                }
+            }
+            if (!props) {
+                return undefined;
+            }
+            if (props.length === 1 && !(checkFlags & 16 /* Partial */)) {
+                return props[0];
+            }
+            var declarations;
+            var commonType;
+            var nameType;
+            var propTypes = [];
+            var first = true;
+            var commonValueDeclaration;
+            var hasNonUniformValueDeclaration = false;
+            for (var _b = 0, props_1 = props; _b < props_1.length; _b++) {
+                var prop = props_1[_b];
+                if (!commonValueDeclaration) {
+                    commonValueDeclaration = prop.valueDeclaration;
+                }
+                else if (prop.valueDeclaration !== commonValueDeclaration) {
+                    hasNonUniformValueDeclaration = true;
+                }
+                declarations = ts.addRange(declarations, prop.declarations);
+                var type = getTypeOfSymbol(prop);
+                if (first) {
+                    commonType = type;
+                    nameType = prop.nameType;
+                    first = false;
+                }
+                else {
+                    if (type !== commonType) {
+                        checkFlags |= 32 /* HasNonUniformType */;
+                    }
+                }
+                propTypes.push(type);
+            }
+            var result = createSymbol(4 /* Property */ | commonFlags, name, syntheticFlag | checkFlags);
+            result.containingType = containingType;
+            if (!hasNonUniformValueDeclaration && commonValueDeclaration) {
+                result.valueDeclaration = commonValueDeclaration;
+            }
+            result.declarations = declarations;
+            result.nameType = nameType;
+            result.type = isUnion ? getUnionType(propTypes) : getIntersectionType(propTypes);
+            return result;
+        }
+        // Return the symbol for a given property in a union or intersection type, or undefined if the property
+        // does not exist in any constituent type. Note that the returned property may only be present in some
+        // constituents, in which case the isPartial flag is set when the containing type is union type. We need
+        // these partial properties when identifying discriminant properties, but otherwise they are filtered out
+        // and do not appear to be present in the union type.
+        function getUnionOrIntersectionProperty(type, name) {
+            var properties = type.propertyCache || (type.propertyCache = ts.createSymbolTable());
+            var property = properties.get(name);
+            if (!property) {
+                property = createUnionOrIntersectionProperty(type, name);
+                if (property) {
+                    properties.set(name, property);
+                }
+            }
+            return property;
+        }
+        function getPropertyOfUnionOrIntersectionType(type, name) {
+            var property = getUnionOrIntersectionProperty(type, name);
+            // We need to filter out partial properties in union types
+            return property && !(ts.getCheckFlags(property) & 16 /* Partial */) ? property : undefined;
+        }
+        /**
+         * Return the symbol for the property with the given name in the given type. Creates synthetic union properties when
+         * necessary, maps primitive types and type parameters are to their apparent types, and augments with properties from
+         * Object and Function as appropriate.
+         *
+         * @param type a type to look up property from
+         * @param name a name of property to look up in a given type
+         */
+        function getPropertyOfType(type, name) {
+            type = getApparentType(type);
+            if (type.flags & 131072 /* Object */) {
+                var resolved = resolveStructuredTypeMembers(type);
+                var symbol = resolved.members.get(name);
+                if (symbol && symbolIsValue(symbol)) {
+                    return symbol;
+                }
+                if (resolved === anyFunctionType || resolved.callSignatures.length || resolved.constructSignatures.length) {
+                    var symbol_1 = getPropertyOfObjectType(globalFunctionType, name);
+                    if (symbol_1) {
+                        return symbol_1;
+                    }
+                }
+                return getPropertyOfObjectType(globalObjectType, name);
+            }
+            if (type.flags & 786432 /* UnionOrIntersection */) {
+                return getPropertyOfUnionOrIntersectionType(type, name);
+            }
+            return undefined;
+        }
+        function getSignaturesOfStructuredType(type, kind) {
+            if (type.flags & 917504 /* StructuredType */) {
+                var resolved = resolveStructuredTypeMembers(type);
+                return kind === 0 /* Call */ ? resolved.callSignatures : resolved.constructSignatures;
+            }
+            return ts.emptyArray;
+        }
+        /**
+         * Return the signatures of the given kind in the given type. Creates synthetic union signatures when necessary and
+         * maps primitive types and type parameters are to their apparent types.
+         */
+        function getSignaturesOfType(type, kind) {
+            return getSignaturesOfStructuredType(getApparentType(type), kind);
+        }
+        function getIndexInfoOfStructuredType(type, kind) {
+            if (type.flags & 917504 /* StructuredType */) {
+                var resolved = resolveStructuredTypeMembers(type);
+                return kind === 0 /* String */ ? resolved.stringIndexInfo : resolved.numberIndexInfo;
+            }
+        }
+        function getIndexTypeOfStructuredType(type, kind) {
+            var info = getIndexInfoOfStructuredType(type, kind);
+            return info && info.type;
+        }
+        // Return the indexing info of the given kind in the given type. Creates synthetic union index types when necessary and
+        // maps primitive types and type parameters are to their apparent types.
+        function getIndexInfoOfType(type, kind) {
+            return getIndexInfoOfStructuredType(getApparentType(type), kind);
+        }
+        // Return the index type of the given kind in the given type. Creates synthetic union index types when necessary and
+        // maps primitive types and type parameters are to their apparent types.
+        function getIndexTypeOfType(type, kind) {
+            return getIndexTypeOfStructuredType(getApparentType(type), kind);
+        }
+        function getImplicitIndexTypeOfType(type, kind) {
+            if (isObjectTypeWithInferableIndex(type)) {
+                var propTypes = [];
+                for (var _i = 0, _a = getPropertiesOfType(type); _i < _a.length; _i++) {
+                    var prop = _a[_i];
+                    if (kind === 0 /* String */ || isNumericLiteralName(prop.escapedName)) {
+                        propTypes.push(getTypeOfSymbol(prop));
+                    }
+                }
+                if (propTypes.length) {
+                    return getUnionType(propTypes, 2 /* Subtype */);
+                }
+            }
+            return undefined;
+        }
+        // Return list of type parameters with duplicates removed (duplicate identifier errors are generated in the actual
+        // type checking functions).
+        function getTypeParametersFromDeclaration(declaration) {
+            var result;
+            for (var _i = 0, _a = ts.getEffectiveTypeParameterDeclarations(declaration); _i < _a.length; _i++) {
+                var node = _a[_i];
+                result = ts.appendIfUnique(result, getDeclaredTypeOfTypeParameter(node.symbol));
+            }
+            return result;
+        }
+        function symbolsToArray(symbols) {
+            var result = [];
+            symbols.forEach(function (symbol, id) {
+                if (!isReservedMemberName(id)) {
+                    result.push(symbol);
+                }
+            });
+            return result;
+        }
+        function isJSDocOptionalParameter(node) {
+            return ts.isInJavaScriptFile(node) && (
+            // node.type should only be a JSDocOptionalType when node is a parameter of a JSDocFunctionType
+            node.type && node.type.kind === 283 /* JSDocOptionalType */
+                || ts.getJSDocParameterTags(node).some(function (_a) {
+                    var isBracketed = _a.isBracketed, typeExpression = _a.typeExpression;
+                    return isBracketed || !!typeExpression && typeExpression.type.kind === 283 /* JSDocOptionalType */;
+                }));
+        }
+        function tryFindAmbientModule(moduleName, withAugmentations) {
+            if (ts.isExternalModuleNameRelative(moduleName)) {
+                return undefined;
+            }
+            var symbol = getSymbol(globals, '"' + moduleName + '"', 512 /* ValueModule */);
+            // merged symbol is module declaration symbol combined with all augmentations
+            return symbol && withAugmentations ? getMergedSymbol(symbol) : symbol;
+        }
+        function isOptionalParameter(node) {
+            if (ts.hasQuestionToken(node) || isOptionalJSDocParameterTag(node) || isJSDocOptionalParameter(node)) {
+                return true;
+            }
+            if (node.initializer) {
+                var signature = getSignatureFromDeclaration(node.parent);
+                var parameterIndex = node.parent.parameters.indexOf(node);
+                ts.Debug.assert(parameterIndex >= 0);
+                return parameterIndex >= signature.minArgumentCount;
+            }
+            var iife = ts.getImmediatelyInvokedFunctionExpression(node.parent);
+            if (iife) {
+                return !node.type &&
+                    !node.dotDotDotToken &&
+                    node.parent.parameters.indexOf(node) >= iife.arguments.length;
+            }
+            return false;
+        }
+        function isOptionalJSDocParameterTag(node) {
+            if (!ts.isJSDocParameterTag(node)) {
+                return false;
+            }
+            var isBracketed = node.isBracketed, typeExpression = node.typeExpression;
+            return isBracketed || !!typeExpression && typeExpression.type.kind === 283 /* JSDocOptionalType */;
+        }
+        function createTypePredicateFromTypePredicateNode(node) {
+            var parameterName = node.parameterName;
+            var type = getTypeFromTypeNode(node.type);
+            if (parameterName.kind === 71 /* Identifier */) {
+                return createIdentifierTypePredicate(parameterName && parameterName.escapedText, // TODO: GH#18217
+                parameterName && getTypePredicateParameterIndex(node.parent.parameters, parameterName), type);
+            }
+            else {
+                return createThisTypePredicate(type);
+            }
+        }
+        function createIdentifierTypePredicate(parameterName, parameterIndex, type) {
+            return { kind: 1 /* Identifier */, parameterName: parameterName, parameterIndex: parameterIndex, type: type };
+        }
+        function createThisTypePredicate(type) {
+            return { kind: 0 /* This */, type: type };
+        }
+        /**
+         * Gets the minimum number of type arguments needed to satisfy all non-optional type
+         * parameters.
+         */
+        function getMinTypeArgumentCount(typeParameters) {
+            var minTypeArgumentCount = 0;
+            if (typeParameters) {
+                for (var i = 0; i < typeParameters.length; i++) {
+                    if (!hasTypeParameterDefault(typeParameters[i])) {
+                        minTypeArgumentCount = i + 1;
+                    }
+                }
+            }
+            return minTypeArgumentCount;
+        }
+        function fillMissingTypeArguments(typeArguments, typeParameters, minTypeArgumentCount, isJavaScriptImplicitAny) {
+            var numTypeParameters = ts.length(typeParameters);
+            if (numTypeParameters) {
+                var numTypeArguments = ts.length(typeArguments);
+                if (isJavaScriptImplicitAny || (numTypeArguments >= minTypeArgumentCount && numTypeArguments <= numTypeParameters)) {
+                    if (!typeArguments) {
+                        typeArguments = [];
+                    }
+                    // Map an unsatisfied type parameter with a default type.
+                    // If a type parameter does not have a default type, or if the default type
+                    // is a forward reference, the empty object type is used.
+                    for (var i = numTypeArguments; i < numTypeParameters; i++) {
+                        typeArguments[i] = getDefaultTypeArgumentType(isJavaScriptImplicitAny);
+                    }
+                    for (var i = numTypeArguments; i < numTypeParameters; i++) {
+                        var mapper = createTypeMapper(typeParameters, typeArguments);
+                        var defaultType = getDefaultFromTypeParameter(typeParameters[i]);
+                        if (isJavaScriptImplicitAny && defaultType && isTypeIdenticalTo(defaultType, emptyObjectType)) {
+                            defaultType = anyType;
+                        }
+                        typeArguments[i] = defaultType ? instantiateType(defaultType, mapper) : getDefaultTypeArgumentType(isJavaScriptImplicitAny);
+                    }
+                    typeArguments.length = typeParameters.length;
+                }
+            }
+            return typeArguments;
+        }
+        function getSignatureFromDeclaration(declaration) {
+            var links = getNodeLinks(declaration);
+            if (!links.resolvedSignature) {
+                var parameters = [];
+                var hasLiteralTypes = false;
+                var minArgumentCount = 0;
+                var thisParameter = void 0;
+                var hasThisParameter = false;
+                var iife = ts.getImmediatelyInvokedFunctionExpression(declaration);
+                var isJSConstructSignature = ts.isJSDocConstructSignature(declaration);
+                var isUntypedSignatureInJSFile = !iife &&
+                    ts.isInJavaScriptFile(declaration) &&
+                    ts.isValueSignatureDeclaration(declaration) &&
+                    !ts.hasJSDocParameterTags(declaration) &&
+                    !ts.getJSDocType(declaration);
+                // If this is a JSDoc construct signature, then skip the first parameter in the
+                // parameter list.  The first parameter represents the return type of the construct
+                // signature.
+                for (var i = isJSConstructSignature ? 1 : 0; i < declaration.parameters.length; i++) {
+                    var param = declaration.parameters[i];
+                    var paramSymbol = param.symbol;
+                    var type = ts.isJSDocParameterTag(param) ? (param.typeExpression && param.typeExpression.type) : param.type;
+                    // Include parameter symbol instead of property symbol in the signature
+                    if (paramSymbol && !!(paramSymbol.flags & 4 /* Property */) && !ts.isBindingPattern(param.name)) {
+                        var resolvedSymbol = resolveName(param, paramSymbol.escapedName, 67216319 /* Value */, undefined, undefined, /*isUse*/ false);
+                        paramSymbol = resolvedSymbol;
+                    }
+                    if (i === 0 && paramSymbol.escapedName === "this") {
+                        hasThisParameter = true;
+                        thisParameter = param.symbol;
+                    }
+                    else {
+                        parameters.push(paramSymbol);
+                    }
+                    if (type && type.kind === 178 /* LiteralType */) {
+                        hasLiteralTypes = true;
+                    }
+                    // Record a new minimum argument count if this is not an optional parameter
+                    var isOptionalParameter_1 = isOptionalJSDocParameterTag(param) ||
+                        param.initializer || param.questionToken || param.dotDotDotToken ||
+                        iife && parameters.length > iife.arguments.length && !type ||
+                        isUntypedSignatureInJSFile ||
+                        isJSDocOptionalParameter(param);
+                    if (!isOptionalParameter_1) {
+                        minArgumentCount = parameters.length;
+                    }
+                }
+                // If only one accessor includes a this-type annotation, the other behaves as if it had the same type annotation
+                if ((declaration.kind === 156 /* GetAccessor */ || declaration.kind === 157 /* SetAccessor */) &&
+                    !hasNonBindableDynamicName(declaration) &&
+                    (!hasThisParameter || !thisParameter)) {
+                    var otherKind = declaration.kind === 156 /* GetAccessor */ ? 157 /* SetAccessor */ : 156 /* GetAccessor */;
+                    var other = ts.getDeclarationOfKind(getSymbolOfNode(declaration), otherKind);
+                    if (other) {
+                        thisParameter = getAnnotatedAccessorThisParameter(other);
+                    }
+                }
+                var classType = declaration.kind === 155 /* Constructor */ ?
+                    getDeclaredTypeOfClassOrInterface(getMergedSymbol(declaration.parent.symbol))
+                    : undefined;
+                var typeParameters = classType ? classType.localTypeParameters : getTypeParametersFromDeclaration(declaration);
+                var returnType = getSignatureReturnTypeFromDeclaration(declaration, isJSConstructSignature, classType);
+                var hasRestLikeParameter = ts.hasRestParameter(declaration) || ts.isInJavaScriptFile(declaration) && maybeAddJsSyntheticRestParameter(declaration, parameters);
+                links.resolvedSignature = createSignature(declaration, typeParameters, thisParameter, parameters, returnType, /*resolvedTypePredicate*/ undefined, minArgumentCount, hasRestLikeParameter, hasLiteralTypes);
+            }
+            return links.resolvedSignature;
+        }
+        /**
+         * A JS function gets a synthetic rest parameter if it references `arguments` AND:
+         * 1. It has no parameters but at least one `@param` with a type that starts with `...`
+         * OR
+         * 2. It has at least one parameter, and the last parameter has a matching `@param` with a type that starts with `...`
+         */
+        function maybeAddJsSyntheticRestParameter(declaration, parameters) {
+            if (ts.isJSDocSignature(declaration) || !containsArgumentsReference(declaration)) {
+                return false;
+            }
+            var lastParam = ts.lastOrUndefined(declaration.parameters);
+            var lastParamTags = lastParam ? ts.getJSDocParameterTags(lastParam) : ts.getJSDocTags(declaration).filter(ts.isJSDocParameterTag);
+            var lastParamVariadicType = ts.firstDefined(lastParamTags, function (p) {
+                return p.typeExpression && ts.isJSDocVariadicType(p.typeExpression.type) ? p.typeExpression.type : undefined;
+            });
+            var syntheticArgsSymbol = createSymbol(3 /* Variable */, "args");
+            syntheticArgsSymbol.type = lastParamVariadicType ? createArrayType(getTypeFromTypeNode(lastParamVariadicType.type)) : anyArrayType;
+            syntheticArgsSymbol.isRestParameter = true;
+            if (lastParamVariadicType) {
+                // Replace the last parameter with a rest parameter.
+                parameters.pop();
+            }
+            parameters.push(syntheticArgsSymbol);
+            return true;
+        }
+        function getSignatureReturnTypeFromDeclaration(declaration, isJSConstructSignature, classType) {
+            if (isJSConstructSignature) {
+                return getTypeFromTypeNode(declaration.parameters[0].type); // TODO: GH#18217
+            }
+            else if (classType) {
+                return classType;
+            }
+            var typeNode = ts.getEffectiveReturnTypeNode(declaration);
+            if (typeNode) {
+                return getTypeFromTypeNode(typeNode);
+            }
+            // TypeScript 1.0 spec (April 2014):
+            // If only one accessor includes a type annotation, the other behaves as if it had the same type annotation.
+            if (declaration.kind === 156 /* GetAccessor */ && !hasNonBindableDynamicName(declaration)) {
+                var setter = ts.getDeclarationOfKind(getSymbolOfNode(declaration), 157 /* SetAccessor */);
+                return getAnnotatedAccessorType(setter);
+            }
+            if (ts.nodeIsMissing(declaration.body)) {
+                return anyType;
+            }
+        }
+        function containsArgumentsReference(declaration) {
+            var links = getNodeLinks(declaration);
+            if (links.containsArgumentsReference === undefined) {
+                if (links.flags & 8192 /* CaptureArguments */) {
+                    links.containsArgumentsReference = true;
+                }
+                else {
+                    links.containsArgumentsReference = traverse(declaration.body);
+                }
+            }
+            return links.containsArgumentsReference;
+            function traverse(node) {
+                if (!node)
+                    return false;
+                switch (node.kind) {
+                    case 71 /* Identifier */:
+                        return node.escapedText === "arguments" && ts.isExpressionNode(node);
+                    case 152 /* PropertyDeclaration */:
+                    case 154 /* MethodDeclaration */:
+                    case 156 /* GetAccessor */:
+                    case 157 /* SetAccessor */:
+                        return node.name.kind === 147 /* ComputedPropertyName */
+                            && traverse(node.name);
+                    default:
+                        return !ts.nodeStartsNewLexicalEnvironment(node) && !ts.isPartOfTypeNode(node) && !!ts.forEachChild(node, traverse);
+                }
+            }
+        }
+        function getSignaturesOfSymbol(symbol) {
+            if (!symbol)
+                return ts.emptyArray;
+            var result = [];
+            for (var i = 0; i < symbol.declarations.length; i++) {
+                var decl = symbol.declarations[i];
+                if (!ts.isFunctionLike(decl))
+                    continue;
+                // Don't include signature if node is the implementation of an overloaded function. A node is considered
+                // an implementation node if it has a body and the previous node is of the same kind and immediately
+                // precedes the implementation node (i.e. has the same parent and ends where the implementation starts).
+                if (i > 0 && decl.body) {
+                    var previous = symbol.declarations[i - 1];
+                    if (decl.parent === previous.parent && decl.kind === previous.kind && decl.pos === previous.end) {
+                        continue;
+                    }
+                }
+                result.push(getSignatureFromDeclaration(decl));
+            }
+            return result;
+        }
+        function resolveExternalModuleTypeByLiteral(name) {
+            var moduleSym = resolveExternalModuleName(name, name);
+            if (moduleSym) {
+                var resolvedModuleSymbol = resolveExternalModuleSymbol(moduleSym);
+                if (resolvedModuleSymbol) {
+                    return getTypeOfSymbol(resolvedModuleSymbol);
+                }
+            }
+            return anyType;
+        }
+        function getThisTypeOfSignature(signature) {
+            if (signature.thisParameter) {
+                return getTypeOfSymbol(signature.thisParameter);
+            }
+        }
+        function signatureHasTypePredicate(signature) {
+            return getTypePredicateOfSignature(signature) !== undefined;
+        }
+        function getTypePredicateOfSignature(signature) {
+            if (!signature.resolvedTypePredicate) {
+                if (signature.target) {
+                    var targetTypePredicate = getTypePredicateOfSignature(signature.target);
+                    signature.resolvedTypePredicate = targetTypePredicate ? instantiateTypePredicate(targetTypePredicate, signature.mapper) : noTypePredicate;
+                }
+                else if (signature.unionSignatures) {
+                    signature.resolvedTypePredicate = getUnionTypePredicate(signature.unionSignatures) || noTypePredicate;
+                }
+                else {
+                    var declaration = signature.declaration;
+                    signature.resolvedTypePredicate = declaration && declaration.type && declaration.type.kind === 161 /* TypePredicate */ ?
+                        createTypePredicateFromTypePredicateNode(declaration.type) :
+                        noTypePredicate;
+                }
+                ts.Debug.assert(!!signature.resolvedTypePredicate);
+            }
+            return signature.resolvedTypePredicate === noTypePredicate ? undefined : signature.resolvedTypePredicate;
+        }
+        function getReturnTypeOfSignature(signature) {
+            if (!signature.resolvedReturnType) {
+                if (!pushTypeResolution(signature, 3 /* ResolvedReturnType */)) {
+                    return errorType;
+                }
+                var type = void 0;
+                if (signature.target) {
+                    type = instantiateType(getReturnTypeOfSignature(signature.target), signature.mapper);
+                }
+                else if (signature.unionSignatures) {
+                    type = getUnionType(ts.map(signature.unionSignatures, getReturnTypeOfSignature), 2 /* Subtype */);
+                }
+                else {
+                    type = getReturnTypeFromBody(signature.declaration);
+                }
+                if (!popTypeResolution()) {
+                    type = anyType;
+                    if (noImplicitAny) {
+                        var declaration = signature.declaration;
+                        var name = ts.getNameOfDeclaration(declaration);
+                        if (name) {
+                            error(name, ts.Diagnostics._0_implicitly_has_return_type_any_because_it_does_not_have_a_return_type_annotation_and_is_referenced_directly_or_indirectly_in_one_of_its_return_expressions, ts.declarationNameToString(name));
+                        }
+                        else {
+                            error(declaration, ts.Diagnostics.Function_implicitly_has_return_type_any_because_it_does_not_have_a_return_type_annotation_and_is_referenced_directly_or_indirectly_in_one_of_its_return_expressions);
+                        }
+                    }
+                }
+                signature.resolvedReturnType = type;
+            }
+            return signature.resolvedReturnType;
+        }
+        function isResolvingReturnTypeOfSignature(signature) {
+            return !signature.resolvedReturnType && findResolutionCycleStartIndex(signature, 3 /* ResolvedReturnType */) >= 0;
+        }
+        function getRestTypeOfSignature(signature) {
+            if (signature.hasRestParameter) {
+                var type = getTypeOfSymbol(ts.last(signature.parameters));
+                if (ts.getObjectFlags(type) & 4 /* Reference */ && type.target === globalArrayType) {
+                    return type.typeArguments[0];
+                }
+            }
+            return anyType;
+        }
+        function getSignatureInstantiation(signature, typeArguments, isJavascript) {
+            typeArguments = fillMissingTypeArguments(typeArguments, signature.typeParameters, getMinTypeArgumentCount(signature.typeParameters), isJavascript);
+            var instantiations = signature.instantiations || (signature.instantiations = ts.createMap());
+            var id = getTypeListId(typeArguments);
+            var instantiation = instantiations.get(id);
+            if (!instantiation) {
+                instantiations.set(id, instantiation = createSignatureInstantiation(signature, typeArguments));
+            }
+            return instantiation;
+        }
+        function createSignatureInstantiation(signature, typeArguments) {
+            return instantiateSignature(signature, createSignatureTypeMapper(signature, typeArguments), /*eraseTypeParameters*/ true);
+        }
+        function createSignatureTypeMapper(signature, typeArguments) {
+            return createTypeMapper(signature.typeParameters, typeArguments);
+        }
+        function getErasedSignature(signature) {
+            return signature.typeParameters ?
+                signature.erasedSignatureCache || (signature.erasedSignatureCache = createErasedSignature(signature)) :
+                signature;
+        }
+        function createErasedSignature(signature) {
+            // Create an instantiation of the signature where all type arguments are the any type.
+            return instantiateSignature(signature, createTypeEraser(signature.typeParameters), /*eraseTypeParameters*/ true);
+        }
+        function getCanonicalSignature(signature) {
+            return signature.typeParameters ?
+                signature.canonicalSignatureCache || (signature.canonicalSignatureCache = createCanonicalSignature(signature)) :
+                signature;
+        }
+        function createCanonicalSignature(signature) {
+            // Create an instantiation of the signature where each unconstrained type parameter is replaced with
+            // its original. When a generic class or interface is instantiated, each generic method in the class or
+            // interface is instantiated with a fresh set of cloned type parameters (which we need to handle scenarios
+            // where different generations of the same type parameter are in scope). This leads to a lot of new type
+            // identities, and potentially a lot of work comparing those identities, so here we create an instantiation
+            // that uses the original type identities for all unconstrained type parameters.
+            return getSignatureInstantiation(signature, ts.map(signature.typeParameters, function (tp) { return tp.target && !getConstraintOfTypeParameter(tp.target) ? tp.target : tp; }), ts.isInJavaScriptFile(signature.declaration));
+        }
+        function getBaseSignature(signature) {
+            var typeParameters = signature.typeParameters;
+            if (typeParameters) {
+                var typeEraser_1 = createTypeEraser(typeParameters);
+                var baseConstraints = ts.map(typeParameters, function (tp) { return instantiateType(getBaseConstraintOfType(tp), typeEraser_1) || emptyObjectType; });
+                return instantiateSignature(signature, createTypeMapper(typeParameters, baseConstraints), /*eraseTypeParameters*/ true);
+            }
+            return signature;
+        }
+        function getOrCreateTypeFromSignature(signature) {
+            // There are two ways to declare a construct signature, one is by declaring a class constructor
+            // using the constructor keyword, and the other is declaring a bare construct signature in an
+            // object type literal or interface (using the new keyword). Each way of declaring a constructor
+            // will result in a different declaration kind.
+            if (!signature.isolatedSignatureType) {
+                var isConstructor = signature.declaration.kind === 155 /* Constructor */ || signature.declaration.kind === 159 /* ConstructSignature */; // TODO: GH#18217
+                var type = createObjectType(16 /* Anonymous */);
+                type.members = emptySymbols;
+                type.properties = ts.emptyArray;
+                type.callSignatures = !isConstructor ? [signature] : ts.emptyArray;
+                type.constructSignatures = isConstructor ? [signature] : ts.emptyArray;
+                signature.isolatedSignatureType = type;
+            }
+            return signature.isolatedSignatureType;
+        }
+        function getIndexSymbol(symbol) {
+            return symbol.members.get("__index" /* Index */);
+        }
+        function getIndexDeclarationOfSymbol(symbol, kind) {
+            var syntaxKind = kind === 1 /* Number */ ? 134 /* NumberKeyword */ : 137 /* StringKeyword */;
+            var indexSymbol = getIndexSymbol(symbol);
+            if (indexSymbol) {
+                for (var _i = 0, _a = indexSymbol.declarations; _i < _a.length; _i++) {
+                    var decl = _a[_i];
+                    var node = ts.cast(decl, ts.isIndexSignatureDeclaration);
+                    if (node.parameters.length === 1) {
+                        var parameter = node.parameters[0];
+                        if (parameter.type && parameter.type.kind === syntaxKind) {
+                            return node;
+                        }
+                    }
+                }
+            }
+            return undefined;
+        }
+        function createIndexInfo(type, isReadonly, declaration) {
+            return { type: type, isReadonly: isReadonly, declaration: declaration };
+        }
+        function getIndexInfoOfSymbol(symbol, kind) {
+            var declaration = getIndexDeclarationOfSymbol(symbol, kind);
+            if (declaration) {
+                return createIndexInfo(declaration.type ? getTypeFromTypeNode(declaration.type) : anyType, ts.hasModifier(declaration, 64 /* Readonly */), declaration);
+            }
+            return undefined;
+        }
+        function getConstraintDeclaration(type) {
+            var decl = type.symbol && ts.getDeclarationOfKind(type.symbol, 148 /* TypeParameter */);
+            return decl && decl.constraint;
+        }
+        function getInferredTypeParameterConstraint(typeParameter) {
+            var inferences;
+            if (typeParameter.symbol) {
+                for (var _i = 0, _a = typeParameter.symbol.declarations; _i < _a.length; _i++) {
+                    var declaration = _a[_i];
+                    // When an 'infer T' declaration is immediately contained in a type reference node
+                    // (such as 'Foo<infer T>'), T's constraint is inferred from the constraint of the
+                    // corresponding type parameter in 'Foo'. When multiple 'infer T' declarations are
+                    // present, we form an intersection of the inferred constraint types.
+                    if (declaration.parent.kind === 172 /* InferType */ && declaration.parent.parent.kind === 162 /* TypeReference */) {
+                        var typeReference = declaration.parent.parent;
+                        var typeParameters = getTypeParametersForTypeReference(typeReference);
+                        if (typeParameters) {
+                            var index = typeReference.typeArguments.indexOf(declaration.parent);
+                            if (index < typeParameters.length) {
+                                var declaredConstraint = getConstraintOfTypeParameter(typeParameters[index]);
+                                if (declaredConstraint) {
+                                    // Type parameter constraints can reference other type parameters so
+                                    // constraints need to be instantiated. If instantiation produces the
+                                    // type parameter itself, we discard that inference. For example, in
+                                    //   type Foo<T extends string, U extends T> = [T, U];
+                                    //   type Bar<T> = T extends Foo<infer X, infer X> ? Foo<X, X> : T;
+                                    // the instantiated constraint for U is X, so we discard that inference.
+                                    var mapper = createTypeMapper(typeParameters, getEffectiveTypeArguments(typeReference, typeParameters));
+                                    var constraint = instantiateType(declaredConstraint, mapper);
+                                    if (constraint !== typeParameter) {
+                                        inferences = ts.append(inferences, constraint);
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+            return inferences && getIntersectionType(inferences);
+        }
+        function getConstraintFromTypeParameter(typeParameter) {
+            if (!typeParameter.constraint) {
+                if (typeParameter.target) {
+                    var targetConstraint = getConstraintOfTypeParameter(typeParameter.target);
+                    typeParameter.constraint = targetConstraint ? instantiateType(targetConstraint, typeParameter.mapper) : noConstraintType;
+                }
+                else {
+                    var constraintDeclaration = getConstraintDeclaration(typeParameter);
+                    typeParameter.constraint = constraintDeclaration ? getTypeFromTypeNode(constraintDeclaration) :
+                        getInferredTypeParameterConstraint(typeParameter) || noConstraintType;
+                }
+            }
+            return typeParameter.constraint === noConstraintType ? undefined : typeParameter.constraint;
+        }
+        function getParentSymbolOfTypeParameter(typeParameter) {
+            return getSymbolOfNode(ts.getDeclarationOfKind(typeParameter.symbol, 148 /* TypeParameter */).parent);
+        }
+        function getTypeListId(types) {
+            var result = "";
+            if (types) {
+                var length_3 = types.length;
+                var i = 0;
+                while (i < length_3) {
+                    var startId = types[i].id;
+                    var count = 1;
+                    while (i + count < length_3 && types[i + count].id === startId + count) {
+                        count++;
+                    }
+                    if (result.length) {
+                        result += ",";
+                    }
+                    result += startId;
+                    if (count > 1) {
+                        result += ":" + count;
+                    }
+                    i += count;
+                }
+            }
+            return result;
+        }
+        // This function is used to propagate certain flags when creating new object type references and union types.
+        // It is only necessary to do so if a constituent type might be the undefined type, the null type, the type
+        // of an object literal or the anyFunctionType. This is because there are operations in the type checker
+        // that care about the presence of such types at arbitrary depth in a containing type.
+        function getPropagatingFlagsOfTypes(types, excludeKinds) {
+            var result = 0;
+            for (var _i = 0, types_5 = types; _i < types_5.length; _i++) {
+                var type = types_5[_i];
+                if (!(type.flags & excludeKinds)) {
+                    result |= type.flags;
+                }
+            }
+            return result & 939524096 /* PropagatingFlags */;
+        }
+        function createTypeReference(target, typeArguments) {
+            var id = getTypeListId(typeArguments);
+            var type = target.instantiations.get(id);
+            if (!type) {
+                type = createObjectType(4 /* Reference */, target.symbol);
+                target.instantiations.set(id, type);
+                type.flags |= typeArguments ? getPropagatingFlagsOfTypes(typeArguments, /*excludeKinds*/ 0) : 0;
+                type.target = target;
+                type.typeArguments = typeArguments;
+            }
+            return type;
+        }
+        function cloneTypeReference(source) {
+            var type = createType(source.flags);
+            type.symbol = source.symbol;
+            type.objectFlags = source.objectFlags;
+            type.target = source.target;
+            type.typeArguments = source.typeArguments;
+            return type;
+        }
+        function getTypeReferenceArity(type) {
+            return ts.length(type.target.typeParameters);
+        }
+        /**
+         * Get type from type-reference that reference to class or interface
+         */
+        function getTypeFromClassOrInterfaceReference(node, symbol, typeArgs) {
+            var type = getDeclaredTypeOfSymbol(getMergedSymbol(symbol));
+            var typeParameters = type.localTypeParameters;
+            if (typeParameters) {
+                var numTypeArguments = ts.length(node.typeArguments);
+                var minTypeArgumentCount = getMinTypeArgumentCount(typeParameters);
+                var isJs = ts.isInJavaScriptFile(node);
+                var isJsImplicitAny = !noImplicitAny && isJs;
+                if (!isJsImplicitAny && (numTypeArguments < minTypeArgumentCount || numTypeArguments > typeParameters.length)) {
+                    var missingAugmentsTag = isJs && node.parent.kind !== 290 /* JSDocAugmentsTag */;
+                    var diag = minTypeArgumentCount === typeParameters.length
+                        ? missingAugmentsTag
+                            ? ts.Diagnostics.Expected_0_type_arguments_provide_these_with_an_extends_tag
+                            : ts.Diagnostics.Generic_type_0_requires_1_type_argument_s
+                        : missingAugmentsTag
+                            ? ts.Diagnostics.Expected_0_1_type_arguments_provide_these_with_an_extends_tag
+                            : ts.Diagnostics.Generic_type_0_requires_between_1_and_2_type_arguments;
+                    var typeStr = typeToString(type, /*enclosingDeclaration*/ undefined, 2 /* WriteArrayAsGenericType */);
+                    error(node, diag, typeStr, minTypeArgumentCount, typeParameters.length);
+                    if (!isJs) {
+                        // TODO: Adopt same permissive behavior in TS as in JS to reduce follow-on editing experience failures (requires editing fillMissingTypeArguments)
+                        return errorType;
+                    }
+                }
+                // In a type reference, the outer type parameters of the referenced class or interface are automatically
+                // supplied as type arguments and the type reference only specifies arguments for the local type parameters
+                // of the class or interface.
+                var typeArguments = ts.concatenate(type.outerTypeParameters, fillMissingTypeArguments(typeArgs, typeParameters, minTypeArgumentCount, isJs));
+                return createTypeReference(type, typeArguments);
+            }
+            return checkNoTypeArguments(node, symbol) ? type : errorType;
+        }
+        function getTypeAliasInstantiation(symbol, typeArguments) {
+            var type = getDeclaredTypeOfSymbol(symbol);
+            var links = getSymbolLinks(symbol);
+            var typeParameters = links.typeParameters;
+            var id = getTypeListId(typeArguments);
+            var instantiation = links.instantiations.get(id);
+            if (!instantiation) {
+                links.instantiations.set(id, instantiation = instantiateType(type, createTypeMapper(typeParameters, fillMissingTypeArguments(typeArguments, typeParameters, getMinTypeArgumentCount(typeParameters), ts.isInJavaScriptFile(symbol.valueDeclaration)))));
+            }
+            return instantiation;
+        }
+        /**
+         * Get type from reference to type alias. When a type alias is generic, the declared type of the type alias may include
+         * references to the type parameters of the alias. We replace those with the actual type arguments by instantiating the
+         * declared type. Instantiations are cached using the type identities of the type arguments as the key.
+         */
+        function getTypeFromTypeAliasReference(node, symbol, typeArguments) {
+            var type = getDeclaredTypeOfSymbol(symbol);
+            var typeParameters = getSymbolLinks(symbol).typeParameters;
+            if (typeParameters) {
+                var numTypeArguments = ts.length(node.typeArguments);
+                var minTypeArgumentCount = getMinTypeArgumentCount(typeParameters);
+                if (numTypeArguments < minTypeArgumentCount || numTypeArguments > typeParameters.length) {
+                    error(node, minTypeArgumentCount === typeParameters.length
+                        ? ts.Diagnostics.Generic_type_0_requires_1_type_argument_s
+                        : ts.Diagnostics.Generic_type_0_requires_between_1_and_2_type_arguments, symbolToString(symbol), minTypeArgumentCount, typeParameters.length);
+                    return errorType;
+                }
+                return getTypeAliasInstantiation(symbol, typeArguments);
+            }
+            return checkNoTypeArguments(node, symbol) ? type : errorType;
+        }
+        function getTypeReferenceName(node) {
+            switch (node.kind) {
+                case 162 /* TypeReference */:
+                    return node.typeName;
+                case 207 /* ExpressionWithTypeArguments */:
+                    // We only support expressions that are simple qualified names. For other
+                    // expressions this produces undefined.
+                    var expr = node.expression;
+                    if (ts.isEntityNameExpression(expr)) {
+                        return expr;
+                    }
+                // fall through;
+            }
+            return undefined;
+        }
+        function resolveTypeReferenceName(typeReferenceName, meaning) {
+            if (!typeReferenceName) {
+                return unknownSymbol;
+            }
+            return resolveEntityName(typeReferenceName, meaning) || unknownSymbol;
+        }
+        function getTypeReferenceType(node, symbol) {
+            var typeArguments = typeArgumentsFromTypeReferenceNode(node); // Do unconditionally so we mark type arguments as referenced.
+            if (symbol === unknownSymbol) {
+                return errorType;
+            }
+            var type = getTypeReferenceTypeWorker(node, symbol, typeArguments);
+            if (type) {
+                return type;
+            }
+            // Get type from reference to named type that cannot be generic (enum or type parameter)
+            var res = tryGetDeclaredTypeOfSymbol(symbol);
+            if (res) {
+                return checkNoTypeArguments(node, symbol) ?
+                    res.flags & 65536 /* TypeParameter */ ? getConstrainedTypeVariable(res, node) : res :
+                    errorType;
+            }
+            if (!(symbol.flags & 67216319 /* Value */ && isJSDocTypeReference(node))) {
+                return errorType;
+            }
+            var jsdocType = getJSDocTypeReference(node, symbol, typeArguments);
+            if (jsdocType) {
+                return jsdocType;
+            }
+            // Resolve the type reference as a Type for the purpose of reporting errors.
+            resolveTypeReferenceName(getTypeReferenceName(node), 67901928 /* Type */);
+            return getTypeOfSymbol(symbol);
+        }
+        /**
+         * A jsdoc TypeReference may have resolved to a value (as opposed to a type). If
+         * the symbol is a constructor function, return the inferred class type; otherwise,
+         * the type of this reference is just the type of the value we resolved to.
+         */
+        function getJSDocTypeReference(node, symbol, typeArguments) {
+            var assignedType = getAssignedClassType(symbol);
+            var valueType = getTypeOfSymbol(symbol);
+            var referenceType = valueType.symbol && valueType.symbol !== symbol && !isInferredClassType(valueType) && getTypeReferenceTypeWorker(node, valueType.symbol, typeArguments);
+            if (referenceType || assignedType) {
+                // TODO: GH#18217 (should the `|| assignedType` be at a lower precedence?)
+                return (referenceType && assignedType ? getIntersectionType([assignedType, referenceType]) : referenceType || assignedType);
+            }
+        }
+        function getTypeReferenceTypeWorker(node, symbol, typeArguments) {
+            if (symbol.flags & (32 /* Class */ | 64 /* Interface */)) {
+                if (symbol.valueDeclaration && ts.isBinaryExpression(symbol.valueDeclaration.parent)) {
+                    var jsdocType = getJSDocTypeReference(node, symbol, typeArguments);
+                    if (jsdocType) {
+                        return jsdocType;
+                    }
+                }
+                return getTypeFromClassOrInterfaceReference(node, symbol, typeArguments);
+            }
+            if (symbol.flags & 524288 /* TypeAlias */) {
+                return getTypeFromTypeAliasReference(node, symbol, typeArguments);
+            }
+            if (symbol.flags & 16 /* Function */ &&
+                isJSDocTypeReference(node) &&
+                (symbol.members || ts.getJSDocClassTag(symbol.valueDeclaration))) {
+                return getInferredClassType(symbol);
+            }
+        }
+        function getSubstitutionType(typeVariable, substitute) {
+            var result = createType(8388608 /* Substitution */);
+            result.typeVariable = typeVariable;
+            result.substitute = substitute;
+            return result;
+        }
+        function isUnaryTupleTypeNode(node) {
+            return node.kind === 168 /* TupleType */ && node.elementTypes.length === 1;
+        }
+        function getImpliedConstraint(typeVariable, checkNode, extendsNode) {
+            return isUnaryTupleTypeNode(checkNode) && isUnaryTupleTypeNode(extendsNode) ? getImpliedConstraint(typeVariable, checkNode.elementTypes[0], extendsNode.elementTypes[0]) :
+                getActualTypeVariable(getTypeFromTypeNode(checkNode)) === typeVariable ? getTypeFromTypeNode(extendsNode) :
+                    undefined;
+        }
+        function getConstrainedTypeVariable(typeVariable, node) {
+            var constraints;
+            while (node && !ts.isStatement(node) && node.kind !== 286 /* JSDocComment */) {
+                var parent = node.parent;
+                if (parent.kind === 171 /* ConditionalType */ && node === parent.trueType) {
+                    var constraint = getImpliedConstraint(typeVariable, parent.checkType, parent.extendsType);
+                    if (constraint) {
+                        constraints = ts.append(constraints, constraint);
+                    }
+                }
+                node = parent;
+            }
+            return constraints ? getSubstitutionType(typeVariable, getIntersectionType(ts.append(constraints, typeVariable))) : typeVariable;
+        }
+        function isJSDocTypeReference(node) {
+            return !!(node.flags & 2097152 /* JSDoc */) && node.kind === 162 /* TypeReference */;
+        }
+        function checkNoTypeArguments(node, symbol) {
+            if (node.typeArguments) {
+                error(node, ts.Diagnostics.Type_0_is_not_generic, symbol ? symbolToString(symbol) : node.typeName ? ts.declarationNameToString(node.typeName) : "(anonymous)");
+                return false;
+            }
+            return true;
+        }
+        function getIntendedTypeFromJSDocTypeReference(node) {
+            if (ts.isIdentifier(node.typeName)) {
+                var typeArgs = node.typeArguments;
+                switch (node.typeName.escapedText) {
+                    case "String":
+                        checkNoTypeArguments(node);
+                        return stringType;
+                    case "Number":
+                        checkNoTypeArguments(node);
+                        return numberType;
+                    case "Boolean":
+                        checkNoTypeArguments(node);
+                        return booleanType;
+                    case "Void":
+                        checkNoTypeArguments(node);
+                        return voidType;
+                    case "Undefined":
+                        checkNoTypeArguments(node);
+                        return undefinedType;
+                    case "Null":
+                        checkNoTypeArguments(node);
+                        return nullType;
+                    case "Function":
+                    case "function":
+                        checkNoTypeArguments(node);
+                        return globalFunctionType;
+                    case "Array":
+                    case "array":
+                        return !typeArgs || !typeArgs.length ? anyArrayType : undefined;
+                    case "Promise":
+                    case "promise":
+                        return !typeArgs || !typeArgs.length ? createPromiseType(anyType) : undefined;
+                    case "Object":
+                        if (typeArgs && typeArgs.length === 2) {
+                            if (ts.isJSDocIndexSignature(node)) {
+                                var indexed = getTypeFromTypeNode(typeArgs[0]);
+                                var target = getTypeFromTypeNode(typeArgs[1]);
+                                var index = createIndexInfo(target, /*isReadonly*/ false);
+                                return createAnonymousType(undefined, emptySymbols, ts.emptyArray, ts.emptyArray, indexed === stringType ? index : undefined, indexed === numberType ? index : undefined);
+                            }
+                            return anyType;
+                        }
+                        checkNoTypeArguments(node);
+                        return anyType;
+                }
+            }
+        }
+        function getTypeFromJSDocNullableTypeNode(node) {
+            var type = getTypeFromTypeNode(node.type);
+            return strictNullChecks ? getNullableType(type, 16384 /* Null */) : type;
+        }
+        function getTypeFromTypeReference(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                var symbol = void 0;
+                var type = void 0;
+                var meaning = 67901928 /* Type */;
+                if (isJSDocTypeReference(node)) {
+                    type = getIntendedTypeFromJSDocTypeReference(node);
+                    meaning |= 67216319 /* Value */;
+                }
+                if (!type) {
+                    symbol = resolveTypeReferenceName(getTypeReferenceName(node), meaning);
+                    type = getTypeReferenceType(node, symbol);
+                }
+                // Cache both the resolved symbol and the resolved type. The resolved symbol is needed in when we check the
+                // type reference in checkTypeReferenceNode.
+                links.resolvedSymbol = symbol;
+                links.resolvedType = type;
+            }
+            return links.resolvedType;
+        }
+        function typeArgumentsFromTypeReferenceNode(node) {
+            return ts.map(node.typeArguments, getTypeFromTypeNode);
+        }
+        function getTypeFromTypeQueryNode(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                // TypeScript 1.0 spec (April 2014): 3.6.3
+                // The expression is processed as an identifier expression (section 4.3)
+                // or property access expression(section 4.10),
+                // the widened type(section 3.9) of which becomes the result.
+                links.resolvedType = getWidenedType(checkExpression(node.exprName));
+            }
+            return links.resolvedType;
+        }
+        function getTypeOfGlobalSymbol(symbol, arity) {
+            function getTypeDeclaration(symbol) {
+                var declarations = symbol.declarations;
+                for (var _i = 0, declarations_3 = declarations; _i < declarations_3.length; _i++) {
+                    var declaration = declarations_3[_i];
+                    switch (declaration.kind) {
+                        case 235 /* ClassDeclaration */:
+                        case 236 /* InterfaceDeclaration */:
+                        case 238 /* EnumDeclaration */:
+                            return declaration;
+                    }
+                }
+            }
+            if (!symbol) {
+                return arity ? emptyGenericType : emptyObjectType;
+            }
+            var type = getDeclaredTypeOfSymbol(symbol);
+            if (!(type.flags & 131072 /* Object */)) {
+                error(getTypeDeclaration(symbol), ts.Diagnostics.Global_type_0_must_be_a_class_or_interface_type, ts.symbolName(symbol));
+                return arity ? emptyGenericType : emptyObjectType;
+            }
+            if (ts.length(type.typeParameters) !== arity) {
+                error(getTypeDeclaration(symbol), ts.Diagnostics.Global_type_0_must_have_1_type_parameter_s, ts.symbolName(symbol), arity);
+                return arity ? emptyGenericType : emptyObjectType;
+            }
+            return type;
+        }
+        function getGlobalValueSymbol(name, reportErrors) {
+            return getGlobalSymbol(name, 67216319 /* Value */, reportErrors ? ts.Diagnostics.Cannot_find_global_value_0 : undefined);
+        }
+        function getGlobalTypeSymbol(name, reportErrors) {
+            return getGlobalSymbol(name, 67901928 /* Type */, reportErrors ? ts.Diagnostics.Cannot_find_global_type_0 : undefined);
+        }
+        function getGlobalSymbol(name, meaning, diagnostic) {
+            // Don't track references for global symbols anyway, so value if `isReference` is arbitrary
+            return resolveName(undefined, name, meaning, diagnostic, name, /*isUse*/ false);
+        }
+        function getGlobalType(name, arity, reportErrors) {
+            var symbol = getGlobalTypeSymbol(name, reportErrors);
+            return symbol || reportErrors ? getTypeOfGlobalSymbol(symbol, arity) : undefined;
+        }
+        function getGlobalTypedPropertyDescriptorType() {
+            return deferredGlobalTypedPropertyDescriptorType || (deferredGlobalTypedPropertyDescriptorType = getGlobalType("TypedPropertyDescriptor", /*arity*/ 1, /*reportErrors*/ true)) || emptyGenericType;
+        }
+        function getGlobalTemplateStringsArrayType() {
+            return deferredGlobalTemplateStringsArrayType || (deferredGlobalTemplateStringsArrayType = getGlobalType("TemplateStringsArray", /*arity*/ 0, /*reportErrors*/ true)) || emptyObjectType;
+        }
+        function getGlobalImportMetaType() {
+            return deferredGlobalImportMetaType || (deferredGlobalImportMetaType = getGlobalType("ImportMeta", /*arity*/ 0, /*reportErrors*/ true)) || emptyObjectType;
+        }
+        function getGlobalESSymbolConstructorSymbol(reportErrors) {
+            return deferredGlobalESSymbolConstructorSymbol || (deferredGlobalESSymbolConstructorSymbol = getGlobalValueSymbol("Symbol", reportErrors));
+        }
+        function getGlobalESSymbolType(reportErrors) {
+            return deferredGlobalESSymbolType || (deferredGlobalESSymbolType = getGlobalType("Symbol", /*arity*/ 0, reportErrors)) || emptyObjectType;
+        }
+        function getGlobalPromiseType(reportErrors) {
+            return deferredGlobalPromiseType || (deferredGlobalPromiseType = getGlobalType("Promise", /*arity*/ 1, reportErrors)) || emptyGenericType;
+        }
+        function getGlobalPromiseConstructorSymbol(reportErrors) {
+            return deferredGlobalPromiseConstructorSymbol || (deferredGlobalPromiseConstructorSymbol = getGlobalValueSymbol("Promise", reportErrors));
+        }
+        function getGlobalPromiseConstructorLikeType(reportErrors) {
+            return deferredGlobalPromiseConstructorLikeType || (deferredGlobalPromiseConstructorLikeType = getGlobalType("PromiseConstructorLike", /*arity*/ 0, reportErrors)) || emptyObjectType;
+        }
+        function getGlobalAsyncIterableType(reportErrors) {
+            return deferredGlobalAsyncIterableType || (deferredGlobalAsyncIterableType = getGlobalType("AsyncIterable", /*arity*/ 1, reportErrors)) || emptyGenericType;
+        }
+        function getGlobalAsyncIteratorType(reportErrors) {
+            return deferredGlobalAsyncIteratorType || (deferredGlobalAsyncIteratorType = getGlobalType("AsyncIterator", /*arity*/ 1, reportErrors)) || emptyGenericType;
+        }
+        function getGlobalAsyncIterableIteratorType(reportErrors) {
+            return deferredGlobalAsyncIterableIteratorType || (deferredGlobalAsyncIterableIteratorType = getGlobalType("AsyncIterableIterator", /*arity*/ 1, reportErrors)) || emptyGenericType;
+        }
+        function getGlobalIterableType(reportErrors) {
+            return deferredGlobalIterableType || (deferredGlobalIterableType = getGlobalType("Iterable", /*arity*/ 1, reportErrors)) || emptyGenericType;
+        }
+        function getGlobalIteratorType(reportErrors) {
+            return deferredGlobalIteratorType || (deferredGlobalIteratorType = getGlobalType("Iterator", /*arity*/ 1, reportErrors)) || emptyGenericType;
+        }
+        function getGlobalIterableIteratorType(reportErrors) {
+            return deferredGlobalIterableIteratorType || (deferredGlobalIterableIteratorType = getGlobalType("IterableIterator", /*arity*/ 1, reportErrors)) || emptyGenericType;
+        }
+        function getGlobalTypeOrUndefined(name, arity) {
+            if (arity === void 0) { arity = 0; }
+            var symbol = getGlobalSymbol(name, 67901928 /* Type */, /*diagnostic*/ undefined);
+            return symbol && getTypeOfGlobalSymbol(symbol, arity);
+        }
+        function getGlobalExtractSymbol() {
+            return deferredGlobalExtractSymbol || (deferredGlobalExtractSymbol = getGlobalSymbol("Extract", 524288 /* TypeAlias */, ts.Diagnostics.Cannot_find_global_type_0)); // TODO: GH#18217
+        }
+        /**
+         * Instantiates a global type that is generic with some element type, and returns that instantiation.
+         */
+        function createTypeFromGenericGlobalType(genericGlobalType, typeArguments) {
+            return genericGlobalType !== emptyGenericType ? createTypeReference(genericGlobalType, typeArguments) : emptyObjectType;
+        }
+        function createTypedPropertyDescriptorType(propertyType) {
+            return createTypeFromGenericGlobalType(getGlobalTypedPropertyDescriptorType(), [propertyType]);
+        }
+        function createAsyncIterableType(iteratedType) {
+            return createTypeFromGenericGlobalType(getGlobalAsyncIterableType(/*reportErrors*/ true), [iteratedType]);
+        }
+        function createAsyncIterableIteratorType(iteratedType) {
+            return createTypeFromGenericGlobalType(getGlobalAsyncIterableIteratorType(/*reportErrors*/ true), [iteratedType]);
+        }
+        function createIterableType(iteratedType) {
+            return createTypeFromGenericGlobalType(getGlobalIterableType(/*reportErrors*/ true), [iteratedType]);
+        }
+        function createIterableIteratorType(iteratedType) {
+            return createTypeFromGenericGlobalType(getGlobalIterableIteratorType(/*reportErrors*/ true), [iteratedType]);
+        }
+        function createArrayType(elementType) {
+            return createTypeFromGenericGlobalType(globalArrayType, [elementType]);
+        }
+        function getTypeFromArrayTypeNode(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                links.resolvedType = createArrayType(getTypeFromTypeNode(node.elementType));
+            }
+            return links.resolvedType;
+        }
+        // We represent tuple types as type references to synthesized generic interface types created by
+        // this function. The types are of the form:
+        //
+        //   interface Tuple<T0, T1, T2, ...> extends Array<T0 | T1 | T2 | ...> { 0: T0, 1: T1, 2: T2, ... }
+        //
+        // Note that the generic type created by this function has no symbol associated with it. The same
+        // is true for each of the synthesized type parameters.
+        function createTupleTypeOfArity(arity) {
+            var typeParameters = [];
+            var properties = [];
+            for (var i = 0; i < arity; i++) {
+                var typeParameter = createType(65536 /* TypeParameter */);
+                typeParameters.push(typeParameter);
+                var property = createSymbol(4 /* Property */, "" + i);
+                property.type = typeParameter;
+                properties.push(property);
+            }
+            var lengthSymbol = createSymbol(4 /* Property */, "length");
+            lengthSymbol.type = getLiteralType(arity);
+            properties.push(lengthSymbol);
+            var type = createObjectType(8 /* Tuple */ | 4 /* Reference */);
+            type.typeParameters = typeParameters;
+            type.outerTypeParameters = undefined;
+            type.localTypeParameters = typeParameters;
+            type.instantiations = ts.createMap();
+            type.instantiations.set(getTypeListId(type.typeParameters), type);
+            type.target = type;
+            type.typeArguments = type.typeParameters;
+            type.thisType = createType(65536 /* TypeParameter */);
+            type.thisType.isThisType = true;
+            type.thisType.constraint = type;
+            type.declaredProperties = properties;
+            type.declaredCallSignatures = ts.emptyArray;
+            type.declaredConstructSignatures = ts.emptyArray;
+            type.declaredStringIndexInfo = undefined;
+            type.declaredNumberIndexInfo = undefined;
+            return type;
+        }
+        function getTupleTypeOfArity(arity) {
+            return tupleTypes[arity] || (tupleTypes[arity] = createTupleTypeOfArity(arity));
+        }
+        function createTupleType(elementTypes) {
+            return createTypeReference(getTupleTypeOfArity(elementTypes.length), elementTypes);
+        }
+        function getTypeFromTupleTypeNode(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                links.resolvedType = createTupleType(ts.map(node.elementTypes, getTypeFromTypeNode));
+            }
+            return links.resolvedType;
+        }
+        function getTypeId(type) {
+            return type.id;
+        }
+        function containsType(types, type) {
+            return ts.binarySearch(types, type, getTypeId, ts.compareValues) >= 0;
+        }
+        // Return true if the given intersection type contains
+        // more than one unit type or,
+        // an object type and a nullable type (null or undefined), or
+        // a string-like type and a type known to be non-string-like, or
+        // a number-like type and a type known to be non-number-like, or
+        // a symbol-like type and a type known to be non-symbol-like, or
+        // a void-like type and a type known to be non-void-like, or
+        // a non-primitive type and a type known to be primitive.
+        function isEmptyIntersectionType(type) {
+            var combined = 0;
+            for (var _i = 0, _a = type.types; _i < _a.length; _i++) {
+                var t = _a[_i];
+                if (t.flags & 27072 /* Unit */ && combined & 27072 /* Unit */) {
+                    return true;
+                }
+                combined |= t.flags;
+                if (combined & 24576 /* Nullable */ && combined & (131072 /* Object */ | 16777216 /* NonPrimitive */) ||
+                    combined & 16777216 /* NonPrimitive */ && combined & (16809468 /* DisjointDomains */ & ~16777216 /* NonPrimitive */) ||
+                    combined & 68 /* StringLike */ && combined & (16809468 /* DisjointDomains */ & ~68 /* StringLike */) ||
+                    combined & 168 /* NumberLike */ && combined & (16809468 /* DisjointDomains */ & ~168 /* NumberLike */) ||
+                    combined & 3072 /* ESSymbolLike */ && combined & (16809468 /* DisjointDomains */ & ~3072 /* ESSymbolLike */) ||
+                    combined & 12288 /* VoidLike */ && combined & (16809468 /* DisjointDomains */ & ~12288 /* VoidLike */)) {
+                    return true;
+                }
+            }
+            return false;
+        }
+        function addTypeToUnion(typeSet, includes, type) {
+            var flags = type.flags;
+            if (flags & 262144 /* Union */) {
+                return addTypesToUnion(typeSet, includes, type.types);
+            }
+            // We ignore 'never' types in unions. Likewise, we ignore intersections of unit types as they are
+            // another form of 'never' (in that they have an empty value domain). We could in theory turn
+            // intersections of unit types into 'never' upon construction, but deferring the reduction makes it
+            // easier to reason about their origin.
+            if (!(flags & 32768 /* Never */ || flags & 524288 /* Intersection */ && isEmptyIntersectionType(type))) {
+                includes |= flags & ~939524096 /* ConstructionFlags */;
+                if (flags & 3 /* AnyOrUnknown */) {
+                    if (type === wildcardType)
+                        includes |= 268435456 /* Wildcard */;
+                }
+                else if (!strictNullChecks && flags & 24576 /* Nullable */) {
+                    if (!(flags & 134217728 /* ContainsWideningType */))
+                        includes |= 134217728 /* NonWideningType */;
+                }
+                else {
+                    var len = typeSet.length;
+                    var index = len && type.id > typeSet[len - 1].id ? ~len : ts.binarySearch(typeSet, type, getTypeId, ts.compareValues);
+                    if (index < 0) {
+                        if (!(flags & 131072 /* Object */ && type.objectFlags & 16 /* Anonymous */ &&
+                            type.symbol && type.symbol.flags & (16 /* Function */ | 8192 /* Method */) && containsIdenticalType(typeSet, type))) {
+                            typeSet.splice(~index, 0, type);
+                        }
+                    }
+                }
+            }
+            return includes;
+        }
+        // Add the given types to the given type set. Order is preserved, duplicates are removed,
+        // and nested types of the given kind are flattened into the set.
+        function addTypesToUnion(typeSet, includes, types) {
+            for (var _i = 0, types_6 = types; _i < types_6.length; _i++) {
+                var type = types_6[_i];
+                includes = addTypeToUnion(typeSet, includes, type);
+            }
+            return includes;
+        }
+        function containsIdenticalType(types, type) {
+            for (var _i = 0, types_7 = types; _i < types_7.length; _i++) {
+                var t = types_7[_i];
+                if (isTypeIdenticalTo(t, type)) {
+                    return true;
+                }
+            }
+            return false;
+        }
+        function isSubtypeOfAny(source, targets) {
+            for (var _i = 0, targets_1 = targets; _i < targets_1.length; _i++) {
+                var target = targets_1[_i];
+                if (source !== target && isTypeSubtypeOf(source, target) && (!(ts.getObjectFlags(getTargetType(source)) & 1 /* Class */) ||
+                    !(ts.getObjectFlags(getTargetType(target)) & 1 /* Class */) ||
+                    isTypeDerivedFrom(source, target))) {
+                    return true;
+                }
+            }
+            return false;
+        }
+        function isSetOfLiteralsFromSameEnum(types) {
+            var first = types[0];
+            if (first.flags & 512 /* EnumLiteral */) {
+                var firstEnum = getParentOfSymbol(first.symbol);
+                for (var i = 1; i < types.length; i++) {
+                    var other = types[i];
+                    if (!(other.flags & 512 /* EnumLiteral */) || (firstEnum !== getParentOfSymbol(other.symbol))) {
+                        return false;
+                    }
+                }
+                return true;
+            }
+            return false;
+        }
+        function removeSubtypes(types) {
+            if (types.length === 0 || isSetOfLiteralsFromSameEnum(types)) {
+                return;
+            }
+            var i = types.length;
+            while (i > 0) {
+                i--;
+                if (isSubtypeOfAny(types[i], types)) {
+                    ts.orderedRemoveItemAt(types, i);
+                }
+            }
+        }
+        function removeRedundantLiteralTypes(types, includes) {
+            var i = types.length;
+            while (i > 0) {
+                i--;
+                var t = types[i];
+                var remove = t.flags & 64 /* StringLiteral */ && includes & 4 /* String */ ||
+                    t.flags & 128 /* NumberLiteral */ && includes & 8 /* Number */ ||
+                    t.flags & 2048 /* UniqueESSymbol */ && includes & 1024 /* ESSymbol */ ||
+                    t.flags & 192 /* StringOrNumberLiteral */ && t.flags & 33554432 /* FreshLiteral */ && containsType(types, t.regularType);
+                if (remove) {
+                    ts.orderedRemoveItemAt(types, i);
+                }
+            }
+        }
+        // We sort and deduplicate the constituent types based on object identity. If the subtypeReduction
+        // flag is specified we also reduce the constituent type set to only include types that aren't subtypes
+        // of other types. Subtype reduction is expensive for large union types and is possible only when union
+        // types are known not to circularly reference themselves (as is the case with union types created by
+        // expression constructs such as array literals and the || and ?: operators). Named types can
+        // circularly reference themselves and therefore cannot be subtype reduced during their declaration.
+        // For example, "type Item = string | (() => Item" is a named type that circularly references itself.
+        function getUnionType(types, unionReduction, aliasSymbol, aliasTypeArguments) {
+            if (unionReduction === void 0) { unionReduction = 1 /* Literal */; }
+            if (types.length === 0) {
+                return neverType;
+            }
+            if (types.length === 1) {
+                return types[0];
+            }
+            var typeSet = [];
+            var includes = addTypesToUnion(typeSet, 0, types);
+            if (includes & 3 /* AnyOrUnknown */) {
+                return includes & 1 /* Any */ ? includes & 268435456 /* Wildcard */ ? wildcardType : anyType : unknownType;
+            }
+            switch (unionReduction) {
+                case 1 /* Literal */:
+                    if (includes & 2240 /* StringOrNumberLiteralOrUnique */) {
+                        removeRedundantLiteralTypes(typeSet, includes);
+                    }
+                    break;
+                case 2 /* Subtype */:
+                    removeSubtypes(typeSet);
+                    break;
+            }
+            if (typeSet.length === 0) {
+                return includes & 16384 /* Null */ ? includes & 134217728 /* NonWideningType */ ? nullType : nullWideningType :
+                    includes & 8192 /* Undefined */ ? includes & 134217728 /* NonWideningType */ ? undefinedType : undefinedWideningType :
+                        neverType;
+            }
+            return getUnionTypeFromSortedList(typeSet, includes & 16749629 /* NotUnit */ ? 0 : 67108864 /* UnionOfUnitTypes */, aliasSymbol, aliasTypeArguments);
+        }
+        function getUnionTypePredicate(signatures) {
+            var first;
+            var types = [];
+            for (var _i = 0, signatures_2 = signatures; _i < signatures_2.length; _i++) {
+                var sig = signatures_2[_i];
+                var pred = getTypePredicateOfSignature(sig);
+                if (!pred) {
+                    continue;
+                }
+                if (first) {
+                    if (!typePredicateKindsMatch(first, pred)) {
+                        // No common type predicate.
+                        return undefined;
+                    }
+                }
+                else {
+                    first = pred;
+                }
+                types.push(pred.type);
+            }
+            if (!first) {
+                // No union signatures had a type predicate.
+                return undefined;
+            }
+            var unionType = getUnionType(types);
+            return ts.isIdentifierTypePredicate(first)
+                ? createIdentifierTypePredicate(first.parameterName, first.parameterIndex, unionType)
+                : createThisTypePredicate(unionType);
+        }
+        function typePredicateKindsMatch(a, b) {
+            return ts.isIdentifierTypePredicate(a)
+                ? ts.isIdentifierTypePredicate(b) && a.parameterIndex === b.parameterIndex
+                : !ts.isIdentifierTypePredicate(b);
+        }
+        // This function assumes the constituent type list is sorted and deduplicated.
+        function getUnionTypeFromSortedList(types, unionOfUnitTypes, aliasSymbol, aliasTypeArguments) {
+            if (types.length === 0) {
+                return neverType;
+            }
+            if (types.length === 1) {
+                return types[0];
+            }
+            var id = getTypeListId(types);
+            var type = unionTypes.get(id);
+            if (!type) {
+                var propagatedFlags = getPropagatingFlagsOfTypes(types, /*excludeKinds*/ 24576 /* Nullable */);
+                type = createType(262144 /* Union */ | propagatedFlags | unionOfUnitTypes);
+                unionTypes.set(id, type);
+                type.types = types;
+                /*
+                Note: This is the alias symbol (or lack thereof) that we see when we first encounter this union type.
+                For aliases of identical unions, eg `type T = A | B; type U = A | B`, the symbol of the first alias encountered is the aliasSymbol.
+                (In the language service, the order may depend on the order in which a user takes actions, such as hovering over symbols.)
+                It's important that we create equivalent union types only once, so that's an unfortunate side effect.
+                */
+                type.aliasSymbol = aliasSymbol;
+                type.aliasTypeArguments = aliasTypeArguments;
+            }
+            return type;
+        }
+        function getTypeFromUnionTypeNode(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                var aliasSymbol = getAliasSymbolForTypeNode(node);
+                links.resolvedType = getUnionType(ts.map(node.types, getTypeFromTypeNode), 1 /* Literal */, aliasSymbol, getTypeArgumentsForAliasSymbol(aliasSymbol));
+            }
+            return links.resolvedType;
+        }
+        function addTypeToIntersection(typeSet, includes, type) {
+            var flags = type.flags;
+            if (flags & 524288 /* Intersection */) {
+                return addTypesToIntersection(typeSet, includes, type.types);
+            }
+            if (ts.getObjectFlags(type) & 16 /* Anonymous */ && isEmptyObjectType(type)) {
+                includes |= 536870912 /* EmptyObject */;
+            }
+            else {
+                includes |= flags & ~939524096 /* ConstructionFlags */;
+                if (flags & 3 /* AnyOrUnknown */) {
+                    if (type === wildcardType)
+                        includes |= 268435456 /* Wildcard */;
+                }
+                else if ((strictNullChecks || !(flags & 24576 /* Nullable */)) && !ts.contains(typeSet, type) &&
+                    !(flags & 131072 /* Object */ && type.objectFlags & 16 /* Anonymous */ &&
+                        type.symbol && type.symbol.flags & (16 /* Function */ | 8192 /* Method */) &&
+                        containsIdenticalType(typeSet, type))) {
+                    typeSet.push(type);
+                }
+            }
+            return includes;
+        }
+        // Add the given types to the given type set. Order is preserved, freshness is removed from literal
+        // types, duplicates are removed, and nested types of the given kind are flattened into the set.
+        function addTypesToIntersection(typeSet, includes, types) {
+            for (var _i = 0, types_8 = types; _i < types_8.length; _i++) {
+                var type = types_8[_i];
+                includes = addTypeToIntersection(typeSet, includes, getRegularTypeOfLiteralType(type));
+            }
+            return includes;
+        }
+        function removeRedundantPrimitiveTypes(types, includes) {
+            var i = types.length;
+            while (i > 0) {
+                i--;
+                var t = types[i];
+                var remove = t.flags & 4 /* String */ && includes & 64 /* StringLiteral */ ||
+                    t.flags & 8 /* Number */ && includes & 128 /* NumberLiteral */ ||
+                    t.flags & 1024 /* ESSymbol */ && includes & 2048 /* UniqueESSymbol */;
+                if (remove) {
+                    ts.orderedRemoveItemAt(types, i);
+                }
+            }
+        }
+        // When intersecting unions of unit types we can simply intersect based on type identity.
+        // Here we remove all unions of unit types from the given list and replace them with a
+        // a single union containing an intersection of the unit types.
+        function intersectUnionsOfUnitTypes(types) {
+            var unionIndex = ts.findIndex(types, function (t) { return (t.flags & 67108864 /* UnionOfUnitTypes */) !== 0; });
+            var unionType = types[unionIndex];
+            var intersection = unionType.types;
+            var i = types.length - 1;
+            var _loop_6 = function () {
+                var t = types[i];
+                if (t.flags & 67108864 /* UnionOfUnitTypes */) {
+                    intersection = ts.filter(intersection, function (u) { return containsType(t.types, u); });
+                    ts.orderedRemoveItemAt(types, i);
+                }
+                i--;
+            };
+            while (i > unionIndex) {
+                _loop_6();
+            }
+            if (intersection === unionType.types) {
+                return false;
+            }
+            types[unionIndex] = getUnionTypeFromSortedList(intersection, unionType.flags & 67108864 /* UnionOfUnitTypes */);
+            return true;
+        }
+        // We normalize combinations of intersection and union types based on the distributive property of the '&'
+        // operator. Specifically, because X & (A | B) is equivalent to X & A | X & B, we can transform intersection
+        // types with union type constituents into equivalent union types with intersection type constituents and
+        // effectively ensure that union types are always at the top level in type representations.
+        //
+        // We do not perform structural deduplication on intersection types. Intersection types are created only by the &
+        // type operator and we can't reduce those because we want to support recursive intersection types. For example,
+        // a type alias of the form "type List<T> = T & { next: List<T> }" cannot be reduced during its declaration.
+        // Also, unlike union types, the order of the constituent types is preserved in order that overload resolution
+        // for intersections of types with signatures can be deterministic.
+        function getIntersectionType(types, aliasSymbol, aliasTypeArguments) {
+            var typeSet = [];
+            var includes = addTypesToIntersection(typeSet, 0, types);
+            if (includes & 32768 /* Never */) {
+                return neverType;
+            }
+            if (includes & 1 /* Any */) {
+                return includes & 268435456 /* Wildcard */ ? wildcardType : anyType;
+            }
+            if (!strictNullChecks && includes & 24576 /* Nullable */) {
+                return includes & 8192 /* Undefined */ ? undefinedType : nullType;
+            }
+            if (includes & 4 /* String */ && includes & 64 /* StringLiteral */ ||
+                includes & 8 /* Number */ && includes & 128 /* NumberLiteral */ ||
+                includes & 1024 /* ESSymbol */ && includes & 2048 /* UniqueESSymbol */) {
+                removeRedundantPrimitiveTypes(typeSet, includes);
+            }
+            if (includes & 536870912 /* EmptyObject */ && !(includes & 131072 /* Object */)) {
+                typeSet.push(emptyObjectType);
+            }
+            if (typeSet.length === 0) {
+                return unknownType;
+            }
+            if (typeSet.length === 1) {
+                return typeSet[0];
+            }
+            if (includes & 262144 /* Union */) {
+                if (includes & 67108864 /* UnionOfUnitTypes */ && intersectUnionsOfUnitTypes(typeSet)) {
+                    // When the intersection creates a reduced set (which might mean that *all* union types have
+                    // disappeared), we restart the operation to get a new set of combined flags. Once we have
+                    // reduced we'll never reduce again, so this occurs at most once.
+                    return getIntersectionType(typeSet, aliasSymbol, aliasTypeArguments);
+                }
+                // We are attempting to construct a type of the form X & (A | B) & Y. Transform this into a type of
+                // the form X & A & Y | X & B & Y and recursively reduce until no union type constituents remain.
+                var unionIndex_1 = ts.findIndex(typeSet, function (t) { return (t.flags & 262144 /* Union */) !== 0; });
+                var unionType = typeSet[unionIndex_1];
+                return getUnionType(ts.map(unionType.types, function (t) { return getIntersectionType(ts.replaceElement(typeSet, unionIndex_1, t)); }), 1 /* Literal */, aliasSymbol, aliasTypeArguments);
+            }
+            var id = getTypeListId(typeSet);
+            var type = intersectionTypes.get(id);
+            if (!type) {
+                var propagatedFlags = getPropagatingFlagsOfTypes(typeSet, /*excludeKinds*/ 24576 /* Nullable */);
+                type = createType(524288 /* Intersection */ | propagatedFlags);
+                intersectionTypes.set(id, type);
+                type.types = typeSet;
+                type.aliasSymbol = aliasSymbol; // See comment in `getUnionTypeFromSortedList`.
+                type.aliasTypeArguments = aliasTypeArguments;
+            }
+            return type;
+        }
+        function getTypeFromIntersectionTypeNode(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                var aliasSymbol = getAliasSymbolForTypeNode(node);
+                links.resolvedType = getIntersectionType(ts.map(node.types, getTypeFromTypeNode), aliasSymbol, getTypeArgumentsForAliasSymbol(aliasSymbol));
+            }
+            return links.resolvedType;
+        }
+        function createIndexType(type, stringsOnly) {
+            var result = createType(1048576 /* Index */);
+            result.type = type;
+            result.stringsOnly = stringsOnly;
+            return result;
+        }
+        function getIndexTypeForGenericType(type, stringsOnly) {
+            return stringsOnly ?
+                type.resolvedStringIndexType || (type.resolvedStringIndexType = createIndexType(type, /*stringsOnly*/ true)) :
+                type.resolvedIndexType || (type.resolvedIndexType = createIndexType(type, /*stringsOnly*/ false));
+        }
+        function getLiteralTypeFromPropertyName(prop, include) {
+            if (!(ts.getDeclarationModifierFlagsFromSymbol(prop) & 24 /* NonPublicAccessibilityModifier */)) {
+                var type = getLateBoundSymbol(prop).nameType;
+                if (!type && !ts.isKnownSymbol(prop)) {
+                    var name = ts.getNameOfDeclaration(prop.valueDeclaration);
+                    type = name && ts.isNumericLiteral(name) ? getLiteralType(+name.text) :
+                        name && name.kind === 147 /* ComputedPropertyName */ && ts.isNumericLiteral(name.expression) ? getLiteralType(+name.expression.text) :
+                            getLiteralType(ts.symbolName(prop));
+                }
+                if (type && type.flags & include) {
+                    return type;
+                }
+            }
+            return neverType;
+        }
+        function getLiteralTypeFromPropertyNames(type, include) {
+            return getUnionType(ts.map(getPropertiesOfType(type), function (t) { return getLiteralTypeFromPropertyName(t, include); }));
+        }
+        function getNonEnumNumberIndexInfo(type) {
+            var numberIndexInfo = getIndexInfoOfType(type, 1 /* Number */);
+            return numberIndexInfo !== enumNumberIndexInfo ? numberIndexInfo : undefined;
+        }
+        function getIndexType(type, stringsOnly) {
+            if (stringsOnly === void 0) { stringsOnly = keyofStringsOnly; }
+            return type.flags & 262144 /* Union */ ? getIntersectionType(ts.map(type.types, function (t) { return getIndexType(t, stringsOnly); })) :
+                type.flags & 524288 /* Intersection */ ? getUnionType(ts.map(type.types, function (t) { return getIndexType(t, stringsOnly); })) :
+                    maybeTypeOfKind(type, 14745600 /* InstantiableNonPrimitive */) ? getIndexTypeForGenericType(type, stringsOnly) :
+                        ts.getObjectFlags(type) & 32 /* Mapped */ ? getConstraintTypeFromMappedType(type) :
+                            type === wildcardType ? wildcardType :
+                                type.flags & 1 /* Any */ ? keyofConstraintType :
+                                    stringsOnly ? getIndexInfoOfType(type, 0 /* String */) ? stringType : getLiteralTypeFromPropertyNames(type, 64 /* StringLiteral */) :
+                                        getIndexInfoOfType(type, 0 /* String */) ? getUnionType([stringType, numberType, getLiteralTypeFromPropertyNames(type, 2048 /* UniqueESSymbol */)]) :
+                                            getNonEnumNumberIndexInfo(type) ? getUnionType([numberType, getLiteralTypeFromPropertyNames(type, 64 /* StringLiteral */ | 2048 /* UniqueESSymbol */)]) :
+                                                getLiteralTypeFromPropertyNames(type, 2240 /* StringOrNumberLiteralOrUnique */);
+        }
+        function getExtractStringType(type) {
+            if (keyofStringsOnly) {
+                return type;
+            }
+            var extractTypeAlias = getGlobalExtractSymbol();
+            return extractTypeAlias ? getTypeAliasInstantiation(extractTypeAlias, [type, stringType]) : stringType;
+        }
+        function getIndexTypeOrString(type) {
+            var indexType = getExtractStringType(getIndexType(type));
+            return indexType.flags & 32768 /* Never */ ? stringType : indexType;
+        }
+        function getTypeFromTypeOperatorNode(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                switch (node.operator) {
+                    case 128 /* KeyOfKeyword */:
+                        links.resolvedType = getIndexType(getTypeFromTypeNode(node.type));
+                        break;
+                    case 141 /* UniqueKeyword */:
+                        links.resolvedType = node.type.kind === 138 /* SymbolKeyword */
+                            ? getESSymbolLikeTypeForNode(ts.walkUpParenthesizedTypes(node.parent))
+                            : errorType;
+                        break;
+                }
+            }
+            return links.resolvedType; // TODO: GH#18217
+        }
+        function createIndexedAccessType(objectType, indexType) {
+            var type = createType(2097152 /* IndexedAccess */);
+            type.objectType = objectType;
+            type.indexType = indexType;
+            return type;
+        }
+        function getPropertyTypeForIndexType(objectType, indexType, accessNode, cacheSymbol) {
+            var accessExpression = accessNode && accessNode.kind === 186 /* ElementAccessExpression */ ? accessNode : undefined;
+            var propName = isTypeUsableAsLateBoundName(indexType) ? getLateBoundNameFromType(indexType) :
+                accessExpression && checkThatExpressionIsProperSymbolReference(accessExpression.argumentExpression, indexType, /*reportError*/ false) ?
+                    ts.getPropertyNameForKnownSymbolName(ts.idText(accessExpression.argumentExpression.name)) :
+                    undefined;
+            if (propName !== undefined) {
+                var prop = getPropertyOfType(objectType, propName);
+                if (prop) {
+                    if (accessExpression) {
+                        markPropertyAsReferenced(prop, accessExpression, /*isThisAccess*/ accessExpression.expression.kind === 99 /* ThisKeyword */);
+                        if (ts.isAssignmentTarget(accessExpression) && (isReferenceToReadonlyEntity(accessExpression, prop) || isReferenceThroughNamespaceImport(accessExpression))) {
+                            error(accessExpression.argumentExpression, ts.Diagnostics.Cannot_assign_to_0_because_it_is_a_constant_or_a_read_only_property, symbolToString(prop));
+                            return errorType;
+                        }
+                        if (cacheSymbol) {
+                            getNodeLinks(accessNode).resolvedSymbol = prop;
+                        }
+                    }
+                    return getTypeOfSymbol(prop);
+                }
+            }
+            if (!(indexType.flags & 24576 /* Nullable */) && isTypeAssignableToKind(indexType, 68 /* StringLike */ | 168 /* NumberLike */ | 3072 /* ESSymbolLike */)) {
+                if (isTypeAny(objectType)) {
+                    return objectType;
+                }
+                var indexInfo = isTypeAssignableToKind(indexType, 168 /* NumberLike */) && getIndexInfoOfType(objectType, 1 /* Number */) ||
+                    getIndexInfoOfType(objectType, 0 /* String */) ||
+                    undefined;
+                if (indexInfo) {
+                    if (accessNode && !isTypeAssignableToKind(indexType, 4 /* String */ | 8 /* Number */)) {
+                        var indexNode = accessNode.kind === 186 /* ElementAccessExpression */ ? accessNode.argumentExpression : accessNode.indexType;
+                        error(indexNode, ts.Diagnostics.Type_0_cannot_be_used_as_an_index_type, typeToString(indexType));
+                    }
+                    else if (accessExpression && indexInfo.isReadonly && (ts.isAssignmentTarget(accessExpression) || ts.isDeleteTarget(accessExpression))) {
+                        error(accessExpression, ts.Diagnostics.Index_signature_in_type_0_only_permits_reading, typeToString(objectType));
+                    }
+                    return indexInfo.type;
+                }
+                if (indexType.flags & 32768 /* Never */) {
+                    return neverType;
+                }
+                if (accessExpression && !isConstEnumObjectType(objectType)) {
+                    if (noImplicitAny && !compilerOptions.suppressImplicitAnyIndexErrors) {
+                        if (getIndexTypeOfType(objectType, 1 /* Number */)) {
+                            error(accessExpression.argumentExpression, ts.Diagnostics.Element_implicitly_has_an_any_type_because_index_expression_is_not_of_type_number);
+                        }
+                        else {
+                            error(accessExpression, ts.Diagnostics.Element_implicitly_has_an_any_type_because_type_0_has_no_index_signature, typeToString(objectType));
+                        }
+                    }
+                    return anyType;
+                }
+            }
+            if (accessNode) {
+                var indexNode = accessNode.kind === 186 /* ElementAccessExpression */ ? accessNode.argumentExpression : accessNode.indexType;
+                if (indexType.flags & (64 /* StringLiteral */ | 128 /* NumberLiteral */)) {
+                    error(indexNode, ts.Diagnostics.Property_0_does_not_exist_on_type_1, "" + indexType.value, typeToString(objectType));
+                }
+                else if (indexType.flags & (4 /* String */ | 8 /* Number */)) {
+                    error(indexNode, ts.Diagnostics.Type_0_has_no_matching_index_signature_for_type_1, typeToString(objectType), typeToString(indexType));
+                }
+                else {
+                    error(indexNode, ts.Diagnostics.Type_0_cannot_be_used_as_an_index_type, typeToString(indexType));
+                }
+            }
+            return errorType;
+        }
+        function isGenericObjectType(type) {
+            return maybeTypeOfKind(type, 14745600 /* InstantiableNonPrimitive */ | 134217728 /* GenericMappedType */);
+        }
+        function isGenericIndexType(type) {
+            return maybeTypeOfKind(type, 14745600 /* InstantiableNonPrimitive */ | 1048576 /* Index */);
+        }
+        // Return true if the given type is a non-generic object type with a string index signature and no
+        // other members.
+        function isStringIndexOnlyType(type) {
+            if (type.flags & 131072 /* Object */ && !isGenericMappedType(type)) {
+                var t = resolveStructuredTypeMembers(type);
+                return t.properties.length === 0 &&
+                    t.callSignatures.length === 0 && t.constructSignatures.length === 0 &&
+                    !!t.stringIndexInfo && !t.numberIndexInfo;
+            }
+            return false;
+        }
+        function isMappedTypeToNever(type) {
+            return !!(ts.getObjectFlags(type) & 32 /* Mapped */) && getTemplateTypeFromMappedType(type) === neverType;
+        }
+        function getSimplifiedType(type) {
+            return type.flags & 2097152 /* IndexedAccess */ ? getSimplifiedIndexedAccessType(type) : type;
+        }
+        // Transform an indexed access to a simpler form, if possible. Return the simpler form, or return
+        // the type itself if no transformation is possible.
+        function getSimplifiedIndexedAccessType(type) {
+            if (type.simplified) {
+                return type.simplified === circularConstraintType ? type : type.simplified;
+            }
+            type.simplified = circularConstraintType;
+            // We recursively simplify the object type as it may in turn be an indexed access type. For example, with
+            // '{ [P in T]: { [Q in U]: number } }[T][U]' we want to first simplify the inner indexed access type.
+            var objectType = getSimplifiedType(type.objectType);
+            if (objectType.flags & 524288 /* Intersection */ && isGenericObjectType(objectType)) {
+                // Given an indexed access type T[K], if T is an intersection containing one or more generic types and one or
+                // more object types with only a string index signature, e.g. '(U & V & { [x: string]: D })[K]', return a
+                // transformed type of the form '(U & V)[K] | D'. This allows us to properly reason about higher order indexed
+                // access types with default property values as expressed by D.
+                if (ts.some(objectType.types, isStringIndexOnlyType)) {
+                    var regularTypes = [];
+                    var stringIndexTypes = [];
+                    for (var _i = 0, _a = objectType.types; _i < _a.length; _i++) {
+                        var t = _a[_i];
+                        if (isStringIndexOnlyType(t)) {
+                            stringIndexTypes.push(getIndexTypeOfType(t, 0 /* String */));
+                        }
+                        else {
+                            regularTypes.push(t);
+                        }
+                    }
+                    return type.simplified = getUnionType([
+                        getSimplifiedType(getIndexedAccessType(getIntersectionType(regularTypes), type.indexType)),
+                        getIntersectionType(stringIndexTypes)
+                    ]);
+                }
+                // Given an indexed access type T[K], if T is an intersection containing one or more generic types and one or
+                // more mapped types with a template type `never`, '(U & V & { [P in T]: never })[K]', return a
+                // transformed type that removes the never-mapped type: '(U & V)[K]'. This mirrors what would happen
+                // eventually anyway, but it easier to reason about.
+                if (ts.some(objectType.types, isMappedTypeToNever)) {
+                    var nonNeverTypes = ts.filter(objectType.types, function (t) { return !isMappedTypeToNever(t); });
+                    return type.simplified = getSimplifiedType(getIndexedAccessType(getIntersectionType(nonNeverTypes), type.indexType));
+                }
+            }
+            // If the object type is a mapped type { [P in K]: E }, where K is generic, instantiate E using a mapper
+            // that substitutes the index type for P. For example, for an index access { [P in K]: Box<T[P]> }[X], we
+            // construct the type Box<T[X]>. We do not further simplify the result because mapped types can be recursive
+            // and we might never terminate.
+            if (isGenericMappedType(objectType)) {
+                return type.simplified = substituteIndexedMappedType(objectType, type);
+            }
+            if (objectType.flags & 65536 /* TypeParameter */) {
+                var constraint = getConstraintFromTypeParameter(objectType);
+                if (constraint && isGenericMappedType(constraint)) {
+                    return type.simplified = substituteIndexedMappedType(constraint, type);
+                }
+            }
+            return type.simplified = type;
+        }
+        function substituteIndexedMappedType(objectType, type) {
+            var mapper = createTypeMapper([getTypeParameterFromMappedType(objectType)], [type.indexType]);
+            var templateMapper = combineTypeMappers(objectType.mapper, mapper);
+            return instantiateType(getTemplateTypeFromMappedType(objectType), templateMapper);
+        }
+        function getIndexedAccessType(objectType, indexType, accessNode) {
+            if (objectType === wildcardType || indexType === wildcardType) {
+                return wildcardType;
+            }
+            // If the index type is generic, or if the object type is generic and doesn't originate in an expression,
+            // we are performing a higher-order index access where we cannot meaningfully access the properties of the
+            // object type. Note that for a generic T and a non-generic K, we eagerly resolve T[K] if it originates in
+            // an expression. This is to preserve backwards compatibility. For example, an element access 'this["foo"]'
+            // has always been resolved eagerly using the constraint type of 'this' at the given location.
+            if (isGenericIndexType(indexType) || !(accessNode && accessNode.kind === 186 /* ElementAccessExpression */) && isGenericObjectType(objectType)) {
+                if (objectType.flags & 3 /* AnyOrUnknown */) {
+                    return objectType;
+                }
+                // Defer the operation by creating an indexed access type.
+                var id = objectType.id + "," + indexType.id;
+                var type = indexedAccessTypes.get(id);
+                if (!type) {
+                    indexedAccessTypes.set(id, type = createIndexedAccessType(objectType, indexType));
+                }
+                return type;
+            }
+            // In the following we resolve T[K] to the type of the property in T selected by K.
+            // We treat boolean as different from other unions to improve errors;
+            // skipping straight to getPropertyTypeForIndexType gives errors with 'boolean' instead of 'true'.
+            var apparentObjectType = getApparentType(objectType);
+            if (indexType.flags & 262144 /* Union */ && !(indexType.flags & 16 /* Boolean */)) {
+                var propTypes = [];
+                for (var _i = 0, _a = indexType.types; _i < _a.length; _i++) {
+                    var t = _a[_i];
+                    var propType = getPropertyTypeForIndexType(apparentObjectType, t, accessNode, /*cacheSymbol*/ false);
+                    if (propType === errorType) {
+                        return errorType;
+                    }
+                    propTypes.push(propType);
+                }
+                return getUnionType(propTypes);
+            }
+            return getPropertyTypeForIndexType(apparentObjectType, indexType, accessNode, /*cacheSymbol*/ true);
+        }
+        function getTypeFromIndexedAccessTypeNode(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                var objectType = getTypeFromTypeNode(node.objectType);
+                var indexType = getTypeFromTypeNode(node.indexType);
+                var resolved = getIndexedAccessType(objectType, indexType, node);
+                links.resolvedType = resolved.flags & 2097152 /* IndexedAccess */ &&
+                    resolved.objectType === objectType &&
+                    resolved.indexType === indexType ?
+                    getConstrainedTypeVariable(resolved, node) : resolved;
+            }
+            return links.resolvedType;
+        }
+        function getTypeFromMappedTypeNode(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                var type = createObjectType(32 /* Mapped */, node.symbol);
+                type.declaration = node;
+                type.aliasSymbol = getAliasSymbolForTypeNode(node);
+                type.aliasTypeArguments = getTypeArgumentsForAliasSymbol(type.aliasSymbol);
+                links.resolvedType = type;
+                // Eagerly resolve the constraint type which forces an error if the constraint type circularly
+                // references itself through one or more type aliases.
+                getConstraintTypeFromMappedType(type);
+            }
+            return links.resolvedType;
+        }
+        function getActualTypeVariable(type) {
+            return type.flags & 8388608 /* Substitution */ ? type.typeVariable : type;
+        }
+        function getConditionalType(root, mapper) {
+            var checkType = instantiateType(root.checkType, mapper);
+            var extendsType = instantiateType(root.extendsType, mapper);
+            if (checkType === wildcardType || extendsType === wildcardType) {
+                return wildcardType;
+            }
+            // If this is a distributive conditional type and the check type is generic we need to defer
+            // resolution of the conditional type such that a later instantiation will properly distribute
+            // over union types.
+            var isDeferred = root.isDistributive && maybeTypeOfKind(checkType, 15794176 /* Instantiable */);
+            var combinedMapper;
+            if (root.inferTypeParameters) {
+                var context = createInferenceContext(root.inferTypeParameters, /*signature*/ undefined, 0 /* None */);
+                if (!isDeferred) {
+                    // We don't want inferences from constraints as they may cause us to eagerly resolve the
+                    // conditional type instead of deferring resolution. Also, we always want strict function
+                    // types rules (i.e. proper contravariance) for inferences.
+                    inferTypes(context.inferences, checkType, extendsType, 32 /* NoConstraints */ | 64 /* AlwaysStrict */);
+                }
+                combinedMapper = combineTypeMappers(mapper, context);
+            }
+            if (!isDeferred) {
+                if (extendsType.flags & 3 /* AnyOrUnknown */) {
+                    return instantiateType(root.trueType, mapper);
+                }
+                // Return union of trueType and falseType for 'any' since it matches anything
+                if (checkType.flags & 1 /* Any */) {
+                    return getUnionType([instantiateType(root.trueType, combinedMapper || mapper), instantiateType(root.falseType, mapper)]);
+                }
+                // Instantiate the extends type including inferences for 'infer T' type parameters
+                var inferredExtendsType = combinedMapper ? instantiateType(root.extendsType, combinedMapper) : extendsType;
+                // Return falseType for a definitely false extends check. We check an instantations of the two
+                // types with type parameters mapped to the wildcard type, the most permissive instantiations
+                // possible (the wildcard type is assignable to and from all types). If those are not related,
+                // then no instatiations will be and we can just return the false branch type.
+                if (!isTypeAssignableTo(getWildcardInstantiation(checkType), getWildcardInstantiation(inferredExtendsType))) {
+                    return instantiateType(root.falseType, mapper);
+                }
+                // Return trueType for a definitely true extends check. The definitely assignable relation excludes
+                // type variable constraints from consideration. Without the definitely assignable relation, the type
+                //   type Foo<T extends { x: any }> = T extends { x: string } ? string : number
+                // would immediately resolve to 'string' instead of being deferred.
+                if (checkTypeRelatedTo(checkType, inferredExtendsType, definitelyAssignableRelation, /*errorNode*/ undefined)) {
+                    return instantiateType(root.trueType, combinedMapper || mapper);
+                }
+            }
+            // Return a deferred type for a check that is neither definitely true nor definitely false
+            var erasedCheckType = getActualTypeVariable(checkType);
+            var result = createType(4194304 /* Conditional */);
+            result.root = root;
+            result.checkType = erasedCheckType;
+            result.extendsType = extendsType;
+            result.mapper = mapper;
+            result.combinedMapper = combinedMapper;
+            result.aliasSymbol = root.aliasSymbol;
+            result.aliasTypeArguments = instantiateTypes(root.aliasTypeArguments, mapper); // TODO: GH#18217
+            return result;
+        }
+        function getTrueTypeFromConditionalType(type) {
+            return type.resolvedTrueType || (type.resolvedTrueType = instantiateType(type.root.trueType, type.mapper));
+        }
+        function getFalseTypeFromConditionalType(type) {
+            return type.resolvedFalseType || (type.resolvedFalseType = instantiateType(type.root.falseType, type.mapper));
+        }
+        function getInferTypeParameters(node) {
+            var result;
+            if (node.locals) {
+                node.locals.forEach(function (symbol) {
+                    if (symbol.flags & 262144 /* TypeParameter */) {
+                        result = ts.append(result, getDeclaredTypeOfSymbol(symbol));
+                    }
+                });
+            }
+            return result;
+        }
+        function isPossiblyReferencedInConditionalType(tp, node) {
+            if (isTypeParameterPossiblyReferenced(tp, node)) {
+                return true;
+            }
+            while (node) {
+                if (node.kind === 171 /* ConditionalType */) {
+                    if (isTypeParameterPossiblyReferenced(tp, node.extendsType)) {
+                        return true;
+                    }
+                }
+                node = node.parent;
+            }
+            return false;
+        }
+        function getTypeFromConditionalTypeNode(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                var checkType = getTypeFromTypeNode(node.checkType);
+                var aliasSymbol = getAliasSymbolForTypeNode(node);
+                var aliasTypeArguments = getTypeArgumentsForAliasSymbol(aliasSymbol);
+                var allOuterTypeParameters = getOuterTypeParameters(node, /*includeThisTypes*/ true);
+                var outerTypeParameters = aliasTypeArguments ? allOuterTypeParameters : ts.filter(allOuterTypeParameters, function (tp) { return isPossiblyReferencedInConditionalType(tp, node); });
+                var root = {
+                    node: node,
+                    checkType: checkType,
+                    extendsType: getTypeFromTypeNode(node.extendsType),
+                    trueType: getTypeFromTypeNode(node.trueType),
+                    falseType: getTypeFromTypeNode(node.falseType),
+                    isDistributive: !!(checkType.flags & 65536 /* TypeParameter */),
+                    inferTypeParameters: getInferTypeParameters(node),
+                    outerTypeParameters: outerTypeParameters,
+                    instantiations: undefined,
+                    aliasSymbol: aliasSymbol,
+                    aliasTypeArguments: aliasTypeArguments
+                };
+                links.resolvedType = getConditionalType(root, /*mapper*/ undefined);
+                if (outerTypeParameters) {
+                    root.instantiations = ts.createMap();
+                    root.instantiations.set(getTypeListId(outerTypeParameters), links.resolvedType);
+                }
+            }
+            return links.resolvedType;
+        }
+        function getTypeFromInferTypeNode(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                links.resolvedType = getDeclaredTypeOfTypeParameter(getSymbolOfNode(node.typeParameter));
+            }
+            return links.resolvedType;
+        }
+        function getIdentifierChain(node) {
+            if (ts.isIdentifier(node)) {
+                return [node];
+            }
+            else {
+                return ts.append(getIdentifierChain(node.left), node.right);
+            }
+        }
+        function getTypeFromImportTypeNode(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                if (node.isTypeOf && node.typeArguments) { // Only the non-typeof form can make use of type arguments
+                    error(node, ts.Diagnostics.Type_arguments_cannot_be_used_here);
+                    links.resolvedSymbol = unknownSymbol;
+                    return links.resolvedType = errorType;
+                }
+                if (!ts.isLiteralImportTypeNode(node)) {
+                    error(node.argument, ts.Diagnostics.String_literal_expected);
+                    links.resolvedSymbol = unknownSymbol;
+                    return links.resolvedType = errorType;
+                }
+                var argumentType = getTypeFromTypeNode(node.argument);
+                var targetMeaning = node.isTypeOf ? 67216319 /* Value */ : 67901928 /* Type */;
+                // TODO: Future work: support unions/generics/whatever via a deferred import-type
+                var moduleName = argumentType.value;
+                var innerModuleSymbol = resolveExternalModule(node, moduleName, ts.Diagnostics.Cannot_find_module_0, node, /*isForAugmentation*/ false);
+                if (!innerModuleSymbol) {
+                    links.resolvedSymbol = unknownSymbol;
+                    return links.resolvedType = errorType;
+                }
+                var moduleSymbol_1 = resolveExternalModuleSymbol(innerModuleSymbol, /*dontResolveAlias*/ false);
+                if (!ts.nodeIsMissing(node.qualifier)) {
+                    var nameStack = getIdentifierChain(node.qualifier);
+                    var currentNamespace = moduleSymbol_1;
+                    var current = void 0;
+                    while (current = nameStack.shift()) {
+                        var meaning = nameStack.length ? 1920 /* Namespace */ : targetMeaning;
+                        var next = getSymbol(getExportsOfSymbol(getMergedSymbol(resolveSymbol(currentNamespace))), current.escapedText, meaning);
+                        if (!next) {
+                            error(current, ts.Diagnostics.Namespace_0_has_no_exported_member_1, getFullyQualifiedName(currentNamespace), ts.declarationNameToString(current));
+                            return links.resolvedType = errorType;
+                        }
+                        getNodeLinks(current).resolvedSymbol = next;
+                        getNodeLinks(current.parent).resolvedSymbol = next;
+                        currentNamespace = next;
+                    }
+                    resolveImportSymbolType(node, links, currentNamespace, targetMeaning);
+                }
+                else {
+                    if (moduleSymbol_1.flags & targetMeaning) {
+                        resolveImportSymbolType(node, links, moduleSymbol_1, targetMeaning);
+                    }
+                    else {
+                        error(node, targetMeaning === 67216319 /* Value */ ? ts.Diagnostics.Module_0_does_not_refer_to_a_value_but_is_used_as_a_value_here : ts.Diagnostics.Module_0_does_not_refer_to_a_type_but_is_used_as_a_type_here, moduleName);
+                        links.resolvedSymbol = unknownSymbol;
+                        links.resolvedType = errorType;
+                    }
+                }
+            }
+            return links.resolvedType; // TODO: GH#18217
+        }
+        function resolveImportSymbolType(node, links, symbol, meaning) {
+            var resolvedSymbol = resolveSymbol(symbol);
+            links.resolvedSymbol = resolvedSymbol;
+            if (meaning === 67216319 /* Value */) {
+                return links.resolvedType = getTypeOfSymbol(symbol); // intentionally doesn't use resolved symbol so type is cached as expected on the alias
+            }
+            else {
+                return links.resolvedType = getTypeReferenceType(node, resolvedSymbol); // getTypeReferenceType doesn't handle aliases - it must get the resolved symbol
+            }
+        }
+        function getTypeFromTypeLiteralOrFunctionOrConstructorTypeNode(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                // Deferred resolution of members is handled by resolveObjectTypeMembers
+                var aliasSymbol = getAliasSymbolForTypeNode(node);
+                if (getMembersOfSymbol(node.symbol).size === 0 && !aliasSymbol) {
+                    links.resolvedType = emptyTypeLiteralType;
+                }
+                else {
+                    var type = createObjectType(16 /* Anonymous */, node.symbol);
+                    type.aliasSymbol = aliasSymbol;
+                    type.aliasTypeArguments = getTypeArgumentsForAliasSymbol(aliasSymbol);
+                    if (ts.isJSDocTypeLiteral(node) && node.isArrayType) {
+                        type = createArrayType(type);
+                    }
+                    links.resolvedType = type;
+                }
+            }
+            return links.resolvedType;
+        }
+        function getAliasSymbolForTypeNode(node) {
+            return ts.isTypeAlias(node.parent) ? getSymbolOfNode(node.parent) : undefined;
+        }
+        function getTypeArgumentsForAliasSymbol(symbol) {
+            return symbol ? getLocalTypeParametersOfClassOrInterfaceOrTypeAlias(symbol) : undefined;
+        }
+        /**
+         * Since the source of spread types are object literals, which are not binary,
+         * this function should be called in a left folding style, with left = previous result of getSpreadType
+         * and right = the new element to be spread.
+         */
+        function getSpreadType(left, right, symbol, typeFlags, objectFlags) {
+            if (left.flags & 1 /* Any */ || right.flags & 1 /* Any */) {
+                return anyType;
+            }
+            if (left.flags & 2 /* Unknown */ || right.flags & 2 /* Unknown */) {
+                return unknownType;
+            }
+            if (left.flags & 32768 /* Never */) {
+                return right;
+            }
+            if (right.flags & 32768 /* Never */) {
+                return left;
+            }
+            if (left.flags & 262144 /* Union */) {
+                return mapType(left, function (t) { return getSpreadType(t, right, symbol, typeFlags, objectFlags); });
+            }
+            if (right.flags & 262144 /* Union */) {
+                return mapType(right, function (t) { return getSpreadType(left, t, symbol, typeFlags, objectFlags); });
+            }
+            if (right.flags & (272 /* BooleanLike */ | 168 /* NumberLike */ | 68 /* StringLike */ | 544 /* EnumLike */ | 16777216 /* NonPrimitive */ | 1048576 /* Index */)) {
+                return left;
+            }
+            var members = ts.createSymbolTable();
+            var skippedPrivateMembers = ts.createUnderscoreEscapedMap();
+            var stringIndexInfo;
+            var numberIndexInfo;
+            if (left === emptyObjectType) {
+                // for the first spread element, left === emptyObjectType, so take the right's string indexer
+                stringIndexInfo = getIndexInfoOfType(right, 0 /* String */);
+                numberIndexInfo = getIndexInfoOfType(right, 1 /* Number */);
+            }
+            else {
+                stringIndexInfo = unionSpreadIndexInfos(getIndexInfoOfType(left, 0 /* String */), getIndexInfoOfType(right, 0 /* String */));
+                numberIndexInfo = unionSpreadIndexInfos(getIndexInfoOfType(left, 1 /* Number */), getIndexInfoOfType(right, 1 /* Number */));
+            }
+            for (var _i = 0, _a = getPropertiesOfType(right); _i < _a.length; _i++) {
+                var rightProp = _a[_i];
+                // we approximate own properties as non-methods plus methods that are inside the object literal
+                var isSetterWithoutGetter = rightProp.flags & 65536 /* SetAccessor */ && !(rightProp.flags & 32768 /* GetAccessor */);
+                if (ts.getDeclarationModifierFlagsFromSymbol(rightProp) & (8 /* Private */ | 16 /* Protected */)) {
+                    skippedPrivateMembers.set(rightProp.escapedName, true);
+                }
+                else if (!isClassMethod(rightProp) && !isSetterWithoutGetter) {
+                    members.set(rightProp.escapedName, getNonReadonlySymbol(rightProp));
+                }
+            }
+            for (var _b = 0, _c = getPropertiesOfType(left); _b < _c.length; _b++) {
+                var leftProp = _c[_b];
+                if (leftProp.flags & 65536 /* SetAccessor */ && !(leftProp.flags & 32768 /* GetAccessor */)
+                    || skippedPrivateMembers.has(leftProp.escapedName)
+                    || isClassMethod(leftProp)) {
+                    continue;
+                }
+                if (members.has(leftProp.escapedName)) {
+                    var rightProp = members.get(leftProp.escapedName);
+                    var rightType = getTypeOfSymbol(rightProp);
+                    if (rightProp.flags & 16777216 /* Optional */) {
+                        var declarations = ts.concatenate(leftProp.declarations, rightProp.declarations);
+                        var flags = 4 /* Property */ | (leftProp.flags & 16777216 /* Optional */);
+                        var result = createSymbol(flags, leftProp.escapedName);
+                        result.type = getUnionType([getTypeOfSymbol(leftProp), getTypeWithFacts(rightType, 131072 /* NEUndefined */)]);
+                        result.leftSpread = leftProp;
+                        result.rightSpread = rightProp;
+                        result.declarations = declarations;
+                        result.nameType = leftProp.nameType;
+                        members.set(leftProp.escapedName, result);
+                    }
+                }
+                else {
+                    members.set(leftProp.escapedName, getNonReadonlySymbol(leftProp));
+                }
+            }
+            var spread = createAnonymousType(symbol, members, ts.emptyArray, ts.emptyArray, getNonReadonlyIndexSignature(stringIndexInfo), getNonReadonlyIndexSignature(numberIndexInfo));
+            spread.flags |= typeFlags | 268435456 /* ContainsObjectLiteral */;
+            spread.objectFlags |= objectFlags | (128 /* ObjectLiteral */ | 1024 /* ContainsSpread */);
+            return spread;
+        }
+        function getNonReadonlySymbol(prop) {
+            if (!isReadonlySymbol(prop)) {
+                return prop;
+            }
+            var flags = 4 /* Property */ | (prop.flags & 16777216 /* Optional */);
+            var result = createSymbol(flags, prop.escapedName);
+            result.type = getTypeOfSymbol(prop);
+            result.declarations = prop.declarations;
+            result.nameType = prop.nameType;
+            result.syntheticOrigin = prop;
+            return result;
+        }
+        function getNonReadonlyIndexSignature(index) {
+            if (index && index.isReadonly) {
+                return createIndexInfo(index.type, /*isReadonly*/ false, index.declaration);
+            }
+            return index;
+        }
+        function isClassMethod(prop) {
+            return prop.flags & 8192 /* Method */ && ts.find(prop.declarations, function (decl) { return ts.isClassLike(decl.parent); });
+        }
+        function createLiteralType(flags, value, symbol) {
+            var type = createType(flags);
+            type.symbol = symbol;
+            type.value = value;
+            return type;
+        }
+        function getFreshTypeOfLiteralType(type) {
+            if (type.flags & 192 /* StringOrNumberLiteral */ && !(type.flags & 33554432 /* FreshLiteral */)) {
+                if (!type.freshType) {
+                    var freshType = createLiteralType(type.flags | 33554432 /* FreshLiteral */, type.value, type.symbol);
+                    freshType.regularType = type;
+                    type.freshType = freshType;
+                }
+                return type.freshType;
+            }
+            return type;
+        }
+        function getRegularTypeOfLiteralType(type) {
+            return type.flags & 192 /* StringOrNumberLiteral */ && type.flags & 33554432 /* FreshLiteral */ ? type.regularType :
+                type.flags & 262144 /* Union */ ? getUnionType(ts.sameMap(type.types, getRegularTypeOfLiteralType)) :
+                    type;
+        }
+        function getLiteralType(value, enumId, symbol) {
+            // We store all literal types in a single map with keys of the form '#NNN' and '@SSS',
+            // where NNN is the text representation of a numeric literal and SSS are the characters
+            // of a string literal. For literal enum members we use 'EEE#NNN' and 'EEE@SSS', where
+            // EEE is a unique id for the containing enum type.
+            var qualifier = typeof value === "number" ? "#" : "@";
+            var key = enumId ? enumId + qualifier + value : qualifier + value;
+            var type = literalTypes.get(key);
+            if (!type) {
+                var flags = (typeof value === "number" ? 128 /* NumberLiteral */ : 64 /* StringLiteral */) | (enumId ? 512 /* EnumLiteral */ : 0);
+                literalTypes.set(key, type = createLiteralType(flags, value, symbol));
+            }
+            return type;
+        }
+        function getTypeFromLiteralTypeNode(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                links.resolvedType = getRegularTypeOfLiteralType(checkExpression(node.literal));
+            }
+            return links.resolvedType;
+        }
+        function createUniqueESSymbolType(symbol) {
+            var type = createType(2048 /* UniqueESSymbol */);
+            type.symbol = symbol;
+            return type;
+        }
+        function getESSymbolLikeTypeForNode(node) {
+            if (ts.isValidESSymbolDeclaration(node)) {
+                var symbol = getSymbolOfNode(node);
+                var links = getSymbolLinks(symbol);
+                return links.uniqueESSymbolType || (links.uniqueESSymbolType = createUniqueESSymbolType(symbol));
+            }
+            return esSymbolType;
+        }
+        function getThisType(node) {
+            var container = ts.getThisContainer(node, /*includeArrowFunctions*/ false);
+            var parent = container && container.parent;
+            if (parent && (ts.isClassLike(parent) || parent.kind === 236 /* InterfaceDeclaration */)) {
+                if (!ts.hasModifier(container, 32 /* Static */) &&
+                    (container.kind !== 155 /* Constructor */ || ts.isNodeDescendantOf(node, container.body))) {
+                    return getDeclaredTypeOfClassOrInterface(getSymbolOfNode(parent)).thisType;
+                }
+            }
+            error(node, ts.Diagnostics.A_this_type_is_available_only_in_a_non_static_member_of_a_class_or_interface);
+            return errorType;
+        }
+        function getTypeFromThisTypeNode(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                links.resolvedType = getThisType(node);
+            }
+            return links.resolvedType;
+        }
+        function getTypeFromTypeNode(node) {
+            switch (node.kind) {
+                case 119 /* AnyKeyword */:
+                case 279 /* JSDocAllType */:
+                case 280 /* JSDocUnknownType */:
+                    return anyType;
+                case 142 /* UnknownKeyword */:
+                    return unknownType;
+                case 137 /* StringKeyword */:
+                    return stringType;
+                case 134 /* NumberKeyword */:
+                    return numberType;
+                case 122 /* BooleanKeyword */:
+                    return booleanType;
+                case 138 /* SymbolKeyword */:
+                    return esSymbolType;
+                case 105 /* VoidKeyword */:
+                    return voidType;
+                case 140 /* UndefinedKeyword */:
+                    return undefinedType;
+                case 95 /* NullKeyword */:
+                    return nullType;
+                case 131 /* NeverKeyword */:
+                    return neverType;
+                case 135 /* ObjectKeyword */:
+                    return node.flags & 65536 /* JavaScriptFile */ ? anyType : nonPrimitiveType;
+                case 174 /* ThisType */:
+                case 99 /* ThisKeyword */:
+                    return getTypeFromThisTypeNode(node);
+                case 178 /* LiteralType */:
+                    return getTypeFromLiteralTypeNode(node);
+                case 162 /* TypeReference */:
+                    return getTypeFromTypeReference(node);
+                case 161 /* TypePredicate */:
+                    return booleanType;
+                case 207 /* ExpressionWithTypeArguments */:
+                    return getTypeFromTypeReference(node);
+                case 165 /* TypeQuery */:
+                    return getTypeFromTypeQueryNode(node);
+                case 167 /* ArrayType */:
+                    return getTypeFromArrayTypeNode(node);
+                case 168 /* TupleType */:
+                    return getTypeFromTupleTypeNode(node);
+                case 169 /* UnionType */:
+                    return getTypeFromUnionTypeNode(node);
+                case 170 /* IntersectionType */:
+                    return getTypeFromIntersectionTypeNode(node);
+                case 281 /* JSDocNullableType */:
+                    return getTypeFromJSDocNullableTypeNode(node);
+                case 283 /* JSDocOptionalType */:
+                    return addOptionality(getTypeFromTypeNode(node.type));
+                case 173 /* ParenthesizedType */:
+                case 282 /* JSDocNonNullableType */:
+                case 278 /* JSDocTypeExpression */:
+                    return getTypeFromTypeNode(node.type);
+                case 285 /* JSDocVariadicType */:
+                    return getTypeFromJSDocVariadicType(node);
+                case 163 /* FunctionType */:
+                case 164 /* ConstructorType */:
+                case 166 /* TypeLiteral */:
+                case 287 /* JSDocTypeLiteral */:
+                case 284 /* JSDocFunctionType */:
+                case 288 /* JSDocSignature */:
+                    return getTypeFromTypeLiteralOrFunctionOrConstructorTypeNode(node);
+                case 175 /* TypeOperator */:
+                    return getTypeFromTypeOperatorNode(node);
+                case 176 /* IndexedAccessType */:
+                    return getTypeFromIndexedAccessTypeNode(node);
+                case 177 /* MappedType */:
+                    return getTypeFromMappedTypeNode(node);
+                case 171 /* ConditionalType */:
+                    return getTypeFromConditionalTypeNode(node);
+                case 172 /* InferType */:
+                    return getTypeFromInferTypeNode(node);
+                case 179 /* ImportType */:
+                    return getTypeFromImportTypeNode(node);
+                // This function assumes that an identifier or qualified name is a type expression
+                // Callers should first ensure this by calling isTypeNode
+                case 71 /* Identifier */:
+                case 146 /* QualifiedName */:
+                    var symbol = getSymbolAtLocation(node);
+                    return (symbol && getDeclaredTypeOfSymbol(symbol)); // TODO: GH#18217
+                default:
+                    return errorType;
+            }
+        }
+        function instantiateList(items, mapper, instantiator) {
+            if (items && items.length) {
+                for (var i = 0; i < items.length; i++) {
+                    var item = items[i];
+                    var mapped = instantiator(item, mapper);
+                    if (item !== mapped) {
+                        var result = i === 0 ? [] : items.slice(0, i);
+                        result.push(mapped);
+                        for (i++; i < items.length; i++) {
+                            result.push(instantiator(items[i], mapper));
+                        }
+                        return result;
+                    }
+                }
+            }
+            return items;
+        }
+        function instantiateTypes(types, mapper) {
+            return instantiateList(types, mapper, instantiateType);
+        }
+        function instantiateSignatures(signatures, mapper) {
+            return instantiateList(signatures, mapper, instantiateSignature);
+        }
+        function makeUnaryTypeMapper(source, target) {
+            return function (t) { return t === source ? target : t; };
+        }
+        function makeBinaryTypeMapper(source1, target1, source2, target2) {
+            return function (t) { return t === source1 ? target1 : t === source2 ? target2 : t; };
+        }
+        function makeArrayTypeMapper(sources, targets) {
+            return function (t) {
+                for (var i = 0; i < sources.length; i++) {
+                    if (t === sources[i]) {
+                        return targets ? targets[i] : anyType;
+                    }
+                }
+                return t;
+            };
+        }
+        function createTypeMapper(sources, targets) {
+            ts.Debug.assert(targets === undefined || sources.length === targets.length);
+            return sources.length === 1 ? makeUnaryTypeMapper(sources[0], targets ? targets[0] : anyType) :
+                sources.length === 2 ? makeBinaryTypeMapper(sources[0], targets ? targets[0] : anyType, sources[1], targets ? targets[1] : anyType) :
+                    makeArrayTypeMapper(sources, targets);
+        }
+        function createTypeEraser(sources) {
+            return createTypeMapper(sources, /*targets*/ undefined);
+        }
+        /**
+         * Maps forward-references to later types parameters to the empty object type.
+         * This is used during inference when instantiating type parameter defaults.
+         */
+        function createBackreferenceMapper(typeParameters, index) {
+            return function (t) { return typeParameters.indexOf(t) >= index ? emptyObjectType : t; };
+        }
+        function isInferenceContext(mapper) {
+            return !!mapper.typeParameters;
+        }
+        function cloneTypeMapper(mapper) {
+            return mapper && isInferenceContext(mapper) ?
+                createInferenceContext(mapper.typeParameters, mapper.signature, mapper.flags | 2 /* NoDefault */, mapper.compareTypes, mapper.inferences) :
+                mapper;
+        }
+        function combineTypeMappers(mapper1, mapper2) {
+            if (!mapper1)
+                return mapper2;
+            if (!mapper2)
+                return mapper1;
+            return function (t) { return instantiateType(mapper1(t), mapper2); };
+        }
+        function createReplacementMapper(source, target, baseMapper) {
+            return function (t) { return t === source ? target : baseMapper(t); };
+        }
+        function wildcardMapper(type) {
+            return type.flags & 65536 /* TypeParameter */ ? wildcardType : type;
+        }
+        function cloneTypeParameter(typeParameter) {
+            var result = createType(65536 /* TypeParameter */);
+            result.symbol = typeParameter.symbol;
+            result.target = typeParameter;
+            return result;
+        }
+        function instantiateTypePredicate(predicate, mapper) {
+            if (ts.isIdentifierTypePredicate(predicate)) {
+                return {
+                    kind: 1 /* Identifier */,
+                    parameterName: predicate.parameterName,
+                    parameterIndex: predicate.parameterIndex,
+                    type: instantiateType(predicate.type, mapper)
+                };
+            }
+            else {
+                return {
+                    kind: 0 /* This */,
+                    type: instantiateType(predicate.type, mapper)
+                };
+            }
+        }
+        function instantiateSignature(signature, mapper, eraseTypeParameters) {
+            var freshTypeParameters;
+            if (signature.typeParameters && !eraseTypeParameters) {
+                // First create a fresh set of type parameters, then include a mapping from the old to the
+                // new type parameters in the mapper function. Finally store this mapper in the new type
+                // parameters such that we can use it when instantiating constraints.
+                freshTypeParameters = ts.map(signature.typeParameters, cloneTypeParameter);
+                mapper = combineTypeMappers(createTypeMapper(signature.typeParameters, freshTypeParameters), mapper);
+                for (var _i = 0, freshTypeParameters_1 = freshTypeParameters; _i < freshTypeParameters_1.length; _i++) {
+                    var tp = freshTypeParameters_1[_i];
+                    tp.mapper = mapper;
+                }
+            }
+            // Don't compute resolvedReturnType and resolvedTypePredicate now,
+            // because using `mapper` now could trigger inferences to become fixed. (See `createInferenceContext`.)
+            // See GH#17600.
+            var result = createSignature(signature.declaration, freshTypeParameters, signature.thisParameter && instantiateSymbol(signature.thisParameter, mapper), instantiateList(signature.parameters, mapper, instantiateSymbol), 
+            /*resolvedReturnType*/ undefined, 
+            /*resolvedTypePredicate*/ undefined, signature.minArgumentCount, signature.hasRestParameter, signature.hasLiteralTypes);
+            result.target = signature;
+            result.mapper = mapper;
+            return result;
+        }
+        function instantiateSymbol(symbol, mapper) {
+            var links = getSymbolLinks(symbol);
+            if (links.type && !maybeTypeOfKind(links.type, 131072 /* Object */ | 15794176 /* Instantiable */)) {
+                // If the type of the symbol is already resolved, and if that type could not possibly
+                // be affected by instantiation, simply return the symbol itself.
+                return symbol;
+            }
+            if (ts.getCheckFlags(symbol) & 1 /* Instantiated */) {
+                // If symbol being instantiated is itself a instantiation, fetch the original target and combine the
+                // type mappers. This ensures that original type identities are properly preserved and that aliases
+                // always reference a non-aliases.
+                symbol = links.target;
+                mapper = combineTypeMappers(links.mapper, mapper);
+            }
+            // Keep the flags from the symbol we're instantiating.  Mark that is instantiated, and
+            // also transient so that we can just store data on it directly.
+            var result = createSymbol(symbol.flags, symbol.escapedName, 1 /* Instantiated */ | (ts.getCheckFlags(symbol) & 1024 /* Late */));
+            result.declarations = symbol.declarations;
+            result.parent = symbol.parent;
+            result.target = symbol;
+            result.mapper = mapper;
+            if (symbol.valueDeclaration) {
+                result.valueDeclaration = symbol.valueDeclaration;
+            }
+            if (symbol.nameType) {
+                result.nameType = symbol.nameType;
+            }
+            if (isTransientSymbol(symbol)) {
+                if (symbol.isRestParameter) {
+                    result.isRestParameter = symbol.isRestParameter;
+                }
+            }
+            return result;
+        }
+        function getAnonymousTypeInstantiation(type, mapper) {
+            var target = type.objectFlags & 64 /* Instantiated */ ? type.target : type;
+            var symbol = target.symbol;
+            var links = getSymbolLinks(symbol);
+            var typeParameters = links.outerTypeParameters;
+            if (!typeParameters) {
+                // The first time an anonymous type is instantiated we compute and store a list of the type
+                // parameters that are in scope (and therefore potentially referenced). For type literals that
+                // aren't the right hand side of a generic type alias declaration we optimize by reducing the
+                // set of type parameters to those that are possibly referenced in the literal.
+                var declaration_1 = symbol.declarations[0];
+                if (ts.isInJavaScriptFile(declaration_1)) {
+                    var paramTag = ts.findAncestor(declaration_1, ts.isJSDocParameterTag);
+                    if (paramTag) {
+                        var paramSymbol = ts.getParameterSymbolFromJSDoc(paramTag);
+                        if (paramSymbol) {
+                            declaration_1 = paramSymbol.valueDeclaration;
+                        }
+                    }
+                }
+                var outerTypeParameters = getOuterTypeParameters(declaration_1, /*includeThisTypes*/ true);
+                if (isJavaScriptConstructor(declaration_1)) {
+                    var templateTagParameters = getTypeParametersFromDeclaration(declaration_1);
+                    outerTypeParameters = ts.addRange(outerTypeParameters, templateTagParameters);
+                }
+                typeParameters = outerTypeParameters || ts.emptyArray;
+                typeParameters = symbol.flags & 2048 /* TypeLiteral */ && !target.aliasTypeArguments ?
+                    ts.filter(typeParameters, function (tp) { return isTypeParameterPossiblyReferenced(tp, declaration_1); }) :
+                    typeParameters;
+                links.outerTypeParameters = typeParameters;
+                if (typeParameters.length) {
+                    links.instantiations = ts.createMap();
+                    links.instantiations.set(getTypeListId(typeParameters), target);
+                }
+            }
+            if (typeParameters.length) {
+                // We are instantiating an anonymous type that has one or more type parameters in scope. Apply the
+                // mapper to the type parameters to produce the effective list of type arguments, and compute the
+                // instantiation cache key from the type IDs of the type arguments.
+                var combinedMapper = type.objectFlags & 64 /* Instantiated */ ? combineTypeMappers(type.mapper, mapper) : mapper;
+                var typeArguments = ts.map(typeParameters, combinedMapper);
+                var id = getTypeListId(typeArguments);
+                var result = links.instantiations.get(id);
+                if (!result) {
+                    var newMapper = createTypeMapper(typeParameters, typeArguments);
+                    result = target.objectFlags & 32 /* Mapped */ ? instantiateMappedType(target, newMapper) : instantiateAnonymousType(target, newMapper);
+                    links.instantiations.set(id, result);
+                }
+                return result;
+            }
+            return type;
+        }
+        function maybeTypeParameterReference(node) {
+            return !(node.kind === 146 /* QualifiedName */ ||
+                node.parent.kind === 162 /* TypeReference */ && node.parent.typeArguments && node === node.parent.typeName);
+        }
+        function isTypeParameterPossiblyReferenced(tp, node) {
+            // If the type parameter doesn't have exactly one declaration, if there are invening statement blocks
+            // between the node and the type parameter declaration, if the node contains actual references to the
+            // type parameter, or if the node contains type queries, we consider the type parameter possibly referenced.
+            if (tp.symbol && tp.symbol.declarations && tp.symbol.declarations.length === 1) {
+                var container_3 = tp.symbol.declarations[0].parent;
+                if (ts.findAncestor(node, function (n) { return n.kind === 213 /* Block */ ? "quit" : n === container_3; })) {
+                    return !!ts.forEachChild(node, containsReference);
+                }
+            }
+            return true;
+            function containsReference(node) {
+                switch (node.kind) {
+                    case 174 /* ThisType */:
+                        return !!tp.isThisType;
+                    case 71 /* Identifier */:
+                        return !tp.isThisType && ts.isPartOfTypeNode(node) && maybeTypeParameterReference(node) &&
+                            getTypeFromTypeNode(node) === tp;
+                    case 165 /* TypeQuery */:
+                        return true;
+                }
+                return !!ts.forEachChild(node, containsReference);
+            }
+        }
+        function instantiateMappedType(type, mapper) {
+            // Check if we have a homomorphic mapped type, i.e. a type of the form { [P in keyof T]: X } for some
+            // type variable T. If so, the mapped type is distributive over a union type and when T is instantiated
+            // to a union type A | B, we produce { [P in keyof A]: X } | { [P in keyof B]: X }. Furthermore, for
+            // homomorphic mapped types we leave primitive types alone. For example, when T is instantiated to a
+            // union type A | undefined, we produce { [P in keyof A]: X } | undefined.
+            var constraintType = getConstraintTypeFromMappedType(type);
+            if (constraintType.flags & 1048576 /* Index */) {
+                var typeVariable_1 = constraintType.type;
+                if (typeVariable_1.flags & 65536 /* TypeParameter */) {
+                    var mappedTypeVariable = instantiateType(typeVariable_1, mapper);
+                    if (typeVariable_1 !== mappedTypeVariable) {
+                        return mapType(mappedTypeVariable, function (t) {
+                            if (isMappableType(t)) {
+                                return instantiateAnonymousType(type, createReplacementMapper(typeVariable_1, t, mapper));
+                            }
+                            return t;
+                        });
+                    }
+                }
+            }
+            return instantiateAnonymousType(type, mapper);
+        }
+        function isMappableType(type) {
+            return type.flags & (3 /* AnyOrUnknown */ | 14745600 /* InstantiableNonPrimitive */ | 131072 /* Object */ | 524288 /* Intersection */);
+        }
+        function instantiateAnonymousType(type, mapper) {
+            var result = createObjectType(type.objectFlags | 64 /* Instantiated */, type.symbol);
+            if (type.objectFlags & 32 /* Mapped */) {
+                result.declaration = type.declaration;
+            }
+            result.target = type;
+            result.mapper = mapper;
+            result.aliasSymbol = type.aliasSymbol;
+            result.aliasTypeArguments = instantiateTypes(type.aliasTypeArguments, mapper);
+            return result;
+        }
+        function getConditionalTypeInstantiation(type, mapper) {
+            var root = type.root;
+            if (root.outerTypeParameters) {
+                // We are instantiating a conditional type that has one or more type parameters in scope. Apply the
+                // mapper to the type parameters to produce the effective list of type arguments, and compute the
+                // instantiation cache key from the type IDs of the type arguments.
+                var typeArguments = ts.map(root.outerTypeParameters, mapper);
+                var id = getTypeListId(typeArguments);
+                var result = root.instantiations.get(id);
+                if (!result) {
+                    var newMapper = createTypeMapper(root.outerTypeParameters, typeArguments);
+                    result = instantiateConditionalType(root, newMapper);
+                    root.instantiations.set(id, result);
+                }
+                return result;
+            }
+            return type;
+        }
+        function instantiateConditionalType(root, mapper) {
+            // Check if we have a conditional type where the check type is a naked type parameter. If so,
+            // the conditional type is distributive over union types and when T is instantiated to a union
+            // type A | B, we produce (A extends U ? X : Y) | (B extends U ? X : Y).
+            if (root.isDistributive) {
+                var checkType_1 = root.checkType;
+                var instantiatedType = mapper(checkType_1);
+                if (checkType_1 !== instantiatedType && instantiatedType.flags & (262144 /* Union */ | 32768 /* Never */)) {
+                    return mapType(instantiatedType, function (t) { return getConditionalType(root, createReplacementMapper(checkType_1, t, mapper)); });
+                }
+            }
+            return getConditionalType(root, mapper);
+        }
+        function instantiateType(type, mapper) {
+            if (type && mapper && mapper !== identityMapper) {
+                if (type.flags & 65536 /* TypeParameter */) {
+                    return mapper(type);
+                }
+                if (type.flags & 131072 /* Object */) {
+                    if (type.objectFlags & 16 /* Anonymous */) {
+                        // If the anonymous type originates in a declaration of a function, method, class, or
+                        // interface, in an object type literal, or in an object literal expression, we may need
+                        // to instantiate the type because it might reference a type parameter.
+                        return type.symbol && type.symbol.flags & (16 /* Function */ | 8192 /* Method */ | 32 /* Class */ | 2048 /* TypeLiteral */ | 4096 /* ObjectLiteral */) && type.symbol.declarations ?
+                            getAnonymousTypeInstantiation(type, mapper) : type;
+                    }
+                    if (type.objectFlags & 32 /* Mapped */) {
+                        return getAnonymousTypeInstantiation(type, mapper);
+                    }
+                    if (type.objectFlags & 4 /* Reference */) {
+                        var typeArguments = type.typeArguments;
+                        var newTypeArguments = instantiateTypes(typeArguments, mapper);
+                        return newTypeArguments !== typeArguments ? createTypeReference(type.target, newTypeArguments) : type;
+                    }
+                }
+                if (type.flags & 262144 /* Union */ && !(type.flags & 32764 /* Primitive */)) {
+                    var types = type.types;
+                    var newTypes = instantiateTypes(types, mapper);
+                    return newTypes !== types ? getUnionType(newTypes, 1 /* Literal */, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper)) : type;
+                }
+                if (type.flags & 524288 /* Intersection */) {
+                    var types = type.types;
+                    var newTypes = instantiateTypes(types, mapper);
+                    return newTypes !== types ? getIntersectionType(newTypes, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper)) : type;
+                }
+                if (type.flags & 1048576 /* Index */) {
+                    return getIndexType(instantiateType(type.type, mapper));
+                }
+                if (type.flags & 2097152 /* IndexedAccess */) {
+                    return getIndexedAccessType(instantiateType(type.objectType, mapper), instantiateType(type.indexType, mapper));
+                }
+                if (type.flags & 4194304 /* Conditional */) {
+                    return getConditionalTypeInstantiation(type, combineTypeMappers(type.mapper, mapper));
+                }
+                if (type.flags & 8388608 /* Substitution */) {
+                    return instantiateType(type.typeVariable, mapper);
+                }
+            }
+            return type;
+        }
+        function getWildcardInstantiation(type) {
+            return type.flags & (32764 /* Primitive */ | 3 /* AnyOrUnknown */ | 32768 /* Never */) ? type :
+                type.wildcardInstantiation || (type.wildcardInstantiation = instantiateType(type, wildcardMapper));
+        }
+        function instantiateIndexInfo(info, mapper) {
+            return info && createIndexInfo(instantiateType(info.type, mapper), info.isReadonly, info.declaration);
+        }
+        // Returns true if the given expression contains (at any level of nesting) a function or arrow expression
+        // that is subject to contextual typing.
+        function isContextSensitive(node) {
+            ts.Debug.assert(node.kind !== 154 /* MethodDeclaration */ || ts.isObjectLiteralMethod(node));
+            switch (node.kind) {
+                case 192 /* FunctionExpression */:
+                case 193 /* ArrowFunction */:
+                case 154 /* MethodDeclaration */:
+                    return isContextSensitiveFunctionLikeDeclaration(node);
+                case 184 /* ObjectLiteralExpression */:
+                    return ts.some(node.properties, isContextSensitive);
+                case 183 /* ArrayLiteralExpression */:
+                    return ts.some(node.elements, isContextSensitive);
+                case 201 /* ConditionalExpression */:
+                    return isContextSensitive(node.whenTrue) ||
+                        isContextSensitive(node.whenFalse);
+                case 200 /* BinaryExpression */:
+                    return node.operatorToken.kind === 54 /* BarBarToken */ &&
+                        (isContextSensitive(node.left) || isContextSensitive(node.right));
+                case 270 /* PropertyAssignment */:
+                    return isContextSensitive(node.initializer);
+                case 191 /* ParenthesizedExpression */:
+                    return isContextSensitive(node.expression);
+                case 263 /* JsxAttributes */:
+                    return ts.some(node.properties, isContextSensitive);
+                case 262 /* JsxAttribute */: {
+                    // If there is no initializer, JSX attribute has a boolean value of true which is not context sensitive.
+                    var initializer = node.initializer;
+                    return !!initializer && isContextSensitive(initializer);
+                }
+                case 265 /* JsxExpression */: {
+                    // It is possible to that node.expression is undefined (e.g <div x={} />)
+                    var expression = node.expression;
+                    return !!expression && isContextSensitive(expression);
+                }
+            }
+            return false;
+        }
+        function isContextSensitiveFunctionLikeDeclaration(node) {
+            // Functions with type parameters are not context sensitive.
+            if (node.typeParameters) {
+                return false;
+            }
+            // Functions with any parameters that lack type annotations are context sensitive.
+            if (ts.some(node.parameters, function (p) { return !ts.getEffectiveTypeAnnotationNode(p); })) {
+                return true;
+            }
+            if (node.kind !== 193 /* ArrowFunction */) {
+                // If the first parameter is not an explicit 'this' parameter, then the function has
+                // an implicit 'this' parameter which is subject to contextual typing.
+                var parameter = ts.firstOrUndefined(node.parameters);
+                if (!(parameter && ts.parameterIsThisKeyword(parameter))) {
+                    return true;
+                }
+            }
+            // TODO(anhans): A block should be context-sensitive if it has a context-sensitive return value.
+            var body = node.body;
+            return body.kind === 213 /* Block */ ? false : isContextSensitive(body);
+        }
+        function isContextSensitiveFunctionOrObjectLiteralMethod(func) {
+            return (ts.isInJavaScriptFile(func) && ts.isFunctionDeclaration(func) || isFunctionExpressionOrArrowFunction(func) || ts.isObjectLiteralMethod(func)) &&
+                isContextSensitiveFunctionLikeDeclaration(func);
+        }
+        function getTypeWithoutSignatures(type) {
+            if (type.flags & 131072 /* Object */) {
+                var resolved = resolveStructuredTypeMembers(type);
+                if (resolved.constructSignatures.length) {
+                    var result = createObjectType(16 /* Anonymous */, type.symbol);
+                    result.members = resolved.members;
+                    result.properties = resolved.properties;
+                    result.callSignatures = ts.emptyArray;
+                    result.constructSignatures = ts.emptyArray;
+                    return result;
+                }
+            }
+            else if (type.flags & 524288 /* Intersection */) {
+                return getIntersectionType(ts.map(type.types, getTypeWithoutSignatures));
+            }
+            return type;
+        }
+        // TYPE CHECKING
+        function isTypeIdenticalTo(source, target) {
+            return isTypeRelatedTo(source, target, identityRelation);
+        }
+        function compareTypesIdentical(source, target) {
+            return isTypeRelatedTo(source, target, identityRelation) ? -1 /* True */ : 0 /* False */;
+        }
+        function compareTypesAssignable(source, target) {
+            return isTypeRelatedTo(source, target, assignableRelation) ? -1 /* True */ : 0 /* False */;
+        }
+        function isTypeSubtypeOf(source, target) {
+            return isTypeRelatedTo(source, target, subtypeRelation);
+        }
+        function isTypeAssignableTo(source, target) {
+            return isTypeRelatedTo(source, target, assignableRelation);
+        }
+        // An object type S is considered to be derived from an object type T if
+        // S is a union type and every constituent of S is derived from T,
+        // T is a union type and S is derived from at least one constituent of T, or
+        // S is a type variable with a base constraint that is derived from T,
+        // T is one of the global types Object and Function and S is a subtype of T, or
+        // T occurs directly or indirectly in an 'extends' clause of S.
+        // Note that this check ignores type parameters and only considers the
+        // inheritance hierarchy.
+        function isTypeDerivedFrom(source, target) {
+            return source.flags & 262144 /* Union */ ? ts.every(source.types, function (t) { return isTypeDerivedFrom(t, target); }) :
+                target.flags & 262144 /* Union */ ? ts.some(target.types, function (t) { return isTypeDerivedFrom(source, t); }) :
+                    source.flags & 14745600 /* InstantiableNonPrimitive */ ? isTypeDerivedFrom(getBaseConstraintOfType(source) || emptyObjectType, target) :
+                        target === globalObjectType || target === globalFunctionType ? isTypeSubtypeOf(source, target) :
+                            hasBaseType(source, getTargetType(target));
+        }
+        /**
+         * This is *not* a bi-directional relationship.
+         * If one needs to check both directions for comparability, use a second call to this function or 'checkTypeComparableTo'.
+         *
+         * A type S is comparable to a type T if some (but not necessarily all) of the possible values of S are also possible values of T.
+         * It is used to check following cases:
+         *   - the types of the left and right sides of equality/inequality operators (`===`, `!==`, `==`, `!=`).
+         *   - the types of `case` clause expressions and their respective `switch` expressions.
+         *   - the type of an expression in a type assertion with the type being asserted.
+         */
+        function isTypeComparableTo(source, target) {
+            return isTypeRelatedTo(source, target, comparableRelation);
+        }
+        function areTypesComparable(type1, type2) {
+            return isTypeComparableTo(type1, type2) || isTypeComparableTo(type2, type1);
+        }
+        function checkTypeAssignableTo(source, target, errorNode, headMessage, containingMessageChain) {
+            return checkTypeRelatedTo(source, target, assignableRelation, errorNode, headMessage, containingMessageChain);
+        }
+        /**
+         * This is *not* a bi-directional relationship.
+         * If one needs to check both directions for comparability, use a second call to this function or 'isTypeComparableTo'.
+         */
+        function checkTypeComparableTo(source, target, errorNode, headMessage, containingMessageChain) {
+            return checkTypeRelatedTo(source, target, comparableRelation, errorNode, headMessage, containingMessageChain);
+        }
+        function isSignatureAssignableTo(source, target, ignoreReturnTypes) {
+            return compareSignaturesRelated(source, target, 0 /* None */, ignoreReturnTypes, /*reportErrors*/ false, 
+            /*errorReporter*/ undefined, compareTypesAssignable) !== 0 /* False */;
+        }
+        /**
+         * See signatureRelatedTo, compareSignaturesIdentical
+         */
+        function compareSignaturesRelated(source, target, callbackCheck, ignoreReturnTypes, reportErrors, errorReporter, compareTypes) {
+            // TODO (drosen): De-duplicate code between related functions.
+            if (source === target) {
+                return -1 /* True */;
+            }
+            if (!target.hasRestParameter && source.minArgumentCount > target.parameters.length) {
+                return 0 /* False */;
+            }
+            if (source.typeParameters && source.typeParameters !== target.typeParameters) {
+                target = getCanonicalSignature(target);
+                source = instantiateSignatureInContextOf(source, target, /*contextualMapper*/ undefined, compareTypes);
+            }
+            var kind = target.declaration ? target.declaration.kind : 0 /* Unknown */;
+            var strictVariance = !callbackCheck && strictFunctionTypes && kind !== 154 /* MethodDeclaration */ &&
+                kind !== 153 /* MethodSignature */ && kind !== 155 /* Constructor */;
+            var result = -1 /* True */;
+            var sourceThisType = getThisTypeOfSignature(source);
+            if (sourceThisType && sourceThisType !== voidType) {
+                var targetThisType = getThisTypeOfSignature(target);
+                if (targetThisType) {
+                    // void sources are assignable to anything.
+                    var related = !strictVariance && compareTypes(sourceThisType, targetThisType, /*reportErrors*/ false)
+                        || compareTypes(targetThisType, sourceThisType, reportErrors);
+                    if (!related) {
+                        if (reportErrors) {
+                            errorReporter(ts.Diagnostics.The_this_types_of_each_signature_are_incompatible);
+                        }
+                        return 0 /* False */;
+                    }
+                    result &= related;
+                }
+            }
+            var sourceMax = getNumNonRestParameters(source);
+            var targetMax = getNumNonRestParameters(target);
+            var checkCount = getNumParametersToCheckForSignatureRelatability(source, sourceMax, target, targetMax);
+            var sourceParams = source.parameters;
+            var targetParams = target.parameters;
+            for (var i = 0; i < checkCount; i++) {
+                var sourceType = i < sourceMax ? getTypeOfParameter(sourceParams[i]) : getRestTypeOfSignature(source);
+                var targetType = i < targetMax ? getTypeOfParameter(targetParams[i]) : getRestTypeOfSignature(target);
+                // In order to ensure that any generic type Foo<T> is at least co-variant with respect to T no matter
+                // how Foo uses T, we need to relate parameters bi-variantly (given that parameters are input positions,
+                // they naturally relate only contra-variantly). However, if the source and target parameters both have
+                // function types with a single call signature, we know we are relating two callback parameters. In
+                // that case it is sufficient to only relate the parameters of the signatures co-variantly because,
+                // similar to return values, callback parameters are output positions. This means that a Promise<T>,
+                // where T is used only in callback parameter positions, will be co-variant (as opposed to bi-variant)
+                // with respect to T.
+                var sourceSig = callbackCheck ? undefined : getSingleCallSignature(getNonNullableType(sourceType));
+                var targetSig = callbackCheck ? undefined : getSingleCallSignature(getNonNullableType(targetType));
+                var callbacks = sourceSig && targetSig && !signatureHasTypePredicate(sourceSig) && !signatureHasTypePredicate(targetSig) &&
+                    (getFalsyFlags(sourceType) & 24576 /* Nullable */) === (getFalsyFlags(targetType) & 24576 /* Nullable */);
+                var related = callbacks ?
+                    // TODO: GH#18217 It will work if they're both `undefined`, but not if only one is
+                    compareSignaturesRelated(targetSig, sourceSig, strictVariance ? 2 /* Strict */ : 1 /* Bivariant */, /*ignoreReturnTypes*/ false, reportErrors, errorReporter, compareTypes) :
+                    !callbackCheck && !strictVariance && compareTypes(sourceType, targetType, /*reportErrors*/ false) || compareTypes(targetType, sourceType, reportErrors);
+                if (!related) {
+                    if (reportErrors) {
+                        errorReporter(ts.Diagnostics.Types_of_parameters_0_and_1_are_incompatible, ts.symbolName(sourceParams[i < sourceMax ? i : sourceMax]), ts.symbolName(targetParams[i < targetMax ? i : targetMax]));
+                    }
+                    return 0 /* False */;
+                }
+                result &= related;
+            }
+            if (!ignoreReturnTypes) {
+                var targetReturnType = getReturnTypeOfSignature(target);
+                if (targetReturnType === voidType) {
+                    return result;
+                }
+                var sourceReturnType = getReturnTypeOfSignature(source);
+                // The following block preserves behavior forbidding boolean returning functions from being assignable to type guard returning functions
+                var targetTypePredicate = getTypePredicateOfSignature(target);
+                if (targetTypePredicate) {
+                    var sourceTypePredicate = getTypePredicateOfSignature(source);
+                    if (sourceTypePredicate) {
+                        result &= compareTypePredicateRelatedTo(sourceTypePredicate, targetTypePredicate, source.declaration, target.declaration, reportErrors, errorReporter, compareTypes); // TODO: GH#18217
+                    }
+                    else if (ts.isIdentifierTypePredicate(targetTypePredicate)) {
+                        if (reportErrors) {
+                            errorReporter(ts.Diagnostics.Signature_0_must_be_a_type_predicate, signatureToString(source));
+                        }
+                        return 0 /* False */;
+                    }
+                }
+                else {
+                    // When relating callback signatures, we still need to relate return types bi-variantly as otherwise
+                    // the containing type wouldn't be co-variant. For example, interface Foo<T> { add(cb: () => T): void }
+                    // wouldn't be co-variant for T without this rule.
+                    result &= callbackCheck === 1 /* Bivariant */ && compareTypes(targetReturnType, sourceReturnType, /*reportErrors*/ false) ||
+                        compareTypes(sourceReturnType, targetReturnType, reportErrors);
+                }
+            }
+            return result;
+        }
+        function compareTypePredicateRelatedTo(source, target, sourceDeclaration, targetDeclaration, reportErrors, errorReporter, compareTypes) {
+            if (source.kind !== target.kind) {
+                if (reportErrors) {
+                    errorReporter(ts.Diagnostics.A_this_based_type_guard_is_not_compatible_with_a_parameter_based_type_guard);
+                    errorReporter(ts.Diagnostics.Type_predicate_0_is_not_assignable_to_1, typePredicateToString(source), typePredicateToString(target));
+                }
+                return 0 /* False */;
+            }
+            if (source.kind === 1 /* Identifier */) {
+                var targetPredicate = target;
+                var sourceIndex = source.parameterIndex - (ts.getThisParameter(sourceDeclaration) ? 1 : 0);
+                var targetIndex = targetPredicate.parameterIndex - (ts.getThisParameter(targetDeclaration) ? 1 : 0);
+                if (sourceIndex !== targetIndex) {
+                    if (reportErrors) {
+                        errorReporter(ts.Diagnostics.Parameter_0_is_not_in_the_same_position_as_parameter_1, source.parameterName, targetPredicate.parameterName);
+                        errorReporter(ts.Diagnostics.Type_predicate_0_is_not_assignable_to_1, typePredicateToString(source), typePredicateToString(target));
+                    }
+                    return 0 /* False */;
+                }
+            }
+            var related = compareTypes(source.type, target.type, reportErrors);
+            if (related === 0 /* False */ && reportErrors) {
+                errorReporter(ts.Diagnostics.Type_predicate_0_is_not_assignable_to_1, typePredicateToString(source), typePredicateToString(target));
+            }
+            return related;
+        }
+        function isImplementationCompatibleWithOverload(implementation, overload) {
+            var erasedSource = getErasedSignature(implementation);
+            var erasedTarget = getErasedSignature(overload);
+            // First see if the return types are compatible in either direction.
+            var sourceReturnType = getReturnTypeOfSignature(erasedSource);
+            var targetReturnType = getReturnTypeOfSignature(erasedTarget);
+            if (targetReturnType === voidType
+                || isTypeRelatedTo(targetReturnType, sourceReturnType, assignableRelation)
+                || isTypeRelatedTo(sourceReturnType, targetReturnType, assignableRelation)) {
+                return isSignatureAssignableTo(erasedSource, erasedTarget, /*ignoreReturnTypes*/ true);
+            }
+            return false;
+        }
+        function getNumNonRestParameters(signature) {
+            var numParams = signature.parameters.length;
+            return signature.hasRestParameter ?
+                numParams - 1 :
+                numParams;
+        }
+        function getNumParametersToCheckForSignatureRelatability(source, sourceNonRestParamCount, target, targetNonRestParamCount) {
+            if (source.hasRestParameter === target.hasRestParameter) {
+                if (source.hasRestParameter) {
+                    // If both have rest parameters, get the max and add 1 to
+                    // compensate for the rest parameter.
+                    return Math.max(sourceNonRestParamCount, targetNonRestParamCount) + 1;
+                }
+                else {
+                    return Math.min(sourceNonRestParamCount, targetNonRestParamCount);
+                }
+            }
+            else {
+                // Return the count for whichever signature doesn't have rest parameters.
+                return source.hasRestParameter ?
+                    targetNonRestParamCount :
+                    sourceNonRestParamCount;
+            }
+        }
+        function isEmptyResolvedType(t) {
+            return t.properties.length === 0 &&
+                t.callSignatures.length === 0 &&
+                t.constructSignatures.length === 0 &&
+                !t.stringIndexInfo &&
+                !t.numberIndexInfo;
+        }
+        function isEmptyObjectType(type) {
+            return type.flags & 131072 /* Object */ ? isEmptyResolvedType(resolveStructuredTypeMembers(type)) :
+                type.flags & 16777216 /* NonPrimitive */ ? true :
+                    type.flags & 262144 /* Union */ ? ts.some(type.types, isEmptyObjectType) :
+                        type.flags & 524288 /* Intersection */ ? ts.every(type.types, isEmptyObjectType) :
+                            false;
+        }
+        function isEnumTypeRelatedTo(sourceSymbol, targetSymbol, errorReporter) {
+            if (sourceSymbol === targetSymbol) {
+                return true;
+            }
+            var id = getSymbolId(sourceSymbol) + "," + getSymbolId(targetSymbol);
+            var relation = enumRelation.get(id);
+            if (relation !== undefined) {
+                return relation;
+            }
+            if (sourceSymbol.escapedName !== targetSymbol.escapedName || !(sourceSymbol.flags & 256 /* RegularEnum */) || !(targetSymbol.flags & 256 /* RegularEnum */)) {
+                enumRelation.set(id, false);
+                return false;
+            }
+            var targetEnumType = getTypeOfSymbol(targetSymbol);
+            for (var _i = 0, _a = getPropertiesOfType(getTypeOfSymbol(sourceSymbol)); _i < _a.length; _i++) {
+                var property = _a[_i];
+                if (property.flags & 8 /* EnumMember */) {
+                    var targetProperty = getPropertyOfType(targetEnumType, property.escapedName);
+                    if (!targetProperty || !(targetProperty.flags & 8 /* EnumMember */)) {
+                        if (errorReporter) {
+                            errorReporter(ts.Diagnostics.Property_0_is_missing_in_type_1, ts.symbolName(property), typeToString(getDeclaredTypeOfSymbol(targetSymbol), /*enclosingDeclaration*/ undefined, 64 /* UseFullyQualifiedType */));
+                        }
+                        enumRelation.set(id, false);
+                        return false;
+                    }
+                }
+            }
+            enumRelation.set(id, true);
+            return true;
+        }
+        function isSimpleTypeRelatedTo(source, target, relation, errorReporter) {
+            var s = source.flags;
+            var t = target.flags;
+            if (t & 3 /* AnyOrUnknown */ || s & 32768 /* Never */ || source === wildcardType)
+                return true;
+            if (t & 32768 /* Never */)
+                return false;
+            if (s & 68 /* StringLike */ && t & 4 /* String */)
+                return true;
+            if (s & 64 /* StringLiteral */ && s & 512 /* EnumLiteral */ &&
+                t & 64 /* StringLiteral */ && !(t & 512 /* EnumLiteral */) &&
+                source.value === target.value)
+                return true;
+            if (s & 168 /* NumberLike */ && t & 8 /* Number */)
+                return true;
+            if (s & 128 /* NumberLiteral */ && s & 512 /* EnumLiteral */ &&
+                t & 128 /* NumberLiteral */ && !(t & 512 /* EnumLiteral */) &&
+                source.value === target.value)
+                return true;
+            if (s & 272 /* BooleanLike */ && t & 16 /* Boolean */)
+                return true;
+            if (s & 3072 /* ESSymbolLike */ && t & 1024 /* ESSymbol */)
+                return true;
+            if (s & 32 /* Enum */ && t & 32 /* Enum */ && isEnumTypeRelatedTo(source.symbol, target.symbol, errorReporter))
+                return true;
+            if (s & 512 /* EnumLiteral */ && t & 512 /* EnumLiteral */) {
+                if (s & 262144 /* Union */ && t & 262144 /* Union */ && isEnumTypeRelatedTo(source.symbol, target.symbol, errorReporter))
+                    return true;
+                if (s & 448 /* Literal */ && t & 448 /* Literal */ &&
+                    source.value === target.value &&
+                    isEnumTypeRelatedTo(getParentOfSymbol(source.symbol), getParentOfSymbol(target.symbol), errorReporter))
+                    return true;
+            }
+            if (s & 8192 /* Undefined */ && (!strictNullChecks || t & (8192 /* Undefined */ | 4096 /* Void */)))
+                return true;
+            if (s & 16384 /* Null */ && (!strictNullChecks || t & 16384 /* Null */))
+                return true;
+            if (s & 131072 /* Object */ && t & 16777216 /* NonPrimitive */)
+                return true;
+            if (s & 2048 /* UniqueESSymbol */ || t & 2048 /* UniqueESSymbol */)
+                return false;
+            if (relation === assignableRelation || relation === definitelyAssignableRelation || relation === comparableRelation) {
+                if (s & 1 /* Any */)
+                    return true;
+                // Type number or any numeric literal type is assignable to any numeric enum type or any
+                // numeric enum literal type. This rule exists for backwards compatibility reasons because
+                // bit-flag enum types sometimes look like literal enum types with numeric literal values.
+                if (s & (8 /* Number */ | 128 /* NumberLiteral */) && !(s & 512 /* EnumLiteral */) && (t & 32 /* Enum */ || t & 128 /* NumberLiteral */ && t & 512 /* EnumLiteral */))
+                    return true;
+            }
+            return false;
+        }
+        function isTypeRelatedTo(source, target, relation) {
+            if (source.flags & 192 /* StringOrNumberLiteral */ && source.flags & 33554432 /* FreshLiteral */) {
+                source = source.regularType;
+            }
+            if (target.flags & 192 /* StringOrNumberLiteral */ && target.flags & 33554432 /* FreshLiteral */) {
+                target = target.regularType;
+            }
+            if (source === target ||
+                relation === comparableRelation && !(target.flags & 32768 /* Never */) && isSimpleTypeRelatedTo(target, source, relation) ||
+                relation !== identityRelation && isSimpleTypeRelatedTo(source, target, relation)) {
+                return true;
+            }
+            if (source.flags & 131072 /* Object */ && target.flags & 131072 /* Object */) {
+                var related = relation.get(getRelationKey(source, target, relation));
+                if (related !== undefined) {
+                    return related === 1 /* Succeeded */;
+                }
+            }
+            if (source.flags & 16711680 /* StructuredOrInstantiable */ || target.flags & 16711680 /* StructuredOrInstantiable */) {
+                return checkTypeRelatedTo(source, target, relation, /*errorNode*/ undefined);
+            }
+            return false;
+        }
+        function isIgnoredJsxProperty(source, sourceProp, targetMemberType) {
+            return ts.getObjectFlags(source) & 4096 /* JsxAttributes */ && !(isUnhyphenatedJsxName(sourceProp.escapedName) || targetMemberType);
+        }
+        /**
+         * Checks if 'source' is related to 'target' (e.g.: is a assignable to).
+         * @param source The left-hand-side of the relation.
+         * @param target The right-hand-side of the relation.
+         * @param relation The relation considered. One of 'identityRelation', 'subtypeRelation', 'assignableRelation', or 'comparableRelation'.
+         * Used as both to determine which checks are performed and as a cache of previously computed results.
+         * @param errorNode The suggested node upon which all errors will be reported, if defined. This may or may not be the actual node used.
+         * @param headMessage If the error chain should be prepended by a head message, then headMessage will be used.
+         * @param containingMessageChain A chain of errors to prepend any new errors found.
+         */
+        function checkTypeRelatedTo(source, target, relation, errorNode, headMessage, containingMessageChain) {
+            var errorInfo;
+            var maybeKeys;
+            var sourceStack;
+            var targetStack;
+            var maybeCount = 0;
+            var depth = 0;
+            var expandingFlags = 0 /* None */;
+            var overflow = false;
+            var isIntersectionConstituent = false;
+            ts.Debug.assert(relation !== identityRelation || !errorNode, "no error reporting in identity checking");
+            var result = isRelatedTo(source, target, /*reportErrors*/ !!errorNode, headMessage);
+            if (overflow) {
+                error(errorNode, ts.Diagnostics.Excessive_stack_depth_comparing_types_0_and_1, typeToString(source), typeToString(target));
+            }
+            else if (errorInfo) {
+                if (containingMessageChain) {
+                    var chain_1 = containingMessageChain();
+                    if (chain_1) {
+                        errorInfo = ts.concatenateDiagnosticMessageChains(chain_1, errorInfo);
+                    }
+                }
+                diagnostics.add(ts.createDiagnosticForNodeFromMessageChain(errorNode, errorInfo)); // TODO: GH#18217
+            }
+            // Check if we should issue an extra diagnostic to produce a quickfix for a slightly incorrect import statement
+            if (headMessage && errorNode && !result && source.symbol) {
+                var links = getSymbolLinks(source.symbol);
+                if (links.originatingImport && !ts.isImportCall(links.originatingImport)) {
+                    var helpfulRetry = checkTypeRelatedTo(getTypeOfSymbol(links.target), target, relation, /*errorNode*/ undefined);
+                    if (helpfulRetry) {
+                        // Likely an incorrect import. Issue a helpful diagnostic to produce a quickfix to change the import
+                        diagnostics.add(ts.createDiagnosticForNode(links.originatingImport, ts.Diagnostics.A_namespace_style_import_cannot_be_called_or_constructed_and_will_cause_a_failure_at_runtime));
+                    }
+                }
+            }
+            return result !== 0 /* False */;
+            function reportError(message, arg0, arg1, arg2) {
+                ts.Debug.assert(!!errorNode);
+                errorInfo = ts.chainDiagnosticMessages(errorInfo, message, arg0, arg1, arg2);
+            }
+            function reportRelationError(message, source, target) {
+                var sourceType = typeToString(source);
+                var targetType = typeToString(target);
+                if (sourceType === targetType) {
+                    sourceType = typeToString(source, /*enclosingDeclaration*/ undefined, 64 /* UseFullyQualifiedType */);
+                    targetType = typeToString(target, /*enclosingDeclaration*/ undefined, 64 /* UseFullyQualifiedType */);
+                }
+                if (!message) {
+                    if (relation === comparableRelation) {
+                        message = ts.Diagnostics.Type_0_is_not_comparable_to_type_1;
+                    }
+                    else if (sourceType === targetType) {
+                        message = ts.Diagnostics.Type_0_is_not_assignable_to_type_1_Two_different_types_with_this_name_exist_but_they_are_unrelated;
+                    }
+                    else {
+                        message = ts.Diagnostics.Type_0_is_not_assignable_to_type_1;
+                    }
+                }
+                reportError(message, sourceType, targetType);
+            }
+            function tryElaborateErrorsForPrimitivesAndObjects(source, target) {
+                var sourceType = typeToString(source);
+                var targetType = typeToString(target);
+                if ((globalStringType === source && stringType === target) ||
+                    (globalNumberType === source && numberType === target) ||
+                    (globalBooleanType === source && booleanType === target) ||
+                    (getGlobalESSymbolType(/*reportErrors*/ false) === source && esSymbolType === target)) {
+                    reportError(ts.Diagnostics._0_is_a_primitive_but_1_is_a_wrapper_object_Prefer_using_0_when_possible, targetType, sourceType);
+                }
+            }
+            function isUnionOrIntersectionTypeWithoutNullableConstituents(type) {
+                if (!(type.flags & 786432 /* UnionOrIntersection */)) {
+                    return false;
+                }
+                // at this point we know that this is union or intersection type possibly with nullable constituents.
+                // check if we still will have compound type if we ignore nullable components.
+                var seenNonNullable = false;
+                for (var _i = 0, _a = type.types; _i < _a.length; _i++) {
+                    var t = _a[_i];
+                    if (t.flags & 24576 /* Nullable */) {
+                        continue;
+                    }
+                    if (seenNonNullable) {
+                        return true;
+                    }
+                    seenNonNullable = true;
+                }
+                return false;
+            }
+            /**
+             * Compare two types and return
+             * * Ternary.True if they are related with no assumptions,
+             * * Ternary.Maybe if they are related with assumptions of other relationships, or
+             * * Ternary.False if they are not related.
+             */
+            function isRelatedTo(source, target, reportErrors, headMessage) {
+                if (reportErrors === void 0) { reportErrors = false; }
+                if (source.flags & 192 /* StringOrNumberLiteral */ && source.flags & 33554432 /* FreshLiteral */) {
+                    source = source.regularType;
+                }
+                if (target.flags & 192 /* StringOrNumberLiteral */ && target.flags & 33554432 /* FreshLiteral */) {
+                    target = target.regularType;
+                }
+                if (source.flags & 8388608 /* Substitution */) {
+                    source = relation === definitelyAssignableRelation ? source.typeVariable : source.substitute;
+                }
+                if (target.flags & 8388608 /* Substitution */) {
+                    target = target.typeVariable;
+                }
+                if (source.flags & 2097152 /* IndexedAccess */) {
+                    source = getSimplifiedType(source);
+                }
+                if (target.flags & 2097152 /* IndexedAccess */) {
+                    target = getSimplifiedType(target);
+                }
+                // both types are the same - covers 'they are the same primitive type or both are Any' or the same type parameter cases
+                if (source === target)
+                    return -1 /* True */;
+                if (relation === identityRelation) {
+                    return isIdenticalTo(source, target);
+                }
+                if (relation === comparableRelation && !(target.flags & 32768 /* Never */) && isSimpleTypeRelatedTo(target, source, relation) ||
+                    isSimpleTypeRelatedTo(source, target, relation, reportErrors ? reportError : undefined))
+                    return -1 /* True */;
+                if (isObjectLiteralType(source) && source.flags & 33554432 /* FreshLiteral */) {
+                    var discriminantType = target.flags & 262144 /* Union */ ? findMatchingDiscriminantType(source, target) : undefined;
+                    if (hasExcessProperties(source, target, discriminantType, reportErrors)) {
+                        if (reportErrors) {
+                            reportRelationError(headMessage, source, target);
+                        }
+                        return 0 /* False */;
+                    }
+                    // Above we check for excess properties with respect to the entire target type. When union
+                    // and intersection types are further deconstructed on the target side, we don't want to
+                    // make the check again (as it might fail for a partial target type). Therefore we obtain
+                    // the regular source type and proceed with that.
+                    if (isUnionOrIntersectionTypeWithoutNullableConstituents(target) && !discriminantType) {
+                        source = getRegularTypeOfObjectLiteral(source);
+                    }
+                }
+                if (relation !== comparableRelation &&
+                    !(source.flags & 786432 /* UnionOrIntersection */) &&
+                    !(target.flags & 262144 /* Union */) &&
+                    !isIntersectionConstituent &&
+                    source !== globalObjectType &&
+                    (getPropertiesOfType(source).length > 0 || typeHasCallOrConstructSignatures(source)) &&
+                    isWeakType(target) &&
+                    !hasCommonProperties(source, target)) {
+                    if (reportErrors) {
+                        var calls = getSignaturesOfType(source, 0 /* Call */);
+                        var constructs = getSignaturesOfType(source, 1 /* Construct */);
+                        if (calls.length > 0 && isRelatedTo(getReturnTypeOfSignature(calls[0]), target, /*reportErrors*/ false) ||
+                            constructs.length > 0 && isRelatedTo(getReturnTypeOfSignature(constructs[0]), target, /*reportErrors*/ false)) {
+                            reportError(ts.Diagnostics.Value_of_type_0_has_no_properties_in_common_with_type_1_Did_you_mean_to_call_it, typeToString(source), typeToString(target));
+                        }
+                        else {
+                            reportError(ts.Diagnostics.Type_0_has_no_properties_in_common_with_type_1, typeToString(source), typeToString(target));
+                        }
+                    }
+                    return 0 /* False */;
+                }
+                var result = 0 /* False */;
+                var saveErrorInfo = errorInfo;
+                var saveIsIntersectionConstituent = isIntersectionConstituent;
+                isIntersectionConstituent = false;
+                // Note that these checks are specifically ordered to produce correct results. In particular,
+                // we need to deconstruct unions before intersections (because unions are always at the top),
+                // and we need to handle "each" relations before "some" relations for the same kind of type.
+                if (source.flags & 262144 /* Union */) {
+                    result = relation === comparableRelation ?
+                        someTypeRelatedToType(source, target, reportErrors && !(source.flags & 32764 /* Primitive */)) :
+                        eachTypeRelatedToType(source, target, reportErrors && !(source.flags & 32764 /* Primitive */));
+                }
+                else {
+                    if (target.flags & 262144 /* Union */) {
+                        result = typeRelatedToSomeType(source, target, reportErrors && !(source.flags & 32764 /* Primitive */) && !(target.flags & 32764 /* Primitive */));
+                    }
+                    else if (target.flags & 524288 /* Intersection */) {
+                        isIntersectionConstituent = true;
+                        result = typeRelatedToEachType(source, target, reportErrors);
+                    }
+                    else if (source.flags & 524288 /* Intersection */) {
+                        // Check to see if any constituents of the intersection are immediately related to the target.
+                        //
+                        // Don't report errors though. Checking whether a constituent is related to the source is not actually
+                        // useful and leads to some confusing error messages. Instead it is better to let the below checks
+                        // take care of this, or to not elaborate at all. For instance,
+                        //
+                        //    - For an object type (such as 'C = A & B'), users are usually more interested in structural errors.
+                        //
+                        //    - For a union type (such as '(A | B) = (C & D)'), it's better to hold onto the whole intersection
+                        //          than to report that 'D' is not assignable to 'A' or 'B'.
+                        //
+                        //    - For a primitive type or type parameter (such as 'number = A & B') there is no point in
+                        //          breaking the intersection apart.
+                        result = someTypeRelatedToType(source, target, /*reportErrors*/ false);
+                    }
+                    if (!result && (source.flags & 16711680 /* StructuredOrInstantiable */ || target.flags & 16711680 /* StructuredOrInstantiable */)) {
+                        if (result = recursiveTypeRelatedTo(source, target, reportErrors)) {
+                            errorInfo = saveErrorInfo;
+                        }
+                    }
+                }
+                if (!result && source.flags & 524288 /* Intersection */) {
+                    // The combined constraint of an intersection type is the intersection of the constraints of
+                    // the constituents. When an intersection type contains instantiable types with union type
+                    // constraints, there are situations where we need to examine the combined constraint. One is
+                    // when the target is a union type. Another is when the intersection contains types belonging
+                    // to one of the disjoint domains. For example, given type variables T and U, each with the
+                    // constraint 'string | number', the combined constraint of 'T & U' is 'string | number' and
+                    // we need to check this constraint against a union on the target side. Also, given a type
+                    // variable V constrained to 'string | number', 'V & number' has a combined constraint of
+                    // 'string & number | number & number' which reduces to just 'number'.
+                    var constraint = getUnionConstraintOfIntersection(source, !!(target.flags & 262144 /* Union */));
+                    if (constraint) {
+                        if (result = isRelatedTo(constraint, target, reportErrors)) {
+                            errorInfo = saveErrorInfo;
+                        }
+                    }
+                }
+                isIntersectionConstituent = saveIsIntersectionConstituent;
+                if (!result && reportErrors) {
+                    if (source.flags & 131072 /* Object */ && target.flags & 32764 /* Primitive */) {
+                        tryElaborateErrorsForPrimitivesAndObjects(source, target);
+                    }
+                    else if (source.symbol && source.flags & 131072 /* Object */ && globalObjectType === source) {
+                        reportError(ts.Diagnostics.The_Object_type_is_assignable_to_very_few_other_types_Did_you_mean_to_use_the_any_type_instead);
+                    }
+                    else if (ts.getObjectFlags(source) & 4096 /* JsxAttributes */ && target.flags & 524288 /* Intersection */) {
+                        var targetTypes = target.types;
+                        var intrinsicAttributes = getJsxType(JsxNames.IntrinsicAttributes, errorNode);
+                        var intrinsicClassAttributes = getJsxType(JsxNames.IntrinsicClassAttributes, errorNode);
+                        if (intrinsicAttributes !== errorType && intrinsicClassAttributes !== errorType &&
+                            (ts.contains(targetTypes, intrinsicAttributes) || ts.contains(targetTypes, intrinsicClassAttributes))) {
+                            // do not report top error
+                            return result;
+                        }
+                    }
+                    reportRelationError(headMessage, source, target);
+                }
+                return result;
+            }
+            function isIdenticalTo(source, target) {
+                var result;
+                var flags = source.flags & target.flags;
+                if (flags & 131072 /* Object */) {
+                    return recursiveTypeRelatedTo(source, target, /*reportErrors*/ false);
+                }
+                if (flags & (262144 /* Union */ | 524288 /* Intersection */)) {
+                    if (result = eachTypeRelatedToSomeType(source, target)) {
+                        if (result &= eachTypeRelatedToSomeType(target, source)) {
+                            return result;
+                        }
+                    }
+                }
+                if (flags & 1048576 /* Index */) {
+                    return isRelatedTo(source.type, target.type, /*reportErrors*/ false);
+                }
+                if (flags & 2097152 /* IndexedAccess */) {
+                    if (result = isRelatedTo(source.objectType, target.objectType, /*reportErrors*/ false)) {
+                        if (result &= isRelatedTo(source.indexType, target.indexType, /*reportErrors*/ false)) {
+                            return result;
+                        }
+                    }
+                }
+                if (flags & 4194304 /* Conditional */) {
+                    if (source.root.isDistributive === target.root.isDistributive) {
+                        if (result = isRelatedTo(source.checkType, target.checkType, /*reportErrors*/ false)) {
+                            if (result &= isRelatedTo(source.extendsType, target.extendsType, /*reportErrors*/ false)) {
+                                if (result &= isRelatedTo(getTrueTypeFromConditionalType(source), getTrueTypeFromConditionalType(target), /*reportErrors*/ false)) {
+                                    if (result &= isRelatedTo(getFalseTypeFromConditionalType(source), getFalseTypeFromConditionalType(target), /*reportErrors*/ false)) {
+                                        return result;
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+                if (flags & 8388608 /* Substitution */) {
+                    return isRelatedTo(source.substitute, target.substitute, /*reportErrors*/ false);
+                }
+                return 0 /* False */;
+            }
+            function hasExcessProperties(source, target, discriminant, reportErrors) {
+                if (maybeTypeOfKind(target, 131072 /* Object */) && !(ts.getObjectFlags(target) & 512 /* ObjectLiteralPatternWithComputedProperties */)) {
+                    var isComparingJsxAttributes = !!(ts.getObjectFlags(source) & 4096 /* JsxAttributes */);
+                    if ((relation === assignableRelation || relation === definitelyAssignableRelation || relation === comparableRelation) &&
+                        (isTypeSubsetOf(globalObjectType, target) || (!isComparingJsxAttributes && isEmptyObjectType(target)))) {
+                        return false;
+                    }
+                    if (discriminant) {
+                        // check excess properties against discriminant type only, not the entire union
+                        return hasExcessProperties(source, discriminant, /*discriminant*/ undefined, reportErrors);
+                    }
+                    var _loop_7 = function (prop) {
+                        if (!isKnownProperty(target, prop.escapedName, isComparingJsxAttributes)) {
+                            if (reportErrors) {
+                                // We know *exactly* where things went wrong when comparing the types.
+                                // Use this property as the error node as this will be more helpful in
+                                // reasoning about what went wrong.
+                                if (!errorNode)
+                                    return { value: ts.Debug.fail() };
+                                if (ts.isJsxAttributes(errorNode) || ts.isJsxOpeningLikeElement(errorNode)) {
+                                    // JsxAttributes has an object-literal flag and undergo same type-assignablity check as normal object-literal.
+                                    // However, using an object-literal error message will be very confusing to the users so we give different a message.
+                                    reportError(ts.Diagnostics.Property_0_does_not_exist_on_type_1, symbolToString(prop), typeToString(target));
+                                }
+                                else {
+                                    // use the property's value declaration if the property is assigned inside the literal itself
+                                    var objectLiteralDeclaration_1 = source.symbol && ts.firstOrUndefined(source.symbol.declarations);
+                                    var suggestion = void 0;
+                                    if (prop.valueDeclaration && ts.findAncestor(prop.valueDeclaration, function (d) { return d === objectLiteralDeclaration_1; })) {
+                                        var propDeclaration = prop.valueDeclaration;
+                                        ts.Debug.assertNode(propDeclaration, ts.isObjectLiteralElementLike);
+                                        errorNode = propDeclaration;
+                                        var name = propDeclaration.name;
+                                        if (ts.isIdentifier(name)) {
+                                            suggestion = getSuggestionForNonexistentProperty(name, target);
+                                        }
+                                    }
+                                    if (suggestion !== undefined) {
+                                        reportError(ts.Diagnostics.Object_literal_may_only_specify_known_properties_but_0_does_not_exist_in_type_1_Did_you_mean_to_write_2, symbolToString(prop), typeToString(target), suggestion);
+                                    }
+                                    else {
+                                        reportError(ts.Diagnostics.Object_literal_may_only_specify_known_properties_and_0_does_not_exist_in_type_1, symbolToString(prop), typeToString(target));
+                                    }
+                                }
+                            }
+                            return { value: true };
+                        }
+                    };
+                    for (var _i = 0, _a = getPropertiesOfObjectType(source); _i < _a.length; _i++) {
+                        var prop = _a[_i];
+                        var state_3 = _loop_7(prop);
+                        if (typeof state_3 === "object")
+                            return state_3.value;
+                    }
+                }
+                return false;
+            }
+            function eachTypeRelatedToSomeType(source, target) {
+                var result = -1 /* True */;
+                var sourceTypes = source.types;
+                for (var _i = 0, sourceTypes_1 = sourceTypes; _i < sourceTypes_1.length; _i++) {
+                    var sourceType = sourceTypes_1[_i];
+                    var related = typeRelatedToSomeType(sourceType, target, /*reportErrors*/ false);
+                    if (!related) {
+                        return 0 /* False */;
+                    }
+                    result &= related;
+                }
+                return result;
+            }
+            function typeRelatedToSomeType(source, target, reportErrors) {
+                var targetTypes = target.types;
+                if (target.flags & 262144 /* Union */ && containsType(targetTypes, source)) {
+                    return -1 /* True */;
+                }
+                for (var _i = 0, targetTypes_1 = targetTypes; _i < targetTypes_1.length; _i++) {
+                    var type = targetTypes_1[_i];
+                    var related = isRelatedTo(source, type, /*reportErrors*/ false);
+                    if (related) {
+                        return related;
+                    }
+                }
+                if (reportErrors) {
+                    var discriminantType = findMatchingDiscriminantType(source, target);
+                    isRelatedTo(source, discriminantType || targetTypes[targetTypes.length - 1], /*reportErrors*/ true);
+                }
+                return 0 /* False */;
+            }
+            // Keep this up-to-date with the same logic within `getApparentTypeOfContextualType`, since they should behave similarly
+            function findMatchingDiscriminantType(source, target) {
+                var match;
+                var sourceProperties = getPropertiesOfObjectType(source);
+                if (sourceProperties) {
+                    var sourcePropertiesFiltered = findDiscriminantProperties(sourceProperties, target);
+                    if (sourcePropertiesFiltered) {
+                        for (var _i = 0, sourcePropertiesFiltered_1 = sourcePropertiesFiltered; _i < sourcePropertiesFiltered_1.length; _i++) {
+                            var sourceProperty = sourcePropertiesFiltered_1[_i];
+                            var sourceType = getTypeOfSymbol(sourceProperty);
+                            for (var _a = 0, _b = target.types; _a < _b.length; _a++) {
+                                var type = _b[_a];
+                                var targetType = getTypeOfPropertyOfType(type, sourceProperty.escapedName);
+                                if (targetType && isRelatedTo(sourceType, targetType)) {
+                                    if (type === match)
+                                        continue; // Finding multiple fields which discriminate to the same type is fine
+                                    if (match) {
+                                        return undefined;
+                                    }
+                                    match = type;
+                                }
+                            }
+                        }
+                    }
+                }
+                return match;
+            }
+            function typeRelatedToEachType(source, target, reportErrors) {
+                var result = -1 /* True */;
+                var targetTypes = target.types;
+                for (var _i = 0, targetTypes_2 = targetTypes; _i < targetTypes_2.length; _i++) {
+                    var targetType = targetTypes_2[_i];
+                    var related = isRelatedTo(source, targetType, reportErrors);
+                    if (!related) {
+                        return 0 /* False */;
+                    }
+                    result &= related;
+                }
+                return result;
+            }
+            function someTypeRelatedToType(source, target, reportErrors) {
+                var sourceTypes = source.types;
+                if (source.flags & 262144 /* Union */ && containsType(sourceTypes, target)) {
+                    return -1 /* True */;
+                }
+                var len = sourceTypes.length;
+                for (var i = 0; i < len; i++) {
+                    var related = isRelatedTo(sourceTypes[i], target, reportErrors && i === len - 1);
+                    if (related) {
+                        return related;
+                    }
+                }
+                return 0 /* False */;
+            }
+            function eachTypeRelatedToType(source, target, reportErrors) {
+                var result = -1 /* True */;
+                var sourceTypes = source.types;
+                for (var _i = 0, sourceTypes_2 = sourceTypes; _i < sourceTypes_2.length; _i++) {
+                    var sourceType = sourceTypes_2[_i];
+                    var related = isRelatedTo(sourceType, target, reportErrors);
+                    if (!related) {
+                        return 0 /* False */;
+                    }
+                    result &= related;
+                }
+                return result;
+            }
+            function typeArgumentsRelatedTo(source, target, variances, reportErrors) {
+                var sources = source.typeArguments || ts.emptyArray;
+                var targets = target.typeArguments || ts.emptyArray;
+                if (sources.length !== targets.length && relation === identityRelation) {
+                    return 0 /* False */;
+                }
+                var length = sources.length <= targets.length ? sources.length : targets.length;
+                var result = -1 /* True */;
+                for (var i = 0; i < length; i++) {
+                    // When variance information isn't available we default to covariance. This happens
+                    // in the process of computing variance information for recursive types and when
+                    // comparing 'this' type arguments.
+                    var variance = i < variances.length ? variances[i] : 1 /* Covariant */;
+                    // We ignore arguments for independent type parameters (because they're never witnessed).
+                    if (variance !== 4 /* Independent */) {
+                        var s = sources[i];
+                        var t = targets[i];
+                        var related = -1 /* True */;
+                        if (variance === 1 /* Covariant */) {
+                            related = isRelatedTo(s, t, reportErrors);
+                        }
+                        else if (variance === 2 /* Contravariant */) {
+                            related = isRelatedTo(t, s, reportErrors);
+                        }
+                        else if (variance === 3 /* Bivariant */) {
+                            // In the bivariant case we first compare contravariantly without reporting
+                            // errors. Then, if that doesn't succeed, we compare covariantly with error
+                            // reporting. Thus, error elaboration will be based on the the covariant check,
+                            // which is generally easier to reason about.
+                            related = isRelatedTo(t, s, /*reportErrors*/ false);
+                            if (!related) {
+                                related = isRelatedTo(s, t, reportErrors);
+                            }
+                        }
+                        else {
+                            // In the invariant case we first compare covariantly, and only when that
+                            // succeeds do we proceed to compare contravariantly. Thus, error elaboration
+                            // will typically be based on the covariant check.
+                            related = isRelatedTo(s, t, reportErrors);
+                            if (related) {
+                                related &= isRelatedTo(t, s, reportErrors);
+                            }
+                        }
+                        if (!related) {
+                            return 0 /* False */;
+                        }
+                        result &= related;
+                    }
+                }
+                return result;
+            }
+            // Determine if possibly recursive types are related. First, check if the result is already available in the global cache.
+            // Second, check if we have already started a comparison of the given two types in which case we assume the result to be true.
+            // Third, check if both types are part of deeply nested chains of generic type instantiations and if so assume the types are
+            // equal and infinitely expanding. Fourth, if we have reached a depth of 100 nested comparisons, assume we have runaway recursion
+            // and issue an error. Otherwise, actually compare the structure of the two types.
+            function recursiveTypeRelatedTo(source, target, reportErrors) {
+                if (overflow) {
+                    return 0 /* False */;
+                }
+                var id = getRelationKey(source, target, relation);
+                var related = relation.get(id);
+                if (related !== undefined) {
+                    if (reportErrors && related === 2 /* Failed */) {
+                        // We are elaborating errors and the cached result is an unreported failure. Record the result as a reported
+                        // failure and continue computing the relation such that errors get reported.
+                        relation.set(id, 3 /* FailedAndReported */);
+                    }
+                    else {
+                        return related === 1 /* Succeeded */ ? -1 /* True */ : 0 /* False */;
+                    }
+                }
+                if (!maybeKeys) {
+                    maybeKeys = [];
+                    sourceStack = [];
+                    targetStack = [];
+                }
+                else {
+                    for (var i = 0; i < maybeCount; i++) {
+                        // If source and target are already being compared, consider them related with assumptions
+                        if (id === maybeKeys[i]) {
+                            return 1 /* Maybe */;
+                        }
+                    }
+                    if (depth === 100) {
+                        overflow = true;
+                        return 0 /* False */;
+                    }
+                }
+                var maybeStart = maybeCount;
+                maybeKeys[maybeCount] = id;
+                maybeCount++;
+                sourceStack[depth] = source;
+                targetStack[depth] = target;
+                depth++;
+                var saveExpandingFlags = expandingFlags;
+                if (!(expandingFlags & 1 /* Source */) && isDeeplyNestedType(source, sourceStack, depth))
+                    expandingFlags |= 1 /* Source */;
+                if (!(expandingFlags & 2 /* Target */) && isDeeplyNestedType(target, targetStack, depth))
+                    expandingFlags |= 2 /* Target */;
+                var result = expandingFlags !== 3 /* Both */ ? structuredTypeRelatedTo(source, target, reportErrors) : 1 /* Maybe */;
+                expandingFlags = saveExpandingFlags;
+                depth--;
+                if (result) {
+                    if (result === -1 /* True */ || depth === 0) {
+                        // If result is definitely true, record all maybe keys as having succeeded
+                        for (var i = maybeStart; i < maybeCount; i++) {
+                            relation.set(maybeKeys[i], 1 /* Succeeded */);
+                        }
+                        maybeCount = maybeStart;
+                    }
+                }
+                else {
+                    // A false result goes straight into global cache (when something is false under
+                    // assumptions it will also be false without assumptions)
+                    relation.set(id, reportErrors ? 3 /* FailedAndReported */ : 2 /* Failed */);
+                    maybeCount = maybeStart;
+                }
+                return result;
+            }
+            function getConstraintForRelation(type) {
+                return relation === definitelyAssignableRelation ? undefined : getConstraintOfType(type);
+            }
+            function structuredTypeRelatedTo(source, target, reportErrors) {
+                var result;
+                var originalErrorInfo;
+                var saveErrorInfo = errorInfo;
+                if (target.flags & 65536 /* TypeParameter */) {
+                    // A source type { [P in keyof T]: X } is related to a target type T if X is related to T[P].
+                    if (ts.getObjectFlags(source) & 32 /* Mapped */ && getConstraintTypeFromMappedType(source) === getIndexType(target)) {
+                        if (!(getMappedTypeModifiers(source) & 4 /* IncludeOptional */)) {
+                            var templateType = getTemplateTypeFromMappedType(source);
+                            var indexedAccessType = getIndexedAccessType(target, getTypeParameterFromMappedType(source));
+                            if (result = isRelatedTo(templateType, indexedAccessType, reportErrors)) {
+                                return result;
+                            }
+                        }
+                    }
+                }
+                else if (target.flags & 1048576 /* Index */) {
+                    // A keyof S is related to a keyof T if T is related to S.
+                    if (source.flags & 1048576 /* Index */) {
+                        if (result = isRelatedTo(target.type, source.type, /*reportErrors*/ false)) {
+                            return result;
+                        }
+                    }
+                    // A type S is assignable to keyof T if S is assignable to keyof C, where C is the
+                    // simplified form of T or, if T doesn't simplify, the constraint of T.
+                    if (relation !== definitelyAssignableRelation) {
+                        var simplified = getSimplifiedType(target.type);
+                        var constraint = simplified !== target.type ? simplified : getConstraintOfType(target.type);
+                        if (constraint) {
+                            if (result = isRelatedTo(source, getIndexType(constraint, target.stringsOnly), reportErrors)) {
+                                return result;
+                            }
+                        }
+                    }
+                }
+                else if (target.flags & 2097152 /* IndexedAccess */) {
+                    // A type S is related to a type T[K] if S is related to C, where C is the
+                    // constraint of T[K]
+                    var constraint = getConstraintForRelation(target);
+                    if (constraint) {
+                        if (result = isRelatedTo(source, constraint, reportErrors)) {
+                            errorInfo = saveErrorInfo;
+                            return result;
+                        }
+                    }
+                }
+                else if (isGenericMappedType(target)) {
+                    // A source type T is related to a target type { [P in X]: T[P] }
+                    var template = getTemplateTypeFromMappedType(target);
+                    var modifiers = getMappedTypeModifiers(target);
+                    if (!(modifiers & 8 /* ExcludeOptional */)) {
+                        if (template.flags & 2097152 /* IndexedAccess */ && template.objectType === source &&
+                            template.indexType === getTypeParameterFromMappedType(target)) {
+                            return -1 /* True */;
+                        }
+                        // A source type T is related to a target type { [P in keyof T]: X } if T[P] is related to X.
+                        if (!isGenericMappedType(source) && getConstraintTypeFromMappedType(target) === getIndexType(source)) {
+                            var indexedAccessType = getIndexedAccessType(source, getTypeParameterFromMappedType(target));
+                            var templateType = getTemplateTypeFromMappedType(target);
+                            if (result = isRelatedTo(indexedAccessType, templateType, reportErrors)) {
+                                errorInfo = saveErrorInfo;
+                                return result;
+                            }
+                        }
+                    }
+                }
+                if (source.flags & 2162688 /* TypeVariable */) {
+                    if (source.flags & 2097152 /* IndexedAccess */ && target.flags & 2097152 /* IndexedAccess */) {
+                        // A type S[K] is related to a type T[J] if S is related to T and K is related to J.
+                        if (result = isRelatedTo(source.objectType, target.objectType, reportErrors)) {
+                            result &= isRelatedTo(source.indexType, target.indexType, reportErrors);
+                        }
+                        if (result) {
+                            errorInfo = saveErrorInfo;
+                            return result;
+                        }
+                    }
+                    var constraint = getConstraintForRelation(source);
+                    if (!constraint || (source.flags & 65536 /* TypeParameter */ && constraint.flags & 3 /* AnyOrUnknown */)) {
+                        // A type variable with no constraint is not related to the non-primitive object type.
+                        if (result = isRelatedTo(emptyObjectType, extractTypesOfKind(target, ~16777216 /* NonPrimitive */))) {
+                            errorInfo = saveErrorInfo;
+                            return result;
+                        }
+                    }
+                    else {
+                        var instantiated = getTypeWithThisArgument(constraint, source);
+                        if (result = isRelatedTo(instantiated, target, reportErrors)) {
+                            errorInfo = saveErrorInfo;
+                            return result;
+                        }
+                    }
+                }
+                else if (source.flags & 1048576 /* Index */) {
+                    if (result = isRelatedTo(keyofConstraintType, target, reportErrors)) {
+                        errorInfo = saveErrorInfo;
+                        return result;
+                    }
+                }
+                else if (source.flags & 4194304 /* Conditional */) {
+                    if (target.flags & 4194304 /* Conditional */) {
+                        // Two conditional types 'T1 extends U1 ? X1 : Y1' and 'T2 extends U2 ? X2 : Y2' are related if
+                        // one of T1 and T2 is related to the other, U1 and U2 are identical types, X1 is related to X2,
+                        // and Y1 is related to Y2.
+                        if (isTypeIdenticalTo(source.extendsType, target.extendsType) &&
+                            (isRelatedTo(source.checkType, target.checkType) || isRelatedTo(target.checkType, source.checkType))) {
+                            if (result = isRelatedTo(getTrueTypeFromConditionalType(source), getTrueTypeFromConditionalType(target), reportErrors)) {
+                                result &= isRelatedTo(getFalseTypeFromConditionalType(source), getFalseTypeFromConditionalType(target), reportErrors);
+                            }
+                            if (result) {
+                                errorInfo = saveErrorInfo;
+                                return result;
+                            }
+                        }
+                    }
+                    else if (relation !== definitelyAssignableRelation) {
+                        var distributiveConstraint = getConstraintOfDistributiveConditionalType(source);
+                        if (distributiveConstraint) {
+                            if (result = isRelatedTo(distributiveConstraint, target, reportErrors)) {
+                                errorInfo = saveErrorInfo;
+                                return result;
+                            }
+                        }
+                        var defaultConstraint = getDefaultConstraintOfConditionalType(source);
+                        if (defaultConstraint) {
+                            if (result = isRelatedTo(defaultConstraint, target, reportErrors)) {
+                                errorInfo = saveErrorInfo;
+                                return result;
+                            }
+                        }
+                    }
+                }
+                else {
+                    if (ts.getObjectFlags(source) & 4 /* Reference */ && ts.getObjectFlags(target) & 4 /* Reference */ && source.target === target.target &&
+                        !(ts.getObjectFlags(source) & 8192 /* MarkerType */ || ts.getObjectFlags(target) & 8192 /* MarkerType */)) {
+                        // We have type references to the same generic type, and the type references are not marker
+                        // type references (which are intended by be compared structurally). Obtain the variance
+                        // information for the type parameters and relate the type arguments accordingly.
+                        var variances = getVariances(source.target);
+                        if (result = typeArgumentsRelatedTo(source, target, variances, reportErrors)) {
+                            return result;
+                        }
+                        // The type arguments did not relate appropriately, but it may be because we have no variance
+                        // information (in which case typeArgumentsRelatedTo defaulted to covariance for all type
+                        // arguments). It might also be the case that the target type has a 'void' type argument for
+                        // a covariant type parameter that is only used in return positions within the generic type
+                        // (in which case any type argument is permitted on the source side). In those cases we proceed
+                        // with a structural comparison. Otherwise, we know for certain the instantiations aren't
+                        // related and we can return here.
+                        if (variances !== ts.emptyArray && !hasCovariantVoidArgument(target, variances)) {
+                            // In some cases generic types that are covariant in regular type checking mode become
+                            // invariant in --strictFunctionTypes mode because one or more type parameters are used in
+                            // both co- and contravariant positions. In order to make it easier to diagnose *why* such
+                            // types are invariant, if any of the type parameters are invariant we reset the reported
+                            // errors and instead force a structural comparison (which will include elaborations that
+                            // reveal the reason).
+                            if (!(reportErrors && ts.some(variances, function (v) { return v === 0 /* Invariant */; }))) {
+                                return 0 /* False */;
+                            }
+                            // We remember the original error information so we can restore it in case the structural
+                            // comparison unexpectedly succeeds. This can happen when the structural comparison result
+                            // is a Ternary.Maybe for example caused by the recursion depth limiter.
+                            originalErrorInfo = errorInfo;
+                            errorInfo = saveErrorInfo;
+                        }
+                    }
+                    // Even if relationship doesn't hold for unions, intersections, or generic type references,
+                    // it may hold in a structural comparison.
+                    var sourceIsPrimitive = !!(source.flags & 32764 /* Primitive */);
+                    if (relation !== identityRelation) {
+                        source = getApparentType(source);
+                    }
+                    // In a check of the form X = A & B, we will have previously checked if A relates to X or B relates
+                    // to X. Failing both of those we want to check if the aggregation of A and B's members structurally
+                    // relates to X. Thus, we include intersection types on the source side here.
+                    if (source.flags & (131072 /* Object */ | 524288 /* Intersection */) && target.flags & 131072 /* Object */) {
+                        // Report structural errors only if we haven't reported any errors yet
+                        var reportStructuralErrors = reportErrors && errorInfo === saveErrorInfo && !sourceIsPrimitive;
+                        // An empty object type is related to any mapped type that includes a '?' modifier.
+                        if (isPartialMappedType(target) && !isGenericMappedType(source) && isEmptyObjectType(source)) {
+                            result = -1 /* True */;
+                        }
+                        else if (isGenericMappedType(target)) {
+                            result = isGenericMappedType(source) ? mappedTypeRelatedTo(source, target, reportStructuralErrors) : 0 /* False */;
+                        }
+                        else {
+                            result = propertiesRelatedTo(source, target, reportStructuralErrors);
+                            if (result) {
+                                result &= signaturesRelatedTo(source, target, 0 /* Call */, reportStructuralErrors);
+                                if (result) {
+                                    result &= signaturesRelatedTo(source, target, 1 /* Construct */, reportStructuralErrors);
+                                    if (result) {
+                                        result &= indexTypesRelatedTo(source, target, 0 /* String */, sourceIsPrimitive, reportStructuralErrors);
+                                        if (result) {
+                                            result &= indexTypesRelatedTo(source, target, 1 /* Number */, sourceIsPrimitive, reportStructuralErrors);
+                                        }
+                                    }
+                                }
+                            }
+                        }
+                        if (result) {
+                            if (!originalErrorInfo) {
+                                errorInfo = saveErrorInfo;
+                                return result;
+                            }
+                            errorInfo = originalErrorInfo;
+                        }
+                    }
+                }
+                return 0 /* False */;
+            }
+            // A type [P in S]: X is related to a type [Q in T]: Y if T is related to S and X' is
+            // related to Y, where X' is an instantiation of X in which P is replaced with Q. Notice
+            // that S and T are contra-variant whereas X and Y are co-variant.
+            function mappedTypeRelatedTo(source, target, reportErrors) {
+                var modifiersRelated = relation === comparableRelation || (relation === identityRelation ? getMappedTypeModifiers(source) === getMappedTypeModifiers(target) :
+                    getCombinedMappedTypeOptionality(source) <= getCombinedMappedTypeOptionality(target));
+                if (modifiersRelated) {
+                    var result_2;
+                    if (result_2 = isRelatedTo(getConstraintTypeFromMappedType(target), getConstraintTypeFromMappedType(source), reportErrors)) {
+                        var mapper = createTypeMapper([getTypeParameterFromMappedType(source)], [getTypeParameterFromMappedType(target)]);
+                        return result_2 & isRelatedTo(instantiateType(getTemplateTypeFromMappedType(source), mapper), getTemplateTypeFromMappedType(target), reportErrors);
+                    }
+                }
+                return 0 /* False */;
+            }
+            function propertiesRelatedTo(source, target, reportErrors) {
+                if (relation === identityRelation) {
+                    return propertiesIdenticalTo(source, target);
+                }
+                var requireOptionalProperties = relation === subtypeRelation && !isObjectLiteralType(source) && !isEmptyArrayLiteralType(source);
+                var unmatchedProperty = getUnmatchedProperty(source, target, requireOptionalProperties);
+                if (unmatchedProperty) {
+                    if (reportErrors) {
+                        reportError(ts.Diagnostics.Property_0_is_missing_in_type_1, symbolToString(unmatchedProperty), typeToString(source));
+                    }
+                    return 0 /* False */;
+                }
+                if (isObjectLiteralType(target)) {
+                    for (var _i = 0, _a = getPropertiesOfType(source); _i < _a.length; _i++) {
+                        var sourceProp = _a[_i];
+                        if (!getPropertyOfObjectType(target, sourceProp.escapedName)) {
+                            var sourceType = getTypeOfSymbol(sourceProp);
+                            if (!(sourceType === undefinedType || sourceType === undefinedWideningType)) {
+                                if (reportErrors) {
+                                    reportError(ts.Diagnostics.Property_0_does_not_exist_on_type_1, symbolToString(sourceProp), typeToString(target));
+                                }
+                                return 0 /* False */;
+                            }
+                        }
+                    }
+                }
+                var result = -1 /* True */;
+                var properties = getPropertiesOfObjectType(target);
+                for (var _b = 0, properties_3 = properties; _b < properties_3.length; _b++) {
+                    var targetProp = properties_3[_b];
+                    if (!(targetProp.flags & 4194304 /* Prototype */)) {
+                        var sourceProp = getPropertyOfType(source, targetProp.escapedName);
+                        if (sourceProp && sourceProp !== targetProp) {
+                            if (isIgnoredJsxProperty(source, sourceProp, getTypeOfSymbol(targetProp))) {
+                                continue;
+                            }
+                            var sourcePropFlags = ts.getDeclarationModifierFlagsFromSymbol(sourceProp);
+                            var targetPropFlags = ts.getDeclarationModifierFlagsFromSymbol(targetProp);
+                            if (sourcePropFlags & 8 /* Private */ || targetPropFlags & 8 /* Private */) {
+                                var hasDifferingDeclarations = sourceProp.valueDeclaration !== targetProp.valueDeclaration;
+                                if (ts.getCheckFlags(sourceProp) & 256 /* ContainsPrivate */ && hasDifferingDeclarations) {
+                                    if (reportErrors) {
+                                        reportError(ts.Diagnostics.Property_0_has_conflicting_declarations_and_is_inaccessible_in_type_1, symbolToString(sourceProp), typeToString(source));
+                                    }
+                                    return 0 /* False */;
+                                }
+                                if (hasDifferingDeclarations) {
+                                    if (reportErrors) {
+                                        if (sourcePropFlags & 8 /* Private */ && targetPropFlags & 8 /* Private */) {
+                                            reportError(ts.Diagnostics.Types_have_separate_declarations_of_a_private_property_0, symbolToString(targetProp));
+                                        }
+                                        else {
+                                            reportError(ts.Diagnostics.Property_0_is_private_in_type_1_but_not_in_type_2, symbolToString(targetProp), typeToString(sourcePropFlags & 8 /* Private */ ? source : target), typeToString(sourcePropFlags & 8 /* Private */ ? target : source));
+                                        }
+                                    }
+                                    return 0 /* False */;
+                                }
+                            }
+                            else if (targetPropFlags & 16 /* Protected */) {
+                                if (!isValidOverrideOf(sourceProp, targetProp)) {
+                                    if (reportErrors) {
+                                        reportError(ts.Diagnostics.Property_0_is_protected_but_type_1_is_not_a_class_derived_from_2, symbolToString(targetProp), typeToString(getDeclaringClass(sourceProp) || source), typeToString(getDeclaringClass(targetProp) || target));
+                                    }
+                                    return 0 /* False */;
+                                }
+                            }
+                            else if (sourcePropFlags & 16 /* Protected */) {
+                                if (reportErrors) {
+                                    reportError(ts.Diagnostics.Property_0_is_protected_in_type_1_but_public_in_type_2, symbolToString(targetProp), typeToString(source), typeToString(target));
+                                }
+                                return 0 /* False */;
+                            }
+                            var related = isRelatedTo(getTypeOfSymbol(sourceProp), getTypeOfSymbol(targetProp), reportErrors);
+                            if (!related) {
+                                if (reportErrors) {
+                                    reportError(ts.Diagnostics.Types_of_property_0_are_incompatible, symbolToString(targetProp));
+                                }
+                                return 0 /* False */;
+                            }
+                            result &= related;
+                            // When checking for comparability, be more lenient with optional properties.
+                            if (relation !== comparableRelation && sourceProp.flags & 16777216 /* Optional */ && !(targetProp.flags & 16777216 /* Optional */)) {
+                                // TypeScript 1.0 spec (April 2014): 3.8.3
+                                // S is a subtype of a type T, and T is a supertype of S if ...
+                                // S' and T are object types and, for each member M in T..
+                                // M is a property and S' contains a property N where
+                                // if M is a required property, N is also a required property
+                                // (M - property in T)
+                                // (N - property in S)
+                                if (reportErrors) {
+                                    reportError(ts.Diagnostics.Property_0_is_optional_in_type_1_but_required_in_type_2, symbolToString(targetProp), typeToString(source), typeToString(target));
+                                }
+                                return 0 /* False */;
+                            }
+                        }
+                    }
+                }
+                return result;
+            }
+            /**
+             * A type is 'weak' if it is an object type with at least one optional property
+             * and no required properties, call/construct signatures or index signatures
+             */
+            function isWeakType(type) {
+                if (type.flags & 131072 /* Object */) {
+                    var resolved = resolveStructuredTypeMembers(type);
+                    return resolved.callSignatures.length === 0 && resolved.constructSignatures.length === 0 &&
+                        !resolved.stringIndexInfo && !resolved.numberIndexInfo &&
+                        resolved.properties.length > 0 &&
+                        ts.every(resolved.properties, function (p) { return !!(p.flags & 16777216 /* Optional */); });
+                }
+                if (type.flags & 524288 /* Intersection */) {
+                    return ts.every(type.types, isWeakType);
+                }
+                return false;
+            }
+            function hasCommonProperties(source, target) {
+                var isComparingJsxAttributes = !!(ts.getObjectFlags(source) & 4096 /* JsxAttributes */);
+                for (var _i = 0, _a = getPropertiesOfType(source); _i < _a.length; _i++) {
+                    var prop = _a[_i];
+                    if (isKnownProperty(target, prop.escapedName, isComparingJsxAttributes)) {
+                        return true;
+                    }
+                }
+                return false;
+            }
+            function propertiesIdenticalTo(source, target) {
+                if (!(source.flags & 131072 /* Object */ && target.flags & 131072 /* Object */)) {
+                    return 0 /* False */;
+                }
+                var sourceProperties = getPropertiesOfObjectType(source);
+                var targetProperties = getPropertiesOfObjectType(target);
+                if (sourceProperties.length !== targetProperties.length) {
+                    return 0 /* False */;
+                }
+                var result = -1 /* True */;
+                for (var _i = 0, sourceProperties_1 = sourceProperties; _i < sourceProperties_1.length; _i++) {
+                    var sourceProp = sourceProperties_1[_i];
+                    var targetProp = getPropertyOfObjectType(target, sourceProp.escapedName);
+                    if (!targetProp) {
+                        return 0 /* False */;
+                    }
+                    var related = compareProperties(sourceProp, targetProp, isRelatedTo);
+                    if (!related) {
+                        return 0 /* False */;
+                    }
+                    result &= related;
+                }
+                return result;
+            }
+            function signaturesRelatedTo(source, target, kind, reportErrors) {
+                if (relation === identityRelation) {
+                    return signaturesIdenticalTo(source, target, kind);
+                }
+                if (target === anyFunctionType || source === anyFunctionType) {
+                    return -1 /* True */;
+                }
+                var sourceSignatures = getSignaturesOfType(source, kind);
+                var targetSignatures = getSignaturesOfType(target, kind);
+                if (kind === 1 /* Construct */ && sourceSignatures.length && targetSignatures.length) {
+                    if (ts.isAbstractConstructorType(source) && !ts.isAbstractConstructorType(target)) {
+                        // An abstract constructor type is not assignable to a non-abstract constructor type
+                        // as it would otherwise be possible to new an abstract class. Note that the assignability
+                        // check we perform for an extends clause excludes construct signatures from the target,
+                        // so this check never proceeds.
+                        if (reportErrors) {
+                            reportError(ts.Diagnostics.Cannot_assign_an_abstract_constructor_type_to_a_non_abstract_constructor_type);
+                        }
+                        return 0 /* False */;
+                    }
+                    if (!constructorVisibilitiesAreCompatible(sourceSignatures[0], targetSignatures[0], reportErrors)) {
+                        return 0 /* False */;
+                    }
+                }
+                var result = -1 /* True */;
+                var saveErrorInfo = errorInfo;
+                if (ts.getObjectFlags(source) & 64 /* Instantiated */ && ts.getObjectFlags(target) & 64 /* Instantiated */ && source.symbol === target.symbol) {
+                    // We have instantiations of the same anonymous type (which typically will be the type of a
+                    // method). Simply do a pairwise comparison of the signatures in the two signature lists instead
+                    // of the much more expensive N * M comparison matrix we explore below. We erase type parameters
+                    // as they are known to always be the same.
+                    for (var i = 0; i < targetSignatures.length; i++) {
+                        var related = signatureRelatedTo(sourceSignatures[i], targetSignatures[i], /*erase*/ true, reportErrors);
+                        if (!related) {
+                            return 0 /* False */;
+                        }
+                        result &= related;
+                    }
+                }
+                else if (sourceSignatures.length === 1 && targetSignatures.length === 1) {
+                    // For simple functions (functions with a single signature) we only erase type parameters for
+                    // the comparable relation. Otherwise, if the source signature is generic, we instantiate it
+                    // in the context of the target signature before checking the relationship. Ideally we'd do
+                    // this regardless of the number of signatures, but the potential costs are prohibitive due
+                    // to the quadratic nature of the logic below.
+                    var eraseGenerics = relation === comparableRelation || !!compilerOptions.noStrictGenericChecks;
+                    result = signatureRelatedTo(sourceSignatures[0], targetSignatures[0], eraseGenerics, reportErrors);
+                }
+                else {
+                    outer: for (var _i = 0, targetSignatures_1 = targetSignatures; _i < targetSignatures_1.length; _i++) {
+                        var t = targetSignatures_1[_i];
+                        // Only elaborate errors from the first failure
+                        var shouldElaborateErrors = reportErrors;
+                        for (var _a = 0, sourceSignatures_1 = sourceSignatures; _a < sourceSignatures_1.length; _a++) {
+                            var s = sourceSignatures_1[_a];
+                            var related = signatureRelatedTo(s, t, /*erase*/ true, shouldElaborateErrors);
+                            if (related) {
+                                result &= related;
+                                errorInfo = saveErrorInfo;
+                                continue outer;
+                            }
+                            shouldElaborateErrors = false;
+                        }
+                        if (shouldElaborateErrors) {
+                            reportError(ts.Diagnostics.Type_0_provides_no_match_for_the_signature_1, typeToString(source), signatureToString(t, /*enclosingDeclaration*/ undefined, /*flags*/ undefined, kind));
+                        }
+                        return 0 /* False */;
+                    }
+                }
+                return result;
+            }
+            /**
+             * See signatureAssignableTo, compareSignaturesIdentical
+             */
+            function signatureRelatedTo(source, target, erase, reportErrors) {
+                return compareSignaturesRelated(erase ? getErasedSignature(source) : source, erase ? getErasedSignature(target) : target, 0 /* None */, /*ignoreReturnTypes*/ false, reportErrors, reportError, isRelatedTo);
+            }
+            function signaturesIdenticalTo(source, target, kind) {
+                var sourceSignatures = getSignaturesOfType(source, kind);
+                var targetSignatures = getSignaturesOfType(target, kind);
+                if (sourceSignatures.length !== targetSignatures.length) {
+                    return 0 /* False */;
+                }
+                var result = -1 /* True */;
+                for (var i = 0; i < sourceSignatures.length; i++) {
+                    var related = compareSignaturesIdentical(sourceSignatures[i], targetSignatures[i], /*partialMatch*/ false, /*ignoreThisTypes*/ false, /*ignoreReturnTypes*/ false, isRelatedTo);
+                    if (!related) {
+                        return 0 /* False */;
+                    }
+                    result &= related;
+                }
+                return result;
+            }
+            function eachPropertyRelatedTo(source, target, kind, reportErrors) {
+                var result = -1 /* True */;
+                for (var _i = 0, _a = getPropertiesOfObjectType(source); _i < _a.length; _i++) {
+                    var prop = _a[_i];
+                    if (isIgnoredJsxProperty(source, prop, /*targetMemberType*/ undefined)) {
+                        continue;
+                    }
+                    // Skip over symbol-named members
+                    if (prop.nameType && prop.nameType.flags & 2048 /* UniqueESSymbol */) {
+                        continue;
+                    }
+                    if (kind === 0 /* String */ || isNumericLiteralName(prop.escapedName)) {
+                        var related = isRelatedTo(getTypeOfSymbol(prop), target, reportErrors);
+                        if (!related) {
+                            if (reportErrors) {
+                                reportError(ts.Diagnostics.Property_0_is_incompatible_with_index_signature, symbolToString(prop));
+                            }
+                            return 0 /* False */;
+                        }
+                        result &= related;
+                    }
+                }
+                return result;
+            }
+            function indexInfoRelatedTo(sourceInfo, targetInfo, reportErrors) {
+                var related = isRelatedTo(sourceInfo.type, targetInfo.type, reportErrors);
+                if (!related && reportErrors) {
+                    reportError(ts.Diagnostics.Index_signatures_are_incompatible);
+                }
+                return related;
+            }
+            function indexTypesRelatedTo(source, target, kind, sourceIsPrimitive, reportErrors) {
+                if (relation === identityRelation) {
+                    return indexTypesIdenticalTo(source, target, kind);
+                }
+                var targetInfo = getIndexInfoOfType(target, kind);
+                if (!targetInfo || targetInfo.type.flags & 3 /* AnyOrUnknown */ && !sourceIsPrimitive) {
+                    // Index signature of type any permits assignment from everything but primitives
+                    return -1 /* True */;
+                }
+                var sourceInfo = getIndexInfoOfType(source, kind) ||
+                    kind === 1 /* Number */ && getIndexInfoOfType(source, 0 /* String */);
+                if (sourceInfo) {
+                    return indexInfoRelatedTo(sourceInfo, targetInfo, reportErrors);
+                }
+                if (isGenericMappedType(source)) {
+                    // A generic mapped type { [P in K]: T } is related to an index signature { [x: string]: U }
+                    // if T is related to U.
+                    return (kind === 0 /* String */ && isRelatedTo(getTemplateTypeFromMappedType(source), targetInfo.type, reportErrors)); // TODO: GH#18217
+                }
+                if (isObjectTypeWithInferableIndex(source)) {
+                    var related = -1 /* True */;
+                    if (kind === 0 /* String */) {
+                        var sourceNumberInfo = getIndexInfoOfType(source, 1 /* Number */);
+                        if (sourceNumberInfo) {
+                            related = indexInfoRelatedTo(sourceNumberInfo, targetInfo, reportErrors);
+                        }
+                    }
+                    if (related) {
+                        related &= eachPropertyRelatedTo(source, targetInfo.type, kind, reportErrors);
+                    }
+                    return related;
+                }
+                if (reportErrors) {
+                    reportError(ts.Diagnostics.Index_signature_is_missing_in_type_0, typeToString(source));
+                }
+                return 0 /* False */;
+            }
+            function indexTypesIdenticalTo(source, target, indexKind) {
+                var targetInfo = getIndexInfoOfType(target, indexKind);
+                var sourceInfo = getIndexInfoOfType(source, indexKind);
+                if (!sourceInfo && !targetInfo) {
+                    return -1 /* True */;
+                }
+                if (sourceInfo && targetInfo && sourceInfo.isReadonly === targetInfo.isReadonly) {
+                    return isRelatedTo(sourceInfo.type, targetInfo.type);
+                }
+                return 0 /* False */;
+            }
+            function constructorVisibilitiesAreCompatible(sourceSignature, targetSignature, reportErrors) {
+                if (!sourceSignature.declaration || !targetSignature.declaration) {
+                    return true;
+                }
+                var sourceAccessibility = ts.getSelectedModifierFlags(sourceSignature.declaration, 24 /* NonPublicAccessibilityModifier */);
+                var targetAccessibility = ts.getSelectedModifierFlags(targetSignature.declaration, 24 /* NonPublicAccessibilityModifier */);
+                // A public, protected and private signature is assignable to a private signature.
+                if (targetAccessibility === 8 /* Private */) {
+                    return true;
+                }
+                // A public and protected signature is assignable to a protected signature.
+                if (targetAccessibility === 16 /* Protected */ && sourceAccessibility !== 8 /* Private */) {
+                    return true;
+                }
+                // Only a public signature is assignable to public signature.
+                if (targetAccessibility !== 16 /* Protected */ && !sourceAccessibility) {
+                    return true;
+                }
+                if (reportErrors) {
+                    reportError(ts.Diagnostics.Cannot_assign_a_0_constructor_type_to_a_1_constructor_type, visibilityToString(sourceAccessibility), visibilityToString(targetAccessibility));
+                }
+                return false;
+            }
+        }
+        // Return a type reference where the source type parameter is replaced with the target marker
+        // type, and flag the result as a marker type reference.
+        function getMarkerTypeReference(type, source, target) {
+            var result = createTypeReference(type, ts.map(type.typeParameters, function (t) { return t === source ? target : t; }));
+            result.objectFlags |= 8192 /* MarkerType */;
+            return result;
+        }
+        // Return an array containing the variance of each type parameter. The variance is effectively
+        // a digest of the type comparisons that occur for each type argument when instantiations of the
+        // generic type are structurally compared. We infer the variance information by comparing
+        // instantiations of the generic type for type arguments with known relations. The function
+        // returns the emptyArray singleton if we're not in strictFunctionTypes mode or if the function
+        // has been invoked recursively for the given generic type.
+        function getVariances(type) {
+            if (!strictFunctionTypes) {
+                return ts.emptyArray;
+            }
+            var typeParameters = type.typeParameters || ts.emptyArray;
+            var variances = type.variances;
+            if (!variances) {
+                if (type === globalArrayType || type === globalReadonlyArrayType) {
+                    // Arrays are known to be covariant, no need to spend time computing this
+                    variances = [1 /* Covariant */];
+                }
+                else {
+                    // The emptyArray singleton is used to signal a recursive invocation.
+                    type.variances = ts.emptyArray;
+                    variances = [];
+                    for (var _i = 0, typeParameters_1 = typeParameters; _i < typeParameters_1.length; _i++) {
+                        var tp = typeParameters_1[_i];
+                        // We first compare instantiations where the type parameter is replaced with
+                        // marker types that have a known subtype relationship. From this we can infer
+                        // invariance, covariance, contravariance or bivariance.
+                        var typeWithSuper = getMarkerTypeReference(type, tp, markerSuperType);
+                        var typeWithSub = getMarkerTypeReference(type, tp, markerSubType);
+                        var variance = (isTypeAssignableTo(typeWithSub, typeWithSuper) ? 1 /* Covariant */ : 0) |
+                            (isTypeAssignableTo(typeWithSuper, typeWithSub) ? 2 /* Contravariant */ : 0);
+                        // If the instantiations appear to be related bivariantly it may be because the
+                        // type parameter is independent (i.e. it isn't witnessed anywhere in the generic
+                        // type). To determine this we compare instantiations where the type parameter is
+                        // replaced with marker types that are known to be unrelated.
+                        if (variance === 3 /* Bivariant */ && isTypeAssignableTo(getMarkerTypeReference(type, tp, markerOtherType), typeWithSuper)) {
+                            variance = 4 /* Independent */;
+                        }
+                        variances.push(variance);
+                    }
+                }
+                type.variances = variances;
+            }
+            return variances;
+        }
+        // Return true if the given type reference has a 'void' type argument for a covariant type parameter.
+        // See comment at call in recursiveTypeRelatedTo for when this case matters.
+        function hasCovariantVoidArgument(type, variances) {
+            for (var i = 0; i < variances.length; i++) {
+                if (variances[i] === 1 /* Covariant */ && type.typeArguments[i].flags & 4096 /* Void */) {
+                    return true;
+                }
+            }
+            return false;
+        }
+        function isUnconstrainedTypeParameter(type) {
+            return type.flags & 65536 /* TypeParameter */ && !getConstraintFromTypeParameter(type);
+        }
+        function isTypeReferenceWithGenericArguments(type) {
+            return !!(ts.getObjectFlags(type) & 4 /* Reference */) && ts.some(type.typeArguments, function (t) { return isUnconstrainedTypeParameter(t) || isTypeReferenceWithGenericArguments(t); });
+        }
+        /**
+         * getTypeReferenceId(A<T, number, U>) returns "111=0-12=1"
+         *   where A.id=111 and number.id=12
+         */
+        function getTypeReferenceId(type, typeParameters, depth) {
+            if (depth === void 0) { depth = 0; }
+            var result = "" + type.target.id;
+            for (var _i = 0, _a = type.typeArguments; _i < _a.length; _i++) {
+                var t = _a[_i];
+                if (isUnconstrainedTypeParameter(t)) {
+                    var index = typeParameters.indexOf(t);
+                    if (index < 0) {
+                        index = typeParameters.length;
+                        typeParameters.push(t);
+                    }
+                    result += "=" + index;
+                }
+                else if (depth < 4 && isTypeReferenceWithGenericArguments(t)) {
+                    result += "<" + getTypeReferenceId(t, typeParameters, depth + 1) + ">";
+                }
+                else {
+                    result += "-" + t.id;
+                }
+            }
+            return result;
+        }
+        /**
+         * To improve caching, the relation key for two generic types uses the target's id plus ids of the type parameters.
+         * For other cases, the types ids are used.
+         */
+        function getRelationKey(source, target, relation) {
+            if (relation === identityRelation && source.id > target.id) {
+                var temp = source;
+                source = target;
+                target = temp;
+            }
+            if (isTypeReferenceWithGenericArguments(source) && isTypeReferenceWithGenericArguments(target)) {
+                var typeParameters = [];
+                return getTypeReferenceId(source, typeParameters) + "," + getTypeReferenceId(target, typeParameters);
+            }
+            return source.id + "," + target.id;
+        }
+        // Invoke the callback for each underlying property symbol of the given symbol and return the first
+        // value that isn't undefined.
+        function forEachProperty(prop, callback) {
+            if (ts.getCheckFlags(prop) & 6 /* Synthetic */) {
+                for (var _i = 0, _a = prop.containingType.types; _i < _a.length; _i++) {
+                    var t = _a[_i];
+                    var p = getPropertyOfType(t, prop.escapedName);
+                    var result = p && forEachProperty(p, callback);
+                    if (result) {
+                        return result;
+                    }
+                }
+                return undefined;
+            }
+            return callback(prop);
+        }
+        // Return the declaring class type of a property or undefined if property not declared in class
+        function getDeclaringClass(prop) {
+            return prop.parent && prop.parent.flags & 32 /* Class */ ? getDeclaredTypeOfSymbol(getParentOfSymbol(prop)) : undefined;
+        }
+        // Return true if some underlying source property is declared in a class that derives
+        // from the given base class.
+        function isPropertyInClassDerivedFrom(prop, baseClass) {
+            return forEachProperty(prop, function (sp) {
+                var sourceClass = getDeclaringClass(sp);
+                return sourceClass ? hasBaseType(sourceClass, baseClass) : false;
+            });
+        }
+        // Return true if source property is a valid override of protected parts of target property.
+        function isValidOverrideOf(sourceProp, targetProp) {
+            return !forEachProperty(targetProp, function (tp) { return ts.getDeclarationModifierFlagsFromSymbol(tp) & 16 /* Protected */ ?
+                !isPropertyInClassDerivedFrom(sourceProp, getDeclaringClass(tp)) : false; });
+        }
+        // Return true if the given class derives from each of the declaring classes of the protected
+        // constituents of the given property.
+        function isClassDerivedFromDeclaringClasses(checkClass, prop) {
+            return forEachProperty(prop, function (p) { return ts.getDeclarationModifierFlagsFromSymbol(p) & 16 /* Protected */ ?
+                !hasBaseType(checkClass, getDeclaringClass(p)) : false; }) ? undefined : checkClass;
+        }
+        // Return true if the given type is deeply nested. We consider this to be the case when structural type comparisons
+        // for 5 or more occurrences or instantiations of the type have been recorded on the given stack. It is possible,
+        // though highly unlikely, for this test to be true in a situation where a chain of instantiations is not infinitely
+        // expanding. Effectively, we will generate a false positive when two types are structurally equal to at least 5
+        // levels, but unequal at some level beyond that.
+        function isDeeplyNestedType(type, stack, depth) {
+            // We track all object types that have an associated symbol (representing the origin of the type)
+            if (depth >= 5 && type.flags & 131072 /* Object */) {
+                var symbol = type.symbol;
+                if (symbol) {
+                    var count = 0;
+                    for (var i = 0; i < depth; i++) {
+                        var t = stack[i];
+                        if (t.flags & 131072 /* Object */ && t.symbol === symbol) {
+                            count++;
+                            if (count >= 5)
+                                return true;
+                        }
+                    }
+                }
+            }
+            return false;
+        }
+        function isPropertyIdenticalTo(sourceProp, targetProp) {
+            return compareProperties(sourceProp, targetProp, compareTypesIdentical) !== 0 /* False */;
+        }
+        function compareProperties(sourceProp, targetProp, compareTypes) {
+            // Two members are considered identical when
+            // - they are public properties with identical names, optionality, and types,
+            // - they are private or protected properties originating in the same declaration and having identical types
+            if (sourceProp === targetProp) {
+                return -1 /* True */;
+            }
+            var sourcePropAccessibility = ts.getDeclarationModifierFlagsFromSymbol(sourceProp) & 24 /* NonPublicAccessibilityModifier */;
+            var targetPropAccessibility = ts.getDeclarationModifierFlagsFromSymbol(targetProp) & 24 /* NonPublicAccessibilityModifier */;
+            if (sourcePropAccessibility !== targetPropAccessibility) {
+                return 0 /* False */;
+            }
+            if (sourcePropAccessibility) {
+                if (getTargetSymbol(sourceProp) !== getTargetSymbol(targetProp)) {
+                    return 0 /* False */;
+                }
+            }
+            else {
+                if ((sourceProp.flags & 16777216 /* Optional */) !== (targetProp.flags & 16777216 /* Optional */)) {
+                    return 0 /* False */;
+                }
+            }
+            if (isReadonlySymbol(sourceProp) !== isReadonlySymbol(targetProp)) {
+                return 0 /* False */;
+            }
+            return compareTypes(getTypeOfSymbol(sourceProp), getTypeOfSymbol(targetProp));
+        }
+        function isMatchingSignature(source, target, partialMatch) {
+            // A source signature matches a target signature if the two signatures have the same number of required,
+            // optional, and rest parameters.
+            if (source.parameters.length === target.parameters.length &&
+                source.minArgumentCount === target.minArgumentCount &&
+                source.hasRestParameter === target.hasRestParameter) {
+                return true;
+            }
+            // A source signature partially matches a target signature if the target signature has no fewer required
+            // parameters and no more overall parameters than the source signature (where a signature with a rest
+            // parameter is always considered to have more overall parameters than one without).
+            var sourceRestCount = source.hasRestParameter ? 1 : 0;
+            var targetRestCount = target.hasRestParameter ? 1 : 0;
+            if (partialMatch && source.minArgumentCount <= target.minArgumentCount && (sourceRestCount > targetRestCount ||
+                sourceRestCount === targetRestCount && source.parameters.length >= target.parameters.length)) {
+                return true;
+            }
+            return false;
+        }
+        /**
+         * See signatureRelatedTo, compareSignaturesIdentical
+         */
+        function compareSignaturesIdentical(source, target, partialMatch, ignoreThisTypes, ignoreReturnTypes, compareTypes) {
+            // TODO (drosen): De-duplicate code between related functions.
+            if (source === target) {
+                return -1 /* True */;
+            }
+            if (!(isMatchingSignature(source, target, partialMatch))) {
+                return 0 /* False */;
+            }
+            // Check that the two signatures have the same number of type parameters. We might consider
+            // also checking that any type parameter constraints match, but that would require instantiating
+            // the constraints with a common set of type arguments to get relatable entities in places where
+            // type parameters occur in the constraints. The complexity of doing that doesn't seem worthwhile,
+            // particularly as we're comparing erased versions of the signatures below.
+            if (ts.length(source.typeParameters) !== ts.length(target.typeParameters)) {
+                return 0 /* False */;
+            }
+            // Spec 1.0 Section 3.8.3 & 3.8.4:
+            // M and N (the signatures) are instantiated using type Any as the type argument for all type parameters declared by M and N
+            source = getErasedSignature(source);
+            target = getErasedSignature(target);
+            var result = -1 /* True */;
+            if (!ignoreThisTypes) {
+                var sourceThisType = getThisTypeOfSignature(source);
+                if (sourceThisType) {
+                    var targetThisType = getThisTypeOfSignature(target);
+                    if (targetThisType) {
+                        var related = compareTypes(sourceThisType, targetThisType);
+                        if (!related) {
+                            return 0 /* False */;
+                        }
+                        result &= related;
+                    }
+                }
+            }
+            var targetLen = target.parameters.length;
+            for (var i = 0; i < targetLen; i++) {
+                var s = isRestParameterIndex(source, i) ? getRestTypeOfSignature(source) : getTypeOfParameter(source.parameters[i]);
+                var t = isRestParameterIndex(target, i) ? getRestTypeOfSignature(target) : getTypeOfParameter(target.parameters[i]);
+                var related = compareTypes(s, t);
+                if (!related) {
+                    return 0 /* False */;
+                }
+                result &= related;
+            }
+            if (!ignoreReturnTypes) {
+                var sourceTypePredicate = getTypePredicateOfSignature(source);
+                var targetTypePredicate = getTypePredicateOfSignature(target);
+                result &= sourceTypePredicate !== undefined || targetTypePredicate !== undefined
+                    ? compareTypePredicatesIdentical(sourceTypePredicate, targetTypePredicate, compareTypes)
+                    // If they're both type predicates their return types will both be `boolean`, so no need to compare those.
+                    : compareTypes(getReturnTypeOfSignature(source), getReturnTypeOfSignature(target));
+            }
+            return result;
+        }
+        function compareTypePredicatesIdentical(source, target, compareTypes) {
+            return source === undefined || target === undefined || !typePredicateKindsMatch(source, target) ? 0 /* False */ : compareTypes(source.type, target.type);
+        }
+        function isRestParameterIndex(signature, parameterIndex) {
+            return signature.hasRestParameter && parameterIndex >= signature.parameters.length - 1;
+        }
+        function literalTypesWithSameBaseType(types) {
+            var commonBaseType;
+            for (var _i = 0, types_9 = types; _i < types_9.length; _i++) {
+                var t = types_9[_i];
+                var baseType = getBaseTypeOfLiteralType(t);
+                if (!commonBaseType) {
+                    commonBaseType = baseType;
+                }
+                if (baseType === t || baseType !== commonBaseType) {
+                    return false;
+                }
+            }
+            return true;
+        }
+        // When the candidate types are all literal types with the same base type, return a union
+        // of those literal types. Otherwise, return the leftmost type for which no type to the
+        // right is a supertype.
+        function getSupertypeOrUnion(types) {
+            return literalTypesWithSameBaseType(types) ?
+                getUnionType(types) :
+                ts.reduceLeft(types, function (s, t) { return isTypeSubtypeOf(s, t) ? t : s; });
+        }
+        function getCommonSupertype(types) {
+            if (!strictNullChecks) {
+                return getSupertypeOrUnion(types);
+            }
+            var primaryTypes = ts.filter(types, function (t) { return !(t.flags & 24576 /* Nullable */); });
+            return primaryTypes.length ?
+                getNullableType(getSupertypeOrUnion(primaryTypes), getFalsyFlagsOfTypes(types) & 24576 /* Nullable */) :
+                getUnionType(types, 2 /* Subtype */);
+        }
+        // Return the leftmost type for which no type to the right is a subtype.
+        function getCommonSubtype(types) {
+            return ts.reduceLeft(types, function (s, t) { return isTypeSubtypeOf(t, s) ? t : s; });
+        }
+        function isArrayType(type) {
+            return !!(ts.getObjectFlags(type) & 4 /* Reference */) && type.target === globalArrayType;
+        }
+        function isArrayLikeType(type) {
+            // A type is array-like if it is a reference to the global Array or global ReadonlyArray type,
+            // or if it is not the undefined or null type and if it is assignable to ReadonlyArray<any>
+            return ts.getObjectFlags(type) & 4 /* Reference */ && (type.target === globalArrayType || type.target === globalReadonlyArrayType) ||
+                !(type.flags & 24576 /* Nullable */) && isTypeAssignableTo(type, anyReadonlyArrayType);
+        }
+        function isEmptyArrayLiteralType(type) {
+            var elementType = isArrayType(type) ? type.typeArguments[0] : undefined;
+            return elementType === undefinedWideningType || elementType === implicitNeverType;
+        }
+        function isTupleLikeType(type) {
+            return !!getPropertyOfType(type, "0");
+        }
+        function isNeitherUnitTypeNorNever(type) {
+            return !(type.flags & (27072 /* Unit */ | 32768 /* Never */));
+        }
+        function isUnitType(type) {
+            return !!(type.flags & 27072 /* Unit */);
+        }
+        function isLiteralType(type) {
+            return type.flags & 16 /* Boolean */ ? true :
+                type.flags & 262144 /* Union */ ? type.flags & 512 /* EnumLiteral */ ? true : ts.every(type.types, isUnitType) :
+                    isUnitType(type);
+        }
+        function getBaseTypeOfLiteralType(type) {
+            return type.flags & 512 /* EnumLiteral */ ? getBaseTypeOfEnumLiteralType(type) :
+                type.flags & 64 /* StringLiteral */ ? stringType :
+                    type.flags & 128 /* NumberLiteral */ ? numberType :
+                        type.flags & 256 /* BooleanLiteral */ ? booleanType :
+                            type.flags & 262144 /* Union */ ? getUnionType(ts.sameMap(type.types, getBaseTypeOfLiteralType)) :
+                                type;
+        }
+        function getWidenedLiteralType(type) {
+            return type.flags & 512 /* EnumLiteral */ ? getBaseTypeOfEnumLiteralType(type) :
+                type.flags & 64 /* StringLiteral */ && type.flags & 33554432 /* FreshLiteral */ ? stringType :
+                    type.flags & 128 /* NumberLiteral */ && type.flags & 33554432 /* FreshLiteral */ ? numberType :
+                        type.flags & 256 /* BooleanLiteral */ ? booleanType :
+                            type.flags & 262144 /* Union */ ? getUnionType(ts.sameMap(type.types, getWidenedLiteralType)) :
+                                type;
+        }
+        function getWidenedUniqueESSymbolType(type) {
+            return type.flags & 2048 /* UniqueESSymbol */ ? esSymbolType :
+                type.flags & 262144 /* Union */ ? getUnionType(ts.sameMap(type.types, getWidenedUniqueESSymbolType)) :
+                    type;
+        }
+        function getWidenedLiteralLikeTypeForContextualType(type, contextualType) {
+            if (!isLiteralOfContextualType(type, contextualType)) {
+                type = getWidenedUniqueESSymbolType(getWidenedLiteralType(type));
+            }
+            return type;
+        }
+        /**
+         * Check if a Type was written as a tuple type literal.
+         * Prefer using isTupleLikeType() unless the use of `elementTypes` is required.
+         */
+        function isTupleType(type) {
+            return !!(ts.getObjectFlags(type) & 4 /* Reference */ && type.target.objectFlags & 8 /* Tuple */);
+        }
+        function getFalsyFlagsOfTypes(types) {
+            var result = 0;
+            for (var _i = 0, types_10 = types; _i < types_10.length; _i++) {
+                var t = types_10[_i];
+                result |= getFalsyFlags(t);
+            }
+            return result;
+        }
+        // Returns the String, Number, Boolean, StringLiteral, NumberLiteral, BooleanLiteral, Void, Undefined, or Null
+        // flags for the string, number, boolean, "", 0, false, void, undefined, or null types respectively. Returns
+        // no flags for all other types (including non-falsy literal types).
+        function getFalsyFlags(type) {
+            return type.flags & 262144 /* Union */ ? getFalsyFlagsOfTypes(type.types) :
+                type.flags & 64 /* StringLiteral */ ? type.value === "" ? 64 /* StringLiteral */ : 0 :
+                    type.flags & 128 /* NumberLiteral */ ? type.value === 0 ? 128 /* NumberLiteral */ : 0 :
+                        type.flags & 256 /* BooleanLiteral */ ? type === falseType ? 256 /* BooleanLiteral */ : 0 :
+                            type.flags & 29148 /* PossiblyFalsy */;
+        }
+        function removeDefinitelyFalsyTypes(type) {
+            return getFalsyFlags(type) & 29120 /* DefinitelyFalsy */ ?
+                filterType(type, function (t) { return !(getFalsyFlags(t) & 29120 /* DefinitelyFalsy */); }) :
+                type;
+        }
+        function extractDefinitelyFalsyTypes(type) {
+            return mapType(type, getDefinitelyFalsyPartOfType);
+        }
+        function getDefinitelyFalsyPartOfType(type) {
+            return type.flags & 4 /* String */ ? emptyStringType :
+                type.flags & 8 /* Number */ ? zeroType :
+                    type.flags & 16 /* Boolean */ || type === falseType ? falseType :
+                        type.flags & (4096 /* Void */ | 8192 /* Undefined */ | 16384 /* Null */) ||
+                            type.flags & 64 /* StringLiteral */ && type.value === "" ||
+                            type.flags & 128 /* NumberLiteral */ && type.value === 0 ? type :
+                            neverType;
+        }
+        /**
+         * Add undefined or null or both to a type if they are missing.
+         * @param type - type to add undefined and/or null to if not present
+         * @param flags - Either TypeFlags.Undefined or TypeFlags.Null, or both
+         */
+        function getNullableType(type, flags) {
+            var missing = (flags & ~type.flags) & (8192 /* Undefined */ | 16384 /* Null */);
+            return missing === 0 ? type :
+                missing === 8192 /* Undefined */ ? getUnionType([type, undefinedType]) :
+                    missing === 16384 /* Null */ ? getUnionType([type, nullType]) :
+                        getUnionType([type, undefinedType, nullType]);
+        }
+        function getOptionalType(type) {
+            ts.Debug.assert(strictNullChecks);
+            return type.flags & 8192 /* Undefined */ ? type : getUnionType([type, undefinedType]);
+        }
+        function getGlobalNonNullableTypeInstantiation(type) {
+            if (!deferredGlobalNonNullableTypeAlias) {
+                deferredGlobalNonNullableTypeAlias = getGlobalSymbol("NonNullable", 524288 /* TypeAlias */, /*diagnostic*/ undefined) || unknownSymbol;
+            }
+            // Use NonNullable global type alias if available to improve quick info/declaration emit
+            if (deferredGlobalNonNullableTypeAlias !== unknownSymbol) {
+                return getTypeAliasInstantiation(deferredGlobalNonNullableTypeAlias, [type]);
+            }
+            return getTypeWithFacts(type, 524288 /* NEUndefinedOrNull */); // Type alias unavailable, fall back to non-higherorder behavior
+        }
+        function getNonNullableType(type) {
+            return strictNullChecks ? getGlobalNonNullableTypeInstantiation(type) : type;
+        }
+        /**
+         * Return true if type was inferred from an object literal, written as an object type literal, or is the shape of a module
+         * with no call or construct signatures.
+         */
+        function isObjectTypeWithInferableIndex(type) {
+            return type.symbol && (type.symbol.flags & (4096 /* ObjectLiteral */ | 2048 /* TypeLiteral */ | 512 /* ValueModule */)) !== 0 &&
+                !typeHasCallOrConstructSignatures(type);
+        }
+        function createSymbolWithType(source, type) {
+            var symbol = createSymbol(source.flags, source.escapedName);
+            symbol.declarations = source.declarations;
+            symbol.parent = source.parent;
+            symbol.type = type;
+            symbol.target = source;
+            if (source.valueDeclaration) {
+                symbol.valueDeclaration = source.valueDeclaration;
+            }
+            if (source.nameType) {
+                symbol.nameType = source.nameType;
+            }
+            return symbol;
+        }
+        function transformTypeOfMembers(type, f) {
+            var members = ts.createSymbolTable();
+            for (var _i = 0, _a = getPropertiesOfObjectType(type); _i < _a.length; _i++) {
+                var property = _a[_i];
+                var original = getTypeOfSymbol(property);
+                var updated = f(original);
+                members.set(property.escapedName, updated === original ? property : createSymbolWithType(property, updated));
+            }
+            return members;
+        }
+        /**
+         * If the the provided object literal is subject to the excess properties check,
+         * create a new that is exempt. Recursively mark object literal members as exempt.
+         * Leave signatures alone since they are not subject to the check.
+         */
+        function getRegularTypeOfObjectLiteral(type) {
+            if (!(isObjectLiteralType(type) && type.flags & 33554432 /* FreshLiteral */)) {
+                return type;
+            }
+            var regularType = type.regularType;
+            if (regularType) {
+                return regularType;
+            }
+            var resolved = type;
+            var members = transformTypeOfMembers(type, getRegularTypeOfObjectLiteral);
+            var regularNew = createAnonymousType(resolved.symbol, members, resolved.callSignatures, resolved.constructSignatures, resolved.stringIndexInfo, resolved.numberIndexInfo);
+            regularNew.flags = resolved.flags & ~33554432 /* FreshLiteral */;
+            regularNew.objectFlags |= 128 /* ObjectLiteral */;
+            type.regularType = regularNew;
+            return regularNew;
+        }
+        function createWideningContext(parent, propertyName, siblings) {
+            return { parent: parent, propertyName: propertyName, siblings: siblings, resolvedProperties: undefined };
+        }
+        function getSiblingsOfContext(context) {
+            if (!context.siblings) {
+                var siblings_1 = [];
+                for (var _i = 0, _a = getSiblingsOfContext(context.parent); _i < _a.length; _i++) {
+                    var type = _a[_i];
+                    if (isObjectLiteralType(type)) {
+                        var prop = getPropertyOfObjectType(type, context.propertyName);
+                        if (prop) {
+                            forEachType(getTypeOfSymbol(prop), function (t) {
+                                siblings_1.push(t);
+                            });
+                        }
+                    }
+                }
+                context.siblings = siblings_1;
+            }
+            return context.siblings;
+        }
+        function getPropertiesOfContext(context) {
+            if (!context.resolvedProperties) {
+                var names = ts.createMap();
+                for (var _i = 0, _a = getSiblingsOfContext(context); _i < _a.length; _i++) {
+                    var t = _a[_i];
+                    if (isObjectLiteralType(t) && !(ts.getObjectFlags(t) & 1024 /* ContainsSpread */)) {
+                        for (var _b = 0, _c = getPropertiesOfType(t); _b < _c.length; _b++) {
+                            var prop = _c[_b];
+                            names.set(prop.escapedName, prop);
+                        }
+                    }
+                }
+                context.resolvedProperties = ts.arrayFrom(names.values());
+            }
+            return context.resolvedProperties;
+        }
+        function getWidenedProperty(prop, context) {
+            if (!(prop.flags & 4 /* Property */)) {
+                // Since get accessors already widen their return value there is no need to
+                // widen accessor based properties here.
+                return prop;
+            }
+            if (prop.flags & 67108864 /* JSContainer */) {
+                var node = prop.declarations && ts.first(prop.declarations);
+                var init = ts.getAssignedJavascriptInitializer(node);
+                if (init && init.kind !== 184 /* ObjectLiteralExpression */) {
+                    // for JS special declarations, the only kind of initializer that will widen is object literals
+                    return prop;
+                }
+            }
+            var original = getTypeOfSymbol(prop);
+            var propContext = context && createWideningContext(context, prop.escapedName, /*siblings*/ undefined);
+            var widened = getWidenedTypeWithContext(original, propContext);
+            return widened === original ? prop : createSymbolWithType(prop, widened);
+        }
+        function getUndefinedProperty(prop) {
+            var cached = undefinedProperties.get(prop.escapedName);
+            if (cached) {
+                return cached;
+            }
+            var result = createSymbolWithType(prop, undefinedType);
+            result.flags |= 16777216 /* Optional */;
+            undefinedProperties.set(prop.escapedName, result);
+            return result;
+        }
+        function getWidenedTypeOfObjectLiteral(type, context) {
+            var members = ts.createSymbolTable();
+            for (var _i = 0, _a = getPropertiesOfObjectType(type); _i < _a.length; _i++) {
+                var prop = _a[_i];
+                members.set(prop.escapedName, getWidenedProperty(prop, context));
+            }
+            if (context) {
+                for (var _b = 0, _c = getPropertiesOfContext(context); _b < _c.length; _b++) {
+                    var prop = _c[_b];
+                    if (!members.has(prop.escapedName)) {
+                        members.set(prop.escapedName, getUndefinedProperty(prop));
+                    }
+                }
+            }
+            var stringIndexInfo = getIndexInfoOfType(type, 0 /* String */);
+            var numberIndexInfo = getIndexInfoOfType(type, 1 /* Number */);
+            return createAnonymousType(type.symbol, members, ts.emptyArray, ts.emptyArray, stringIndexInfo && createIndexInfo(getWidenedType(stringIndexInfo.type), stringIndexInfo.isReadonly), numberIndexInfo && createIndexInfo(getWidenedType(numberIndexInfo.type), numberIndexInfo.isReadonly));
+        }
+        function getWidenedType(type) {
+            return getWidenedTypeWithContext(type, /*context*/ undefined);
+        }
+        function getWidenedTypeWithContext(type, context) {
+            if (type.flags & 402653184 /* RequiresWidening */) {
+                if (type.flags & 24576 /* Nullable */) {
+                    return anyType;
+                }
+                if (isObjectLiteralType(type)) {
+                    return getWidenedTypeOfObjectLiteral(type, context);
+                }
+                if (type.flags & 262144 /* Union */) {
+                    var unionContext_1 = context || createWideningContext(/*parent*/ undefined, /*propertyName*/ undefined, type.types);
+                    var widenedTypes = ts.sameMap(type.types, function (t) { return t.flags & 24576 /* Nullable */ ? t : getWidenedTypeWithContext(t, unionContext_1); });
+                    // Widening an empty object literal transitions from a highly restrictive type to
+                    // a highly inclusive one. For that reason we perform subtype reduction here if the
+                    // union includes empty object types (e.g. reducing {} | string to just {}).
+                    return getUnionType(widenedTypes, ts.some(widenedTypes, isEmptyObjectType) ? 2 /* Subtype */ : 1 /* Literal */);
+                }
+                if (isArrayType(type) || isTupleType(type)) {
+                    return createTypeReference(type.target, ts.sameMap(type.typeArguments, getWidenedType));
+                }
+            }
+            return type;
+        }
+        /**
+         * Reports implicit any errors that occur as a result of widening 'null' and 'undefined'
+         * to 'any'. A call to reportWideningErrorsInType is normally accompanied by a call to
+         * getWidenedType. But in some cases getWidenedType is called without reporting errors
+         * (type argument inference is an example).
+         *
+         * The return value indicates whether an error was in fact reported. The particular circumstances
+         * are on a best effort basis. Currently, if the null or undefined that causes widening is inside
+         * an object literal property (arbitrarily deeply), this function reports an error. If no error is
+         * reported, reportImplicitAnyError is a suitable fallback to report a general error.
+         */
+        function reportWideningErrorsInType(type) {
+            var errorReported = false;
+            if (type.flags & 134217728 /* ContainsWideningType */) {
+                if (type.flags & 262144 /* Union */) {
+                    if (ts.some(type.types, isEmptyObjectType)) {
+                        errorReported = true;
+                    }
+                    else {
+                        for (var _i = 0, _a = type.types; _i < _a.length; _i++) {
+                            var t = _a[_i];
+                            if (reportWideningErrorsInType(t)) {
+                                errorReported = true;
+                            }
+                        }
+                    }
+                }
+                if (isArrayType(type) || isTupleType(type)) {
+                    for (var _b = 0, _c = type.typeArguments; _b < _c.length; _b++) {
+                        var t = _c[_b];
+                        if (reportWideningErrorsInType(t)) {
+                            errorReported = true;
+                        }
+                    }
+                }
+                if (isObjectLiteralType(type)) {
+                    for (var _d = 0, _e = getPropertiesOfObjectType(type); _d < _e.length; _d++) {
+                        var p = _e[_d];
+                        var t = getTypeOfSymbol(p);
+                        if (t.flags & 134217728 /* ContainsWideningType */) {
+                            if (!reportWideningErrorsInType(t)) {
+                                error(p.valueDeclaration, ts.Diagnostics.Object_literal_s_property_0_implicitly_has_an_1_type, symbolToString(p), typeToString(getWidenedType(t)));
+                            }
+                            errorReported = true;
+                        }
+                    }
+                }
+            }
+            return errorReported;
+        }
+        function reportImplicitAnyError(declaration, type) {
+            var typeAsString = typeToString(getWidenedType(type));
+            var diagnostic;
+            switch (declaration.kind) {
+                case 200 /* BinaryExpression */:
+                case 152 /* PropertyDeclaration */:
+                case 151 /* PropertySignature */:
+                    diagnostic = ts.Diagnostics.Member_0_implicitly_has_an_1_type;
+                    break;
+                case 149 /* Parameter */:
+                    diagnostic = declaration.dotDotDotToken ?
+                        ts.Diagnostics.Rest_parameter_0_implicitly_has_an_any_type :
+                        ts.Diagnostics.Parameter_0_implicitly_has_an_1_type;
+                    break;
+                case 182 /* BindingElement */:
+                    diagnostic = ts.Diagnostics.Binding_element_0_implicitly_has_an_1_type;
+                    break;
+                case 234 /* FunctionDeclaration */:
+                case 154 /* MethodDeclaration */:
+                case 153 /* MethodSignature */:
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                case 192 /* FunctionExpression */:
+                case 193 /* ArrowFunction */:
+                    if (!declaration.name) {
+                        error(declaration, ts.Diagnostics.Function_expression_which_lacks_return_type_annotation_implicitly_has_an_0_return_type, typeAsString);
+                        return;
+                    }
+                    diagnostic = ts.Diagnostics._0_which_lacks_return_type_annotation_implicitly_has_an_1_return_type;
+                    break;
+                case 177 /* MappedType */:
+                    error(declaration, ts.Diagnostics.Mapped_object_type_implicitly_has_an_any_template_type);
+                    return;
+                default:
+                    diagnostic = ts.Diagnostics.Variable_0_implicitly_has_an_1_type;
+            }
+            error(declaration, diagnostic, ts.declarationNameToString(ts.getNameOfDeclaration(declaration)), typeAsString);
+        }
+        function reportErrorsFromWidening(declaration, type) {
+            if (produceDiagnostics && noImplicitAny && type.flags & 134217728 /* ContainsWideningType */) {
+                // Report implicit any error within type if possible, otherwise report error on declaration
+                if (!reportWideningErrorsInType(type)) {
+                    reportImplicitAnyError(declaration, type);
+                }
+            }
+        }
+        function forEachMatchingParameterType(source, target, callback) {
+            var sourceMax = source.parameters.length;
+            var targetMax = target.parameters.length;
+            var count;
+            if (source.hasRestParameter && target.hasRestParameter) {
+                count = Math.max(sourceMax, targetMax);
+            }
+            else if (source.hasRestParameter) {
+                count = targetMax;
+            }
+            else if (target.hasRestParameter) {
+                count = sourceMax;
+            }
+            else {
+                count = Math.min(sourceMax, targetMax);
+            }
+            for (var i = 0; i < count; i++) {
+                callback(getTypeAtPosition(source, i), getTypeAtPosition(target, i));
+            }
+        }
+        function createInferenceContext(typeParameters, signature, flags, compareTypes, baseInferences) {
+            var inferences = baseInferences ? baseInferences.map(cloneInferenceInfo) : typeParameters.map(createInferenceInfo);
+            var context = mapper;
+            context.typeParameters = typeParameters;
+            context.signature = signature;
+            context.inferences = inferences;
+            context.flags = flags;
+            context.compareTypes = compareTypes || compareTypesAssignable;
+            return context;
+            function mapper(t) {
+                for (var i = 0; i < inferences.length; i++) {
+                    if (t === inferences[i].typeParameter) {
+                        inferences[i].isFixed = true;
+                        return getInferredType(context, i);
+                    }
+                }
+                return t;
+            }
+        }
+        function createInferenceInfo(typeParameter) {
+            return {
+                typeParameter: typeParameter,
+                candidates: undefined,
+                contraCandidates: undefined,
+                inferredType: undefined,
+                priority: undefined,
+                topLevel: true,
+                isFixed: false
+            };
+        }
+        function cloneInferenceInfo(inference) {
+            return {
+                typeParameter: inference.typeParameter,
+                candidates: inference.candidates && inference.candidates.slice(),
+                contraCandidates: inference.contraCandidates && inference.contraCandidates.slice(),
+                inferredType: inference.inferredType,
+                priority: inference.priority,
+                topLevel: inference.topLevel,
+                isFixed: inference.isFixed
+            };
+        }
+        // Return true if the given type could possibly reference a type parameter for which
+        // we perform type inference (i.e. a type parameter of a generic function). We cache
+        // results for union and intersection types for performance reasons.
+        function couldContainTypeVariables(type) {
+            var objectFlags = ts.getObjectFlags(type);
+            return !!(type.flags & 15794176 /* Instantiable */ ||
+                objectFlags & 4 /* Reference */ && ts.forEach(type.typeArguments, couldContainTypeVariables) ||
+                objectFlags & 16 /* Anonymous */ && type.symbol && type.symbol.flags & (16 /* Function */ | 8192 /* Method */ | 2048 /* TypeLiteral */ | 32 /* Class */) ||
+                objectFlags & 32 /* Mapped */ ||
+                type.flags & 786432 /* UnionOrIntersection */ && couldUnionOrIntersectionContainTypeVariables(type));
+        }
+        function couldUnionOrIntersectionContainTypeVariables(type) {
+            if (type.couldContainTypeVariables === undefined) {
+                type.couldContainTypeVariables = ts.some(type.types, couldContainTypeVariables);
+            }
+            return type.couldContainTypeVariables;
+        }
+        function isTypeParameterAtTopLevel(type, typeParameter) {
+            return type === typeParameter || !!(type.flags & 786432 /* UnionOrIntersection */) && ts.some(type.types, function (t) { return isTypeParameterAtTopLevel(t, typeParameter); });
+        }
+        /** Create an object with properties named in the string literal type. Every property has type `any` */
+        function createEmptyObjectTypeFromStringLiteral(type) {
+            var members = ts.createSymbolTable();
+            forEachType(type, function (t) {
+                if (!(t.flags & 64 /* StringLiteral */)) {
+                    return;
+                }
+                var name = ts.escapeLeadingUnderscores(t.value);
+                var literalProp = createSymbol(4 /* Property */, name);
+                literalProp.type = anyType;
+                if (t.symbol) {
+                    literalProp.declarations = t.symbol.declarations;
+                    literalProp.valueDeclaration = t.symbol.valueDeclaration;
+                }
+                members.set(name, literalProp);
+            });
+            var indexInfo = type.flags & 4 /* String */ ? createIndexInfo(emptyObjectType, /*isReadonly*/ false) : undefined;
+            return createAnonymousType(undefined, members, ts.emptyArray, ts.emptyArray, indexInfo, undefined);
+        }
+        /**
+         * Infer a suitable input type for a homomorphic mapped type { [P in keyof T]: X }. We construct
+         * an object type with the same set of properties as the source type, where the type of each
+         * property is computed by inferring from the source property type to X for the type
+         * variable T[P] (i.e. we treat the type T[P] as the type variable we're inferring for).
+         */
+        function inferTypeForHomomorphicMappedType(source, target) {
+            var key = source.id + "," + target.id;
+            if (reverseMappedCache.has(key)) {
+                return reverseMappedCache.get(key);
+            }
+            reverseMappedCache.set(key, undefined);
+            var type = createReverseMappedType(source, target);
+            reverseMappedCache.set(key, type);
+            return type;
+        }
+        function createReverseMappedType(source, target) {
+            var properties = getPropertiesOfType(source);
+            if (properties.length === 0 && !getIndexInfoOfType(source, 0 /* String */)) {
+                return undefined;
+            }
+            // If any property contains context sensitive functions that have been skipped, the source type
+            // is incomplete and we can't infer a meaningful input type.
+            for (var _i = 0, properties_4 = properties; _i < properties_4.length; _i++) {
+                var prop = properties_4[_i];
+                if (getTypeOfSymbol(prop).flags & 536870912 /* ContainsAnyFunctionType */) {
+                    return undefined;
+                }
+            }
+            var reversed = createObjectType(2048 /* ReverseMapped */ | 16 /* Anonymous */, /*symbol*/ undefined);
+            reversed.source = source;
+            reversed.mappedType = target;
+            return reversed;
+        }
+        function getTypeOfReverseMappedSymbol(symbol) {
+            return inferReverseMappedType(symbol.propertyType, symbol.mappedType);
+        }
+        function inferReverseMappedType(sourceType, target) {
+            var typeParameter = getIndexedAccessType(getConstraintTypeFromMappedType(target).type, getTypeParameterFromMappedType(target));
+            var templateType = getTemplateTypeFromMappedType(target);
+            var inference = createInferenceInfo(typeParameter);
+            inferTypes([inference], sourceType, templateType);
+            return getTypeFromInference(inference);
+        }
+        function getUnmatchedProperty(source, target, requireOptionalProperties) {
+            var properties = target.flags & 524288 /* Intersection */ ? getPropertiesOfUnionOrIntersectionType(target) : getPropertiesOfObjectType(target);
+            for (var _i = 0, properties_5 = properties; _i < properties_5.length; _i++) {
+                var targetProp = properties_5[_i];
+                if (requireOptionalProperties || !(targetProp.flags & 16777216 /* Optional */)) {
+                    var sourceProp = getPropertyOfType(source, targetProp.escapedName);
+                    if (!sourceProp) {
+                        return targetProp;
+                    }
+                }
+            }
+            return undefined;
+        }
+        function typesDefinitelyUnrelated(source, target) {
+            // Two tuple types with different arity are definitely unrelated.
+            // Two object types that each have a property that is unmatched in the other are definitely unrelated.
+            return isTupleType(source) && isTupleType(target) && getTypeReferenceArity(source) !== getTypeReferenceArity(target) ||
+                !!getUnmatchedProperty(source, target, /*requireOptionalProperties*/ false) && !!getUnmatchedProperty(target, source, /*requireOptionalProperties*/ false);
+        }
+        function getTypeFromInference(inference) {
+            return inference.candidates ? getUnionType(inference.candidates, 2 /* Subtype */) :
+                inference.contraCandidates ? getIntersectionType(inference.contraCandidates) :
+                    emptyObjectType;
+        }
+        function inferTypes(inferences, originalSource, originalTarget, priority) {
+            if (priority === void 0) { priority = 0; }
+            var symbolStack;
+            var visited;
+            var contravariant = false;
+            var propagationType;
+            inferFromTypes(originalSource, originalTarget);
+            function inferFromTypes(source, target) {
+                if (!couldContainTypeVariables(target)) {
+                    return;
+                }
+                if (source === wildcardType) {
+                    // We are inferring from an 'any' type. We want to infer this type for every type parameter
+                    // referenced in the target type, so we record it as the propagation type and infer from the
+                    // target to itself. Then, as we find candidates we substitute the propagation type.
+                    var savePropagationType = propagationType;
+                    propagationType = source;
+                    inferFromTypes(target, target);
+                    propagationType = savePropagationType;
+                    return;
+                }
+                if (source.aliasSymbol && source.aliasTypeArguments && source.aliasSymbol === target.aliasSymbol) {
+                    // Source and target are types originating in the same generic type alias declaration.
+                    // Simply infer from source type arguments to target type arguments.
+                    var sourceTypes = source.aliasTypeArguments;
+                    var targetTypes = target.aliasTypeArguments;
+                    for (var i = 0; i < sourceTypes.length; i++) {
+                        inferFromTypes(sourceTypes[i], targetTypes[i]);
+                    }
+                    return;
+                }
+                if (source.flags & 262144 /* Union */ && target.flags & 262144 /* Union */ && !(source.flags & 512 /* EnumLiteral */ && target.flags & 512 /* EnumLiteral */) ||
+                    source.flags & 524288 /* Intersection */ && target.flags & 524288 /* Intersection */) {
+                    // Source and target are both unions or both intersections. If source and target
+                    // are the same type, just relate each constituent type to itself.
+                    if (source === target) {
+                        for (var _i = 0, _a = source.types; _i < _a.length; _i++) {
+                            var t = _a[_i];
+                            inferFromTypes(t, t);
+                        }
+                        return;
+                    }
+                    // Find each source constituent type that has an identically matching target constituent
+                    // type, and for each such type infer from the type to itself. When inferring from a
+                    // type to itself we effectively find all type parameter occurrences within that type
+                    // and infer themselves as their type arguments. We have special handling for numeric
+                    // and string literals because the number and string types are not represented as unions
+                    // of all their possible values.
+                    var matchingTypes = void 0;
+                    for (var _b = 0, _c = source.types; _b < _c.length; _b++) {
+                        var t = _c[_b];
+                        if (typeIdenticalToSomeType(t, target.types)) {
+                            (matchingTypes || (matchingTypes = [])).push(t);
+                            inferFromTypes(t, t);
+                        }
+                        else if (t.flags & (128 /* NumberLiteral */ | 64 /* StringLiteral */)) {
+                            var b = getBaseTypeOfLiteralType(t);
+                            if (typeIdenticalToSomeType(b, target.types)) {
+                                (matchingTypes || (matchingTypes = [])).push(t, b);
+                            }
+                        }
+                    }
+                    // Next, to improve the quality of inferences, reduce the source and target types by
+                    // removing the identically matched constituents. For example, when inferring from
+                    // 'string | string[]' to 'string | T' we reduce the types to 'string[]' and 'T'.
+                    if (matchingTypes) {
+                        source = removeTypesFromUnionOrIntersection(source, matchingTypes);
+                        target = removeTypesFromUnionOrIntersection(target, matchingTypes);
+                    }
+                }
+                if (target.flags & 2162688 /* TypeVariable */) {
+                    // If target is a type parameter, make an inference, unless the source type contains
+                    // the anyFunctionType (the wildcard type that's used to avoid contextually typing functions).
+                    // Because the anyFunctionType is internal, it should not be exposed to the user by adding
+                    // it as an inference candidate. Hopefully, a better candidate will come along that does
+                    // not contain anyFunctionType when we come back to this argument for its second round
+                    // of inference. Also, we exclude inferences for silentNeverType (which is used as a wildcard
+                    // when constructing types from type parameters that had no inference candidates).
+                    if (source.flags & 536870912 /* ContainsAnyFunctionType */ || source === silentNeverType) {
+                        return;
+                    }
+                    var inference = getInferenceInfoForType(target);
+                    if (inference) {
+                        if (!inference.isFixed) {
+                            if (inference.priority === undefined || priority < inference.priority) {
+                                inference.candidates = undefined;
+                                inference.contraCandidates = undefined;
+                                inference.priority = priority;
+                            }
+                            if (priority === inference.priority) {
+                                var candidate = propagationType || source;
+                                if (contravariant) {
+                                    inference.contraCandidates = ts.append(inference.contraCandidates, candidate);
+                                }
+                                else {
+                                    inference.candidates = ts.append(inference.candidates, candidate);
+                                }
+                            }
+                            if (!(priority & 8 /* ReturnType */) && target.flags & 65536 /* TypeParameter */ && !isTypeParameterAtTopLevel(originalTarget, target)) {
+                                inference.topLevel = false;
+                            }
+                        }
+                        return;
+                    }
+                }
+                if (ts.getObjectFlags(source) & 4 /* Reference */ && ts.getObjectFlags(target) & 4 /* Reference */ && source.target === target.target) {
+                    // If source and target are references to the same generic type, infer from type arguments
+                    var sourceTypes = source.typeArguments || ts.emptyArray;
+                    var targetTypes = target.typeArguments || ts.emptyArray;
+                    var count = sourceTypes.length < targetTypes.length ? sourceTypes.length : targetTypes.length;
+                    var variances = getVariances(source.target);
+                    for (var i = 0; i < count; i++) {
+                        if (i < variances.length && variances[i] === 2 /* Contravariant */) {
+                            inferFromContravariantTypes(sourceTypes[i], targetTypes[i]);
+                        }
+                        else {
+                            inferFromTypes(sourceTypes[i], targetTypes[i]);
+                        }
+                    }
+                }
+                else if (source.flags & 1048576 /* Index */ && target.flags & 1048576 /* Index */) {
+                    contravariant = !contravariant;
+                    inferFromTypes(source.type, target.type);
+                    contravariant = !contravariant;
+                }
+                else if ((isLiteralType(source) || source.flags & 4 /* String */) && target.flags & 1048576 /* Index */) {
+                    var empty = createEmptyObjectTypeFromStringLiteral(source);
+                    contravariant = !contravariant;
+                    var savePriority = priority;
+                    priority |= 16 /* LiteralKeyof */;
+                    inferFromTypes(empty, target.type);
+                    priority = savePriority;
+                    contravariant = !contravariant;
+                }
+                else if (source.flags & 2097152 /* IndexedAccess */ && target.flags & 2097152 /* IndexedAccess */) {
+                    inferFromTypes(source.objectType, target.objectType);
+                    inferFromTypes(source.indexType, target.indexType);
+                }
+                else if (source.flags & 4194304 /* Conditional */ && target.flags & 4194304 /* Conditional */) {
+                    inferFromTypes(source.checkType, target.checkType);
+                    inferFromTypes(source.extendsType, target.extendsType);
+                    inferFromTypes(getTrueTypeFromConditionalType(source), getTrueTypeFromConditionalType(target));
+                    inferFromTypes(getFalseTypeFromConditionalType(source), getFalseTypeFromConditionalType(target));
+                }
+                else if (target.flags & 786432 /* UnionOrIntersection */) {
+                    var targetTypes = target.types;
+                    var typeVariableCount = 0;
+                    var typeVariable = void 0;
+                    // First infer to each type in union or intersection that isn't a type variable
+                    for (var _d = 0, targetTypes_3 = targetTypes; _d < targetTypes_3.length; _d++) {
+                        var t = targetTypes_3[_d];
+                        if (getInferenceInfoForType(t)) {
+                            typeVariable = t;
+                            typeVariableCount++;
+                        }
+                        else {
+                            inferFromTypes(source, t);
+                        }
+                    }
+                    // Next, if target containings a single naked type variable, make a secondary inference to that type
+                    // variable. This gives meaningful results for union types in co-variant positions and intersection
+                    // types in contra-variant positions (such as callback parameters).
+                    if (typeVariableCount === 1) {
+                        var savePriority = priority;
+                        priority |= 1 /* NakedTypeVariable */;
+                        inferFromTypes(source, typeVariable);
+                        priority = savePriority;
+                    }
+                }
+                else if (source.flags & 262144 /* Union */) {
+                    // Source is a union or intersection type, infer from each constituent type
+                    var sourceTypes = source.types;
+                    for (var _e = 0, sourceTypes_3 = sourceTypes; _e < sourceTypes_3.length; _e++) {
+                        var sourceType = sourceTypes_3[_e];
+                        inferFromTypes(sourceType, target);
+                    }
+                }
+                else {
+                    if (!(priority & 32 /* NoConstraints */ && source.flags & (524288 /* Intersection */ | 15794176 /* Instantiable */))) {
+                        source = getApparentType(source);
+                    }
+                    if (source.flags & (131072 /* Object */ | 524288 /* Intersection */)) {
+                        var key = source.id + "," + target.id;
+                        if (visited && visited.get(key)) {
+                            return;
+                        }
+                        (visited || (visited = ts.createMap())).set(key, true);
+                        // If we are already processing another target type with the same associated symbol (such as
+                        // an instantiation of the same generic type), we do not explore this target as it would yield
+                        // no further inferences. We exclude the static side of classes from this check since it shares
+                        // its symbol with the instance side which would lead to false positives.
+                        var isNonConstructorObject = target.flags & 131072 /* Object */ &&
+                            !(ts.getObjectFlags(target) & 16 /* Anonymous */ && target.symbol && target.symbol.flags & 32 /* Class */);
+                        var symbol = isNonConstructorObject ? target.symbol : undefined;
+                        if (symbol) {
+                            if (ts.contains(symbolStack, symbol)) {
+                                return;
+                            }
+                            (symbolStack || (symbolStack = [])).push(symbol);
+                            inferFromObjectTypes(source, target);
+                            symbolStack.pop();
+                        }
+                        else {
+                            inferFromObjectTypes(source, target);
+                        }
+                    }
+                }
+            }
+            function inferFromContravariantTypes(source, target) {
+                if (strictFunctionTypes || priority & 64 /* AlwaysStrict */) {
+                    contravariant = !contravariant;
+                    inferFromTypes(source, target);
+                    contravariant = !contravariant;
+                }
+                else {
+                    inferFromTypes(source, target);
+                }
+            }
+            function getInferenceInfoForType(type) {
+                if (type.flags & 2162688 /* TypeVariable */) {
+                    for (var _i = 0, inferences_1 = inferences; _i < inferences_1.length; _i++) {
+                        var inference = inferences_1[_i];
+                        if (type === inference.typeParameter) {
+                            return inference;
+                        }
+                    }
+                }
+                return undefined;
+            }
+            function inferFromObjectTypes(source, target) {
+                if (isGenericMappedType(source) && isGenericMappedType(target)) {
+                    // The source and target types are generic types { [P in S]: X } and { [P in T]: Y }, so we infer
+                    // from S to T and from X to Y.
+                    inferFromTypes(getConstraintTypeFromMappedType(source), getConstraintTypeFromMappedType(target));
+                    inferFromTypes(getTemplateTypeFromMappedType(source), getTemplateTypeFromMappedType(target));
+                }
+                if (ts.getObjectFlags(target) & 32 /* Mapped */) {
+                    var constraintType = getConstraintTypeFromMappedType(target);
+                    if (constraintType.flags & 1048576 /* Index */) {
+                        // We're inferring from some source type S to a homomorphic mapped type { [P in keyof T]: X },
+                        // where T is a type variable. Use inferTypeForHomomorphicMappedType to infer a suitable source
+                        // type and then make a secondary inference from that type to T. We make a secondary inference
+                        // such that direct inferences to T get priority over inferences to Partial<T>, for example.
+                        var inference = getInferenceInfoForType(constraintType.type);
+                        if (inference && !inference.isFixed) {
+                            var inferredType = inferTypeForHomomorphicMappedType(source, target);
+                            if (inferredType) {
+                                var savePriority = priority;
+                                priority |= 2 /* HomomorphicMappedType */;
+                                inferFromTypes(inferredType, inference.typeParameter);
+                                priority = savePriority;
+                            }
+                        }
+                        return;
+                    }
+                    if (constraintType.flags & 65536 /* TypeParameter */) {
+                        // We're inferring from some source type S to a mapped type { [P in T]: X }, where T is a type
+                        // parameter. Infer from 'keyof S' to T and infer from a union of each property type in S to X.
+                        var savePriority = priority;
+                        priority |= 4 /* MappedTypeConstraint */;
+                        inferFromTypes(getIndexType(source), constraintType);
+                        priority = savePriority;
+                        inferFromTypes(getUnionType(ts.map(getPropertiesOfType(source), getTypeOfSymbol)), getTemplateTypeFromMappedType(target));
+                        return;
+                    }
+                }
+                // Infer from the members of source and target only if the two types are possibly related
+                if (!typesDefinitelyUnrelated(source, target)) {
+                    inferFromProperties(source, target);
+                    inferFromSignatures(source, target, 0 /* Call */);
+                    inferFromSignatures(source, target, 1 /* Construct */);
+                    inferFromIndexTypes(source, target);
+                }
+            }
+            function inferFromProperties(source, target) {
+                var properties = getPropertiesOfObjectType(target);
+                for (var _i = 0, properties_6 = properties; _i < properties_6.length; _i++) {
+                    var targetProp = properties_6[_i];
+                    var sourceProp = getPropertyOfType(source, targetProp.escapedName);
+                    if (sourceProp) {
+                        inferFromTypes(getTypeOfSymbol(sourceProp), getTypeOfSymbol(targetProp));
+                    }
+                }
+            }
+            function inferFromSignatures(source, target, kind) {
+                var sourceSignatures = getSignaturesOfType(source, kind);
+                var targetSignatures = getSignaturesOfType(target, kind);
+                var sourceLen = sourceSignatures.length;
+                var targetLen = targetSignatures.length;
+                var len = sourceLen < targetLen ? sourceLen : targetLen;
+                for (var i = 0; i < len; i++) {
+                    inferFromSignature(getBaseSignature(sourceSignatures[sourceLen - len + i]), getBaseSignature(targetSignatures[targetLen - len + i]));
+                }
+            }
+            function inferFromSignature(source, target) {
+                forEachMatchingParameterType(source, target, inferFromContravariantTypes);
+                var sourceTypePredicate = getTypePredicateOfSignature(source);
+                var targetTypePredicate = getTypePredicateOfSignature(target);
+                if (sourceTypePredicate && targetTypePredicate && sourceTypePredicate.kind === targetTypePredicate.kind) {
+                    inferFromTypes(sourceTypePredicate.type, targetTypePredicate.type);
+                }
+                else {
+                    inferFromTypes(getReturnTypeOfSignature(source), getReturnTypeOfSignature(target));
+                }
+            }
+            function inferFromIndexTypes(source, target) {
+                var targetStringIndexType = getIndexTypeOfType(target, 0 /* String */);
+                if (targetStringIndexType) {
+                    var sourceIndexType = getIndexTypeOfType(source, 0 /* String */) ||
+                        getImplicitIndexTypeOfType(source, 0 /* String */);
+                    if (sourceIndexType) {
+                        inferFromTypes(sourceIndexType, targetStringIndexType);
+                    }
+                }
+                var targetNumberIndexType = getIndexTypeOfType(target, 1 /* Number */);
+                if (targetNumberIndexType) {
+                    var sourceIndexType = getIndexTypeOfType(source, 1 /* Number */) ||
+                        getIndexTypeOfType(source, 0 /* String */) ||
+                        getImplicitIndexTypeOfType(source, 1 /* Number */);
+                    if (sourceIndexType) {
+                        inferFromTypes(sourceIndexType, targetNumberIndexType);
+                    }
+                }
+            }
+        }
+        function typeIdenticalToSomeType(type, types) {
+            for (var _i = 0, types_11 = types; _i < types_11.length; _i++) {
+                var t = types_11[_i];
+                if (isTypeIdenticalTo(t, type)) {
+                    return true;
+                }
+            }
+            return false;
+        }
+        /**
+         * Return a new union or intersection type computed by removing a given set of types
+         * from a given union or intersection type.
+         */
+        function removeTypesFromUnionOrIntersection(type, typesToRemove) {
+            var reducedTypes = [];
+            for (var _i = 0, _a = type.types; _i < _a.length; _i++) {
+                var t = _a[_i];
+                if (!typeIdenticalToSomeType(t, typesToRemove)) {
+                    reducedTypes.push(t);
+                }
+            }
+            return type.flags & 262144 /* Union */ ? getUnionType(reducedTypes) : getIntersectionType(reducedTypes);
+        }
+        function hasPrimitiveConstraint(type) {
+            var constraint = getConstraintOfTypeParameter(type);
+            return !!constraint && maybeTypeOfKind(constraint, 32764 /* Primitive */ | 1048576 /* Index */);
+        }
+        function isObjectLiteralType(type) {
+            return !!(ts.getObjectFlags(type) & 128 /* ObjectLiteral */);
+        }
+        function widenObjectLiteralCandidates(candidates) {
+            if (candidates.length > 1) {
+                var objectLiterals = ts.filter(candidates, isObjectLiteralType);
+                if (objectLiterals.length) {
+                    var objectLiteralsType = getWidenedType(getUnionType(objectLiterals, 2 /* Subtype */));
+                    return ts.concatenate(ts.filter(candidates, function (t) { return !isObjectLiteralType(t); }), [objectLiteralsType]);
+                }
+            }
+            return candidates;
+        }
+        function getContravariantInference(inference) {
+            return inference.priority & 28 /* PriorityImpliesCombination */ ? getIntersectionType(inference.contraCandidates) : getCommonSubtype(inference.contraCandidates);
+        }
+        function getCovariantInference(inference, context, signature) {
+            // Extract all object literal types and replace them with a single widened and normalized type.
+            var candidates = widenObjectLiteralCandidates(inference.candidates);
+            // We widen inferred literal types if
+            // all inferences were made to top-level occurrences of the type parameter, and
+            // the type parameter has no constraint or its constraint includes no primitive or literal types, and
+            // the type parameter was fixed during inference or does not occur at top-level in the return type.
+            var primitiveConstraint = hasPrimitiveConstraint(inference.typeParameter);
+            var widenLiteralTypes = !primitiveConstraint && inference.topLevel &&
+                (inference.isFixed || !isTypeParameterAtTopLevel(getReturnTypeOfSignature(signature), inference.typeParameter));
+            var baseCandidates = primitiveConstraint ? ts.sameMap(candidates, getRegularTypeOfLiteralType) :
+                widenLiteralTypes ? ts.sameMap(candidates, getWidenedLiteralType) :
+                    candidates;
+            // If all inferences were made from contravariant positions, infer a common subtype. Otherwise, if
+            // union types were requested or if all inferences were made from the return type position, infer a
+            // union type. Otherwise, infer a common supertype.
+            var unwidenedType = context.flags & 1 /* InferUnionTypes */ || inference.priority & 28 /* PriorityImpliesCombination */ ?
+                getUnionType(baseCandidates, 2 /* Subtype */) :
+                getCommonSupertype(baseCandidates);
+            return getWidenedType(unwidenedType);
+        }
+        function getInferredType(context, index) {
+            var inference = context.inferences[index];
+            var inferredType = inference.inferredType;
+            if (!inferredType) {
+                var signature = context.signature;
+                if (signature) {
+                    if (inference.candidates) {
+                        inferredType = getCovariantInference(inference, context, signature);
+                        // If we have inferred 'never' but have contravariant candidates. To get a more specific type we
+                        // infer from the contravariant candidates instead.
+                        if (inferredType.flags & 32768 /* Never */ && inference.contraCandidates) {
+                            inferredType = getContravariantInference(inference);
+                        }
+                    }
+                    else if (inference.contraCandidates) {
+                        // We only have contravariant inferences, infer the best common subtype of those
+                        inferredType = getContravariantInference(inference);
+                    }
+                    else if (context.flags & 2 /* NoDefault */) {
+                        // We use silentNeverType as the wildcard that signals no inferences.
+                        inferredType = silentNeverType;
+                    }
+                    else {
+                        // Infer either the default or the empty object type when no inferences were
+                        // made. It is important to remember that in this case, inference still
+                        // succeeds, meaning there is no error for not having inference candidates. An
+                        // inference error only occurs when there are *conflicting* candidates, i.e.
+                        // candidates with no common supertype.
+                        var defaultType = getDefaultFromTypeParameter(inference.typeParameter);
+                        if (defaultType) {
+                            // Instantiate the default type. Any forward reference to a type
+                            // parameter should be instantiated to the empty object type.
+                            inferredType = instantiateType(defaultType, combineTypeMappers(createBackreferenceMapper(context.signature.typeParameters, index), context));
+                        }
+                        else {
+                            inferredType = getDefaultTypeArgumentType(!!(context.flags & 4 /* AnyDefault */));
+                        }
+                    }
+                }
+                else {
+                    inferredType = getTypeFromInference(inference);
+                }
+                inference.inferredType = inferredType;
+                var constraint = getConstraintOfTypeParameter(inference.typeParameter);
+                if (constraint) {
+                    var instantiatedConstraint = instantiateType(constraint, context);
+                    if (!context.compareTypes(inferredType, getTypeWithThisArgument(instantiatedConstraint, inferredType))) {
+                        inference.inferredType = inferredType = instantiatedConstraint;
+                    }
+                }
+            }
+            return inferredType;
+        }
+        function getDefaultTypeArgumentType(isInJavaScriptFile) {
+            return isInJavaScriptFile ? anyType : emptyObjectType;
+        }
+        function getInferredTypes(context) {
+            var result = [];
+            for (var i = 0; i < context.inferences.length; i++) {
+                result.push(getInferredType(context, i));
+            }
+            return result;
+        }
+        // EXPRESSION TYPE CHECKING
+        function getResolvedSymbol(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedSymbol) {
+                links.resolvedSymbol = !ts.nodeIsMissing(node) &&
+                    resolveName(node, node.escapedText, 67216319 /* Value */ | 1048576 /* ExportValue */, ts.Diagnostics.Cannot_find_name_0, node, !ts.isWriteOnlyAccess(node), 
+                    /*excludeGlobals*/ false, ts.Diagnostics.Cannot_find_name_0_Did_you_mean_1) || unknownSymbol;
+            }
+            return links.resolvedSymbol;
+        }
+        function isInTypeQuery(node) {
+            // TypeScript 1.0 spec (April 2014): 3.6.3
+            // A type query consists of the keyword typeof followed by an expression.
+            // The expression is restricted to a single identifier or a sequence of identifiers separated by periods
+            return !!ts.findAncestor(node, function (n) { return n.kind === 165 /* TypeQuery */ ? true : n.kind === 71 /* Identifier */ || n.kind === 146 /* QualifiedName */ ? false : "quit"; });
+        }
+        // Return the flow cache key for a "dotted name" (i.e. a sequence of identifiers
+        // separated by dots). The key consists of the id of the symbol referenced by the
+        // leftmost identifier followed by zero or more property names separated by dots.
+        // The result is undefined if the reference isn't a dotted name. We prefix nodes
+        // occurring in an apparent type position with '@' because the control flow type
+        // of such nodes may be based on the apparent type instead of the declared type.
+        function getFlowCacheKey(node) {
+            if (node.kind === 71 /* Identifier */) {
+                var symbol = getResolvedSymbol(node);
+                return symbol !== unknownSymbol ? (isConstraintPosition(node) ? "@" : "") + getSymbolId(symbol) : undefined;
+            }
+            if (node.kind === 99 /* ThisKeyword */) {
+                return "0";
+            }
+            if (node.kind === 185 /* PropertyAccessExpression */) {
+                var key = getFlowCacheKey(node.expression);
+                return key && key + "." + ts.idText(node.name);
+            }
+            if (node.kind === 182 /* BindingElement */) {
+                var container = node.parent.parent;
+                var key = container.kind === 182 /* BindingElement */ ? getFlowCacheKey(container) : (container.initializer && getFlowCacheKey(container.initializer));
+                var text = getBindingElementNameText(node);
+                var result = key && text && (key + "." + text);
+                return result;
+            }
+            return undefined;
+        }
+        function getBindingElementNameText(element) {
+            var parent = element.parent;
+            if (parent.kind === 180 /* ObjectBindingPattern */) {
+                var name = element.propertyName || element.name;
+                switch (name.kind) {
+                    case 71 /* Identifier */:
+                        return ts.idText(name);
+                    case 147 /* ComputedPropertyName */:
+                        return ts.isStringOrNumericLiteral(name.expression) ? name.expression.text : undefined;
+                    case 9 /* StringLiteral */:
+                    case 8 /* NumericLiteral */:
+                        return name.text;
+                    default:
+                        // Per types, array and object binding patterns remain, however they should never be present if propertyName is not defined
+                        ts.Debug.fail("Unexpected name kind for binding element name");
+                }
+            }
+            else {
+                return "" + parent.elements.indexOf(element);
+            }
+        }
+        function isMatchingReference(source, target) {
+            switch (source.kind) {
+                case 71 /* Identifier */:
+                    return target.kind === 71 /* Identifier */ && getResolvedSymbol(source) === getResolvedSymbol(target) ||
+                        (target.kind === 232 /* VariableDeclaration */ || target.kind === 182 /* BindingElement */) &&
+                            getExportSymbolOfValueSymbolIfExported(getResolvedSymbol(source)) === getSymbolOfNode(target);
+                case 99 /* ThisKeyword */:
+                    return target.kind === 99 /* ThisKeyword */;
+                case 97 /* SuperKeyword */:
+                    return target.kind === 97 /* SuperKeyword */;
+                case 185 /* PropertyAccessExpression */:
+                    return target.kind === 185 /* PropertyAccessExpression */ &&
+                        source.name.escapedText === target.name.escapedText &&
+                        isMatchingReference(source.expression, target.expression);
+                case 182 /* BindingElement */:
+                    if (target.kind !== 185 /* PropertyAccessExpression */)
+                        return false;
+                    var t = target;
+                    if (t.name.escapedText !== getBindingElementNameText(source))
+                        return false;
+                    if (source.parent.parent.kind === 182 /* BindingElement */ && isMatchingReference(source.parent.parent, t.expression)) {
+                        return true;
+                    }
+                    if (source.parent.parent.kind === 232 /* VariableDeclaration */) {
+                        var maybeId = source.parent.parent.initializer;
+                        return !!maybeId && isMatchingReference(maybeId, t.expression);
+                    }
+            }
+            return false;
+        }
+        function containsMatchingReference(source, target) {
+            while (source.kind === 185 /* PropertyAccessExpression */) {
+                source = source.expression;
+                if (isMatchingReference(source, target)) {
+                    return true;
+                }
+            }
+            return false;
+        }
+        // Return true if target is a property access xxx.yyy, source is a property access xxx.zzz, the declared
+        // type of xxx is a union type, and yyy is a property that is possibly a discriminant. We consider a property
+        // a possible discriminant if its type differs in the constituents of containing union type, and if every
+        // choice is a unit type or a union of unit types.
+        function containsMatchingReferenceDiscriminant(source, target) {
+            return target.kind === 185 /* PropertyAccessExpression */ &&
+                containsMatchingReference(source, target.expression) &&
+                isDiscriminantProperty(getDeclaredTypeOfReference(target.expression), target.name.escapedText);
+        }
+        function getDeclaredTypeOfReference(expr) {
+            if (expr.kind === 71 /* Identifier */) {
+                return getTypeOfSymbol(getResolvedSymbol(expr));
+            }
+            if (expr.kind === 185 /* PropertyAccessExpression */) {
+                var type = getDeclaredTypeOfReference(expr.expression);
+                return type && getTypeOfPropertyOfType(type, expr.name.escapedText);
+            }
+            return undefined;
+        }
+        function isDiscriminantProperty(type, name) {
+            if (type && type.flags & 262144 /* Union */) {
+                var prop = getUnionOrIntersectionProperty(type, name);
+                if (prop && ts.getCheckFlags(prop) & 2 /* SyntheticProperty */) {
+                    if (prop.isDiscriminantProperty === undefined) {
+                        prop.isDiscriminantProperty = !!(prop.checkFlags & 32 /* HasNonUniformType */) && isLiteralType(getTypeOfSymbol(prop));
+                    }
+                    return prop.isDiscriminantProperty;
+                }
+            }
+            return false;
+        }
+        function findDiscriminantProperties(sourceProperties, target) {
+            var result;
+            for (var _i = 0, sourceProperties_2 = sourceProperties; _i < sourceProperties_2.length; _i++) {
+                var sourceProperty = sourceProperties_2[_i];
+                if (isDiscriminantProperty(target, sourceProperty.escapedName)) {
+                    if (result) {
+                        result.push(sourceProperty);
+                        continue;
+                    }
+                    result = [sourceProperty];
+                }
+            }
+            return result;
+        }
+        function isOrContainsMatchingReference(source, target) {
+            return isMatchingReference(source, target) || containsMatchingReference(source, target);
+        }
+        function hasMatchingArgument(callExpression, reference) {
+            if (callExpression.arguments) {
+                for (var _i = 0, _a = callExpression.arguments; _i < _a.length; _i++) {
+                    var argument = _a[_i];
+                    if (isOrContainsMatchingReference(reference, argument)) {
+                        return true;
+                    }
+                }
+            }
+            if (callExpression.expression.kind === 185 /* PropertyAccessExpression */ &&
+                isOrContainsMatchingReference(reference, callExpression.expression.expression)) {
+                return true;
+            }
+            return false;
+        }
+        function getFlowNodeId(flow) {
+            if (!flow.id) {
+                flow.id = nextFlowId;
+                nextFlowId++;
+            }
+            return flow.id;
+        }
+        function typeMaybeAssignableTo(source, target) {
+            if (!(source.flags & 262144 /* Union */)) {
+                return isTypeAssignableTo(source, target);
+            }
+            for (var _i = 0, _a = source.types; _i < _a.length; _i++) {
+                var t = _a[_i];
+                if (isTypeAssignableTo(t, target)) {
+                    return true;
+                }
+            }
+            return false;
+        }
+        // Remove those constituent types of declaredType to which no constituent type of assignedType is assignable.
+        // For example, when a variable of type number | string | boolean is assigned a value of type number | boolean,
+        // we remove type string.
+        function getAssignmentReducedType(declaredType, assignedType) {
+            if (declaredType !== assignedType) {
+                if (assignedType.flags & 32768 /* Never */) {
+                    return assignedType;
+                }
+                var reducedType = filterType(declaredType, function (t) { return typeMaybeAssignableTo(assignedType, t); });
+                if (!(reducedType.flags & 32768 /* Never */)) {
+                    return reducedType;
+                }
+            }
+            return declaredType;
+        }
+        function getTypeFactsOfTypes(types) {
+            var result = 0 /* None */;
+            for (var _i = 0, types_12 = types; _i < types_12.length; _i++) {
+                var t = types_12[_i];
+                result |= getTypeFacts(t);
+            }
+            return result;
+        }
+        function isFunctionObjectType(type) {
+            // We do a quick check for a "bind" property before performing the more expensive subtype
+            // check. This gives us a quicker out in the common case where an object type is not a function.
+            var resolved = resolveStructuredTypeMembers(type);
+            return !!(resolved.callSignatures.length || resolved.constructSignatures.length ||
+                resolved.members.get("bind") && isTypeSubtypeOf(type, globalFunctionType));
+        }
+        function getTypeFacts(type) {
+            var flags = type.flags;
+            if (flags & 4 /* String */) {
+                return strictNullChecks ? 4079361 /* StringStrictFacts */ : 4194049 /* StringFacts */;
+            }
+            if (flags & 64 /* StringLiteral */) {
+                var isEmpty = type.value === "";
+                return strictNullChecks ?
+                    isEmpty ? 3030785 /* EmptyStringStrictFacts */ : 1982209 /* NonEmptyStringStrictFacts */ :
+                    isEmpty ? 3145473 /* EmptyStringFacts */ : 4194049 /* NonEmptyStringFacts */;
+            }
+            if (flags & (8 /* Number */ | 32 /* Enum */)) {
+                return strictNullChecks ? 4079234 /* NumberStrictFacts */ : 4193922 /* NumberFacts */;
+            }
+            if (flags & 128 /* NumberLiteral */) {
+                var isZero = type.value === 0;
+                return strictNullChecks ?
+                    isZero ? 3030658 /* ZeroStrictFacts */ : 1982082 /* NonZeroStrictFacts */ :
+                    isZero ? 3145346 /* ZeroFacts */ : 4193922 /* NonZeroFacts */;
+            }
+            if (flags & 16 /* Boolean */) {
+                return strictNullChecks ? 4078980 /* BooleanStrictFacts */ : 4193668 /* BooleanFacts */;
+            }
+            if (flags & 272 /* BooleanLike */) {
+                return strictNullChecks ?
+                    type === falseType ? 3030404 /* FalseStrictFacts */ : 1981828 /* TrueStrictFacts */ :
+                    type === falseType ? 3145092 /* FalseFacts */ : 4193668 /* TrueFacts */;
+            }
+            if (flags & 131072 /* Object */) {
+                return isFunctionObjectType(type) ?
+                    strictNullChecks ? 1970144 /* FunctionStrictFacts */ : 4181984 /* FunctionFacts */ :
+                    strictNullChecks ? 1972176 /* ObjectStrictFacts */ : 4184016 /* ObjectFacts */;
+            }
+            if (flags & (4096 /* Void */ | 8192 /* Undefined */)) {
+                return 2457472 /* UndefinedFacts */;
+            }
+            if (flags & 16384 /* Null */) {
+                return 2340752 /* NullFacts */;
+            }
+            if (flags & 3072 /* ESSymbolLike */) {
+                return strictNullChecks ? 1981320 /* SymbolStrictFacts */ : 4193160 /* SymbolFacts */;
+            }
+            if (flags & 16777216 /* NonPrimitive */) {
+                return strictNullChecks ? 1972176 /* ObjectStrictFacts */ : 4184016 /* ObjectFacts */;
+            }
+            if (flags & 15794176 /* Instantiable */) {
+                return getTypeFacts(getBaseConstraintOfType(type) || emptyObjectType);
+            }
+            if (flags & 786432 /* UnionOrIntersection */) {
+                return getTypeFactsOfTypes(type.types);
+            }
+            return 4194303 /* All */;
+        }
+        function getTypeWithFacts(type, include) {
+            return filterType(type, function (t) { return (getTypeFacts(t) & include) !== 0; });
+        }
+        function getTypeWithDefault(type, defaultExpression) {
+            if (defaultExpression) {
+                var defaultType = getTypeOfExpression(defaultExpression);
+                return getUnionType([getTypeWithFacts(type, 131072 /* NEUndefined */), defaultType]);
+            }
+            return type;
+        }
+        function getTypeOfDestructuredProperty(type, name) {
+            var text = ts.getTextOfPropertyName(name);
+            return getConstraintForLocation(getTypeOfPropertyOfType(type, text), name) ||
+                isNumericLiteralName(text) && getIndexTypeOfType(type, 1 /* Number */) ||
+                getIndexTypeOfType(type, 0 /* String */) ||
+                errorType;
+        }
+        function getTypeOfDestructuredArrayElement(type, index) {
+            return isTupleLikeType(type) && getTypeOfPropertyOfType(type, "" + index) ||
+                checkIteratedTypeOrElementType(type, /*errorNode*/ undefined, /*allowStringInput*/ false, /*allowAsyncIterables*/ false) ||
+                errorType;
+        }
+        function getTypeOfDestructuredSpreadExpression(type) {
+            return createArrayType(checkIteratedTypeOrElementType(type, /*errorNode*/ undefined, /*allowStringInput*/ false, /*allowAsyncIterables*/ false) || errorType);
+        }
+        function getAssignedTypeOfBinaryExpression(node) {
+            var isDestructuringDefaultAssignment = node.parent.kind === 183 /* ArrayLiteralExpression */ && isDestructuringAssignmentTarget(node.parent) ||
+                node.parent.kind === 270 /* PropertyAssignment */ && isDestructuringAssignmentTarget(node.parent.parent);
+            return isDestructuringDefaultAssignment ?
+                getTypeWithDefault(getAssignedType(node), node.right) :
+                getTypeOfExpression(node.right);
+        }
+        function isDestructuringAssignmentTarget(parent) {
+            return parent.parent.kind === 200 /* BinaryExpression */ && parent.parent.left === parent ||
+                parent.parent.kind === 222 /* ForOfStatement */ && parent.parent.initializer === parent;
+        }
+        function getAssignedTypeOfArrayLiteralElement(node, element) {
+            return getTypeOfDestructuredArrayElement(getAssignedType(node), node.elements.indexOf(element));
+        }
+        function getAssignedTypeOfSpreadExpression(node) {
+            return getTypeOfDestructuredSpreadExpression(getAssignedType(node.parent));
+        }
+        function getAssignedTypeOfPropertyAssignment(node) {
+            return getTypeOfDestructuredProperty(getAssignedType(node.parent), node.name);
+        }
+        function getAssignedTypeOfShorthandPropertyAssignment(node) {
+            return getTypeWithDefault(getAssignedTypeOfPropertyAssignment(node), node.objectAssignmentInitializer);
+        }
+        function getAssignedType(node) {
+            var parent = node.parent;
+            switch (parent.kind) {
+                case 221 /* ForInStatement */:
+                    return stringType;
+                case 222 /* ForOfStatement */:
+                    return checkRightHandSideOfForOf(parent.expression, parent.awaitModifier) || errorType;
+                case 200 /* BinaryExpression */:
+                    return getAssignedTypeOfBinaryExpression(parent);
+                case 194 /* DeleteExpression */:
+                    return undefinedType;
+                case 183 /* ArrayLiteralExpression */:
+                    return getAssignedTypeOfArrayLiteralElement(parent, node);
+                case 204 /* SpreadElement */:
+                    return getAssignedTypeOfSpreadExpression(parent);
+                case 270 /* PropertyAssignment */:
+                    return getAssignedTypeOfPropertyAssignment(parent);
+                case 271 /* ShorthandPropertyAssignment */:
+                    return getAssignedTypeOfShorthandPropertyAssignment(parent);
+            }
+            return errorType;
+        }
+        function getInitialTypeOfBindingElement(node) {
+            var pattern = node.parent;
+            var parentType = getInitialType(pattern.parent);
+            var type = pattern.kind === 180 /* ObjectBindingPattern */ ?
+                getTypeOfDestructuredProperty(parentType, node.propertyName || node.name) :
+                !node.dotDotDotToken ?
+                    getTypeOfDestructuredArrayElement(parentType, pattern.elements.indexOf(node)) :
+                    getTypeOfDestructuredSpreadExpression(parentType);
+            return getTypeWithDefault(type, node.initializer);
+        }
+        function getTypeOfInitializer(node) {
+            // Return the cached type if one is available. If the type of the variable was inferred
+            // from its initializer, we'll already have cached the type. Otherwise we compute it now
+            // without caching such that transient types are reflected.
+            var links = getNodeLinks(node);
+            return links.resolvedType || getTypeOfExpression(node);
+        }
+        function getInitialTypeOfVariableDeclaration(node) {
+            if (node.initializer) {
+                return getTypeOfInitializer(node.initializer);
+            }
+            if (node.parent.parent.kind === 221 /* ForInStatement */) {
+                return stringType;
+            }
+            if (node.parent.parent.kind === 222 /* ForOfStatement */) {
+                return checkRightHandSideOfForOf(node.parent.parent.expression, node.parent.parent.awaitModifier) || errorType;
+            }
+            return errorType;
+        }
+        function getInitialType(node) {
+            return node.kind === 232 /* VariableDeclaration */ ?
+                getInitialTypeOfVariableDeclaration(node) :
+                getInitialTypeOfBindingElement(node);
+        }
+        function getInitialOrAssignedType(node) {
+            return node.kind === 232 /* VariableDeclaration */ || node.kind === 182 /* BindingElement */ ?
+                getInitialType(node) :
+                getAssignedType(node);
+        }
+        function isEmptyArrayAssignment(node) {
+            return node.kind === 232 /* VariableDeclaration */ && node.initializer &&
+                isEmptyArrayLiteral(node.initializer) ||
+                node.kind !== 182 /* BindingElement */ && node.parent.kind === 200 /* BinaryExpression */ &&
+                    isEmptyArrayLiteral(node.parent.right);
+        }
+        function getReferenceCandidate(node) {
+            switch (node.kind) {
+                case 191 /* ParenthesizedExpression */:
+                    return getReferenceCandidate(node.expression);
+                case 200 /* BinaryExpression */:
+                    switch (node.operatorToken.kind) {
+                        case 58 /* EqualsToken */:
+                            return getReferenceCandidate(node.left);
+                        case 26 /* CommaToken */:
+                            return getReferenceCandidate(node.right);
+                    }
+            }
+            return node;
+        }
+        function getReferenceRoot(node) {
+            var parent = node.parent;
+            return parent.kind === 191 /* ParenthesizedExpression */ ||
+                parent.kind === 200 /* BinaryExpression */ && parent.operatorToken.kind === 58 /* EqualsToken */ && parent.left === node ||
+                parent.kind === 200 /* BinaryExpression */ && parent.operatorToken.kind === 26 /* CommaToken */ && parent.right === node ?
+                getReferenceRoot(parent) : node;
+        }
+        function getTypeOfSwitchClause(clause) {
+            if (clause.kind === 266 /* CaseClause */) {
+                return getRegularTypeOfLiteralType(getTypeOfExpression(clause.expression));
+            }
+            return neverType;
+        }
+        function getSwitchClauseTypes(switchStatement) {
+            var links = getNodeLinks(switchStatement);
+            if (!links.switchTypes) {
+                links.switchTypes = [];
+                for (var _i = 0, _a = switchStatement.caseBlock.clauses; _i < _a.length; _i++) {
+                    var clause = _a[_i];
+                    links.switchTypes.push(getTypeOfSwitchClause(clause));
+                }
+            }
+            return links.switchTypes;
+        }
+        function eachTypeContainedIn(source, types) {
+            return source.flags & 262144 /* Union */ ? !ts.forEach(source.types, function (t) { return !ts.contains(types, t); }) : ts.contains(types, source);
+        }
+        function isTypeSubsetOf(source, target) {
+            return source === target || target.flags & 262144 /* Union */ && isTypeSubsetOfUnion(source, target);
+        }
+        function isTypeSubsetOfUnion(source, target) {
+            if (source.flags & 262144 /* Union */) {
+                for (var _i = 0, _a = source.types; _i < _a.length; _i++) {
+                    var t = _a[_i];
+                    if (!containsType(target.types, t)) {
+                        return false;
+                    }
+                }
+                return true;
+            }
+            if (source.flags & 512 /* EnumLiteral */ && getBaseTypeOfEnumLiteralType(source) === target) {
+                return true;
+            }
+            return containsType(target.types, source);
+        }
+        function forEachType(type, f) {
+            return type.flags & 262144 /* Union */ ? ts.forEach(type.types, f) : f(type);
+        }
+        function filterType(type, f) {
+            if (type.flags & 262144 /* Union */) {
+                var types = type.types;
+                var filtered = ts.filter(types, f);
+                return filtered === types ? type : getUnionTypeFromSortedList(filtered, type.flags & 67108864 /* UnionOfUnitTypes */);
+            }
+            return f(type) ? type : neverType;
+        }
+        function mapType(type, mapper, noReductions) {
+            if (type.flags & 32768 /* Never */) {
+                return type;
+            }
+            if (!(type.flags & 262144 /* Union */)) {
+                return mapper(type);
+            }
+            var types = type.types;
+            var mappedType;
+            var mappedTypes;
+            for (var _i = 0, types_13 = types; _i < types_13.length; _i++) {
+                var current = types_13[_i];
+                var t = mapper(current);
+                if (t) {
+                    if (!mappedType) {
+                        mappedType = t;
+                    }
+                    else if (!mappedTypes) {
+                        mappedTypes = [mappedType, t];
+                    }
+                    else {
+                        mappedTypes.push(t);
+                    }
+                }
+            }
+            return mappedTypes ? getUnionType(mappedTypes, noReductions ? 0 /* None */ : 1 /* Literal */) : mappedType;
+        }
+        function extractTypesOfKind(type, kind) {
+            return filterType(type, function (t) { return (t.flags & kind) !== 0; });
+        }
+        // Return a new type in which occurrences of the string and number primitive types in
+        // typeWithPrimitives have been replaced with occurrences of string literals and numeric
+        // literals in typeWithLiterals, respectively.
+        function replacePrimitivesWithLiterals(typeWithPrimitives, typeWithLiterals) {
+            if (isTypeSubsetOf(stringType, typeWithPrimitives) && maybeTypeOfKind(typeWithLiterals, 64 /* StringLiteral */) ||
+                isTypeSubsetOf(numberType, typeWithPrimitives) && maybeTypeOfKind(typeWithLiterals, 128 /* NumberLiteral */)) {
+                return mapType(typeWithPrimitives, function (t) {
+                    return t.flags & 4 /* String */ ? extractTypesOfKind(typeWithLiterals, 4 /* String */ | 64 /* StringLiteral */) :
+                        t.flags & 8 /* Number */ ? extractTypesOfKind(typeWithLiterals, 8 /* Number */ | 128 /* NumberLiteral */) :
+                            t;
+                });
+            }
+            return typeWithPrimitives;
+        }
+        function isIncomplete(flowType) {
+            return flowType.flags === 0;
+        }
+        function getTypeFromFlowType(flowType) {
+            return flowType.flags === 0 ? flowType.type : flowType;
+        }
+        function createFlowType(type, incomplete) {
+            return incomplete ? { flags: 0, type: type } : type;
+        }
+        // An evolving array type tracks the element types that have so far been seen in an
+        // 'x.push(value)' or 'x[n] = value' operation along the control flow graph. Evolving
+        // array types are ultimately converted into manifest array types (using getFinalArrayType)
+        // and never escape the getFlowTypeOfReference function.
+        function createEvolvingArrayType(elementType) {
+            var result = createObjectType(256 /* EvolvingArray */);
+            result.elementType = elementType;
+            return result;
+        }
+        function getEvolvingArrayType(elementType) {
+            return evolvingArrayTypes[elementType.id] || (evolvingArrayTypes[elementType.id] = createEvolvingArrayType(elementType));
+        }
+        // When adding evolving array element types we do not perform subtype reduction. Instead,
+        // we defer subtype reduction until the evolving array type is finalized into a manifest
+        // array type.
+        function addEvolvingArrayElementType(evolvingArrayType, node) {
+            var elementType = getBaseTypeOfLiteralType(getContextFreeTypeOfExpression(node));
+            return isTypeSubsetOf(elementType, evolvingArrayType.elementType) ? evolvingArrayType : getEvolvingArrayType(getUnionType([evolvingArrayType.elementType, elementType]));
+        }
+        function createFinalArrayType(elementType) {
+            return elementType.flags & 32768 /* Never */ ?
+                autoArrayType :
+                createArrayType(elementType.flags & 262144 /* Union */ ?
+                    getUnionType(elementType.types, 2 /* Subtype */) :
+                    elementType);
+        }
+        // We perform subtype reduction upon obtaining the final array type from an evolving array type.
+        function getFinalArrayType(evolvingArrayType) {
+            return evolvingArrayType.finalArrayType || (evolvingArrayType.finalArrayType = createFinalArrayType(evolvingArrayType.elementType));
+        }
+        function finalizeEvolvingArrayType(type) {
+            return ts.getObjectFlags(type) & 256 /* EvolvingArray */ ? getFinalArrayType(type) : type;
+        }
+        function getElementTypeOfEvolvingArrayType(type) {
+            return ts.getObjectFlags(type) & 256 /* EvolvingArray */ ? type.elementType : neverType;
+        }
+        function isEvolvingArrayTypeList(types) {
+            var hasEvolvingArrayType = false;
+            for (var _i = 0, types_14 = types; _i < types_14.length; _i++) {
+                var t = types_14[_i];
+                if (!(t.flags & 32768 /* Never */)) {
+                    if (!(ts.getObjectFlags(t) & 256 /* EvolvingArray */)) {
+                        return false;
+                    }
+                    hasEvolvingArrayType = true;
+                }
+            }
+            return hasEvolvingArrayType;
+        }
+        // At flow control branch or loop junctions, if the type along every antecedent code path
+        // is an evolving array type, we construct a combined evolving array type. Otherwise we
+        // finalize all evolving array types.
+        function getUnionOrEvolvingArrayType(types, subtypeReduction) {
+            return isEvolvingArrayTypeList(types) ?
+                getEvolvingArrayType(getUnionType(ts.map(types, getElementTypeOfEvolvingArrayType))) :
+                getUnionType(ts.sameMap(types, finalizeEvolvingArrayType), subtypeReduction);
+        }
+        // Return true if the given node is 'x' in an 'x.length', x.push(value)', 'x.unshift(value)' or
+        // 'x[n] = value' operation, where 'n' is an expression of type any, undefined, or a number-like type.
+        function isEvolvingArrayOperationTarget(node) {
+            var root = getReferenceRoot(node);
+            var parent = root.parent;
+            var isLengthPushOrUnshift = parent.kind === 185 /* PropertyAccessExpression */ && (parent.name.escapedText === "length" ||
+                parent.parent.kind === 187 /* CallExpression */ && ts.isPushOrUnshiftIdentifier(parent.name));
+            var isElementAssignment = parent.kind === 186 /* ElementAccessExpression */ &&
+                parent.expression === root &&
+                parent.parent.kind === 200 /* BinaryExpression */ &&
+                parent.parent.operatorToken.kind === 58 /* EqualsToken */ &&
+                parent.parent.left === parent &&
+                !ts.isAssignmentTarget(parent.parent) &&
+                isTypeAssignableToKind(getTypeOfExpression(parent.argumentExpression), 168 /* NumberLike */);
+            return isLengthPushOrUnshift || isElementAssignment;
+        }
+        function maybeTypePredicateCall(node) {
+            var links = getNodeLinks(node);
+            if (links.maybeTypePredicate === undefined) {
+                links.maybeTypePredicate = getMaybeTypePredicate(node);
+            }
+            return links.maybeTypePredicate;
+        }
+        function getMaybeTypePredicate(node) {
+            if (node.expression.kind !== 97 /* SuperKeyword */) {
+                var funcType = checkNonNullExpression(node.expression);
+                if (funcType !== silentNeverType) {
+                    var apparentType = getApparentType(funcType);
+                    return apparentType !== errorType && ts.some(getSignaturesOfType(apparentType, 0 /* Call */), signatureHasTypePredicate);
+                }
+            }
+            return false;
+        }
+        function reportFlowControlError(node) {
+            var block = ts.findAncestor(node, ts.isFunctionOrModuleBlock);
+            var sourceFile = ts.getSourceFileOfNode(node);
+            var span = ts.getSpanOfTokenAtPosition(sourceFile, block.statements.pos);
+            diagnostics.add(ts.createFileDiagnostic(sourceFile, span.start, span.length, ts.Diagnostics.The_containing_function_or_module_body_is_too_large_for_control_flow_analysis));
+        }
+        function getFlowTypeOfReference(reference, declaredType, initialType, flowContainer, couldBeUninitialized) {
+            if (initialType === void 0) { initialType = declaredType; }
+            var key;
+            var flowDepth = 0;
+            if (flowAnalysisDisabled) {
+                return errorType;
+            }
+            if (!reference.flowNode || !couldBeUninitialized && !(declaredType.flags & 33492479 /* Narrowable */)) {
+                return declaredType;
+            }
+            var sharedFlowStart = sharedFlowCount;
+            var evolvedType = getTypeFromFlowType(getTypeAtFlowNode(reference.flowNode));
+            sharedFlowCount = sharedFlowStart;
+            // When the reference is 'x' in an 'x.length', 'x.push(value)', 'x.unshift(value)' or x[n] = value' operation,
+            // we give type 'any[]' to 'x' instead of using the type determined by control flow analysis such that operations
+            // on empty arrays are possible without implicit any errors and new element types can be inferred without
+            // type mismatch errors.
+            var resultType = ts.getObjectFlags(evolvedType) & 256 /* EvolvingArray */ && isEvolvingArrayOperationTarget(reference) ? anyArrayType : finalizeEvolvingArrayType(evolvedType);
+            if (reference.parent && reference.parent.kind === 209 /* NonNullExpression */ && getTypeWithFacts(resultType, 524288 /* NEUndefinedOrNull */).flags & 32768 /* Never */) {
+                return declaredType;
+            }
+            return resultType;
+            function getTypeAtFlowNode(flow) {
+                if (flowDepth === 2500) {
+                    // We have made 2500 recursive invocations. To avoid overflowing the call stack we report an error
+                    // and disable further control flow analysis in the containing function or module body.
+                    flowAnalysisDisabled = true;
+                    reportFlowControlError(reference);
+                    return errorType;
+                }
+                flowDepth++;
+                while (true) {
+                    var flags = flow.flags;
+                    if (flags & 1024 /* Shared */) {
+                        // We cache results of flow type resolution for shared nodes that were previously visited in
+                        // the same getFlowTypeOfReference invocation. A node is considered shared when it is the
+                        // antecedent of more than one node.
+                        for (var i = sharedFlowStart; i < sharedFlowCount; i++) {
+                            if (sharedFlowNodes[i] === flow) {
+                                flowDepth--;
+                                return sharedFlowTypes[i];
+                            }
+                        }
+                    }
+                    var type = void 0;
+                    if (flags & 4096 /* AfterFinally */) {
+                        // block flow edge: finally -> pre-try (for larger explanation check comment in binder.ts - bindTryStatement
+                        flow.locked = true;
+                        type = getTypeAtFlowNode(flow.antecedent);
+                        flow.locked = false;
+                    }
+                    else if (flags & 2048 /* PreFinally */) {
+                        // locked pre-finally flows are filtered out in getTypeAtFlowBranchLabel
+                        // so here just redirect to antecedent
+                        flow = flow.antecedent;
+                        continue;
+                    }
+                    else if (flags & 16 /* Assignment */) {
+                        type = getTypeAtFlowAssignment(flow);
+                        if (!type) {
+                            flow = flow.antecedent;
+                            continue;
+                        }
+                    }
+                    else if (flags & 96 /* Condition */) {
+                        type = getTypeAtFlowCondition(flow);
+                    }
+                    else if (flags & 128 /* SwitchClause */) {
+                        type = getTypeAtSwitchClause(flow);
+                    }
+                    else if (flags & 12 /* Label */) {
+                        if (flow.antecedents.length === 1) {
+                            flow = flow.antecedents[0];
+                            continue;
+                        }
+                        type = flags & 4 /* BranchLabel */ ?
+                            getTypeAtFlowBranchLabel(flow) :
+                            getTypeAtFlowLoopLabel(flow);
+                    }
+                    else if (flags & 256 /* ArrayMutation */) {
+                        type = getTypeAtFlowArrayMutation(flow);
+                        if (!type) {
+                            flow = flow.antecedent;
+                            continue;
+                        }
+                    }
+                    else if (flags & 2 /* Start */) {
+                        // Check if we should continue with the control flow of the containing function.
+                        var container = flow.container;
+                        if (container && container !== flowContainer && reference.kind !== 185 /* PropertyAccessExpression */ && reference.kind !== 99 /* ThisKeyword */) {
+                            flow = container.flowNode;
+                            continue;
+                        }
+                        // At the top of the flow we have the initial type.
+                        type = initialType;
+                    }
+                    else {
+                        // Unreachable code errors are reported in the binding phase. Here we
+                        // simply return the non-auto declared type to reduce follow-on errors.
+                        type = convertAutoToAny(declaredType);
+                    }
+                    if (flags & 1024 /* Shared */) {
+                        // Record visited node and the associated type in the cache.
+                        sharedFlowNodes[sharedFlowCount] = flow;
+                        sharedFlowTypes[sharedFlowCount] = type;
+                        sharedFlowCount++;
+                    }
+                    flowDepth--;
+                    return type;
+                }
+            }
+            function getTypeAtFlowAssignment(flow) {
+                var node = flow.node;
+                // Assignments only narrow the computed type if the declared type is a union type. Thus, we
+                // only need to evaluate the assigned type if the declared type is a union type.
+                if (isMatchingReference(reference, node)) {
+                    if (ts.getAssignmentTargetKind(node) === 2 /* Compound */) {
+                        var flowType = getTypeAtFlowNode(flow.antecedent);
+                        return createFlowType(getBaseTypeOfLiteralType(getTypeFromFlowType(flowType)), isIncomplete(flowType));
+                    }
+                    if (declaredType === autoType || declaredType === autoArrayType) {
+                        if (isEmptyArrayAssignment(node)) {
+                            return getEvolvingArrayType(neverType);
+                        }
+                        var assignedType = getBaseTypeOfLiteralType(getInitialOrAssignedType(node));
+                        return isTypeAssignableTo(assignedType, declaredType) ? assignedType : anyArrayType;
+                    }
+                    if (declaredType.flags & 262144 /* Union */) {
+                        return getAssignmentReducedType(declaredType, getInitialOrAssignedType(node));
+                    }
+                    return declaredType;
+                }
+                // We didn't have a direct match. However, if the reference is a dotted name, this
+                // may be an assignment to a left hand part of the reference. For example, for a
+                // reference 'x.y.z', we may be at an assignment to 'x.y' or 'x'. In that case,
+                // return the declared type.
+                if (containsMatchingReference(reference, node)) {
+                    return declaredType;
+                }
+                // Assignment doesn't affect reference
+                return undefined;
+            }
+            function getTypeAtFlowArrayMutation(flow) {
+                if (declaredType === autoType || declaredType === autoArrayType) {
+                    var node = flow.node;
+                    var expr = node.kind === 187 /* CallExpression */ ?
+                        node.expression.expression :
+                        node.left.expression;
+                    if (isMatchingReference(reference, getReferenceCandidate(expr))) {
+                        var flowType = getTypeAtFlowNode(flow.antecedent);
+                        var type = getTypeFromFlowType(flowType);
+                        if (ts.getObjectFlags(type) & 256 /* EvolvingArray */) {
+                            var evolvedType_1 = type;
+                            if (node.kind === 187 /* CallExpression */) {
+                                for (var _i = 0, _a = node.arguments; _i < _a.length; _i++) {
+                                    var arg = _a[_i];
+                                    evolvedType_1 = addEvolvingArrayElementType(evolvedType_1, arg);
+                                }
+                            }
+                            else {
+                                var indexType = getTypeOfExpression(node.left.argumentExpression);
+                                if (isTypeAssignableToKind(indexType, 168 /* NumberLike */)) {
+                                    evolvedType_1 = addEvolvingArrayElementType(evolvedType_1, node.right);
+                                }
+                            }
+                            return evolvedType_1 === type ? flowType : createFlowType(evolvedType_1, isIncomplete(flowType));
+                        }
+                        return flowType;
+                    }
+                }
+                return undefined;
+            }
+            function getTypeAtFlowCondition(flow) {
+                var flowType = getTypeAtFlowNode(flow.antecedent);
+                var type = getTypeFromFlowType(flowType);
+                if (type.flags & 32768 /* Never */) {
+                    return flowType;
+                }
+                // If we have an antecedent type (meaning we're reachable in some way), we first
+                // attempt to narrow the antecedent type. If that produces the never type, and if
+                // the antecedent type is incomplete (i.e. a transient type in a loop), then we
+                // take the type guard as an indication that control *could* reach here once we
+                // have the complete type. We proceed by switching to the silent never type which
+                // doesn't report errors when operators are applied to it. Note that this is the
+                // *only* place a silent never type is ever generated.
+                var assumeTrue = (flow.flags & 32 /* TrueCondition */) !== 0;
+                var nonEvolvingType = finalizeEvolvingArrayType(type);
+                var narrowedType = narrowType(nonEvolvingType, flow.expression, assumeTrue);
+                if (narrowedType === nonEvolvingType) {
+                    return flowType;
+                }
+                var incomplete = isIncomplete(flowType);
+                var resultType = incomplete && narrowedType.flags & 32768 /* Never */ ? silentNeverType : narrowedType;
+                return createFlowType(resultType, incomplete);
+            }
+            function getTypeAtSwitchClause(flow) {
+                var flowType = getTypeAtFlowNode(flow.antecedent);
+                var type = getTypeFromFlowType(flowType);
+                var expr = flow.switchStatement.expression;
+                if (isMatchingReference(reference, expr)) {
+                    type = narrowTypeBySwitchOnDiscriminant(type, flow.switchStatement, flow.clauseStart, flow.clauseEnd);
+                }
+                else if (isMatchingReferenceDiscriminant(expr, type)) {
+                    type = narrowTypeByDiscriminant(type, expr, function (t) { return narrowTypeBySwitchOnDiscriminant(t, flow.switchStatement, flow.clauseStart, flow.clauseEnd); });
+                }
+                return createFlowType(type, isIncomplete(flowType));
+            }
+            function getTypeAtFlowBranchLabel(flow) {
+                var antecedentTypes = [];
+                var subtypeReduction = false;
+                var seenIncomplete = false;
+                for (var _i = 0, _a = flow.antecedents; _i < _a.length; _i++) {
+                    var antecedent = _a[_i];
+                    if (antecedent.flags & 2048 /* PreFinally */ && antecedent.lock.locked) {
+                        // if flow correspond to branch from pre-try to finally and this branch is locked - this means that
+                        // we initially have started following the flow outside the finally block.
+                        // in this case we should ignore this branch.
+                        continue;
+                    }
+                    var flowType = getTypeAtFlowNode(antecedent);
+                    var type = getTypeFromFlowType(flowType);
+                    // If the type at a particular antecedent path is the declared type and the
+                    // reference is known to always be assigned (i.e. when declared and initial types
+                    // are the same), there is no reason to process more antecedents since the only
+                    // possible outcome is subtypes that will be removed in the final union type anyway.
+                    if (type === declaredType && declaredType === initialType) {
+                        return type;
+                    }
+                    ts.pushIfUnique(antecedentTypes, type);
+                    // If an antecedent type is not a subset of the declared type, we need to perform
+                    // subtype reduction. This happens when a "foreign" type is injected into the control
+                    // flow using the instanceof operator or a user defined type predicate.
+                    if (!isTypeSubsetOf(type, declaredType)) {
+                        subtypeReduction = true;
+                    }
+                    if (isIncomplete(flowType)) {
+                        seenIncomplete = true;
+                    }
+                }
+                return createFlowType(getUnionOrEvolvingArrayType(antecedentTypes, subtypeReduction ? 2 /* Subtype */ : 1 /* Literal */), seenIncomplete);
+            }
+            function getTypeAtFlowLoopLabel(flow) {
+                // If we have previously computed the control flow type for the reference at
+                // this flow loop junction, return the cached type.
+                var id = getFlowNodeId(flow);
+                var cache = flowLoopCaches[id] || (flowLoopCaches[id] = ts.createMap());
+                if (!key) {
+                    key = getFlowCacheKey(reference);
+                    // No cache key is generated when binding patterns are in unnarrowable situations
+                    if (!key) {
+                        return declaredType;
+                    }
+                }
+                var cached = cache.get(key);
+                if (cached) {
+                    return cached;
+                }
+                // If this flow loop junction and reference are already being processed, return
+                // the union of the types computed for each branch so far, marked as incomplete.
+                // It is possible to see an empty array in cases where loops are nested and the
+                // back edge of the outer loop reaches an inner loop that is already being analyzed.
+                // In such cases we restart the analysis of the inner loop, which will then see
+                // a non-empty in-process array for the outer loop and eventually terminate because
+                // the first antecedent of a loop junction is always the non-looping control flow
+                // path that leads to the top.
+                for (var i = flowLoopStart; i < flowLoopCount; i++) {
+                    if (flowLoopNodes[i] === flow && flowLoopKeys[i] === key && flowLoopTypes[i].length) {
+                        return createFlowType(getUnionOrEvolvingArrayType(flowLoopTypes[i], 1 /* Literal */), /*incomplete*/ true);
+                    }
+                }
+                // Add the flow loop junction and reference to the in-process stack and analyze
+                // each antecedent code path.
+                var antecedentTypes = [];
+                var subtypeReduction = false;
+                var firstAntecedentType;
+                flowLoopNodes[flowLoopCount] = flow;
+                flowLoopKeys[flowLoopCount] = key;
+                flowLoopTypes[flowLoopCount] = antecedentTypes;
+                for (var _i = 0, _a = flow.antecedents; _i < _a.length; _i++) {
+                    var antecedent = _a[_i];
+                    flowLoopCount++;
+                    var flowType = getTypeAtFlowNode(antecedent);
+                    flowLoopCount--;
+                    if (!firstAntecedentType) {
+                        firstAntecedentType = flowType;
+                    }
+                    var type = getTypeFromFlowType(flowType);
+                    // If we see a value appear in the cache it is a sign that control flow analysis
+                    // was restarted and completed by checkExpressionCached. We can simply pick up
+                    // the resulting type and bail out.
+                    var cached_1 = cache.get(key);
+                    if (cached_1) {
+                        return cached_1;
+                    }
+                    ts.pushIfUnique(antecedentTypes, type);
+                    // If an antecedent type is not a subset of the declared type, we need to perform
+                    // subtype reduction. This happens when a "foreign" type is injected into the control
+                    // flow using the instanceof operator or a user defined type predicate.
+                    if (!isTypeSubsetOf(type, declaredType)) {
+                        subtypeReduction = true;
+                    }
+                    // If the type at a particular antecedent path is the declared type there is no
+                    // reason to process more antecedents since the only possible outcome is subtypes
+                    // that will be removed in the final union type anyway.
+                    if (type === declaredType) {
+                        break;
+                    }
+                }
+                // The result is incomplete if the first antecedent (the non-looping control flow path)
+                // is incomplete.
+                var result = getUnionOrEvolvingArrayType(antecedentTypes, subtypeReduction ? 2 /* Subtype */ : 1 /* Literal */);
+                if (isIncomplete(firstAntecedentType)) {
+                    return createFlowType(result, /*incomplete*/ true);
+                }
+                cache.set(key, result);
+                return result;
+            }
+            function isMatchingReferenceDiscriminant(expr, computedType) {
+                return expr.kind === 185 /* PropertyAccessExpression */ &&
+                    computedType.flags & 262144 /* Union */ &&
+                    isMatchingReference(reference, expr.expression) &&
+                    isDiscriminantProperty(computedType, expr.name.escapedText);
+            }
+            function narrowTypeByDiscriminant(type, propAccess, narrowType) {
+                var propName = propAccess.name.escapedText;
+                var propType = getTypeOfPropertyOfType(type, propName);
+                var narrowedPropType = propType && narrowType(propType);
+                return propType === narrowedPropType ? type : filterType(type, function (t) { return isTypeComparableTo(getTypeOfPropertyOfType(t, propName), narrowedPropType); });
+            }
+            function narrowTypeByTruthiness(type, expr, assumeTrue) {
+                if (isMatchingReference(reference, expr)) {
+                    return getTypeWithFacts(type, assumeTrue ? 1048576 /* Truthy */ : 2097152 /* Falsy */);
+                }
+                if (isMatchingReferenceDiscriminant(expr, declaredType)) {
+                    return narrowTypeByDiscriminant(type, expr, function (t) { return getTypeWithFacts(t, assumeTrue ? 1048576 /* Truthy */ : 2097152 /* Falsy */); });
+                }
+                if (containsMatchingReferenceDiscriminant(reference, expr)) {
+                    return declaredType;
+                }
+                return type;
+            }
+            function isTypePresencePossible(type, propName, assumeTrue) {
+                if (getIndexInfoOfType(type, 0 /* String */)) {
+                    return true;
+                }
+                var prop = getPropertyOfType(type, propName);
+                if (prop) {
+                    return prop.flags & 16777216 /* Optional */ ? true : assumeTrue;
+                }
+                return !assumeTrue;
+            }
+            function narrowByInKeyword(type, literal, assumeTrue) {
+                if ((type.flags & (262144 /* Union */ | 131072 /* Object */)) || (type.flags & 65536 /* TypeParameter */ && type.isThisType)) {
+                    var propName_1 = ts.escapeLeadingUnderscores(literal.text);
+                    return filterType(type, function (t) { return isTypePresencePossible(t, propName_1, assumeTrue); });
+                }
+                return type;
+            }
+            function narrowTypeByBinaryExpression(type, expr, assumeTrue) {
+                switch (expr.operatorToken.kind) {
+                    case 58 /* EqualsToken */:
+                        return narrowTypeByTruthiness(type, expr.left, assumeTrue);
+                    case 32 /* EqualsEqualsToken */:
+                    case 33 /* ExclamationEqualsToken */:
+                    case 34 /* EqualsEqualsEqualsToken */:
+                    case 35 /* ExclamationEqualsEqualsToken */:
+                        var operator_1 = expr.operatorToken.kind;
+                        var left_1 = getReferenceCandidate(expr.left);
+                        var right_1 = getReferenceCandidate(expr.right);
+                        if (left_1.kind === 195 /* TypeOfExpression */ && ts.isStringLiteralLike(right_1)) {
+                            return narrowTypeByTypeof(type, left_1, operator_1, right_1, assumeTrue);
+                        }
+                        if (right_1.kind === 195 /* TypeOfExpression */ && ts.isStringLiteralLike(left_1)) {
+                            return narrowTypeByTypeof(type, right_1, operator_1, left_1, assumeTrue);
+                        }
+                        if (isMatchingReference(reference, left_1)) {
+                            return narrowTypeByEquality(type, operator_1, right_1, assumeTrue);
+                        }
+                        if (isMatchingReference(reference, right_1)) {
+                            return narrowTypeByEquality(type, operator_1, left_1, assumeTrue);
+                        }
+                        if (isMatchingReferenceDiscriminant(left_1, declaredType)) {
+                            return narrowTypeByDiscriminant(type, left_1, function (t) { return narrowTypeByEquality(t, operator_1, right_1, assumeTrue); });
+                        }
+                        if (isMatchingReferenceDiscriminant(right_1, declaredType)) {
+                            return narrowTypeByDiscriminant(type, right_1, function (t) { return narrowTypeByEquality(t, operator_1, left_1, assumeTrue); });
+                        }
+                        if (containsMatchingReferenceDiscriminant(reference, left_1) || containsMatchingReferenceDiscriminant(reference, right_1)) {
+                            return declaredType;
+                        }
+                        break;
+                    case 93 /* InstanceOfKeyword */:
+                        return narrowTypeByInstanceof(type, expr, assumeTrue);
+                    case 92 /* InKeyword */:
+                        var target = getReferenceCandidate(expr.right);
+                        if (ts.isStringLiteralLike(expr.left) && isMatchingReference(reference, target)) {
+                            return narrowByInKeyword(type, expr.left, assumeTrue);
+                        }
+                        break;
+                    case 26 /* CommaToken */:
+                        return narrowType(type, expr.right, assumeTrue);
+                }
+                return type;
+            }
+            function narrowTypeByEquality(type, operator, value, assumeTrue) {
+                if (type.flags & 1 /* Any */) {
+                    return type;
+                }
+                if (operator === 33 /* ExclamationEqualsToken */ || operator === 35 /* ExclamationEqualsEqualsToken */) {
+                    assumeTrue = !assumeTrue;
+                }
+                var valueType = getTypeOfExpression(value);
+                if (valueType.flags & 24576 /* Nullable */) {
+                    if (!strictNullChecks) {
+                        return type;
+                    }
+                    var doubleEquals = operator === 32 /* EqualsEqualsToken */ || operator === 33 /* ExclamationEqualsToken */;
+                    var facts = doubleEquals ?
+                        assumeTrue ? 65536 /* EQUndefinedOrNull */ : 524288 /* NEUndefinedOrNull */ :
+                        valueType.flags & 16384 /* Null */ ?
+                            assumeTrue ? 32768 /* EQNull */ : 262144 /* NENull */ :
+                            assumeTrue ? 16384 /* EQUndefined */ : 131072 /* NEUndefined */;
+                    return getTypeWithFacts(type, facts);
+                }
+                if (type.flags & 16909315 /* NotUnionOrUnit */) {
+                    return type;
+                }
+                if (assumeTrue) {
+                    var narrowedType = filterType(type, function (t) { return areTypesComparable(t, valueType); });
+                    return narrowedType.flags & 32768 /* Never */ ? type : replacePrimitivesWithLiterals(narrowedType, valueType);
+                }
+                if (isUnitType(valueType)) {
+                    var regularType_1 = getRegularTypeOfLiteralType(valueType);
+                    return filterType(type, function (t) { return getRegularTypeOfLiteralType(t) !== regularType_1; });
+                }
+                return type;
+            }
+            function narrowTypeByTypeof(type, typeOfExpr, operator, literal, assumeTrue) {
+                // We have '==', '!=', '====', or !==' operator with 'typeof xxx' and string literal operands
+                var target = getReferenceCandidate(typeOfExpr.expression);
+                if (!isMatchingReference(reference, target)) {
+                    // For a reference of the form 'x.y', a 'typeof x === ...' type guard resets the
+                    // narrowed type of 'y' to its declared type.
+                    if (containsMatchingReference(reference, target)) {
+                        return declaredType;
+                    }
+                    return type;
+                }
+                if (operator === 33 /* ExclamationEqualsToken */ || operator === 35 /* ExclamationEqualsEqualsToken */) {
+                    assumeTrue = !assumeTrue;
+                }
+                if (type.flags & 1 /* Any */ && literal.text === "function") {
+                    return type;
+                }
+                if (assumeTrue && !(type.flags & 262144 /* Union */)) {
+                    // We narrow a non-union type to an exact primitive type if the non-union type
+                    // is a supertype of that primitive type. For example, type 'any' can be narrowed
+                    // to one of the primitive types.
+                    var targetType = literal.text === "function" ? globalFunctionType : typeofTypesByName.get(literal.text);
+                    if (targetType) {
+                        if (isTypeSubtypeOf(targetType, type)) {
+                            return targetType;
+                        }
+                        if (type.flags & 15794176 /* Instantiable */) {
+                            var constraint = getBaseConstraintOfType(type) || anyType;
+                            if (isTypeSubtypeOf(targetType, constraint)) {
+                                return getIntersectionType([type, targetType]);
+                            }
+                        }
+                    }
+                }
+                var facts = assumeTrue ?
+                    typeofEQFacts.get(literal.text) || 64 /* TypeofEQHostObject */ :
+                    typeofNEFacts.get(literal.text) || 8192 /* TypeofNEHostObject */;
+                return getTypeWithFacts(type, facts);
+            }
+            function narrowTypeBySwitchOnDiscriminant(type, switchStatement, clauseStart, clauseEnd) {
+                // We only narrow if all case expressions specify values with unit types
+                var switchTypes = getSwitchClauseTypes(switchStatement);
+                if (!switchTypes.length) {
+                    return type;
+                }
+                var clauseTypes = switchTypes.slice(clauseStart, clauseEnd);
+                var hasDefaultClause = clauseStart === clauseEnd || ts.contains(clauseTypes, neverType);
+                var discriminantType = getUnionType(clauseTypes);
+                var caseType = discriminantType.flags & 32768 /* Never */ ? neverType :
+                    replacePrimitivesWithLiterals(filterType(type, function (t) { return areTypesComparable(discriminantType, t); }), discriminantType);
+                if (!hasDefaultClause) {
+                    return caseType;
+                }
+                var defaultType = filterType(type, function (t) { return !(isUnitType(t) && ts.contains(switchTypes, getRegularTypeOfLiteralType(t))); });
+                return caseType.flags & 32768 /* Never */ ? defaultType : getUnionType([caseType, defaultType]);
+            }
+            function narrowTypeByInstanceof(type, expr, assumeTrue) {
+                var left = getReferenceCandidate(expr.left);
+                if (!isMatchingReference(reference, left)) {
+                    // For a reference of the form 'x.y', an 'x instanceof T' type guard resets the
+                    // narrowed type of 'y' to its declared type.
+                    if (containsMatchingReference(reference, left)) {
+                        return declaredType;
+                    }
+                    return type;
+                }
+                // Check that right operand is a function type with a prototype property
+                var rightType = getTypeOfExpression(expr.right);
+                if (!isTypeSubtypeOf(rightType, globalFunctionType)) {
+                    return type;
+                }
+                var targetType;
+                var prototypeProperty = getPropertyOfType(rightType, "prototype");
+                if (prototypeProperty) {
+                    // Target type is type of the prototype property
+                    var prototypePropertyType = getTypeOfSymbol(prototypeProperty);
+                    if (!isTypeAny(prototypePropertyType)) {
+                        targetType = prototypePropertyType;
+                    }
+                }
+                // Don't narrow from 'any' if the target type is exactly 'Object' or 'Function'
+                if (isTypeAny(type) && (targetType === globalObjectType || targetType === globalFunctionType)) {
+                    return type;
+                }
+                if (!targetType) {
+                    // Target type is type of construct signature
+                    var constructSignatures = void 0;
+                    if (ts.getObjectFlags(rightType) & 2 /* Interface */) {
+                        constructSignatures = resolveDeclaredMembers(rightType).declaredConstructSignatures;
+                    }
+                    else if (ts.getObjectFlags(rightType) & 16 /* Anonymous */) {
+                        constructSignatures = getSignaturesOfType(rightType, 1 /* Construct */);
+                    }
+                    if (constructSignatures && constructSignatures.length) {
+                        targetType = getUnionType(ts.map(constructSignatures, function (signature) { return getReturnTypeOfSignature(getErasedSignature(signature)); }));
+                    }
+                }
+                if (targetType) {
+                    return getNarrowedType(type, targetType, assumeTrue, isTypeDerivedFrom);
+                }
+                return type;
+            }
+            function getNarrowedType(type, candidate, assumeTrue, isRelated) {
+                if (!assumeTrue) {
+                    return filterType(type, function (t) { return !isRelated(t, candidate); });
+                }
+                // If the current type is a union type, remove all constituents that couldn't be instances of
+                // the candidate type. If one or more constituents remain, return a union of those.
+                if (type.flags & 262144 /* Union */) {
+                    var assignableType = filterType(type, function (t) { return isRelated(t, candidate); });
+                    if (!(assignableType.flags & 32768 /* Never */)) {
+                        return assignableType;
+                    }
+                }
+                // If the candidate type is a subtype of the target type, narrow to the candidate type.
+                // Otherwise, if the target type is assignable to the candidate type, keep the target type.
+                // Otherwise, if the candidate type is assignable to the target type, narrow to the candidate
+                // type. Otherwise, the types are completely unrelated, so narrow to an intersection of the
+                // two types.
+                return isTypeSubtypeOf(candidate, type) ? candidate :
+                    isTypeAssignableTo(type, candidate) ? type :
+                        isTypeAssignableTo(candidate, type) ? candidate :
+                            getIntersectionType([type, candidate]);
+            }
+            function narrowTypeByTypePredicate(type, callExpression, assumeTrue) {
+                if (!hasMatchingArgument(callExpression, reference) || !maybeTypePredicateCall(callExpression)) {
+                    return type;
+                }
+                var signature = getResolvedSignature(callExpression);
+                var predicate = getTypePredicateOfSignature(signature);
+                if (!predicate) {
+                    return type;
+                }
+                // Don't narrow from 'any' if the predicate type is exactly 'Object' or 'Function'
+                if (isTypeAny(type) && (predicate.type === globalObjectType || predicate.type === globalFunctionType)) {
+                    return type;
+                }
+                if (ts.isIdentifierTypePredicate(predicate)) {
+                    var predicateArgument = callExpression.arguments[predicate.parameterIndex - (signature.thisParameter ? 1 : 0)];
+                    if (predicateArgument) {
+                        if (isMatchingReference(reference, predicateArgument)) {
+                            return getNarrowedType(type, predicate.type, assumeTrue, isTypeSubtypeOf);
+                        }
+                        if (containsMatchingReference(reference, predicateArgument)) {
+                            return declaredType;
+                        }
+                    }
+                }
+                else {
+                    var invokedExpression = ts.skipParentheses(callExpression.expression);
+                    if (invokedExpression.kind === 186 /* ElementAccessExpression */ || invokedExpression.kind === 185 /* PropertyAccessExpression */) {
+                        var accessExpression = invokedExpression;
+                        var possibleReference = ts.skipParentheses(accessExpression.expression);
+                        if (isMatchingReference(reference, possibleReference)) {
+                            return getNarrowedType(type, predicate.type, assumeTrue, isTypeSubtypeOf);
+                        }
+                        if (containsMatchingReference(reference, possibleReference)) {
+                            return declaredType;
+                        }
+                    }
+                }
+                return type;
+            }
+            // Narrow the given type based on the given expression having the assumed boolean value. The returned type
+            // will be a subtype or the same type as the argument.
+            function narrowType(type, expr, assumeTrue) {
+                switch (expr.kind) {
+                    case 71 /* Identifier */:
+                    case 99 /* ThisKeyword */:
+                    case 97 /* SuperKeyword */:
+                    case 185 /* PropertyAccessExpression */:
+                        return narrowTypeByTruthiness(type, expr, assumeTrue);
+                    case 187 /* CallExpression */:
+                        return narrowTypeByTypePredicate(type, expr, assumeTrue);
+                    case 191 /* ParenthesizedExpression */:
+                        return narrowType(type, expr.expression, assumeTrue);
+                    case 200 /* BinaryExpression */:
+                        return narrowTypeByBinaryExpression(type, expr, assumeTrue);
+                    case 198 /* PrefixUnaryExpression */:
+                        if (expr.operator === 51 /* ExclamationToken */) {
+                            return narrowType(type, expr.operand, !assumeTrue);
+                        }
+                        break;
+                }
+                return type;
+            }
+        }
+        function getTypeOfSymbolAtLocation(symbol, location) {
+            symbol = symbol.exportSymbol || symbol;
+            // If we have an identifier or a property access at the given location, if the location is
+            // an dotted name expression, and if the location is not an assignment target, obtain the type
+            // of the expression (which will reflect control flow analysis). If the expression indeed
+            // resolved to the given symbol, return the narrowed type.
+            if (location.kind === 71 /* Identifier */) {
+                if (ts.isRightSideOfQualifiedNameOrPropertyAccess(location)) {
+                    location = location.parent;
+                }
+                if (ts.isExpressionNode(location) && !ts.isAssignmentTarget(location)) {
+                    var type = getTypeOfExpression(location);
+                    if (getExportSymbolOfValueSymbolIfExported(getNodeLinks(location).resolvedSymbol) === symbol) {
+                        return type;
+                    }
+                }
+            }
+            // The location isn't a reference to the given symbol, meaning we're being asked
+            // a hypothetical question of what type the symbol would have if there was a reference
+            // to it at the given location. Since we have no control flow information for the
+            // hypothetical reference (control flow information is created and attached by the
+            // binder), we simply return the declared type of the symbol.
+            return getTypeOfSymbol(symbol);
+        }
+        function getControlFlowContainer(node) {
+            return ts.findAncestor(node.parent, function (node) {
+                return ts.isFunctionLike(node) && !ts.getImmediatelyInvokedFunctionExpression(node) ||
+                    node.kind === 240 /* ModuleBlock */ ||
+                    node.kind === 274 /* SourceFile */ ||
+                    node.kind === 152 /* PropertyDeclaration */;
+            });
+        }
+        // Check if a parameter is assigned anywhere within its declaring function.
+        function isParameterAssigned(symbol) {
+            var func = ts.getRootDeclaration(symbol.valueDeclaration).parent;
+            var links = getNodeLinks(func);
+            if (!(links.flags & 4194304 /* AssignmentsMarked */)) {
+                links.flags |= 4194304 /* AssignmentsMarked */;
+                if (!hasParentWithAssignmentsMarked(func)) {
+                    markParameterAssignments(func);
+                }
+            }
+            return symbol.isAssigned || false;
+        }
+        function hasParentWithAssignmentsMarked(node) {
+            return !!ts.findAncestor(node.parent, function (node) { return ts.isFunctionLike(node) && !!(getNodeLinks(node).flags & 4194304 /* AssignmentsMarked */); });
+        }
+        function markParameterAssignments(node) {
+            if (node.kind === 71 /* Identifier */) {
+                if (ts.isAssignmentTarget(node)) {
+                    var symbol = getResolvedSymbol(node);
+                    if (symbol.valueDeclaration && ts.getRootDeclaration(symbol.valueDeclaration).kind === 149 /* Parameter */) {
+                        symbol.isAssigned = true;
+                    }
+                }
+            }
+            else {
+                ts.forEachChild(node, markParameterAssignments);
+            }
+        }
+        function isConstVariable(symbol) {
+            return symbol.flags & 3 /* Variable */ && (getDeclarationNodeFlagsFromSymbol(symbol) & 2 /* Const */) !== 0 && getTypeOfSymbol(symbol) !== autoArrayType;
+        }
+        /** remove undefined from the annotated type of a parameter when there is an initializer (that doesn't include undefined) */
+        function removeOptionalityFromDeclaredType(declaredType, declaration) {
+            var annotationIncludesUndefined = strictNullChecks &&
+                declaration.kind === 149 /* Parameter */ &&
+                declaration.initializer &&
+                getFalsyFlags(declaredType) & 8192 /* Undefined */ &&
+                !(getFalsyFlags(checkExpression(declaration.initializer)) & 8192 /* Undefined */);
+            return annotationIncludesUndefined ? getTypeWithFacts(declaredType, 131072 /* NEUndefined */) : declaredType;
+        }
+        function isConstraintPosition(node) {
+            var parent = node.parent;
+            return parent.kind === 185 /* PropertyAccessExpression */ ||
+                parent.kind === 187 /* CallExpression */ && parent.expression === node ||
+                parent.kind === 186 /* ElementAccessExpression */ && parent.expression === node ||
+                parent.kind === 182 /* BindingElement */ && parent.name === node && !!parent.initializer;
+        }
+        function typeHasNullableConstraint(type) {
+            return type.flags & 14745600 /* InstantiableNonPrimitive */ && maybeTypeOfKind(getBaseConstraintOfType(type) || emptyObjectType, 24576 /* Nullable */);
+        }
+        function getConstraintForLocation(type, node) {
+            // When a node is the left hand expression of a property access, element access, or call expression,
+            // and the type of the node includes type variables with constraints that are nullable, we fetch the
+            // apparent type of the node *before* performing control flow analysis such that narrowings apply to
+            // the constraint type.
+            if (type && isConstraintPosition(node) && forEachType(type, typeHasNullableConstraint)) {
+                return mapType(getWidenedType(type), getBaseConstraintOrType);
+            }
+            return type;
+        }
+        function markAliasReferenced(symbol, location) {
+            if (isNonLocalAlias(symbol, /*excludes*/ 67216319 /* Value */) && !isInTypeQuery(location) && !isConstEnumOrConstEnumOnlyModule(resolveAlias(symbol))) {
+                markAliasSymbolAsReferenced(symbol);
+            }
+        }
+        function checkIdentifier(node) {
+            var symbol = getResolvedSymbol(node);
+            if (symbol === unknownSymbol) {
+                return errorType;
+            }
+            // As noted in ECMAScript 6 language spec, arrow functions never have an arguments objects.
+            // Although in down-level emit of arrow function, we emit it using function expression which means that
+            // arguments objects will be bound to the inner object; emitting arrow function natively in ES6, arguments objects
+            // will be bound to non-arrow function that contain this arrow function. This results in inconsistent behavior.
+            // To avoid that we will give an error to users if they use arguments objects in arrow function so that they
+            // can explicitly bound arguments objects
+            if (symbol === argumentsSymbol) {
+                var container = ts.getContainingFunction(node);
+                if (languageVersion < 2 /* ES2015 */) {
+                    if (container.kind === 193 /* ArrowFunction */) {
+                        error(node, ts.Diagnostics.The_arguments_object_cannot_be_referenced_in_an_arrow_function_in_ES3_and_ES5_Consider_using_a_standard_function_expression);
+                    }
+                    else if (ts.hasModifier(container, 256 /* Async */)) {
+                        error(node, ts.Diagnostics.The_arguments_object_cannot_be_referenced_in_an_async_function_or_method_in_ES3_and_ES5_Consider_using_a_standard_function_or_method);
+                    }
+                }
+                getNodeLinks(container).flags |= 8192 /* CaptureArguments */;
+                return getTypeOfSymbol(symbol);
+            }
+            // We should only mark aliases as referenced if there isn't a local value declaration
+            // for the symbol. Also, don't mark any property access expression LHS - checkPropertyAccessExpression will handle that
+            if (!(node.parent && ts.isPropertyAccessExpression(node.parent) && node.parent.expression === node)) {
+                markAliasReferenced(symbol, node);
+            }
+            var localOrExportSymbol = getExportSymbolOfValueSymbolIfExported(symbol);
+            var declaration = localOrExportSymbol.valueDeclaration;
+            if (localOrExportSymbol.flags & 32 /* Class */) {
+                // Due to the emit for class decorators, any reference to the class from inside of the class body
+                // must instead be rewritten to point to a temporary variable to avoid issues with the double-bind
+                // behavior of class names in ES6.
+                if (declaration.kind === 235 /* ClassDeclaration */
+                    && ts.nodeIsDecorated(declaration)) {
+                    var container = ts.getContainingClass(node);
+                    while (container !== undefined) {
+                        if (container === declaration && container.name !== node) {
+                            getNodeLinks(declaration).flags |= 8388608 /* ClassWithConstructorReference */;
+                            getNodeLinks(node).flags |= 16777216 /* ConstructorReferenceInClass */;
+                            break;
+                        }
+                        container = ts.getContainingClass(container);
+                    }
+                }
+                else if (declaration.kind === 205 /* ClassExpression */) {
+                    // When we emit a class expression with static members that contain a reference
+                    // to the constructor in the initializer, we will need to substitute that
+                    // binding with an alias as the class name is not in scope.
+                    var container = ts.getThisContainer(node, /*includeArrowFunctions*/ false);
+                    while (container.kind !== 274 /* SourceFile */) {
+                        if (container.parent === declaration) {
+                            if (container.kind === 152 /* PropertyDeclaration */ && ts.hasModifier(container, 32 /* Static */)) {
+                                getNodeLinks(declaration).flags |= 8388608 /* ClassWithConstructorReference */;
+                                getNodeLinks(node).flags |= 16777216 /* ConstructorReferenceInClass */;
+                            }
+                            break;
+                        }
+                        container = ts.getThisContainer(container, /*includeArrowFunctions*/ false);
+                    }
+                }
+            }
+            checkNestedBlockScopedBinding(node, symbol);
+            var type = getConstraintForLocation(getTypeOfSymbol(localOrExportSymbol), node);
+            var assignmentKind = ts.getAssignmentTargetKind(node);
+            if (assignmentKind) {
+                if (!(localOrExportSymbol.flags & 3 /* Variable */) &&
+                    !(ts.isInJavaScriptFile(node) && localOrExportSymbol.flags & 512 /* ValueModule */)) {
+                    error(node, ts.Diagnostics.Cannot_assign_to_0_because_it_is_not_a_variable, symbolToString(symbol));
+                    return errorType;
+                }
+                if (isReadonlySymbol(localOrExportSymbol)) {
+                    error(node, ts.Diagnostics.Cannot_assign_to_0_because_it_is_a_constant_or_a_read_only_property, symbolToString(symbol));
+                    return errorType;
+                }
+            }
+            var isAlias = localOrExportSymbol.flags & 2097152 /* Alias */;
+            // We only narrow variables and parameters occurring in a non-assignment position. For all other
+            // entities we simply return the declared type.
+            if (localOrExportSymbol.flags & 3 /* Variable */) {
+                if (assignmentKind === 1 /* Definite */) {
+                    return type;
+                }
+            }
+            else if (isAlias) {
+                declaration = ts.find(symbol.declarations, isSomeImportDeclaration);
+            }
+            else {
+                return type;
+            }
+            if (!declaration) {
+                return type;
+            }
+            // The declaration container is the innermost function that encloses the declaration of the variable
+            // or parameter. The flow container is the innermost function starting with which we analyze the control
+            // flow graph to determine the control flow based type.
+            var isParameter = ts.getRootDeclaration(declaration).kind === 149 /* Parameter */;
+            var declarationContainer = getControlFlowContainer(declaration);
+            var flowContainer = getControlFlowContainer(node);
+            var isOuterVariable = flowContainer !== declarationContainer;
+            var isSpreadDestructuringAsignmentTarget = node.parent && node.parent.parent && ts.isSpreadAssignment(node.parent) && isDestructuringAssignmentTarget(node.parent.parent);
+            // When the control flow originates in a function expression or arrow function and we are referencing
+            // a const variable or parameter from an outer function, we extend the origin of the control flow
+            // analysis to include the immediately enclosing function.
+            while (flowContainer !== declarationContainer && (flowContainer.kind === 192 /* FunctionExpression */ ||
+                flowContainer.kind === 193 /* ArrowFunction */ || ts.isObjectLiteralOrClassExpressionMethod(flowContainer)) &&
+                (isConstVariable(localOrExportSymbol) || isParameter && !isParameterAssigned(localOrExportSymbol))) {
+                flowContainer = getControlFlowContainer(flowContainer);
+            }
+            // We only look for uninitialized variables in strict null checking mode, and only when we can analyze
+            // the entire control flow graph from the variable's declaration (i.e. when the flow container and
+            // declaration container are the same).
+            var assumeInitialized = isParameter || isAlias || isOuterVariable || isSpreadDestructuringAsignmentTarget ||
+                type !== autoType && type !== autoArrayType && (!strictNullChecks || (type.flags & 3 /* AnyOrUnknown */) !== 0 ||
+                    isInTypeQuery(node) || node.parent.kind === 252 /* ExportSpecifier */) ||
+                node.parent.kind === 209 /* NonNullExpression */ ||
+                declaration.kind === 232 /* VariableDeclaration */ && declaration.exclamationToken ||
+                declaration.flags & 4194304 /* Ambient */;
+            var initialType = assumeInitialized ? (isParameter ? removeOptionalityFromDeclaredType(type, declaration) : type) :
+                type === autoType || type === autoArrayType ? undefinedType :
+                    getOptionalType(type);
+            var flowType = getFlowTypeOfReference(node, type, initialType, flowContainer, !assumeInitialized);
+            // A variable is considered uninitialized when it is possible to analyze the entire control flow graph
+            // from declaration to use, and when the variable's declared type doesn't include undefined but the
+            // control flow based type does include undefined.
+            if (type === autoType || type === autoArrayType) {
+                if (flowType === autoType || flowType === autoArrayType) {
+                    if (noImplicitAny) {
+                        error(ts.getNameOfDeclaration(declaration), ts.Diagnostics.Variable_0_implicitly_has_type_1_in_some_locations_where_its_type_cannot_be_determined, symbolToString(symbol), typeToString(flowType));
+                        error(node, ts.Diagnostics.Variable_0_implicitly_has_an_1_type, symbolToString(symbol), typeToString(flowType));
+                    }
+                    return convertAutoToAny(flowType);
+                }
+            }
+            else if (!assumeInitialized && !(getFalsyFlags(type) & 8192 /* Undefined */) && getFalsyFlags(flowType) & 8192 /* Undefined */) {
+                error(node, ts.Diagnostics.Variable_0_is_used_before_being_assigned, symbolToString(symbol));
+                // Return the declared type to reduce follow-on errors
+                return type;
+            }
+            return assignmentKind ? getBaseTypeOfLiteralType(flowType) : flowType;
+        }
+        function isInsideFunction(node, threshold) {
+            return !!ts.findAncestor(node, function (n) { return n === threshold ? "quit" : ts.isFunctionLike(n); });
+        }
+        function checkNestedBlockScopedBinding(node, symbol) {
+            if (languageVersion >= 2 /* ES2015 */ ||
+                (symbol.flags & (2 /* BlockScopedVariable */ | 32 /* Class */)) === 0 ||
+                symbol.valueDeclaration.parent.kind === 269 /* CatchClause */) {
+                return;
+            }
+            // 1. walk from the use site up to the declaration and check
+            // if there is anything function like between declaration and use-site (is binding/class is captured in function).
+            // 2. walk from the declaration up to the boundary of lexical environment and check
+            // if there is an iteration statement in between declaration and boundary (is binding/class declared inside iteration statement)
+            var container = ts.getEnclosingBlockScopeContainer(symbol.valueDeclaration);
+            var usedInFunction = isInsideFunction(node.parent, container);
+            var current = container;
+            var containedInIterationStatement = false;
+            while (current && !ts.nodeStartsNewLexicalEnvironment(current)) {
+                if (ts.isIterationStatement(current, /*lookInLabeledStatements*/ false)) {
+                    containedInIterationStatement = true;
+                    break;
+                }
+                current = current.parent;
+            }
+            if (containedInIterationStatement) {
+                if (usedInFunction) {
+                    // mark iteration statement as containing block-scoped binding captured in some function
+                    getNodeLinks(current).flags |= 65536 /* LoopWithCapturedBlockScopedBinding */;
+                }
+                // mark variables that are declared in loop initializer and reassigned inside the body of ForStatement.
+                // if body of ForStatement will be converted to function then we'll need a extra machinery to propagate reassigned values back.
+                if (container.kind === 220 /* ForStatement */ &&
+                    ts.getAncestor(symbol.valueDeclaration, 233 /* VariableDeclarationList */).parent === container &&
+                    isAssignedInBodyOfForStatement(node, container)) {
+                    getNodeLinks(symbol.valueDeclaration).flags |= 2097152 /* NeedsLoopOutParameter */;
+                }
+                // set 'declared inside loop' bit on the block-scoped binding
+                getNodeLinks(symbol.valueDeclaration).flags |= 262144 /* BlockScopedBindingInLoop */;
+            }
+            if (usedInFunction) {
+                getNodeLinks(symbol.valueDeclaration).flags |= 131072 /* CapturedBlockScopedBinding */;
+            }
+        }
+        function isAssignedInBodyOfForStatement(node, container) {
+            // skip parenthesized nodes
+            var current = node;
+            while (current.parent.kind === 191 /* ParenthesizedExpression */) {
+                current = current.parent;
+            }
+            // check if node is used as LHS in some assignment expression
+            var isAssigned = false;
+            if (ts.isAssignmentTarget(current)) {
+                isAssigned = true;
+            }
+            else if ((current.parent.kind === 198 /* PrefixUnaryExpression */ || current.parent.kind === 199 /* PostfixUnaryExpression */)) {
+                var expr = current.parent;
+                isAssigned = expr.operator === 43 /* PlusPlusToken */ || expr.operator === 44 /* MinusMinusToken */;
+            }
+            if (!isAssigned) {
+                return false;
+            }
+            // at this point we know that node is the target of assignment
+            // now check that modification happens inside the statement part of the ForStatement
+            return !!ts.findAncestor(current, function (n) { return n === container ? "quit" : n === container.statement; });
+        }
+        function captureLexicalThis(node, container) {
+            getNodeLinks(node).flags |= 2 /* LexicalThis */;
+            if (container.kind === 152 /* PropertyDeclaration */ || container.kind === 155 /* Constructor */) {
+                var classNode = container.parent;
+                getNodeLinks(classNode).flags |= 4 /* CaptureThis */;
+            }
+            else {
+                getNodeLinks(container).flags |= 4 /* CaptureThis */;
+            }
+        }
+        function findFirstSuperCall(n) {
+            if (ts.isSuperCall(n)) {
+                return n;
+            }
+            else if (ts.isFunctionLike(n)) {
+                return undefined;
+            }
+            return ts.forEachChild(n, findFirstSuperCall);
+        }
+        /**
+         * Return a cached result if super-statement is already found.
+         * Otherwise, find a super statement in a given constructor function and cache the result in the node-links of the constructor
+         *
+         * @param constructor constructor-function to look for super statement
+         */
+        function getSuperCallInConstructor(constructor) {
+            var links = getNodeLinks(constructor);
+            // Only trying to find super-call if we haven't yet tried to find one.  Once we try, we will record the result
+            if (links.hasSuperCall === undefined) {
+                links.superCall = findFirstSuperCall(constructor.body);
+                links.hasSuperCall = links.superCall ? true : false;
+            }
+            return links.superCall;
+        }
+        /**
+         * Check if the given class-declaration extends null then return true.
+         * Otherwise, return false
+         * @param classDecl a class declaration to check if it extends null
+         */
+        function classDeclarationExtendsNull(classDecl) {
+            var classSymbol = getSymbolOfNode(classDecl);
+            var classInstanceType = getDeclaredTypeOfSymbol(classSymbol);
+            var baseConstructorType = getBaseConstructorTypeOfClass(classInstanceType);
+            return baseConstructorType === nullWideningType;
+        }
+        function checkThisBeforeSuper(node, container, diagnosticMessage) {
+            var containingClassDecl = container.parent;
+            var baseTypeNode = ts.getClassExtendsHeritageClauseElement(containingClassDecl);
+            // If a containing class does not have extends clause or the class extends null
+            // skip checking whether super statement is called before "this" accessing.
+            if (baseTypeNode && !classDeclarationExtendsNull(containingClassDecl)) {
+                var superCall = getSuperCallInConstructor(container);
+                // We should give an error in the following cases:
+                //      - No super-call
+                //      - "this" is accessing before super-call.
+                //          i.e super(this)
+                //              this.x; super();
+                // We want to make sure that super-call is done before accessing "this" so that
+                // "this" is not accessed as a parameter of the super-call.
+                if (!superCall || superCall.end > node.pos) {
+                    // In ES6, super inside constructor of class-declaration has to precede "this" accessing
+                    error(node, diagnosticMessage);
+                }
+            }
+        }
+        function checkThisExpression(node) {
+            // Stop at the first arrow function so that we can
+            // tell whether 'this' needs to be captured.
+            var container = ts.getThisContainer(node, /* includeArrowFunctions */ true);
+            var needToCaptureLexicalThis = false;
+            if (container.kind === 155 /* Constructor */) {
+                checkThisBeforeSuper(node, container, ts.Diagnostics.super_must_be_called_before_accessing_this_in_the_constructor_of_a_derived_class);
+            }
+            // Now skip arrow functions to get the "real" owner of 'this'.
+            if (container.kind === 193 /* ArrowFunction */) {
+                container = ts.getThisContainer(container, /* includeArrowFunctions */ false);
+                // When targeting es6, arrow function lexically bind "this" so we do not need to do the work of binding "this" in emitted code
+                needToCaptureLexicalThis = (languageVersion < 2 /* ES2015 */);
+            }
+            switch (container.kind) {
+                case 239 /* ModuleDeclaration */:
+                    error(node, ts.Diagnostics.this_cannot_be_referenced_in_a_module_or_namespace_body);
+                    // do not return here so in case if lexical this is captured - it will be reflected in flags on NodeLinks
+                    break;
+                case 238 /* EnumDeclaration */:
+                    error(node, ts.Diagnostics.this_cannot_be_referenced_in_current_location);
+                    // do not return here so in case if lexical this is captured - it will be reflected in flags on NodeLinks
+                    break;
+                case 155 /* Constructor */:
+                    if (isInConstructorArgumentInitializer(node, container)) {
+                        error(node, ts.Diagnostics.this_cannot_be_referenced_in_constructor_arguments);
+                        // do not return here so in case if lexical this is captured - it will be reflected in flags on NodeLinks
+                    }
+                    break;
+                case 152 /* PropertyDeclaration */:
+                case 151 /* PropertySignature */:
+                    if (ts.hasModifier(container, 32 /* Static */)) {
+                        error(node, ts.Diagnostics.this_cannot_be_referenced_in_a_static_property_initializer);
+                        // do not return here so in case if lexical this is captured - it will be reflected in flags on NodeLinks
+                    }
+                    break;
+                case 147 /* ComputedPropertyName */:
+                    error(node, ts.Diagnostics.this_cannot_be_referenced_in_a_computed_property_name);
+                    break;
+            }
+            if (needToCaptureLexicalThis) {
+                captureLexicalThis(node, container);
+            }
+            var type = tryGetThisTypeAt(node, container);
+            if (!type && noImplicitThis) {
+                // With noImplicitThis, functions may not reference 'this' if it has type 'any'
+                error(node, ts.Diagnostics.this_implicitly_has_type_any_because_it_does_not_have_a_type_annotation);
+            }
+            return type || anyType;
+        }
+        function tryGetThisTypeAt(node, container) {
+            if (container === void 0) { container = ts.getThisContainer(node, /*includeArrowFunctions*/ false); }
+            if (ts.isFunctionLike(container) &&
+                (!isInParameterInitializerBeforeContainingFunction(node) || ts.getThisParameter(container))) {
+                // Note: a parameter initializer should refer to class-this unless function-this is explicitly annotated.
+                // If this is a function in a JS file, it might be a class method. Check if it's the RHS
+                // of a x.prototype.y = function [name]() { .... }
+                if (container.kind === 192 /* FunctionExpression */ &&
+                    container.parent.kind === 200 /* BinaryExpression */ &&
+                    ts.getSpecialPropertyAssignmentKind(container.parent) === 3 /* PrototypeProperty */) {
+                    // Get the 'x' of 'x.prototype.y = f' (here, 'f' is 'container')
+                    var className = container.parent // x.prototype.y = f
+                        .left // x.prototype.y
+                        .expression // x.prototype
+                        .expression; // x
+                    var classSymbol = checkExpression(className).symbol;
+                    if (classSymbol && classSymbol.members && (classSymbol.flags & 16 /* Function */)) {
+                        return getFlowTypeOfReference(node, getInferredClassType(classSymbol));
+                    }
+                }
+                var thisType = getThisTypeOfDeclaration(container) || getContextualThisParameterType(container);
+                if (thisType) {
+                    return getFlowTypeOfReference(node, thisType);
+                }
+            }
+            if (ts.isClassLike(container.parent)) {
+                var symbol = getSymbolOfNode(container.parent);
+                var type = ts.hasModifier(container, 32 /* Static */) ? getTypeOfSymbol(symbol) : getDeclaredTypeOfSymbol(symbol).thisType;
+                return getFlowTypeOfReference(node, type);
+            }
+            if (ts.isInJavaScriptFile(node)) {
+                var type = getTypeForThisExpressionFromJSDoc(container);
+                if (type && type !== errorType) {
+                    return getFlowTypeOfReference(node, type);
+                }
+            }
+        }
+        function getTypeForThisExpressionFromJSDoc(node) {
+            var jsdocType = ts.getJSDocType(node);
+            if (jsdocType && jsdocType.kind === 284 /* JSDocFunctionType */) {
+                var jsDocFunctionType = jsdocType;
+                if (jsDocFunctionType.parameters.length > 0 &&
+                    jsDocFunctionType.parameters[0].name &&
+                    jsDocFunctionType.parameters[0].name.escapedText === "this") {
+                    return getTypeFromTypeNode(jsDocFunctionType.parameters[0].type);
+                }
+            }
+        }
+        function isInConstructorArgumentInitializer(node, constructorDecl) {
+            return !!ts.findAncestor(node, function (n) { return n === constructorDecl ? "quit" : n.kind === 149 /* Parameter */; });
+        }
+        function checkSuperExpression(node) {
+            var isCallExpression = node.parent.kind === 187 /* CallExpression */ && node.parent.expression === node;
+            var container = ts.getSuperContainer(node, /*stopOnFunctions*/ true);
+            var needToCaptureLexicalThis = false;
+            // adjust the container reference in case if super is used inside arrow functions with arbitrarily deep nesting
+            if (!isCallExpression) {
+                while (container && container.kind === 193 /* ArrowFunction */) {
+                    container = ts.getSuperContainer(container, /*stopOnFunctions*/ true);
+                    needToCaptureLexicalThis = languageVersion < 2 /* ES2015 */;
+                }
+            }
+            var canUseSuperExpression = isLegalUsageOfSuperExpression(container);
+            var nodeCheckFlag = 0;
+            if (!canUseSuperExpression) {
+                // issue more specific error if super is used in computed property name
+                // class A { foo() { return "1" }}
+                // class B {
+                //     [super.foo()]() {}
+                // }
+                var current = ts.findAncestor(node, function (n) { return n === container ? "quit" : n.kind === 147 /* ComputedPropertyName */; });
+                if (current && current.kind === 147 /* ComputedPropertyName */) {
+                    error(node, ts.Diagnostics.super_cannot_be_referenced_in_a_computed_property_name);
+                }
+                else if (isCallExpression) {
+                    error(node, ts.Diagnostics.Super_calls_are_not_permitted_outside_constructors_or_in_nested_functions_inside_constructors);
+                }
+                else if (!container || !container.parent || !(ts.isClassLike(container.parent) || container.parent.kind === 184 /* ObjectLiteralExpression */)) {
+                    error(node, ts.Diagnostics.super_can_only_be_referenced_in_members_of_derived_classes_or_object_literal_expressions);
+                }
+                else {
+                    error(node, ts.Diagnostics.super_property_access_is_permitted_only_in_a_constructor_member_function_or_member_accessor_of_a_derived_class);
+                }
+                return errorType;
+            }
+            if (!isCallExpression && container.kind === 155 /* Constructor */) {
+                checkThisBeforeSuper(node, container, ts.Diagnostics.super_must_be_called_before_accessing_a_property_of_super_in_the_constructor_of_a_derived_class);
+            }
+            if (ts.hasModifier(container, 32 /* Static */) || isCallExpression) {
+                nodeCheckFlag = 512 /* SuperStatic */;
+            }
+            else {
+                nodeCheckFlag = 256 /* SuperInstance */;
+            }
+            getNodeLinks(node).flags |= nodeCheckFlag;
+            // Due to how we emit async functions, we need to specialize the emit for an async method that contains a `super` reference.
+            // This is due to the fact that we emit the body of an async function inside of a generator function. As generator
+            // functions cannot reference `super`, we emit a helper inside of the method body, but outside of the generator. This helper
+            // uses an arrow function, which is permitted to reference `super`.
+            //
+            // There are two primary ways we can access `super` from within an async method. The first is getting the value of a property
+            // or indexed access on super, either as part of a right-hand-side expression or call expression. The second is when setting the value
+            // of a property or indexed access, either as part of an assignment expression or destructuring assignment.
+            //
+            // The simplest case is reading a value, in which case we will emit something like the following:
+            //
+            //  // ts
+            //  ...
+            //  async asyncMethod() {
+            //    let x = await super.asyncMethod();
+            //    return x;
+            //  }
+            //  ...
+            //
+            //  // js
+            //  ...
+            //  asyncMethod() {
+            //      const _super = name => super[name];
+            //      return __awaiter(this, arguments, Promise, function *() {
+            //          let x = yield _super("asyncMethod").call(this);
+            //          return x;
+            //      });
+            //  }
+            //  ...
+            //
+            // The more complex case is when we wish to assign a value, especially as part of a destructuring assignment. As both cases
+            // are legal in ES6, but also likely less frequent, we emit the same more complex helper for both scenarios:
+            //
+            //  // ts
+            //  ...
+            //  async asyncMethod(ar: Promise<any[]>) {
+            //      [super.a, super.b] = await ar;
+            //  }
+            //  ...
+            //
+            //  // js
+            //  ...
+            //  asyncMethod(ar) {
+            //      const _super = (function (geti, seti) {
+            //          const cache = Object.create(null);
+            //          return name => cache[name] || (cache[name] = { get value() { return geti(name); }, set value(v) { seti(name, v); } });
+            //      })(name => super[name], (name, value) => super[name] = value);
+            //      return __awaiter(this, arguments, Promise, function *() {
+            //          [_super("a").value, _super("b").value] = yield ar;
+            //      });
+            //  }
+            //  ...
+            //
+            // This helper creates an object with a "value" property that wraps the `super` property or indexed access for both get and set.
+            // This is required for destructuring assignments, as a call expression cannot be used as the target of a destructuring assignment
+            // while a property access can.
+            if (container.kind === 154 /* MethodDeclaration */ && ts.hasModifier(container, 256 /* Async */)) {
+                if (ts.isSuperProperty(node.parent) && ts.isAssignmentTarget(node.parent)) {
+                    getNodeLinks(container).flags |= 4096 /* AsyncMethodWithSuperBinding */;
+                }
+                else {
+                    getNodeLinks(container).flags |= 2048 /* AsyncMethodWithSuper */;
+                }
+            }
+            if (needToCaptureLexicalThis) {
+                // call expressions are allowed only in constructors so they should always capture correct 'this'
+                // super property access expressions can also appear in arrow functions -
+                // in this case they should also use correct lexical this
+                captureLexicalThis(node.parent, container);
+            }
+            if (container.parent.kind === 184 /* ObjectLiteralExpression */) {
+                if (languageVersion < 2 /* ES2015 */) {
+                    error(node, ts.Diagnostics.super_is_only_allowed_in_members_of_object_literal_expressions_when_option_target_is_ES2015_or_higher);
+                    return errorType;
+                }
+                else {
+                    // for object literal assume that type of 'super' is 'any'
+                    return anyType;
+                }
+            }
+            // at this point the only legal case for parent is ClassLikeDeclaration
+            var classLikeDeclaration = container.parent;
+            if (!ts.getClassExtendsHeritageClauseElement(classLikeDeclaration)) {
+                error(node, ts.Diagnostics.super_can_only_be_referenced_in_a_derived_class);
+                return errorType;
+            }
+            var classType = getDeclaredTypeOfSymbol(getSymbolOfNode(classLikeDeclaration));
+            var baseClassType = classType && getBaseTypes(classType)[0];
+            if (!baseClassType) {
+                return errorType;
+            }
+            if (container.kind === 155 /* Constructor */ && isInConstructorArgumentInitializer(node, container)) {
+                // issue custom error message for super property access in constructor arguments (to be aligned with old compiler)
+                error(node, ts.Diagnostics.super_cannot_be_referenced_in_constructor_arguments);
+                return errorType;
+            }
+            return nodeCheckFlag === 512 /* SuperStatic */
+                ? getBaseConstructorTypeOfClass(classType)
+                : getTypeWithThisArgument(baseClassType, classType.thisType);
+            function isLegalUsageOfSuperExpression(container) {
+                if (!container) {
+                    return false;
+                }
+                if (isCallExpression) {
+                    // TS 1.0 SPEC (April 2014): 4.8.1
+                    // Super calls are only permitted in constructors of derived classes
+                    return container.kind === 155 /* Constructor */;
+                }
+                else {
+                    // TS 1.0 SPEC (April 2014)
+                    // 'super' property access is allowed
+                    // - In a constructor, instance member function, instance member accessor, or instance member variable initializer where this references a derived class instance
+                    // - In a static member function or static member accessor
+                    // topmost container must be something that is directly nested in the class declaration\object literal expression
+                    if (ts.isClassLike(container.parent) || container.parent.kind === 184 /* ObjectLiteralExpression */) {
+                        if (ts.hasModifier(container, 32 /* Static */)) {
+                            return container.kind === 154 /* MethodDeclaration */ ||
+                                container.kind === 153 /* MethodSignature */ ||
+                                container.kind === 156 /* GetAccessor */ ||
+                                container.kind === 157 /* SetAccessor */;
+                        }
+                        else {
+                            return container.kind === 154 /* MethodDeclaration */ ||
+                                container.kind === 153 /* MethodSignature */ ||
+                                container.kind === 156 /* GetAccessor */ ||
+                                container.kind === 157 /* SetAccessor */ ||
+                                container.kind === 152 /* PropertyDeclaration */ ||
+                                container.kind === 151 /* PropertySignature */ ||
+                                container.kind === 155 /* Constructor */;
+                        }
+                    }
+                }
+                return false;
+            }
+        }
+        function getContainingObjectLiteral(func) {
+            return (func.kind === 154 /* MethodDeclaration */ ||
+                func.kind === 156 /* GetAccessor */ ||
+                func.kind === 157 /* SetAccessor */) && func.parent.kind === 184 /* ObjectLiteralExpression */ ? func.parent :
+                func.kind === 192 /* FunctionExpression */ && func.parent.kind === 270 /* PropertyAssignment */ ? func.parent.parent :
+                    undefined;
+        }
+        function getThisTypeArgument(type) {
+            return ts.getObjectFlags(type) & 4 /* Reference */ && type.target === globalThisType ? type.typeArguments[0] : undefined;
+        }
+        function getThisTypeFromContextualType(type) {
+            return mapType(type, function (t) {
+                return t.flags & 524288 /* Intersection */ ? ts.forEach(t.types, getThisTypeArgument) : getThisTypeArgument(t);
+            });
+        }
+        function getContextualThisParameterType(func) {
+            if (func.kind === 193 /* ArrowFunction */) {
+                return undefined;
+            }
+            if (isContextSensitiveFunctionOrObjectLiteralMethod(func)) {
+                var contextualSignature = getContextualSignature(func);
+                if (contextualSignature) {
+                    var thisParameter = contextualSignature.thisParameter;
+                    if (thisParameter) {
+                        return getTypeOfSymbol(thisParameter);
+                    }
+                }
+            }
+            var inJs = ts.isInJavaScriptFile(func);
+            if (noImplicitThis || inJs) {
+                var containingLiteral = getContainingObjectLiteral(func);
+                if (containingLiteral) {
+                    // We have an object literal method. Check if the containing object literal has a contextual type
+                    // that includes a ThisType<T>. If so, T is the contextual type for 'this'. We continue looking in
+                    // any directly enclosing object literals.
+                    var contextualType = getApparentTypeOfContextualType(containingLiteral);
+                    var literal = containingLiteral;
+                    var type = contextualType;
+                    while (type) {
+                        var thisType = getThisTypeFromContextualType(type);
+                        if (thisType) {
+                            return instantiateType(thisType, getContextualMapper(containingLiteral));
+                        }
+                        if (literal.parent.kind !== 270 /* PropertyAssignment */) {
+                            break;
+                        }
+                        literal = literal.parent.parent;
+                        type = getApparentTypeOfContextualType(literal);
+                    }
+                    // There was no contextual ThisType<T> for the containing object literal, so the contextual type
+                    // for 'this' is the non-null form of the contextual type for the containing object literal or
+                    // the type of the object literal itself.
+                    return contextualType ? getNonNullableType(contextualType) : checkExpressionCached(containingLiteral);
+                }
+                // In an assignment of the form 'obj.xxx = function(...)' or 'obj[xxx] = function(...)', the
+                // contextual type for 'this' is 'obj'.
+                var parent = func.parent;
+                if (parent.kind === 200 /* BinaryExpression */ && parent.operatorToken.kind === 58 /* EqualsToken */) {
+                    var target = parent.left;
+                    if (target.kind === 185 /* PropertyAccessExpression */ || target.kind === 186 /* ElementAccessExpression */) {
+                        var expression = target.expression;
+                        // Don't contextually type `this` as `exports` in `exports.Point = function(x, y) { this.x = x; this.y = y; }`
+                        if (inJs && ts.isIdentifier(expression)) {
+                            var sourceFile = ts.getSourceFileOfNode(parent);
+                            if (sourceFile.commonJsModuleIndicator && getResolvedSymbol(expression) === sourceFile.symbol) {
+                                return undefined;
+                            }
+                        }
+                        return checkExpressionCached(expression);
+                    }
+                }
+            }
+            return undefined;
+        }
+        // Return contextual type of parameter or undefined if no contextual type is available
+        function getContextuallyTypedParameterType(parameter) {
+            var func = parameter.parent;
+            if (!isContextSensitiveFunctionOrObjectLiteralMethod(func)) {
+                return undefined;
+            }
+            var iife = ts.getImmediatelyInvokedFunctionExpression(func);
+            if (iife && iife.arguments) {
+                var indexOfParameter = func.parameters.indexOf(parameter);
+                if (parameter.dotDotDotToken) {
+                    var restTypes = [];
+                    for (var i = indexOfParameter; i < iife.arguments.length; i++) {
+                        restTypes.push(getWidenedLiteralType(checkExpression(iife.arguments[i])));
+                    }
+                    return restTypes.length ? createArrayType(getUnionType(restTypes)) : undefined;
+                }
+                var links = getNodeLinks(iife);
+                var cached = links.resolvedSignature;
+                links.resolvedSignature = anySignature;
+                var type = indexOfParameter < iife.arguments.length ?
+                    getWidenedLiteralType(checkExpression(iife.arguments[indexOfParameter])) :
+                    parameter.initializer ? undefined : undefinedWideningType;
+                links.resolvedSignature = cached;
+                return type;
+            }
+            var contextualSignature = getContextualSignature(func);
+            if (contextualSignature) {
+                var funcHasRestParameters = ts.hasRestParameter(func);
+                var len = func.parameters.length - (funcHasRestParameters ? 1 : 0);
+                var indexOfParameter = func.parameters.indexOf(parameter);
+                if (ts.getThisParameter(func) !== undefined && !contextualSignature.thisParameter) {
+                    ts.Debug.assert(indexOfParameter !== 0); // Otherwise we should not have called `getContextuallyTypedParameterType`.
+                    indexOfParameter -= 1;
+                }
+                if (indexOfParameter < len) {
+                    return getTypeAtPosition(contextualSignature, indexOfParameter);
+                }
+                // If last parameter is contextually rest parameter get its type
+                if (funcHasRestParameters &&
+                    indexOfParameter === (func.parameters.length - 1) &&
+                    isRestParameterIndex(contextualSignature, func.parameters.length - 1)) {
+                    return getTypeOfSymbol(ts.last(contextualSignature.parameters));
+                }
+            }
+        }
+        // In a variable, parameter or property declaration with a type annotation,
+        //   the contextual type of an initializer expression is the type of the variable, parameter or property.
+        // Otherwise, in a parameter declaration of a contextually typed function expression,
+        //   the contextual type of an initializer expression is the contextual type of the parameter.
+        // Otherwise, in a variable or parameter declaration with a binding pattern name,
+        //   the contextual type of an initializer expression is the type implied by the binding pattern.
+        // Otherwise, in a binding pattern inside a variable or parameter declaration,
+        //   the contextual type of an initializer expression is the type annotation of the containing declaration, if present.
+        function getContextualTypeForInitializerExpression(node) {
+            var declaration = node.parent;
+            if (ts.hasInitializer(declaration) && node === declaration.initializer) {
+                var typeNode = ts.getEffectiveTypeAnnotationNode(declaration);
+                if (typeNode) {
+                    return getTypeFromTypeNode(typeNode);
+                }
+                if (declaration.kind === 149 /* Parameter */) {
+                    var type = getContextuallyTypedParameterType(declaration);
+                    if (type) {
+                        return type;
+                    }
+                }
+                if (ts.isBindingPattern(declaration.name)) {
+                    return getTypeFromBindingPattern(declaration.name, /*includePatternInType*/ true, /*reportErrors*/ false);
+                }
+                if (ts.isBindingPattern(declaration.parent)) {
+                    var parentDeclaration = declaration.parent.parent;
+                    var name = declaration.propertyName || declaration.name;
+                    if (parentDeclaration.kind !== 182 /* BindingElement */) {
+                        var parentTypeNode = ts.getEffectiveTypeAnnotationNode(parentDeclaration);
+                        if (parentTypeNode && !ts.isBindingPattern(name)) {
+                            var text = ts.getTextOfPropertyName(name);
+                            if (text) {
+                                return getTypeOfPropertyOfType(getTypeFromTypeNode(parentTypeNode), text);
+                            }
+                        }
+                    }
+                }
+            }
+            return undefined;
+        }
+        function getContextualTypeForReturnExpression(node) {
+            var func = ts.getContainingFunction(node);
+            if (func) {
+                var functionFlags = ts.getFunctionFlags(func);
+                if (functionFlags & 1 /* Generator */) { // AsyncGenerator function or Generator function
+                    return undefined;
+                }
+                var contextualReturnType = getContextualReturnType(func);
+                return functionFlags & 2 /* Async */
+                    ? contextualReturnType && getAwaitedTypeOfPromise(contextualReturnType) // Async function
+                    : contextualReturnType; // Regular function
+            }
+            return undefined;
+        }
+        function getContextualTypeForYieldOperand(node) {
+            var func = ts.getContainingFunction(node);
+            if (func) {
+                var functionFlags = ts.getFunctionFlags(func);
+                var contextualReturnType = getContextualReturnType(func);
+                if (contextualReturnType) {
+                    return node.asteriskToken
+                        ? contextualReturnType
+                        : getIteratedTypeOfGenerator(contextualReturnType, (functionFlags & 2 /* Async */) !== 0);
+                }
+            }
+            return undefined;
+        }
+        function isInParameterInitializerBeforeContainingFunction(node) {
+            var inBindingInitializer = false;
+            while (node.parent && !ts.isFunctionLike(node.parent)) {
+                if (ts.isParameter(node.parent) && (inBindingInitializer || node.parent.initializer === node)) {
+                    return true;
+                }
+                if (ts.isBindingElement(node.parent) && node.parent.initializer === node) {
+                    inBindingInitializer = true;
+                }
+                node = node.parent;
+            }
+            return false;
+        }
+        function getContextualReturnType(functionDecl) {
+            // If the containing function has a return type annotation, is a constructor, or is a get accessor whose
+            // corresponding set accessor has a type annotation, return statements in the function are contextually typed
+            if (functionDecl.kind === 155 /* Constructor */ ||
+                ts.getEffectiveReturnTypeNode(functionDecl) ||
+                isGetAccessorWithAnnotatedSetAccessor(functionDecl)) {
+                return getReturnTypeOfSignature(getSignatureFromDeclaration(functionDecl));
+            }
+            // Otherwise, if the containing function is contextually typed by a function type with exactly one call signature
+            // and that call signature is non-generic, return statements are contextually typed by the return type of the signature
+            var signature = getContextualSignatureForFunctionLikeDeclaration(functionDecl);
+            if (signature && !isResolvingReturnTypeOfSignature(signature)) {
+                return getReturnTypeOfSignature(signature);
+            }
+            return undefined;
+        }
+        // In a typed function call, an argument or substitution expression is contextually typed by the type of the corresponding parameter.
+        function getContextualTypeForArgument(callTarget, arg) {
+            var args = getEffectiveCallArguments(callTarget); // TODO: GH#18217
+            var argIndex = args.indexOf(arg); // -1 for e.g. the expression of a CallExpression, or the tag of a TaggedTemplateExpression
+            return argIndex === -1 ? undefined : getContextualTypeForArgumentAtIndex(callTarget, argIndex);
+        }
+        function getContextualTypeForArgumentAtIndex(callTarget, argIndex) {
+            // If we're already in the process of resolving the given signature, don't resolve again as
+            // that could cause infinite recursion. Instead, return anySignature.
+            var signature = getNodeLinks(callTarget).resolvedSignature === resolvingSignature ? resolvingSignature : getResolvedSignature(callTarget);
+            return getTypeAtPosition(signature, argIndex);
+        }
+        function getContextualTypeForSubstitutionExpression(template, substitutionExpression) {
+            if (template.parent.kind === 189 /* TaggedTemplateExpression */) {
+                return getContextualTypeForArgument(template.parent, substitutionExpression);
+            }
+            return undefined;
+        }
+        function getContextualTypeForBinaryOperand(node) {
+            var binaryExpression = node.parent;
+            var left = binaryExpression.left, operatorToken = binaryExpression.operatorToken, right = binaryExpression.right;
+            switch (operatorToken.kind) {
+                case 58 /* EqualsToken */:
+                    return node === right && isContextSensitiveAssignment(binaryExpression) ? getTypeOfExpression(left) : undefined;
+                case 54 /* BarBarToken */:
+                    // When an || expression has a contextual type, the operands are contextually typed by that type. When an ||
+                    // expression has no contextual type, the right operand is contextually typed by the type of the left operand,
+                    // except for the special case of Javascript declarations of the form `namespace.prop = namespace.prop || {}`
+                    var type = getContextualType(binaryExpression);
+                    return !type && node === right && !ts.isDefaultedJavascriptInitializer(binaryExpression) ?
+                        getTypeOfExpression(left) : type;
+                case 53 /* AmpersandAmpersandToken */:
+                case 26 /* CommaToken */:
+                    return node === right ? getContextualType(binaryExpression) : undefined;
+                default:
+                    return undefined;
+            }
+        }
+        // In an assignment expression, the right operand is contextually typed by the type of the left operand.
+        // Don't do this for special property assignments to avoid circularity.
+        function isContextSensitiveAssignment(binaryExpression) {
+            var kind = ts.getSpecialPropertyAssignmentKind(binaryExpression);
+            switch (kind) {
+                case 0 /* None */:
+                    return true;
+                case 5 /* Property */:
+                    // If `binaryExpression.left` was assigned a symbol, then this is a new declaration; otherwise it is an assignment to an existing declaration.
+                    // See `bindStaticPropertyAssignment` in `binder.ts`.
+                    return !binaryExpression.left.symbol;
+                case 1 /* ExportsProperty */:
+                case 2 /* ModuleExports */:
+                case 3 /* PrototypeProperty */:
+                case 4 /* ThisProperty */:
+                case 6 /* Prototype */:
+                    return false;
+                default:
+                    return ts.Debug.assertNever(kind);
+            }
+        }
+        function getTypeOfPropertyOfContextualType(type, name) {
+            return mapType(type, function (t) {
+                var prop = t.flags & 917504 /* StructuredType */ ? getPropertyOfType(t, name) : undefined;
+                return prop ? getTypeOfSymbol(prop) : undefined;
+            }, /*noReductions*/ true);
+        }
+        function getIndexTypeOfContextualType(type, kind) {
+            return mapType(type, function (t) { return getIndexTypeOfStructuredType(t, kind); }, /*noReductions*/ true);
+        }
+        // Return true if the given contextual type is a tuple-like type
+        function contextualTypeIsTupleLikeType(type) {
+            return !!(type.flags & 262144 /* Union */ ? ts.forEach(type.types, isTupleLikeType) : isTupleLikeType(type));
+        }
+        // In an object literal contextually typed by a type T, the contextual type of a property assignment is the type of
+        // the matching property in T, if one exists. Otherwise, it is the type of the numeric index signature in T, if one
+        // exists. Otherwise, it is the type of the string index signature in T, if one exists.
+        function getContextualTypeForObjectLiteralMethod(node) {
+            ts.Debug.assert(ts.isObjectLiteralMethod(node));
+            if (node.flags & 8388608 /* InWithStatement */) {
+                // We cannot answer semantic questions within a with block, do not proceed any further
+                return undefined;
+            }
+            return getContextualTypeForObjectLiteralElement(node);
+        }
+        function getContextualTypeForObjectLiteralElement(element) {
+            var objectLiteral = element.parent;
+            var type = getApparentTypeOfContextualType(objectLiteral);
+            if (type) {
+                if (!hasNonBindableDynamicName(element)) {
+                    // For a (non-symbol) computed property, there is no reason to look up the name
+                    // in the type. It will just be "__computed", which does not appear in any
+                    // SymbolTable.
+                    var symbolName_1 = getSymbolOfNode(element).escapedName;
+                    var propertyType = getTypeOfPropertyOfContextualType(type, symbolName_1);
+                    if (propertyType) {
+                        return propertyType;
+                    }
+                }
+                return isNumericName(element.name) && getIndexTypeOfContextualType(type, 1 /* Number */) ||
+                    getIndexTypeOfContextualType(type, 0 /* String */);
+            }
+            return undefined;
+        }
+        // In an array literal contextually typed by a type T, the contextual type of an element expression at index N is
+        // the type of the property with the numeric name N in T, if one exists. Otherwise, if T has a numeric index signature,
+        // it is the type of the numeric index signature in T. Otherwise, in ES6 and higher, the contextual type is the iterated
+        // type of T.
+        function getContextualTypeForElementExpression(arrayContextualType, index) {
+            return arrayContextualType && (getTypeOfPropertyOfContextualType(arrayContextualType, "" + index)
+                || getIndexTypeOfContextualType(arrayContextualType, 1 /* Number */)
+                || getIteratedTypeOrElementType(arrayContextualType, /*errorNode*/ undefined, /*allowStringInput*/ false, /*allowAsyncIterables*/ false, /*checkAssignability*/ false));
+        }
+        // In a contextually typed conditional expression, the true/false expressions are contextually typed by the same type.
+        function getContextualTypeForConditionalOperand(node) {
+            var conditional = node.parent;
+            return node === conditional.whenTrue || node === conditional.whenFalse ? getContextualType(conditional) : undefined;
+        }
+        function getContextualTypeForChildJsxExpression(node) {
+            var attributesType = getApparentTypeOfContextualType(node.openingElement.tagName);
+            // JSX expression is in children of JSX Element, we will look for an "children" atttribute (we get the name from JSX.ElementAttributesProperty)
+            var jsxChildrenPropertyName = getJsxElementChildrenPropertyName(getJsxNamespaceAt(node));
+            return attributesType && !isTypeAny(attributesType) && jsxChildrenPropertyName && jsxChildrenPropertyName !== "" ? getTypeOfPropertyOfContextualType(attributesType, jsxChildrenPropertyName) : undefined;
+        }
+        function getContextualTypeForJsxExpression(node) {
+            var exprParent = node.parent;
+            return ts.isJsxAttributeLike(exprParent)
+                ? getContextualType(node)
+                : ts.isJsxElement(exprParent)
+                    ? getContextualTypeForChildJsxExpression(exprParent)
+                    : undefined;
+        }
+        function getContextualTypeForJsxAttribute(attribute) {
+            // When we trying to resolve JsxOpeningLikeElement as a stateless function element, we will already give its attributes a contextual type
+            // which is a type of the parameter of the signature we are trying out.
+            // If there is no contextual type (e.g. we are trying to resolve stateful component), get attributes type from resolving element's tagName
+            if (ts.isJsxAttribute(attribute)) {
+                var attributesType = getApparentTypeOfContextualType(attribute.parent);
+                if (!attributesType || isTypeAny(attributesType)) {
+                    return undefined;
+                }
+                return getTypeOfPropertyOfContextualType(attributesType, attribute.name.escapedText);
+            }
+            else {
+                return getContextualType(attribute.parent);
+            }
+        }
+        // Return true if the given expression is possibly a discriminant value. We limit the kinds of
+        // expressions we check to those that don't depend on their contextual type in order not to cause
+        // recursive (and possibly infinite) invocations of getContextualType.
+        function isPossiblyDiscriminantValue(node) {
+            switch (node.kind) {
+                case 9 /* StringLiteral */:
+                case 8 /* NumericLiteral */:
+                case 13 /* NoSubstitutionTemplateLiteral */:
+                case 101 /* TrueKeyword */:
+                case 86 /* FalseKeyword */:
+                case 95 /* NullKeyword */:
+                case 71 /* Identifier */:
+                    return true;
+                case 185 /* PropertyAccessExpression */:
+                case 191 /* ParenthesizedExpression */:
+                    return isPossiblyDiscriminantValue(node.expression);
+            }
+            return false;
+        }
+        // Return the contextual type for a given expression node. During overload resolution, a contextual type may temporarily
+        // be "pushed" onto a node using the contextualType property.
+        function getApparentTypeOfContextualType(node) {
+            var contextualType = getContextualType(node);
+            contextualType = contextualType && mapType(contextualType, getApparentType);
+            if (!(contextualType && contextualType.flags & 262144 /* Union */ && ts.isObjectLiteralExpression(node))) {
+                return contextualType;
+            }
+            // Keep the below up-to-date with the work done within `isRelatedTo` by `findMatchingDiscriminantType`
+            var match;
+            propLoop: for (var _i = 0, _a = node.properties; _i < _a.length; _i++) {
+                var prop = _a[_i];
+                if (!prop.symbol)
+                    continue;
+                if (prop.kind !== 270 /* PropertyAssignment */)
+                    continue;
+                if (isPossiblyDiscriminantValue(prop.initializer) && isDiscriminantProperty(contextualType, prop.symbol.escapedName)) {
+                    var discriminatingType = checkExpression(prop.initializer);
+                    for (var _b = 0, _c = contextualType.types; _b < _c.length; _b++) {
+                        var type = _c[_b];
+                        var targetType = getTypeOfPropertyOfType(type, prop.symbol.escapedName);
+                        if (targetType && checkTypeAssignableTo(discriminatingType, targetType, /*errorNode*/ undefined)) {
+                            if (match) {
+                                if (type === match)
+                                    continue; // Finding multiple fields which discriminate to the same type is fine
+                                match = undefined;
+                                break propLoop;
+                            }
+                            match = type;
+                        }
+                    }
+                }
+            }
+            return match || contextualType;
+        }
+        /**
+         * Woah! Do you really want to use this function?
+         *
+         * Unless you're trying to get the *non-apparent* type for a
+         * value-literal type or you're authoring relevant portions of this algorithm,
+         * you probably meant to use 'getApparentTypeOfContextualType'.
+         * Otherwise this may not be very useful.
+         *
+         * In cases where you *are* working on this function, you should understand
+         * when it is appropriate to use 'getContextualType' and 'getApparentTypeOfContextualType'.
+         *
+         *   - Use 'getContextualType' when you are simply going to propagate the result to the expression.
+         *   - Use 'getApparentTypeOfContextualType' when you're going to need the members of the type.
+         *
+         * @param node the expression whose contextual type will be returned.
+         * @returns the contextual type of an expression.
+         */
+        function getContextualType(node) {
+            if (node.flags & 8388608 /* InWithStatement */) {
+                // We cannot answer semantic questions within a with block, do not proceed any further
+                return undefined;
+            }
+            if (node.contextualType) {
+                return node.contextualType;
+            }
+            var parent = node.parent;
+            switch (parent.kind) {
+                case 232 /* VariableDeclaration */:
+                case 149 /* Parameter */:
+                case 152 /* PropertyDeclaration */:
+                case 151 /* PropertySignature */:
+                case 182 /* BindingElement */:
+                    return getContextualTypeForInitializerExpression(node);
+                case 193 /* ArrowFunction */:
+                case 225 /* ReturnStatement */:
+                    return getContextualTypeForReturnExpression(node);
+                case 203 /* YieldExpression */:
+                    return getContextualTypeForYieldOperand(parent);
+                case 187 /* CallExpression */:
+                case 188 /* NewExpression */:
+                    return getContextualTypeForArgument(parent, node);
+                case 190 /* TypeAssertionExpression */:
+                case 208 /* AsExpression */:
+                    return getTypeFromTypeNode(parent.type);
+                case 200 /* BinaryExpression */:
+                    return getContextualTypeForBinaryOperand(node);
+                case 270 /* PropertyAssignment */:
+                case 271 /* ShorthandPropertyAssignment */:
+                    return getContextualTypeForObjectLiteralElement(parent);
+                case 272 /* SpreadAssignment */:
+                    return getApparentTypeOfContextualType(parent.parent);
+                case 183 /* ArrayLiteralExpression */: {
+                    var arrayLiteral = parent;
+                    var type = getApparentTypeOfContextualType(arrayLiteral);
+                    return getContextualTypeForElementExpression(type, ts.indexOfNode(arrayLiteral.elements, node));
+                }
+                case 201 /* ConditionalExpression */:
+                    return getContextualTypeForConditionalOperand(node);
+                case 211 /* TemplateSpan */:
+                    ts.Debug.assert(parent.parent.kind === 202 /* TemplateExpression */);
+                    return getContextualTypeForSubstitutionExpression(parent.parent, node);
+                case 191 /* ParenthesizedExpression */: {
+                    // Like in `checkParenthesizedExpression`, an `/** @type {xyz} */` comment before a parenthesized expression acts as a type cast.
+                    var tag = ts.isInJavaScriptFile(parent) ? ts.getJSDocTypeTag(parent) : undefined;
+                    return tag ? getTypeFromTypeNode(tag.typeExpression.type) : getContextualType(parent);
+                }
+                case 265 /* JsxExpression */:
+                    return getContextualTypeForJsxExpression(parent);
+                case 262 /* JsxAttribute */:
+                case 264 /* JsxSpreadAttribute */:
+                    return getContextualTypeForJsxAttribute(parent);
+                case 257 /* JsxOpeningElement */:
+                case 256 /* JsxSelfClosingElement */:
+                    return getContextualJsxElementAttributesType(parent);
+            }
+            return undefined;
+        }
+        function getContextualMapper(node) {
+            var ancestor = ts.findAncestor(node, function (n) { return !!n.contextualMapper; });
+            return ancestor ? ancestor.contextualMapper : identityMapper;
+        }
+        function getContextualJsxElementAttributesType(node) {
+            if (isJsxIntrinsicIdentifier(node.tagName)) {
+                return getIntrinsicAttributesTypeFromJsxOpeningLikeElement(node);
+            }
+            var valueType = checkExpression(node.tagName);
+            if (isTypeAny(valueType)) {
+                // Short-circuit if the class tag is using an element type 'any'
+                return anyType;
+            }
+            var isJs = ts.isInJavaScriptFile(node);
+            return mapType(valueType, function (t) { return getJsxSignaturesParameterTypes(t, isJs, node); });
+        }
+        function getJsxSignaturesParameterTypes(valueType, isJs, context) {
+            // If the elemType is a string type, we have to return anyType to prevent an error downstream as we will try to find construct or call signature of the type
+            if (valueType.flags & 4 /* String */) {
+                return anyType;
+            }
+            else if (valueType.flags & 64 /* StringLiteral */) {
+                // If the elemType is a stringLiteral type, we can then provide a check to make sure that the string literal type is one of the Jsx intrinsic element type
+                // For example:
+                //      var CustomTag: "h1" = "h1";
+                //      <CustomTag> Hello World </CustomTag>
+                var intrinsicElementsType = getJsxType(JsxNames.IntrinsicElements, context);
+                if (intrinsicElementsType !== errorType) {
+                    var stringLiteralTypeName = valueType.value;
+                    var intrinsicProp = getPropertyOfType(intrinsicElementsType, ts.escapeLeadingUnderscores(stringLiteralTypeName));
+                    if (intrinsicProp) {
+                        return getTypeOfSymbol(intrinsicProp);
+                    }
+                    var indexSignatureType = getIndexTypeOfType(intrinsicElementsType, 0 /* String */);
+                    if (indexSignatureType) {
+                        return indexSignatureType;
+                    }
+                }
+                return anyType;
+            }
+            // Resolve the signatures, preferring constructor
+            var signatures = getSignaturesOfType(valueType, 1 /* Construct */);
+            var ctor = true;
+            if (signatures.length === 0) {
+                // No construct signatures, try call signatures
+                signatures = getSignaturesOfType(valueType, 0 /* Call */);
+                ctor = false;
+                if (signatures.length === 0) {
+                    // We found no signatures at all, which is an error
+                    return errorType;
+                }
+            }
+            var links = getNodeLinks(context);
+            if (!links.resolvedSignatures) {
+                links.resolvedSignatures = ts.createMap();
+            }
+            var cacheKey = "" + getTypeId(valueType);
+            var cachedResolved = links.resolvedSignatures.get(cacheKey);
+            if (cachedResolved && cachedResolved !== resolvingSignaturesArray) {
+                signatures = cachedResolved;
+            }
+            else if (!cachedResolved) {
+                links.resolvedSignatures.set(cacheKey, resolvingSignaturesArray);
+                links.resolvedSignatures.set(cacheKey, signatures = instantiateJsxSignatures(context, signatures));
+            }
+            return getUnionType(ts.map(signatures, ctor ? function (t) { return getJsxPropsTypeFromClassType(t, isJs, context, /*reportErrors*/ false); } : function (t) { return getJsxPropsTypeFromCallSignature(t, context); }), 0 /* None */);
+        }
+        function getJsxPropsTypeFromCallSignature(sig, context) {
+            var propsType = getTypeOfFirstParameterOfSignatureWithFallback(sig, emptyObjectType);
+            var intrinsicAttribs = getJsxType(JsxNames.IntrinsicAttributes, context);
+            if (intrinsicAttribs !== errorType) {
+                propsType = intersectTypes(intrinsicAttribs, propsType);
+            }
+            return propsType;
+        }
+        function getJsxPropsTypeForSignatureFromMember(sig, forcedLookupLocation) {
+            var instanceType = getReturnTypeOfSignature(sig);
+            return isTypeAny(instanceType) ? instanceType : getTypeOfPropertyOfType(instanceType, forcedLookupLocation);
+        }
+        function getJsxPropsTypeFromClassType(sig, isJs, context, reportErrors) {
+            var forcedLookupLocation = getJsxElementPropertiesName(getJsxNamespaceAt(context));
+            var attributesType = forcedLookupLocation === undefined
+                // If there is no type ElementAttributesProperty, return the type of the first parameter of the signature, which should be the props type
+                ? getTypeOfFirstParameterOfSignatureWithFallback(sig, emptyObjectType)
+                : forcedLookupLocation === ""
+                    // If there is no e.g. 'props' member in ElementAttributesProperty, use the element class type instead
+                    ? getReturnTypeOfSignature(sig)
+                    // Otherwise get the type of the property on the signature return type
+                    : getJsxPropsTypeForSignatureFromMember(sig, forcedLookupLocation);
+            if (!attributesType) {
+                // There is no property named 'props' on this instance type
+                if (reportErrors && !!forcedLookupLocation && !!ts.length(context.attributes.properties)) {
+                    error(context, ts.Diagnostics.JSX_element_class_does_not_support_attributes_because_it_does_not_have_a_0_property, ts.unescapeLeadingUnderscores(forcedLookupLocation));
+                }
+                return emptyObjectType;
+            }
+            else if (isTypeAny(attributesType)) {
+                // Props is of type 'any' or unknown
+                return attributesType;
+            }
+            else {
+                // Normal case -- add in IntrinsicClassElements<T> and IntrinsicElements
+                var apparentAttributesType = attributesType;
+                var intrinsicClassAttribs = getJsxType(JsxNames.IntrinsicClassAttributes, context);
+                if (intrinsicClassAttribs !== errorType) {
+                    var typeParams = getLocalTypeParametersOfClassOrInterfaceOrTypeAlias(intrinsicClassAttribs.symbol);
+                    var hostClassType = getReturnTypeOfSignature(sig);
+                    apparentAttributesType = intersectTypes(typeParams
+                        ? createTypeReference(intrinsicClassAttribs, fillMissingTypeArguments([hostClassType], typeParams, getMinTypeArgumentCount(typeParams), isJs))
+                        : intrinsicClassAttribs, apparentAttributesType);
+                }
+                var intrinsicAttribs = getJsxType(JsxNames.IntrinsicAttributes, context);
+                if (intrinsicAttribs !== errorType) {
+                    apparentAttributesType = intersectTypes(intrinsicAttribs, apparentAttributesType);
+                }
+                return apparentAttributesType;
+            }
+        }
+        // If the given type is an object or union type with a single signature, and if that signature has at
+        // least as many parameters as the given function, return the signature. Otherwise return undefined.
+        function getContextualCallSignature(type, node) {
+            var signatures = getSignaturesOfType(type, 0 /* Call */);
+            if (signatures.length === 1) {
+                var signature = signatures[0];
+                if (!isAritySmaller(signature, node)) {
+                    return signature;
+                }
+            }
+        }
+        /** If the contextual signature has fewer parameters than the function expression, do not use it */
+        function isAritySmaller(signature, target) {
+            var targetParameterCount = 0;
+            for (; targetParameterCount < target.parameters.length; targetParameterCount++) {
+                var param = target.parameters[targetParameterCount];
+                if (param.initializer || param.questionToken || param.dotDotDotToken || isJSDocOptionalParameter(param)) {
+                    break;
+                }
+            }
+            if (target.parameters.length && ts.parameterIsThisKeyword(target.parameters[0])) {
+                targetParameterCount--;
+            }
+            var sourceLength = signature.hasRestParameter ? Number.MAX_VALUE : signature.parameters.length;
+            return sourceLength < targetParameterCount;
+        }
+        function isFunctionExpressionOrArrowFunction(node) {
+            return node.kind === 192 /* FunctionExpression */ || node.kind === 193 /* ArrowFunction */;
+        }
+        function getContextualSignatureForFunctionLikeDeclaration(node) {
+            // Only function expressions, arrow functions, and object literal methods are contextually typed.
+            return isFunctionExpressionOrArrowFunction(node) || ts.isObjectLiteralMethod(node)
+                ? getContextualSignature(node)
+                : undefined;
+        }
+        function getContextualTypeForFunctionLikeDeclaration(node) {
+            return ts.isObjectLiteralMethod(node) ?
+                getContextualTypeForObjectLiteralMethod(node) :
+                getApparentTypeOfContextualType(node);
+        }
+        // Return the contextual signature for a given expression node. A contextual type provides a
+        // contextual signature if it has a single call signature and if that call signature is non-generic.
+        // If the contextual type is a union type, get the signature from each type possible and if they are
+        // all identical ignoring their return type, the result is same signature but with return type as
+        // union type of return types from these signatures
+        function getContextualSignature(node) {
+            ts.Debug.assert(node.kind !== 154 /* MethodDeclaration */ || ts.isObjectLiteralMethod(node));
+            var type;
+            if (ts.isInJavaScriptFile(node)) {
+                var jsdoc = ts.getJSDocType(node);
+                if (jsdoc) {
+                    type = getTypeFromTypeNode(jsdoc);
+                }
+            }
+            if (!type) {
+                type = getContextualTypeForFunctionLikeDeclaration(node);
+            }
+            if (!type) {
+                return undefined;
+            }
+            if (!(type.flags & 262144 /* Union */)) {
+                return getContextualCallSignature(type, node);
+            }
+            var signatureList;
+            var types = type.types;
+            for (var _i = 0, types_15 = types; _i < types_15.length; _i++) {
+                var current = types_15[_i];
+                var signature = getContextualCallSignature(current, node);
+                if (signature) {
+                    if (!signatureList) {
+                        // This signature will contribute to contextual union signature
+                        signatureList = [signature];
+                    }
+                    else if (!compareSignaturesIdentical(signatureList[0], signature, /*partialMatch*/ false, /*ignoreThisTypes*/ true, /*ignoreReturnTypes*/ true, compareTypesIdentical)) {
+                        // Signatures aren't identical, do not use
+                        return undefined;
+                    }
+                    else {
+                        // Use this signature for contextual union signature
+                        signatureList.push(signature);
+                    }
+                }
+            }
+            // Result is union of signatures collected (return type is union of return types of this signature set)
+            var result;
+            if (signatureList) {
+                result = cloneSignature(signatureList[0]);
+                result.unionSignatures = signatureList;
+            }
+            return result;
+        }
+        function checkSpreadExpression(node, checkMode) {
+            if (languageVersion < 2 /* ES2015 */ && compilerOptions.downlevelIteration) {
+                checkExternalEmitHelpers(node, 1536 /* SpreadIncludes */);
+            }
+            var arrayOrIterableType = checkExpression(node.expression, checkMode);
+            return checkIteratedTypeOrElementType(arrayOrIterableType, node.expression, /*allowStringInput*/ false, /*allowAsyncIterables*/ false);
+        }
+        function hasDefaultValue(node) {
+            return (node.kind === 182 /* BindingElement */ && !!node.initializer) ||
+                (node.kind === 200 /* BinaryExpression */ && node.operatorToken.kind === 58 /* EqualsToken */);
+        }
+        function checkArrayLiteral(node, checkMode) {
+            var elements = node.elements;
+            var hasSpreadElement = false;
+            var elementTypes = [];
+            var inDestructuringPattern = ts.isAssignmentTarget(node);
+            var contextualType = getApparentTypeOfContextualType(node);
+            for (var index = 0; index < elements.length; index++) {
+                var e = elements[index];
+                if (inDestructuringPattern && e.kind === 204 /* SpreadElement */) {
+                    // Given the following situation:
+                    //    var c: {};
+                    //    [...c] = ["", 0];
+                    //
+                    // c is represented in the tree as a spread element in an array literal.
+                    // But c really functions as a rest element, and its purpose is to provide
+                    // a contextual type for the right hand side of the assignment. Therefore,
+                    // instead of calling checkExpression on "...c", which will give an error
+                    // if c is not iterable/array-like, we need to act as if we are trying to
+                    // get the contextual element type from it. So we do something similar to
+                    // getContextualTypeForElementExpression, which will crucially not error
+                    // if there is no index type / iterated type.
+                    var restArrayType = checkExpression(e.expression, checkMode);
+                    var restElementType = getIndexTypeOfType(restArrayType, 1 /* Number */) ||
+                        getIteratedTypeOrElementType(restArrayType, /*errorNode*/ undefined, /*allowStringInput*/ false, /*allowAsyncIterables*/ false, /*checkAssignability*/ false);
+                    if (restElementType) {
+                        elementTypes.push(restElementType);
+                    }
+                }
+                else {
+                    var elementContextualType = getContextualTypeForElementExpression(contextualType, index);
+                    var type = checkExpressionForMutableLocation(e, checkMode, elementContextualType);
+                    elementTypes.push(type);
+                }
+                hasSpreadElement = hasSpreadElement || e.kind === 204 /* SpreadElement */;
+            }
+            if (!hasSpreadElement) {
+                // If array literal is actually a destructuring pattern, mark it as an implied type. We do this such
+                // that we get the same behavior for "var [x, y] = []" and "[x, y] = []".
+                if (inDestructuringPattern && elementTypes.length) {
+                    var type = cloneTypeReference(createTupleType(elementTypes));
+                    type.pattern = node;
+                    return type;
+                }
+                if (contextualType && contextualTypeIsTupleLikeType(contextualType)) {
+                    var pattern = contextualType.pattern;
+                    // If array literal is contextually typed by a binding pattern or an assignment pattern, pad the resulting
+                    // tuple type with the corresponding binding or assignment element types to make the lengths equal.
+                    if (pattern && (pattern.kind === 181 /* ArrayBindingPattern */ || pattern.kind === 183 /* ArrayLiteralExpression */)) {
+                        var patternElements = pattern.elements;
+                        for (var i = elementTypes.length; i < patternElements.length; i++) {
+                            var patternElement = patternElements[i];
+                            if (hasDefaultValue(patternElement)) {
+                                elementTypes.push(contextualType.typeArguments[i]);
+                            }
+                            else {
+                                if (patternElement.kind !== 206 /* OmittedExpression */) {
+                                    error(patternElement, ts.Diagnostics.Initializer_provides_no_value_for_this_binding_element_and_the_binding_element_has_no_default_value);
+                                }
+                                elementTypes.push(strictNullChecks ? implicitNeverType : undefinedWideningType);
+                            }
+                        }
+                    }
+                    if (elementTypes.length) {
+                        return createTupleType(elementTypes);
+                    }
+                }
+            }
+            return createArrayType(elementTypes.length ?
+                getUnionType(elementTypes, 2 /* Subtype */) :
+                strictNullChecks ? implicitNeverType : undefinedWideningType);
+        }
+        function isNumericName(name) {
+            switch (name.kind) {
+                case 147 /* ComputedPropertyName */:
+                    return isNumericComputedName(name);
+                case 71 /* Identifier */:
+                    return isNumericLiteralName(name.escapedText);
+                case 8 /* NumericLiteral */:
+                case 9 /* StringLiteral */:
+                    return isNumericLiteralName(name.text);
+                default:
+                    return false;
+            }
+        }
+        function isNumericComputedName(name) {
+            // It seems odd to consider an expression of type Any to result in a numeric name,
+            // but this behavior is consistent with checkIndexedAccess
+            return isTypeAssignableToKind(checkComputedPropertyName(name), 168 /* NumberLike */);
+        }
+        function isInfinityOrNaNString(name) {
+            return name === "Infinity" || name === "-Infinity" || name === "NaN";
+        }
+        function isNumericLiteralName(name) {
+            // The intent of numeric names is that
+            //     - they are names with text in a numeric form, and that
+            //     - setting properties/indexing with them is always equivalent to doing so with the numeric literal 'numLit',
+            //         acquired by applying the abstract 'ToNumber' operation on the name's text.
+            //
+            // The subtlety is in the latter portion, as we cannot reliably say that anything that looks like a numeric literal is a numeric name.
+            // In fact, it is the case that the text of the name must be equal to 'ToString(numLit)' for this to hold.
+            //
+            // Consider the property name '"0xF00D"'. When one indexes with '0xF00D', they are actually indexing with the value of 'ToString(0xF00D)'
+            // according to the ECMAScript specification, so it is actually as if the user indexed with the string '"61453"'.
+            // Thus, the text of all numeric literals equivalent to '61543' such as '0xF00D', '0xf00D', '0170015', etc. are not valid numeric names
+            // because their 'ToString' representation is not equal to their original text.
+            // This is motivated by ECMA-262 sections 9.3.1, 9.8.1, 11.1.5, and 11.2.1.
+            //
+            // Here, we test whether 'ToString(ToNumber(name))' is exactly equal to 'name'.
+            // The '+' prefix operator is equivalent here to applying the abstract ToNumber operation.
+            // Applying the 'toString()' method on a number gives us the abstract ToString operation on a number.
+            //
+            // Note that this accepts the values 'Infinity', '-Infinity', and 'NaN', and that this is intentional.
+            // This is desired behavior, because when indexing with them as numeric entities, you are indexing
+            // with the strings '"Infinity"', '"-Infinity"', and '"NaN"' respectively.
+            return (+name).toString() === name;
+        }
+        function checkComputedPropertyName(node) {
+            var links = getNodeLinks(node.expression);
+            if (!links.resolvedType) {
+                links.resolvedType = checkExpression(node.expression);
+                // This will allow types number, string, symbol or any. It will also allow enums, the unknown
+                // type, and any union of these types (like string | number).
+                if (links.resolvedType.flags & 24576 /* Nullable */ ||
+                    !isTypeAssignableToKind(links.resolvedType, 68 /* StringLike */ | 168 /* NumberLike */ | 3072 /* ESSymbolLike */) &&
+                        !isTypeAssignableTo(links.resolvedType, stringNumberSymbolType)) {
+                    error(node, ts.Diagnostics.A_computed_property_name_must_be_of_type_string_number_symbol_or_any);
+                }
+                else {
+                    checkThatExpressionIsProperSymbolReference(node.expression, links.resolvedType, /*reportError*/ true);
+                }
+            }
+            return links.resolvedType;
+        }
+        function getObjectLiteralIndexInfo(propertyNodes, offset, properties, kind) {
+            var propTypes = [];
+            for (var i = 0; i < properties.length; i++) {
+                if (kind === 0 /* String */ || isNumericName(propertyNodes[i + offset].name)) {
+                    propTypes.push(getTypeOfSymbol(properties[i]));
+                }
+            }
+            var unionType = propTypes.length ? getUnionType(propTypes, 2 /* Subtype */) : undefinedType;
+            return createIndexInfo(unionType, /*isReadonly*/ false);
+        }
+        function checkObjectLiteral(node, checkMode) {
+            var inDestructuringPattern = ts.isAssignmentTarget(node);
+            // Grammar checking
+            checkGrammarObjectLiteralExpression(node, inDestructuringPattern);
+            var propertiesTable;
+            var propertiesArray = [];
+            var spread = emptyObjectType;
+            var propagatedFlags = 33554432 /* FreshLiteral */;
+            var contextualType = getApparentTypeOfContextualType(node);
+            var contextualTypeHasPattern = contextualType && contextualType.pattern &&
+                (contextualType.pattern.kind === 180 /* ObjectBindingPattern */ || contextualType.pattern.kind === 184 /* ObjectLiteralExpression */);
+            var isInJSFile = ts.isInJavaScriptFile(node) && !ts.isInJsonFile(node);
+            var isJSObjectLiteral = !contextualType && isInJSFile;
+            var typeFlags = 0;
+            var patternWithComputedProperties = false;
+            var hasComputedStringProperty = false;
+            var hasComputedNumberProperty = false;
+            if (isInJSFile) {
+                var decl = ts.getDeclarationOfJSInitializer(node);
+                if (decl) {
+                    // a JS object literal whose declaration's symbol has exports is a JS namespace
+                    var symbol = getSymbolOfNode(decl);
+                    if (symbol && ts.hasEntries(symbol.exports)) {
+                        propertiesTable = symbol.exports;
+                        symbol.exports.forEach(function (s) { return propertiesArray.push(getMergedSymbol(s)); });
+                        return createObjectLiteralType();
+                    }
+                }
+            }
+            propertiesTable = ts.createSymbolTable();
+            var offset = 0;
+            for (var i = 0; i < node.properties.length; i++) {
+                var memberDecl = node.properties[i];
+                var member = getSymbolOfNode(memberDecl);
+                var computedNameType = memberDecl.name && memberDecl.name.kind === 147 /* ComputedPropertyName */ && !ts.isWellKnownSymbolSyntactically(memberDecl.name.expression) ?
+                    checkComputedPropertyName(memberDecl.name) : undefined;
+                if (memberDecl.kind === 270 /* PropertyAssignment */ ||
+                    memberDecl.kind === 271 /* ShorthandPropertyAssignment */ ||
+                    ts.isObjectLiteralMethod(memberDecl)) {
+                    var type = memberDecl.kind === 270 /* PropertyAssignment */ ? checkPropertyAssignment(memberDecl, checkMode) :
+                        memberDecl.kind === 271 /* ShorthandPropertyAssignment */ ? checkExpressionForMutableLocation(memberDecl.name, checkMode) :
+                            checkObjectLiteralMethod(memberDecl, checkMode);
+                    if (isInJSFile) {
+                        var jsDocType = getTypeForDeclarationFromJSDocComment(memberDecl);
+                        if (jsDocType) {
+                            checkTypeAssignableTo(type, jsDocType, memberDecl);
+                            type = jsDocType;
+                        }
+                    }
+                    typeFlags |= type.flags;
+                    var nameType = computedNameType && computedNameType.flags & 2240 /* StringOrNumberLiteralOrUnique */ ?
+                        computedNameType : undefined;
+                    var prop = nameType ?
+                        createSymbol(4 /* Property */ | member.flags, getLateBoundNameFromType(nameType), 1024 /* Late */) :
+                        createSymbol(4 /* Property */ | member.flags, member.escapedName);
+                    if (nameType) {
+                        prop.nameType = nameType;
+                    }
+                    if (inDestructuringPattern) {
+                        // If object literal is an assignment pattern and if the assignment pattern specifies a default value
+                        // for the property, make the property optional.
+                        var isOptional = (memberDecl.kind === 270 /* PropertyAssignment */ && hasDefaultValue(memberDecl.initializer)) ||
+                            (memberDecl.kind === 271 /* ShorthandPropertyAssignment */ && memberDecl.objectAssignmentInitializer);
+                        if (isOptional) {
+                            prop.flags |= 16777216 /* Optional */;
+                        }
+                    }
+                    else if (contextualTypeHasPattern && !(ts.getObjectFlags(contextualType) & 512 /* ObjectLiteralPatternWithComputedProperties */)) {
+                        // If object literal is contextually typed by the implied type of a binding pattern, and if the
+                        // binding pattern specifies a default value for the property, make the property optional.
+                        var impliedProp = getPropertyOfType(contextualType, member.escapedName);
+                        if (impliedProp) {
+                            prop.flags |= impliedProp.flags & 16777216 /* Optional */;
+                        }
+                        else if (!compilerOptions.suppressExcessPropertyErrors && !getIndexInfoOfType(contextualType, 0 /* String */)) {
+                            error(memberDecl.name, ts.Diagnostics.Object_literal_may_only_specify_known_properties_and_0_does_not_exist_in_type_1, symbolToString(member), typeToString(contextualType));
+                        }
+                    }
+                    prop.declarations = member.declarations;
+                    prop.parent = member.parent;
+                    if (member.valueDeclaration) {
+                        prop.valueDeclaration = member.valueDeclaration;
+                    }
+                    prop.type = type;
+                    prop.target = member;
+                    member = prop;
+                }
+                else if (memberDecl.kind === 272 /* SpreadAssignment */) {
+                    if (languageVersion < 2 /* ES2015 */) {
+                        checkExternalEmitHelpers(memberDecl, 2 /* Assign */);
+                    }
+                    if (propertiesArray.length > 0) {
+                        spread = getSpreadType(spread, createObjectLiteralType(), node.symbol, propagatedFlags, /*objectFlags*/ 0);
+                        propertiesArray = [];
+                        propertiesTable = ts.createSymbolTable();
+                        hasComputedStringProperty = false;
+                        hasComputedNumberProperty = false;
+                        typeFlags = 0;
+                    }
+                    var type = checkExpression(memberDecl.expression);
+                    if (!isValidSpreadType(type)) {
+                        error(memberDecl, ts.Diagnostics.Spread_types_may_only_be_created_from_object_types);
+                        return errorType;
+                    }
+                    spread = getSpreadType(spread, type, node.symbol, propagatedFlags, /*objectFlags*/ 0);
+                    offset = i + 1;
+                    continue;
+                }
+                else {
+                    // TypeScript 1.0 spec (April 2014)
+                    // A get accessor declaration is processed in the same manner as
+                    // an ordinary function declaration(section 6.1) with no parameters.
+                    // A set accessor declaration is processed in the same manner
+                    // as an ordinary function declaration with a single parameter and a Void return type.
+                    ts.Debug.assert(memberDecl.kind === 156 /* GetAccessor */ || memberDecl.kind === 157 /* SetAccessor */);
+                    checkNodeDeferred(memberDecl);
+                }
+                if (computedNameType && !(computedNameType.flags & 2240 /* StringOrNumberLiteralOrUnique */)) {
+                    if (isTypeAssignableTo(computedNameType, stringNumberSymbolType)) {
+                        if (isTypeAssignableTo(computedNameType, numberType)) {
+                            hasComputedNumberProperty = true;
+                        }
+                        else {
+                            hasComputedStringProperty = true;
+                        }
+                        if (inDestructuringPattern) {
+                            patternWithComputedProperties = true;
+                        }
+                    }
+                }
+                else {
+                    propertiesTable.set(member.escapedName, member);
+                }
+                propertiesArray.push(member);
+            }
+            // If object literal is contextually typed by the implied type of a binding pattern, augment the result
+            // type with those properties for which the binding pattern specifies a default value.
+            if (contextualTypeHasPattern) {
+                for (var _i = 0, _a = getPropertiesOfType(contextualType); _i < _a.length; _i++) {
+                    var prop = _a[_i];
+                    if (!propertiesTable.get(prop.escapedName) && !(spread && getPropertyOfType(spread, prop.escapedName))) {
+                        if (!(prop.flags & 16777216 /* Optional */)) {
+                            error(prop.valueDeclaration || prop.bindingElement, ts.Diagnostics.Initializer_provides_no_value_for_this_binding_element_and_the_binding_element_has_no_default_value);
+                        }
+                        propertiesTable.set(prop.escapedName, prop);
+                        propertiesArray.push(prop);
+                    }
+                }
+            }
+            if (spread !== emptyObjectType) {
+                if (propertiesArray.length > 0) {
+                    spread = getSpreadType(spread, createObjectLiteralType(), node.symbol, propagatedFlags, /*objectFlags*/ 0);
+                }
+                return spread;
+            }
+            return createObjectLiteralType();
+            function createObjectLiteralType() {
+                var stringIndexInfo = isJSObjectLiteral ? jsObjectLiteralIndexInfo : hasComputedStringProperty ? getObjectLiteralIndexInfo(node.properties, offset, propertiesArray, 0 /* String */) : undefined;
+                var numberIndexInfo = hasComputedNumberProperty && !isJSObjectLiteral ? getObjectLiteralIndexInfo(node.properties, offset, propertiesArray, 1 /* Number */) : undefined;
+                var result = createAnonymousType(node.symbol, propertiesTable, ts.emptyArray, ts.emptyArray, stringIndexInfo, numberIndexInfo);
+                var freshObjectLiteralFlag = compilerOptions.suppressExcessPropertyErrors ? 0 : 33554432 /* FreshLiteral */;
+                result.flags |= 268435456 /* ContainsObjectLiteral */ | freshObjectLiteralFlag | (typeFlags & 939524096 /* PropagatingFlags */);
+                result.objectFlags |= 128 /* ObjectLiteral */;
+                if (patternWithComputedProperties) {
+                    result.objectFlags |= 512 /* ObjectLiteralPatternWithComputedProperties */;
+                }
+                if (inDestructuringPattern) {
+                    result.pattern = node;
+                }
+                if (!(result.flags & 24576 /* Nullable */)) {
+                    propagatedFlags |= (result.flags & 939524096 /* PropagatingFlags */);
+                }
+                return result;
+            }
+        }
+        function isValidSpreadType(type) {
+            return !!(type.flags & (3 /* AnyOrUnknown */ | 16777216 /* NonPrimitive */) ||
+                getFalsyFlags(type) & 29120 /* DefinitelyFalsy */ && isValidSpreadType(removeDefinitelyFalsyTypes(type)) ||
+                type.flags & 131072 /* Object */ && !isGenericMappedType(type) ||
+                type.flags & 786432 /* UnionOrIntersection */ && ts.every(type.types, isValidSpreadType));
+        }
+        function checkJsxSelfClosingElement(node, checkMode) {
+            checkJsxOpeningLikeElementOrOpeningFragment(node, checkMode);
+            return getJsxElementTypeAt(node) || anyType;
+        }
+        function checkJsxElement(node, checkMode) {
+            // Check attributes
+            checkJsxOpeningLikeElementOrOpeningFragment(node.openingElement, checkMode);
+            // Perform resolution on the closing tag so that rename/go to definition/etc work
+            if (isJsxIntrinsicIdentifier(node.closingElement.tagName)) {
+                getIntrinsicTagSymbol(node.closingElement);
+            }
+            else {
+                checkExpression(node.closingElement.tagName);
+            }
+            return getJsxElementTypeAt(node) || anyType;
+        }
+        function checkJsxFragment(node, checkMode) {
+            checkJsxOpeningLikeElementOrOpeningFragment(node.openingFragment, checkMode);
+            if (compilerOptions.jsx === 2 /* React */ && (compilerOptions.jsxFactory || ts.getSourceFileOfNode(node).pragmas.has("jsx"))) {
+                error(node, compilerOptions.jsxFactory
+                    ? ts.Diagnostics.JSX_fragment_is_not_supported_when_using_jsxFactory
+                    : ts.Diagnostics.JSX_fragment_is_not_supported_when_using_an_inline_JSX_factory_pragma);
+            }
+            return getJsxElementTypeAt(node) || anyType;
+        }
+        /**
+         * Returns true iff the JSX element name would be a valid JS identifier, ignoring restrictions about keywords not being identifiers
+         */
+        function isUnhyphenatedJsxName(name) {
+            // - is the only character supported in JSX attribute names that isn't valid in JavaScript identifiers
+            return !ts.stringContains(name, "-");
+        }
+        /**
+         * Returns true iff React would emit this tag name as a string rather than an identifier or qualified name
+         */
+        function isJsxIntrinsicIdentifier(tagName) {
+            // TODO (yuisu): comment
+            switch (tagName.kind) {
+                case 185 /* PropertyAccessExpression */:
+                case 99 /* ThisKeyword */:
+                    return false;
+                case 71 /* Identifier */:
+                    return ts.isIntrinsicJsxName(tagName.escapedText);
+                default:
+                    return ts.Debug.fail();
+            }
+        }
+        function checkJsxAttribute(node, checkMode) {
+            return node.initializer
+                ? checkExpressionForMutableLocation(node.initializer, checkMode)
+                : trueType; // <Elem attr /> is sugar for <Elem attr={true} />
+        }
+        /**
+         * Get attributes type of the JSX opening-like element. The result is from resolving "attributes" property of the opening-like element.
+         *
+         * @param openingLikeElement a JSX opening-like element
+         * @param filter a function to remove attributes that will not participate in checking whether attributes are assignable
+         * @return an anonymous type (similar to the one returned by checkObjectLiteral) in which its properties are attributes property.
+         * @remarks Because this function calls getSpreadType, it needs to use the same checks as checkObjectLiteral,
+         * which also calls getSpreadType.
+         */
+        function createJsxAttributesTypeFromAttributesProperty(openingLikeElement, checkMode) {
+            var attributes = openingLikeElement.attributes;
+            var attributesTable = ts.createSymbolTable();
+            var spread = emptyObjectType;
+            var hasSpreadAnyType = false;
+            var typeToIntersect;
+            var explicitlySpecifyChildrenAttribute = false;
+            var jsxChildrenPropertyName = getJsxElementChildrenPropertyName(getJsxNamespaceAt(openingLikeElement));
+            for (var _i = 0, _a = attributes.properties; _i < _a.length; _i++) {
+                var attributeDecl = _a[_i];
+                var member = attributeDecl.symbol;
+                if (ts.isJsxAttribute(attributeDecl)) {
+                    var exprType = checkJsxAttribute(attributeDecl, checkMode);
+                    var attributeSymbol = createSymbol(4 /* Property */ | 33554432 /* Transient */ | member.flags, member.escapedName);
+                    attributeSymbol.declarations = member.declarations;
+                    attributeSymbol.parent = member.parent;
+                    if (member.valueDeclaration) {
+                        attributeSymbol.valueDeclaration = member.valueDeclaration;
+                    }
+                    attributeSymbol.type = exprType;
+                    attributeSymbol.target = member;
+                    attributesTable.set(attributeSymbol.escapedName, attributeSymbol);
+                    if (attributeDecl.name.escapedText === jsxChildrenPropertyName) {
+                        explicitlySpecifyChildrenAttribute = true;
+                    }
+                }
+                else {
+                    ts.Debug.assert(attributeDecl.kind === 264 /* JsxSpreadAttribute */);
+                    if (attributesTable.size > 0) {
+                        spread = getSpreadType(spread, createJsxAttributesType(), attributes.symbol, /*typeFlags*/ 0, 4096 /* JsxAttributes */);
+                        attributesTable = ts.createSymbolTable();
+                    }
+                    var exprType = checkExpressionCached(attributeDecl.expression, checkMode);
+                    if (isTypeAny(exprType)) {
+                        hasSpreadAnyType = true;
+                    }
+                    if (isValidSpreadType(exprType)) {
+                        spread = getSpreadType(spread, exprType, openingLikeElement.symbol, /*typeFlags*/ 0, 4096 /* JsxAttributes */);
+                    }
+                    else {
+                        typeToIntersect = typeToIntersect ? getIntersectionType([typeToIntersect, exprType]) : exprType;
+                    }
+                }
+            }
+            if (!hasSpreadAnyType) {
+                if (attributesTable.size > 0) {
+                    spread = getSpreadType(spread, createJsxAttributesType(), attributes.symbol, /*typeFlags*/ 0, 4096 /* JsxAttributes */);
+                }
+            }
+            // Handle children attribute
+            var parent = openingLikeElement.parent.kind === 255 /* JsxElement */ ? openingLikeElement.parent : undefined;
+            // We have to check that openingElement of the parent is the one we are visiting as this may not be true for selfClosingElement
+            if (parent && parent.openingElement === openingLikeElement && parent.children.length > 0) {
+                var childrenTypes = checkJsxChildren(parent, checkMode);
+                if (!hasSpreadAnyType && jsxChildrenPropertyName && jsxChildrenPropertyName !== "") {
+                    // Error if there is a attribute named "children" explicitly specified and children element.
+                    // This is because children element will overwrite the value from attributes.
+                    // Note: we will not warn "children" attribute overwritten if "children" attribute is specified in object spread.
+                    if (explicitlySpecifyChildrenAttribute) {
+                        error(attributes, ts.Diagnostics._0_are_specified_twice_The_attribute_named_0_will_be_overwritten, ts.unescapeLeadingUnderscores(jsxChildrenPropertyName));
+                    }
+                    // If there are children in the body of JSX element, create dummy attribute "children" with the union of children types so that it will pass the attribute checking process
+                    var childrenPropSymbol = createSymbol(4 /* Property */ | 33554432 /* Transient */, jsxChildrenPropertyName);
+                    childrenPropSymbol.type = childrenTypes.length === 1 ?
+                        childrenTypes[0] :
+                        createArrayType(getUnionType(childrenTypes));
+                    var childPropMap = ts.createSymbolTable();
+                    childPropMap.set(jsxChildrenPropertyName, childrenPropSymbol);
+                    spread = getSpreadType(spread, createAnonymousType(attributes.symbol, childPropMap, ts.emptyArray, ts.emptyArray, /*stringIndexInfo*/ undefined, /*numberIndexInfo*/ undefined), attributes.symbol, /*typeFlags*/ 0, 4096 /* JsxAttributes */);
+                }
+            }
+            if (hasSpreadAnyType) {
+                return anyType;
+            }
+            if (typeToIntersect && spread !== emptyObjectType) {
+                return getIntersectionType([typeToIntersect, spread]);
+            }
+            return typeToIntersect || (spread === emptyObjectType ? createJsxAttributesType() : spread);
+            /**
+             * Create anonymous type from given attributes symbol table.
+             * @param symbol a symbol of JsxAttributes containing attributes corresponding to attributesTable
+             * @param attributesTable a symbol table of attributes property
+             */
+            function createJsxAttributesType() {
+                var result = createAnonymousType(attributes.symbol, attributesTable, ts.emptyArray, ts.emptyArray, /*stringIndexInfo*/ undefined, /*numberIndexInfo*/ undefined);
+                result.flags |= 268435456 /* ContainsObjectLiteral */;
+                result.objectFlags |= 128 /* ObjectLiteral */ | 4096 /* JsxAttributes */;
+                return result;
+            }
+        }
+        function checkJsxChildren(node, checkMode) {
+            var childrenTypes = [];
+            for (var _i = 0, _a = node.children; _i < _a.length; _i++) {
+                var child = _a[_i];
+                // In React, JSX text that contains only whitespaces will be ignored so we don't want to type-check that
+                // because then type of children property will have constituent of string type.
+                if (child.kind === 10 /* JsxText */) {
+                    if (!child.containsOnlyWhiteSpaces) {
+                        childrenTypes.push(stringType);
+                    }
+                }
+                else {
+                    childrenTypes.push(checkExpressionForMutableLocation(child, checkMode));
+                }
+            }
+            return childrenTypes;
+        }
+        /**
+         * Check attributes property of opening-like element. This function is called during chooseOverload to get call signature of a JSX opening-like element.
+         * (See "checkApplicableSignatureForJsxOpeningLikeElement" for how the function is used)
+         * @param node a JSXAttributes to be resolved of its type
+         */
+        function checkJsxAttributes(node, checkMode) {
+            return createJsxAttributesTypeFromAttributesProperty(node.parent, checkMode);
+        }
+        function getJsxType(name, location) {
+            var namespace = getJsxNamespaceAt(location);
+            var exports = namespace && getExportsOfSymbol(namespace);
+            var typeSymbol = exports && getSymbol(exports, name, 67901928 /* Type */);
+            return typeSymbol ? getDeclaredTypeOfSymbol(typeSymbol) : errorType;
+        }
+        /**
+         * Looks up an intrinsic tag name and returns a symbol that either points to an intrinsic
+         * property (in which case nodeLinks.jsxFlags will be IntrinsicNamedElement) or an intrinsic
+         * string index signature (in which case nodeLinks.jsxFlags will be IntrinsicIndexedElement).
+         * May also return unknownSymbol if both of these lookups fail.
+         */
+        function getIntrinsicTagSymbol(node) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedSymbol) {
+                var intrinsicElementsType = getJsxType(JsxNames.IntrinsicElements, node);
+                if (intrinsicElementsType !== errorType) {
+                    // Property case
+                    if (!ts.isIdentifier(node.tagName))
+                        return ts.Debug.fail();
+                    var intrinsicProp = getPropertyOfType(intrinsicElementsType, node.tagName.escapedText);
+                    if (intrinsicProp) {
+                        links.jsxFlags |= 1 /* IntrinsicNamedElement */;
+                        return links.resolvedSymbol = intrinsicProp;
+                    }
+                    // Intrinsic string indexer case
+                    var indexSignatureType = getIndexTypeOfType(intrinsicElementsType, 0 /* String */);
+                    if (indexSignatureType) {
+                        links.jsxFlags |= 2 /* IntrinsicIndexedElement */;
+                        return links.resolvedSymbol = intrinsicElementsType.symbol;
+                    }
+                    // Wasn't found
+                    error(node, ts.Diagnostics.Property_0_does_not_exist_on_type_1, ts.idText(node.tagName), "JSX." + JsxNames.IntrinsicElements);
+                    return links.resolvedSymbol = unknownSymbol;
+                }
+                else {
+                    if (noImplicitAny) {
+                        error(node, ts.Diagnostics.JSX_element_implicitly_has_type_any_because_no_interface_JSX_0_exists, ts.unescapeLeadingUnderscores(JsxNames.IntrinsicElements));
+                    }
+                    return links.resolvedSymbol = unknownSymbol;
+                }
+            }
+            return links.resolvedSymbol;
+        }
+        function instantiateJsxSignatures(node, signatures) {
+            var instantiatedSignatures = [];
+            var candidateForTypeArgumentError;
+            var hasTypeArgumentError = !!node.typeArguments;
+            for (var _i = 0, signatures_3 = signatures; _i < signatures_3.length; _i++) {
+                var signature = signatures_3[_i];
+                if (signature.typeParameters) {
+                    var isJavascript = ts.isInJavaScriptFile(node);
+                    var typeArgumentInstantiated = getJsxSignatureTypeArgumentInstantiation(signature, node, isJavascript, /*reportErrors*/ false);
+                    if (typeArgumentInstantiated) {
+                        hasTypeArgumentError = false;
+                        instantiatedSignatures.push(typeArgumentInstantiated);
+                    }
+                    else {
+                        if (node.typeArguments && hasCorrectTypeArgumentArity(signature, node.typeArguments)) {
+                            candidateForTypeArgumentError = signature;
+                        }
+                        var inferenceContext = createInferenceContext(signature.typeParameters, signature, /*flags*/ isJavascript ? 4 /* AnyDefault */ : 0 /* None */);
+                        var typeArguments = inferJsxTypeArguments(signature, node, inferenceContext);
+                        instantiatedSignatures.push(getSignatureInstantiation(signature, typeArguments, isJavascript));
+                    }
+                }
+                else {
+                    instantiatedSignatures.push(signature);
+                }
+            }
+            if (node.typeArguments && hasTypeArgumentError) {
+                if (candidateForTypeArgumentError) {
+                    checkTypeArguments(candidateForTypeArgumentError, node.typeArguments, /*reportErrors*/ true);
+                }
+                // Length check to avoid issuing an arity error on length=0, the "Type argument list cannot be empty" grammar error alone is fine
+                else if (node.typeArguments.length !== 0) {
+                    diagnostics.add(getTypeArgumentArityError(node, signatures, node.typeArguments));
+                }
+            }
+            return instantiatedSignatures;
+        }
+        function getJsxSignatureTypeArgumentInstantiation(signature, node, isJavascript, reportErrors) {
+            if (reportErrors === void 0) { reportErrors = false; }
+            if (!node.typeArguments) {
+                return;
+            }
+            if (!hasCorrectTypeArgumentArity(signature, node.typeArguments)) {
+                return;
+            }
+            var args = checkTypeArguments(signature, node.typeArguments, reportErrors);
+            if (!args) {
+                return;
+            }
+            return getSignatureInstantiation(signature, args, isJavascript);
+        }
+        function getJsxNamespaceAt(location) {
+            var namespaceName = getJsxNamespace(location);
+            var resolvedNamespace = resolveName(location, namespaceName, 1920 /* Namespace */, /*diagnosticMessage*/ undefined, namespaceName, /*isUse*/ false);
+            if (resolvedNamespace) {
+                var candidate = getSymbol(getExportsOfSymbol(resolveSymbol(resolvedNamespace)), JsxNames.JSX, 1920 /* Namespace */);
+                if (candidate) {
+                    return candidate;
+                }
+            }
+            // JSX global fallback
+            return getGlobalSymbol(JsxNames.JSX, 1920 /* Namespace */, /*diagnosticMessage*/ undefined); // TODO: GH#18217
+        }
+        /**
+         * Look into JSX namespace and then look for container with matching name as nameOfAttribPropContainer.
+         * Get a single property from that container if existed. Report an error if there are more than one property.
+         *
+         * @param nameOfAttribPropContainer a string of value JsxNames.ElementAttributesPropertyNameContainer or JsxNames.ElementChildrenAttributeNameContainer
+         *          if other string is given or the container doesn't exist, return undefined.
+         */
+        function getNameFromJsxElementAttributesContainer(nameOfAttribPropContainer, jsxNamespace) {
+            // JSX.ElementAttributesProperty | JSX.ElementChildrenAttribute [symbol]
+            var jsxElementAttribPropInterfaceSym = jsxNamespace && getSymbol(jsxNamespace.exports, nameOfAttribPropContainer, 67901928 /* Type */);
+            // JSX.ElementAttributesProperty | JSX.ElementChildrenAttribute [type]
+            var jsxElementAttribPropInterfaceType = jsxElementAttribPropInterfaceSym && getDeclaredTypeOfSymbol(jsxElementAttribPropInterfaceSym);
+            // The properties of JSX.ElementAttributesProperty | JSX.ElementChildrenAttribute
+            var propertiesOfJsxElementAttribPropInterface = jsxElementAttribPropInterfaceType && getPropertiesOfType(jsxElementAttribPropInterfaceType);
+            if (propertiesOfJsxElementAttribPropInterface) {
+                // Element Attributes has zero properties, so the element attributes type will be the class instance type
+                if (propertiesOfJsxElementAttribPropInterface.length === 0) {
+                    return "";
+                }
+                // Element Attributes has one property, so the element attributes type will be the type of the corresponding
+                // property of the class instance type
+                else if (propertiesOfJsxElementAttribPropInterface.length === 1) {
+                    return propertiesOfJsxElementAttribPropInterface[0].escapedName;
+                }
+                else if (propertiesOfJsxElementAttribPropInterface.length > 1) {
+                    // More than one property on ElementAttributesProperty is an error
+                    error(jsxElementAttribPropInterfaceSym.declarations[0], ts.Diagnostics.The_global_type_JSX_0_may_not_have_more_than_one_property, ts.unescapeLeadingUnderscores(nameOfAttribPropContainer));
+                }
+            }
+            return undefined;
+        }
+        /// e.g. "props" for React.d.ts,
+        /// or 'undefined' if ElementAttributesProperty doesn't exist (which means all
+        ///     non-intrinsic elements' attributes type is 'any'),
+        /// or '' if it has 0 properties (which means every
+        ///     non-intrinsic elements' attributes type is the element instance type)
+        function getJsxElementPropertiesName(jsxNamespace) {
+            return getNameFromJsxElementAttributesContainer(JsxNames.ElementAttributesPropertyNameContainer, jsxNamespace);
+        }
+        function getJsxElementChildrenPropertyName(jsxNamespace) {
+            return getNameFromJsxElementAttributesContainer(JsxNames.ElementChildrenAttributeNameContainer, jsxNamespace);
+        }
+        function getApparentTypeOfJsxPropsType(propsType) {
+            if (!propsType) {
+                return undefined;
+            }
+            if (propsType.flags & 524288 /* Intersection */) {
+                var propsApparentType = [];
+                for (var _i = 0, _a = propsType.types; _i < _a.length; _i++) {
+                    var t = _a[_i];
+                    propsApparentType.push(getApparentType(t));
+                }
+                return getIntersectionType(propsApparentType);
+            }
+            return getApparentType(propsType);
+        }
+        /**
+         * Get JSX attributes type by trying to resolve openingLikeElement as a stateless function component.
+         * Return only attributes type of successfully resolved call signature.
+         * This function assumes that the caller handled other possible element type of the JSX element (e.g. stateful component)
+         * Unlike tryGetAllJsxStatelessFunctionAttributesType, this function is a default behavior of type-checkers.
+         * @param openingLikeElement a JSX opening-like element to find attributes type
+         * @param elementType a type of the opening-like element. This elementType can't be an union type
+         * @param elemInstanceType an element instance type (the result of newing or invoking this tag)
+         * @param elementClassType a JSX-ElementClass type. This is a result of looking up ElementClass interface in the JSX global
+         */
+        function defaultTryGetJsxStatelessFunctionAttributesType(openingLikeElement, elementType, elemInstanceType, elementClassType) {
+            ts.Debug.assert(!(elementType.flags & 262144 /* Union */));
+            if (!elementClassType || !isTypeAssignableTo(elemInstanceType, elementClassType)) {
+                var jsxStatelessElementType = getJsxStatelessElementTypeAt(openingLikeElement);
+                if (jsxStatelessElementType) {
+                    // We don't call getResolvedSignature here because we have already resolve the type of JSX Element.
+                    var callSignature = getResolvedJsxStatelessFunctionSignature(openingLikeElement, elementType, /*candidatesOutArray*/ undefined);
+                    if (callSignature !== unknownSignature) {
+                        var callReturnType = callSignature && getReturnTypeOfSignature(callSignature);
+                        var paramType = callReturnType && (callSignature.parameters.length === 0 ? emptyObjectType : getTypeOfSymbol(callSignature.parameters[0]));
+                        paramType = getApparentTypeOfJsxPropsType(paramType);
+                        if (callReturnType && isTypeAssignableTo(callReturnType, jsxStatelessElementType)) {
+                            // Intersect in JSX.IntrinsicAttributes if it exists
+                            var intrinsicAttributes = getJsxType(JsxNames.IntrinsicAttributes, openingLikeElement);
+                            if (intrinsicAttributes !== errorType) {
+                                paramType = intersectTypes(intrinsicAttributes, paramType);
+                            }
+                            return paramType;
+                        }
+                    }
+                }
+            }
+            return undefined;
+        }
+        /**
+         * Get JSX attributes type by trying to resolve openingLikeElement as a stateless function component.
+         * Return all attributes type of resolved call signature including candidate signatures.
+         * This function assumes that the caller handled other possible element type of the JSX element.
+         * This function is a behavior used by language service when looking up completion in JSX element.
+         * @param openingLikeElement a JSX opening-like element to find attributes type
+         * @param elementType a type of the opening-like element. This elementType can't be an union type
+         * @param elemInstanceType an element instance type (the result of newing or invoking this tag)
+         * @param elementClassType a JSX-ElementClass type. This is a result of looking up ElementClass interface in the JSX global
+         */
+        function tryGetAllJsxStatelessFunctionAttributesType(openingLikeElement, elementType, elemInstanceType, elementClassType) {
+            ts.Debug.assert(!(elementType.flags & 262144 /* Union */));
+            if (!elementClassType || !isTypeAssignableTo(elemInstanceType, elementClassType)) {
+                // Is this is a stateless function component? See if its single signature's return type is assignable to the JSX Element Type
+                var jsxStatelessElementType = getJsxStatelessElementTypeAt(openingLikeElement);
+                if (jsxStatelessElementType) {
+                    // We don't call getResolvedSignature because here we have already resolve the type of JSX Element.
+                    var candidatesOutArray = [];
+                    getResolvedJsxStatelessFunctionSignature(openingLikeElement, elementType, candidatesOutArray);
+                    var result = void 0;
+                    var allMatchingAttributesType = void 0;
+                    for (var _i = 0, candidatesOutArray_1 = candidatesOutArray; _i < candidatesOutArray_1.length; _i++) {
+                        var candidate = candidatesOutArray_1[_i];
+                        var callReturnType = getReturnTypeOfSignature(candidate);
+                        // TODO: GH#18217: callReturnType should always be defined...
+                        var paramType = callReturnType && (candidate.parameters.length === 0 ? emptyObjectType : getTypeOfSymbol(candidate.parameters[0]));
+                        paramType = getApparentTypeOfJsxPropsType(paramType);
+                        if (callReturnType && isTypeAssignableTo(callReturnType, jsxStatelessElementType)) {
+                            var shouldBeCandidate = true;
+                            for (var _a = 0, _b = openingLikeElement.attributes.properties; _a < _b.length; _a++) {
+                                var attribute = _b[_a];
+                                if (ts.isJsxAttribute(attribute) &&
+                                    isUnhyphenatedJsxName(attribute.name.escapedText) &&
+                                    !getPropertyOfType(paramType, attribute.name.escapedText)) { // TODO: GH#18217
+                                    shouldBeCandidate = false;
+                                    break;
+                                }
+                            }
+                            if (shouldBeCandidate) {
+                                result = intersectTypes(result, paramType);
+                            }
+                            allMatchingAttributesType = intersectTypes(allMatchingAttributesType, paramType);
+                        }
+                    }
+                    // If we can't find any matching, just return everything.
+                    if (!result) {
+                        result = allMatchingAttributesType;
+                    }
+                    // Intersect in JSX.IntrinsicAttributes if it exists
+                    var intrinsicAttributes = getJsxType(JsxNames.IntrinsicAttributes, openingLikeElement);
+                    if (intrinsicAttributes !== errorType) {
+                        result = intersectTypes(intrinsicAttributes, result);
+                    }
+                    return result;
+                }
+            }
+            return undefined;
+        }
+        function getInstantiatedJsxSignatures(openingLikeElement, elementType, reportErrors) {
+            var links = getNodeLinks(openingLikeElement);
+            if (!links.resolvedSignatures) {
+                links.resolvedSignatures = ts.createMap();
+            }
+            var cacheKey = "" + getTypeId(elementType);
+            if (links.resolvedSignatures.get(cacheKey) && links.resolvedSignatures.get(cacheKey) === resolvingSignaturesArray) {
+                return;
+            }
+            else if (links.resolvedSignatures.get(cacheKey)) {
+                return links.resolvedSignatures.get(cacheKey);
+            }
+            links.resolvedSignatures.set(cacheKey, resolvingSignaturesArray);
+            // Resolve the signatures, preferring constructor
+            var signatures = getSignaturesOfType(elementType, 1 /* Construct */);
+            if (signatures.length === 0) {
+                // No construct signatures, try call signatures
+                signatures = getSignaturesOfType(elementType, 0 /* Call */);
+                if (signatures.length === 0) {
+                    // We found no signatures at all, which is an error
+                    if (reportErrors) {
+                        error(openingLikeElement.tagName, ts.Diagnostics.JSX_element_type_0_does_not_have_any_construct_or_call_signatures, ts.getTextOfNode(openingLikeElement.tagName));
+                    }
+                    return;
+                }
+            }
+            // Instantiate in context of source type
+            var results = instantiateJsxSignatures(openingLikeElement, signatures);
+            links.resolvedSignatures.set(cacheKey, results);
+            return results;
+        }
+        /**
+         * Resolve attributes type of the given opening-like element. The attributes type is a type of attributes associated with the given elementType.
+         * For instance:
+         *      declare function Foo(attr: { p1: string}): JSX.Element;
+         *      <Foo p1={10} />;  // This function will try resolve "Foo" and return an attributes type of "Foo" which is "{ p1: string }"
+         *
+         * The function is intended to initially be called from getAttributesTypeFromJsxOpeningLikeElement which already handle JSX-intrinsic-element..
+         * This function will try to resolve custom JSX attributes type in following order: string literal, stateless function, and stateful component
+         *
+         * @param openingLikeElement a non-intrinsic JSXOPeningLikeElement
+         * @param shouldIncludeAllStatelessAttributesType a boolean indicating whether to include all attributes types from all stateless function signature
+         * @param sourceAttributesType Is the attributes type the user passed, and is used to create inferences in the target type if present
+         * @param elementType an instance type of the given opening-like element. If undefined, the function will check type openinglikeElement's tagname.
+         * @param elementClassType a JSX-ElementClass type. This is a result of looking up ElementClass interface in the JSX global (imported from react.d.ts)
+         * @return attributes type if able to resolve the type of node
+         *         anyType if there is no type ElementAttributesProperty or there is an error
+         *         emptyObjectType if there is no "prop" in the element instance type
+         */
+        function resolveCustomJsxElementAttributesType(openingLikeElement, shouldIncludeAllStatelessAttributesType, elementType, elementClassType) {
+            if (elementType.flags & 262144 /* Union */) {
+                var types = elementType.types;
+                return getUnionType(types.map(function (type) {
+                    return resolveCustomJsxElementAttributesType(openingLikeElement, shouldIncludeAllStatelessAttributesType, type, elementClassType);
+                }), 2 /* Subtype */);
+            }
+            // Shortcircuit any
+            if (isTypeAny(elementType)) {
+                return elementType;
+            }
+            // If the elemType is a string type, we have to return anyType to prevent an error downstream as we will try to find construct or call signature of the type
+            else if (elementType.flags & 4 /* String */) {
+                return anyType;
+            }
+            else if (elementType.flags & 64 /* StringLiteral */) {
+                // If the elemType is a stringLiteral type, we can then provide a check to make sure that the string literal type is one of the Jsx intrinsic element type
+                // For example:
+                //      var CustomTag: "h1" = "h1";
+                //      <CustomTag> Hello World </CustomTag>
+                var intrinsicElementsType = getJsxType(JsxNames.IntrinsicElements, openingLikeElement);
+                if (intrinsicElementsType !== errorType) {
+                    var stringLiteralTypeName = elementType.value;
+                    var intrinsicProp = getPropertyOfType(intrinsicElementsType, ts.escapeLeadingUnderscores(stringLiteralTypeName));
+                    if (intrinsicProp) {
+                        return getTypeOfSymbol(intrinsicProp);
+                    }
+                    var indexSignatureType = getIndexTypeOfType(intrinsicElementsType, 0 /* String */);
+                    if (indexSignatureType) {
+                        return indexSignatureType;
+                    }
+                    error(openingLikeElement, ts.Diagnostics.Property_0_does_not_exist_on_type_1, stringLiteralTypeName, "JSX." + JsxNames.IntrinsicElements);
+                }
+                // If we need to report an error, we already done so here. So just return any to prevent any more error downstream
+                return anyType;
+            }
+            // Get the element instance type (the result of newing or invoking this tag)
+            var instantiatedSignatures = getInstantiatedJsxSignatures(openingLikeElement, elementType, /*reportErrors*/ true);
+            if (!ts.length(instantiatedSignatures)) {
+                return errorType;
+            }
+            var elemInstanceType = getUnionType(instantiatedSignatures.map(getReturnTypeOfSignature), 2 /* Subtype */);
+            // If we should include all stateless attributes type, then get all attributes type from all stateless function signature.
+            // Otherwise get only attributes type from the signature picked by choose-overload logic.
+            var statelessAttributesType = shouldIncludeAllStatelessAttributesType ?
+                tryGetAllJsxStatelessFunctionAttributesType(openingLikeElement, elementType, elemInstanceType, elementClassType) :
+                defaultTryGetJsxStatelessFunctionAttributesType(openingLikeElement, elementType, elemInstanceType, elementClassType);
+            if (statelessAttributesType) {
+                return statelessAttributesType;
+            }
+            // Issue an error if this return type isn't assignable to JSX.ElementClass
+            if (elementClassType) {
+                checkTypeRelatedTo(elemInstanceType, elementClassType, assignableRelation, openingLikeElement, ts.Diagnostics.JSX_element_type_0_is_not_a_constructor_function_for_JSX_elements);
+            }
+            var isJs = ts.isInJavaScriptFile(openingLikeElement);
+            return getUnionType(instantiatedSignatures.map(function (sig) { return getJsxPropsTypeFromClassType(sig, isJs, openingLikeElement, /*reportErrors*/ true); }));
+        }
+        /**
+         * Get attributes type of the given intrinsic opening-like Jsx element by resolving the tag name.
+         * The function is intended to be called from a function which has checked that the opening element is an intrinsic element.
+         * @param node an intrinsic JSX opening-like element
+         */
+        function getIntrinsicAttributesTypeFromJsxOpeningLikeElement(node) {
+            ts.Debug.assert(isJsxIntrinsicIdentifier(node.tagName));
+            var links = getNodeLinks(node);
+            if (!links.resolvedJsxElementAttributesType) {
+                var symbol = getIntrinsicTagSymbol(node);
+                if (links.jsxFlags & 1 /* IntrinsicNamedElement */) {
+                    return links.resolvedJsxElementAttributesType = getTypeOfSymbol(symbol);
+                }
+                else if (links.jsxFlags & 2 /* IntrinsicIndexedElement */) {
+                    return links.resolvedJsxElementAttributesType = getIndexInfoOfSymbol(symbol, 0 /* String */).type;
+                }
+                else {
+                    return links.resolvedJsxElementAttributesType = errorType;
+                }
+            }
+            return links.resolvedJsxElementAttributesType;
+        }
+        /**
+         * Get attributes type of the given custom opening-like JSX element.
+         * This function is intended to be called from a caller that handles intrinsic JSX element already.
+         * @param node a custom JSX opening-like element
+         * @param shouldIncludeAllStatelessAttributesType a boolean value used by language service to get all possible attributes type from an overload stateless function component
+         */
+        function getCustomJsxElementAttributesType(node, shouldIncludeAllStatelessAttributesType) {
+            return resolveCustomJsxElementAttributesType(node, shouldIncludeAllStatelessAttributesType, checkExpression(node.tagName), getJsxElementClassTypeAt(node));
+        }
+        /**
+         * Get all possible attributes type, especially from an overload stateless function component, of the given JSX opening-like element.
+         * This function is called by language service (see: completions-tryGetGlobalSymbols).
+         * @param node a JSX opening-like element to get attributes type for
+         */
+        function getAllAttributesTypeFromJsxOpeningLikeElement(node) {
+            if (isJsxIntrinsicIdentifier(node.tagName)) {
+                return getIntrinsicAttributesTypeFromJsxOpeningLikeElement(node);
+            }
+            else {
+                // Because in language service, the given JSX opening-like element may be incomplete and therefore,
+                // we can't resolve to exact signature if the element is a stateless function component so the best thing to do is return all attributes type from all overloads.
+                return getCustomJsxElementAttributesType(node, /*shouldIncludeAllStatelessAttributesType*/ true);
+            }
+        }
+        /**
+         * Get the attributes type, which indicates the attributes that are valid on the given JSXOpeningLikeElement.
+         * @param node a JSXOpeningLikeElement node
+         * @return an attributes type of the given node
+         */
+        function getAttributesTypeFromJsxOpeningLikeElement(node) {
+            if (isJsxIntrinsicIdentifier(node.tagName)) {
+                return getIntrinsicAttributesTypeFromJsxOpeningLikeElement(node);
+            }
+            else {
+                return getCustomJsxElementAttributesType(node, /*shouldIncludeAllStatelessAttributesType*/ false);
+            }
+        }
+        /**
+         * Given a JSX attribute, returns the symbol for the corresponds property
+         * of the element attributes type. Will return unknownSymbol for attributes
+         * that have no matching element attributes type property.
+         */
+        function getJsxAttributePropertySymbol(attrib) {
+            var attributesType = getAttributesTypeFromJsxOpeningLikeElement(attrib.parent.parent);
+            var prop = getPropertyOfType(attributesType, attrib.name.escapedText);
+            return prop || unknownSymbol;
+        }
+        function getJsxElementClassTypeAt(location) {
+            var type = getJsxType(JsxNames.ElementClass, location);
+            if (type === errorType)
+                return undefined;
+            return type;
+        }
+        function getJsxElementTypeAt(location) {
+            return getJsxType(JsxNames.Element, location);
+        }
+        function getJsxStatelessElementTypeAt(location) {
+            var jsxElementType = getJsxElementTypeAt(location);
+            if (jsxElementType) {
+                return getUnionType([jsxElementType, nullType]);
+            }
+        }
+        /**
+         * Returns all the properties of the Jsx.IntrinsicElements interface
+         */
+        function getJsxIntrinsicTagNamesAt(location) {
+            var intrinsics = getJsxType(JsxNames.IntrinsicElements, location);
+            return intrinsics ? getPropertiesOfType(intrinsics) : ts.emptyArray;
+        }
+        function checkJsxPreconditions(errorNode) {
+            // Preconditions for using JSX
+            if ((compilerOptions.jsx || 0 /* None */) === 0 /* None */) {
+                error(errorNode, ts.Diagnostics.Cannot_use_JSX_unless_the_jsx_flag_is_provided);
+            }
+            if (getJsxElementTypeAt(errorNode) === undefined) {
+                if (noImplicitAny) {
+                    error(errorNode, ts.Diagnostics.JSX_element_implicitly_has_type_any_because_the_global_type_JSX_Element_does_not_exist);
+                }
+            }
+        }
+        function checkJsxOpeningLikeElementOrOpeningFragment(node, checkMode) {
+            var isNodeOpeningLikeElement = ts.isJsxOpeningLikeElement(node);
+            if (isNodeOpeningLikeElement) {
+                checkGrammarJsxElement(node);
+            }
+            checkJsxPreconditions(node);
+            // The reactNamespace/jsxFactory's root symbol should be marked as 'used' so we don't incorrectly elide its import.
+            // And if there is no reactNamespace/jsxFactory's symbol in scope when targeting React emit, we should issue an error.
+            var reactRefErr = diagnostics && compilerOptions.jsx === 2 /* React */ ? ts.Diagnostics.Cannot_find_name_0 : undefined;
+            var reactNamespace = getJsxNamespace(node);
+            var reactLocation = isNodeOpeningLikeElement ? node.tagName : node;
+            var reactSym = resolveName(reactLocation, reactNamespace, 67216319 /* Value */, reactRefErr, reactNamespace, /*isUse*/ true);
+            if (reactSym) {
+                // Mark local symbol as referenced here because it might not have been marked
+                // if jsx emit was not react as there wont be error being emitted
+                reactSym.isReferenced = 67108863 /* All */;
+                // If react symbol is alias, mark it as refereced
+                if (reactSym.flags & 2097152 /* Alias */ && !isConstEnumOrConstEnumOnlyModule(resolveAlias(reactSym))) {
+                    markAliasSymbolAsReferenced(reactSym);
+                }
+            }
+            if (isNodeOpeningLikeElement) {
+                checkJsxAttributesAssignableToTagNameAttributes(node, checkMode);
+            }
+            else {
+                checkJsxChildren(node.parent);
+            }
+        }
+        /**
+         * Check if a property with the given name is known anywhere in the given type. In an object type, a property
+         * is considered known if
+         * 1. the object type is empty and the check is for assignability, or
+         * 2. if the object type has index signatures, or
+         * 3. if the property is actually declared in the object type
+         *    (this means that 'toString', for example, is not usually a known property).
+         * 4. In a union or intersection type,
+         *    a property is considered known if it is known in any constituent type.
+         * @param targetType a type to search a given name in
+         * @param name a property name to search
+         * @param isComparingJsxAttributes a boolean flag indicating whether we are searching in JsxAttributesType
+         */
+        function isKnownProperty(targetType, name, isComparingJsxAttributes) {
+            if (targetType.flags & 131072 /* Object */) {
+                var resolved = resolveStructuredTypeMembers(targetType);
+                if (resolved.stringIndexInfo ||
+                    resolved.numberIndexInfo && isNumericLiteralName(name) ||
+                    getPropertyOfObjectType(targetType, name) ||
+                    isComparingJsxAttributes && !isUnhyphenatedJsxName(name)) {
+                    // For JSXAttributes, if the attribute has a hyphenated name, consider that the attribute to be known.
+                    return true;
+                }
+            }
+            else if (targetType.flags & 786432 /* UnionOrIntersection */) {
+                for (var _i = 0, _a = targetType.types; _i < _a.length; _i++) {
+                    var t = _a[_i];
+                    if (isKnownProperty(t, name, isComparingJsxAttributes)) {
+                        return true;
+                    }
+                }
+            }
+            return false;
+        }
+        /**
+         * Check whether the given attributes of JSX opening-like element is assignable to the tagName attributes.
+         *      Get the attributes type of the opening-like element through resolving the tagName, "target attributes"
+         *      Check assignablity between given attributes property, "source attributes", and the "target attributes"
+         * @param openingLikeElement an opening-like JSX element to check its JSXAttributes
+         */
+        function checkJsxAttributesAssignableToTagNameAttributes(openingLikeElement, checkMode) {
+            // The function involves following steps:
+            //      1. Figure out expected attributes type by resolving tagName of the JSX opening-like element, targetAttributesType.
+            //         During these steps, we will try to resolve the tagName as intrinsic name, stateless function, stateful component (in the order)
+            //      2. Solved JSX attributes type given by users, sourceAttributesType, which is by resolving "attributes" property of the JSX opening-like element.
+            //      3. Check if the two are assignable to each other
+            // targetAttributesType is a type of an attribute from resolving tagName of an opening-like JSX element.
+            var targetAttributesType = isJsxIntrinsicIdentifier(openingLikeElement.tagName) ?
+                getIntrinsicAttributesTypeFromJsxOpeningLikeElement(openingLikeElement) :
+                getCustomJsxElementAttributesType(openingLikeElement, /*shouldIncludeAllStatelessAttributesType*/ false);
+            // sourceAttributesType is a type of an attributes properties.
+            // i.e <div attr1={10} attr2="string" />
+            //     attr1 and attr2 are treated as JSXAttributes attached in the JsxOpeningLikeElement as "attributes".
+            var sourceAttributesType = createJsxAttributesTypeFromAttributesProperty(openingLikeElement, checkMode);
+            // Check if sourceAttributesType assignable to targetAttributesType though this check will allow excess properties
+            var isSourceAttributeTypeAssignableToTarget = isTypeAssignableTo(sourceAttributesType, targetAttributesType);
+            // After we check for assignability, we will do another pass to check that all explicitly specified attributes have correct name corresponding in targetAttributeType.
+            // This will allow excess properties in spread type as it is very common pattern to spread outer attributes into React component in its render method.
+            if (isSourceAttributeTypeAssignableToTarget && !isTypeAny(sourceAttributesType) && !isTypeAny(targetAttributesType)) {
+                for (var _i = 0, _a = openingLikeElement.attributes.properties; _i < _a.length; _i++) {
+                    var attribute = _a[_i];
+                    if (!ts.isJsxAttribute(attribute)) {
+                        continue;
+                    }
+                    var attrName = attribute.name;
+                    var isNotIgnoredJsxProperty = (isUnhyphenatedJsxName(ts.idText(attrName)) || !!(getPropertyOfType(targetAttributesType, attrName.escapedText)));
+                    if (isNotIgnoredJsxProperty && !isKnownProperty(targetAttributesType, attrName.escapedText, /*isComparingJsxAttributes*/ true)) {
+                        error(attribute, ts.Diagnostics.Property_0_does_not_exist_on_type_1, ts.idText(attrName), typeToString(targetAttributesType));
+                        // We break here so that errors won't be cascading
+                        break;
+                    }
+                }
+            }
+            else if (!isSourceAttributeTypeAssignableToTarget) {
+                // Assignability failure - check each prop individually, and if that fails, fall back on the bad error span
+                if (ts.length(openingLikeElement.attributes.properties)) {
+                    var reportedError = false;
+                    var _loop_8 = function (prop) {
+                        if (ts.isJsxSpreadAttribute(prop))
+                            return "continue";
+                        var name = ts.idText(prop.name);
+                        var sourcePropType = getIndexedAccessType(sourceAttributesType, getLiteralType(name));
+                        var targetPropType = getIndexedAccessType(targetAttributesType, getLiteralType(name));
+                        var rootChain = function () { return ts.chainDiagnosticMessages(
+                        /*details*/ undefined, ts.Diagnostics.Types_of_property_0_are_incompatible, name); };
+                        if (!checkTypeAssignableTo(sourcePropType, targetPropType, prop, /*headMessage*/ undefined, rootChain)) {
+                            reportedError = true;
+                        }
+                    };
+                    for (var _b = 0, _c = openingLikeElement.attributes.properties; _b < _c.length; _b++) {
+                        var prop = _c[_b];
+                        _loop_8(prop);
+                    }
+                    if (reportedError) {
+                        return;
+                    }
+                }
+                // Report fallback error on just the component name
+                checkTypeAssignableTo(sourceAttributesType, targetAttributesType, openingLikeElement.tagName);
+            }
+        }
+        function checkJsxExpression(node, checkMode) {
+            if (node.expression) {
+                var type = checkExpression(node.expression, checkMode);
+                if (node.dotDotDotToken && type !== anyType && !isArrayType(type)) {
+                    error(node, ts.Diagnostics.JSX_spread_child_must_be_an_array_type);
+                }
+                return type;
+            }
+            else {
+                return errorType;
+            }
+        }
+        // If a symbol is a synthesized symbol with no value declaration, we assume it is a property. Example of this are the synthesized
+        // '.prototype' property as well as synthesized tuple index properties.
+        function getDeclarationKindFromSymbol(s) {
+            return s.valueDeclaration ? s.valueDeclaration.kind : 152 /* PropertyDeclaration */;
+        }
+        function getDeclarationNodeFlagsFromSymbol(s) {
+            return s.valueDeclaration ? ts.getCombinedNodeFlags(s.valueDeclaration) : 0;
+        }
+        /**
+         * Return whether this symbol is a member of a prototype somewhere
+         * Note that this is not tracked well within the compiler, so the answer may be incorrect.
+         */
+        function isPrototypeProperty(symbol) {
+            if (symbol.flags & 8192 /* Method */ || ts.getCheckFlags(symbol) & 4 /* SyntheticMethod */) {
+                return true;
+            }
+            if (ts.isInJavaScriptFile(symbol.valueDeclaration)) {
+                var parent = symbol.valueDeclaration.parent;
+                return parent && ts.isBinaryExpression(parent) &&
+                    ts.getSpecialPropertyAssignmentKind(parent) === 3 /* PrototypeProperty */;
+            }
+        }
+        /**
+         * Check whether the requested property access is valid.
+         * Returns true if node is a valid property access, and false otherwise.
+         * @param node The node to be checked.
+         * @param left The left hand side of the property access (e.g.: the super in `super.foo`).
+         * @param type The type of left.
+         * @param prop The symbol for the right hand side of the property access.
+         */
+        function checkPropertyAccessibility(node, left, type, prop) {
+            var flags = ts.getDeclarationModifierFlagsFromSymbol(prop);
+            var errorNode = node.kind === 185 /* PropertyAccessExpression */ || node.kind === 232 /* VariableDeclaration */ ?
+                node.name :
+                node.kind === 179 /* ImportType */ ?
+                    node :
+                    node.right;
+            if (ts.getCheckFlags(prop) & 256 /* ContainsPrivate */) {
+                // Synthetic property with private constituent property
+                error(errorNode, ts.Diagnostics.Property_0_has_conflicting_declarations_and_is_inaccessible_in_type_1, symbolToString(prop), typeToString(type));
+                return false;
+            }
+            if (left.kind === 97 /* SuperKeyword */) {
+                // TS 1.0 spec (April 2014): 4.8.2
+                // - In a constructor, instance member function, instance member accessor, or
+                //   instance member variable initializer where this references a derived class instance,
+                //   a super property access is permitted and must specify a public instance member function of the base class.
+                // - In a static member function or static member accessor
+                //   where this references the constructor function object of a derived class,
+                //   a super property access is permitted and must specify a public static member function of the base class.
+                if (languageVersion < 2 /* ES2015 */) {
+                    if (symbolHasNonMethodDeclaration(prop)) {
+                        error(errorNode, ts.Diagnostics.Only_public_and_protected_methods_of_the_base_class_are_accessible_via_the_super_keyword);
+                        return false;
+                    }
+                }
+                if (flags & 128 /* Abstract */) {
+                    // A method cannot be accessed in a super property access if the method is abstract.
+                    // This error could mask a private property access error. But, a member
+                    // cannot simultaneously be private and abstract, so this will trigger an
+                    // additional error elsewhere.
+                    error(errorNode, ts.Diagnostics.Abstract_method_0_in_class_1_cannot_be_accessed_via_super_expression, symbolToString(prop), typeToString(getDeclaringClass(prop)));
+                    return false;
+                }
+            }
+            // Referencing abstract properties within their own constructors is not allowed
+            if ((flags & 128 /* Abstract */) && ts.isThisProperty(node) && symbolHasNonMethodDeclaration(prop)) {
+                var declaringClassDeclaration = ts.getClassLikeDeclarationOfSymbol(getParentOfSymbol(prop));
+                if (declaringClassDeclaration && isNodeWithinConstructorOfClass(node, declaringClassDeclaration)) {
+                    error(errorNode, ts.Diagnostics.Abstract_property_0_in_class_1_cannot_be_accessed_in_the_constructor, symbolToString(prop), ts.getTextOfIdentifierOrLiteral(declaringClassDeclaration.name)); // TODO: GH#18217
+                    return false;
+                }
+            }
+            // Public properties are otherwise accessible.
+            if (!(flags & 24 /* NonPublicAccessibilityModifier */)) {
+                return true;
+            }
+            // Property is known to be private or protected at this point
+            // Private property is accessible if the property is within the declaring class
+            if (flags & 8 /* Private */) {
+                var declaringClassDeclaration = ts.getClassLikeDeclarationOfSymbol(getParentOfSymbol(prop));
+                if (!isNodeWithinClass(node, declaringClassDeclaration)) {
+                    error(errorNode, ts.Diagnostics.Property_0_is_private_and_only_accessible_within_class_1, symbolToString(prop), typeToString(getDeclaringClass(prop)));
+                    return false;
+                }
+                return true;
+            }
+            // Property is known to be protected at this point
+            // All protected properties of a supertype are accessible in a super access
+            if (left.kind === 97 /* SuperKeyword */) {
+                return true;
+            }
+            // Find the first enclosing class that has the declaring classes of the protected constituents
+            // of the property as base classes
+            var enclosingClass = forEachEnclosingClass(node, function (enclosingDeclaration) {
+                var enclosingClass = getDeclaredTypeOfSymbol(getSymbolOfNode(enclosingDeclaration));
+                return isClassDerivedFromDeclaringClasses(enclosingClass, prop) ? enclosingClass : undefined;
+            });
+            // A protected property is accessible if the property is within the declaring class or classes derived from it
+            if (!enclosingClass) {
+                // allow PropertyAccessibility if context is in function with this parameter
+                // static member access is disallow
+                var thisParameter = void 0;
+                if (flags & 32 /* Static */ || !(thisParameter = getThisParameterFromNodeContext(node)) || !thisParameter.type) {
+                    error(errorNode, ts.Diagnostics.Property_0_is_protected_and_only_accessible_within_class_1_and_its_subclasses, symbolToString(prop), typeToString(getDeclaringClass(prop) || type));
+                    return false;
+                }
+                var thisType = getTypeFromTypeNode(thisParameter.type);
+                enclosingClass = ((thisType.flags & 65536 /* TypeParameter */) ? getConstraintFromTypeParameter(thisType) : thisType);
+            }
+            // No further restrictions for static properties
+            if (flags & 32 /* Static */) {
+                return true;
+            }
+            if (type.flags & 65536 /* TypeParameter */) {
+                // get the original type -- represented as the type constraint of the 'this' type
+                type = type.isThisType ? getConstraintOfTypeParameter(type) : getBaseConstraintOfType(type); // TODO: GH#18217 Use a different variable that's allowed to be undefined
+            }
+            if (!type || !hasBaseType(type, enclosingClass)) {
+                error(errorNode, ts.Diagnostics.Property_0_is_protected_and_only_accessible_through_an_instance_of_class_1, symbolToString(prop), typeToString(enclosingClass));
+                return false;
+            }
+            return true;
+        }
+        function getThisParameterFromNodeContext(node) {
+            var thisContainer = ts.getThisContainer(node, /* includeArrowFunctions */ false);
+            return thisContainer && ts.isFunctionLike(thisContainer) ? ts.getThisParameter(thisContainer) : undefined;
+        }
+        function symbolHasNonMethodDeclaration(symbol) {
+            return forEachProperty(symbol, function (prop) {
+                var propKind = getDeclarationKindFromSymbol(prop);
+                return propKind !== 154 /* MethodDeclaration */ && propKind !== 153 /* MethodSignature */;
+            });
+        }
+        function checkNonNullExpression(node, nullDiagnostic, undefinedDiagnostic, nullOrUndefinedDiagnostic) {
+            return checkNonNullType(checkExpression(node), node, nullDiagnostic, undefinedDiagnostic, nullOrUndefinedDiagnostic);
+        }
+        function checkNonNullType(type, node, nullDiagnostic, undefinedDiagnostic, nullOrUndefinedDiagnostic) {
+            if (type.flags & 2 /* Unknown */) {
+                error(node, ts.Diagnostics.Object_is_of_type_unknown);
+                return errorType;
+            }
+            var kind = (strictNullChecks ? getFalsyFlags(type) : type.flags) & 24576 /* Nullable */;
+            if (kind) {
+                error(node, kind & 8192 /* Undefined */ ? kind & 16384 /* Null */ ?
+                    (nullOrUndefinedDiagnostic || ts.Diagnostics.Object_is_possibly_null_or_undefined) :
+                    (undefinedDiagnostic || ts.Diagnostics.Object_is_possibly_undefined) :
+                    (nullDiagnostic || ts.Diagnostics.Object_is_possibly_null));
+                var t = getNonNullableType(type);
+                return t.flags & (24576 /* Nullable */ | 32768 /* Never */) ? errorType : t;
+            }
+            return type;
+        }
+        function checkPropertyAccessExpression(node) {
+            return checkPropertyAccessExpressionOrQualifiedName(node, node.expression, node.name);
+        }
+        function checkQualifiedName(node) {
+            return checkPropertyAccessExpressionOrQualifiedName(node, node.left, node.right);
+        }
+        function checkPropertyAccessExpressionOrQualifiedName(node, left, right) {
+            var propType;
+            var leftType = checkNonNullExpression(left);
+            var parentSymbol = getNodeLinks(left).resolvedSymbol;
+            var apparentType = getApparentType(getWidenedType(leftType));
+            if (isTypeAny(apparentType) || apparentType === silentNeverType) {
+                if (ts.isIdentifier(left) && parentSymbol) {
+                    markAliasReferenced(parentSymbol, node);
+                }
+                return apparentType;
+            }
+            var assignmentKind = ts.getAssignmentTargetKind(node);
+            var prop = getPropertyOfType(apparentType, right.escapedText);
+            if (ts.isIdentifier(left) && parentSymbol && !(prop && isConstEnumOrConstEnumOnlyModule(prop))) {
+                markAliasReferenced(parentSymbol, node);
+            }
+            if (!prop) {
+                var indexInfo = getIndexInfoOfType(apparentType, 0 /* String */);
+                if (!(indexInfo && indexInfo.type)) {
+                    if (right.escapedText && !checkAndReportErrorForExtendingInterface(node)) {
+                        reportNonexistentProperty(right, leftType.flags & 65536 /* TypeParameter */ && leftType.isThisType ? apparentType : leftType);
+                    }
+                    return errorType;
+                }
+                if (indexInfo.isReadonly && (ts.isAssignmentTarget(node) || ts.isDeleteTarget(node))) {
+                    error(node, ts.Diagnostics.Index_signature_in_type_0_only_permits_reading, typeToString(apparentType));
+                }
+                propType = indexInfo.type;
+            }
+            else {
+                checkPropertyNotUsedBeforeDeclaration(prop, node, right);
+                markPropertyAsReferenced(prop, node, left.kind === 99 /* ThisKeyword */);
+                getNodeLinks(node).resolvedSymbol = prop;
+                checkPropertyAccessibility(node, left, apparentType, prop);
+                if (assignmentKind) {
+                    if (isReferenceToReadonlyEntity(node, prop) || isReferenceThroughNamespaceImport(node)) {
+                        error(right, ts.Diagnostics.Cannot_assign_to_0_because_it_is_a_constant_or_a_read_only_property, ts.idText(right));
+                        return errorType;
+                    }
+                }
+                propType = getConstraintForLocation(getTypeOfSymbol(prop), node);
+            }
+            // Only compute control flow type if this is a property access expression that isn't an
+            // assignment target, and the referenced property was declared as a variable, property,
+            // accessor, or optional method.
+            if (node.kind !== 185 /* PropertyAccessExpression */ ||
+                assignmentKind === 1 /* Definite */ ||
+                prop && !(prop.flags & (3 /* Variable */ | 4 /* Property */ | 98304 /* Accessor */)) && !(prop.flags & 8192 /* Method */ && propType.flags & 262144 /* Union */)) {
+                return propType;
+            }
+            // If strict null checks and strict property initialization checks are enabled, if we have
+            // a this.xxx property access, if the property is an instance property without an initializer,
+            // and if we are in a constructor of the same class as the property declaration, assume that
+            // the property is uninitialized at the top of the control flow.
+            var assumeUninitialized = false;
+            if (strictNullChecks && strictPropertyInitialization && left.kind === 99 /* ThisKeyword */) {
+                var declaration = prop && prop.valueDeclaration;
+                if (declaration && isInstancePropertyWithoutInitializer(declaration)) {
+                    var flowContainer = getControlFlowContainer(node);
+                    if (flowContainer.kind === 155 /* Constructor */ && flowContainer.parent === declaration.parent) {
+                        assumeUninitialized = true;
+                    }
+                }
+            }
+            var flowType = getFlowTypeOfReference(node, propType, assumeUninitialized ? getOptionalType(propType) : propType);
+            if (assumeUninitialized && !(getFalsyFlags(propType) & 8192 /* Undefined */) && getFalsyFlags(flowType) & 8192 /* Undefined */) {
+                error(right, ts.Diagnostics.Property_0_is_used_before_being_assigned, symbolToString(prop)); // TODO: GH#18217
+                // Return the declared type to reduce follow-on errors
+                return propType;
+            }
+            return assignmentKind ? getBaseTypeOfLiteralType(flowType) : flowType;
+        }
+        function checkPropertyNotUsedBeforeDeclaration(prop, node, right) {
+            var valueDeclaration = prop.valueDeclaration;
+            if (!valueDeclaration) {
+                return;
+            }
+            if (isInPropertyInitializer(node) &&
+                !isBlockScopedNameDeclaredBeforeUse(valueDeclaration, right)
+                && !isPropertyDeclaredInAncestorClass(prop)) {
+                error(right, ts.Diagnostics.Block_scoped_variable_0_used_before_its_declaration, ts.idText(right));
+            }
+            else if (valueDeclaration.kind === 235 /* ClassDeclaration */ &&
+                node.parent.kind !== 162 /* TypeReference */ &&
+                !(valueDeclaration.flags & 4194304 /* Ambient */) &&
+                !isBlockScopedNameDeclaredBeforeUse(valueDeclaration, right)) {
+                error(right, ts.Diagnostics.Class_0_used_before_its_declaration, ts.idText(right));
+            }
+        }
+        function isInPropertyInitializer(node) {
+            return !!ts.findAncestor(node, function (node) {
+                switch (node.kind) {
+                    case 152 /* PropertyDeclaration */:
+                        return true;
+                    case 270 /* PropertyAssignment */:
+                        // We might be in `a = { b: this.b }`, so keep looking. See `tests/cases/compiler/useBeforeDeclaration_propertyAssignment.ts`.
+                        return false;
+                    default:
+                        return ts.isExpressionNode(node) ? false : "quit";
+                }
+            });
+        }
+        /**
+         * It's possible that "prop.valueDeclaration" is a local declaration, but the property was also declared in a superclass.
+         * In that case we won't consider it used before its declaration, because it gets its value from the superclass' declaration.
+         */
+        function isPropertyDeclaredInAncestorClass(prop) {
+            if (!(prop.parent.flags & 32 /* Class */)) {
+                return false;
+            }
+            var classType = getTypeOfSymbol(prop.parent);
+            while (true) {
+                classType = classType.symbol && getSuperClass(classType);
+                if (!classType) {
+                    return false;
+                }
+                var superProperty = getPropertyOfType(classType, prop.escapedName);
+                if (superProperty && superProperty.valueDeclaration) {
+                    return true;
+                }
+            }
+        }
+        function getSuperClass(classType) {
+            var x = getBaseTypes(classType);
+            if (x.length === 0) {
+                return undefined;
+            }
+            return getIntersectionType(x);
+        }
+        function reportNonexistentProperty(propNode, containingType) {
+            var errorInfo;
+            if (containingType.flags & 262144 /* Union */ && !(containingType.flags & 32764 /* Primitive */)) {
+                for (var _i = 0, _a = containingType.types; _i < _a.length; _i++) {
+                    var subtype = _a[_i];
+                    if (!getPropertyOfType(subtype, propNode.escapedText)) {
+                        errorInfo = ts.chainDiagnosticMessages(errorInfo, ts.Diagnostics.Property_0_does_not_exist_on_type_1, ts.declarationNameToString(propNode), typeToString(subtype));
+                        break;
+                    }
+                }
+            }
+            var promisedType = getPromisedTypeOfPromise(containingType);
+            if (promisedType && getPropertyOfType(promisedType, propNode.escapedText)) {
+                errorInfo = ts.chainDiagnosticMessages(errorInfo, ts.Diagnostics.Property_0_does_not_exist_on_type_1_Did_you_forget_to_use_await, ts.declarationNameToString(propNode), typeToString(containingType));
+            }
+            else {
+                var suggestion = getSuggestionForNonexistentProperty(propNode, containingType);
+                if (suggestion !== undefined) {
+                    errorInfo = ts.chainDiagnosticMessages(errorInfo, ts.Diagnostics.Property_0_does_not_exist_on_type_1_Did_you_mean_2, ts.declarationNameToString(propNode), typeToString(containingType), suggestion);
+                }
+                else {
+                    errorInfo = ts.chainDiagnosticMessages(errorInfo, ts.Diagnostics.Property_0_does_not_exist_on_type_1, ts.declarationNameToString(propNode), typeToString(containingType));
+                }
+            }
+            diagnostics.add(ts.createDiagnosticForNodeFromMessageChain(propNode, errorInfo));
+        }
+        function getSuggestionForNonexistentProperty(node, containingType) {
+            var suggestion = getSpellingSuggestionForName(ts.idText(node), getPropertiesOfType(containingType), 67216319 /* Value */);
+            return suggestion && ts.symbolName(suggestion);
+        }
+        function getSuggestionForNonexistentSymbol(location, outerName, meaning) {
+            ts.Debug.assert(outerName !== undefined, "outername should always be defined");
+            var result = resolveNameHelper(location, outerName, meaning, /*nameNotFoundMessage*/ undefined, outerName, /*isUse*/ false, /*excludeGlobals*/ false, function (symbols, name, meaning) {
+                ts.Debug.assertEqual(outerName, name, "name should equal outerName");
+                var symbol = getSymbol(symbols, name, meaning);
+                // Sometimes the symbol is found when location is a return type of a function: `typeof x` and `x` is declared in the body of the function
+                // So the table *contains* `x` but `x` isn't actually in scope.
+                // However, resolveNameHelper will continue and call this callback again, so we'll eventually get a correct suggestion.
+                return symbol || getSpellingSuggestionForName(ts.unescapeLeadingUnderscores(name), ts.arrayFrom(symbols.values()), meaning);
+            });
+            return result && ts.symbolName(result);
+        }
+        function getSuggestionForNonexistentModule(name, targetModule) {
+            var suggestion = targetModule.exports && getSpellingSuggestionForName(ts.idText(name), getExportsOfModuleAsArray(targetModule), 2623475 /* ModuleMember */);
+            return suggestion && ts.symbolName(suggestion);
+        }
+        /**
+         * Given a name and a list of symbols whose names are *not* equal to the name, return a spelling suggestion if there is one that is close enough.
+         * Names less than length 3 only check for case-insensitive equality, not levenshtein distance.
+         *
+         * If there is a candidate that's the same except for case, return that.
+         * If there is a candidate that's within one edit of the name, return that.
+         * Otherwise, return the candidate with the smallest Levenshtein distance,
+         *    except for candidates:
+         *      * With no name
+         *      * Whose meaning doesn't match the `meaning` parameter.
+         *      * Whose length differs from the target name by more than 0.34 of the length of the name.
+         *      * Whose levenshtein distance is more than 0.4 of the length of the name
+         *        (0.4 allows 1 substitution/transposition for every 5 characters,
+         *         and 1 insertion/deletion at 3 characters)
+         */
+        function getSpellingSuggestionForName(name, symbols, meaning) {
+            return ts.getSpellingSuggestion(name, symbols, getCandidateName);
+            function getCandidateName(candidate) {
+                var candidateName = ts.symbolName(candidate);
+                return !ts.startsWith(candidateName, "\"") && candidate.flags & meaning ? candidateName : undefined;
+            }
+        }
+        function markPropertyAsReferenced(prop, nodeForCheckWriteOnly, isThisAccess) {
+            if (!prop || !(prop.flags & 106500 /* ClassMember */) || !prop.valueDeclaration || !ts.hasModifier(prop.valueDeclaration, 8 /* Private */)) {
+                return;
+            }
+            if (nodeForCheckWriteOnly && ts.isWriteOnlyAccess(nodeForCheckWriteOnly) && !(prop.flags & 65536 /* SetAccessor */ && !(prop.flags & 32768 /* GetAccessor */))) {
+                return;
+            }
+            if (isThisAccess) {
+                // Find any FunctionLikeDeclaration because those create a new 'this' binding. But this should only matter for methods (or getters/setters).
+                var containingMethod = ts.findAncestor(nodeForCheckWriteOnly, ts.isFunctionLikeDeclaration);
+                if (containingMethod && containingMethod.symbol === prop) {
+                    return;
+                }
+            }
+            (ts.getCheckFlags(prop) & 1 /* Instantiated */ ? getSymbolLinks(prop).target : prop).isReferenced = 67108863 /* All */;
+        }
+        function isValidPropertyAccess(node, propertyName) {
+            switch (node.kind) {
+                case 185 /* PropertyAccessExpression */:
+                    return isValidPropertyAccessWithType(node, node.expression, propertyName, getWidenedType(checkExpression(node.expression)));
+                case 146 /* QualifiedName */:
+                    return isValidPropertyAccessWithType(node, node.left, propertyName, getWidenedType(checkExpression(node.left)));
+                case 179 /* ImportType */:
+                    return isValidPropertyAccessWithType(node, node, propertyName, getTypeFromTypeNode(node));
+            }
+        }
+        function isValidPropertyAccessForCompletions(node, type, property) {
+            return isValidPropertyAccessWithType(node, node.kind === 179 /* ImportType */ ? node : node.expression, property.escapedName, type)
+                && (!(property.flags & 8192 /* Method */) || isValidMethodAccess(property, type));
+        }
+        function isValidMethodAccess(method, actualThisType) {
+            var propType = getTypeOfPropertyOfType(actualThisType, method.escapedName);
+            var signatures = getSignaturesOfType(getNonNullableType(propType), 0 /* Call */);
+            ts.Debug.assert(signatures.length !== 0);
+            return signatures.some(function (sig) {
+                var signatureThisType = getThisTypeOfSignature(sig);
+                return !signatureThisType || isTypeAssignableTo(actualThisType, getInstantiatedSignatureThisType(sig, signatureThisType, actualThisType));
+            });
+        }
+        function getInstantiatedSignatureThisType(sig, signatureThisType, actualThisType) {
+            if (!sig.typeParameters) {
+                return signatureThisType;
+            }
+            var context = createInferenceContext(sig.typeParameters, sig, 0 /* None */);
+            inferTypes(context.inferences, actualThisType, signatureThisType);
+            return instantiateType(signatureThisType, createSignatureTypeMapper(sig, getInferredTypes(context)));
+        }
+        function isValidPropertyAccessWithType(node, left, propertyName, type) {
+            if (type === errorType || isTypeAny(type)) {
+                return true;
+            }
+            var prop = getPropertyOfType(type, propertyName);
+            return prop ? checkPropertyAccessibility(node, left, type, prop)
+                // In js files properties of unions are allowed in completion
+                : ts.isInJavaScriptFile(node) && (type.flags & 262144 /* Union */) !== 0 && type.types.some(function (elementType) { return isValidPropertyAccessWithType(node, left, propertyName, elementType); });
+        }
+        /**
+         * Return the symbol of the for-in variable declared or referenced by the given for-in statement.
+         */
+        function getForInVariableSymbol(node) {
+            var initializer = node.initializer;
+            if (initializer.kind === 233 /* VariableDeclarationList */) {
+                var variable = initializer.declarations[0];
+                if (variable && !ts.isBindingPattern(variable.name)) {
+                    return getSymbolOfNode(variable);
+                }
+            }
+            else if (initializer.kind === 71 /* Identifier */) {
+                return getResolvedSymbol(initializer);
+            }
+            return undefined;
+        }
+        /**
+         * Return true if the given type is considered to have numeric property names.
+         */
+        function hasNumericPropertyNames(type) {
+            return getIndexTypeOfType(type, 1 /* Number */) && !getIndexTypeOfType(type, 0 /* String */);
+        }
+        /**
+         * Return true if given node is an expression consisting of an identifier (possibly parenthesized)
+         * that references a for-in variable for an object with numeric property names.
+         */
+        function isForInVariableForNumericPropertyNames(expr) {
+            var e = ts.skipParentheses(expr);
+            if (e.kind === 71 /* Identifier */) {
+                var symbol = getResolvedSymbol(e);
+                if (symbol.flags & 3 /* Variable */) {
+                    var child = expr;
+                    var node = expr.parent;
+                    while (node) {
+                        if (node.kind === 221 /* ForInStatement */ &&
+                            child === node.statement &&
+                            getForInVariableSymbol(node) === symbol &&
+                            hasNumericPropertyNames(getTypeOfExpression(node.expression))) {
+                            return true;
+                        }
+                        child = node;
+                        node = node.parent;
+                    }
+                }
+            }
+            return false;
+        }
+        function checkIndexedAccess(node) {
+            var objectType = checkNonNullExpression(node.expression);
+            var indexExpression = node.argumentExpression;
+            if (!indexExpression) {
+                var sourceFile = ts.getSourceFileOfNode(node);
+                if (node.parent.kind === 188 /* NewExpression */ && node.parent.expression === node) {
+                    var start = ts.skipTrivia(sourceFile.text, node.expression.end);
+                    var end = node.end;
+                    grammarErrorAtPos(sourceFile, start, end - start, ts.Diagnostics.new_T_cannot_be_used_to_create_an_array_Use_new_Array_T_instead);
+                }
+                else {
+                    var start = node.end - "]".length;
+                    var end = node.end;
+                    grammarErrorAtPos(sourceFile, start, end - start, ts.Diagnostics.Expression_expected);
+                }
+                return errorType;
+            }
+            var indexType = isForInVariableForNumericPropertyNames(indexExpression) ? numberType : checkExpression(indexExpression);
+            if (objectType === errorType || objectType === silentNeverType) {
+                return objectType;
+            }
+            if (isConstEnumObjectType(objectType) && indexExpression.kind !== 9 /* StringLiteral */) {
+                error(indexExpression, ts.Diagnostics.A_const_enum_member_can_only_be_accessed_using_a_string_literal);
+                return errorType;
+            }
+            return checkIndexedAccessIndexType(getIndexedAccessType(objectType, indexType, node), node);
+        }
+        function checkThatExpressionIsProperSymbolReference(expression, expressionType, reportError) {
+            if (expressionType === errorType) {
+                // There is already an error, so no need to report one.
+                return false;
+            }
+            if (!ts.isWellKnownSymbolSyntactically(expression)) {
+                return false;
+            }
+            // Make sure the property type is the primitive symbol type
+            if ((expressionType.flags & 3072 /* ESSymbolLike */) === 0) {
+                if (reportError) {
+                    error(expression, ts.Diagnostics.A_computed_property_name_of_the_form_0_must_be_of_type_symbol, ts.getTextOfNode(expression));
+                }
+                return false;
+            }
+            // The name is Symbol.<someName>, so make sure Symbol actually resolves to the
+            // global Symbol object
+            var leftHandSide = expression.expression;
+            var leftHandSideSymbol = getResolvedSymbol(leftHandSide);
+            if (!leftHandSideSymbol) {
+                return false;
+            }
+            var globalESSymbol = getGlobalESSymbolConstructorSymbol(/*reportErrors*/ true);
+            if (!globalESSymbol) {
+                // Already errored when we tried to look up the symbol
+                return false;
+            }
+            if (leftHandSideSymbol !== globalESSymbol) {
+                if (reportError) {
+                    error(leftHandSide, ts.Diagnostics.Symbol_reference_does_not_refer_to_the_global_Symbol_constructor_object);
+                }
+                return false;
+            }
+            return true;
+        }
+        function callLikeExpressionMayHaveTypeArguments(node) {
+            // TODO: Also include tagged templates (https://github.com/Microsoft/TypeScript/issues/11947)
+            return ts.isCallOrNewExpression(node);
+        }
+        function resolveUntypedCall(node) {
+            if (callLikeExpressionMayHaveTypeArguments(node)) {
+                // Check type arguments even though we will give an error that untyped calls may not accept type arguments.
+                // This gets us diagnostics for the type arguments and marks them as referenced.
+                ts.forEach(node.typeArguments, checkSourceElement);
+            }
+            if (node.kind === 189 /* TaggedTemplateExpression */) {
+                checkExpression(node.template);
+            }
+            else if (node.kind !== 150 /* Decorator */) {
+                ts.forEach(node.arguments, function (argument) {
+                    checkExpression(argument);
+                });
+            }
+            return anySignature;
+        }
+        function resolveErrorCall(node) {
+            resolveUntypedCall(node);
+            return unknownSignature;
+        }
+        // Re-order candidate signatures into the result array. Assumes the result array to be empty.
+        // The candidate list orders groups in reverse, but within a group signatures are kept in declaration order
+        // A nit here is that we reorder only signatures that belong to the same symbol,
+        // so order how inherited signatures are processed is still preserved.
+        // interface A { (x: string): void }
+        // interface B extends A { (x: 'foo'): string }
+        // const b: B;
+        // b('foo') // <- here overloads should be processed as [(x:'foo'): string, (x: string): void]
+        function reorderCandidates(signatures, result) {
+            var lastParent;
+            var lastSymbol;
+            var cutoffIndex = 0;
+            var index;
+            var specializedIndex = -1;
+            var spliceIndex;
+            ts.Debug.assert(!result.length);
+            for (var _i = 0, signatures_4 = signatures; _i < signatures_4.length; _i++) {
+                var signature = signatures_4[_i];
+                var symbol = signature.declaration && getSymbolOfNode(signature.declaration);
+                var parent = signature.declaration && signature.declaration.parent;
+                if (!lastSymbol || symbol === lastSymbol) {
+                    if (lastParent && parent === lastParent) {
+                        index = index + 1;
+                    }
+                    else {
+                        lastParent = parent;
+                        index = cutoffIndex;
+                    }
+                }
+                else {
+                    // current declaration belongs to a different symbol
+                    // set cutoffIndex so re-orderings in the future won't change result set from 0 to cutoffIndex
+                    index = cutoffIndex = result.length;
+                    lastParent = parent;
+                }
+                lastSymbol = symbol;
+                // specialized signatures always need to be placed before non-specialized signatures regardless
+                // of the cutoff position; see GH#1133
+                if (signature.hasLiteralTypes) {
+                    specializedIndex++;
+                    spliceIndex = specializedIndex;
+                    // The cutoff index always needs to be greater than or equal to the specialized signature index
+                    // in order to prevent non-specialized signatures from being added before a specialized
+                    // signature.
+                    cutoffIndex++;
+                }
+                else {
+                    spliceIndex = index;
+                }
+                result.splice(spliceIndex, 0, signature);
+            }
+        }
+        function getSpreadArgumentIndex(args) {
+            for (var i = 0; i < args.length; i++) {
+                var arg = args[i];
+                if (arg && arg.kind === 204 /* SpreadElement */) {
+                    return i;
+                }
+            }
+            return -1;
+        }
+        function hasCorrectArity(node, args, signature, signatureHelpTrailingComma) {
+            if (signatureHelpTrailingComma === void 0) { signatureHelpTrailingComma = false; }
+            var argCount; // Apparent number of arguments we will have in this call
+            var typeArguments; // Type arguments (undefined if none)
+            var callIsIncomplete = false; // In incomplete call we want to be lenient when we have too few arguments
+            var spreadArgIndex = -1;
+            if (ts.isJsxOpeningLikeElement(node)) {
+                // The arity check will be done in "checkApplicableSignatureForJsxOpeningLikeElement".
+                return true;
+            }
+            if (node.kind === 189 /* TaggedTemplateExpression */) {
+                // Even if the call is incomplete, we'll have a missing expression as our last argument,
+                // so we can say the count is just the arg list length
+                argCount = args.length;
+                typeArguments = node.typeArguments;
+                if (node.template.kind === 202 /* TemplateExpression */) {
+                    // If a tagged template expression lacks a tail literal, the call is incomplete.
+                    // Specifically, a template only can end in a TemplateTail or a Missing literal.
+                    var lastSpan = ts.last(node.template.templateSpans); // we should always have at least one span.
+                    callIsIncomplete = ts.nodeIsMissing(lastSpan.literal) || !!lastSpan.literal.isUnterminated;
+                }
+                else {
+                    // If the template didn't end in a backtick, or its beginning occurred right prior to EOF,
+                    // then this might actually turn out to be a TemplateHead in the future;
+                    // so we consider the call to be incomplete.
+                    var templateLiteral = node.template;
+                    ts.Debug.assert(templateLiteral.kind === 13 /* NoSubstitutionTemplateLiteral */);
+                    callIsIncomplete = !!templateLiteral.isUnterminated;
+                }
+            }
+            else if (node.kind === 150 /* Decorator */) {
+                typeArguments = undefined;
+                argCount = getEffectiveArgumentCount(node, /*args*/ undefined, signature);
+            }
+            else {
+                if (!node.arguments) {
+                    // This only happens when we have something of the form: 'new C'
+                    ts.Debug.assert(node.kind === 188 /* NewExpression */);
+                    return signature.minArgumentCount === 0;
+                }
+                argCount = signatureHelpTrailingComma ? args.length + 1 : args.length;
+                // If we are missing the close parenthesis, the call is incomplete.
+                callIsIncomplete = node.arguments.end === node.end;
+                typeArguments = node.typeArguments;
+                spreadArgIndex = getSpreadArgumentIndex(args);
+            }
+            if (!hasCorrectTypeArgumentArity(signature, typeArguments)) {
+                return false;
+            }
+            // If a spread argument is present, check that it corresponds to a rest parameter or at least that it's in the valid range.
+            if (spreadArgIndex >= 0) {
+                return isRestParameterIndex(signature, spreadArgIndex) ||
+                    signature.minArgumentCount <= spreadArgIndex && spreadArgIndex < signature.parameters.length;
+            }
+            // Too many arguments implies incorrect arity.
+            if (!signature.hasRestParameter && argCount > signature.parameters.length) {
+                return false;
+            }
+            // If the call is incomplete, we should skip the lower bound check.
+            var hasEnoughArguments = argCount >= signature.minArgumentCount;
+            return callIsIncomplete || hasEnoughArguments;
+        }
+        function hasCorrectTypeArgumentArity(signature, typeArguments) {
+            // If the user supplied type arguments, but the number of type arguments does not match
+            // the declared number of type parameters, the call has an incorrect arity.
+            var numTypeParameters = ts.length(signature.typeParameters);
+            var minTypeArgumentCount = getMinTypeArgumentCount(signature.typeParameters);
+            return !typeArguments ||
+                (typeArguments.length >= minTypeArgumentCount && typeArguments.length <= numTypeParameters);
+        }
+        // If type has a single call signature and no other members, return that signature. Otherwise, return undefined.
+        function getSingleCallSignature(type) {
+            if (type.flags & 131072 /* Object */) {
+                var resolved = resolveStructuredTypeMembers(type);
+                if (resolved.callSignatures.length === 1 && resolved.constructSignatures.length === 0 &&
+                    resolved.properties.length === 0 && !resolved.stringIndexInfo && !resolved.numberIndexInfo) {
+                    return resolved.callSignatures[0];
+                }
+            }
+            return undefined;
+        }
+        // Instantiate a generic signature in the context of a non-generic signature (section 3.8.5 in TypeScript spec)
+        function instantiateSignatureInContextOf(signature, contextualSignature, contextualMapper, compareTypes) {
+            var context = createInferenceContext(signature.typeParameters, signature, 1 /* InferUnionTypes */, compareTypes);
+            forEachMatchingParameterType(contextualSignature, signature, function (source, target) {
+                // Type parameters from outer context referenced by source type are fixed by instantiation of the source type
+                inferTypes(context.inferences, instantiateType(source, contextualMapper || identityMapper), target);
+            });
+            if (!contextualMapper) {
+                inferTypes(context.inferences, getReturnTypeOfSignature(contextualSignature), getReturnTypeOfSignature(signature), 8 /* ReturnType */);
+            }
+            return getSignatureInstantiation(signature, getInferredTypes(context), ts.isInJavaScriptFile(contextualSignature.declaration));
+        }
+        function inferJsxTypeArguments(signature, node, context) {
+            // Skip context sensitive pass
+            var skipContextParamType = getTypeAtPosition(signature, 0);
+            var checkAttrTypeSkipContextSensitive = checkExpressionWithContextualType(node.attributes, skipContextParamType, identityMapper);
+            inferTypes(context.inferences, checkAttrTypeSkipContextSensitive, skipContextParamType);
+            // Standard pass
+            var paramType = getTypeAtPosition(signature, 0);
+            var checkAttrType = checkExpressionWithContextualType(node.attributes, paramType, context);
+            inferTypes(context.inferences, checkAttrType, paramType);
+            return getInferredTypes(context);
+        }
+        function inferTypeArguments(node, signature, args, excludeArgument, context) {
+            // Clear out all the inference results from the last time inferTypeArguments was called on this context
+            for (var _i = 0, _a = context.inferences; _i < _a.length; _i++) {
+                var inference = _a[_i];
+                // As an optimization, we don't have to clear (and later recompute) inferred types
+                // for type parameters that have already been fixed on the previous call to inferTypeArguments.
+                // It would be just as correct to reset all of them. But then we'd be repeating the same work
+                // for the type parameters that were fixed, namely the work done by getInferredType.
+                if (!inference.isFixed) {
+                    inference.inferredType = undefined;
+                }
+            }
+            // If a contextual type is available, infer from that type to the return type of the call expression. For
+            // example, given a 'function wrap<T, U>(cb: (x: T) => U): (x: T) => U' and a call expression
+            // 'let f: (x: string) => number = wrap(s => s.length)', we infer from the declared type of 'f' to the
+            // return type of 'wrap'.
+            if (node.kind !== 150 /* Decorator */) {
+                var contextualType = getContextualType(node);
+                if (contextualType) {
+                    // We clone the contextual mapper to avoid disturbing a resolution in progress for an
+                    // outer call expression. Effectively we just want a snapshot of whatever has been
+                    // inferred for any outer call expression so far.
+                    var instantiatedType = instantiateType(contextualType, cloneTypeMapper(getContextualMapper(node)));
+                    // If the contextual type is a generic function type with a single call signature, we
+                    // instantiate the type with its own type parameters and type arguments. This ensures that
+                    // the type parameters are not erased to type any during type inference such that they can
+                    // be inferred as actual types from the contextual type. For example:
+                    //   declare function arrayMap<T, U>(f: (x: T) => U): (a: T[]) => U[];
+                    //   const boxElements: <A>(a: A[]) => { value: A }[] = arrayMap(value => ({ value }));
+                    // Above, the type of the 'value' parameter is inferred to be 'A'.
+                    var contextualSignature = getSingleCallSignature(instantiatedType);
+                    var inferenceSourceType = contextualSignature && contextualSignature.typeParameters ?
+                        getOrCreateTypeFromSignature(getSignatureInstantiation(contextualSignature, contextualSignature.typeParameters, ts.isInJavaScriptFile(node))) :
+                        instantiatedType;
+                    var inferenceTargetType = getReturnTypeOfSignature(signature);
+                    // Inferences made from return types have lower priority than all other inferences.
+                    inferTypes(context.inferences, inferenceSourceType, inferenceTargetType, 8 /* ReturnType */);
+                }
+            }
+            var thisType = getThisTypeOfSignature(signature);
+            if (thisType) {
+                var thisArgumentNode = getThisArgumentOfCall(node);
+                var thisArgumentType = thisArgumentNode ? checkExpression(thisArgumentNode) : voidType;
+                inferTypes(context.inferences, thisArgumentType, thisType);
+            }
+            // We perform two passes over the arguments. In the first pass we infer from all arguments, but use
+            // wildcards for all context sensitive function expressions.
+            var argCount = getEffectiveArgumentCount(node, args, signature);
+            for (var i = 0; i < argCount; i++) {
+                var arg = getEffectiveArgument(node, args, i);
+                // If the effective argument is 'undefined', then it is an argument that is present but is synthetic.
+                if (arg === undefined || arg.kind !== 206 /* OmittedExpression */) {
+                    var paramType = getTypeAtPosition(signature, i);
+                    var argType = getEffectiveArgumentType(node, i);
+                    // If the effective argument type is 'undefined', there is no synthetic type
+                    // for the argument. In that case, we should check the argument.
+                    if (argType === undefined) {
+                        // For context sensitive arguments we pass the identityMapper, which is a signal to treat all
+                        // context sensitive function expressions as wildcards
+                        var mapper = excludeArgument && excludeArgument[i] !== undefined ? identityMapper : context;
+                        argType = checkExpressionWithContextualType(arg, paramType, mapper);
+                    }
+                    inferTypes(context.inferences, argType, paramType);
+                }
+            }
+            // In the second pass we visit only context sensitive arguments, and only those that aren't excluded, this
+            // time treating function expressions normally (which may cause previously inferred type arguments to be fixed
+            // as we construct types for contextually typed parameters)
+            // Decorators will not have `excludeArgument`, as their arguments cannot be contextually typed.
+            // Tagged template expressions will always have `undefined` for `excludeArgument[0]`.
+            if (excludeArgument) {
+                for (var i = 0; i < argCount; i++) {
+                    // No need to check for omitted args and template expressions, their exclusion value is always undefined
+                    if (excludeArgument[i] === false) {
+                        var arg = args[i];
+                        var paramType = getTypeAtPosition(signature, i);
+                        inferTypes(context.inferences, checkExpressionWithContextualType(arg, paramType, context), paramType);
+                    }
+                }
+            }
+            return getInferredTypes(context);
+        }
+        function checkTypeArguments(signature, typeArgumentNodes, reportErrors, headMessage) {
+            var isJavascript = ts.isInJavaScriptFile(signature.declaration);
+            var typeParameters = signature.typeParameters;
+            var typeArgumentTypes = fillMissingTypeArguments(ts.map(typeArgumentNodes, getTypeFromTypeNode), typeParameters, getMinTypeArgumentCount(typeParameters), isJavascript);
+            var mapper;
+            for (var i = 0; i < typeArgumentNodes.length; i++) {
+                ts.Debug.assert(typeParameters[i] !== undefined, "Should not call checkTypeArguments with too many type arguments");
+                var constraint = getConstraintOfTypeParameter(typeParameters[i]);
+                if (!constraint)
+                    continue;
+                var errorInfo = reportErrors && headMessage ? (function () { return ts.chainDiagnosticMessages(/*details*/ undefined, ts.Diagnostics.Type_0_does_not_satisfy_the_constraint_1); }) : undefined;
+                var typeArgumentHeadMessage = headMessage || ts.Diagnostics.Type_0_does_not_satisfy_the_constraint_1;
+                if (!mapper) {
+                    mapper = createTypeMapper(typeParameters, typeArgumentTypes);
+                }
+                var typeArgument = typeArgumentTypes[i];
+                if (!checkTypeAssignableTo(typeArgument, getTypeWithThisArgument(instantiateType(constraint, mapper), typeArgument), reportErrors ? typeArgumentNodes[i] : undefined, typeArgumentHeadMessage, errorInfo)) {
+                    return false;
+                }
+            }
+            return typeArgumentTypes;
+        }
+        /**
+         * Check if the given signature can possibly be a signature called by the JSX opening-like element.
+         * @param node a JSX opening-like element we are trying to figure its call signature
+         * @param signature a candidate signature we are trying whether it is a call signature
+         * @param relation a relationship to check parameter and argument type
+         * @param excludeArgument
+         */
+        function checkApplicableSignatureForJsxOpeningLikeElement(node, signature, relation) {
+            // JSX opening-like element has correct arity for stateless-function component if the one of the following condition is true:
+            //      1. callIsIncomplete
+            //      2. attributes property has same number of properties as the parameter object type.
+            //         We can figure that out by resolving attributes property and check number of properties in the resolved type
+            // If the call has correct arity, we will then check if the argument type and parameter type is assignable
+            var callIsIncomplete = node.attributes.end === node.end; // If we are missing the close "/>", the call is incomplete
+            if (callIsIncomplete) {
+                return true;
+            }
+            var headMessage = ts.Diagnostics.Argument_of_type_0_is_not_assignable_to_parameter_of_type_1;
+            // Stateless function components can have maximum of three arguments: "props", "context", and "updater".
+            // However "context" and "updater" are implicit and can't be specify by users. Only the first parameter, props,
+            // can be specified by users through attributes property.
+            var paramType = getTypeAtPosition(signature, 0);
+            var attributesType = checkExpressionWithContextualType(node.attributes, paramType, /*contextualMapper*/ undefined);
+            var argProperties = getPropertiesOfType(attributesType);
+            for (var _i = 0, argProperties_1 = argProperties; _i < argProperties_1.length; _i++) {
+                var arg = argProperties_1[_i];
+                if (!getPropertyOfType(paramType, arg.escapedName) && isUnhyphenatedJsxName(arg.escapedName)) {
+                    return false;
+                }
+            }
+            return checkTypeRelatedTo(attributesType, paramType, relation, /*errorNode*/ undefined, headMessage);
+        }
+        function checkApplicableSignature(node, args, signature, relation, excludeArgument, reportErrors) {
+            if (ts.isJsxOpeningLikeElement(node)) {
+                return checkApplicableSignatureForJsxOpeningLikeElement(node, signature, relation);
+            }
+            var thisType = getThisTypeOfSignature(signature);
+            if (thisType && thisType !== voidType && node.kind !== 188 /* NewExpression */) {
+                // If the called expression is not of the form `x.f` or `x["f"]`, then sourceType = voidType
+                // If the signature's 'this' type is voidType, then the check is skipped -- anything is compatible.
+                // If the expression is a new expression, then the check is skipped.
+                var thisArgumentNode = getThisArgumentOfCall(node);
+                var thisArgumentType = thisArgumentNode ? checkExpression(thisArgumentNode) : voidType;
+                var errorNode = reportErrors ? (thisArgumentNode || node) : undefined;
+                var headMessage_1 = ts.Diagnostics.The_this_context_of_type_0_is_not_assignable_to_method_s_this_of_type_1;
+                if (!checkTypeRelatedTo(thisArgumentType, thisType, relation, errorNode, headMessage_1)) {
+                    return false;
+                }
+            }
+            var headMessage = ts.Diagnostics.Argument_of_type_0_is_not_assignable_to_parameter_of_type_1;
+            var argCount = getEffectiveArgumentCount(node, args, signature);
+            for (var i = 0; i < argCount; i++) {
+                var arg = getEffectiveArgument(node, args, i);
+                // If the effective argument is 'undefined', then it is an argument that is present but is synthetic.
+                if (arg === undefined || arg.kind !== 206 /* OmittedExpression */) {
+                    // Check spread elements against rest type (from arity check we know spread argument corresponds to a rest parameter)
+                    var paramType = getTypeAtPosition(signature, i);
+                    // If the effective argument type is undefined, there is no synthetic type for the argument.
+                    // In that case, we should check the argument.
+                    var argType = getEffectiveArgumentType(node, i) ||
+                        checkExpressionWithContextualType(arg, paramType, excludeArgument && excludeArgument[i] ? identityMapper : undefined);
+                    // If one or more arguments are still excluded (as indicated by a non-null excludeArgument parameter),
+                    // we obtain the regular type of any object literal arguments because we may not have inferred complete
+                    // parameter types yet and therefore excess property checks may yield false positives (see #17041).
+                    var checkArgType = excludeArgument ? getRegularTypeOfObjectLiteral(argType) : argType;
+                    // Use argument expression as error location when reporting errors
+                    var errorNode = reportErrors ? getEffectiveArgumentErrorNode(node, i, arg) : undefined;
+                    if (!checkTypeRelatedTo(checkArgType, paramType, relation, errorNode, headMessage)) {
+                        return false;
+                    }
+                }
+            }
+            return true;
+        }
+        /**
+         * Returns the this argument in calls like x.f(...) and x[f](...). Undefined otherwise.
+         */
+        function getThisArgumentOfCall(node) {
+            if (node.kind === 187 /* CallExpression */) {
+                var callee = ts.skipOuterExpressions(node.expression);
+                if (callee.kind === 185 /* PropertyAccessExpression */ || callee.kind === 186 /* ElementAccessExpression */) {
+                    return callee.expression;
+                }
+            }
+        }
+        /**
+         * Returns the effective arguments for an expression that works like a function invocation.
+         *
+         * If 'node' is a CallExpression or a NewExpression, then its argument list is returned.
+         * If 'node' is a TaggedTemplateExpression, a new argument list is constructed from the substitution
+         *    expressions, where the first element of the list is `undefined`.
+         * If 'node' is a Decorator, the argument list will be `undefined`, and its arguments and types
+         *    will be supplied from calls to `getEffectiveArgumentCount` and `getEffectiveArgumentType`.
+         */
+        function getEffectiveCallArguments(node) {
+            if (node.kind === 189 /* TaggedTemplateExpression */) {
+                var template = node.template;
+                var args_4 = [undefined]; // TODO: GH#18217
+                if (template.kind === 202 /* TemplateExpression */) {
+                    ts.forEach(template.templateSpans, function (span) {
+                        args_4.push(span.expression);
+                    });
+                }
+                return args_4;
+            }
+            else if (node.kind === 150 /* Decorator */) {
+                // For a decorator, we return undefined as we will determine
+                // the number and types of arguments for a decorator using
+                // `getEffectiveArgumentCount` and `getEffectiveArgumentType` below.
+                return undefined;
+            }
+            else if (ts.isJsxOpeningLikeElement(node)) {
+                return node.attributes.properties.length > 0 ? [node.attributes] : ts.emptyArray;
+            }
+            else {
+                return node.arguments || ts.emptyArray;
+            }
+        }
+        /**
+         * Returns the effective argument count for a node that works like a function invocation.
+         * If 'node' is a Decorator, the number of arguments is derived from the decoration
+         *    target and the signature:
+         *    If 'node.target' is a class declaration or class expression, the effective argument
+         *       count is 1.
+         *    If 'node.target' is a parameter declaration, the effective argument count is 3.
+         *    If 'node.target' is a property declaration, the effective argument count is 2.
+         *    If 'node.target' is a method or accessor declaration, the effective argument count
+         *       is 3, although it can be 2 if the signature only accepts two arguments, allowing
+         *       us to match a property decorator.
+         * Otherwise, the argument count is the length of the 'args' array.
+         */
+        function getEffectiveArgumentCount(node, args, signature) {
+            if (node.kind === 150 /* Decorator */) {
+                switch (node.parent.kind) {
+                    case 235 /* ClassDeclaration */:
+                    case 205 /* ClassExpression */:
+                        // A class decorator will have one argument (see `ClassDecorator` in core.d.ts)
+                        return 1;
+                    case 152 /* PropertyDeclaration */:
+                        // A property declaration decorator will have two arguments (see
+                        // `PropertyDecorator` in core.d.ts)
+                        return 2;
+                    case 154 /* MethodDeclaration */:
+                    case 156 /* GetAccessor */:
+                    case 157 /* SetAccessor */:
+                        // A method or accessor declaration decorator will have two or three arguments (see
+                        // `PropertyDecorator` and `MethodDecorator` in core.d.ts)
+                        // If we are emitting decorators for ES3, we will only pass two arguments.
+                        if (languageVersion === 0 /* ES3 */) {
+                            return 2;
+                        }
+                        // If the method decorator signature only accepts a target and a key, we will only
+                        // type check those arguments.
+                        return signature.parameters.length >= 3 ? 3 : 2;
+                    case 149 /* Parameter */:
+                        // A parameter declaration decorator will have three arguments (see
+                        // `ParameterDecorator` in core.d.ts)
+                        return 3;
+                    default:
+                        return ts.Debug.fail();
+                }
+            }
+            else {
+                return args.length;
+            }
+        }
+        /**
+         * Returns the effective type of the first argument to a decorator.
+         * If 'node' is a class declaration or class expression, the effective argument type
+         *    is the type of the static side of the class.
+         * If 'node' is a parameter declaration, the effective argument type is either the type
+         *    of the static or instance side of the class for the parameter's parent method,
+         *    depending on whether the method is declared static.
+         *    For a constructor, the type is always the type of the static side of the class.
+         * If 'node' is a property, method, or accessor declaration, the effective argument
+         *    type is the type of the static or instance side of the parent class for class
+         *    element, depending on whether the element is declared static.
+         */
+        function getEffectiveDecoratorFirstArgumentType(node) {
+            // The first argument to a decorator is its `target`.
+            if (node.kind === 235 /* ClassDeclaration */) {
+                // For a class decorator, the `target` is the type of the class (e.g. the
+                // "static" or "constructor" side of the class)
+                var classSymbol = getSymbolOfNode(node);
+                return getTypeOfSymbol(classSymbol);
+            }
+            if (node.kind === 149 /* Parameter */) {
+                // For a parameter decorator, the `target` is the parent type of the
+                // parameter's containing method.
+                node = node.parent;
+                if (node.kind === 155 /* Constructor */) {
+                    var classSymbol = getSymbolOfNode(node);
+                    return getTypeOfSymbol(classSymbol);
+                }
+            }
+            if (node.kind === 152 /* PropertyDeclaration */ ||
+                node.kind === 154 /* MethodDeclaration */ ||
+                node.kind === 156 /* GetAccessor */ ||
+                node.kind === 157 /* SetAccessor */) {
+                // For a property or method decorator, the `target` is the
+                // "static"-side type of the parent of the member if the member is
+                // declared "static"; otherwise, it is the "instance"-side type of the
+                // parent of the member.
+                return getParentTypeOfClassElement(node);
+            }
+            ts.Debug.fail("Unsupported decorator target.");
+            return errorType;
+        }
+        /**
+         * Returns the effective type for the second argument to a decorator.
+         * If 'node' is a parameter, its effective argument type is one of the following:
+         *    If 'node.parent' is a constructor, the effective argument type is 'any', as we
+         *       will emit `undefined`.
+         *    If 'node.parent' is a member with an identifier, numeric, or string literal name,
+         *       the effective argument type will be a string literal type for the member name.
+         *    If 'node.parent' is a computed property name, the effective argument type will
+         *       either be a symbol type or the string type.
+         * If 'node' is a member with an identifier, numeric, or string literal name, the
+         *    effective argument type will be a string literal type for the member name.
+         * If 'node' is a computed property name, the effective argument type will either
+         *    be a symbol type or the string type.
+         * A class decorator does not have a second argument type.
+         */
+        function getEffectiveDecoratorSecondArgumentType(node) {
+            // The second argument to a decorator is its `propertyKey`
+            if (node.kind === 235 /* ClassDeclaration */) {
+                ts.Debug.fail("Class decorators should not have a second synthetic argument.");
+                return errorType;
+            }
+            if (node.kind === 149 /* Parameter */) {
+                node = node.parent;
+                if (node.kind === 155 /* Constructor */) {
+                    // For a constructor parameter decorator, the `propertyKey` will be `undefined`.
+                    return anyType;
+                }
+                // For a non-constructor parameter decorator, the `propertyKey` will be either
+                // a string or a symbol, based on the name of the parameter's containing method.
+            }
+            if (node.kind === 152 /* PropertyDeclaration */ ||
+                node.kind === 154 /* MethodDeclaration */ ||
+                node.kind === 156 /* GetAccessor */ ||
+                node.kind === 157 /* SetAccessor */) {
+                // The `propertyKey` for a property or method decorator will be a
+                // string literal type if the member name is an identifier, number, or string;
+                // otherwise, if the member name is a computed property name it will
+                // be either string or symbol.
+                var element = node;
+                var name = element.name;
+                switch (name.kind) {
+                    case 71 /* Identifier */:
+                        return getLiteralType(ts.idText(name));
+                    case 8 /* NumericLiteral */:
+                    case 9 /* StringLiteral */:
+                        return getLiteralType(name.text);
+                    case 147 /* ComputedPropertyName */:
+                        var nameType = checkComputedPropertyName(name);
+                        if (isTypeAssignableToKind(nameType, 3072 /* ESSymbolLike */)) {
+                            return nameType;
+                        }
+                        else {
+                            return stringType;
+                        }
+                    default:
+                        ts.Debug.fail("Unsupported property name.");
+                        return errorType;
+                }
+            }
+            ts.Debug.fail("Unsupported decorator target.");
+            return errorType;
+        }
+        /**
+         * Returns the effective argument type for the third argument to a decorator.
+         * If 'node' is a parameter, the effective argument type is the number type.
+         * If 'node' is a method or accessor, the effective argument type is a
+         *    `TypedPropertyDescriptor<T>` instantiated with the type of the member.
+         * Class and property decorators do not have a third effective argument.
+         */
+        function getEffectiveDecoratorThirdArgumentType(node) {
+            // The third argument to a decorator is either its `descriptor` for a method decorator
+            // or its `parameterIndex` for a parameter decorator
+            if (node.kind === 235 /* ClassDeclaration */) {
+                ts.Debug.fail("Class decorators should not have a third synthetic argument.");
+                return errorType;
+            }
+            if (node.kind === 149 /* Parameter */) {
+                // The `parameterIndex` for a parameter decorator is always a number
+                return numberType;
+            }
+            if (node.kind === 152 /* PropertyDeclaration */) {
+                ts.Debug.fail("Property decorators should not have a third synthetic argument.");
+                return errorType;
+            }
+            if (node.kind === 154 /* MethodDeclaration */ ||
+                node.kind === 156 /* GetAccessor */ ||
+                node.kind === 157 /* SetAccessor */) {
+                // The `descriptor` for a method decorator will be a `TypedPropertyDescriptor<T>`
+                // for the type of the member.
+                var propertyType = getTypeOfNode(node); // TODO: GH#18217
+                return createTypedPropertyDescriptorType(propertyType);
+            }
+            ts.Debug.fail("Unsupported decorator target.");
+            return errorType;
+        }
+        /**
+         * Returns the effective argument type for the provided argument to a decorator.
+         */
+        function getEffectiveDecoratorArgumentType(node, argIndex) {
+            if (argIndex === 0) {
+                return getEffectiveDecoratorFirstArgumentType(node.parent);
+            }
+            else if (argIndex === 1) {
+                return getEffectiveDecoratorSecondArgumentType(node.parent);
+            }
+            else if (argIndex === 2) {
+                return getEffectiveDecoratorThirdArgumentType(node.parent);
+            }
+            ts.Debug.fail("Decorators should not have a fourth synthetic argument.");
+            return errorType;
+        }
+        /**
+         * Gets the effective argument type for an argument in a call expression.
+         */
+        function getEffectiveArgumentType(node, argIndex) {
+            // Decorators provide special arguments, a tagged template expression provides
+            // a special first argument, and string literals get string literal types
+            // unless we're reporting errors
+            if (node.kind === 150 /* Decorator */) {
+                return getEffectiveDecoratorArgumentType(node, argIndex);
+            }
+            else if (argIndex === 0 && node.kind === 189 /* TaggedTemplateExpression */) {
+                return getGlobalTemplateStringsArrayType();
+            }
+            // This is not a synthetic argument, so we return 'undefined'
+            // to signal that the caller needs to check the argument.
+            return undefined;
+        }
+        /**
+         * Gets the effective argument expression for an argument in a call expression.
+         */
+        function getEffectiveArgument(node, args, argIndex) {
+            // For a decorator or the first argument of a tagged template expression we return undefined.
+            if (node.kind === 150 /* Decorator */ ||
+                (argIndex === 0 && node.kind === 189 /* TaggedTemplateExpression */)) {
+                return undefined;
+            }
+            return args[argIndex];
+        }
+        /**
+         * Gets the error node to use when reporting errors for an effective argument.
+         */
+        function getEffectiveArgumentErrorNode(node, argIndex, arg) {
+            if (node.kind === 150 /* Decorator */) {
+                // For a decorator, we use the expression of the decorator for error reporting.
+                return node.expression;
+            }
+            else if (argIndex === 0 && node.kind === 189 /* TaggedTemplateExpression */) {
+                // For a the first argument of a tagged template expression, we use the template of the tag for error reporting.
+                return node.template;
+            }
+            else {
+                return arg;
+            }
+        }
+        function getTypeArgumentArityError(node, signatures, typeArguments) {
+            var min = Infinity;
+            var max = -Infinity;
+            for (var _i = 0, signatures_5 = signatures; _i < signatures_5.length; _i++) {
+                var sig = signatures_5[_i];
+                min = Math.min(min, getMinTypeArgumentCount(sig.typeParameters));
+                max = Math.max(max, ts.length(sig.typeParameters));
+            }
+            var paramCount = min === max ? min : min + "-" + max;
+            return ts.createDiagnosticForNodeArray(ts.getSourceFileOfNode(node), typeArguments, ts.Diagnostics.Expected_0_type_arguments_but_got_1, paramCount, typeArguments.length);
+        }
+        function resolveCall(node, signatures, candidatesOutArray, fallbackError) {
+            var isTaggedTemplate = node.kind === 189 /* TaggedTemplateExpression */;
+            var isDecorator = node.kind === 150 /* Decorator */;
+            var isJsxOpeningOrSelfClosingElement = ts.isJsxOpeningLikeElement(node);
+            var typeArguments;
+            if (!isDecorator) {
+                typeArguments = node.typeArguments;
+                // We already perform checking on the type arguments on the class declaration itself.
+                if (isTaggedTemplate || isJsxOpeningOrSelfClosingElement || node.expression.kind !== 97 /* SuperKeyword */) {
+                    ts.forEach(typeArguments, checkSourceElement);
+                }
+            }
+            var candidates = candidatesOutArray || [];
+            // reorderCandidates fills up the candidates array directly
+            reorderCandidates(signatures, candidates);
+            if (!candidates.length) {
+                diagnostics.add(ts.createDiagnosticForNode(node, ts.Diagnostics.Call_target_does_not_contain_any_signatures));
+                return resolveErrorCall(node);
+            }
+            var args = getEffectiveCallArguments(node);
+            // The following applies to any value of 'excludeArgument[i]':
+            //    - true:      the argument at 'i' is susceptible to a one-time permanent contextual typing.
+            //    - undefined: the argument at 'i' is *not* susceptible to permanent contextual typing.
+            //    - false:     the argument at 'i' *was* and *has been* permanently contextually typed.
+            //
+            // The idea is that we will perform type argument inference & assignability checking once
+            // without using the susceptible parameters that are functions, and once more for each of those
+            // parameters, contextually typing each as we go along.
+            //
+            // For a tagged template, then the first argument be 'undefined' if necessary
+            // because it represents a TemplateStringsArray.
+            //
+            // For a decorator, no arguments are susceptible to contextual typing due to the fact
+            // decorators are applied to a declaration by the emitter, and not to an expression.
+            var isSingleNonGenericCandidate = candidates.length === 1 && !candidates[0].typeParameters;
+            var excludeArgument;
+            var excludeCount = 0;
+            if (!isDecorator && !isSingleNonGenericCandidate) {
+                // We do not need to call `getEffectiveArgumentCount` here as it only
+                // applies when calculating the number of arguments for a decorator.
+                for (var i = isTaggedTemplate ? 1 : 0; i < args.length; i++) {
+                    if (isContextSensitive(args[i])) {
+                        if (!excludeArgument) {
+                            excludeArgument = new Array(args.length);
+                        }
+                        excludeArgument[i] = true;
+                        excludeCount++;
+                    }
+                }
+            }
+            // The following variables are captured and modified by calls to chooseOverload.
+            // If overload resolution or type argument inference fails, we want to report the
+            // best error possible. The best error is one which says that an argument was not
+            // assignable to a parameter. This implies that everything else about the overload
+            // was fine. So if there is any overload that is only incorrect because of an
+            // argument, we will report an error on that one.
+            //
+            //     function foo(s: string): void;
+            //     function foo(n: number): void; // Report argument error on this overload
+            //     function foo(): void;
+            //     foo(true);
+            //
+            // If none of the overloads even made it that far, there are two possibilities.
+            // There was a problem with type arguments for some overload, in which case
+            // report an error on that. Or none of the overloads even had correct arity,
+            // in which case give an arity error.
+            //
+            //     function foo<T extends string>(x: T): void; // Report type argument error
+            //     function foo(): void;
+            //     foo<number>(0);
+            //
+            var candidateForArgumentError;
+            var candidateForTypeArgumentError;
+            var result;
+            // If we are in signature help, a trailing comma indicates that we intend to provide another argument,
+            // so we will only accept overloads with arity at least 1 higher than the current number of provided arguments.
+            var signatureHelpTrailingComma = candidatesOutArray && node.kind === 187 /* CallExpression */ && node.arguments.hasTrailingComma;
+            // Section 4.12.1:
+            // if the candidate list contains one or more signatures for which the type of each argument
+            // expression is a subtype of each corresponding parameter type, the return type of the first
+            // of those signatures becomes the return type of the function call.
+            // Otherwise, the return type of the first signature in the candidate list becomes the return
+            // type of the function call.
+            //
+            // Whether the call is an error is determined by assignability of the arguments. The subtype pass
+            // is just important for choosing the best signature. So in the case where there is only one
+            // signature, the subtype pass is useless. So skipping it is an optimization.
+            if (candidates.length > 1) {
+                result = chooseOverload(candidates, subtypeRelation, signatureHelpTrailingComma);
+            }
+            if (!result) {
+                result = chooseOverload(candidates, assignableRelation, signatureHelpTrailingComma);
+            }
+            if (result) {
+                return result;
+            }
+            // No signatures were applicable. Now report errors based on the last applicable signature with
+            // no arguments excluded from assignability checks.
+            // If candidate is undefined, it means that no candidates had a suitable arity. In that case,
+            // skip the checkApplicableSignature check.
+            if (candidateForArgumentError) {
+                if (isJsxOpeningOrSelfClosingElement) {
+                    // We do not report any error here because any error will be handled in "resolveCustomJsxElementAttributesType".
+                    return candidateForArgumentError;
+                }
+                // excludeArgument is undefined, in this case also equivalent to [undefined, undefined, ...]
+                // The importance of excludeArgument is to prevent us from typing function expression parameters
+                // in arguments too early. If possible, we'd like to only type them once we know the correct
+                // overload. However, this matters for the case where the call is correct. When the call is
+                // an error, we don't need to exclude any arguments, although it would cause no harm to do so.
+                checkApplicableSignature(node, args, candidateForArgumentError, assignableRelation, /*excludeArgument*/ undefined, /*reportErrors*/ true);
+            }
+            else if (candidateForTypeArgumentError) {
+                checkTypeArguments(candidateForTypeArgumentError, node.typeArguments, /*reportErrors*/ true, fallbackError);
+            }
+            else if (typeArguments && ts.every(signatures, function (sig) { return ts.length(sig.typeParameters) !== typeArguments.length; })) {
+                diagnostics.add(getTypeArgumentArityError(node, signatures, typeArguments));
+            }
+            else if (args) {
+                var min_1 = Number.POSITIVE_INFINITY;
+                var max = Number.NEGATIVE_INFINITY;
+                for (var _i = 0, signatures_6 = signatures; _i < signatures_6.length; _i++) {
+                    var sig = signatures_6[_i];
+                    min_1 = Math.min(min_1, sig.minArgumentCount);
+                    max = Math.max(max, sig.parameters.length);
+                }
+                var hasRestParameter_1 = ts.some(signatures, function (sig) { return sig.hasRestParameter; });
+                var hasSpreadArgument = getSpreadArgumentIndex(args) > -1;
+                var paramCount = hasRestParameter_1 ? min_1 :
+                    min_1 < max ? min_1 + "-" + max :
+                        min_1;
+                var argCount = args.length;
+                if (argCount <= max && hasSpreadArgument) {
+                    argCount--;
+                }
+                var error_1 = hasRestParameter_1 && hasSpreadArgument ? ts.Diagnostics.Expected_at_least_0_arguments_but_got_1_or_more :
+                    hasRestParameter_1 ? ts.Diagnostics.Expected_at_least_0_arguments_but_got_1 :
+                        hasSpreadArgument ? ts.Diagnostics.Expected_0_arguments_but_got_1_or_more :
+                            ts.Diagnostics.Expected_0_arguments_but_got_1;
+                diagnostics.add(ts.createDiagnosticForNode(node, error_1, paramCount, argCount));
+            }
+            else if (fallbackError) {
+                diagnostics.add(ts.createDiagnosticForNode(node, fallbackError));
+            }
+            // No signature was applicable. We have already reported the errors for the invalid signature.
+            // If this is a type resolution session, e.g. Language Service, try to get better information than anySignature.
+            // Pick the longest signature. This way we can get a contextual type for cases like:
+            //     declare function f(a: { xa: number; xb: number; }, b: number);
+            //     f({ |
+            // Also, use explicitly-supplied type arguments if they are provided, so we can get a contextual signature in cases like:
+            //     declare function f<T>(k: keyof T);
+            //     f<Foo>("
+            if (!produceDiagnostics) {
+                ts.Debug.assert(candidates.length > 0); // Else would have exited above.
+                var bestIndex = getLongestCandidateIndex(candidates, apparentArgumentCount === undefined ? args.length : apparentArgumentCount);
+                var candidate = candidates[bestIndex];
+                var typeParameters = candidate.typeParameters;
+                if (typeParameters && callLikeExpressionMayHaveTypeArguments(node) && node.typeArguments) {
+                    var typeArguments_1 = node.typeArguments.map(getTypeOfNode); // TODO: GH#18217
+                    while (typeArguments_1.length > typeParameters.length) {
+                        typeArguments_1.pop();
+                    }
+                    while (typeArguments_1.length < typeParameters.length) {
+                        typeArguments_1.push(getDefaultTypeArgumentType(ts.isInJavaScriptFile(node)));
+                    }
+                    var instantiated = createSignatureInstantiation(candidate, typeArguments_1);
+                    candidates[bestIndex] = instantiated;
+                    return instantiated;
+                }
+                return candidate;
+            }
+            return resolveErrorCall(node);
+            function chooseOverload(candidates, relation, signatureHelpTrailingComma) {
+                if (signatureHelpTrailingComma === void 0) { signatureHelpTrailingComma = false; }
+                candidateForArgumentError = undefined;
+                candidateForTypeArgumentError = undefined;
+                if (isSingleNonGenericCandidate) {
+                    var candidate = candidates[0];
+                    if (!hasCorrectArity(node, args, candidate, signatureHelpTrailingComma)) {
+                        return undefined;
+                    }
+                    if (!checkApplicableSignature(node, args, candidate, relation, excludeArgument, /*reportErrors*/ false)) {
+                        candidateForArgumentError = candidate;
+                        return undefined;
+                    }
+                    return candidate;
+                }
+                for (var candidateIndex = 0; candidateIndex < candidates.length; candidateIndex++) {
+                    var originalCandidate = candidates[candidateIndex];
+                    if (!hasCorrectArity(node, args, originalCandidate, signatureHelpTrailingComma)) {
+                        continue;
+                    }
+                    var candidate = void 0;
+                    var inferenceContext = originalCandidate.typeParameters ?
+                        createInferenceContext(originalCandidate.typeParameters, originalCandidate, /*flags*/ ts.isInJavaScriptFile(node) ? 4 /* AnyDefault */ : 0 /* None */) :
+                        undefined;
+                    while (true) {
+                        candidate = originalCandidate;
+                        if (candidate.typeParameters) {
+                            var typeArgumentTypes = void 0;
+                            if (typeArguments) {
+                                var typeArgumentResult = checkTypeArguments(candidate, typeArguments, /*reportErrors*/ false);
+                                if (typeArgumentResult) {
+                                    typeArgumentTypes = typeArgumentResult;
+                                }
+                                else {
+                                    candidateForTypeArgumentError = originalCandidate;
+                                    break;
+                                }
+                            }
+                            else {
+                                typeArgumentTypes = inferTypeArguments(node, candidate, args, excludeArgument, inferenceContext);
+                            }
+                            var isJavascript = ts.isInJavaScriptFile(candidate.declaration);
+                            candidate = getSignatureInstantiation(candidate, typeArgumentTypes, isJavascript);
+                        }
+                        if (!checkApplicableSignature(node, args, candidate, relation, excludeArgument, /*reportErrors*/ false)) {
+                            candidateForArgumentError = candidate;
+                            break;
+                        }
+                        if (excludeCount === 0) {
+                            candidates[candidateIndex] = candidate;
+                            return candidate;
+                        }
+                        excludeCount--;
+                        if (excludeCount > 0) {
+                            excludeArgument[excludeArgument.indexOf(/*value*/ true)] = false;
+                        }
+                        else {
+                            excludeArgument = undefined;
+                        }
+                    }
+                }
+                return undefined;
+            }
+        }
+        function getLongestCandidateIndex(candidates, argsCount) {
+            var maxParamsIndex = -1;
+            var maxParams = -1;
+            for (var i = 0; i < candidates.length; i++) {
+                var candidate = candidates[i];
+                if (candidate.hasRestParameter || candidate.parameters.length >= argsCount) {
+                    return i;
+                }
+                if (candidate.parameters.length > maxParams) {
+                    maxParams = candidate.parameters.length;
+                    maxParamsIndex = i;
+                }
+            }
+            return maxParamsIndex;
+        }
+        function resolveCallExpression(node, candidatesOutArray) {
+            if (node.expression.kind === 97 /* SuperKeyword */) {
+                var superType = checkSuperExpression(node.expression);
+                if (isTypeAny(superType)) {
+                    ts.forEach(node.arguments, checkExpresionNoReturn); // Still visit arguments so they get marked for visibility, etc
+                    return anySignature;
+                }
+                if (superType !== errorType) {
+                    // In super call, the candidate signatures are the matching arity signatures of the base constructor function instantiated
+                    // with the type arguments specified in the extends clause.
+                    var baseTypeNode = ts.getClassExtendsHeritageClauseElement(ts.getContainingClass(node));
+                    if (baseTypeNode) {
+                        var baseConstructors = getInstantiatedConstructorsForTypeArguments(superType, baseTypeNode.typeArguments, baseTypeNode);
+                        return resolveCall(node, baseConstructors, candidatesOutArray);
+                    }
+                }
+                return resolveUntypedCall(node);
+            }
+            var funcType = checkNonNullExpression(node.expression, ts.Diagnostics.Cannot_invoke_an_object_which_is_possibly_null, ts.Diagnostics.Cannot_invoke_an_object_which_is_possibly_undefined, ts.Diagnostics.Cannot_invoke_an_object_which_is_possibly_null_or_undefined);
+            if (funcType === silentNeverType) {
+                return silentNeverSignature;
+            }
+            var apparentType = getApparentType(funcType);
+            if (apparentType === errorType) {
+                // Another error has already been reported
+                return resolveErrorCall(node);
+            }
+            // Technically, this signatures list may be incomplete. We are taking the apparent type,
+            // but we are not including call signatures that may have been added to the Object or
+            // Function interface, since they have none by default. This is a bit of a leap of faith
+            // that the user will not add any.
+            var callSignatures = getSignaturesOfType(apparentType, 0 /* Call */);
+            var constructSignatures = getSignaturesOfType(apparentType, 1 /* Construct */);
+            // TS 1.0 Spec: 4.12
+            // In an untyped function call no TypeArgs are permitted, Args can be any argument list, no contextual
+            // types are provided for the argument expressions, and the result is always of type Any.
+            if (isUntypedFunctionCall(funcType, apparentType, callSignatures.length, constructSignatures.length)) {
+                // The unknownType indicates that an error already occurred (and was reported).  No
+                // need to report another error in this case.
+                if (funcType !== errorType && node.typeArguments) {
+                    error(node, ts.Diagnostics.Untyped_function_calls_may_not_accept_type_arguments);
+                }
+                return resolveUntypedCall(node);
+            }
+            // If FuncExpr's apparent type(section 3.8.1) is a function type, the call is a typed function call.
+            // TypeScript employs overload resolution in typed function calls in order to support functions
+            // with multiple call signatures.
+            if (!callSignatures.length) {
+                if (constructSignatures.length) {
+                    error(node, ts.Diagnostics.Value_of_type_0_is_not_callable_Did_you_mean_to_include_new, typeToString(funcType));
+                }
+                else {
+                    invocationError(node, apparentType, 0 /* Call */);
+                }
+                return resolveErrorCall(node);
+            }
+            return resolveCall(node, callSignatures, candidatesOutArray);
+        }
+        /**
+         * TS 1.0 spec: 4.12
+         * If FuncExpr is of type Any, or of an object type that has no call or construct signatures
+         * but is a subtype of the Function interface, the call is an untyped function call.
+         */
+        function isUntypedFunctionCall(funcType, apparentFuncType, numCallSignatures, numConstructSignatures) {
+            // We exclude union types because we may have a union of function types that happen to have no common signatures.
+            return isTypeAny(funcType) || isTypeAny(apparentFuncType) && funcType.flags & 65536 /* TypeParameter */ ||
+                !numCallSignatures && !numConstructSignatures && !(apparentFuncType.flags & (262144 /* Union */ | 32768 /* Never */)) && isTypeAssignableTo(funcType, globalFunctionType);
+        }
+        function resolveNewExpression(node, candidatesOutArray) {
+            if (node.arguments && languageVersion < 1 /* ES5 */) {
+                var spreadIndex = getSpreadArgumentIndex(node.arguments);
+                if (spreadIndex >= 0) {
+                    error(node.arguments[spreadIndex], ts.Diagnostics.Spread_operator_in_new_expressions_is_only_available_when_targeting_ECMAScript_5_and_higher);
+                }
+            }
+            var expressionType = checkNonNullExpression(node.expression);
+            if (expressionType === silentNeverType) {
+                return silentNeverSignature;
+            }
+            // If expressionType's apparent type(section 3.8.1) is an object type with one or
+            // more construct signatures, the expression is processed in the same manner as a
+            // function call, but using the construct signatures as the initial set of candidate
+            // signatures for overload resolution. The result type of the function call becomes
+            // the result type of the operation.
+            expressionType = getApparentType(expressionType);
+            if (expressionType === errorType) {
+                // Another error has already been reported
+                return resolveErrorCall(node);
+            }
+            // TS 1.0 spec: 4.11
+            // If expressionType is of type Any, Args can be any argument
+            // list and the result of the operation is of type Any.
+            if (isTypeAny(expressionType)) {
+                if (node.typeArguments) {
+                    error(node, ts.Diagnostics.Untyped_function_calls_may_not_accept_type_arguments);
+                }
+                return resolveUntypedCall(node);
+            }
+            // Technically, this signatures list may be incomplete. We are taking the apparent type,
+            // but we are not including construct signatures that may have been added to the Object or
+            // Function interface, since they have none by default. This is a bit of a leap of faith
+            // that the user will not add any.
+            var constructSignatures = getSignaturesOfType(expressionType, 1 /* Construct */);
+            if (constructSignatures.length) {
+                if (!isConstructorAccessible(node, constructSignatures[0])) {
+                    return resolveErrorCall(node);
+                }
+                // If the expression is a class of abstract type, then it cannot be instantiated.
+                // Note, only class declarations can be declared abstract.
+                // In the case of a merged class-module or class-interface declaration,
+                // only the class declaration node will have the Abstract flag set.
+                var valueDecl = expressionType.symbol && ts.getClassLikeDeclarationOfSymbol(expressionType.symbol);
+                if (valueDecl && ts.hasModifier(valueDecl, 128 /* Abstract */)) {
+                    error(node, ts.Diagnostics.Cannot_create_an_instance_of_an_abstract_class);
+                    return resolveErrorCall(node);
+                }
+                return resolveCall(node, constructSignatures, candidatesOutArray);
+            }
+            // If expressionType's apparent type is an object type with no construct signatures but
+            // one or more call signatures, the expression is processed as a function call. A compile-time
+            // error occurs if the result of the function call is not Void. The type of the result of the
+            // operation is Any. It is an error to have a Void this type.
+            var callSignatures = getSignaturesOfType(expressionType, 0 /* Call */);
+            if (callSignatures.length) {
+                var signature = resolveCall(node, callSignatures, candidatesOutArray);
+                if (!isJavaScriptConstructor(signature.declaration) && getReturnTypeOfSignature(signature) !== voidType) {
+                    error(node, ts.Diagnostics.Only_a_void_function_can_be_called_with_the_new_keyword);
+                }
+                if (getThisTypeOfSignature(signature) === voidType) {
+                    error(node, ts.Diagnostics.A_function_that_is_called_with_the_new_keyword_cannot_have_a_this_type_that_is_void);
+                }
+                return signature;
+            }
+            invocationError(node, expressionType, 1 /* Construct */);
+            return resolveErrorCall(node);
+        }
+        function isConstructorAccessible(node, signature) {
+            if (!signature || !signature.declaration) {
+                return true;
+            }
+            var declaration = signature.declaration;
+            var modifiers = ts.getSelectedModifierFlags(declaration, 24 /* NonPublicAccessibilityModifier */);
+            // Public constructor is accessible.
+            if (!modifiers) {
+                return true;
+            }
+            var declaringClassDeclaration = ts.getClassLikeDeclarationOfSymbol(declaration.parent.symbol);
+            var declaringClass = getDeclaredTypeOfSymbol(declaration.parent.symbol);
+            // A private or protected constructor can only be instantiated within its own class (or a subclass, for protected)
+            if (!isNodeWithinClass(node, declaringClassDeclaration)) {
+                var containingClass = ts.getContainingClass(node);
+                if (containingClass) {
+                    var containingType = getTypeOfNode(containingClass);
+                    var baseTypes = getBaseTypes(containingType);
+                    while (baseTypes.length) {
+                        var baseType = baseTypes[0];
+                        if (modifiers & 16 /* Protected */ &&
+                            baseType.symbol === declaration.parent.symbol) {
+                            return true;
+                        }
+                        baseTypes = getBaseTypes(baseType);
+                    }
+                }
+                if (modifiers & 8 /* Private */) {
+                    error(node, ts.Diagnostics.Constructor_of_class_0_is_private_and_only_accessible_within_the_class_declaration, typeToString(declaringClass));
+                }
+                if (modifiers & 16 /* Protected */) {
+                    error(node, ts.Diagnostics.Constructor_of_class_0_is_protected_and_only_accessible_within_the_class_declaration, typeToString(declaringClass));
+                }
+                return false;
+            }
+            return true;
+        }
+        function invocationError(node, apparentType, kind) {
+            error(node, kind === 0 /* Call */
+                ? ts.Diagnostics.Cannot_invoke_an_expression_whose_type_lacks_a_call_signature_Type_0_has_no_compatible_call_signatures
+                : ts.Diagnostics.Cannot_use_new_with_an_expression_whose_type_lacks_a_call_or_construct_signature, typeToString(apparentType));
+            invocationErrorRecovery(apparentType, kind);
+        }
+        function invocationErrorRecovery(apparentType, kind) {
+            if (!apparentType.symbol) {
+                return;
+            }
+            var importNode = getSymbolLinks(apparentType.symbol).originatingImport;
+            // Create a diagnostic on the originating import if possible onto which we can attach a quickfix
+            //  An import call expression cannot be rewritten into another form to correct the error - the only solution is to use `.default` at the use-site
+            if (importNode && !ts.isImportCall(importNode)) {
+                var sigs = getSignaturesOfType(getTypeOfSymbol(getSymbolLinks(apparentType.symbol).target), kind);
+                if (!sigs || !sigs.length)
+                    return;
+                error(importNode, ts.Diagnostics.A_namespace_style_import_cannot_be_called_or_constructed_and_will_cause_a_failure_at_runtime);
+            }
+        }
+        function resolveTaggedTemplateExpression(node, candidatesOutArray) {
+            var tagType = checkExpression(node.tag);
+            var apparentType = getApparentType(tagType);
+            if (apparentType === errorType) {
+                // Another error has already been reported
+                return resolveErrorCall(node);
+            }
+            var callSignatures = getSignaturesOfType(apparentType, 0 /* Call */);
+            var constructSignatures = getSignaturesOfType(apparentType, 1 /* Construct */);
+            if (isUntypedFunctionCall(tagType, apparentType, callSignatures.length, constructSignatures.length)) {
+                return resolveUntypedCall(node);
+            }
+            if (!callSignatures.length) {
+                invocationError(node, apparentType, 0 /* Call */);
+                return resolveErrorCall(node);
+            }
+            return resolveCall(node, callSignatures, candidatesOutArray);
+        }
+        /**
+         * Gets the localized diagnostic head message to use for errors when resolving a decorator as a call expression.
+         */
+        function getDiagnosticHeadMessageForDecoratorResolution(node) {
+            switch (node.parent.kind) {
+                case 235 /* ClassDeclaration */:
+                case 205 /* ClassExpression */:
+                    return ts.Diagnostics.Unable_to_resolve_signature_of_class_decorator_when_called_as_an_expression;
+                case 149 /* Parameter */:
+                    return ts.Diagnostics.Unable_to_resolve_signature_of_parameter_decorator_when_called_as_an_expression;
+                case 152 /* PropertyDeclaration */:
+                    return ts.Diagnostics.Unable_to_resolve_signature_of_property_decorator_when_called_as_an_expression;
+                case 154 /* MethodDeclaration */:
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                    return ts.Diagnostics.Unable_to_resolve_signature_of_method_decorator_when_called_as_an_expression;
+                default:
+                    return ts.Debug.fail();
+            }
+        }
+        /**
+         * Resolves a decorator as if it were a call expression.
+         */
+        function resolveDecorator(node, candidatesOutArray) {
+            var funcType = checkExpression(node.expression);
+            var apparentType = getApparentType(funcType);
+            if (apparentType === errorType) {
+                return resolveErrorCall(node);
+            }
+            var callSignatures = getSignaturesOfType(apparentType, 0 /* Call */);
+            var constructSignatures = getSignaturesOfType(apparentType, 1 /* Construct */);
+            if (isUntypedFunctionCall(funcType, apparentType, callSignatures.length, constructSignatures.length)) {
+                return resolveUntypedCall(node);
+            }
+            if (isPotentiallyUncalledDecorator(node, callSignatures)) {
+                var nodeStr = ts.getTextOfNode(node.expression, /*includeTrivia*/ false);
+                error(node, ts.Diagnostics._0_accepts_too_few_arguments_to_be_used_as_a_decorator_here_Did_you_mean_to_call_it_first_and_write_0, nodeStr);
+                return resolveErrorCall(node);
+            }
+            var headMessage = getDiagnosticHeadMessageForDecoratorResolution(node);
+            if (!callSignatures.length) {
+                var errorInfo = ts.chainDiagnosticMessages(/*details*/ undefined, ts.Diagnostics.Cannot_invoke_an_expression_whose_type_lacks_a_call_signature_Type_0_has_no_compatible_call_signatures, typeToString(apparentType));
+                errorInfo = ts.chainDiagnosticMessages(errorInfo, headMessage);
+                diagnostics.add(ts.createDiagnosticForNodeFromMessageChain(node, errorInfo));
+                invocationErrorRecovery(apparentType, 0 /* Call */);
+                return resolveErrorCall(node);
+            }
+            return resolveCall(node, callSignatures, candidatesOutArray, headMessage);
+        }
+        /**
+         * Sometimes, we have a decorator that could accept zero arguments,
+         * but is receiving too many arguments as part of the decorator invocation.
+         * In those cases, a user may have meant to *call* the expression before using it as a decorator.
+         */
+        function isPotentiallyUncalledDecorator(decorator, signatures) {
+            return signatures.length && ts.every(signatures, function (signature) {
+                return signature.minArgumentCount === 0 &&
+                    !signature.hasRestParameter &&
+                    signature.parameters.length < getEffectiveArgumentCount(decorator, /*args*/ undefined, signature);
+            });
+        }
+        /**
+         * This function is similar to getResolvedSignature but is exclusively for trying to resolve JSX stateless-function component.
+         * The main reason we have to use this function instead of getResolvedSignature because, the caller of this function will already check the type of openingLikeElement's tagName
+         * and pass the type as elementType. The elementType can not be a union (as such case should be handled by the caller of this function)
+         * Note: at this point, we are still not sure whether the opening-like element is a stateless function component or not.
+         * @param openingLikeElement an opening-like JSX element to try to resolve as JSX stateless function
+         * @param elementType an element type of the opneing-like element by checking opening-like element's tagname.
+         * @param candidatesOutArray an array of signature to be filled in by the function. It is passed by signature help in the language service;
+         *                           the function will fill it up with appropriate candidate signatures
+         */
+        function getResolvedJsxStatelessFunctionSignature(openingLikeElement, elementType, candidatesOutArray) {
+            ts.Debug.assert(!(elementType.flags & 262144 /* Union */));
+            var callSignatures = elementType && getSignaturesOfType(elementType, 0 /* Call */);
+            if (callSignatures && callSignatures.length > 0) {
+                return resolveCall(openingLikeElement, callSignatures, candidatesOutArray);
+            }
+            return undefined;
+        }
+        function resolveSignature(node, candidatesOutArray) {
+            switch (node.kind) {
+                case 187 /* CallExpression */:
+                    return resolveCallExpression(node, candidatesOutArray);
+                case 188 /* NewExpression */:
+                    return resolveNewExpression(node, candidatesOutArray);
+                case 189 /* TaggedTemplateExpression */:
+                    return resolveTaggedTemplateExpression(node, candidatesOutArray);
+                case 150 /* Decorator */:
+                    return resolveDecorator(node, candidatesOutArray);
+                case 257 /* JsxOpeningElement */:
+                case 256 /* JsxSelfClosingElement */:
+                    // This code-path is called by language service
+                    var exprTypes = checkExpression(node.tagName);
+                    return forEachType(exprTypes, function (exprType) {
+                        var sfcResult = getResolvedJsxStatelessFunctionSignature(node, exprType, candidatesOutArray);
+                        if (sfcResult && sfcResult !== unknownSignature) {
+                            return sfcResult;
+                        }
+                        var sigs = getInstantiatedJsxSignatures(node, exprType);
+                        if (candidatesOutArray && ts.length(sigs)) {
+                            candidatesOutArray.push.apply(candidatesOutArray, sigs);
+                        }
+                        return ts.length(sigs) ? sigs[0] : unknownSignature;
+                    }) || unknownSignature;
+            }
+            throw ts.Debug.assertNever(node, "Branch in 'resolveSignature' should be unreachable.");
+        }
+        /**
+         * Resolve a signature of a given call-like expression.
+         * @param node a call-like expression to try resolve a signature for
+         * @param candidatesOutArray an array of signature to be filled in by the function. It is passed by signature help in the language service;
+         *                           the function will fill it up with appropriate candidate signatures
+         * @return a signature of the call-like expression or undefined if one can't be found
+         */
+        function getResolvedSignature(node, candidatesOutArray) {
+            var links = getNodeLinks(node);
+            // If getResolvedSignature has already been called, we will have cached the resolvedSignature.
+            // However, it is possible that either candidatesOutArray was not passed in the first time,
+            // or that a different candidatesOutArray was passed in. Therefore, we need to redo the work
+            // to correctly fill the candidatesOutArray.
+            var cached = links.resolvedSignature;
+            if (cached && cached !== resolvingSignature && !candidatesOutArray) {
+                return cached;
+            }
+            links.resolvedSignature = resolvingSignature;
+            var result = resolveSignature(node, candidatesOutArray);
+            // If signature resolution originated in control flow type analysis (for example to compute the
+            // assigned type in a flow assignment) we don't cache the result as it may be based on temporary
+            // types from the control flow analysis.
+            links.resolvedSignature = flowLoopStart === flowLoopCount ? result : cached;
+            return result;
+        }
+        /**
+         * Indicates whether a declaration can be treated as a constructor in a JavaScript
+         * file.
+         */
+        function isJavaScriptConstructor(node) {
+            if (node && ts.isInJavaScriptFile(node)) {
+                // If the node has a @class tag, treat it like a constructor.
+                if (ts.getJSDocClassTag(node))
+                    return true;
+                // If the symbol of the node has members, treat it like a constructor.
+                var symbol = ts.isFunctionDeclaration(node) || ts.isFunctionExpression(node) ? getSymbolOfNode(node) :
+                    ts.isVariableDeclaration(node) && node.initializer && ts.isFunctionExpression(node.initializer) ? getSymbolOfNode(node.initializer) :
+                        undefined;
+                return !!symbol && symbol.members !== undefined;
+            }
+            return false;
+        }
+        function getJavaScriptClassType(symbol) {
+            var inferred;
+            if (isJavaScriptConstructor(symbol.valueDeclaration)) {
+                inferred = getInferredClassType(symbol);
+            }
+            var assigned = getAssignedClassType(symbol);
+            var valueType = getTypeOfSymbol(symbol);
+            if (valueType.symbol && !isInferredClassType(valueType) && isJavaScriptConstructor(valueType.symbol.valueDeclaration)) {
+                inferred = getInferredClassType(valueType.symbol);
+            }
+            return assigned && inferred ?
+                getIntersectionType([inferred, assigned]) :
+                assigned || inferred;
+        }
+        function getAssignedClassType(symbol) {
+            var decl = symbol.valueDeclaration;
+            var assignmentSymbol = decl && decl.parent &&
+                (ts.isBinaryExpression(decl.parent) && getSymbolOfNode(decl.parent.left) ||
+                    ts.isVariableDeclaration(decl.parent) && getSymbolOfNode(decl.parent));
+            if (assignmentSymbol) {
+                var prototype = ts.forEach(assignmentSymbol.declarations, getAssignedJavascriptPrototype);
+                if (prototype) {
+                    return checkExpression(prototype);
+                }
+            }
+        }
+        function getAssignedJavascriptPrototype(node) {
+            if (!node.parent) {
+                return false;
+            }
+            var parent = node.parent;
+            while (parent && parent.kind === 185 /* PropertyAccessExpression */) {
+                parent = parent.parent;
+            }
+            if (parent && ts.isBinaryExpression(parent) && ts.isPrototypeAccess(parent.left) && parent.operatorToken.kind === 58 /* EqualsToken */) {
+                var right = ts.getInitializerOfBinaryExpression(parent);
+                return ts.isObjectLiteralExpression(right) && right;
+            }
+        }
+        function getInferredClassType(symbol) {
+            var links = getSymbolLinks(symbol);
+            if (!links.inferredClassType) {
+                links.inferredClassType = createAnonymousType(symbol, getMembersOfSymbol(symbol) || emptySymbols, ts.emptyArray, ts.emptyArray, /*stringIndexType*/ undefined, /*numberIndexType*/ undefined);
+            }
+            return links.inferredClassType;
+        }
+        function isInferredClassType(type) {
+            return type.symbol
+                && ts.getObjectFlags(type) & 16 /* Anonymous */
+                && getSymbolLinks(type.symbol).inferredClassType === type;
+        }
+        /**
+         * Syntactically and semantically checks a call or new expression.
+         * @param node The call/new expression to be checked.
+         * @returns On success, the expression's signature's return type. On failure, anyType.
+         */
+        function checkCallExpression(node) {
+            if (!checkGrammarTypeArguments(node, node.typeArguments))
+                checkGrammarArguments(node.arguments);
+            var signature = getResolvedSignature(node);
+            if (node.expression.kind === 97 /* SuperKeyword */) {
+                return voidType;
+            }
+            if (node.kind === 188 /* NewExpression */) {
+                var declaration = signature.declaration;
+                if (declaration &&
+                    declaration.kind !== 155 /* Constructor */ &&
+                    declaration.kind !== 159 /* ConstructSignature */ &&
+                    declaration.kind !== 164 /* ConstructorType */ &&
+                    !ts.isJSDocConstructSignature(declaration)) {
+                    // When resolved signature is a call signature (and not a construct signature) the result type is any, unless
+                    // the declaring function had members created through 'x.prototype.y = expr' or 'this.y = expr' psuedodeclarations
+                    // in a JS file
+                    // Note:JS inferred classes might come from a variable declaration instead of a function declaration.
+                    // In this case, using getResolvedSymbol directly is required to avoid losing the members from the declaration.
+                    var funcSymbol = checkExpression(node.expression).symbol;
+                    if (!funcSymbol && node.expression.kind === 71 /* Identifier */) {
+                        funcSymbol = getResolvedSymbol(node.expression);
+                    }
+                    var type = funcSymbol && getJavaScriptClassType(funcSymbol);
+                    if (type) {
+                        return signature.target ? instantiateType(type, signature.mapper) : type;
+                    }
+                    if (noImplicitAny) {
+                        error(node, ts.Diagnostics.new_expression_whose_target_lacks_a_construct_signature_implicitly_has_an_any_type);
+                    }
+                    return anyType;
+                }
+            }
+            // In JavaScript files, calls to any identifier 'require' are treated as external module imports
+            if (ts.isInJavaScriptFile(node) && isCommonJsRequire(node)) {
+                return resolveExternalModuleTypeByLiteral(node.arguments[0]);
+            }
+            var returnType = getReturnTypeOfSignature(signature);
+            // Treat any call to the global 'Symbol' function that is part of a const variable or readonly property
+            // as a fresh unique symbol literal type.
+            if (returnType.flags & 3072 /* ESSymbolLike */ && isSymbolOrSymbolForCall(node)) {
+                return getESSymbolLikeTypeForNode(ts.walkUpParenthesizedExpressions(node.parent));
+            }
+            var jsAssignmentType;
+            if (ts.isInJavaScriptFile(node)) {
+                var decl = ts.getDeclarationOfJSInitializer(node);
+                if (decl) {
+                    var jsSymbol = getSymbolOfNode(decl);
+                    if (jsSymbol && ts.hasEntries(jsSymbol.exports)) {
+                        jsAssignmentType = createAnonymousType(jsSymbol, jsSymbol.exports, ts.emptyArray, ts.emptyArray, jsObjectLiteralIndexInfo, undefined);
+                    }
+                }
+            }
+            return jsAssignmentType ? getIntersectionType([returnType, jsAssignmentType]) : returnType;
+        }
+        function isSymbolOrSymbolForCall(node) {
+            if (!ts.isCallExpression(node))
+                return false;
+            var left = node.expression;
+            if (ts.isPropertyAccessExpression(left) && left.name.escapedText === "for") {
+                left = left.expression;
+            }
+            if (!ts.isIdentifier(left) || left.escapedText !== "Symbol") {
+                return false;
+            }
+            // make sure `Symbol` is the global symbol
+            var globalESSymbol = getGlobalESSymbolConstructorSymbol(/*reportErrors*/ false);
+            if (!globalESSymbol) {
+                return false;
+            }
+            return globalESSymbol === resolveName(left, "Symbol", 67216319 /* Value */, /*nameNotFoundMessage*/ undefined, /*nameArg*/ undefined, /*isUse*/ false);
+        }
+        function checkImportCallExpression(node) {
+            // Check grammar of dynamic import
+            if (!checkGrammarArguments(node.arguments))
+                checkGrammarImportCallExpression(node);
+            if (node.arguments.length === 0) {
+                return createPromiseReturnType(node, anyType);
+            }
+            var specifier = node.arguments[0];
+            var specifierType = checkExpressionCached(specifier);
+            // Even though multiple arugments is grammatically incorrect, type-check extra arguments for completion
+            for (var i = 1; i < node.arguments.length; ++i) {
+                checkExpressionCached(node.arguments[i]);
+            }
+            if (specifierType.flags & 8192 /* Undefined */ || specifierType.flags & 16384 /* Null */ || !isTypeAssignableTo(specifierType, stringType)) {
+                error(specifier, ts.Diagnostics.Dynamic_import_s_specifier_must_be_of_type_string_but_here_has_type_0, typeToString(specifierType));
+            }
+            // resolveExternalModuleName will return undefined if the moduleReferenceExpression is not a string literal
+            var moduleSymbol = resolveExternalModuleName(node, specifier);
+            if (moduleSymbol) {
+                var esModuleSymbol = resolveESModuleSymbol(moduleSymbol, specifier, /*dontRecursivelyResolve*/ true);
+                if (esModuleSymbol) {
+                    return createPromiseReturnType(node, getTypeWithSyntheticDefaultImportType(getTypeOfSymbol(esModuleSymbol), esModuleSymbol, moduleSymbol));
+                }
+            }
+            return createPromiseReturnType(node, anyType);
+        }
+        function getTypeWithSyntheticDefaultImportType(type, symbol, originalSymbol) {
+            if (allowSyntheticDefaultImports && type && type !== errorType) {
+                var synthType = type;
+                if (!synthType.syntheticType) {
+                    var file = ts.find(originalSymbol.declarations, ts.isSourceFile);
+                    var hasSyntheticDefault = canHaveSyntheticDefault(file, originalSymbol, /*dontResolveAlias*/ false);
+                    if (hasSyntheticDefault) {
+                        var memberTable = ts.createSymbolTable();
+                        var newSymbol = createSymbol(2097152 /* Alias */, "default" /* Default */);
+                        newSymbol.target = resolveSymbol(symbol);
+                        memberTable.set("default" /* Default */, newSymbol);
+                        var anonymousSymbol = createSymbol(2048 /* TypeLiteral */, "__type" /* Type */);
+                        var defaultContainingObject = createAnonymousType(anonymousSymbol, memberTable, ts.emptyArray, ts.emptyArray, /*stringIndexInfo*/ undefined, /*numberIndexInfo*/ undefined);
+                        anonymousSymbol.type = defaultContainingObject;
+                        synthType.syntheticType = isValidSpreadType(type) ? getSpreadType(type, defaultContainingObject, anonymousSymbol, /*typeFLags*/ 0, /*objectFlags*/ 0) : defaultContainingObject;
+                    }
+                    else {
+                        synthType.syntheticType = type;
+                    }
+                }
+                return synthType.syntheticType;
+            }
+            return type;
+        }
+        function isCommonJsRequire(node) {
+            if (!ts.isRequireCall(node, /*checkArgumentIsStringLiteralLike*/ true)) {
+                return false;
+            }
+            // Make sure require is not a local function
+            if (!ts.isIdentifier(node.expression))
+                return ts.Debug.fail();
+            var resolvedRequire = resolveName(node.expression, node.expression.escapedText, 67216319 /* Value */, /*nameNotFoundMessage*/ undefined, /*nameArg*/ undefined, /*isUse*/ true); // TODO: GH#18217
+            if (resolvedRequire === requireSymbol) {
+                return true;
+            }
+            // project includes symbol named 'require' - make sure that it is ambient and local non-alias
+            if (resolvedRequire.flags & 2097152 /* Alias */) {
+                return false;
+            }
+            var targetDeclarationKind = resolvedRequire.flags & 16 /* Function */
+                ? 234 /* FunctionDeclaration */
+                : resolvedRequire.flags & 3 /* Variable */
+                    ? 232 /* VariableDeclaration */
+                    : 0 /* Unknown */;
+            if (targetDeclarationKind !== 0 /* Unknown */) {
+                var decl = ts.getDeclarationOfKind(resolvedRequire, targetDeclarationKind);
+                // function/variable declaration should be ambient
+                return !!decl && !!(decl.flags & 4194304 /* Ambient */);
+            }
+            return false;
+        }
+        function checkTaggedTemplateExpression(node) {
+            checkGrammarTypeArguments(node, node.typeArguments);
+            if (languageVersion < 2 /* ES2015 */) {
+                checkExternalEmitHelpers(node, 65536 /* MakeTemplateObject */);
+            }
+            return getReturnTypeOfSignature(getResolvedSignature(node));
+        }
+        function checkAssertion(node) {
+            return checkAssertionWorker(node, node.type, node.expression);
+        }
+        function checkAssertionWorker(errNode, type, expression, checkMode) {
+            var exprType = getRegularTypeOfObjectLiteral(getBaseTypeOfLiteralType(checkExpression(expression, checkMode)));
+            checkSourceElement(type);
+            var targetType = getTypeFromTypeNode(type);
+            if (produceDiagnostics && targetType !== errorType) {
+                var widenedType = getWidenedType(exprType);
+                if (!isTypeComparableTo(targetType, widenedType)) {
+                    checkTypeComparableTo(exprType, targetType, errNode, ts.Diagnostics.Type_0_cannot_be_converted_to_type_1);
+                }
+            }
+            return targetType;
+        }
+        function checkNonNullAssertion(node) {
+            return getNonNullableType(checkExpression(node.expression));
+        }
+        function checkMetaProperty(node) {
+            checkGrammarMetaProperty(node);
+            if (node.keywordToken === 94 /* NewKeyword */) {
+                return checkNewTargetMetaProperty(node);
+            }
+            if (node.keywordToken === 91 /* ImportKeyword */) {
+                return checkImportMetaProperty(node);
+            }
+            return ts.Debug.assertNever(node.keywordToken);
+        }
+        function checkNewTargetMetaProperty(node) {
+            var container = ts.getNewTargetContainer(node);
+            if (!container) {
+                error(node, ts.Diagnostics.Meta_property_0_is_only_allowed_in_the_body_of_a_function_declaration_function_expression_or_constructor, "new.target");
+                return errorType;
+            }
+            else if (container.kind === 155 /* Constructor */) {
+                var symbol = getSymbolOfNode(container.parent);
+                return getTypeOfSymbol(symbol);
+            }
+            else {
+                var symbol = getSymbolOfNode(container);
+                return getTypeOfSymbol(symbol);
+            }
+        }
+        function checkImportMetaProperty(node) {
+            if (languageVersion < 6 /* ESNext */ || moduleKind < ts.ModuleKind.ESNext) {
+                error(node, ts.Diagnostics.The_import_meta_meta_property_is_only_allowed_using_ESNext_for_the_target_and_module_compiler_options);
+            }
+            var file = ts.getSourceFileOfNode(node);
+            ts.Debug.assert(!!(file.flags & 1048576 /* PossiblyContainsImportMeta */), "Containing file is missing import meta node flag.");
+            ts.Debug.assert(!!file.externalModuleIndicator, "Containing file should be a module.");
+            return node.name.escapedText === "meta" ? getGlobalImportMetaType() : errorType;
+        }
+        function getTypeOfParameter(symbol) {
+            var type = getTypeOfSymbol(symbol);
+            if (strictNullChecks) {
+                var declaration = symbol.valueDeclaration;
+                if (declaration && ts.hasInitializer(declaration)) {
+                    return getOptionalType(type);
+                }
+            }
+            return type;
+        }
+        function getTypeAtPosition(signature, pos) {
+            return signature.hasRestParameter ?
+                pos < signature.parameters.length - 1 ? getTypeOfParameter(signature.parameters[pos]) : getRestTypeOfSignature(signature) :
+                pos < signature.parameters.length ? getTypeOfParameter(signature.parameters[pos]) : anyType;
+        }
+        function getTypeOfFirstParameterOfSignature(signature) {
+            return getTypeOfFirstParameterOfSignatureWithFallback(signature, neverType);
+        }
+        function getTypeOfFirstParameterOfSignatureWithFallback(signature, fallbackType) {
+            return signature.parameters.length > 0 ? getTypeAtPosition(signature, 0) : fallbackType;
+        }
+        function inferFromAnnotatedParameters(signature, context, mapper) {
+            var len = signature.parameters.length - (signature.hasRestParameter ? 1 : 0);
+            for (var i = 0; i < len; i++) {
+                var declaration = signature.parameters[i].valueDeclaration;
+                if (declaration.type) {
+                    var typeNode = ts.getEffectiveTypeAnnotationNode(declaration);
+                    if (typeNode) {
+                        inferTypes(mapper.inferences, getTypeFromTypeNode(typeNode), getTypeAtPosition(context, i));
+                    }
+                }
+            }
+        }
+        function assignContextualParameterTypes(signature, context) {
+            signature.typeParameters = context.typeParameters;
+            if (context.thisParameter) {
+                var parameter = signature.thisParameter;
+                if (!parameter || parameter.valueDeclaration && !parameter.valueDeclaration.type) {
+                    if (!parameter) {
+                        signature.thisParameter = createSymbolWithType(context.thisParameter, /*type*/ undefined);
+                    }
+                    assignTypeToParameterAndFixTypeParameters(signature.thisParameter, getTypeOfSymbol(context.thisParameter));
+                }
+            }
+            var len = signature.parameters.length - (signature.hasRestParameter ? 1 : 0);
+            for (var i = 0; i < len; i++) {
+                var parameter = signature.parameters[i];
+                if (!ts.getEffectiveTypeAnnotationNode(parameter.valueDeclaration)) {
+                    var contextualParameterType = getTypeAtPosition(context, i);
+                    assignTypeToParameterAndFixTypeParameters(parameter, contextualParameterType);
+                }
+            }
+            if (signature.hasRestParameter && isRestParameterIndex(context, signature.parameters.length - 1)) {
+                // parameter might be a transient symbol generated by use of `arguments` in the function body.
+                var parameter = ts.last(signature.parameters);
+                if (isTransientSymbol(parameter) || !ts.getEffectiveTypeAnnotationNode(parameter.valueDeclaration)) {
+                    var contextualParameterType = getTypeOfSymbol(ts.last(context.parameters));
+                    assignTypeToParameterAndFixTypeParameters(parameter, contextualParameterType);
+                }
+            }
+        }
+        // When contextual typing assigns a type to a parameter that contains a binding pattern, we also need to push
+        // the destructured type into the contained binding elements.
+        function assignBindingElementTypes(pattern) {
+            for (var _i = 0, _a = pattern.elements; _i < _a.length; _i++) {
+                var element = _a[_i];
+                if (!ts.isOmittedExpression(element)) {
+                    if (element.name.kind === 71 /* Identifier */) {
+                        getSymbolLinks(getSymbolOfNode(element)).type = getTypeForBindingElement(element);
+                    }
+                    else {
+                        assignBindingElementTypes(element.name);
+                    }
+                }
+            }
+        }
+        function assignTypeToParameterAndFixTypeParameters(parameter, contextualType) {
+            var links = getSymbolLinks(parameter);
+            if (!links.type) {
+                links.type = contextualType;
+                var decl = parameter.valueDeclaration;
+                if (decl.name.kind !== 71 /* Identifier */) {
+                    // if inference didn't come up with anything but {}, fall back to the binding pattern if present.
+                    if (links.type === emptyObjectType) {
+                        links.type = getTypeFromBindingPattern(decl.name);
+                    }
+                    assignBindingElementTypes(decl.name);
+                }
+            }
+        }
+        function createPromiseType(promisedType) {
+            // creates a `Promise<T>` type where `T` is the promisedType argument
+            var globalPromiseType = getGlobalPromiseType(/*reportErrors*/ true);
+            if (globalPromiseType !== emptyGenericType) {
+                // if the promised type is itself a promise, get the underlying type; otherwise, fallback to the promised type
+                promisedType = getAwaitedType(promisedType) || emptyObjectType;
+                return createTypeReference(globalPromiseType, [promisedType]);
+            }
+            return emptyObjectType;
+        }
+        function createPromiseReturnType(func, promisedType) {
+            var promiseType = createPromiseType(promisedType);
+            if (promiseType === emptyObjectType) {
+                error(func, ts.isImportCall(func) ?
+                    ts.Diagnostics.A_dynamic_import_call_returns_a_Promise_Make_sure_you_have_a_declaration_for_Promise_or_include_ES2015_in_your_lib_option :
+                    ts.Diagnostics.An_async_function_or_method_must_return_a_Promise_Make_sure_you_have_a_declaration_for_Promise_or_include_ES2015_in_your_lib_option);
+                return errorType;
+            }
+            else if (!getGlobalPromiseConstructorSymbol(/*reportErrors*/ true)) {
+                error(func, ts.isImportCall(func) ?
+                    ts.Diagnostics.A_dynamic_import_call_in_ES5_SlashES3_requires_the_Promise_constructor_Make_sure_you_have_a_declaration_for_the_Promise_constructor_or_include_ES2015_in_your_lib_option :
+                    ts.Diagnostics.An_async_function_or_method_in_ES5_SlashES3_requires_the_Promise_constructor_Make_sure_you_have_a_declaration_for_the_Promise_constructor_or_include_ES2015_in_your_lib_option);
+            }
+            return promiseType;
+        }
+        function getReturnTypeFromBody(func, checkMode) {
+            if (!func.body) {
+                return errorType;
+            }
+            var functionFlags = ts.getFunctionFlags(func);
+            var type;
+            if (func.body.kind !== 213 /* Block */) {
+                type = checkExpressionCached(func.body, checkMode);
+                if (functionFlags & 2 /* Async */) {
+                    // From within an async function you can return either a non-promise value or a promise. Any
+                    // Promise/A+ compatible implementation will always assimilate any foreign promise, so the
+                    // return type of the body should be unwrapped to its awaited type, which we will wrap in
+                    // the native Promise<T> type later in this function.
+                    type = checkAwaitedType(type, /*errorNode*/ func, ts.Diagnostics.The_return_type_of_an_async_function_must_either_be_a_valid_promise_or_must_not_contain_a_callable_then_member);
+                }
+            }
+            else {
+                var types = checkAndAggregateReturnExpressionTypes(func, checkMode);
+                if (functionFlags & 1 /* Generator */) { // Generator or AsyncGenerator function
+                    types = ts.concatenate(checkAndAggregateYieldOperandTypes(func, checkMode), types);
+                    if (!types || types.length === 0) {
+                        var iterableIteratorAny = functionFlags & 2 /* Async */
+                            ? createAsyncIterableIteratorType(anyType) // AsyncGenerator function
+                            : createIterableIteratorType(anyType); // Generator function
+                        if (noImplicitAny) {
+                            error(func.asteriskToken, ts.Diagnostics.Generator_implicitly_has_type_0_because_it_does_not_yield_any_values_Consider_supplying_a_return_type, typeToString(iterableIteratorAny));
+                        }
+                        return iterableIteratorAny;
+                    }
+                }
+                else {
+                    if (!types) {
+                        // For an async function, the return type will not be never, but rather a Promise for never.
+                        return functionFlags & 2 /* Async */
+                            ? createPromiseReturnType(func, neverType) // Async function
+                            : neverType; // Normal function
+                    }
+                    if (types.length === 0) {
+                        // For an async function, the return type will not be void, but rather a Promise for void.
+                        return functionFlags & 2 /* Async */
+                            ? createPromiseReturnType(func, voidType) // Async function
+                            : voidType; // Normal function
+                    }
+                }
+                // Return a union of the return expression types.
+                type = getUnionType(types, 2 /* Subtype */);
+            }
+            var contextualSignature = getContextualSignatureForFunctionLikeDeclaration(func);
+            if (!contextualSignature) {
+                reportErrorsFromWidening(func, type);
+            }
+            if (isUnitType(type)) {
+                var contextualType = !contextualSignature ? undefined :
+                    contextualSignature === getSignatureFromDeclaration(func) ? type :
+                        getReturnTypeOfSignature(contextualSignature);
+                if (contextualType) {
+                    switch (functionFlags & 3 /* AsyncGenerator */) {
+                        case 3 /* AsyncGenerator */:
+                            contextualType = getIteratedTypeOfGenerator(contextualType, /*isAsyncGenerator*/ true);
+                            break;
+                        case 1 /* Generator */:
+                            contextualType = getIteratedTypeOfGenerator(contextualType, /*isAsyncGenerator*/ false);
+                            break;
+                        case 2 /* Async */:
+                            contextualType = getPromisedTypeOfPromise(contextualType);
+                            break;
+                    }
+                }
+                type = getWidenedLiteralLikeTypeForContextualType(type, contextualType);
+            }
+            var widenedType = getWidenedType(type);
+            switch (functionFlags & 3 /* AsyncGenerator */) {
+                case 3 /* AsyncGenerator */:
+                    return createAsyncIterableIteratorType(widenedType);
+                case 1 /* Generator */:
+                    return createIterableIteratorType(widenedType);
+                case 2 /* Async */:
+                    // From within an async function you can return either a non-promise value or a promise. Any
+                    // Promise/A+ compatible implementation will always assimilate any foreign promise, so the
+                    // return type of the body is awaited type of the body, wrapped in a native Promise<T> type.
+                    return createPromiseType(widenedType);
+                default:
+                    return widenedType;
+            }
+        }
+        function checkAndAggregateYieldOperandTypes(func, checkMode) {
+            var aggregatedTypes = [];
+            var isAsync = (ts.getFunctionFlags(func) & 2 /* Async */) !== 0;
+            ts.forEachYieldExpression(func.body, function (yieldExpression) {
+                ts.pushIfUnique(aggregatedTypes, getYieldedTypeOfYieldExpression(yieldExpression, isAsync, checkMode));
+            });
+            return aggregatedTypes;
+        }
+        function getYieldedTypeOfYieldExpression(node, isAsync, checkMode) {
+            var errorNode = node.expression || node;
+            var expressionType = node.expression ? checkExpressionCached(node.expression, checkMode) : undefinedWideningType;
+            // A `yield*` expression effectively yields everything that its operand yields
+            var yieldedType = node.asteriskToken ? checkIteratedTypeOrElementType(expressionType, errorNode, /*allowStringInput*/ false, isAsync) : expressionType;
+            return !isAsync ? yieldedType : getAwaitedType(yieldedType, errorNode, node.asteriskToken
+                ? ts.Diagnostics.Type_of_iterated_elements_of_a_yield_Asterisk_operand_must_either_be_a_valid_promise_or_must_not_contain_a_callable_then_member
+                : ts.Diagnostics.Type_of_yield_operand_in_an_async_generator_must_either_be_a_valid_promise_or_must_not_contain_a_callable_then_member);
+        }
+        function isExhaustiveSwitchStatement(node) {
+            if (!node.possiblyExhaustive) {
+                return false;
+            }
+            var type = getTypeOfExpression(node.expression);
+            if (!isLiteralType(type)) {
+                return false;
+            }
+            var switchTypes = getSwitchClauseTypes(node);
+            if (!switchTypes.length || ts.some(switchTypes, isNeitherUnitTypeNorNever)) {
+                return false;
+            }
+            return eachTypeContainedIn(mapType(type, getRegularTypeOfLiteralType), switchTypes);
+        }
+        function functionHasImplicitReturn(func) {
+            if (!(func.flags & 128 /* HasImplicitReturn */)) {
+                return false;
+            }
+            if (ts.some(func.body.statements, function (statement) { return statement.kind === 227 /* SwitchStatement */ && isExhaustiveSwitchStatement(statement); })) {
+                return false;
+            }
+            return true;
+        }
+        /** NOTE: Return value of `[]` means a different thing than `undefined`. `[]` means func returns `void`, `undefined` means it returns `never`. */
+        function checkAndAggregateReturnExpressionTypes(func, checkMode) {
+            var functionFlags = ts.getFunctionFlags(func);
+            var aggregatedTypes = [];
+            var hasReturnWithNoExpression = functionHasImplicitReturn(func);
+            var hasReturnOfTypeNever = false;
+            ts.forEachReturnStatement(func.body, function (returnStatement) {
+                var expr = returnStatement.expression;
+                if (expr) {
+                    var type = checkExpressionCached(expr, checkMode);
+                    if (functionFlags & 2 /* Async */) {
+                        // From within an async function you can return either a non-promise value or a promise. Any
+                        // Promise/A+ compatible implementation will always assimilate any foreign promise, so the
+                        // return type of the body should be unwrapped to its awaited type, which should be wrapped in
+                        // the native Promise<T> type by the caller.
+                        type = checkAwaitedType(type, func, ts.Diagnostics.The_return_type_of_an_async_function_must_either_be_a_valid_promise_or_must_not_contain_a_callable_then_member);
+                    }
+                    if (type.flags & 32768 /* Never */) {
+                        hasReturnOfTypeNever = true;
+                    }
+                    ts.pushIfUnique(aggregatedTypes, type);
+                }
+                else {
+                    hasReturnWithNoExpression = true;
+                }
+            });
+            if (aggregatedTypes.length === 0 && !hasReturnWithNoExpression && (hasReturnOfTypeNever || mayReturnNever(func))) {
+                return undefined;
+            }
+            if (strictNullChecks && aggregatedTypes.length && hasReturnWithNoExpression &&
+                !(isJavaScriptConstructor(func) && aggregatedTypes.some(function (t) { return t.symbol === func.symbol; }))) {
+                // Javascript "callable constructors", containing eg `if (!(this instanceof A)) return new A()` should not add undefined
+                ts.pushIfUnique(aggregatedTypes, undefinedType);
+            }
+            return aggregatedTypes;
+        }
+        function mayReturnNever(func) {
+            switch (func.kind) {
+                case 192 /* FunctionExpression */:
+                case 193 /* ArrowFunction */:
+                    return true;
+                case 154 /* MethodDeclaration */:
+                    return func.parent.kind === 184 /* ObjectLiteralExpression */;
+                default:
+                    return false;
+            }
+        }
+        /**
+         * TypeScript Specification 1.0 (6.3) - July 2014
+         *   An explicitly typed function whose return type isn't the Void type,
+         *   the Any type, or a union type containing the Void or Any type as a constituent
+         *   must have at least one return statement somewhere in its body.
+         *   An exception to this rule is if the function implementation consists of a single 'throw' statement.
+         *
+         * @param returnType - return type of the function, can be undefined if return type is not explicitly specified
+         */
+        function checkAllCodePathsInNonVoidFunctionReturnOrThrow(func, returnType) {
+            if (!produceDiagnostics) {
+                return;
+            }
+            // Functions with with an explicitly specified 'void' or 'any' return type don't need any return expressions.
+            if (returnType && maybeTypeOfKind(returnType, 3 /* AnyOrUnknown */ | 4096 /* Void */)) {
+                return;
+            }
+            // If all we have is a function signature, or an arrow function with an expression body, then there is nothing to check.
+            // also if HasImplicitReturn flag is not set this means that all codepaths in function body end with return or throw
+            if (func.kind === 153 /* MethodSignature */ || ts.nodeIsMissing(func.body) || func.body.kind !== 213 /* Block */ || !functionHasImplicitReturn(func)) {
+                return;
+            }
+            var hasExplicitReturn = func.flags & 256 /* HasExplicitReturn */;
+            if (returnType && returnType.flags & 32768 /* Never */) {
+                error(ts.getEffectiveReturnTypeNode(func), ts.Diagnostics.A_function_returning_never_cannot_have_a_reachable_end_point);
+            }
+            else if (returnType && !hasExplicitReturn) {
+                // minimal check: function has syntactic return type annotation and no explicit return statements in the body
+                // this function does not conform to the specification.
+                // NOTE: having returnType !== undefined is a precondition for entering this branch so func.type will always be present
+                error(ts.getEffectiveReturnTypeNode(func), ts.Diagnostics.A_function_whose_declared_type_is_neither_void_nor_any_must_return_a_value);
+            }
+            else if (returnType && strictNullChecks && !isTypeAssignableTo(undefinedType, returnType)) {
+                error(ts.getEffectiveReturnTypeNode(func), ts.Diagnostics.Function_lacks_ending_return_statement_and_return_type_does_not_include_undefined);
+            }
+            else if (compilerOptions.noImplicitReturns) {
+                if (!returnType) {
+                    // If return type annotation is omitted check if function has any explicit return statements.
+                    // If it does not have any - its inferred return type is void - don't do any checks.
+                    // Otherwise get inferred return type from function body and report error only if it is not void / anytype
+                    if (!hasExplicitReturn) {
+                        return;
+                    }
+                    var inferredReturnType = getReturnTypeOfSignature(getSignatureFromDeclaration(func));
+                    if (isUnwrappedReturnTypeVoidOrAny(func, inferredReturnType)) {
+                        return;
+                    }
+                }
+                error(ts.getEffectiveReturnTypeNode(func) || func, ts.Diagnostics.Not_all_code_paths_return_a_value);
+            }
+        }
+        function checkFunctionExpressionOrObjectLiteralMethod(node, checkMode) {
+            ts.Debug.assert(node.kind !== 154 /* MethodDeclaration */ || ts.isObjectLiteralMethod(node));
+            // The identityMapper object is used to indicate that function expressions are wildcards
+            if (checkMode === 1 /* SkipContextSensitive */ && isContextSensitive(node)) {
+                return anyFunctionType;
+            }
+            // Grammar checking
+            var hasGrammarError = checkGrammarFunctionLikeDeclaration(node);
+            if (!hasGrammarError && node.kind === 192 /* FunctionExpression */) {
+                checkGrammarForGenerator(node);
+            }
+            var links = getNodeLinks(node);
+            var type = getTypeOfSymbol(getMergedSymbol(node.symbol));
+            if (isTypeAny(type)) {
+                return type;
+            }
+            // Check if function expression is contextually typed and assign parameter types if so.
+            if (!(links.flags & 1024 /* ContextChecked */)) {
+                var contextualSignature = getContextualSignature(node);
+                // If a type check is started at a function expression that is an argument of a function call, obtaining the
+                // contextual type may recursively get back to here during overload resolution of the call. If so, we will have
+                // already assigned contextual types.
+                if (!(links.flags & 1024 /* ContextChecked */)) {
+                    links.flags |= 1024 /* ContextChecked */;
+                    if (contextualSignature) {
+                        var signature = getSignaturesOfType(type, 0 /* Call */)[0];
+                        if (isContextSensitive(node)) {
+                            var contextualMapper = getContextualMapper(node);
+                            if (checkMode === 2 /* Inferential */) {
+                                inferFromAnnotatedParameters(signature, contextualSignature, contextualMapper);
+                            }
+                            var instantiatedContextualSignature = contextualMapper === identityMapper ?
+                                contextualSignature : instantiateSignature(contextualSignature, contextualMapper);
+                            assignContextualParameterTypes(signature, instantiatedContextualSignature);
+                        }
+                        if (!ts.getEffectiveReturnTypeNode(node) && !signature.resolvedReturnType) {
+                            var returnType = getReturnTypeFromBody(node, checkMode);
+                            if (!signature.resolvedReturnType) {
+                                signature.resolvedReturnType = returnType;
+                            }
+                        }
+                    }
+                    checkSignatureDeclaration(node);
+                    checkNodeDeferred(node);
+                }
+            }
+            return type;
+        }
+        function checkFunctionExpressionOrObjectLiteralMethodDeferred(node) {
+            ts.Debug.assert(node.kind !== 154 /* MethodDeclaration */ || ts.isObjectLiteralMethod(node));
+            var functionFlags = ts.getFunctionFlags(node);
+            var returnTypeNode = ts.getEffectiveReturnTypeNode(node);
+            var returnOrPromisedType = returnTypeNode &&
+                ((functionFlags & 3 /* AsyncGenerator */) === 2 /* Async */ ?
+                    checkAsyncFunctionReturnType(node) : // Async function
+                    getTypeFromTypeNode(returnTypeNode)); // AsyncGenerator function, Generator function, or normal function
+            if ((functionFlags & 1 /* Generator */) === 0) { // Async function or normal function
+                // return is not necessary in the body of generators
+                checkAllCodePathsInNonVoidFunctionReturnOrThrow(node, returnOrPromisedType);
+            }
+            if (node.body) {
+                if (!returnTypeNode) {
+                    // There are some checks that are only performed in getReturnTypeFromBody, that may produce errors
+                    // we need. An example is the noImplicitAny errors resulting from widening the return expression
+                    // of a function. Because checking of function expression bodies is deferred, there was never an
+                    // appropriate time to do this during the main walk of the file (see the comment at the top of
+                    // checkFunctionExpressionBodies). So it must be done now.
+                    getReturnTypeOfSignature(getSignatureFromDeclaration(node));
+                }
+                if (node.body.kind === 213 /* Block */) {
+                    checkSourceElement(node.body);
+                }
+                else {
+                    // From within an async function you can return either a non-promise value or a promise. Any
+                    // Promise/A+ compatible implementation will always assimilate any foreign promise, so we
+                    // should not be checking assignability of a promise to the return type. Instead, we need to
+                    // check assignability of the awaited type of the expression body against the promised type of
+                    // its return type annotation.
+                    var exprType = checkExpression(node.body);
+                    if (returnOrPromisedType) {
+                        if ((functionFlags & 3 /* AsyncGenerator */) === 2 /* Async */) { // Async function
+                            var awaitedType = checkAwaitedType(exprType, node.body, ts.Diagnostics.The_return_type_of_an_async_function_must_either_be_a_valid_promise_or_must_not_contain_a_callable_then_member);
+                            checkTypeAssignableTo(awaitedType, returnOrPromisedType, node.body);
+                        }
+                        else { // Normal function
+                            checkTypeAssignableTo(exprType, returnOrPromisedType, node.body);
+                        }
+                    }
+                }
+            }
+        }
+        function checkArithmeticOperandType(operand, type, diagnostic) {
+            if (!isTypeAssignableToKind(type, 168 /* NumberLike */)) {
+                error(operand, diagnostic);
+                return false;
+            }
+            return true;
+        }
+        function isReadonlySymbol(symbol) {
+            // The following symbols are considered read-only:
+            // Properties with a 'readonly' modifier
+            // Variables declared with 'const'
+            // Get accessors without matching set accessors
+            // Enum members
+            // Unions and intersections of the above (unions and intersections eagerly set isReadonly on creation)
+            return !!(ts.getCheckFlags(symbol) & 8 /* Readonly */ ||
+                symbol.flags & 4 /* Property */ && ts.getDeclarationModifierFlagsFromSymbol(symbol) & 64 /* Readonly */ ||
+                symbol.flags & 3 /* Variable */ && getDeclarationNodeFlagsFromSymbol(symbol) & 2 /* Const */ ||
+                symbol.flags & 98304 /* Accessor */ && !(symbol.flags & 65536 /* SetAccessor */) ||
+                symbol.flags & 8 /* EnumMember */);
+        }
+        function isReferenceToReadonlyEntity(expr, symbol) {
+            if (isReadonlySymbol(symbol)) {
+                // Allow assignments to readonly properties within constructors of the same class declaration.
+                if (symbol.flags & 4 /* Property */ &&
+                    (expr.kind === 185 /* PropertyAccessExpression */ || expr.kind === 186 /* ElementAccessExpression */) &&
+                    expr.expression.kind === 99 /* ThisKeyword */) {
+                    // Look for if this is the constructor for the class that `symbol` is a property of.
+                    var func = ts.getContainingFunction(expr);
+                    if (!(func && func.kind === 155 /* Constructor */)) {
+                        return true;
+                    }
+                    // If func.parent is a class and symbol is a (readonly) property of that class, or
+                    // if func is a constructor and symbol is a (readonly) parameter property declared in it,
+                    // then symbol is writeable here.
+                    return !(func.parent === symbol.valueDeclaration.parent || func === symbol.valueDeclaration.parent);
+                }
+                return true;
+            }
+            return false;
+        }
+        function isReferenceThroughNamespaceImport(expr) {
+            if (expr.kind === 185 /* PropertyAccessExpression */ || expr.kind === 186 /* ElementAccessExpression */) {
+                var node = ts.skipParentheses(expr.expression);
+                if (node.kind === 71 /* Identifier */) {
+                    var symbol = getNodeLinks(node).resolvedSymbol;
+                    if (symbol.flags & 2097152 /* Alias */) {
+                        var declaration = getDeclarationOfAliasSymbol(symbol);
+                        return !!declaration && declaration.kind === 246 /* NamespaceImport */;
+                    }
+                }
+            }
+            return false;
+        }
+        function checkReferenceExpression(expr, invalidReferenceMessage) {
+            // References are combinations of identifiers, parentheses, and property accesses.
+            var node = ts.skipOuterExpressions(expr, 2 /* Assertions */ | 1 /* Parentheses */);
+            if (node.kind !== 71 /* Identifier */ && node.kind !== 185 /* PropertyAccessExpression */ && node.kind !== 186 /* ElementAccessExpression */) {
+                error(expr, invalidReferenceMessage);
+                return false;
+            }
+            return true;
+        }
+        function checkDeleteExpression(node) {
+            checkExpression(node.expression);
+            var expr = ts.skipParentheses(node.expression);
+            if (expr.kind !== 185 /* PropertyAccessExpression */ && expr.kind !== 186 /* ElementAccessExpression */) {
+                error(expr, ts.Diagnostics.The_operand_of_a_delete_operator_must_be_a_property_reference);
+                return booleanType;
+            }
+            var links = getNodeLinks(expr);
+            var symbol = getExportSymbolOfValueSymbolIfExported(links.resolvedSymbol);
+            if (symbol && isReadonlySymbol(symbol)) {
+                error(expr, ts.Diagnostics.The_operand_of_a_delete_operator_cannot_be_a_read_only_property);
+            }
+            return booleanType;
+        }
+        function checkTypeOfExpression(node) {
+            checkExpression(node.expression);
+            return typeofType;
+        }
+        function checkVoidExpression(node) {
+            checkExpression(node.expression);
+            return undefinedWideningType;
+        }
+        function checkAwaitExpression(node) {
+            // Grammar checking
+            if (produceDiagnostics) {
+                if (!(node.flags & 16384 /* AwaitContext */)) {
+                    grammarErrorOnFirstToken(node, ts.Diagnostics.await_expression_is_only_allowed_within_an_async_function);
+                }
+                if (isInParameterInitializerBeforeContainingFunction(node)) {
+                    error(node, ts.Diagnostics.await_expressions_cannot_be_used_in_a_parameter_initializer);
+                }
+            }
+            var operandType = checkExpression(node.expression);
+            return checkAwaitedType(operandType, node, ts.Diagnostics.Type_of_await_operand_must_either_be_a_valid_promise_or_must_not_contain_a_callable_then_member);
+        }
+        function checkPrefixUnaryExpression(node) {
+            var operandType = checkExpression(node.operand);
+            if (operandType === silentNeverType) {
+                return silentNeverType;
+            }
+            if (node.operand.kind === 8 /* NumericLiteral */) {
+                if (node.operator === 38 /* MinusToken */) {
+                    return getFreshTypeOfLiteralType(getLiteralType(-node.operand.text));
+                }
+                else if (node.operator === 37 /* PlusToken */) {
+                    return getFreshTypeOfLiteralType(getLiteralType(+node.operand.text));
+                }
+            }
+            switch (node.operator) {
+                case 37 /* PlusToken */:
+                case 38 /* MinusToken */:
+                case 52 /* TildeToken */:
+                    checkNonNullType(operandType, node.operand);
+                    if (maybeTypeOfKind(operandType, 3072 /* ESSymbolLike */)) {
+                        error(node.operand, ts.Diagnostics.The_0_operator_cannot_be_applied_to_type_symbol, ts.tokenToString(node.operator));
+                    }
+                    return numberType;
+                case 51 /* ExclamationToken */:
+                    var facts = getTypeFacts(operandType) & (1048576 /* Truthy */ | 2097152 /* Falsy */);
+                    return facts === 1048576 /* Truthy */ ? falseType :
+                        facts === 2097152 /* Falsy */ ? trueType :
+                            booleanType;
+                case 43 /* PlusPlusToken */:
+                case 44 /* MinusMinusToken */:
+                    var ok = checkArithmeticOperandType(node.operand, checkNonNullType(operandType, node.operand), ts.Diagnostics.An_arithmetic_operand_must_be_of_type_any_number_or_an_enum_type);
+                    if (ok) {
+                        // run check only if former checks succeeded to avoid reporting cascading errors
+                        checkReferenceExpression(node.operand, ts.Diagnostics.The_operand_of_an_increment_or_decrement_operator_must_be_a_variable_or_a_property_access);
+                    }
+                    return numberType;
+            }
+            return errorType;
+        }
+        function checkPostfixUnaryExpression(node) {
+            var operandType = checkExpression(node.operand);
+            if (operandType === silentNeverType) {
+                return silentNeverType;
+            }
+            var ok = checkArithmeticOperandType(node.operand, checkNonNullType(operandType, node.operand), ts.Diagnostics.An_arithmetic_operand_must_be_of_type_any_number_or_an_enum_type);
+            if (ok) {
+                // run check only if former checks succeeded to avoid reporting cascading errors
+                checkReferenceExpression(node.operand, ts.Diagnostics.The_operand_of_an_increment_or_decrement_operator_must_be_a_variable_or_a_property_access);
+            }
+            return numberType;
+        }
+        // Return true if type might be of the given kind. A union or intersection type might be of a given
+        // kind if at least one constituent type is of the given kind.
+        function maybeTypeOfKind(type, kind) {
+            if (type.flags & kind & ~134217728 /* GenericMappedType */ || kind & 134217728 /* GenericMappedType */ && isGenericMappedType(type)) {
+                return true;
+            }
+            if (type.flags & 786432 /* UnionOrIntersection */) {
+                var types = type.types;
+                for (var _i = 0, types_16 = types; _i < types_16.length; _i++) {
+                    var t = types_16[_i];
+                    if (maybeTypeOfKind(t, kind)) {
+                        return true;
+                    }
+                }
+            }
+            return false;
+        }
+        function isTypeAssignableToKind(source, kind, strict) {
+            if (source.flags & kind) {
+                return true;
+            }
+            if (strict && source.flags & (3 /* AnyOrUnknown */ | 4096 /* Void */ | 8192 /* Undefined */ | 16384 /* Null */)) {
+                return false;
+            }
+            return !!(kind & 168 /* NumberLike */) && isTypeAssignableTo(source, numberType) ||
+                !!(kind & 68 /* StringLike */) && isTypeAssignableTo(source, stringType) ||
+                !!(kind & 272 /* BooleanLike */) && isTypeAssignableTo(source, booleanType) ||
+                !!(kind & 4096 /* Void */) && isTypeAssignableTo(source, voidType) ||
+                !!(kind & 32768 /* Never */) && isTypeAssignableTo(source, neverType) ||
+                !!(kind & 16384 /* Null */) && isTypeAssignableTo(source, nullType) ||
+                !!(kind & 8192 /* Undefined */) && isTypeAssignableTo(source, undefinedType) ||
+                !!(kind & 1024 /* ESSymbol */) && isTypeAssignableTo(source, esSymbolType) ||
+                !!(kind & 16777216 /* NonPrimitive */) && isTypeAssignableTo(source, nonPrimitiveType);
+        }
+        function allTypesAssignableToKind(source, kind, strict) {
+            return source.flags & 262144 /* Union */ ?
+                ts.every(source.types, function (subType) { return allTypesAssignableToKind(subType, kind, strict); }) :
+                isTypeAssignableToKind(source, kind, strict);
+        }
+        function isConstEnumObjectType(type) {
+            return !!(ts.getObjectFlags(type) & 16 /* Anonymous */) && !!type.symbol && isConstEnumSymbol(type.symbol);
+        }
+        function isConstEnumSymbol(symbol) {
+            return (symbol.flags & 128 /* ConstEnum */) !== 0;
+        }
+        function checkInstanceOfExpression(left, right, leftType, rightType) {
+            if (leftType === silentNeverType || rightType === silentNeverType) {
+                return silentNeverType;
+            }
+            // TypeScript 1.0 spec (April 2014): 4.15.4
+            // The instanceof operator requires the left operand to be of type Any, an object type, or a type parameter type,
+            // and the right operand to be of type Any, a subtype of the 'Function' interface type, or have a call or construct signature.
+            // The result is always of the Boolean primitive type.
+            // NOTE: do not raise error if leftType is unknown as related error was already reported
+            if (!isTypeAny(leftType) &&
+                allTypesAssignableToKind(leftType, 32764 /* Primitive */)) {
+                error(left, ts.Diagnostics.The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_parameter);
+            }
+            // NOTE: do not raise error if right is unknown as related error was already reported
+            if (!(isTypeAny(rightType) || typeHasCallOrConstructSignatures(rightType) || isTypeSubtypeOf(rightType, globalFunctionType))) {
+                error(right, ts.Diagnostics.The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_Function_interface_type);
+            }
+            return booleanType;
+        }
+        function checkInExpression(left, right, leftType, rightType) {
+            if (leftType === silentNeverType || rightType === silentNeverType) {
+                return silentNeverType;
+            }
+            leftType = checkNonNullType(leftType, left);
+            rightType = checkNonNullType(rightType, right);
+            // TypeScript 1.0 spec (April 2014): 4.15.5
+            // The in operator requires the left operand to be of type Any, the String primitive type, or the Number primitive type,
+            // and the right operand to be of type Any, an object type, or a type parameter type.
+            // The result is always of the Boolean primitive type.
+            if (!(isTypeComparableTo(leftType, stringType) || isTypeAssignableToKind(leftType, 168 /* NumberLike */ | 3072 /* ESSymbolLike */))) {
+                error(left, ts.Diagnostics.The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol);
+            }
+            if (!isTypeAssignableToKind(rightType, 16777216 /* NonPrimitive */ | 14745600 /* InstantiableNonPrimitive */)) {
+                error(right, ts.Diagnostics.The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter);
+            }
+            return booleanType;
+        }
+        function checkObjectLiteralAssignment(node, sourceType) {
+            var properties = node.properties;
+            if (strictNullChecks && properties.length === 0) {
+                return checkNonNullType(sourceType, node);
+            }
+            for (var _i = 0, properties_7 = properties; _i < properties_7.length; _i++) {
+                var p = properties_7[_i];
+                checkObjectLiteralDestructuringPropertyAssignment(sourceType, p, properties);
+            }
+            return sourceType;
+        }
+        /** Note: If property cannot be a SpreadAssignment, then allProperties does not need to be provided */
+        function checkObjectLiteralDestructuringPropertyAssignment(objectLiteralType, property, allProperties) {
+            if (property.kind === 270 /* PropertyAssignment */ || property.kind === 271 /* ShorthandPropertyAssignment */) {
+                var name = property.name;
+                if (name.kind === 147 /* ComputedPropertyName */) {
+                    checkComputedPropertyName(name);
+                }
+                if (isComputedNonLiteralName(name)) {
+                    return undefined;
+                }
+                var text = ts.getTextOfPropertyName(name);
+                var type = isTypeAny(objectLiteralType)
+                    ? objectLiteralType
+                    : getTypeOfPropertyOfType(objectLiteralType, text) ||
+                        isNumericLiteralName(text) && getIndexTypeOfType(objectLiteralType, 1 /* Number */) ||
+                        getIndexTypeOfType(objectLiteralType, 0 /* String */);
+                if (type) {
+                    if (property.kind === 271 /* ShorthandPropertyAssignment */) {
+                        return checkDestructuringAssignment(property, type);
+                    }
+                    else {
+                        // non-shorthand property assignments should always have initializers
+                        return checkDestructuringAssignment(property.initializer, type);
+                    }
+                }
+                else {
+                    error(name, ts.Diagnostics.Type_0_has_no_property_1_and_no_string_index_signature, typeToString(objectLiteralType), ts.declarationNameToString(name));
+                }
+            }
+            else if (property.kind === 272 /* SpreadAssignment */) {
+                if (languageVersion < 6 /* ESNext */) {
+                    checkExternalEmitHelpers(property, 4 /* Rest */);
+                }
+                var nonRestNames = [];
+                if (allProperties) {
+                    for (var i = 0; i < allProperties.length - 1; i++) {
+                        nonRestNames.push(allProperties[i].name);
+                    }
+                }
+                var type = getRestType(objectLiteralType, nonRestNames, objectLiteralType.symbol);
+                checkGrammarForDisallowedTrailingComma(allProperties, ts.Diagnostics.A_rest_parameter_or_binding_pattern_may_not_have_a_trailing_comma);
+                return checkDestructuringAssignment(property.expression, type);
+            }
+            else {
+                error(property, ts.Diagnostics.Property_assignment_expected);
+            }
+        }
+        function checkArrayLiteralAssignment(node, sourceType, checkMode) {
+            var elements = node.elements;
+            if (languageVersion < 2 /* ES2015 */ && compilerOptions.downlevelIteration) {
+                checkExternalEmitHelpers(node, 512 /* Read */);
+            }
+            // This elementType will be used if the specific property corresponding to this index is not
+            // present (aka the tuple element property). This call also checks that the parentType is in
+            // fact an iterable or array (depending on target language).
+            var elementType = checkIteratedTypeOrElementType(sourceType, node, /*allowStringInput*/ false, /*allowAsyncIterables*/ false) || errorType;
+            for (var i = 0; i < elements.length; i++) {
+                checkArrayLiteralDestructuringElementAssignment(node, sourceType, i, elementType, checkMode);
+            }
+            return sourceType;
+        }
+        function checkArrayLiteralDestructuringElementAssignment(node, sourceType, elementIndex, elementType, checkMode) {
+            var elements = node.elements;
+            var element = elements[elementIndex];
+            if (element.kind !== 206 /* OmittedExpression */) {
+                if (element.kind !== 204 /* SpreadElement */) {
+                    var propName = "" + elementIndex;
+                    var type = isTypeAny(sourceType)
+                        ? sourceType
+                        : isTupleLikeType(sourceType)
+                            ? getTypeOfPropertyOfType(sourceType, propName)
+                            : elementType;
+                    if (type) {
+                        return checkDestructuringAssignment(element, type, checkMode);
+                    }
+                    else {
+                        // We still need to check element expression here because we may need to set appropriate flag on the expression
+                        // such as NodeCheckFlags.LexicalThis on "this"expression.
+                        checkExpression(element);
+                        if (isTupleType(sourceType)) {
+                            error(element, ts.Diagnostics.Tuple_type_0_with_length_1_cannot_be_assigned_to_tuple_with_length_2, typeToString(sourceType), getTypeReferenceArity(sourceType), elements.length);
+                        }
+                        else {
+                            error(element, ts.Diagnostics.Type_0_has_no_property_1, typeToString(sourceType), propName);
+                        }
+                    }
+                }
+                else {
+                    if (elementIndex < elements.length - 1) {
+                        error(element, ts.Diagnostics.A_rest_element_must_be_last_in_a_destructuring_pattern);
+                    }
+                    else {
+                        var restExpression = element.expression;
+                        if (restExpression.kind === 200 /* BinaryExpression */ && restExpression.operatorToken.kind === 58 /* EqualsToken */) {
+                            error(restExpression.operatorToken, ts.Diagnostics.A_rest_element_cannot_have_an_initializer);
+                        }
+                        else {
+                            checkGrammarForDisallowedTrailingComma(node.elements, ts.Diagnostics.A_rest_parameter_or_binding_pattern_may_not_have_a_trailing_comma);
+                            return checkDestructuringAssignment(restExpression, createArrayType(elementType), checkMode);
+                        }
+                    }
+                }
+            }
+            return undefined;
+        }
+        function checkDestructuringAssignment(exprOrAssignment, sourceType, checkMode) {
+            var target;
+            if (exprOrAssignment.kind === 271 /* ShorthandPropertyAssignment */) {
+                var prop = exprOrAssignment;
+                if (prop.objectAssignmentInitializer) {
+                    // In strict null checking mode, if a default value of a non-undefined type is specified, remove
+                    // undefined from the final type.
+                    if (strictNullChecks &&
+                        !(getFalsyFlags(checkExpression(prop.objectAssignmentInitializer)) & 8192 /* Undefined */)) {
+                        sourceType = getTypeWithFacts(sourceType, 131072 /* NEUndefined */);
+                    }
+                    checkBinaryLikeExpression(prop.name, prop.equalsToken, prop.objectAssignmentInitializer, checkMode);
+                }
+                target = exprOrAssignment.name;
+            }
+            else {
+                target = exprOrAssignment;
+            }
+            if (target.kind === 200 /* BinaryExpression */ && target.operatorToken.kind === 58 /* EqualsToken */) {
+                checkBinaryExpression(target, checkMode);
+                target = target.left;
+            }
+            if (target.kind === 184 /* ObjectLiteralExpression */) {
+                return checkObjectLiteralAssignment(target, sourceType);
+            }
+            if (target.kind === 183 /* ArrayLiteralExpression */) {
+                return checkArrayLiteralAssignment(target, sourceType, checkMode);
+            }
+            return checkReferenceAssignment(target, sourceType, checkMode);
+        }
+        function checkReferenceAssignment(target, sourceType, checkMode) {
+            var targetType = checkExpression(target, checkMode);
+            var error = target.parent.kind === 272 /* SpreadAssignment */ ?
+                ts.Diagnostics.The_target_of_an_object_rest_assignment_must_be_a_variable_or_a_property_access :
+                ts.Diagnostics.The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access;
+            if (checkReferenceExpression(target, error)) {
+                checkTypeAssignableTo(sourceType, targetType, target, /*headMessage*/ undefined);
+            }
+            return sourceType;
+        }
+        /**
+         * This is a *shallow* check: An expression is side-effect-free if the
+         * evaluation of the expression *itself* cannot produce side effects.
+         * For example, x++ / 3 is side-effect free because the / operator
+         * does not have side effects.
+         * The intent is to "smell test" an expression for correctness in positions where
+         * its value is discarded (e.g. the left side of the comma operator).
+         */
+        function isSideEffectFree(node) {
+            node = ts.skipParentheses(node);
+            switch (node.kind) {
+                case 71 /* Identifier */:
+                case 9 /* StringLiteral */:
+                case 12 /* RegularExpressionLiteral */:
+                case 189 /* TaggedTemplateExpression */:
+                case 202 /* TemplateExpression */:
+                case 13 /* NoSubstitutionTemplateLiteral */:
+                case 8 /* NumericLiteral */:
+                case 101 /* TrueKeyword */:
+                case 86 /* FalseKeyword */:
+                case 95 /* NullKeyword */:
+                case 140 /* UndefinedKeyword */:
+                case 192 /* FunctionExpression */:
+                case 205 /* ClassExpression */:
+                case 193 /* ArrowFunction */:
+                case 183 /* ArrayLiteralExpression */:
+                case 184 /* ObjectLiteralExpression */:
+                case 195 /* TypeOfExpression */:
+                case 209 /* NonNullExpression */:
+                case 256 /* JsxSelfClosingElement */:
+                case 255 /* JsxElement */:
+                    return true;
+                case 201 /* ConditionalExpression */:
+                    return isSideEffectFree(node.whenTrue) &&
+                        isSideEffectFree(node.whenFalse);
+                case 200 /* BinaryExpression */:
+                    if (ts.isAssignmentOperator(node.operatorToken.kind)) {
+                        return false;
+                    }
+                    return isSideEffectFree(node.left) &&
+                        isSideEffectFree(node.right);
+                case 198 /* PrefixUnaryExpression */:
+                case 199 /* PostfixUnaryExpression */:
+                    // Unary operators ~, !, +, and - have no side effects.
+                    // The rest do.
+                    switch (node.operator) {
+                        case 51 /* ExclamationToken */:
+                        case 37 /* PlusToken */:
+                        case 38 /* MinusToken */:
+                        case 52 /* TildeToken */:
+                            return true;
+                    }
+                    return false;
+                // Some forms listed here for clarity
+                case 196 /* VoidExpression */: // Explicit opt-out
+                case 190 /* TypeAssertionExpression */: // Not SEF, but can produce useful type warnings
+                case 208 /* AsExpression */: // Not SEF, but can produce useful type warnings
+                default:
+                    return false;
+            }
+        }
+        function isTypeEqualityComparableTo(source, target) {
+            return (target.flags & 24576 /* Nullable */) !== 0 || isTypeComparableTo(source, target);
+        }
+        function checkBinaryExpression(node, checkMode) {
+            if (ts.isInJavaScriptFile(node) && ts.getAssignedJavascriptInitializer(node)) {
+                return checkExpression(node.right, checkMode);
+            }
+            return checkBinaryLikeExpression(node.left, node.operatorToken, node.right, checkMode, node);
+        }
+        function checkBinaryLikeExpression(left, operatorToken, right, checkMode, errorNode) {
+            var operator = operatorToken.kind;
+            if (operator === 58 /* EqualsToken */ && (left.kind === 184 /* ObjectLiteralExpression */ || left.kind === 183 /* ArrayLiteralExpression */)) {
+                return checkDestructuringAssignment(left, checkExpression(right, checkMode), checkMode);
+            }
+            var leftType = checkExpression(left, checkMode);
+            var rightType = checkExpression(right, checkMode);
+            switch (operator) {
+                case 39 /* AsteriskToken */:
+                case 40 /* AsteriskAsteriskToken */:
+                case 61 /* AsteriskEqualsToken */:
+                case 62 /* AsteriskAsteriskEqualsToken */:
+                case 41 /* SlashToken */:
+                case 63 /* SlashEqualsToken */:
+                case 42 /* PercentToken */:
+                case 64 /* PercentEqualsToken */:
+                case 38 /* MinusToken */:
+                case 60 /* MinusEqualsToken */:
+                case 45 /* LessThanLessThanToken */:
+                case 65 /* LessThanLessThanEqualsToken */:
+                case 46 /* GreaterThanGreaterThanToken */:
+                case 66 /* GreaterThanGreaterThanEqualsToken */:
+                case 47 /* GreaterThanGreaterThanGreaterThanToken */:
+                case 67 /* GreaterThanGreaterThanGreaterThanEqualsToken */:
+                case 49 /* BarToken */:
+                case 69 /* BarEqualsToken */:
+                case 50 /* CaretToken */:
+                case 70 /* CaretEqualsToken */:
+                case 48 /* AmpersandToken */:
+                case 68 /* AmpersandEqualsToken */:
+                    if (leftType === silentNeverType || rightType === silentNeverType) {
+                        return silentNeverType;
+                    }
+                    leftType = checkNonNullType(leftType, left);
+                    rightType = checkNonNullType(rightType, right);
+                    var suggestedOperator = void 0;
+                    // if a user tries to apply a bitwise operator to 2 boolean operands
+                    // try and return them a helpful suggestion
+                    if ((leftType.flags & 272 /* BooleanLike */) &&
+                        (rightType.flags & 272 /* BooleanLike */) &&
+                        (suggestedOperator = getSuggestedBooleanOperator(operatorToken.kind)) !== undefined) {
+                        error(errorNode || operatorToken, ts.Diagnostics.The_0_operator_is_not_allowed_for_boolean_types_Consider_using_1_instead, ts.tokenToString(operatorToken.kind), ts.tokenToString(suggestedOperator));
+                    }
+                    else {
+                        // otherwise just check each operand separately and report errors as normal
+                        var leftOk = checkArithmeticOperandType(left, leftType, ts.Diagnostics.The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_or_an_enum_type);
+                        var rightOk = checkArithmeticOperandType(right, rightType, ts.Diagnostics.The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_or_an_enum_type);
+                        if (leftOk && rightOk) {
+                            checkAssignmentOperator(numberType);
+                        }
+                    }
+                    return numberType;
+                case 37 /* PlusToken */:
+                case 59 /* PlusEqualsToken */:
+                    if (leftType === silentNeverType || rightType === silentNeverType) {
+                        return silentNeverType;
+                    }
+                    if (!isTypeAssignableToKind(leftType, 68 /* StringLike */) && !isTypeAssignableToKind(rightType, 68 /* StringLike */)) {
+                        leftType = checkNonNullType(leftType, left);
+                        rightType = checkNonNullType(rightType, right);
+                    }
+                    var resultType = void 0;
+                    if (isTypeAssignableToKind(leftType, 168 /* NumberLike */, /*strict*/ true) && isTypeAssignableToKind(rightType, 168 /* NumberLike */, /*strict*/ true)) {
+                        // Operands of an enum type are treated as having the primitive type Number.
+                        // If both operands are of the Number primitive type, the result is of the Number primitive type.
+                        resultType = numberType;
+                    }
+                    else if (isTypeAssignableToKind(leftType, 68 /* StringLike */, /*strict*/ true) || isTypeAssignableToKind(rightType, 68 /* StringLike */, /*strict*/ true)) {
+                        // If one or both operands are of the String primitive type, the result is of the String primitive type.
+                        resultType = stringType;
+                    }
+                    else if (isTypeAny(leftType) || isTypeAny(rightType)) {
+                        // Otherwise, the result is of type Any.
+                        // NOTE: unknown type here denotes error type. Old compiler treated this case as any type so do we.
+                        resultType = leftType === errorType || rightType === errorType ? errorType : anyType;
+                    }
+                    // Symbols are not allowed at all in arithmetic expressions
+                    if (resultType && !checkForDisallowedESSymbolOperand(operator)) {
+                        return resultType;
+                    }
+                    if (!resultType) {
+                        reportOperatorError();
+                        return anyType;
+                    }
+                    if (operator === 59 /* PlusEqualsToken */) {
+                        checkAssignmentOperator(resultType);
+                    }
+                    return resultType;
+                case 27 /* LessThanToken */:
+                case 29 /* GreaterThanToken */:
+                case 30 /* LessThanEqualsToken */:
+                case 31 /* GreaterThanEqualsToken */:
+                    if (checkForDisallowedESSymbolOperand(operator)) {
+                        leftType = getBaseTypeOfLiteralType(checkNonNullType(leftType, left));
+                        rightType = getBaseTypeOfLiteralType(checkNonNullType(rightType, right));
+                        if (!isTypeComparableTo(leftType, rightType) && !isTypeComparableTo(rightType, leftType)) {
+                            reportOperatorError();
+                        }
+                    }
+                    return booleanType;
+                case 32 /* EqualsEqualsToken */:
+                case 33 /* ExclamationEqualsToken */:
+                case 34 /* EqualsEqualsEqualsToken */:
+                case 35 /* ExclamationEqualsEqualsToken */:
+                    var leftIsLiteral = isLiteralType(leftType);
+                    var rightIsLiteral = isLiteralType(rightType);
+                    if (!leftIsLiteral || !rightIsLiteral) {
+                        leftType = leftIsLiteral ? getBaseTypeOfLiteralType(leftType) : leftType;
+                        rightType = rightIsLiteral ? getBaseTypeOfLiteralType(rightType) : rightType;
+                    }
+                    if (!isTypeEqualityComparableTo(leftType, rightType) && !isTypeEqualityComparableTo(rightType, leftType)) {
+                        reportOperatorError();
+                    }
+                    return booleanType;
+                case 93 /* InstanceOfKeyword */:
+                    return checkInstanceOfExpression(left, right, leftType, rightType);
+                case 92 /* InKeyword */:
+                    return checkInExpression(left, right, leftType, rightType);
+                case 53 /* AmpersandAmpersandToken */:
+                    return getTypeFacts(leftType) & 1048576 /* Truthy */ ?
+                        getUnionType([extractDefinitelyFalsyTypes(strictNullChecks ? leftType : getBaseTypeOfLiteralType(rightType)), rightType]) :
+                        leftType;
+                case 54 /* BarBarToken */:
+                    return getTypeFacts(leftType) & 2097152 /* Falsy */ ?
+                        getUnionType([removeDefinitelyFalsyTypes(leftType), rightType], 2 /* Subtype */) :
+                        leftType;
+                case 58 /* EqualsToken */:
+                    checkSpecialAssignment(left, right);
+                    checkAssignmentOperator(rightType);
+                    return getRegularTypeOfObjectLiteral(rightType);
+                case 26 /* CommaToken */:
+                    if (!compilerOptions.allowUnreachableCode && isSideEffectFree(left) && !isEvalNode(right)) {
+                        error(left, ts.Diagnostics.Left_side_of_comma_operator_is_unused_and_has_no_side_effects);
+                    }
+                    return rightType;
+                default:
+                    return ts.Debug.fail();
+            }
+            function checkSpecialAssignment(left, right) {
+                var special = ts.getSpecialPropertyAssignmentKind(left.parent);
+                if (special === 2 /* ModuleExports */) {
+                    var rightType_1 = checkExpression(right, checkMode);
+                    for (var _i = 0, _a = getPropertiesOfObjectType(rightType_1); _i < _a.length; _i++) {
+                        var prop = _a[_i];
+                        var propType = getTypeOfSymbol(prop);
+                        if (propType.symbol && propType.symbol.flags & 32 /* Class */) {
+                            var name = prop.escapedName;
+                            var symbol = resolveName(prop.valueDeclaration, name, 67901928 /* Type */, undefined, name, /*isUse*/ false);
+                            if (symbol && symbol.declarations.some(ts.isJSDocTypedefTag)) {
+                                grammarErrorOnNode(symbol.declarations[0], ts.Diagnostics.Duplicate_identifier_0, ts.unescapeLeadingUnderscores(name));
+                                return grammarErrorOnNode(prop.valueDeclaration, ts.Diagnostics.Duplicate_identifier_0, ts.unescapeLeadingUnderscores(name));
+                            }
+                        }
+                    }
+                }
+            }
+            function isEvalNode(node) {
+                return node.kind === 71 /* Identifier */ && node.escapedText === "eval";
+            }
+            // Return true if there was no error, false if there was an error.
+            function checkForDisallowedESSymbolOperand(operator) {
+                var offendingSymbolOperand = maybeTypeOfKind(leftType, 3072 /* ESSymbolLike */) ? left :
+                    maybeTypeOfKind(rightType, 3072 /* ESSymbolLike */) ? right :
+                        undefined;
+                if (offendingSymbolOperand) {
+                    error(offendingSymbolOperand, ts.Diagnostics.The_0_operator_cannot_be_applied_to_type_symbol, ts.tokenToString(operator));
+                    return false;
+                }
+                return true;
+            }
+            function getSuggestedBooleanOperator(operator) {
+                switch (operator) {
+                    case 49 /* BarToken */:
+                    case 69 /* BarEqualsToken */:
+                        return 54 /* BarBarToken */;
+                    case 50 /* CaretToken */:
+                    case 70 /* CaretEqualsToken */:
+                        return 35 /* ExclamationEqualsEqualsToken */;
+                    case 48 /* AmpersandToken */:
+                    case 68 /* AmpersandEqualsToken */:
+                        return 53 /* AmpersandAmpersandToken */;
+                    default:
+                        return undefined;
+                }
+            }
+            function checkAssignmentOperator(valueType) {
+                if (produceDiagnostics && ts.isAssignmentOperator(operator)) {
+                    // TypeScript 1.0 spec (April 2014): 4.17
+                    // An assignment of the form
+                    //    VarExpr = ValueExpr
+                    // requires VarExpr to be classified as a reference
+                    // A compound assignment furthermore requires VarExpr to be classified as a reference (section 4.1)
+                    // and the type of the non-compound operation to be assignable to the type of VarExpr.
+                    if (checkReferenceExpression(left, ts.Diagnostics.The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access)
+                        && (!ts.isIdentifier(left) || ts.unescapeLeadingUnderscores(left.escapedText) !== "exports")) {
+                        // to avoid cascading errors check assignability only if 'isReference' check succeeded and no errors were reported
+                        checkTypeAssignableTo(valueType, leftType, left, /*headMessage*/ undefined);
+                    }
+                }
+            }
+            function reportOperatorError() {
+                error(errorNode || operatorToken, ts.Diagnostics.Operator_0_cannot_be_applied_to_types_1_and_2, ts.tokenToString(operatorToken.kind), typeToString(leftType), typeToString(rightType));
+            }
+        }
+        function isYieldExpressionInClass(node) {
+            var current = node;
+            var parent = node.parent;
+            while (parent) {
+                if (ts.isFunctionLike(parent) && current === parent.body) {
+                    return false;
+                }
+                else if (ts.isClassLike(current)) {
+                    return true;
+                }
+                current = parent;
+                parent = parent.parent;
+            }
+            return false;
+        }
+        function checkYieldExpression(node) {
+            // Grammar checking
+            if (produceDiagnostics) {
+                if (!(node.flags & 4096 /* YieldContext */) || isYieldExpressionInClass(node)) {
+                    grammarErrorOnFirstToken(node, ts.Diagnostics.A_yield_expression_is_only_allowed_in_a_generator_body);
+                }
+                if (isInParameterInitializerBeforeContainingFunction(node)) {
+                    error(node, ts.Diagnostics.yield_expressions_cannot_be_used_in_a_parameter_initializer);
+                }
+            }
+            var func = ts.getContainingFunction(node);
+            if (!func)
+                return anyType;
+            var functionFlags = ts.getFunctionFlags(func);
+            if (!(functionFlags & 1 /* Generator */)) {
+                // If the user's code is syntactically correct, the func should always have a star. After all, we are in a yield context.
+                return anyType;
+            }
+            if (node.asteriskToken) {
+                // Async generator functions prior to ESNext require the __await, __asyncDelegator,
+                // and __asyncValues helpers
+                if ((functionFlags & 3 /* AsyncGenerator */) === 3 /* AsyncGenerator */ &&
+                    languageVersion < 6 /* ESNext */) {
+                    checkExternalEmitHelpers(node, 26624 /* AsyncDelegatorIncludes */);
+                }
+                // Generator functions prior to ES2015 require the __values helper
+                if ((functionFlags & 3 /* AsyncGenerator */) === 1 /* Generator */ &&
+                    languageVersion < 2 /* ES2015 */ && compilerOptions.downlevelIteration) {
+                    checkExternalEmitHelpers(node, 256 /* Values */);
+                }
+            }
+            var isAsync = (functionFlags & 2 /* Async */) !== 0;
+            var yieldedType = getYieldedTypeOfYieldExpression(node, isAsync); // TODO: GH#18217
+            // There is no point in doing an assignability check if the function
+            // has no explicit return type because the return type is directly computed
+            // from the yield expressions.
+            var returnType = ts.getEffectiveReturnTypeNode(func);
+            if (returnType) {
+                var signatureElementType = getIteratedTypeOfGenerator(getTypeFromTypeNode(returnType), isAsync) || anyType;
+                checkTypeAssignableTo(yieldedType, signatureElementType, node.expression || node, /*headMessage*/ undefined);
+            }
+            // Both yield and yield* expressions have type 'any'
+            return anyType;
+        }
+        function checkConditionalExpression(node, checkMode) {
+            checkExpression(node.condition);
+            var type1 = checkExpression(node.whenTrue, checkMode);
+            var type2 = checkExpression(node.whenFalse, checkMode);
+            return getUnionType([type1, type2], 2 /* Subtype */);
+        }
+        function checkTemplateExpression(node) {
+            // We just want to check each expressions, but we are unconcerned with
+            // the type of each expression, as any value may be coerced into a string.
+            // It is worth asking whether this is what we really want though.
+            // A place where we actually *are* concerned with the expressions' types are
+            // in tagged templates.
+            ts.forEach(node.templateSpans, function (templateSpan) {
+                if (maybeTypeOfKind(checkExpression(templateSpan.expression), 3072 /* ESSymbolLike */)) {
+                    error(templateSpan.expression, ts.Diagnostics.Type_0_cannot_be_converted_to_type_1, typeToString(esSymbolType), typeToString(stringType));
+                }
+            });
+            return stringType;
+        }
+        function getContextNode(node) {
+            if (node.kind === 263 /* JsxAttributes */) {
+                return node.parent.parent; // Needs to be the root JsxElement, so it encompasses the attributes _and_ the children (which are essentially part of the attributes)
+            }
+            return node;
+        }
+        function checkExpressionWithContextualType(node, contextualType, contextualMapper) {
+            var context = getContextNode(node);
+            var saveContextualType = context.contextualType;
+            var saveContextualMapper = context.contextualMapper;
+            context.contextualType = contextualType;
+            context.contextualMapper = contextualMapper;
+            var checkMode = contextualMapper === identityMapper ? 1 /* SkipContextSensitive */ :
+                contextualMapper ? 2 /* Inferential */ : 3 /* Contextual */;
+            var result = checkExpression(node, checkMode);
+            context.contextualType = saveContextualType;
+            context.contextualMapper = saveContextualMapper;
+            return result;
+        }
+        function checkExpressionCached(node, checkMode) {
+            var links = getNodeLinks(node);
+            if (!links.resolvedType) {
+                if (checkMode) {
+                    return checkExpression(node, checkMode);
+                }
+                // When computing a type that we're going to cache, we need to ignore any ongoing control flow
+                // analysis because variables may have transient types in indeterminable states. Moving flowLoopStart
+                // to the top of the stack ensures all transient types are computed from a known point.
+                var saveFlowLoopStart = flowLoopStart;
+                flowLoopStart = flowLoopCount;
+                links.resolvedType = checkExpression(node, checkMode);
+                flowLoopStart = saveFlowLoopStart;
+            }
+            return links.resolvedType;
+        }
+        function isTypeAssertion(node) {
+            node = ts.skipParentheses(node);
+            return node.kind === 190 /* TypeAssertionExpression */ || node.kind === 208 /* AsExpression */;
+        }
+        function checkDeclarationInitializer(declaration) {
+            var initializer = ts.getEffectiveInitializer(declaration);
+            var type = getTypeOfExpression(initializer, /*cache*/ true);
+            var widened = ts.getCombinedNodeFlags(declaration) & 2 /* Const */ ||
+                (ts.getCombinedModifierFlags(declaration) & 64 /* Readonly */ && !ts.isParameterPropertyDeclaration(declaration)) ||
+                isTypeAssertion(initializer) ? type : getWidenedLiteralType(type);
+            if (ts.isInJavaScriptFile(declaration)) {
+                if (widened.flags & 24576 /* Nullable */) {
+                    if (noImplicitAny) {
+                        reportImplicitAnyError(declaration, anyType);
+                    }
+                    return anyType;
+                }
+                else if (isEmptyArrayLiteralType(widened)) {
+                    if (noImplicitAny) {
+                        reportImplicitAnyError(declaration, anyArrayType);
+                    }
+                    return anyArrayType;
+                }
+            }
+            return widened;
+        }
+        function isLiteralOfContextualType(candidateType, contextualType) {
+            if (contextualType) {
+                if (contextualType.flags & 786432 /* UnionOrIntersection */) {
+                    var types = contextualType.types;
+                    return ts.some(types, function (t) { return isLiteralOfContextualType(candidateType, t); });
+                }
+                if (contextualType.flags & 14745600 /* InstantiableNonPrimitive */) {
+                    // If the contextual type is a type variable constrained to a primitive type, consider
+                    // this a literal context for literals of that primitive type. For example, given a
+                    // type parameter 'T extends string', infer string literal types for T.
+                    var constraint = getBaseConstraintOfType(contextualType) || emptyObjectType;
+                    return maybeTypeOfKind(constraint, 4 /* String */) && maybeTypeOfKind(candidateType, 64 /* StringLiteral */) ||
+                        maybeTypeOfKind(constraint, 8 /* Number */) && maybeTypeOfKind(candidateType, 128 /* NumberLiteral */) ||
+                        maybeTypeOfKind(constraint, 1024 /* ESSymbol */) && maybeTypeOfKind(candidateType, 2048 /* UniqueESSymbol */) ||
+                        isLiteralOfContextualType(candidateType, constraint);
+                }
+                // If the contextual type is a literal of a particular primitive type, we consider this a
+                // literal context for all literals of that primitive type.
+                return !!(contextualType.flags & (64 /* StringLiteral */ | 1048576 /* Index */) && maybeTypeOfKind(candidateType, 64 /* StringLiteral */) ||
+                    contextualType.flags & 128 /* NumberLiteral */ && maybeTypeOfKind(candidateType, 128 /* NumberLiteral */) ||
+                    contextualType.flags & 256 /* BooleanLiteral */ && maybeTypeOfKind(candidateType, 256 /* BooleanLiteral */) ||
+                    contextualType.flags & 2048 /* UniqueESSymbol */ && maybeTypeOfKind(candidateType, 2048 /* UniqueESSymbol */));
+            }
+            return false;
+        }
+        function checkExpressionForMutableLocation(node, checkMode, contextualType) {
+            if (arguments.length === 2) {
+                contextualType = getContextualType(node);
+            }
+            var type = checkExpression(node, checkMode);
+            return isTypeAssertion(node) ? type :
+                getWidenedLiteralLikeTypeForContextualType(type, contextualType);
+        }
+        function checkPropertyAssignment(node, checkMode) {
+            // Do not use hasDynamicName here, because that returns false for well known symbols.
+            // We want to perform checkComputedPropertyName for all computed properties, including
+            // well known symbols.
+            if (node.name.kind === 147 /* ComputedPropertyName */) {
+                checkComputedPropertyName(node.name);
+            }
+            return checkExpressionForMutableLocation(node.initializer, checkMode);
+        }
+        function checkObjectLiteralMethod(node, checkMode) {
+            // Grammar checking
+            checkGrammarMethod(node);
+            // Do not use hasDynamicName here, because that returns false for well known symbols.
+            // We want to perform checkComputedPropertyName for all computed properties, including
+            // well known symbols.
+            if (node.name.kind === 147 /* ComputedPropertyName */) {
+                checkComputedPropertyName(node.name);
+            }
+            var uninstantiatedType = checkFunctionExpressionOrObjectLiteralMethod(node, checkMode);
+            return instantiateTypeWithSingleGenericCallSignature(node, uninstantiatedType, checkMode);
+        }
+        function instantiateTypeWithSingleGenericCallSignature(node, type, checkMode) {
+            if (checkMode === 2 /* Inferential */) {
+                var signature = getSingleCallSignature(type);
+                if (signature && signature.typeParameters) {
+                    var contextualType = getApparentTypeOfContextualType(node);
+                    if (contextualType) {
+                        var contextualSignature = getSingleCallSignature(getNonNullableType(contextualType));
+                        if (contextualSignature && !contextualSignature.typeParameters) {
+                            return getOrCreateTypeFromSignature(instantiateSignatureInContextOf(signature, contextualSignature, getContextualMapper(node)));
+                        }
+                    }
+                }
+            }
+            return type;
+        }
+        /**
+         * Returns the type of an expression. Unlike checkExpression, this function is simply concerned
+         * with computing the type and may not fully check all contained sub-expressions for errors.
+         * A cache argument of true indicates that if the function performs a full type check, it is ok
+         * to cache the result.
+         */
+        function getTypeOfExpression(node, cache) {
+            // Optimize for the common case of a call to a function with a single non-generic call
+            // signature where we can just fetch the return type without checking the arguments.
+            if (node.kind === 187 /* CallExpression */ && node.expression.kind !== 97 /* SuperKeyword */ && !ts.isRequireCall(node, /*checkArgumentIsStringLiteralLike*/ true) && !isSymbolOrSymbolForCall(node)) {
+                var funcType = checkNonNullExpression(node.expression);
+                var signature = getSingleCallSignature(funcType);
+                if (signature && !signature.typeParameters) {
+                    return getReturnTypeOfSignature(signature);
+                }
+            }
+            // Otherwise simply call checkExpression. Ideally, the entire family of checkXXX functions
+            // should have a parameter that indicates whether full error checking is required such that
+            // we can perform the optimizations locally.
+            return cache ? checkExpressionCached(node) : checkExpression(node);
+        }
+        /**
+         * Returns the type of an expression. Unlike checkExpression, this function is simply concerned
+         * with computing the type and may not fully check all contained sub-expressions for errors.
+         * It is intended for uses where you know there is no contextual type,
+         * and requesting the contextual type might cause a circularity or other bad behaviour.
+         * It sets the contextual type of the node to any before calling getTypeOfExpression.
+         */
+        function getContextFreeTypeOfExpression(node) {
+            var saveContextualType = node.contextualType;
+            node.contextualType = anyType;
+            var type = getTypeOfExpression(node);
+            node.contextualType = saveContextualType;
+            return type;
+        }
+        function checkExpresionNoReturn(node) {
+            checkExpression(node);
+        }
+        // Checks an expression and returns its type. The contextualMapper parameter serves two purposes: When
+        // contextualMapper is not undefined and not equal to the identityMapper function object it indicates that the
+        // expression is being inferentially typed (section 4.15.2 in spec) and provides the type mapper to use in
+        // conjunction with the generic contextual type. When contextualMapper is equal to the identityMapper function
+        // object, it serves as an indicator that all contained function and arrow expressions should be considered to
+        // have the wildcard function type; this form of type check is used during overload resolution to exclude
+        // contextually typed function and arrow expressions in the initial phase.
+        function checkExpression(node, checkMode) {
+            var type;
+            if (node.kind === 146 /* QualifiedName */) {
+                type = checkQualifiedName(node);
+            }
+            else {
+                var uninstantiatedType = checkExpressionWorker(node, checkMode);
+                type = instantiateTypeWithSingleGenericCallSignature(node, uninstantiatedType, checkMode);
+            }
+            if (isConstEnumObjectType(type)) {
+                // enum object type for const enums are only permitted in:
+                // - 'left' in property access
+                // - 'object' in indexed access
+                // - target in rhs of import statement
+                var ok = (node.parent.kind === 185 /* PropertyAccessExpression */ && node.parent.expression === node) ||
+                    (node.parent.kind === 186 /* ElementAccessExpression */ && node.parent.expression === node) ||
+                    ((node.kind === 71 /* Identifier */ || node.kind === 146 /* QualifiedName */) && isInRightSideOfImportOrExportAssignment(node) ||
+                        (node.parent.kind === 165 /* TypeQuery */ && node.parent.exprName === node));
+                if (!ok) {
+                    error(node, ts.Diagnostics.const_enums_can_only_be_used_in_property_or_index_access_expressions_or_the_right_hand_side_of_an_import_declaration_or_export_assignment_or_type_query);
+                }
+            }
+            return type;
+        }
+        function checkParenthesizedExpression(node, checkMode) {
+            var tag = ts.isInJavaScriptFile(node) ? ts.getJSDocTypeTag(node) : undefined;
+            if (tag) {
+                return checkAssertionWorker(tag, tag.typeExpression.type, node.expression, checkMode);
+            }
+            return checkExpression(node.expression, checkMode);
+        }
+        function checkExpressionWorker(node, checkMode) {
+            switch (node.kind) {
+                case 71 /* Identifier */:
+                    return checkIdentifier(node);
+                case 99 /* ThisKeyword */:
+                    return checkThisExpression(node);
+                case 97 /* SuperKeyword */:
+                    return checkSuperExpression(node);
+                case 95 /* NullKeyword */:
+                    return nullWideningType;
+                case 13 /* NoSubstitutionTemplateLiteral */:
+                case 9 /* StringLiteral */:
+                    return getFreshTypeOfLiteralType(getLiteralType(node.text));
+                case 8 /* NumericLiteral */:
+                    checkGrammarNumericLiteral(node);
+                    return getFreshTypeOfLiteralType(getLiteralType(+node.text));
+                case 101 /* TrueKeyword */:
+                    return trueType;
+                case 86 /* FalseKeyword */:
+                    return falseType;
+                case 202 /* TemplateExpression */:
+                    return checkTemplateExpression(node);
+                case 12 /* RegularExpressionLiteral */:
+                    return globalRegExpType;
+                case 183 /* ArrayLiteralExpression */:
+                    return checkArrayLiteral(node, checkMode);
+                case 184 /* ObjectLiteralExpression */:
+                    return checkObjectLiteral(node, checkMode);
+                case 185 /* PropertyAccessExpression */:
+                    return checkPropertyAccessExpression(node);
+                case 186 /* ElementAccessExpression */:
+                    return checkIndexedAccess(node);
+                case 187 /* CallExpression */:
+                    if (node.expression.kind === 91 /* ImportKeyword */) {
+                        return checkImportCallExpression(node);
+                    }
+                /* falls through */
+                case 188 /* NewExpression */:
+                    return checkCallExpression(node);
+                case 189 /* TaggedTemplateExpression */:
+                    return checkTaggedTemplateExpression(node);
+                case 191 /* ParenthesizedExpression */:
+                    return checkParenthesizedExpression(node, checkMode);
+                case 205 /* ClassExpression */:
+                    return checkClassExpression(node);
+                case 192 /* FunctionExpression */:
+                case 193 /* ArrowFunction */:
+                    return checkFunctionExpressionOrObjectLiteralMethod(node, checkMode);
+                case 195 /* TypeOfExpression */:
+                    return checkTypeOfExpression(node);
+                case 190 /* TypeAssertionExpression */:
+                case 208 /* AsExpression */:
+                    return checkAssertion(node);
+                case 209 /* NonNullExpression */:
+                    return checkNonNullAssertion(node);
+                case 210 /* MetaProperty */:
+                    return checkMetaProperty(node);
+                case 194 /* DeleteExpression */:
+                    return checkDeleteExpression(node);
+                case 196 /* VoidExpression */:
+                    return checkVoidExpression(node);
+                case 197 /* AwaitExpression */:
+                    return checkAwaitExpression(node);
+                case 198 /* PrefixUnaryExpression */:
+                    return checkPrefixUnaryExpression(node);
+                case 199 /* PostfixUnaryExpression */:
+                    return checkPostfixUnaryExpression(node);
+                case 200 /* BinaryExpression */:
+                    return checkBinaryExpression(node, checkMode);
+                case 201 /* ConditionalExpression */:
+                    return checkConditionalExpression(node, checkMode);
+                case 204 /* SpreadElement */:
+                    return checkSpreadExpression(node, checkMode);
+                case 206 /* OmittedExpression */:
+                    return undefinedWideningType;
+                case 203 /* YieldExpression */:
+                    return checkYieldExpression(node);
+                case 265 /* JsxExpression */:
+                    return checkJsxExpression(node, checkMode);
+                case 255 /* JsxElement */:
+                    return checkJsxElement(node, checkMode);
+                case 256 /* JsxSelfClosingElement */:
+                    return checkJsxSelfClosingElement(node, checkMode);
+                case 259 /* JsxFragment */:
+                    return checkJsxFragment(node, checkMode);
+                case 263 /* JsxAttributes */:
+                    return checkJsxAttributes(node, checkMode);
+                case 257 /* JsxOpeningElement */:
+                    ts.Debug.fail("Shouldn't ever directly check a JsxOpeningElement");
+            }
+            return errorType;
+        }
+        // DECLARATION AND STATEMENT TYPE CHECKING
+        function checkTypeParameter(node) {
+            // Grammar Checking
+            if (node.expression) {
+                grammarErrorOnFirstToken(node.expression, ts.Diagnostics.Type_expected);
+            }
+            checkSourceElement(node.constraint);
+            checkSourceElement(node.default);
+            var typeParameter = getDeclaredTypeOfTypeParameter(getSymbolOfNode(node));
+            if (!hasNonCircularBaseConstraint(typeParameter)) {
+                error(node.constraint, ts.Diagnostics.Type_parameter_0_has_a_circular_constraint, typeToString(typeParameter));
+            }
+            if (!hasNonCircularTypeParameterDefault(typeParameter)) {
+                error(node.default, ts.Diagnostics.Type_parameter_0_has_a_circular_default, typeToString(typeParameter));
+            }
+            var constraintType = getConstraintOfTypeParameter(typeParameter);
+            var defaultType = getDefaultFromTypeParameter(typeParameter);
+            if (constraintType && defaultType) {
+                checkTypeAssignableTo(defaultType, getTypeWithThisArgument(constraintType, defaultType), node.default, ts.Diagnostics.Type_0_does_not_satisfy_the_constraint_1);
+            }
+            if (produceDiagnostics) {
+                checkTypeNameIsReserved(node.name, ts.Diagnostics.Type_parameter_name_cannot_be_0);
+            }
+        }
+        function checkParameter(node) {
+            // Grammar checking
+            // It is a SyntaxError if the Identifier "eval" or the Identifier "arguments" occurs as the
+            // Identifier in a PropertySetParameterList of a PropertyAssignment that is contained in strict code
+            // or if its FunctionBody is strict code(11.1.5).
+            checkGrammarDecoratorsAndModifiers(node);
+            checkVariableLikeDeclaration(node);
+            var func = ts.getContainingFunction(node);
+            if (ts.hasModifier(node, 92 /* ParameterPropertyModifier */)) {
+                if (!(func.kind === 155 /* Constructor */ && ts.nodeIsPresent(func.body))) {
+                    error(node, ts.Diagnostics.A_parameter_property_is_only_allowed_in_a_constructor_implementation);
+                }
+            }
+            if (node.questionToken && ts.isBindingPattern(node.name) && func.body) {
+                error(node, ts.Diagnostics.A_binding_pattern_parameter_cannot_be_optional_in_an_implementation_signature);
+            }
+            if (node.name && ts.isIdentifier(node.name) && (node.name.escapedText === "this" || node.name.escapedText === "new")) {
+                if (func.parameters.indexOf(node) !== 0) {
+                    error(node, ts.Diagnostics.A_0_parameter_must_be_the_first_parameter, node.name.escapedText);
+                }
+                if (func.kind === 155 /* Constructor */ || func.kind === 159 /* ConstructSignature */ || func.kind === 164 /* ConstructorType */) {
+                    error(node, ts.Diagnostics.A_constructor_cannot_have_a_this_parameter);
+                }
+            }
+            // Only check rest parameter type if it's not a binding pattern. Since binding patterns are
+            // not allowed in a rest parameter, we already have an error from checkGrammarParameterList.
+            if (node.dotDotDotToken && !ts.isBindingPattern(node.name) && !isArrayType(getTypeOfSymbol(node.symbol))) {
+                error(node, ts.Diagnostics.A_rest_parameter_must_be_of_an_array_type);
+            }
+        }
+        function getTypePredicateParameterIndex(parameterList, parameter) {
+            if (parameterList) {
+                for (var i = 0; i < parameterList.length; i++) {
+                    var param = parameterList[i];
+                    if (param.name.kind === 71 /* Identifier */ && param.name.escapedText === parameter.escapedText) {
+                        return i;
+                    }
+                }
+            }
+            return -1;
+        }
+        function checkTypePredicate(node) {
+            var parent = getTypePredicateParent(node);
+            if (!parent) {
+                // The parent must not be valid.
+                error(node, ts.Diagnostics.A_type_predicate_is_only_allowed_in_return_type_position_for_functions_and_methods);
+                return;
+            }
+            var typePredicate = getTypePredicateOfSignature(getSignatureFromDeclaration(parent));
+            if (!typePredicate) {
+                return;
+            }
+            checkSourceElement(node.type);
+            var parameterName = node.parameterName;
+            if (ts.isThisTypePredicate(typePredicate)) {
+                getTypeFromThisTypeNode(parameterName);
+            }
+            else {
+                if (typePredicate.parameterIndex >= 0) {
+                    if (parent.parameters[typePredicate.parameterIndex].dotDotDotToken) {
+                        error(parameterName, ts.Diagnostics.A_type_predicate_cannot_reference_a_rest_parameter);
+                    }
+                    else {
+                        var leadingError = function () { return ts.chainDiagnosticMessages(/*details*/ undefined, ts.Diagnostics.A_type_predicate_s_type_must_be_assignable_to_its_parameter_s_type); };
+                        checkTypeAssignableTo(typePredicate.type, getTypeOfNode(parent.parameters[typePredicate.parameterIndex]), // TODO: GH#18217
+                        node.type, 
+                        /*headMessage*/ undefined, leadingError);
+                    }
+                }
+                else if (parameterName) {
+                    var hasReportedError = false;
+                    for (var _i = 0, _a = parent.parameters; _i < _a.length; _i++) {
+                        var name = _a[_i].name;
+                        if (ts.isBindingPattern(name) &&
+                            checkIfTypePredicateVariableIsDeclaredInBindingPattern(name, parameterName, typePredicate.parameterName)) {
+                            hasReportedError = true;
+                            break;
+                        }
+                    }
+                    if (!hasReportedError) {
+                        error(node.parameterName, ts.Diagnostics.Cannot_find_parameter_0, typePredicate.parameterName);
+                    }
+                }
+            }
+        }
+        function getTypePredicateParent(node) {
+            switch (node.parent.kind) {
+                case 193 /* ArrowFunction */:
+                case 158 /* CallSignature */:
+                case 234 /* FunctionDeclaration */:
+                case 192 /* FunctionExpression */:
+                case 163 /* FunctionType */:
+                case 154 /* MethodDeclaration */:
+                case 153 /* MethodSignature */:
+                    var parent = node.parent;
+                    if (node === parent.type) {
+                        return parent;
+                    }
+            }
+        }
+        function checkIfTypePredicateVariableIsDeclaredInBindingPattern(pattern, predicateVariableNode, predicateVariableName) {
+            for (var _i = 0, _a = pattern.elements; _i < _a.length; _i++) {
+                var element = _a[_i];
+                if (ts.isOmittedExpression(element)) {
+                    continue;
+                }
+                var name = element.name;
+                if (name.kind === 71 /* Identifier */ && name.escapedText === predicateVariableName) {
+                    error(predicateVariableNode, ts.Diagnostics.A_type_predicate_cannot_reference_element_0_in_a_binding_pattern, predicateVariableName);
+                    return true;
+                }
+                else if (name.kind === 181 /* ArrayBindingPattern */ || name.kind === 180 /* ObjectBindingPattern */) {
+                    if (checkIfTypePredicateVariableIsDeclaredInBindingPattern(name, predicateVariableNode, predicateVariableName)) {
+                        return true;
+                    }
+                }
+            }
+        }
+        function checkSignatureDeclaration(node) {
+            // Grammar checking
+            if (node.kind === 160 /* IndexSignature */) {
+                checkGrammarIndexSignature(node);
+            }
+            // TODO (yuisu): Remove this check in else-if when SyntaxKind.Construct is moved and ambient context is handled
+            else if (node.kind === 163 /* FunctionType */ || node.kind === 234 /* FunctionDeclaration */ || node.kind === 164 /* ConstructorType */ ||
+                node.kind === 158 /* CallSignature */ || node.kind === 155 /* Constructor */ ||
+                node.kind === 159 /* ConstructSignature */) {
+                checkGrammarFunctionLikeDeclaration(node);
+            }
+            var functionFlags = ts.getFunctionFlags(node);
+            if (!(functionFlags & 4 /* Invalid */)) {
+                // Async generators prior to ESNext require the __await and __asyncGenerator helpers
+                if ((functionFlags & 3 /* AsyncGenerator */) === 3 /* AsyncGenerator */ && languageVersion < 6 /* ESNext */) {
+                    checkExternalEmitHelpers(node, 6144 /* AsyncGeneratorIncludes */);
+                }
+                // Async functions prior to ES2017 require the __awaiter helper
+                if ((functionFlags & 3 /* AsyncGenerator */) === 2 /* Async */ && languageVersion < 4 /* ES2017 */) {
+                    checkExternalEmitHelpers(node, 64 /* Awaiter */);
+                }
+                // Generator functions, Async functions, and Async Generator functions prior to
+                // ES2015 require the __generator helper
+                if ((functionFlags & 3 /* AsyncGenerator */) !== 0 /* Normal */ && languageVersion < 2 /* ES2015 */) {
+                    checkExternalEmitHelpers(node, 128 /* Generator */);
+                }
+            }
+            checkTypeParameters(node.typeParameters);
+            ts.forEach(node.parameters, checkParameter);
+            // TODO(rbuckton): Should we start checking JSDoc types?
+            if (node.type) {
+                checkSourceElement(node.type);
+            }
+            if (produceDiagnostics) {
+                checkCollisionWithArgumentsInGeneratedCode(node);
+                var returnTypeNode = ts.getEffectiveReturnTypeNode(node);
+                if (noImplicitAny && !returnTypeNode) {
+                    switch (node.kind) {
+                        case 159 /* ConstructSignature */:
+                            error(node, ts.Diagnostics.Construct_signature_which_lacks_return_type_annotation_implicitly_has_an_any_return_type);
+                            break;
+                        case 158 /* CallSignature */:
+                            error(node, ts.Diagnostics.Call_signature_which_lacks_return_type_annotation_implicitly_has_an_any_return_type);
+                            break;
+                    }
+                }
+                if (returnTypeNode) {
+                    var functionFlags_1 = ts.getFunctionFlags(node);
+                    if ((functionFlags_1 & (4 /* Invalid */ | 1 /* Generator */)) === 1 /* Generator */) {
+                        var returnType = getTypeFromTypeNode(returnTypeNode);
+                        if (returnType === voidType) {
+                            error(returnTypeNode, ts.Diagnostics.A_generator_cannot_have_a_void_type_annotation);
+                        }
+                        else {
+                            var generatorElementType = getIteratedTypeOfGenerator(returnType, (functionFlags_1 & 2 /* Async */) !== 0) || anyType;
+                            var iterableIteratorInstantiation = functionFlags_1 & 2 /* Async */
+                                ? createAsyncIterableIteratorType(generatorElementType) // AsyncGenerator function
+                                : createIterableIteratorType(generatorElementType); // Generator function
+                            // Naively, one could check that IterableIterator<any> is assignable to the return type annotation.
+                            // However, that would not catch the error in the following case.
+                            //
+                            //    interface BadGenerator extends Iterable<number>, Iterator<string> { }
+                            //    function* g(): BadGenerator { } // Iterable and Iterator have different types!
+                            //
+                            checkTypeAssignableTo(iterableIteratorInstantiation, returnType, returnTypeNode);
+                        }
+                    }
+                    else if ((functionFlags_1 & 3 /* AsyncGenerator */) === 2 /* Async */) {
+                        checkAsyncFunctionReturnType(node);
+                    }
+                }
+                if (node.kind !== 160 /* IndexSignature */ && node.kind !== 284 /* JSDocFunctionType */) {
+                    registerForUnusedIdentifiersCheck(node);
+                }
+            }
+        }
+        function checkClassForDuplicateDeclarations(node) {
+            var Declaration;
+            (function (Declaration) {
+                Declaration[Declaration["Getter"] = 1] = "Getter";
+                Declaration[Declaration["Setter"] = 2] = "Setter";
+                Declaration[Declaration["Method"] = 4] = "Method";
+                Declaration[Declaration["Property"] = 3] = "Property";
+            })(Declaration || (Declaration = {}));
+            var instanceNames = ts.createUnderscoreEscapedMap();
+            var staticNames = ts.createUnderscoreEscapedMap();
+            for (var _i = 0, _a = node.members; _i < _a.length; _i++) {
+                var member = _a[_i];
+                if (member.kind === 155 /* Constructor */) {
+                    for (var _b = 0, _c = member.parameters; _b < _c.length; _b++) {
+                        var param = _c[_b];
+                        if (ts.isParameterPropertyDeclaration(param) && !ts.isBindingPattern(param.name)) {
+                            addName(instanceNames, param.name, param.name.escapedText, 3 /* Property */);
+                        }
+                    }
+                }
+                else {
+                    var isStatic = ts.hasModifier(member, 32 /* Static */);
+                    var names = isStatic ? staticNames : instanceNames;
+                    var name = member.name;
+                    var memberName = name && ts.getPropertyNameForPropertyNameNode(name);
+                    if (name && memberName) {
+                        switch (member.kind) {
+                            case 156 /* GetAccessor */:
+                                addName(names, name, memberName, 1 /* Getter */);
+                                break;
+                            case 157 /* SetAccessor */:
+                                addName(names, name, memberName, 2 /* Setter */);
+                                break;
+                            case 152 /* PropertyDeclaration */:
+                                addName(names, name, memberName, 3 /* Property */);
+                                break;
+                            case 154 /* MethodDeclaration */:
+                                addName(names, name, memberName, 4 /* Method */);
+                                break;
+                        }
+                    }
+                }
+            }
+            function addName(names, location, name, meaning) {
+                var prev = names.get(name);
+                if (prev) {
+                    if (prev & 4 /* Method */) {
+                        if (meaning !== 4 /* Method */) {
+                            error(location, ts.Diagnostics.Duplicate_identifier_0, ts.getTextOfNode(location));
+                        }
+                    }
+                    else if (prev & meaning) {
+                        error(location, ts.Diagnostics.Duplicate_identifier_0, ts.getTextOfNode(location));
+                    }
+                    else {
+                        names.set(name, prev | meaning);
+                    }
+                }
+                else {
+                    names.set(name, meaning);
+                }
+            }
+        }
+        /**
+         * Static members being set on a constructor function may conflict with built-in properties
+         * of Function. Esp. in ECMAScript 5 there are non-configurable and non-writable
+         * built-in properties. This check issues a transpile error when a class has a static
+         * member with the same name as a non-writable built-in property.
+         *
+         * @see http://www.ecma-international.org/ecma-262/5.1/#sec-15.3.3
+         * @see http://www.ecma-international.org/ecma-262/5.1/#sec-15.3.5
+         * @see http://www.ecma-international.org/ecma-262/6.0/#sec-properties-of-the-function-constructor
+         * @see http://www.ecma-international.org/ecma-262/6.0/#sec-function-instances
+         */
+        function checkClassForStaticPropertyNameConflicts(node) {
+            for (var _i = 0, _a = node.members; _i < _a.length; _i++) {
+                var member = _a[_i];
+                var memberNameNode = member.name;
+                var isStatic = ts.hasModifier(member, 32 /* Static */);
+                if (isStatic && memberNameNode) {
+                    var memberName = ts.getPropertyNameForPropertyNameNode(memberNameNode);
+                    switch (memberName) {
+                        case "name":
+                        case "length":
+                        case "caller":
+                        case "arguments":
+                        case "prototype":
+                            var message = ts.Diagnostics.Static_property_0_conflicts_with_built_in_property_Function_0_of_constructor_function_1;
+                            var className = getNameOfSymbolAsWritten(getSymbolOfNode(node));
+                            error(memberNameNode, message, memberName, className);
+                            break;
+                    }
+                }
+            }
+        }
+        function checkObjectTypeForDuplicateDeclarations(node) {
+            var names = ts.createMap();
+            for (var _i = 0, _a = node.members; _i < _a.length; _i++) {
+                var member = _a[_i];
+                if (member.kind === 151 /* PropertySignature */) {
+                    var memberName = void 0;
+                    var name = member.name;
+                    switch (name.kind) {
+                        case 9 /* StringLiteral */:
+                        case 8 /* NumericLiteral */:
+                            memberName = name.text;
+                            break;
+                        case 71 /* Identifier */:
+                            memberName = ts.idText(name);
+                            break;
+                        default:
+                            continue;
+                    }
+                    if (names.get(memberName)) {
+                        error(ts.getNameOfDeclaration(member.symbol.valueDeclaration), ts.Diagnostics.Duplicate_identifier_0, memberName);
+                        error(member.name, ts.Diagnostics.Duplicate_identifier_0, memberName);
+                    }
+                    else {
+                        names.set(memberName, true);
+                    }
+                }
+            }
+        }
+        function checkTypeForDuplicateIndexSignatures(node) {
+            if (node.kind === 236 /* InterfaceDeclaration */) {
+                var nodeSymbol = getSymbolOfNode(node);
+                // in case of merging interface declaration it is possible that we'll enter this check procedure several times for every declaration
+                // to prevent this run check only for the first declaration of a given kind
+                if (nodeSymbol.declarations.length > 0 && nodeSymbol.declarations[0] !== node) {
+                    return;
+                }
+            }
+            // TypeScript 1.0 spec (April 2014)
+            // 3.7.4: An object type can contain at most one string index signature and one numeric index signature.
+            // 8.5: A class declaration can have at most one string index member declaration and one numeric index member declaration
+            var indexSymbol = getIndexSymbol(getSymbolOfNode(node));
+            if (indexSymbol) {
+                var seenNumericIndexer = false;
+                var seenStringIndexer = false;
+                for (var _i = 0, _a = indexSymbol.declarations; _i < _a.length; _i++) {
+                    var decl = _a[_i];
+                    var declaration = decl;
+                    if (declaration.parameters.length === 1 && declaration.parameters[0].type) {
+                        switch (declaration.parameters[0].type.kind) {
+                            case 137 /* StringKeyword */:
+                                if (!seenStringIndexer) {
+                                    seenStringIndexer = true;
+                                }
+                                else {
+                                    error(declaration, ts.Diagnostics.Duplicate_string_index_signature);
+                                }
+                                break;
+                            case 134 /* NumberKeyword */:
+                                if (!seenNumericIndexer) {
+                                    seenNumericIndexer = true;
+                                }
+                                else {
+                                    error(declaration, ts.Diagnostics.Duplicate_number_index_signature);
+                                }
+                                break;
+                        }
+                    }
+                }
+            }
+        }
+        function checkPropertyDeclaration(node) {
+            // Grammar checking
+            if (!checkGrammarDecoratorsAndModifiers(node) && !checkGrammarProperty(node))
+                checkGrammarComputedPropertyName(node.name);
+            checkVariableLikeDeclaration(node);
+        }
+        function checkMethodDeclaration(node) {
+            // Grammar checking
+            if (!checkGrammarMethod(node))
+                checkGrammarComputedPropertyName(node.name);
+            // Grammar checking for modifiers is done inside the function checkGrammarFunctionLikeDeclaration
+            checkFunctionOrMethodDeclaration(node);
+            // Abstract methods cannot have an implementation.
+            // Extra checks are to avoid reporting multiple errors relating to the "abstractness" of the node.
+            if (ts.hasModifier(node, 128 /* Abstract */) && node.kind === 154 /* MethodDeclaration */ && node.body) {
+                error(node, ts.Diagnostics.Method_0_cannot_have_an_implementation_because_it_is_marked_abstract, ts.declarationNameToString(node.name));
+            }
+        }
+        function checkConstructorDeclaration(node) {
+            // Grammar check on signature of constructor and modifier of the constructor is done in checkSignatureDeclaration function.
+            checkSignatureDeclaration(node);
+            // Grammar check for checking only related to constructorDeclaration
+            if (!checkGrammarConstructorTypeParameters(node))
+                checkGrammarConstructorTypeAnnotation(node);
+            checkSourceElement(node.body);
+            var symbol = getSymbolOfNode(node);
+            var firstDeclaration = ts.getDeclarationOfKind(symbol, node.kind);
+            // Only type check the symbol once
+            if (node === firstDeclaration) {
+                checkFunctionOrConstructorSymbol(symbol);
+            }
+            // exit early in the case of signature - super checks are not relevant to them
+            if (ts.nodeIsMissing(node.body)) {
+                return;
+            }
+            if (!produceDiagnostics) {
+                return;
+            }
+            function isInstancePropertyWithInitializer(n) {
+                return n.kind === 152 /* PropertyDeclaration */ &&
+                    !ts.hasModifier(n, 32 /* Static */) &&
+                    !!n.initializer;
+            }
+            // TS 1.0 spec (April 2014): 8.3.2
+            // Constructors of classes with no extends clause may not contain super calls, whereas
+            // constructors of derived classes must contain at least one super call somewhere in their function body.
+            var containingClassDecl = node.parent;
+            if (ts.getClassExtendsHeritageClauseElement(containingClassDecl)) {
+                captureLexicalThis(node.parent, containingClassDecl);
+                var classExtendsNull = classDeclarationExtendsNull(containingClassDecl);
+                var superCall = getSuperCallInConstructor(node);
+                if (superCall) {
+                    if (classExtendsNull) {
+                        error(superCall, ts.Diagnostics.A_constructor_cannot_contain_a_super_call_when_its_class_extends_null);
+                    }
+                    // The first statement in the body of a constructor (excluding prologue directives) must be a super call
+                    // if both of the following are true:
+                    // - The containing class is a derived class.
+                    // - The constructor declares parameter properties
+                    //   or the containing class declares instance member variables with initializers.
+                    var superCallShouldBeFirst = ts.some(node.parent.members, isInstancePropertyWithInitializer) ||
+                        ts.some(node.parameters, function (p) { return ts.hasModifier(p, 92 /* ParameterPropertyModifier */); });
+                    // Skip past any prologue directives to find the first statement
+                    // to ensure that it was a super call.
+                    if (superCallShouldBeFirst) {
+                        var statements = node.body.statements;
+                        var superCallStatement = void 0;
+                        for (var _i = 0, statements_2 = statements; _i < statements_2.length; _i++) {
+                            var statement = statements_2[_i];
+                            if (statement.kind === 216 /* ExpressionStatement */ && ts.isSuperCall(statement.expression)) {
+                                superCallStatement = statement;
+                                break;
+                            }
+                            if (!ts.isPrologueDirective(statement)) {
+                                break;
+                            }
+                        }
+                        if (!superCallStatement) {
+                            error(node, ts.Diagnostics.A_super_call_must_be_the_first_statement_in_the_constructor_when_a_class_contains_initialized_properties_or_has_parameter_properties);
+                        }
+                    }
+                }
+                else if (!classExtendsNull) {
+                    error(node, ts.Diagnostics.Constructors_for_derived_classes_must_contain_a_super_call);
+                }
+            }
+        }
+        function checkAccessorDeclaration(node) {
+            if (produceDiagnostics) {
+                // Grammar checking accessors
+                if (!checkGrammarFunctionLikeDeclaration(node) && !checkGrammarAccessor(node))
+                    checkGrammarComputedPropertyName(node.name);
+                checkDecorators(node);
+                checkSignatureDeclaration(node);
+                if (node.kind === 156 /* GetAccessor */) {
+                    if (!(node.flags & 4194304 /* Ambient */) && ts.nodeIsPresent(node.body) && (node.flags & 128 /* HasImplicitReturn */)) {
+                        if (!(node.flags & 256 /* HasExplicitReturn */)) {
+                            error(node.name, ts.Diagnostics.A_get_accessor_must_return_a_value);
+                        }
+                    }
+                }
+                // Do not use hasDynamicName here, because that returns false for well known symbols.
+                // We want to perform checkComputedPropertyName for all computed properties, including
+                // well known symbols.
+                if (node.name.kind === 147 /* ComputedPropertyName */) {
+                    checkComputedPropertyName(node.name);
+                }
+                if (!hasNonBindableDynamicName(node)) {
+                    // TypeScript 1.0 spec (April 2014): 8.4.3
+                    // Accessors for the same member name must specify the same accessibility.
+                    var otherKind = node.kind === 156 /* GetAccessor */ ? 157 /* SetAccessor */ : 156 /* GetAccessor */;
+                    var otherAccessor = ts.getDeclarationOfKind(getSymbolOfNode(node), otherKind);
+                    if (otherAccessor) {
+                        var nodeFlags = ts.getModifierFlags(node);
+                        var otherFlags = ts.getModifierFlags(otherAccessor);
+                        if ((nodeFlags & 28 /* AccessibilityModifier */) !== (otherFlags & 28 /* AccessibilityModifier */)) {
+                            error(node.name, ts.Diagnostics.Getter_and_setter_accessors_do_not_agree_in_visibility);
+                        }
+                        if ((nodeFlags & 128 /* Abstract */) !== (otherFlags & 128 /* Abstract */)) {
+                            error(node.name, ts.Diagnostics.Accessors_must_both_be_abstract_or_non_abstract);
+                        }
+                        // TypeScript 1.0 spec (April 2014): 4.5
+                        // If both accessors include type annotations, the specified types must be identical.
+                        checkAccessorDeclarationTypesIdentical(node, otherAccessor, getAnnotatedAccessorType, ts.Diagnostics.get_and_set_accessor_must_have_the_same_type);
+                        checkAccessorDeclarationTypesIdentical(node, otherAccessor, getThisTypeOfDeclaration, ts.Diagnostics.get_and_set_accessor_must_have_the_same_this_type);
+                    }
+                }
+                var returnType = getTypeOfAccessors(getSymbolOfNode(node));
+                if (node.kind === 156 /* GetAccessor */) {
+                    checkAllCodePathsInNonVoidFunctionReturnOrThrow(node, returnType);
+                }
+            }
+            checkSourceElement(node.body);
+        }
+        function checkAccessorDeclarationTypesIdentical(first, second, getAnnotatedType, message) {
+            var firstType = getAnnotatedType(first);
+            var secondType = getAnnotatedType(second);
+            if (firstType && secondType && !isTypeIdenticalTo(firstType, secondType)) {
+                error(first, message);
+            }
+        }
+        function checkMissingDeclaration(node) {
+            checkDecorators(node);
+        }
+        function getEffectiveTypeArguments(node, typeParameters) {
+            return fillMissingTypeArguments(ts.map(node.typeArguments, getTypeFromTypeNode), typeParameters, getMinTypeArgumentCount(typeParameters), ts.isInJavaScriptFile(node));
+        }
+        function checkTypeArgumentConstraints(node, typeParameters) {
+            var typeArguments;
+            var mapper;
+            var result = true;
+            for (var i = 0; i < typeParameters.length; i++) {
+                var constraint = getConstraintOfTypeParameter(typeParameters[i]);
+                if (constraint) {
+                    if (!typeArguments) {
+                        typeArguments = getEffectiveTypeArguments(node, typeParameters);
+                        mapper = createTypeMapper(typeParameters, typeArguments);
+                    }
+                    result = result && checkTypeAssignableTo(typeArguments[i], instantiateType(constraint, mapper), node.typeArguments[i], ts.Diagnostics.Type_0_does_not_satisfy_the_constraint_1);
+                }
+            }
+            return result;
+        }
+        function getTypeParametersForTypeReference(node) {
+            var type = getTypeFromTypeReference(node);
+            if (type !== errorType) {
+                var symbol = getNodeLinks(node).resolvedSymbol;
+                if (symbol) {
+                    return symbol.flags & 524288 /* TypeAlias */ && getSymbolLinks(symbol).typeParameters ||
+                        (ts.getObjectFlags(type) & 4 /* Reference */ ? type.target.localTypeParameters : undefined);
+                }
+            }
+            return undefined;
+        }
+        function checkTypeReferenceNode(node) {
+            checkGrammarTypeArguments(node, node.typeArguments);
+            if (node.kind === 162 /* TypeReference */ && node.typeName.jsdocDotPos !== undefined && !ts.isInJavaScriptFile(node) && !ts.isInJSDoc(node)) {
+                grammarErrorAtPos(node, node.typeName.jsdocDotPos, 1, ts.Diagnostics.JSDoc_types_can_only_be_used_inside_documentation_comments);
+            }
+            var type = getTypeFromTypeReference(node);
+            if (type !== errorType) {
+                if (node.typeArguments) {
+                    // Do type argument local checks only if referenced type is successfully resolved
+                    ts.forEach(node.typeArguments, checkSourceElement);
+                    if (produceDiagnostics) {
+                        var typeParameters = getTypeParametersForTypeReference(node);
+                        if (typeParameters) {
+                            checkTypeArgumentConstraints(node, typeParameters);
+                        }
+                    }
+                }
+                if (type.flags & 32 /* Enum */ && getNodeLinks(node).resolvedSymbol.flags & 8 /* EnumMember */) {
+                    error(node, ts.Diagnostics.Enum_type_0_has_members_with_initializers_that_are_not_literals, typeToString(type));
+                }
+            }
+        }
+        function getTypeArgumentConstraint(node) {
+            var typeReferenceNode = ts.tryCast(node.parent, ts.isTypeReferenceType);
+            if (!typeReferenceNode)
+                return undefined;
+            var typeParameters = getTypeParametersForTypeReference(typeReferenceNode); // TODO: GH#18217
+            var constraint = getConstraintOfTypeParameter(typeParameters[typeReferenceNode.typeArguments.indexOf(node)]);
+            return constraint && instantiateType(constraint, createTypeMapper(typeParameters, getEffectiveTypeArguments(typeReferenceNode, typeParameters)));
+        }
+        function checkTypeQuery(node) {
+            getTypeFromTypeQueryNode(node);
+        }
+        function checkTypeLiteral(node) {
+            ts.forEach(node.members, checkSourceElement);
+            if (produceDiagnostics) {
+                var type = getTypeFromTypeLiteralOrFunctionOrConstructorTypeNode(node);
+                checkIndexConstraints(type);
+                checkTypeForDuplicateIndexSignatures(node);
+                checkObjectTypeForDuplicateDeclarations(node);
+            }
+        }
+        function checkArrayType(node) {
+            checkSourceElement(node.elementType);
+        }
+        function checkTupleType(node) {
+            // Grammar checking
+            var hasErrorFromDisallowedTrailingComma = checkGrammarForDisallowedTrailingComma(node.elementTypes);
+            if (!hasErrorFromDisallowedTrailingComma && node.elementTypes.length === 0) {
+                grammarErrorOnNode(node, ts.Diagnostics.A_tuple_type_element_list_cannot_be_empty);
+            }
+            ts.forEach(node.elementTypes, checkSourceElement);
+        }
+        function checkUnionOrIntersectionType(node) {
+            ts.forEach(node.types, checkSourceElement);
+        }
+        function checkIndexedAccessIndexType(type, accessNode) {
+            if (!(type.flags & 2097152 /* IndexedAccess */)) {
+                return type;
+            }
+            // Check if the index type is assignable to 'keyof T' for the object type.
+            var objectType = type.objectType;
+            var indexType = type.indexType;
+            if (isTypeAssignableTo(indexType, getIndexType(objectType, /*stringsOnly*/ false))) {
+                if (accessNode.kind === 186 /* ElementAccessExpression */ && ts.isAssignmentTarget(accessNode) &&
+                    ts.getObjectFlags(objectType) & 32 /* Mapped */ && getMappedTypeModifiers(objectType) & 1 /* IncludeReadonly */) {
+                    error(accessNode, ts.Diagnostics.Index_signature_in_type_0_only_permits_reading, typeToString(objectType));
+                }
+                return type;
+            }
+            // Check if we're indexing with a numeric type and if either object or index types
+            // is a generic type with a constraint that has a numeric index signature.
+            if (getIndexInfoOfType(getApparentType(objectType), 1 /* Number */) && isTypeAssignableToKind(indexType, 168 /* NumberLike */)) {
+                return type;
+            }
+            error(accessNode, ts.Diagnostics.Type_0_cannot_be_used_to_index_type_1, typeToString(indexType), typeToString(objectType));
+            return type;
+        }
+        function checkIndexedAccessType(node) {
+            checkSourceElement(node.objectType);
+            checkSourceElement(node.indexType);
+            checkIndexedAccessIndexType(getTypeFromIndexedAccessTypeNode(node), node);
+        }
+        function checkMappedType(node) {
+            checkSourceElement(node.typeParameter);
+            checkSourceElement(node.type);
+            if (noImplicitAny && !node.type) {
+                reportImplicitAnyError(node, anyType);
+            }
+            var type = getTypeFromMappedTypeNode(node);
+            var constraintType = getConstraintTypeFromMappedType(type);
+            checkTypeAssignableTo(constraintType, keyofConstraintType, node.typeParameter.constraint);
+        }
+        function checkTypeOperator(node) {
+            checkGrammarTypeOperatorNode(node);
+            checkSourceElement(node.type);
+        }
+        function checkConditionalType(node) {
+            ts.forEachChild(node, checkSourceElement);
+        }
+        function checkInferType(node) {
+            if (!ts.findAncestor(node, function (n) { return n.parent && n.parent.kind === 171 /* ConditionalType */ && n.parent.extendsType === n; })) {
+                grammarErrorOnNode(node, ts.Diagnostics.infer_declarations_are_only_permitted_in_the_extends_clause_of_a_conditional_type);
+            }
+            checkSourceElement(node.typeParameter);
+        }
+        function checkImportType(node) {
+            checkSourceElement(node.argument);
+            getTypeFromTypeNode(node);
+        }
+        function isPrivateWithinAmbient(node) {
+            return ts.hasModifier(node, 8 /* Private */) && !!(node.flags & 4194304 /* Ambient */);
+        }
+        function getEffectiveDeclarationFlags(n, flagsToCheck) {
+            var flags = ts.getCombinedModifierFlags(n);
+            // children of classes (even ambient classes) should not be marked as ambient or export
+            // because those flags have no useful semantics there.
+            if (n.parent.kind !== 236 /* InterfaceDeclaration */ &&
+                n.parent.kind !== 235 /* ClassDeclaration */ &&
+                n.parent.kind !== 205 /* ClassExpression */ &&
+                n.flags & 4194304 /* Ambient */) {
+                if (!(flags & 2 /* Ambient */) && !(ts.isModuleBlock(n.parent) && ts.isModuleDeclaration(n.parent.parent) && ts.isGlobalScopeAugmentation(n.parent.parent))) {
+                    // It is nested in an ambient context, which means it is automatically exported
+                    flags |= 1 /* Export */;
+                }
+                flags |= 2 /* Ambient */;
+            }
+            return flags & flagsToCheck;
+        }
+        function checkFunctionOrConstructorSymbol(symbol) {
+            if (!produceDiagnostics) {
+                return;
+            }
+            function getCanonicalOverload(overloads, implementation) {
+                // Consider the canonical set of flags to be the flags of the bodyDeclaration or the first declaration
+                // Error on all deviations from this canonical set of flags
+                // The caveat is that if some overloads are defined in lib.d.ts, we don't want to
+                // report the errors on those. To achieve this, we will say that the implementation is
+                // the canonical signature only if it is in the same container as the first overload
+                var implementationSharesContainerWithFirstOverload = implementation !== undefined && implementation.parent === overloads[0].parent;
+                return implementationSharesContainerWithFirstOverload ? implementation : overloads[0];
+            }
+            function checkFlagAgreementBetweenOverloads(overloads, implementation, flagsToCheck, someOverloadFlags, allOverloadFlags) {
+                // Error if some overloads have a flag that is not shared by all overloads. To find the
+                // deviations, we XOR someOverloadFlags with allOverloadFlags
+                var someButNotAllOverloadFlags = someOverloadFlags ^ allOverloadFlags;
+                if (someButNotAllOverloadFlags !== 0) {
+                    var canonicalFlags_1 = getEffectiveDeclarationFlags(getCanonicalOverload(overloads, implementation), flagsToCheck);
+                    ts.forEach(overloads, function (o) {
+                        var deviation = getEffectiveDeclarationFlags(o, flagsToCheck) ^ canonicalFlags_1;
+                        if (deviation & 1 /* Export */) {
+                            error(ts.getNameOfDeclaration(o), ts.Diagnostics.Overload_signatures_must_all_be_exported_or_non_exported);
+                        }
+                        else if (deviation & 2 /* Ambient */) {
+                            error(ts.getNameOfDeclaration(o), ts.Diagnostics.Overload_signatures_must_all_be_ambient_or_non_ambient);
+                        }
+                        else if (deviation & (8 /* Private */ | 16 /* Protected */)) {
+                            error(ts.getNameOfDeclaration(o) || o, ts.Diagnostics.Overload_signatures_must_all_be_public_private_or_protected);
+                        }
+                        else if (deviation & 128 /* Abstract */) {
+                            error(ts.getNameOfDeclaration(o), ts.Diagnostics.Overload_signatures_must_all_be_abstract_or_non_abstract);
+                        }
+                    });
+                }
+            }
+            function checkQuestionTokenAgreementBetweenOverloads(overloads, implementation, someHaveQuestionToken, allHaveQuestionToken) {
+                if (someHaveQuestionToken !== allHaveQuestionToken) {
+                    var canonicalHasQuestionToken_1 = ts.hasQuestionToken(getCanonicalOverload(overloads, implementation));
+                    ts.forEach(overloads, function (o) {
+                        var deviation = ts.hasQuestionToken(o) !== canonicalHasQuestionToken_1;
+                        if (deviation) {
+                            error(ts.getNameOfDeclaration(o), ts.Diagnostics.Overload_signatures_must_all_be_optional_or_required);
+                        }
+                    });
+                }
+            }
+            var flagsToCheck = 1 /* Export */ | 2 /* Ambient */ | 8 /* Private */ | 16 /* Protected */ | 128 /* Abstract */;
+            var someNodeFlags = 0 /* None */;
+            var allNodeFlags = flagsToCheck;
+            var someHaveQuestionToken = false;
+            var allHaveQuestionToken = true;
+            var hasOverloads = false;
+            var bodyDeclaration;
+            var lastSeenNonAmbientDeclaration;
+            var previousDeclaration;
+            var declarations = symbol.declarations;
+            var isConstructor = (symbol.flags & 16384 /* Constructor */) !== 0;
+            function reportImplementationExpectedError(node) {
+                if (node.name && ts.nodeIsMissing(node.name)) {
+                    return;
+                }
+                var seen = false;
+                var subsequentNode = ts.forEachChild(node.parent, function (c) {
+                    if (seen) {
+                        return c;
+                    }
+                    else {
+                        seen = c === node;
+                    }
+                });
+                // We may be here because of some extra nodes between overloads that could not be parsed into a valid node.
+                // In this case the subsequent node is not really consecutive (.pos !== node.end), and we must ignore it here.
+                if (subsequentNode && subsequentNode.pos === node.end) {
+                    if (subsequentNode.kind === node.kind) {
+                        var errorNode_1 = subsequentNode.name || subsequentNode;
+                        // TODO: GH#17345: These are methods, so handle computed name case. (`Always allowing computed property names is *not* the correct behavior!)
+                        var subsequentName = subsequentNode.name;
+                        if (node.name && subsequentName &&
+                            (ts.isComputedPropertyName(node.name) && ts.isComputedPropertyName(subsequentName) ||
+                                !ts.isComputedPropertyName(node.name) && !ts.isComputedPropertyName(subsequentName) && ts.getEscapedTextOfIdentifierOrLiteral(node.name) === ts.getEscapedTextOfIdentifierOrLiteral(subsequentName))) {
+                            var reportError = (node.kind === 154 /* MethodDeclaration */ || node.kind === 153 /* MethodSignature */) &&
+                                ts.hasModifier(node, 32 /* Static */) !== ts.hasModifier(subsequentNode, 32 /* Static */);
+                            // we can get here in two cases
+                            // 1. mixed static and instance class members
+                            // 2. something with the same name was defined before the set of overloads that prevents them from merging
+                            // here we'll report error only for the first case since for second we should already report error in binder
+                            if (reportError) {
+                                var diagnostic = ts.hasModifier(node, 32 /* Static */) ? ts.Diagnostics.Function_overload_must_be_static : ts.Diagnostics.Function_overload_must_not_be_static;
+                                error(errorNode_1, diagnostic);
+                            }
+                            return;
+                        }
+                        else if (ts.nodeIsPresent(subsequentNode.body)) {
+                            error(errorNode_1, ts.Diagnostics.Function_implementation_name_must_be_0, ts.declarationNameToString(node.name));
+                            return;
+                        }
+                    }
+                }
+                var errorNode = node.name || node;
+                if (isConstructor) {
+                    error(errorNode, ts.Diagnostics.Constructor_implementation_is_missing);
+                }
+                else {
+                    // Report different errors regarding non-consecutive blocks of declarations depending on whether
+                    // the node in question is abstract.
+                    if (ts.hasModifier(node, 128 /* Abstract */)) {
+                        error(errorNode, ts.Diagnostics.All_declarations_of_an_abstract_method_must_be_consecutive);
+                    }
+                    else {
+                        error(errorNode, ts.Diagnostics.Function_implementation_is_missing_or_not_immediately_following_the_declaration);
+                    }
+                }
+            }
+            var duplicateFunctionDeclaration = false;
+            var multipleConstructorImplementation = false;
+            for (var _i = 0, declarations_4 = declarations; _i < declarations_4.length; _i++) {
+                var current = declarations_4[_i];
+                var node = current;
+                var inAmbientContext = node.flags & 4194304 /* Ambient */;
+                var inAmbientContextOrInterface = node.parent.kind === 236 /* InterfaceDeclaration */ || node.parent.kind === 166 /* TypeLiteral */ || inAmbientContext;
+                if (inAmbientContextOrInterface) {
+                    // check if declarations are consecutive only if they are non-ambient
+                    // 1. ambient declarations can be interleaved
+                    // i.e. this is legal
+                    //     declare function foo();
+                    //     declare function bar();
+                    //     declare function foo();
+                    // 2. mixing ambient and non-ambient declarations is a separate error that will be reported - do not want to report an extra one
+                    previousDeclaration = undefined;
+                }
+                if (node.kind === 234 /* FunctionDeclaration */ || node.kind === 154 /* MethodDeclaration */ || node.kind === 153 /* MethodSignature */ || node.kind === 155 /* Constructor */) {
+                    var currentNodeFlags = getEffectiveDeclarationFlags(node, flagsToCheck);
+                    someNodeFlags |= currentNodeFlags;
+                    allNodeFlags &= currentNodeFlags;
+                    someHaveQuestionToken = someHaveQuestionToken || ts.hasQuestionToken(node);
+                    allHaveQuestionToken = allHaveQuestionToken && ts.hasQuestionToken(node);
+                    if (ts.nodeIsPresent(node.body) && bodyDeclaration) {
+                        if (isConstructor) {
+                            multipleConstructorImplementation = true;
+                        }
+                        else {
+                            duplicateFunctionDeclaration = true;
+                        }
+                    }
+                    else if (previousDeclaration && previousDeclaration.parent === node.parent && previousDeclaration.end !== node.pos) {
+                        reportImplementationExpectedError(previousDeclaration);
+                    }
+                    if (ts.nodeIsPresent(node.body)) {
+                        if (!bodyDeclaration) {
+                            bodyDeclaration = node;
+                        }
+                    }
+                    else {
+                        hasOverloads = true;
+                    }
+                    previousDeclaration = node;
+                    if (!inAmbientContextOrInterface) {
+                        lastSeenNonAmbientDeclaration = node;
+                    }
+                }
+            }
+            if (multipleConstructorImplementation) {
+                ts.forEach(declarations, function (declaration) {
+                    error(declaration, ts.Diagnostics.Multiple_constructor_implementations_are_not_allowed);
+                });
+            }
+            if (duplicateFunctionDeclaration) {
+                ts.forEach(declarations, function (declaration) {
+                    error(ts.getNameOfDeclaration(declaration), ts.Diagnostics.Duplicate_function_implementation);
+                });
+            }
+            // Abstract methods can't have an implementation -- in particular, they don't need one.
+            if (lastSeenNonAmbientDeclaration && !lastSeenNonAmbientDeclaration.body &&
+                !ts.hasModifier(lastSeenNonAmbientDeclaration, 128 /* Abstract */) && !lastSeenNonAmbientDeclaration.questionToken) {
+                reportImplementationExpectedError(lastSeenNonAmbientDeclaration);
+            }
+            if (hasOverloads) {
+                checkFlagAgreementBetweenOverloads(declarations, bodyDeclaration, flagsToCheck, someNodeFlags, allNodeFlags);
+                checkQuestionTokenAgreementBetweenOverloads(declarations, bodyDeclaration, someHaveQuestionToken, allHaveQuestionToken);
+                if (bodyDeclaration) {
+                    var signatures = getSignaturesOfSymbol(symbol);
+                    var bodySignature = getSignatureFromDeclaration(bodyDeclaration);
+                    for (var _a = 0, signatures_7 = signatures; _a < signatures_7.length; _a++) {
+                        var signature = signatures_7[_a];
+                        if (!isImplementationCompatibleWithOverload(bodySignature, signature)) {
+                            error(signature.declaration, ts.Diagnostics.Overload_signature_is_not_compatible_with_function_implementation);
+                            break;
+                        }
+                    }
+                }
+            }
+        }
+        function checkExportsOnMergedDeclarations(node) {
+            if (!produceDiagnostics) {
+                return;
+            }
+            // if localSymbol is defined on node then node itself is exported - check is required
+            var symbol = node.localSymbol;
+            if (!symbol) {
+                // local symbol is undefined => this declaration is non-exported.
+                // however symbol might contain other declarations that are exported
+                symbol = getSymbolOfNode(node);
+                if (!symbol.exportSymbol) {
+                    // this is a pure local symbol (all declarations are non-exported) - no need to check anything
+                    return;
+                }
+            }
+            // run the check only for the first declaration in the list
+            if (ts.getDeclarationOfKind(symbol, node.kind) !== node) {
+                return;
+            }
+            var exportedDeclarationSpaces = 0 /* None */;
+            var nonExportedDeclarationSpaces = 0 /* None */;
+            var defaultExportedDeclarationSpaces = 0 /* None */;
+            for (var _i = 0, _a = symbol.declarations; _i < _a.length; _i++) {
+                var d = _a[_i];
+                var declarationSpaces = getDeclarationSpaces(d);
+                var effectiveDeclarationFlags = getEffectiveDeclarationFlags(d, 1 /* Export */ | 512 /* Default */);
+                if (effectiveDeclarationFlags & 1 /* Export */) {
+                    if (effectiveDeclarationFlags & 512 /* Default */) {
+                        defaultExportedDeclarationSpaces |= declarationSpaces;
+                    }
+                    else {
+                        exportedDeclarationSpaces |= declarationSpaces;
+                    }
+                }
+                else {
+                    nonExportedDeclarationSpaces |= declarationSpaces;
+                }
+            }
+            // Spaces for anything not declared a 'default export'.
+            var nonDefaultExportedDeclarationSpaces = exportedDeclarationSpaces | nonExportedDeclarationSpaces;
+            var commonDeclarationSpacesForExportsAndLocals = exportedDeclarationSpaces & nonExportedDeclarationSpaces;
+            var commonDeclarationSpacesForDefaultAndNonDefault = defaultExportedDeclarationSpaces & nonDefaultExportedDeclarationSpaces;
+            if (commonDeclarationSpacesForExportsAndLocals || commonDeclarationSpacesForDefaultAndNonDefault) {
+                // declaration spaces for exported and non-exported declarations intersect
+                for (var _b = 0, _c = symbol.declarations; _b < _c.length; _b++) {
+                    var d = _c[_b];
+                    var declarationSpaces = getDeclarationSpaces(d);
+                    var name = ts.getNameOfDeclaration(d);
+                    // Only error on the declarations that contributed to the intersecting spaces.
+                    if (declarationSpaces & commonDeclarationSpacesForDefaultAndNonDefault) {
+                        error(name, ts.Diagnostics.Merged_declaration_0_cannot_include_a_default_export_declaration_Consider_adding_a_separate_export_default_0_declaration_instead, ts.declarationNameToString(name));
+                    }
+                    else if (declarationSpaces & commonDeclarationSpacesForExportsAndLocals) {
+                        error(name, ts.Diagnostics.Individual_declarations_in_merged_declaration_0_must_be_all_exported_or_all_local, ts.declarationNameToString(name));
+                    }
+                }
+            }
+            var DeclarationSpaces;
+            (function (DeclarationSpaces) {
+                DeclarationSpaces[DeclarationSpaces["None"] = 0] = "None";
+                DeclarationSpaces[DeclarationSpaces["ExportValue"] = 1] = "ExportValue";
+                DeclarationSpaces[DeclarationSpaces["ExportType"] = 2] = "ExportType";
+                DeclarationSpaces[DeclarationSpaces["ExportNamespace"] = 4] = "ExportNamespace";
+            })(DeclarationSpaces || (DeclarationSpaces = {}));
+            function getDeclarationSpaces(decl) {
+                var d = decl;
+                switch (d.kind) {
+                    case 236 /* InterfaceDeclaration */:
+                    case 237 /* TypeAliasDeclaration */:
+                    // A jsdoc typedef and callback are, by definition, type aliases
+                    case 297 /* JSDocTypedefTag */:
+                    case 292 /* JSDocCallbackTag */:
+                        return 2 /* ExportType */;
+                    case 239 /* ModuleDeclaration */:
+                        return ts.isAmbientModule(d) || ts.getModuleInstanceState(d) !== 0 /* NonInstantiated */
+                            ? 4 /* ExportNamespace */ | 1 /* ExportValue */
+                            : 4 /* ExportNamespace */;
+                    case 235 /* ClassDeclaration */:
+                    case 238 /* EnumDeclaration */:
+                        return 2 /* ExportType */ | 1 /* ExportValue */;
+                    case 274 /* SourceFile */:
+                        return 2 /* ExportType */ | 1 /* ExportValue */ | 4 /* ExportNamespace */;
+                    case 249 /* ExportAssignment */:
+                        // Export assigned entity name expressions act as aliases and should fall through, otherwise they export values
+                        if (!ts.isEntityNameExpression(d.expression)) {
+                            return 1 /* ExportValue */;
+                        }
+                        d = d.expression;
+                    /* falls through */
+                    // The below options all declare an Alias, which is allowed to merge with other values within the importing module
+                    case 243 /* ImportEqualsDeclaration */:
+                    case 246 /* NamespaceImport */:
+                    case 245 /* ImportClause */:
+                        var result_3 = 0 /* None */;
+                        var target = resolveAlias(getSymbolOfNode(d));
+                        ts.forEach(target.declarations, function (d) { result_3 |= getDeclarationSpaces(d); });
+                        return result_3;
+                    case 232 /* VariableDeclaration */:
+                    case 182 /* BindingElement */:
+                    case 234 /* FunctionDeclaration */:
+                    case 248 /* ImportSpecifier */: // https://github.com/Microsoft/TypeScript/pull/7591
+                        return 1 /* ExportValue */;
+                    default:
+                        return ts.Debug.fail(ts.Debug.showSyntaxKind(d));
+                }
+            }
+        }
+        function getAwaitedTypeOfPromise(type, errorNode, diagnosticMessage) {
+            var promisedType = getPromisedTypeOfPromise(type, errorNode);
+            return promisedType && getAwaitedType(promisedType, errorNode, diagnosticMessage);
+        }
+        /**
+         * Gets the "promised type" of a promise.
+         * @param type The type of the promise.
+         * @remarks The "promised type" of a type is the type of the "value" parameter of the "onfulfilled" callback.
+         */
+        function getPromisedTypeOfPromise(promise, errorNode) {
+            //
+            //  { // promise
+            //      then( // thenFunction
+            //          onfulfilled: ( // onfulfilledParameterType
+            //              value: T // valueParameterType
+            //          ) => any
+            //      ): any;
+            //  }
+            //
+            if (isTypeAny(promise)) {
+                return undefined;
+            }
+            var typeAsPromise = promise;
+            if (typeAsPromise.promisedTypeOfPromise) {
+                return typeAsPromise.promisedTypeOfPromise;
+            }
+            if (isReferenceToType(promise, getGlobalPromiseType(/*reportErrors*/ false))) {
+                return typeAsPromise.promisedTypeOfPromise = promise.typeArguments[0];
+            }
+            var thenFunction = getTypeOfPropertyOfType(promise, "then"); // TODO: GH#18217
+            if (isTypeAny(thenFunction)) {
+                return undefined;
+            }
+            var thenSignatures = thenFunction ? getSignaturesOfType(thenFunction, 0 /* Call */) : ts.emptyArray;
+            if (thenSignatures.length === 0) {
+                if (errorNode) {
+                    error(errorNode, ts.Diagnostics.A_promise_must_have_a_then_method);
+                }
+                return undefined;
+            }
+            var onfulfilledParameterType = getTypeWithFacts(getUnionType(ts.map(thenSignatures, getTypeOfFirstParameterOfSignature)), 524288 /* NEUndefinedOrNull */);
+            if (isTypeAny(onfulfilledParameterType)) {
+                return undefined;
+            }
+            var onfulfilledParameterSignatures = getSignaturesOfType(onfulfilledParameterType, 0 /* Call */);
+            if (onfulfilledParameterSignatures.length === 0) {
+                if (errorNode) {
+                    error(errorNode, ts.Diagnostics.The_first_parameter_of_the_then_method_of_a_promise_must_be_a_callback);
+                }
+                return undefined;
+            }
+            return typeAsPromise.promisedTypeOfPromise = getUnionType(ts.map(onfulfilledParameterSignatures, getTypeOfFirstParameterOfSignature), 2 /* Subtype */);
+        }
+        /**
+         * Gets the "awaited type" of a type.
+         * @param type The type to await.
+         * @remarks The "awaited type" of an expression is its "promised type" if the expression is a
+         * Promise-like type; otherwise, it is the type of the expression. This is used to reflect
+         * The runtime behavior of the `await` keyword.
+         */
+        function checkAwaitedType(type, errorNode, diagnosticMessage) {
+            return getAwaitedType(type, errorNode, diagnosticMessage) || errorType;
+        }
+        function getAwaitedType(type, errorNode, diagnosticMessage) {
+            var typeAsAwaitable = type;
+            if (typeAsAwaitable.awaitedTypeOfType) {
+                return typeAsAwaitable.awaitedTypeOfType;
+            }
+            if (isTypeAny(type)) {
+                return typeAsAwaitable.awaitedTypeOfType = type;
+            }
+            if (type.flags & 262144 /* Union */) {
+                var types = void 0;
+                for (var _i = 0, _a = type.types; _i < _a.length; _i++) {
+                    var constituentType = _a[_i];
+                    types = ts.append(types, getAwaitedType(constituentType, errorNode, diagnosticMessage));
+                }
+                if (!types) {
+                    return undefined;
+                }
+                return typeAsAwaitable.awaitedTypeOfType = getUnionType(types);
+            }
+            var promisedType = getPromisedTypeOfPromise(type);
+            if (promisedType) {
+                if (type.id === promisedType.id || awaitedTypeStack.indexOf(promisedType.id) >= 0) {
+                    // Verify that we don't have a bad actor in the form of a promise whose
+                    // promised type is the same as the promise type, or a mutually recursive
+                    // promise. If so, we return undefined as we cannot guess the shape. If this
+                    // were the actual case in the JavaScript, this Promise would never resolve.
+                    //
+                    // An example of a bad actor with a singly-recursive promise type might
+                    // be:
+                    //
+                    //  interface BadPromise {
+                    //      then(
+                    //          onfulfilled: (value: BadPromise) => any,
+                    //          onrejected: (error: any) => any): BadPromise;
+                    //  }
+                    // The above interface will pass the PromiseLike check, and return a
+                    // promised type of `BadPromise`. Since this is a self reference, we
+                    // don't want to keep recursing ad infinitum.
+                    //
+                    // An example of a bad actor in the form of a mutually-recursive
+                    // promise type might be:
+                    //
+                    //  interface BadPromiseA {
+                    //      then(
+                    //          onfulfilled: (value: BadPromiseB) => any,
+                    //          onrejected: (error: any) => any): BadPromiseB;
+                    //  }
+                    //
+                    //  interface BadPromiseB {
+                    //      then(
+                    //          onfulfilled: (value: BadPromiseA) => any,
+                    //          onrejected: (error: any) => any): BadPromiseA;
+                    //  }
+                    //
+                    if (errorNode) {
+                        error(errorNode, ts.Diagnostics.Type_is_referenced_directly_or_indirectly_in_the_fulfillment_callback_of_its_own_then_method);
+                    }
+                    return undefined;
+                }
+                // Keep track of the type we're about to unwrap to avoid bad recursive promise types.
+                // See the comments above for more information.
+                awaitedTypeStack.push(type.id);
+                var awaitedType = getAwaitedType(promisedType, errorNode, diagnosticMessage);
+                awaitedTypeStack.pop();
+                if (!awaitedType) {
+                    return undefined;
+                }
+                return typeAsAwaitable.awaitedTypeOfType = awaitedType;
+            }
+            // The type was not a promise, so it could not be unwrapped any further.
+            // As long as the type does not have a callable "then" property, it is
+            // safe to return the type; otherwise, an error will be reported in
+            // the call to getNonThenableType and we will return undefined.
+            //
+            // An example of a non-promise "thenable" might be:
+            //
+            //  await { then(): void {} }
+            //
+            // The "thenable" does not match the minimal definition for a promise. When
+            // a Promise/A+-compatible or ES6 promise tries to adopt this value, the promise
+            // will never settle. We treat this as an error to help flag an early indicator
+            // of a runtime problem. If the user wants to return this value from an async
+            // function, they would need to wrap it in some other value. If they want it to
+            // be treated as a promise, they can cast to <any>.
+            var thenFunction = getTypeOfPropertyOfType(type, "then");
+            if (thenFunction && getSignaturesOfType(thenFunction, 0 /* Call */).length > 0) {
+                if (errorNode) {
+                    if (!diagnosticMessage)
+                        return ts.Debug.fail();
+                    error(errorNode, diagnosticMessage);
+                }
+                return undefined;
+            }
+            return typeAsAwaitable.awaitedTypeOfType = type;
+        }
+        /**
+         * Checks the return type of an async function to ensure it is a compatible
+         * Promise implementation.
+         *
+         * This checks that an async function has a valid Promise-compatible return type,
+         * and returns the *awaited type* of the promise. An async function has a valid
+         * Promise-compatible return type if the resolved value of the return type has a
+         * construct signature that takes in an `initializer` function that in turn supplies
+         * a `resolve` function as one of its arguments and results in an object with a
+         * callable `then` signature.
+         *
+         * @param node The signature to check
+         */
+        function checkAsyncFunctionReturnType(node) {
+            // As part of our emit for an async function, we will need to emit the entity name of
+            // the return type annotation as an expression. To meet the necessary runtime semantics
+            // for __awaiter, we must also check that the type of the declaration (e.g. the static
+            // side or "constructor" of the promise type) is compatible `PromiseConstructorLike`.
+            //
+            // An example might be (from lib.es6.d.ts):
+            //
+            //  interface Promise<T> { ... }
+            //  interface PromiseConstructor {
+            //      new <T>(...): Promise<T>;
+            //  }
+            //  declare var Promise: PromiseConstructor;
+            //
+            // When an async function declares a return type annotation of `Promise<T>`, we
+            // need to get the type of the `Promise` variable declaration above, which would
+            // be `PromiseConstructor`.
+            //
+            // The same case applies to a class:
+            //
+            //  declare class Promise<T> {
+            //      constructor(...);
+            //      then<U>(...): Promise<U>;
+            //  }
+            //
+            var returnTypeNode = ts.getEffectiveReturnTypeNode(node); // TODO: GH#18217
+            var returnType = getTypeFromTypeNode(returnTypeNode);
+            if (languageVersion >= 2 /* ES2015 */) {
+                if (returnType === errorType) {
+                    return errorType;
+                }
+                var globalPromiseType = getGlobalPromiseType(/*reportErrors*/ true);
+                if (globalPromiseType !== emptyGenericType && !isReferenceToType(returnType, globalPromiseType)) {
+                    // The promise type was not a valid type reference to the global promise type, so we
+                    // report an error and return the unknown type.
+                    error(returnTypeNode, ts.Diagnostics.The_return_type_of_an_async_function_or_method_must_be_the_global_Promise_T_type);
+                    return errorType;
+                }
+            }
+            else {
+                // Always mark the type node as referenced if it points to a value
+                markTypeNodeAsReferenced(returnTypeNode);
+                if (returnType === errorType) {
+                    return errorType;
+                }
+                var promiseConstructorName = ts.getEntityNameFromTypeNode(returnTypeNode);
+                if (promiseConstructorName === undefined) {
+                    error(returnTypeNode, ts.Diagnostics.Type_0_is_not_a_valid_async_function_return_type_in_ES5_SlashES3_because_it_does_not_refer_to_a_Promise_compatible_constructor_value, typeToString(returnType));
+                    return errorType;
+                }
+                var promiseConstructorSymbol = resolveEntityName(promiseConstructorName, 67216319 /* Value */, /*ignoreErrors*/ true);
+                var promiseConstructorType = promiseConstructorSymbol ? getTypeOfSymbol(promiseConstructorSymbol) : errorType;
+                if (promiseConstructorType === errorType) {
+                    if (promiseConstructorName.kind === 71 /* Identifier */ && promiseConstructorName.escapedText === "Promise" && getTargetType(returnType) === getGlobalPromiseType(/*reportErrors*/ false)) {
+                        error(returnTypeNode, ts.Diagnostics.An_async_function_or_method_in_ES5_SlashES3_requires_the_Promise_constructor_Make_sure_you_have_a_declaration_for_the_Promise_constructor_or_include_ES2015_in_your_lib_option);
+                    }
+                    else {
+                        error(returnTypeNode, ts.Diagnostics.Type_0_is_not_a_valid_async_function_return_type_in_ES5_SlashES3_because_it_does_not_refer_to_a_Promise_compatible_constructor_value, ts.entityNameToString(promiseConstructorName));
+                    }
+                    return errorType;
+                }
+                var globalPromiseConstructorLikeType = getGlobalPromiseConstructorLikeType(/*reportErrors*/ true);
+                if (globalPromiseConstructorLikeType === emptyObjectType) {
+                    // If we couldn't resolve the global PromiseConstructorLike type we cannot verify
+                    // compatibility with __awaiter.
+                    error(returnTypeNode, ts.Diagnostics.Type_0_is_not_a_valid_async_function_return_type_in_ES5_SlashES3_because_it_does_not_refer_to_a_Promise_compatible_constructor_value, ts.entityNameToString(promiseConstructorName));
+                    return errorType;
+                }
+                if (!checkTypeAssignableTo(promiseConstructorType, globalPromiseConstructorLikeType, returnTypeNode, ts.Diagnostics.Type_0_is_not_a_valid_async_function_return_type_in_ES5_SlashES3_because_it_does_not_refer_to_a_Promise_compatible_constructor_value)) {
+                    return errorType;
+                }
+                // Verify there is no local declaration that could collide with the promise constructor.
+                var rootName = promiseConstructorName && getFirstIdentifier(promiseConstructorName);
+                var collidingSymbol = getSymbol(node.locals, rootName.escapedText, 67216319 /* Value */);
+                if (collidingSymbol) {
+                    error(collidingSymbol.valueDeclaration, ts.Diagnostics.Duplicate_identifier_0_Compiler_uses_declaration_1_to_support_async_functions, ts.idText(rootName), ts.entityNameToString(promiseConstructorName));
+                    return errorType;
+                }
+            }
+            // Get and return the awaited type of the return type.
+            return checkAwaitedType(returnType, node, ts.Diagnostics.The_return_type_of_an_async_function_must_either_be_a_valid_promise_or_must_not_contain_a_callable_then_member);
+        }
+        /** Check a decorator */
+        function checkDecorator(node) {
+            var signature = getResolvedSignature(node);
+            var returnType = getReturnTypeOfSignature(signature);
+            if (returnType.flags & 1 /* Any */) {
+                return;
+            }
+            var expectedReturnType;
+            var headMessage = getDiagnosticHeadMessageForDecoratorResolution(node);
+            var errorInfo;
+            switch (node.parent.kind) {
+                case 235 /* ClassDeclaration */:
+                    var classSymbol = getSymbolOfNode(node.parent);
+                    var classConstructorType = getTypeOfSymbol(classSymbol);
+                    expectedReturnType = getUnionType([classConstructorType, voidType]);
+                    break;
+                case 149 /* Parameter */:
+                    expectedReturnType = voidType;
+                    errorInfo = ts.chainDiagnosticMessages(
+                    /*details*/ undefined, ts.Diagnostics.The_return_type_of_a_parameter_decorator_function_must_be_either_void_or_any);
+                    break;
+                case 152 /* PropertyDeclaration */:
+                    expectedReturnType = voidType;
+                    errorInfo = ts.chainDiagnosticMessages(
+                    /*details*/ undefined, ts.Diagnostics.The_return_type_of_a_property_decorator_function_must_be_either_void_or_any);
+                    break;
+                case 154 /* MethodDeclaration */:
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                    var methodType = getTypeOfNode(node.parent); // TODO: GH#18217
+                    var descriptorType = createTypedPropertyDescriptorType(methodType);
+                    expectedReturnType = getUnionType([descriptorType, voidType]);
+                    break;
+                default:
+                    return ts.Debug.fail();
+            }
+            checkTypeAssignableTo(returnType, expectedReturnType, node, headMessage, function () { return errorInfo; });
+        }
+        /**
+         * If a TypeNode can be resolved to a value symbol imported from an external module, it is
+         * marked as referenced to prevent import elision.
+         */
+        function markTypeNodeAsReferenced(node) {
+            markEntityNameOrEntityExpressionAsReference(node && ts.getEntityNameFromTypeNode(node));
+        }
+        function markEntityNameOrEntityExpressionAsReference(typeName) {
+            if (!typeName)
+                return;
+            var rootName = getFirstIdentifier(typeName);
+            var meaning = (typeName.kind === 71 /* Identifier */ ? 67901928 /* Type */ : 1920 /* Namespace */) | 2097152 /* Alias */;
+            var rootSymbol = resolveName(rootName, rootName.escapedText, meaning, /*nameNotFoundMessage*/ undefined, /*nameArg*/ undefined, /*isRefernce*/ true);
+            if (rootSymbol
+                && rootSymbol.flags & 2097152 /* Alias */
+                && symbolIsValue(rootSymbol)
+                && !isConstEnumOrConstEnumOnlyModule(resolveAlias(rootSymbol))) {
+                markAliasSymbolAsReferenced(rootSymbol);
+            }
+        }
+        /**
+         * This function marks the type used for metadata decorator as referenced if it is import
+         * from external module.
+         * This is different from markTypeNodeAsReferenced because it tries to simplify type nodes in
+         * union and intersection type
+         * @param node
+         */
+        function markDecoratorMedataDataTypeNodeAsReferenced(node) {
+            var entityName = getEntityNameForDecoratorMetadata(node);
+            if (entityName && ts.isEntityName(entityName)) {
+                markEntityNameOrEntityExpressionAsReference(entityName);
+            }
+        }
+        function getEntityNameForDecoratorMetadata(node) {
+            if (node) {
+                switch (node.kind) {
+                    case 170 /* IntersectionType */:
+                    case 169 /* UnionType */:
+                        var commonEntityName = void 0;
+                        for (var _i = 0, _a = node.types; _i < _a.length; _i++) {
+                            var typeNode = _a[_i];
+                            while (typeNode.kind === 173 /* ParenthesizedType */) {
+                                typeNode = typeNode.type; // Skip parens if need be
+                            }
+                            if (typeNode.kind === 131 /* NeverKeyword */) {
+                                continue; // Always elide `never` from the union/intersection if possible
+                            }
+                            if (!strictNullChecks && (typeNode.kind === 95 /* NullKeyword */ || typeNode.kind === 140 /* UndefinedKeyword */)) {
+                                continue; // Elide null and undefined from unions for metadata, just like what we did prior to the implementation of strict null checks
+                            }
+                            var individualEntityName = getEntityNameForDecoratorMetadata(typeNode);
+                            if (!individualEntityName) {
+                                // Individual is something like string number
+                                // So it would be serialized to either that type or object
+                                // Safe to return here
+                                return undefined;
+                            }
+                            if (commonEntityName) {
+                                // Note this is in sync with the transformation that happens for type node.
+                                // Keep this in sync with serializeUnionOrIntersectionType
+                                // Verify if they refer to same entity and is identifier
+                                // return undefined if they dont match because we would emit object
+                                if (!ts.isIdentifier(commonEntityName) ||
+                                    !ts.isIdentifier(individualEntityName) ||
+                                    commonEntityName.escapedText !== individualEntityName.escapedText) {
+                                    return undefined;
+                                }
+                            }
+                            else {
+                                commonEntityName = individualEntityName;
+                            }
+                        }
+                        return commonEntityName;
+                    case 173 /* ParenthesizedType */:
+                        return getEntityNameForDecoratorMetadata(node.type);
+                    case 162 /* TypeReference */:
+                        return node.typeName;
+                }
+            }
+        }
+        function getParameterTypeNodeForDecoratorCheck(node) {
+            var typeNode = ts.getEffectiveTypeAnnotationNode(node);
+            return ts.isRestParameter(node) ? ts.getRestParameterElementType(typeNode) : typeNode;
+        }
+        /** Check the decorators of a node */
+        function checkDecorators(node) {
+            if (!node.decorators) {
+                return;
+            }
+            // skip this check for nodes that cannot have decorators. These should have already had an error reported by
+            // checkGrammarDecorators.
+            if (!ts.nodeCanBeDecorated(node, node.parent, node.parent.parent)) {
+                return;
+            }
+            if (!compilerOptions.experimentalDecorators) {
+                error(node, ts.Diagnostics.Experimental_support_for_decorators_is_a_feature_that_is_subject_to_change_in_a_future_release_Set_the_experimentalDecorators_option_to_remove_this_warning);
+            }
+            var firstDecorator = node.decorators[0];
+            checkExternalEmitHelpers(firstDecorator, 8 /* Decorate */);
+            if (node.kind === 149 /* Parameter */) {
+                checkExternalEmitHelpers(firstDecorator, 32 /* Param */);
+            }
+            if (compilerOptions.emitDecoratorMetadata) {
+                checkExternalEmitHelpers(firstDecorator, 16 /* Metadata */);
+                // we only need to perform these checks if we are emitting serialized type metadata for the target of a decorator.
+                switch (node.kind) {
+                    case 235 /* ClassDeclaration */:
+                        var constructor = ts.getFirstConstructorWithBody(node);
+                        if (constructor) {
+                            for (var _i = 0, _a = constructor.parameters; _i < _a.length; _i++) {
+                                var parameter = _a[_i];
+                                markDecoratorMedataDataTypeNodeAsReferenced(getParameterTypeNodeForDecoratorCheck(parameter));
+                            }
+                        }
+                        break;
+                    case 154 /* MethodDeclaration */:
+                    case 156 /* GetAccessor */:
+                    case 157 /* SetAccessor */:
+                        for (var _b = 0, _c = node.parameters; _b < _c.length; _b++) {
+                            var parameter = _c[_b];
+                            markDecoratorMedataDataTypeNodeAsReferenced(getParameterTypeNodeForDecoratorCheck(parameter));
+                        }
+                        markDecoratorMedataDataTypeNodeAsReferenced(ts.getEffectiveReturnTypeNode(node));
+                        break;
+                    case 152 /* PropertyDeclaration */:
+                        markDecoratorMedataDataTypeNodeAsReferenced(ts.getEffectiveTypeAnnotationNode(node));
+                        break;
+                    case 149 /* Parameter */:
+                        markDecoratorMedataDataTypeNodeAsReferenced(getParameterTypeNodeForDecoratorCheck(node));
+                        var containingSignature = node.parent;
+                        for (var _d = 0, _e = containingSignature.parameters; _d < _e.length; _d++) {
+                            var parameter = _e[_d];
+                            markDecoratorMedataDataTypeNodeAsReferenced(getParameterTypeNodeForDecoratorCheck(parameter));
+                        }
+                        break;
+                }
+            }
+            ts.forEach(node.decorators, checkDecorator);
+        }
+        function checkFunctionDeclaration(node) {
+            if (produceDiagnostics) {
+                checkFunctionOrMethodDeclaration(node);
+                checkGrammarForGenerator(node);
+                checkCollisionWithRequireExportsInGeneratedCode(node, node.name);
+                checkCollisionWithGlobalPromiseInGeneratedCode(node, node.name);
+            }
+        }
+        function checkJSDocTypeAliasTag(node) {
+            if (!node.typeExpression) {
+                // If the node had `@property` tags, `typeExpression` would have been set to the first property tag.
+                error(node.name, ts.Diagnostics.JSDoc_typedef_tag_should_either_have_a_type_annotation_or_be_followed_by_property_or_member_tags);
+            }
+            if (node.name) {
+                checkTypeNameIsReserved(node.name, ts.Diagnostics.Type_alias_name_cannot_be_0);
+            }
+            checkSourceElement(node.typeExpression);
+        }
+        function checkJSDocParameterTag(node) {
+            checkSourceElement(node.typeExpression);
+            if (!ts.getParameterSymbolFromJSDoc(node)) {
+                var decl = ts.getHostSignatureFromJSDoc(node);
+                // don't issue an error for invalid hosts -- just functions --
+                // and give a better error message when the host function mentions `arguments`
+                // but the tag doesn't have an array type
+                if (decl) {
+                    var i = ts.getJSDocTags(decl).filter(ts.isJSDocParameterTag).indexOf(node);
+                    if (i > -1 && i < decl.parameters.length && ts.isBindingPattern(decl.parameters[i].name)) {
+                        return;
+                    }
+                    if (!containsArgumentsReference(decl)) {
+                        error(node.name, ts.Diagnostics.JSDoc_param_tag_has_name_0_but_there_is_no_parameter_with_that_name, ts.idText(node.name.kind === 146 /* QualifiedName */ ? node.name.right : node.name));
+                    }
+                    else if (ts.findLast(ts.getJSDocTags(decl), ts.isJSDocParameterTag) === node &&
+                        node.typeExpression && node.typeExpression.type &&
+                        !isArrayType(getTypeFromTypeNode(node.typeExpression.type))) {
+                        error(node.name, ts.Diagnostics.JSDoc_param_tag_has_name_0_but_there_is_no_parameter_with_that_name_It_would_match_arguments_if_it_had_an_array_type, ts.idText(node.name.kind === 146 /* QualifiedName */ ? node.name.right : node.name));
+                    }
+                }
+            }
+        }
+        function checkJSDocAugmentsTag(node) {
+            var classLike = ts.getJSDocHost(node);
+            if (!ts.isClassDeclaration(classLike) && !ts.isClassExpression(classLike)) {
+                error(classLike, ts.Diagnostics.JSDoc_0_is_not_attached_to_a_class, ts.idText(node.tagName));
+                return;
+            }
+            var augmentsTags = ts.getJSDocTags(classLike).filter(ts.isJSDocAugmentsTag);
+            ts.Debug.assert(augmentsTags.length > 0);
+            if (augmentsTags.length > 1) {
+                error(augmentsTags[1], ts.Diagnostics.Class_declarations_cannot_have_more_than_one_augments_or_extends_tag);
+            }
+            var name = getIdentifierFromEntityNameExpression(node.class.expression);
+            var extend = ts.getClassExtendsHeritageClauseElement(classLike);
+            if (extend) {
+                var className = getIdentifierFromEntityNameExpression(extend.expression);
+                if (className && name.escapedText !== className.escapedText) {
+                    error(name, ts.Diagnostics.JSDoc_0_1_does_not_match_the_extends_2_clause, ts.idText(node.tagName), ts.idText(name), ts.idText(className));
+                }
+            }
+        }
+        function getIdentifierFromEntityNameExpression(node) {
+            switch (node.kind) {
+                case 71 /* Identifier */:
+                    return node;
+                case 185 /* PropertyAccessExpression */:
+                    return node.name;
+                default:
+                    return undefined;
+            }
+        }
+        function checkFunctionOrMethodDeclaration(node) {
+            checkDecorators(node);
+            checkSignatureDeclaration(node);
+            var functionFlags = ts.getFunctionFlags(node);
+            // Do not use hasDynamicName here, because that returns false for well known symbols.
+            // We want to perform checkComputedPropertyName for all computed properties, including
+            // well known symbols.
+            if (node.name && node.name.kind === 147 /* ComputedPropertyName */) {
+                // This check will account for methods in class/interface declarations,
+                // as well as accessors in classes/object literals
+                checkComputedPropertyName(node.name);
+            }
+            if (!hasNonBindableDynamicName(node)) {
+                // first we want to check the local symbol that contain this declaration
+                // - if node.localSymbol !== undefined - this is current declaration is exported and localSymbol points to the local symbol
+                // - if node.localSymbol === undefined - this node is non-exported so we can just pick the result of getSymbolOfNode
+                var symbol = getSymbolOfNode(node);
+                var localSymbol = node.localSymbol || symbol;
+                // Since the javascript won't do semantic analysis like typescript,
+                // if the javascript file comes before the typescript file and both contain same name functions,
+                // checkFunctionOrConstructorSymbol wouldn't be called if we didnt ignore javascript function.
+                var firstDeclaration = ts.find(localSymbol.declarations, 
+                // Get first non javascript function declaration
+                function (declaration) { return declaration.kind === node.kind && !(declaration.flags & 65536 /* JavaScriptFile */); });
+                // Only type check the symbol once
+                if (node === firstDeclaration) {
+                    checkFunctionOrConstructorSymbol(localSymbol);
+                }
+                if (symbol.parent) {
+                    // run check once for the first declaration
+                    if (ts.getDeclarationOfKind(symbol, node.kind) === node) {
+                        // run check on export symbol to check that modifiers agree across all exported declarations
+                        checkFunctionOrConstructorSymbol(symbol);
+                    }
+                }
+            }
+            var body = node.kind === 153 /* MethodSignature */ ? undefined : node.body;
+            checkSourceElement(body);
+            var returnTypeNode = ts.getEffectiveReturnTypeNode(node);
+            if ((functionFlags & 1 /* Generator */) === 0) { // Async function or normal function
+                var returnOrPromisedType = returnTypeNode && (functionFlags & 2 /* Async */
+                    ? checkAsyncFunctionReturnType(node) // Async function
+                    : getTypeFromTypeNode(returnTypeNode)); // normal function
+                checkAllCodePathsInNonVoidFunctionReturnOrThrow(node, returnOrPromisedType);
+            }
+            if (produceDiagnostics && !returnTypeNode) {
+                // Report an implicit any error if there is no body, no explicit return type, and node is not a private method
+                // in an ambient context
+                if (noImplicitAny && ts.nodeIsMissing(body) && !isPrivateWithinAmbient(node)) {
+                    reportImplicitAnyError(node, anyType);
+                }
+                if (functionFlags & 1 /* Generator */ && ts.nodeIsPresent(body)) {
+                    // A generator with a body and no type annotation can still cause errors. It can error if the
+                    // yielded values have no common supertype, or it can give an implicit any error if it has no
+                    // yielded values. The only way to trigger these errors is to try checking its return type.
+                    getReturnTypeOfSignature(getSignatureFromDeclaration(node));
+                }
+            }
+        }
+        function registerForUnusedIdentifiersCheck(node) {
+            // May be in a call such as getTypeOfNode that happened to call this. But potentiallyUnusedIdentifiers is only defined in the scope of `checkSourceFile`.
+            if (produceDiagnostics) {
+                var sourceFile = ts.getSourceFileOfNode(node);
+                var potentiallyUnusedIdentifiers = allPotentiallyUnusedIdentifiers.get(sourceFile.path);
+                if (!potentiallyUnusedIdentifiers) {
+                    potentiallyUnusedIdentifiers = [];
+                    allPotentiallyUnusedIdentifiers.set(sourceFile.path, potentiallyUnusedIdentifiers);
+                }
+                // TODO: GH#22580
+                // Debug.assert(addToSeen(seenPotentiallyUnusedIdentifiers, getNodeId(node)), "Adding potentially-unused identifier twice");
+                potentiallyUnusedIdentifiers.push(node);
+            }
+        }
+        function checkUnusedIdentifiers(potentiallyUnusedIdentifiers, addDiagnostic) {
+            for (var _i = 0, potentiallyUnusedIdentifiers_1 = potentiallyUnusedIdentifiers; _i < potentiallyUnusedIdentifiers_1.length; _i++) {
+                var node = potentiallyUnusedIdentifiers_1[_i];
+                switch (node.kind) {
+                    case 235 /* ClassDeclaration */:
+                    case 205 /* ClassExpression */:
+                        checkUnusedClassMembers(node, addDiagnostic);
+                        checkUnusedTypeParameters(node, addDiagnostic);
+                        break;
+                    case 236 /* InterfaceDeclaration */:
+                        checkUnusedTypeParameters(node, addDiagnostic);
+                        break;
+                    case 274 /* SourceFile */:
+                    case 239 /* ModuleDeclaration */:
+                    case 213 /* Block */:
+                    case 241 /* CaseBlock */:
+                    case 220 /* ForStatement */:
+                    case 221 /* ForInStatement */:
+                    case 222 /* ForOfStatement */:
+                        checkUnusedLocalsAndParameters(node, addDiagnostic);
+                        break;
+                    case 155 /* Constructor */:
+                    case 192 /* FunctionExpression */:
+                    case 234 /* FunctionDeclaration */:
+                    case 193 /* ArrowFunction */:
+                    case 154 /* MethodDeclaration */:
+                    case 156 /* GetAccessor */:
+                    case 157 /* SetAccessor */:
+                        if (node.body) {
+                            checkUnusedLocalsAndParameters(node, addDiagnostic);
+                        }
+                        checkUnusedTypeParameters(node, addDiagnostic);
+                        break;
+                    case 153 /* MethodSignature */:
+                    case 158 /* CallSignature */:
+                    case 159 /* ConstructSignature */:
+                    case 163 /* FunctionType */:
+                    case 164 /* ConstructorType */:
+                    case 237 /* TypeAliasDeclaration */:
+                        checkUnusedTypeParameters(node, addDiagnostic);
+                        break;
+                    default:
+                        ts.Debug.assertNever(node, "Node should not have been registered for unused identifiers check");
+                }
+            }
+        }
+        function errorUnusedLocal(declaration, name, addDiagnostic) {
+            var node = ts.getNameOfDeclaration(declaration) || declaration;
+            var message = isTypeDeclaration(declaration) ? ts.Diagnostics._0_is_declared_but_never_used : ts.Diagnostics._0_is_declared_but_its_value_is_never_read;
+            addDiagnostic(0 /* Local */, ts.createDiagnosticForNode(node, message, name));
+        }
+        function parameterNameStartsWithUnderscore(parameterName) {
+            return parameterName && isIdentifierThatStartsWithUnderScore(parameterName);
+        }
+        function isIdentifierThatStartsWithUnderScore(node) {
+            return ts.isIdentifier(node) && ts.idText(node).charCodeAt(0) === 95 /* _ */;
+        }
+        function checkUnusedClassMembers(node, addDiagnostic) {
+            if (!(node.flags & 4194304 /* Ambient */)) {
+                for (var _i = 0, _a = node.members; _i < _a.length; _i++) {
+                    var member = _a[_i];
+                    switch (member.kind) {
+                        case 154 /* MethodDeclaration */:
+                        case 152 /* PropertyDeclaration */:
+                        case 156 /* GetAccessor */:
+                        case 157 /* SetAccessor */:
+                            if (member.kind === 157 /* SetAccessor */ && member.symbol.flags & 32768 /* GetAccessor */) {
+                                // Already would have reported an error on the getter.
+                                break;
+                            }
+                            var symbol = getSymbolOfNode(member);
+                            if (!symbol.isReferenced && ts.hasModifier(member, 8 /* Private */)) {
+                                addDiagnostic(0 /* Local */, ts.createDiagnosticForNode(member.name, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, symbolToString(symbol)));
+                            }
+                            break;
+                        case 155 /* Constructor */:
+                            for (var _b = 0, _c = member.parameters; _b < _c.length; _b++) {
+                                var parameter = _c[_b];
+                                if (!parameter.symbol.isReferenced && ts.hasModifier(parameter, 8 /* Private */)) {
+                                    addDiagnostic(0 /* Local */, ts.createDiagnosticForNode(parameter.name, ts.Diagnostics.Property_0_is_declared_but_its_value_is_never_read, ts.symbolName(parameter.symbol)));
+                                }
+                            }
+                            break;
+                        case 160 /* IndexSignature */:
+                        case 212 /* SemicolonClassElement */:
+                            // Can't be private
+                            break;
+                        default:
+                            ts.Debug.fail();
+                    }
+                }
+            }
+        }
+        function checkUnusedTypeParameters(node, addDiagnostic) {
+            // Only report errors on the last declaration for the type parameter container;
+            // this ensures that all uses have been accounted for.
+            var typeParameters = ts.getEffectiveTypeParameterDeclarations(node);
+            if (!(node.flags & 4194304 /* Ambient */) && ts.last(getSymbolOfNode(node).declarations) === node) {
+                for (var _i = 0, typeParameters_2 = typeParameters; _i < typeParameters_2.length; _i++) {
+                    var typeParameter = typeParameters_2[_i];
+                    if (!(getMergedSymbol(typeParameter.symbol).isReferenced & 262144 /* TypeParameter */) && !isIdentifierThatStartsWithUnderScore(typeParameter.name)) {
+                        addDiagnostic(1 /* Parameter */, ts.createDiagnosticForNode(typeParameter.name, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, ts.symbolName(typeParameter.symbol)));
+                    }
+                }
+            }
+        }
+        function addToGroup(map, key, value, getKey) {
+            var keyString = String(getKey(key));
+            var group = map.get(keyString);
+            if (group) {
+                group[1].push(value);
+            }
+            else {
+                map.set(keyString, [key, [value]]);
+            }
+        }
+        function tryGetRootParameterDeclaration(node) {
+            return ts.tryCast(ts.getRootDeclaration(node), ts.isParameter);
+        }
+        function checkUnusedLocalsAndParameters(nodeWithLocals, addDiagnostic) {
+            if (nodeWithLocals.flags & 4194304 /* Ambient */)
+                return;
+            // Ideally we could use the ImportClause directly as a key, but must wait until we have full ES6 maps. So must store key along with value.
+            var unusedImports = ts.createMap();
+            var unusedDestructures = ts.createMap();
+            var unusedVariables = ts.createMap();
+            nodeWithLocals.locals.forEach(function (local) {
+                // If it's purely a type parameter, ignore, will be checked in `checkUnusedTypeParameters`.
+                // If it's a type parameter merged with a parameter, check if the parameter-side is used.
+                if (local.flags & 262144 /* TypeParameter */ ? !(local.flags & 3 /* Variable */ && !(local.isReferenced & 3 /* Variable */)) : local.isReferenced || local.exportSymbol) {
+                    return;
+                }
+                for (var _i = 0, _a = local.declarations; _i < _a.length; _i++) {
+                    var declaration = _a[_i];
+                    if (ts.isAmbientModule(declaration))
+                        continue;
+                    if (isImportedDeclaration(declaration)) {
+                        addToGroup(unusedImports, importClauseFromImported(declaration), declaration, getNodeId);
+                    }
+                    else if (ts.isBindingElement(declaration) && ts.isObjectBindingPattern(declaration.parent)) {
+                        // In `{ a, ...b }, `a` is considered used since it removes a property from `b`. `b` may still be unused though.
+                        var lastElement = ts.last(declaration.parent.elements);
+                        if (declaration === lastElement || !ts.last(declaration.parent.elements).dotDotDotToken) {
+                            addToGroup(unusedDestructures, declaration.parent, declaration, getNodeId);
+                        }
+                    }
+                    else if (ts.isVariableDeclaration(declaration)) {
+                        if (!isIdentifierThatStartsWithUnderScore(declaration.name) || !ts.isForInOrOfStatement(declaration.parent.parent)) {
+                            addToGroup(unusedVariables, declaration.parent, declaration, getNodeId);
+                        }
+                    }
+                    else {
+                        var parameter = local.valueDeclaration && tryGetRootParameterDeclaration(local.valueDeclaration);
+                        if (parameter) {
+                            var name = ts.getNameOfDeclaration(local.valueDeclaration);
+                            if (!ts.isParameterPropertyDeclaration(parameter) && !ts.parameterIsThisKeyword(parameter) && !parameterNameStartsWithUnderscore(name)) {
+                                addDiagnostic(1 /* Parameter */, ts.createDiagnosticForNode(name, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, ts.symbolName(local)));
+                            }
+                        }
+                        else {
+                            errorUnusedLocal(declaration, ts.symbolName(local), addDiagnostic);
+                        }
+                    }
+                }
+            });
+            unusedImports.forEach(function (_a) {
+                var importClause = _a[0], unuseds = _a[1];
+                var importDecl = importClause.parent;
+                var nDeclarations = (importClause.name ? 1 : 0) +
+                    (importClause.namedBindings ?
+                        (importClause.namedBindings.kind === 246 /* NamespaceImport */ ? 1 : importClause.namedBindings.elements.length)
+                        : 0);
+                if (nDeclarations === unuseds.length) {
+                    addDiagnostic(0 /* Local */, unuseds.length === 1
+                        ? ts.createDiagnosticForNode(importDecl, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, ts.idText(ts.first(unuseds).name))
+                        : ts.createDiagnosticForNode(importDecl, ts.Diagnostics.All_imports_in_import_declaration_are_unused));
+                }
+                else {
+                    for (var _i = 0, unuseds_1 = unuseds; _i < unuseds_1.length; _i++) {
+                        var unused = unuseds_1[_i];
+                        errorUnusedLocal(unused, ts.idText(unused.name), addDiagnostic);
+                    }
+                }
+            });
+            unusedDestructures.forEach(function (_a) {
+                var bindingPattern = _a[0], bindingElements = _a[1];
+                var kind = tryGetRootParameterDeclaration(bindingPattern.parent) ? 1 /* Parameter */ : 0 /* Local */;
+                if (bindingPattern.elements.length === bindingElements.length) {
+                    if (bindingElements.length === 1 && bindingPattern.parent.kind === 232 /* VariableDeclaration */ && bindingPattern.parent.parent.kind === 233 /* VariableDeclarationList */) {
+                        addToGroup(unusedVariables, bindingPattern.parent.parent, bindingPattern.parent, getNodeId);
+                    }
+                    else {
+                        addDiagnostic(kind, bindingElements.length === 1
+                            ? ts.createDiagnosticForNode(bindingPattern, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, ts.idText(ts.cast(ts.first(bindingElements).name, ts.isIdentifier)))
+                            : ts.createDiagnosticForNode(bindingPattern, ts.Diagnostics.All_destructured_elements_are_unused));
+                    }
+                }
+                else {
+                    for (var _i = 0, bindingElements_1 = bindingElements; _i < bindingElements_1.length; _i++) {
+                        var e = bindingElements_1[_i];
+                        addDiagnostic(kind, ts.createDiagnosticForNode(e, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, ts.idText(ts.cast(e.name, ts.isIdentifier))));
+                    }
+                }
+            });
+            unusedVariables.forEach(function (_a) {
+                var declarationList = _a[0], declarations = _a[1];
+                if (declarationList.declarations.length === declarations.length) {
+                    addDiagnostic(0 /* Local */, declarations.length === 1
+                        ? ts.createDiagnosticForNode(ts.first(declarations).name, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, bindingNameText(ts.first(declarations).name))
+                        : ts.createDiagnosticForNode(declarationList.parent.kind === 214 /* VariableStatement */ ? declarationList.parent : declarationList, ts.Diagnostics.All_variables_are_unused));
+                }
+                else {
+                    for (var _i = 0, declarations_5 = declarations; _i < declarations_5.length; _i++) {
+                        var decl = declarations_5[_i];
+                        addDiagnostic(0 /* Local */, ts.createDiagnosticForNode(decl, ts.Diagnostics._0_is_declared_but_its_value_is_never_read, ts.idText(ts.cast(decl.name, ts.isIdentifier))));
+                    }
+                }
+            });
+        }
+        function bindingNameText(name) {
+            switch (name.kind) {
+                case 71 /* Identifier */:
+                    return ts.idText(name);
+                case 181 /* ArrayBindingPattern */:
+                case 180 /* ObjectBindingPattern */:
+                    return bindingNameText(ts.cast(ts.first(name.elements), ts.isBindingElement).name);
+                default:
+                    return ts.Debug.assertNever(name);
+            }
+        }
+        function isImportedDeclaration(node) {
+            return node.kind === 245 /* ImportClause */ || node.kind === 248 /* ImportSpecifier */ || node.kind === 246 /* NamespaceImport */;
+        }
+        function importClauseFromImported(decl) {
+            return decl.kind === 245 /* ImportClause */ ? decl : decl.kind === 246 /* NamespaceImport */ ? decl.parent : decl.parent.parent;
+        }
+        function checkBlock(node) {
+            // Grammar checking for SyntaxKind.Block
+            if (node.kind === 213 /* Block */) {
+                checkGrammarStatementInAmbientContext(node);
+            }
+            if (ts.isFunctionOrModuleBlock(node)) {
+                var saveFlowAnalysisDisabled = flowAnalysisDisabled;
+                ts.forEach(node.statements, checkSourceElement);
+                flowAnalysisDisabled = saveFlowAnalysisDisabled;
+            }
+            else {
+                ts.forEach(node.statements, checkSourceElement);
+            }
+            if (node.locals) {
+                registerForUnusedIdentifiersCheck(node);
+            }
+        }
+        function checkCollisionWithArgumentsInGeneratedCode(node) {
+            // no rest parameters \ declaration context \ overload - no codegen impact
+            if (languageVersion >= 2 /* ES2015 */ || compilerOptions.noEmit || !ts.hasRestParameter(node) || node.flags & 4194304 /* Ambient */ || ts.nodeIsMissing(node.body)) {
+                return;
+            }
+            ts.forEach(node.parameters, function (p) {
+                if (p.name && !ts.isBindingPattern(p.name) && p.name.escapedText === argumentsSymbol.escapedName) {
+                    error(p, ts.Diagnostics.Duplicate_identifier_arguments_Compiler_uses_arguments_to_initialize_rest_parameters);
+                }
+            });
+        }
+        function needCollisionCheckForIdentifier(node, identifier, name) {
+            if (!(identifier && identifier.escapedText === name)) {
+                return false;
+            }
+            if (node.kind === 152 /* PropertyDeclaration */ ||
+                node.kind === 151 /* PropertySignature */ ||
+                node.kind === 154 /* MethodDeclaration */ ||
+                node.kind === 153 /* MethodSignature */ ||
+                node.kind === 156 /* GetAccessor */ ||
+                node.kind === 157 /* SetAccessor */) {
+                // it is ok to have member named '_super' or '_this' - member access is always qualified
+                return false;
+            }
+            if (node.flags & 4194304 /* Ambient */) {
+                // ambient context - no codegen impact
+                return false;
+            }
+            var root = ts.getRootDeclaration(node);
+            if (root.kind === 149 /* Parameter */ && ts.nodeIsMissing(root.parent.body)) {
+                // just an overload - no codegen impact
+                return false;
+            }
+            return true;
+        }
+        // this function will run after checking the source file so 'CaptureThis' is correct for all nodes
+        function checkIfThisIsCapturedInEnclosingScope(node) {
+            ts.findAncestor(node, function (current) {
+                if (getNodeCheckFlags(current) & 4 /* CaptureThis */) {
+                    var isDeclaration_1 = node.kind !== 71 /* Identifier */;
+                    if (isDeclaration_1) {
+                        error(ts.getNameOfDeclaration(node), ts.Diagnostics.Duplicate_identifier_this_Compiler_uses_variable_declaration_this_to_capture_this_reference);
+                    }
+                    else {
+                        error(node, ts.Diagnostics.Expression_resolves_to_variable_declaration_this_that_compiler_uses_to_capture_this_reference);
+                    }
+                    return true;
+                }
+                return false;
+            });
+        }
+        function checkIfNewTargetIsCapturedInEnclosingScope(node) {
+            ts.findAncestor(node, function (current) {
+                if (getNodeCheckFlags(current) & 8 /* CaptureNewTarget */) {
+                    var isDeclaration_2 = node.kind !== 71 /* Identifier */;
+                    if (isDeclaration_2) {
+                        error(ts.getNameOfDeclaration(node), ts.Diagnostics.Duplicate_identifier_newTarget_Compiler_uses_variable_declaration_newTarget_to_capture_new_target_meta_property_reference);
+                    }
+                    else {
+                        error(node, ts.Diagnostics.Expression_resolves_to_variable_declaration_newTarget_that_compiler_uses_to_capture_new_target_meta_property_reference);
+                    }
+                    return true;
+                }
+                return false;
+            });
+        }
+        function checkCollisionWithRequireExportsInGeneratedCode(node, name) {
+            // No need to check for require or exports for ES6 modules and later
+            if (moduleKind >= ts.ModuleKind.ES2015 || compilerOptions.noEmit) {
+                return;
+            }
+            if (!needCollisionCheckForIdentifier(node, name, "require") && !needCollisionCheckForIdentifier(node, name, "exports")) {
+                return;
+            }
+            // Uninstantiated modules shouldnt do this check
+            if (ts.isModuleDeclaration(node) && ts.getModuleInstanceState(node) !== 1 /* Instantiated */) {
+                return;
+            }
+            // In case of variable declaration, node.parent is variable statement so look at the variable statement's parent
+            var parent = getDeclarationContainer(node);
+            if (parent.kind === 274 /* SourceFile */ && ts.isExternalOrCommonJsModule(parent)) {
+                // If the declaration happens to be in external module, report error that require and exports are reserved keywords
+                error(name, ts.Diagnostics.Duplicate_identifier_0_Compiler_reserves_name_1_in_top_level_scope_of_a_module, ts.declarationNameToString(name), ts.declarationNameToString(name));
+            }
+        }
+        function checkCollisionWithGlobalPromiseInGeneratedCode(node, name) {
+            if (languageVersion >= 4 /* ES2017 */ || compilerOptions.noEmit || !needCollisionCheckForIdentifier(node, name, "Promise")) {
+                return;
+            }
+            // Uninstantiated modules shouldnt do this check
+            if (ts.isModuleDeclaration(node) && ts.getModuleInstanceState(node) !== 1 /* Instantiated */) {
+                return;
+            }
+            // In case of variable declaration, node.parent is variable statement so look at the variable statement's parent
+            var parent = getDeclarationContainer(node);
+            if (parent.kind === 274 /* SourceFile */ && ts.isExternalOrCommonJsModule(parent) && parent.flags & 1024 /* HasAsyncFunctions */) {
+                // If the declaration happens to be in external module, report error that Promise is a reserved identifier.
+                error(name, ts.Diagnostics.Duplicate_identifier_0_Compiler_reserves_name_1_in_top_level_scope_of_a_module_containing_async_functions, ts.declarationNameToString(name), ts.declarationNameToString(name));
+            }
+        }
+        function checkVarDeclaredNamesNotShadowed(node) {
+            // - ScriptBody : StatementList
+            // It is a Syntax Error if any element of the LexicallyDeclaredNames of StatementList
+            // also occurs in the VarDeclaredNames of StatementList.
+            // - Block : { StatementList }
+            // It is a Syntax Error if any element of the LexicallyDeclaredNames of StatementList
+            // also occurs in the VarDeclaredNames of StatementList.
+            // Variable declarations are hoisted to the top of their function scope. They can shadow
+            // block scoped declarations, which bind tighter. this will not be flagged as duplicate definition
+            // by the binder as the declaration scope is different.
+            // A non-initialized declaration is a no-op as the block declaration will resolve before the var
+            // declaration. the problem is if the declaration has an initializer. this will act as a write to the
+            // block declared value. this is fine for let, but not const.
+            // Only consider declarations with initializers, uninitialized const declarations will not
+            // step on a let/const variable.
+            // Do not consider const and const declarations, as duplicate block-scoped declarations
+            // are handled by the binder.
+            // We are only looking for const declarations that step on let\const declarations from a
+            // different scope. e.g.:
+            //      {
+            //          const x = 0; // localDeclarationSymbol obtained after name resolution will correspond to this declaration
+            //          const x = 0; // symbol for this declaration will be 'symbol'
+            //      }
+            // skip block-scoped variables and parameters
+            if ((ts.getCombinedNodeFlags(node) & 3 /* BlockScoped */) !== 0 || ts.isParameterDeclaration(node)) {
+                return;
+            }
+            // skip variable declarations that don't have initializers
+            // NOTE: in ES6 spec initializer is required in variable declarations where name is binding pattern
+            // so we'll always treat binding elements as initialized
+            if (node.kind === 232 /* VariableDeclaration */ && !node.initializer) {
+                return;
+            }
+            var symbol = getSymbolOfNode(node);
+            if (symbol.flags & 1 /* FunctionScopedVariable */) {
+                if (!ts.isIdentifier(node.name))
+                    return ts.Debug.fail();
+                var localDeclarationSymbol = resolveName(node, node.name.escapedText, 3 /* Variable */, /*nodeNotFoundErrorMessage*/ undefined, /*nameArg*/ undefined, /*isUse*/ false);
+                if (localDeclarationSymbol &&
+                    localDeclarationSymbol !== symbol &&
+                    localDeclarationSymbol.flags & 2 /* BlockScopedVariable */) {
+                    if (getDeclarationNodeFlagsFromSymbol(localDeclarationSymbol) & 3 /* BlockScoped */) {
+                        var varDeclList = ts.getAncestor(localDeclarationSymbol.valueDeclaration, 233 /* VariableDeclarationList */);
+                        var container = varDeclList.parent.kind === 214 /* VariableStatement */ && varDeclList.parent.parent
+                            ? varDeclList.parent.parent
+                            : undefined;
+                        // names of block-scoped and function scoped variables can collide only
+                        // if block scoped variable is defined in the function\module\source file scope (because of variable hoisting)
+                        var namesShareScope = container &&
+                            (container.kind === 213 /* Block */ && ts.isFunctionLike(container.parent) ||
+                                container.kind === 240 /* ModuleBlock */ ||
+                                container.kind === 239 /* ModuleDeclaration */ ||
+                                container.kind === 274 /* SourceFile */);
+                        // here we know that function scoped variable is shadowed by block scoped one
+                        // if they are defined in the same scope - binder has already reported redeclaration error
+                        // otherwise if variable has an initializer - show error that initialization will fail
+                        // since LHS will be block scoped name instead of function scoped
+                        if (!namesShareScope) {
+                            var name = symbolToString(localDeclarationSymbol);
+                            error(node, ts.Diagnostics.Cannot_initialize_outer_scoped_variable_0_in_the_same_scope_as_block_scoped_declaration_1, name, name);
+                        }
+                    }
+                }
+            }
+        }
+        // Check that a parameter initializer contains no references to parameters declared to the right of itself
+        function checkParameterInitializer(node) {
+            if (ts.getRootDeclaration(node).kind !== 149 /* Parameter */) {
+                return;
+            }
+            var func = ts.getContainingFunction(node);
+            visit(node.initializer);
+            function visit(n) {
+                if (ts.isTypeNode(n) || ts.isDeclarationName(n)) {
+                    // do not dive in types
+                    // skip declaration names (i.e. in object literal expressions)
+                    return;
+                }
+                if (n.kind === 185 /* PropertyAccessExpression */) {
+                    // skip property names in property access expression
+                    return visit(n.expression);
+                }
+                else if (n.kind === 71 /* Identifier */) {
+                    // check FunctionLikeDeclaration.locals (stores parameters\function local variable)
+                    // if it contains entry with a specified name
+                    var symbol = resolveName(n, n.escapedText, 67216319 /* Value */ | 2097152 /* Alias */, /*nameNotFoundMessage*/ undefined, /*nameArg*/ undefined, /*isUse*/ false);
+                    if (!symbol || symbol === unknownSymbol || !symbol.valueDeclaration) {
+                        return;
+                    }
+                    if (symbol.valueDeclaration === node) {
+                        error(n, ts.Diagnostics.Parameter_0_cannot_be_referenced_in_its_initializer, ts.declarationNameToString(node.name));
+                        return;
+                    }
+                    // locals map for function contain both parameters and function locals
+                    // so we need to do a bit of extra work to check if reference is legal
+                    var enclosingContainer = ts.getEnclosingBlockScopeContainer(symbol.valueDeclaration);
+                    if (enclosingContainer === func) {
+                        if (symbol.valueDeclaration.kind === 149 /* Parameter */ ||
+                            symbol.valueDeclaration.kind === 182 /* BindingElement */) {
+                            // it is ok to reference parameter in initializer if either
+                            // - parameter is located strictly on the left of current parameter declaration
+                            if (symbol.valueDeclaration.pos < node.pos) {
+                                return;
+                            }
+                            // - parameter is wrapped in function-like entity
+                            if (ts.findAncestor(n, function (current) {
+                                if (current === node.initializer) {
+                                    return "quit";
+                                }
+                                return ts.isFunctionLike(current.parent) ||
+                                    // computed property names/initializers in instance property declaration of class like entities
+                                    // are executed in constructor and thus deferred
+                                    (current.parent.kind === 152 /* PropertyDeclaration */ &&
+                                        !(ts.hasModifier(current.parent, 32 /* Static */)) &&
+                                        ts.isClassLike(current.parent.parent));
+                            })) {
+                                return;
+                            }
+                            // fall through to report error
+                        }
+                        error(n, ts.Diagnostics.Initializer_of_parameter_0_cannot_reference_identifier_1_declared_after_it, ts.declarationNameToString(node.name), ts.declarationNameToString(n));
+                    }
+                }
+                else {
+                    return ts.forEachChild(n, visit);
+                }
+            }
+        }
+        function convertAutoToAny(type) {
+            return type === autoType ? anyType : type === autoArrayType ? anyArrayType : type;
+        }
+        // Check variable, parameter, or property declaration
+        function checkVariableLikeDeclaration(node) {
+            checkDecorators(node);
+            if (!ts.isBindingElement(node)) {
+                checkSourceElement(node.type);
+            }
+            // JSDoc `function(string, string): string` syntax results in parameters with no name
+            if (!node.name) {
+                return;
+            }
+            // For a computed property, just check the initializer and exit
+            // Do not use hasDynamicName here, because that returns false for well known symbols.
+            // We want to perform checkComputedPropertyName for all computed properties, including
+            // well known symbols.
+            if (node.name.kind === 147 /* ComputedPropertyName */) {
+                checkComputedPropertyName(node.name);
+                if (node.initializer) {
+                    checkExpressionCached(node.initializer);
+                }
+            }
+            if (node.kind === 182 /* BindingElement */) {
+                if (node.parent.kind === 180 /* ObjectBindingPattern */ && languageVersion < 6 /* ESNext */) {
+                    checkExternalEmitHelpers(node, 4 /* Rest */);
+                }
+                // check computed properties inside property names of binding elements
+                if (node.propertyName && node.propertyName.kind === 147 /* ComputedPropertyName */) {
+                    checkComputedPropertyName(node.propertyName);
+                }
+                // check private/protected variable access
+                var parent = node.parent.parent;
+                var parentType = getTypeForBindingElementParent(parent);
+                var name = node.propertyName || node.name;
+                if (!ts.isBindingPattern(name)) {
+                    var property = getPropertyOfType(parentType, ts.getTextOfPropertyName(name)); // TODO: GH#18217
+                    markPropertyAsReferenced(property, /*nodeForCheckWriteOnly*/ undefined, /*isThisAccess*/ false); // A destructuring is never a write-only reference.
+                    if (parent.initializer && property) {
+                        checkPropertyAccessibility(parent, parent.initializer, parentType, property);
+                    }
+                }
+            }
+            // For a binding pattern, check contained binding elements
+            if (ts.isBindingPattern(node.name)) {
+                if (node.name.kind === 181 /* ArrayBindingPattern */ && languageVersion < 2 /* ES2015 */ && compilerOptions.downlevelIteration) {
+                    checkExternalEmitHelpers(node, 512 /* Read */);
+                }
+                ts.forEach(node.name.elements, checkSourceElement);
+            }
+            // For a parameter declaration with an initializer, error and exit if the containing function doesn't have a body
+            if (node.initializer && ts.getRootDeclaration(node).kind === 149 /* Parameter */ && ts.nodeIsMissing(ts.getContainingFunction(node).body)) {
+                error(node, ts.Diagnostics.A_parameter_initializer_is_only_allowed_in_a_function_or_constructor_implementation);
+                return;
+            }
+            // For a binding pattern, validate the initializer and exit
+            if (ts.isBindingPattern(node.name)) {
+                // Don't validate for-in initializer as it is already an error
+                if (node.initializer && node.parent.parent.kind !== 221 /* ForInStatement */) {
+                    var initializerType = checkExpressionCached(node.initializer);
+                    if (strictNullChecks && node.name.elements.length === 0) {
+                        checkNonNullType(initializerType, node);
+                    }
+                    else {
+                        checkTypeAssignableTo(initializerType, getWidenedTypeForVariableLikeDeclaration(node), node, /*headMessage*/ undefined);
+                    }
+                    checkParameterInitializer(node);
+                }
+                return;
+            }
+            var symbol = getSymbolOfNode(node);
+            var type = convertAutoToAny(getTypeOfSymbol(symbol));
+            if (node === symbol.valueDeclaration) {
+                // Node is the primary declaration of the symbol, just validate the initializer
+                // Don't validate for-in initializer as it is already an error
+                var initializer = ts.getEffectiveInitializer(node);
+                if (initializer && node.parent.parent.kind !== 221 /* ForInStatement */) {
+                    checkTypeAssignableTo(checkExpressionCached(initializer), type, node, /*headMessage*/ undefined);
+                    checkParameterInitializer(node);
+                }
+            }
+            else {
+                // Node is a secondary declaration, check that type is identical to primary declaration and check that
+                // initializer is consistent with type associated with the node
+                var declarationType = convertAutoToAny(getWidenedTypeForVariableLikeDeclaration(node));
+                if (type !== errorType && declarationType !== errorType &&
+                    !isTypeIdenticalTo(type, declarationType) &&
+                    !(symbol.flags & 67108864 /* JSContainer */)) {
+                    errorNextVariableOrPropertyDeclarationMustHaveSameType(type, node, declarationType);
+                }
+                if (node.initializer) {
+                    checkTypeAssignableTo(checkExpressionCached(node.initializer), declarationType, node, /*headMessage*/ undefined);
+                }
+                if (!areDeclarationFlagsIdentical(node, symbol.valueDeclaration)) {
+                    error(ts.getNameOfDeclaration(symbol.valueDeclaration), ts.Diagnostics.All_declarations_of_0_must_have_identical_modifiers, ts.declarationNameToString(node.name));
+                    error(node.name, ts.Diagnostics.All_declarations_of_0_must_have_identical_modifiers, ts.declarationNameToString(node.name));
+                }
+            }
+            if (node.kind !== 152 /* PropertyDeclaration */ && node.kind !== 151 /* PropertySignature */) {
+                // We know we don't have a binding pattern or computed name here
+                checkExportsOnMergedDeclarations(node);
+                if (node.kind === 232 /* VariableDeclaration */ || node.kind === 182 /* BindingElement */) {
+                    checkVarDeclaredNamesNotShadowed(node);
+                }
+                checkCollisionWithRequireExportsInGeneratedCode(node, node.name);
+                checkCollisionWithGlobalPromiseInGeneratedCode(node, node.name);
+            }
+        }
+        function errorNextVariableOrPropertyDeclarationMustHaveSameType(firstType, nextDeclaration, nextType) {
+            var nextDeclarationName = ts.getNameOfDeclaration(nextDeclaration);
+            var message = nextDeclaration.kind === 152 /* PropertyDeclaration */ || nextDeclaration.kind === 151 /* PropertySignature */
+                ? ts.Diagnostics.Subsequent_property_declarations_must_have_the_same_type_Property_0_must_be_of_type_1_but_here_has_type_2
+                : ts.Diagnostics.Subsequent_variable_declarations_must_have_the_same_type_Variable_0_must_be_of_type_1_but_here_has_type_2;
+            error(nextDeclarationName, message, ts.declarationNameToString(nextDeclarationName), typeToString(firstType), typeToString(nextType));
+        }
+        function areDeclarationFlagsIdentical(left, right) {
+            if ((left.kind === 149 /* Parameter */ && right.kind === 232 /* VariableDeclaration */) ||
+                (left.kind === 232 /* VariableDeclaration */ && right.kind === 149 /* Parameter */)) {
+                // Differences in optionality between parameters and variables are allowed.
+                return true;
+            }
+            if (ts.hasQuestionToken(left) !== ts.hasQuestionToken(right)) {
+                return false;
+            }
+            var interestingFlags = 8 /* Private */ |
+                16 /* Protected */ |
+                256 /* Async */ |
+                128 /* Abstract */ |
+                64 /* Readonly */ |
+                32 /* Static */;
+            return ts.getSelectedModifierFlags(left, interestingFlags) === ts.getSelectedModifierFlags(right, interestingFlags);
+        }
+        function checkVariableDeclaration(node) {
+            checkGrammarVariableDeclaration(node);
+            return checkVariableLikeDeclaration(node);
+        }
+        function checkBindingElement(node) {
+            checkGrammarBindingElement(node);
+            return checkVariableLikeDeclaration(node);
+        }
+        function checkVariableStatement(node) {
+            // Grammar checking
+            if (!checkGrammarDecoratorsAndModifiers(node) && !checkGrammarVariableDeclarationList(node.declarationList))
+                checkGrammarForDisallowedLetOrConstStatement(node);
+            ts.forEach(node.declarationList.declarations, checkSourceElement);
+        }
+        function checkExpressionStatement(node) {
+            // Grammar checking
+            checkGrammarStatementInAmbientContext(node);
+            checkExpression(node.expression);
+        }
+        function checkIfStatement(node) {
+            // Grammar checking
+            checkGrammarStatementInAmbientContext(node);
+            checkExpression(node.expression);
+            checkSourceElement(node.thenStatement);
+            if (node.thenStatement.kind === 215 /* EmptyStatement */) {
+                error(node.thenStatement, ts.Diagnostics.The_body_of_an_if_statement_cannot_be_the_empty_statement);
+            }
+            checkSourceElement(node.elseStatement);
+        }
+        function checkDoStatement(node) {
+            // Grammar checking
+            checkGrammarStatementInAmbientContext(node);
+            checkSourceElement(node.statement);
+            checkExpression(node.expression);
+        }
+        function checkWhileStatement(node) {
+            // Grammar checking
+            checkGrammarStatementInAmbientContext(node);
+            checkExpression(node.expression);
+            checkSourceElement(node.statement);
+        }
+        function checkForStatement(node) {
+            // Grammar checking
+            if (!checkGrammarStatementInAmbientContext(node)) {
+                if (node.initializer && node.initializer.kind === 233 /* VariableDeclarationList */) {
+                    checkGrammarVariableDeclarationList(node.initializer);
+                }
+            }
+            if (node.initializer) {
+                if (node.initializer.kind === 233 /* VariableDeclarationList */) {
+                    ts.forEach(node.initializer.declarations, checkVariableDeclaration);
+                }
+                else {
+                    checkExpression(node.initializer);
+                }
+            }
+            if (node.condition)
+                checkExpression(node.condition);
+            if (node.incrementor)
+                checkExpression(node.incrementor);
+            checkSourceElement(node.statement);
+            if (node.locals) {
+                registerForUnusedIdentifiersCheck(node);
+            }
+        }
+        function checkForOfStatement(node) {
+            checkGrammarForInOrForOfStatement(node);
+            if (node.awaitModifier) {
+                var functionFlags = ts.getFunctionFlags(ts.getContainingFunction(node));
+                if ((functionFlags & (4 /* Invalid */ | 2 /* Async */)) === 2 /* Async */ && languageVersion < 6 /* ESNext */) {
+                    // for..await..of in an async function or async generator function prior to ESNext requires the __asyncValues helper
+                    checkExternalEmitHelpers(node, 16384 /* ForAwaitOfIncludes */);
+                }
+            }
+            else if (compilerOptions.downlevelIteration && languageVersion < 2 /* ES2015 */) {
+                // for..of prior to ES2015 requires the __values helper when downlevelIteration is enabled
+                checkExternalEmitHelpers(node, 256 /* ForOfIncludes */);
+            }
+            // Check the LHS and RHS
+            // If the LHS is a declaration, just check it as a variable declaration, which will in turn check the RHS
+            // via checkRightHandSideOfForOf.
+            // If the LHS is an expression, check the LHS, as a destructuring assignment or as a reference.
+            // Then check that the RHS is assignable to it.
+            if (node.initializer.kind === 233 /* VariableDeclarationList */) {
+                checkForInOrForOfVariableDeclaration(node);
+            }
+            else {
+                var varExpr = node.initializer;
+                var iteratedType = checkRightHandSideOfForOf(node.expression, node.awaitModifier);
+                // There may be a destructuring assignment on the left side
+                if (varExpr.kind === 183 /* ArrayLiteralExpression */ || varExpr.kind === 184 /* ObjectLiteralExpression */) {
+                    // iteratedType may be undefined. In this case, we still want to check the structure of
+                    // varExpr, in particular making sure it's a valid LeftHandSideExpression. But we'd like
+                    // to short circuit the type relation checking as much as possible, so we pass the unknownType.
+                    checkDestructuringAssignment(varExpr, iteratedType || errorType);
+                }
+                else {
+                    var leftType = checkExpression(varExpr);
+                    checkReferenceExpression(varExpr, ts.Diagnostics.The_left_hand_side_of_a_for_of_statement_must_be_a_variable_or_a_property_access);
+                    // iteratedType will be undefined if the rightType was missing properties/signatures
+                    // required to get its iteratedType (like [Symbol.iterator] or next). This may be
+                    // because we accessed properties from anyType, or it may have led to an error inside
+                    // getElementTypeOfIterable.
+                    if (iteratedType) {
+                        checkTypeAssignableTo(iteratedType, leftType, varExpr, /*headMessage*/ undefined);
+                    }
+                }
+            }
+            checkSourceElement(node.statement);
+            if (node.locals) {
+                registerForUnusedIdentifiersCheck(node);
+            }
+        }
+        function checkForInStatement(node) {
+            // Grammar checking
+            checkGrammarForInOrForOfStatement(node);
+            var rightType = checkNonNullExpression(node.expression);
+            // TypeScript 1.0 spec (April 2014): 5.4
+            // In a 'for-in' statement of the form
+            // for (let VarDecl in Expr) Statement
+            //   VarDecl must be a variable declaration without a type annotation that declares a variable of type Any,
+            //   and Expr must be an expression of type Any, an object type, or a type parameter type.
+            if (node.initializer.kind === 233 /* VariableDeclarationList */) {
+                var variable = node.initializer.declarations[0];
+                if (variable && ts.isBindingPattern(variable.name)) {
+                    error(variable.name, ts.Diagnostics.The_left_hand_side_of_a_for_in_statement_cannot_be_a_destructuring_pattern);
+                }
+                checkForInOrForOfVariableDeclaration(node);
+            }
+            else {
+                // In a 'for-in' statement of the form
+                // for (Var in Expr) Statement
+                //   Var must be an expression classified as a reference of type Any or the String primitive type,
+                //   and Expr must be an expression of type Any, an object type, or a type parameter type.
+                var varExpr = node.initializer;
+                var leftType = checkExpression(varExpr);
+                if (varExpr.kind === 183 /* ArrayLiteralExpression */ || varExpr.kind === 184 /* ObjectLiteralExpression */) {
+                    error(varExpr, ts.Diagnostics.The_left_hand_side_of_a_for_in_statement_cannot_be_a_destructuring_pattern);
+                }
+                else if (!isTypeAssignableTo(getIndexTypeOrString(rightType), leftType)) {
+                    error(varExpr, ts.Diagnostics.The_left_hand_side_of_a_for_in_statement_must_be_of_type_string_or_any);
+                }
+                else {
+                    // run check only former check succeeded to avoid cascading errors
+                    checkReferenceExpression(varExpr, ts.Diagnostics.The_left_hand_side_of_a_for_in_statement_must_be_a_variable_or_a_property_access);
+                }
+            }
+            // unknownType is returned i.e. if node.expression is identifier whose name cannot be resolved
+            // in this case error about missing name is already reported - do not report extra one
+            if (rightType === neverType || !isTypeAssignableToKind(rightType, 16777216 /* NonPrimitive */ | 14745600 /* InstantiableNonPrimitive */)) {
+                error(node.expression, ts.Diagnostics.The_right_hand_side_of_a_for_in_statement_must_be_of_type_any_an_object_type_or_a_type_parameter_but_here_has_type_0, typeToString(rightType));
+            }
+            checkSourceElement(node.statement);
+            if (node.locals) {
+                registerForUnusedIdentifiersCheck(node);
+            }
+        }
+        function checkForInOrForOfVariableDeclaration(iterationStatement) {
+            var variableDeclarationList = iterationStatement.initializer;
+            // checkGrammarForInOrForOfStatement will check that there is exactly one declaration.
+            if (variableDeclarationList.declarations.length >= 1) {
+                var decl = variableDeclarationList.declarations[0];
+                checkVariableDeclaration(decl);
+            }
+        }
+        function checkRightHandSideOfForOf(rhsExpression, awaitModifier) {
+            var expressionType = checkNonNullExpression(rhsExpression);
+            return checkIteratedTypeOrElementType(expressionType, rhsExpression, /*allowStringInput*/ true, awaitModifier !== undefined);
+        }
+        function checkIteratedTypeOrElementType(inputType, errorNode, allowStringInput, allowAsyncIterables) {
+            if (isTypeAny(inputType)) {
+                return inputType;
+            }
+            return getIteratedTypeOrElementType(inputType, errorNode, allowStringInput, allowAsyncIterables, /*checkAssignability*/ true) || anyType;
+        }
+        /**
+         * When consuming an iterable type in a for..of, spread, or iterator destructuring assignment
+         * we want to get the iterated type of an iterable for ES2015 or later, or the iterated type
+         * of a iterable (if defined globally) or element type of an array like for ES2015 or earlier.
+         */
+        function getIteratedTypeOrElementType(inputType, errorNode, allowStringInput, allowAsyncIterables, checkAssignability) {
+            if (inputType === neverType) {
+                reportTypeNotIterableError(errorNode, inputType, allowAsyncIterables); // TODO: GH#18217
+                return undefined;
+            }
+            var uplevelIteration = languageVersion >= 2 /* ES2015 */;
+            var downlevelIteration = !uplevelIteration && compilerOptions.downlevelIteration;
+            // Get the iterated type of an `Iterable<T>` or `IterableIterator<T>` only in ES2015
+            // or higher, when inside of an async generator or for-await-if, or when
+            // downlevelIteration is requested.
+            if (uplevelIteration || downlevelIteration || allowAsyncIterables) {
+                // We only report errors for an invalid iterable type in ES2015 or higher.
+                var iteratedType = getIteratedTypeOfIterable(inputType, uplevelIteration ? errorNode : undefined, allowAsyncIterables, /*allowSyncIterables*/ true, checkAssignability);
+                if (iteratedType || uplevelIteration) {
+                    return iteratedType;
+                }
+            }
+            var arrayType = inputType;
+            var reportedError = false;
+            var hasStringConstituent = false;
+            // If strings are permitted, remove any string-like constituents from the array type.
+            // This allows us to find other non-string element types from an array unioned with
+            // a string.
+            if (allowStringInput) {
+                if (arrayType.flags & 262144 /* Union */) {
+                    // After we remove all types that are StringLike, we will know if there was a string constituent
+                    // based on whether the result of filter is a new array.
+                    var arrayTypes = inputType.types;
+                    var filteredTypes = ts.filter(arrayTypes, function (t) { return !(t.flags & 68 /* StringLike */); });
+                    if (filteredTypes !== arrayTypes) {
+                        arrayType = getUnionType(filteredTypes, 2 /* Subtype */);
+                    }
+                }
+                else if (arrayType.flags & 68 /* StringLike */) {
+                    arrayType = neverType;
+                }
+                hasStringConstituent = arrayType !== inputType;
+                if (hasStringConstituent) {
+                    if (languageVersion < 1 /* ES5 */) {
+                        if (errorNode) {
+                            error(errorNode, ts.Diagnostics.Using_a_string_in_a_for_of_statement_is_only_supported_in_ECMAScript_5_and_higher);
+                            reportedError = true;
+                        }
+                    }
+                    // Now that we've removed all the StringLike types, if no constituents remain, then the entire
+                    // arrayOrStringType was a string.
+                    if (arrayType.flags & 32768 /* Never */) {
+                        return stringType;
+                    }
+                }
+            }
+            if (!isArrayLikeType(arrayType)) {
+                if (errorNode && !reportedError) {
+                    // Which error we report depends on whether we allow strings or if there was a
+                    // string constituent. For example, if the input type is number | string, we
+                    // want to say that number is not an array type. But if the input was just
+                    // number and string input is allowed, we want to say that number is not an
+                    // array type or a string type.
+                    var isIterable = !!getIteratedTypeOfIterable(inputType, /* errorNode */ undefined, allowAsyncIterables, /*allowSyncIterables*/ true, checkAssignability);
+                    var diagnostic = !allowStringInput || hasStringConstituent
+                        ? downlevelIteration
+                            ? ts.Diagnostics.Type_0_is_not_an_array_type_or_does_not_have_a_Symbol_iterator_method_that_returns_an_iterator
+                            : isIterable
+                                ? ts.Diagnostics.Type_0_is_not_an_array_type_Use_compiler_option_downlevelIteration_to_allow_iterating_of_iterators
+                                : ts.Diagnostics.Type_0_is_not_an_array_type
+                        : downlevelIteration
+                            ? ts.Diagnostics.Type_0_is_not_an_array_type_or_a_string_type_or_does_not_have_a_Symbol_iterator_method_that_returns_an_iterator
+                            : isIterable
+                                ? ts.Diagnostics.Type_0_is_not_an_array_type_or_a_string_type_Use_compiler_option_downlevelIteration_to_allow_iterating_of_iterators
+                                : ts.Diagnostics.Type_0_is_not_an_array_type_or_a_string_type;
+                    error(errorNode, diagnostic, typeToString(arrayType));
+                }
+                return hasStringConstituent ? stringType : undefined;
+            }
+            var arrayElementType = getIndexTypeOfType(arrayType, 1 /* Number */);
+            if (hasStringConstituent && arrayElementType) {
+                // This is just an optimization for the case where arrayOrStringType is string | string[]
+                if (arrayElementType.flags & 68 /* StringLike */) {
+                    return stringType;
+                }
+                return getUnionType([arrayElementType, stringType], 2 /* Subtype */);
+            }
+            return arrayElementType;
+        }
+        /**
+         * We want to treat type as an iterable, and get the type it is an iterable of. The iterable
+         * must have the following structure (annotated with the names of the variables below):
+         *
+         *     { // iterable
+         *         [Symbol.iterator]: { // iteratorMethod
+         *             (): Iterator<T>
+         *         }
+         *     }
+         *
+         * For an async iterable, we expect the following structure:
+         *
+         *     { // iterable
+         *         [Symbol.asyncIterator]: { // iteratorMethod
+         *             (): AsyncIterator<T>
+         *         }
+         *     }
+         *
+         * T is the type we are after. At every level that involves analyzing return types
+         * of signatures, we union the return types of all the signatures.
+         *
+         * Another thing to note is that at any step of this process, we could run into a dead end,
+         * meaning either the property is missing, or we run into the anyType. If either of these things
+         * happens, we return undefined to signal that we could not find the iterated type. If a property
+         * is missing, and the previous step did not result in 'any', then we also give an error if the
+         * caller requested it. Then the caller can decide what to do in the case where there is no iterated
+         * type. This is different from returning anyType, because that would signify that we have matched the
+         * whole pattern and that T (above) is 'any'.
+         *
+         * For a **for-of** statement, `yield*` (in a normal generator), spread, array
+         * destructuring, or normal generator we will only ever look for a `[Symbol.iterator]()`
+         * method.
+         *
+         * For an async generator we will only ever look at the `[Symbol.asyncIterator]()` method.
+         *
+         * For a **for-await-of** statement or a `yield*` in an async generator we will look for
+         * the `[Symbol.asyncIterator]()` method first, and then the `[Symbol.iterator]()` method.
+         */
+        function getIteratedTypeOfIterable(type, errorNode, allowAsyncIterables, allowSyncIterables, checkAssignability) {
+            if (isTypeAny(type)) {
+                return undefined;
+            }
+            return mapType(type, getIteratedType);
+            function getIteratedType(type) {
+                var typeAsIterable = type;
+                if (allowAsyncIterables) {
+                    if (typeAsIterable.iteratedTypeOfAsyncIterable) {
+                        return typeAsIterable.iteratedTypeOfAsyncIterable;
+                    }
+                    // As an optimization, if the type is an instantiation of the global `AsyncIterable<T>`
+                    // or the global `AsyncIterableIterator<T>` then just grab its type argument.
+                    if (isReferenceToType(type, getGlobalAsyncIterableType(/*reportErrors*/ false)) ||
+                        isReferenceToType(type, getGlobalAsyncIterableIteratorType(/*reportErrors*/ false))) {
+                        return typeAsIterable.iteratedTypeOfAsyncIterable = type.typeArguments[0];
+                    }
+                }
+                if (allowSyncIterables) {
+                    if (typeAsIterable.iteratedTypeOfIterable) {
+                        return typeAsIterable.iteratedTypeOfIterable;
+                    }
+                    // As an optimization, if the type is an instantiation of the global `Iterable<T>` or
+                    // `IterableIterator<T>` then just grab its type argument.
+                    if (isReferenceToType(type, getGlobalIterableType(/*reportErrors*/ false)) ||
+                        isReferenceToType(type, getGlobalIterableIteratorType(/*reportErrors*/ false))) {
+                        return typeAsIterable.iteratedTypeOfIterable = type.typeArguments[0];
+                    }
+                }
+                var asyncMethodType = allowAsyncIterables && getTypeOfPropertyOfType(type, ts.getPropertyNameForKnownSymbolName("asyncIterator"));
+                var methodType = asyncMethodType || (allowSyncIterables ? getTypeOfPropertyOfType(type, ts.getPropertyNameForKnownSymbolName("iterator")) : undefined);
+                if (isTypeAny(methodType)) {
+                    return undefined;
+                }
+                var signatures = methodType ? getSignaturesOfType(methodType, 0 /* Call */) : undefined;
+                if (!ts.some(signatures)) {
+                    if (errorNode) {
+                        // only report on the first error
+                        reportTypeNotIterableError(errorNode, type, allowAsyncIterables);
+                        errorNode = undefined;
+                    }
+                    return undefined;
+                }
+                var returnType = getUnionType(ts.map(signatures, getReturnTypeOfSignature), 2 /* Subtype */);
+                var iteratedType = getIteratedTypeOfIterator(returnType, errorNode, /*isAsyncIterator*/ !!asyncMethodType);
+                if (checkAssignability && errorNode && iteratedType) {
+                    // If `checkAssignability` was specified, we were called from
+                    // `checkIteratedTypeOrElementType`. As such, we need to validate that
+                    // the type passed in is actually an Iterable.
+                    checkTypeAssignableTo(type, asyncMethodType
+                        ? createAsyncIterableType(iteratedType)
+                        : createIterableType(iteratedType), errorNode);
+                }
+                return asyncMethodType
+                    ? typeAsIterable.iteratedTypeOfAsyncIterable = iteratedType
+                    : typeAsIterable.iteratedTypeOfIterable = iteratedType;
+            }
+        }
+        function reportTypeNotIterableError(errorNode, type, allowAsyncIterables) {
+            error(errorNode, allowAsyncIterables
+                ? ts.Diagnostics.Type_0_must_have_a_Symbol_asyncIterator_method_that_returns_an_async_iterator
+                : ts.Diagnostics.Type_0_must_have_a_Symbol_iterator_method_that_returns_an_iterator, typeToString(type));
+        }
+        /**
+         * This function has very similar logic as getIteratedTypeOfIterable, except that it operates on
+         * Iterators instead of Iterables. Here is the structure:
+         *
+         *  { // iterator
+         *      next: { // nextMethod
+         *          (): { // nextResult
+         *              value: T // nextValue
+         *          }
+         *      }
+         *  }
+         *
+         * For an async iterator, we expect the following structure:
+         *
+         *  { // iterator
+         *      next: { // nextMethod
+         *          (): PromiseLike<{ // nextResult
+         *              value: T // nextValue
+         *          }>
+         *      }
+         *  }
+         */
+        function getIteratedTypeOfIterator(type, errorNode, isAsyncIterator) {
+            if (isTypeAny(type)) {
+                return undefined;
+            }
+            var typeAsIterator = type;
+            if (isAsyncIterator ? typeAsIterator.iteratedTypeOfAsyncIterator : typeAsIterator.iteratedTypeOfIterator) {
+                return isAsyncIterator ? typeAsIterator.iteratedTypeOfAsyncIterator : typeAsIterator.iteratedTypeOfIterator;
+            }
+            // As an optimization, if the type is an instantiation of the global `Iterator<T>` (for
+            // a non-async iterator) or the global `AsyncIterator<T>` (for an async-iterator) then
+            // just grab its type argument.
+            var getIteratorType = isAsyncIterator ? getGlobalAsyncIteratorType : getGlobalIteratorType;
+            if (isReferenceToType(type, getIteratorType(/*reportErrors*/ false))) {
+                return isAsyncIterator
+                    ? typeAsIterator.iteratedTypeOfAsyncIterator = type.typeArguments[0]
+                    : typeAsIterator.iteratedTypeOfIterator = type.typeArguments[0];
+            }
+            // Both async and non-async iterators must have a `next` method.
+            var nextMethod = getTypeOfPropertyOfType(type, "next");
+            if (isTypeAny(nextMethod)) {
+                return undefined;
+            }
+            var nextMethodSignatures = nextMethod ? getSignaturesOfType(nextMethod, 0 /* Call */) : ts.emptyArray;
+            if (nextMethodSignatures.length === 0) {
+                if (errorNode) {
+                    error(errorNode, isAsyncIterator
+                        ? ts.Diagnostics.An_async_iterator_must_have_a_next_method
+                        : ts.Diagnostics.An_iterator_must_have_a_next_method);
+                }
+                return undefined;
+            }
+            var nextResult = getUnionType(ts.map(nextMethodSignatures, getReturnTypeOfSignature), 2 /* Subtype */);
+            if (isTypeAny(nextResult)) {
+                return undefined;
+            }
+            // For an async iterator, we must get the awaited type of the return type.
+            if (isAsyncIterator) {
+                nextResult = getAwaitedTypeOfPromise(nextResult, errorNode, ts.Diagnostics.The_type_returned_by_the_next_method_of_an_async_iterator_must_be_a_promise_for_a_type_with_a_value_property);
+                if (isTypeAny(nextResult)) {
+                    return undefined;
+                }
+            }
+            var nextValue = nextResult && getTypeOfPropertyOfType(nextResult, "value");
+            if (!nextValue) {
+                if (errorNode) {
+                    error(errorNode, isAsyncIterator
+                        ? ts.Diagnostics.The_type_returned_by_the_next_method_of_an_async_iterator_must_be_a_promise_for_a_type_with_a_value_property
+                        : ts.Diagnostics.The_type_returned_by_the_next_method_of_an_iterator_must_have_a_value_property);
+                }
+                return undefined;
+            }
+            return isAsyncIterator
+                ? typeAsIterator.iteratedTypeOfAsyncIterator = nextValue
+                : typeAsIterator.iteratedTypeOfIterator = nextValue;
+        }
+        /**
+         * A generator may have a return type of `Iterator<T>`, `Iterable<T>`, or
+         * `IterableIterator<T>`. An async generator may have a return type of `AsyncIterator<T>`,
+         * `AsyncIterable<T>`, or `AsyncIterableIterator<T>`. This function can be used to extract
+         * the iterated type from this return type for contextual typing and verifying signatures.
+         */
+        function getIteratedTypeOfGenerator(returnType, isAsyncGenerator) {
+            if (isTypeAny(returnType)) {
+                return undefined;
+            }
+            return getIteratedTypeOfIterable(returnType, /*errorNode*/ undefined, /*allowAsyncIterables*/ isAsyncGenerator, /*allowSyncIterables*/ !isAsyncGenerator, /*checkAssignability*/ false)
+                || getIteratedTypeOfIterator(returnType, /*errorNode*/ undefined, isAsyncGenerator);
+        }
+        function checkBreakOrContinueStatement(node) {
+            // Grammar checking
+            if (!checkGrammarStatementInAmbientContext(node))
+                checkGrammarBreakOrContinueStatement(node);
+            // TODO: Check that target label is valid
+        }
+        function isGetAccessorWithAnnotatedSetAccessor(node) {
+            return node.kind === 156 /* GetAccessor */
+                && ts.getEffectiveSetAccessorTypeAnnotationNode(ts.getDeclarationOfKind(node.symbol, 157 /* SetAccessor */)) !== undefined;
+        }
+        function isUnwrappedReturnTypeVoidOrAny(func, returnType) {
+            var unwrappedReturnType = (ts.getFunctionFlags(func) & 3 /* AsyncGenerator */) === 2 /* Async */
+                ? getPromisedTypeOfPromise(returnType) // Async function
+                : returnType; // AsyncGenerator function, Generator function, or normal function
+            return !!unwrappedReturnType && maybeTypeOfKind(unwrappedReturnType, 4096 /* Void */ | 3 /* AnyOrUnknown */);
+        }
+        function checkReturnStatement(node) {
+            // Grammar checking
+            if (checkGrammarStatementInAmbientContext(node)) {
+                return;
+            }
+            var func = ts.getContainingFunction(node);
+            if (!func) {
+                grammarErrorOnFirstToken(node, ts.Diagnostics.A_return_statement_can_only_be_used_within_a_function_body);
+                return;
+            }
+            var signature = getSignatureFromDeclaration(func);
+            var returnType = getReturnTypeOfSignature(signature);
+            var functionFlags = ts.getFunctionFlags(func);
+            var isGenerator = functionFlags & 1 /* Generator */;
+            if (strictNullChecks || node.expression || returnType.flags & 32768 /* Never */) {
+                var exprType = node.expression ? checkExpressionCached(node.expression) : undefinedType;
+                if (isGenerator) { // AsyncGenerator function or Generator function
+                    // A generator does not need its return expressions checked against its return type.
+                    // Instead, the yield expressions are checked against the element type.
+                    // TODO: Check return types of generators when return type tracking is added
+                    // for generators.
+                    return;
+                }
+                else if (func.kind === 157 /* SetAccessor */) {
+                    if (node.expression) {
+                        error(node, ts.Diagnostics.Setters_cannot_return_a_value);
+                    }
+                }
+                else if (func.kind === 155 /* Constructor */) {
+                    if (node.expression && !checkTypeAssignableTo(exprType, returnType, node)) {
+                        error(node, ts.Diagnostics.Return_type_of_constructor_signature_must_be_assignable_to_the_instance_type_of_the_class);
+                    }
+                }
+                else if (ts.getEffectiveReturnTypeNode(func) || isGetAccessorWithAnnotatedSetAccessor(func)) {
+                    if (functionFlags & 2 /* Async */) { // Async function
+                        var promisedType = getPromisedTypeOfPromise(returnType);
+                        var awaitedType = checkAwaitedType(exprType, node, ts.Diagnostics.The_return_type_of_an_async_function_must_either_be_a_valid_promise_or_must_not_contain_a_callable_then_member);
+                        if (promisedType) {
+                            // If the function has a return type, but promisedType is
+                            // undefined, an error will be reported in checkAsyncFunctionReturnType
+                            // so we don't need to report one here.
+                            checkTypeAssignableTo(awaitedType, promisedType, node);
+                        }
+                    }
+                    else {
+                        checkTypeAssignableTo(exprType, returnType, node);
+                    }
+                }
+            }
+            else if (func.kind !== 155 /* Constructor */ && compilerOptions.noImplicitReturns && !isUnwrappedReturnTypeVoidOrAny(func, returnType) && !isGenerator) {
+                // The function has a return type, but the return statement doesn't have an expression.
+                error(node, ts.Diagnostics.Not_all_code_paths_return_a_value);
+            }
+        }
+        function checkWithStatement(node) {
+            // Grammar checking for withStatement
+            if (!checkGrammarStatementInAmbientContext(node)) {
+                if (node.flags & 16384 /* AwaitContext */) {
+                    grammarErrorOnFirstToken(node, ts.Diagnostics.with_statements_are_not_allowed_in_an_async_function_block);
+                }
+            }
+            checkExpression(node.expression);
+            var sourceFile = ts.getSourceFileOfNode(node);
+            if (!hasParseDiagnostics(sourceFile)) {
+                var start = ts.getSpanOfTokenAtPosition(sourceFile, node.pos).start;
+                var end = node.statement.pos;
+                grammarErrorAtPos(sourceFile, start, end - start, ts.Diagnostics.The_with_statement_is_not_supported_All_symbols_in_a_with_block_will_have_type_any);
+            }
+        }
+        function checkSwitchStatement(node) {
+            // Grammar checking
+            checkGrammarStatementInAmbientContext(node);
+            var firstDefaultClause;
+            var hasDuplicateDefaultClause = false;
+            var expressionType = checkExpression(node.expression);
+            var expressionIsLiteral = isLiteralType(expressionType);
+            ts.forEach(node.caseBlock.clauses, function (clause) {
+                // Grammar check for duplicate default clauses, skip if we already report duplicate default clause
+                if (clause.kind === 267 /* DefaultClause */ && !hasDuplicateDefaultClause) {
+                    if (firstDefaultClause === undefined) {
+                        firstDefaultClause = clause;
+                    }
+                    else {
+                        var sourceFile = ts.getSourceFileOfNode(node);
+                        var start = ts.skipTrivia(sourceFile.text, clause.pos);
+                        var end = clause.statements.length > 0 ? clause.statements[0].pos : clause.end;
+                        grammarErrorAtPos(sourceFile, start, end - start, ts.Diagnostics.A_default_clause_cannot_appear_more_than_once_in_a_switch_statement);
+                        hasDuplicateDefaultClause = true;
+                    }
+                }
+                if (produceDiagnostics && clause.kind === 266 /* CaseClause */) {
+                    // TypeScript 1.0 spec (April 2014): 5.9
+                    // In a 'switch' statement, each 'case' expression must be of a type that is comparable
+                    // to or from the type of the 'switch' expression.
+                    var caseType = checkExpression(clause.expression);
+                    var caseIsLiteral = isLiteralType(caseType);
+                    var comparedExpressionType = expressionType;
+                    if (!caseIsLiteral || !expressionIsLiteral) {
+                        caseType = caseIsLiteral ? getBaseTypeOfLiteralType(caseType) : caseType;
+                        comparedExpressionType = getBaseTypeOfLiteralType(expressionType);
+                    }
+                    if (!isTypeEqualityComparableTo(comparedExpressionType, caseType)) {
+                        // expressionType is not comparable to caseType, try the reversed check and report errors if it fails
+                        checkTypeComparableTo(caseType, comparedExpressionType, clause.expression, /*headMessage*/ undefined);
+                    }
+                }
+                ts.forEach(clause.statements, checkSourceElement);
+            });
+            if (node.caseBlock.locals) {
+                registerForUnusedIdentifiersCheck(node.caseBlock);
+            }
+        }
+        function checkLabeledStatement(node) {
+            // Grammar checking
+            if (!checkGrammarStatementInAmbientContext(node)) {
+                ts.findAncestor(node.parent, function (current) {
+                    if (ts.isFunctionLike(current)) {
+                        return "quit";
+                    }
+                    if (current.kind === 228 /* LabeledStatement */ && current.label.escapedText === node.label.escapedText) {
+                        grammarErrorOnNode(node.label, ts.Diagnostics.Duplicate_label_0, ts.getTextOfNode(node.label));
+                        return true;
+                    }
+                    return false;
+                });
+            }
+            // ensure that label is unique
+            checkSourceElement(node.statement);
+        }
+        function checkThrowStatement(node) {
+            // Grammar checking
+            if (!checkGrammarStatementInAmbientContext(node)) {
+                if (node.expression === undefined) {
+                    grammarErrorAfterFirstToken(node, ts.Diagnostics.Line_break_not_permitted_here);
+                }
+            }
+            if (node.expression) {
+                checkExpression(node.expression);
+            }
+        }
+        function checkTryStatement(node) {
+            // Grammar checking
+            checkGrammarStatementInAmbientContext(node);
+            checkBlock(node.tryBlock);
+            var catchClause = node.catchClause;
+            if (catchClause) {
+                // Grammar checking
+                if (catchClause.variableDeclaration) {
+                    if (catchClause.variableDeclaration.type) {
+                        grammarErrorOnFirstToken(catchClause.variableDeclaration.type, ts.Diagnostics.Catch_clause_variable_cannot_have_a_type_annotation);
+                    }
+                    else if (catchClause.variableDeclaration.initializer) {
+                        grammarErrorOnFirstToken(catchClause.variableDeclaration.initializer, ts.Diagnostics.Catch_clause_variable_cannot_have_an_initializer);
+                    }
+                    else {
+                        var blockLocals_1 = catchClause.block.locals;
+                        if (blockLocals_1) {
+                            ts.forEachKey(catchClause.locals, function (caughtName) {
+                                var blockLocal = blockLocals_1.get(caughtName);
+                                if (blockLocal && (blockLocal.flags & 2 /* BlockScopedVariable */) !== 0) {
+                                    grammarErrorOnNode(blockLocal.valueDeclaration, ts.Diagnostics.Cannot_redeclare_identifier_0_in_catch_clause, caughtName);
+                                }
+                            });
+                        }
+                    }
+                }
+                checkBlock(catchClause.block);
+            }
+            if (node.finallyBlock) {
+                checkBlock(node.finallyBlock);
+            }
+        }
+        function checkIndexConstraints(type) {
+            var declaredNumberIndexer = getIndexDeclarationOfSymbol(type.symbol, 1 /* Number */);
+            var declaredStringIndexer = getIndexDeclarationOfSymbol(type.symbol, 0 /* String */);
+            var stringIndexType = getIndexTypeOfType(type, 0 /* String */);
+            var numberIndexType = getIndexTypeOfType(type, 1 /* Number */);
+            if (stringIndexType || numberIndexType) {
+                ts.forEach(getPropertiesOfObjectType(type), function (prop) {
+                    var propType = getTypeOfSymbol(prop);
+                    checkIndexConstraintForProperty(prop, propType, type, declaredStringIndexer, stringIndexType, 0 /* String */);
+                    checkIndexConstraintForProperty(prop, propType, type, declaredNumberIndexer, numberIndexType, 1 /* Number */);
+                });
+                var classDeclaration = type.symbol.valueDeclaration;
+                if (ts.getObjectFlags(type) & 1 /* Class */ && ts.isClassLike(classDeclaration)) {
+                    for (var _i = 0, _a = classDeclaration.members; _i < _a.length; _i++) {
+                        var member = _a[_i];
+                        // Only process instance properties with computed names here.
+                        // Static properties cannot be in conflict with indexers,
+                        // and properties with literal names were already checked.
+                        if (!ts.hasModifier(member, 32 /* Static */) && hasNonBindableDynamicName(member)) {
+                            var symbol = getSymbolOfNode(member);
+                            var propType = getTypeOfSymbol(symbol);
+                            checkIndexConstraintForProperty(symbol, propType, type, declaredStringIndexer, stringIndexType, 0 /* String */);
+                            checkIndexConstraintForProperty(symbol, propType, type, declaredNumberIndexer, numberIndexType, 1 /* Number */);
+                        }
+                    }
+                }
+            }
+            var errorNode;
+            if (stringIndexType && numberIndexType) {
+                errorNode = declaredNumberIndexer || declaredStringIndexer;
+                // condition 'errorNode === undefined' may appear if types does not declare nor string neither number indexer
+                if (!errorNode && (ts.getObjectFlags(type) & 2 /* Interface */)) {
+                    var someBaseTypeHasBothIndexers = ts.forEach(getBaseTypes(type), function (base) { return getIndexTypeOfType(base, 0 /* String */) && getIndexTypeOfType(base, 1 /* Number */); });
+                    errorNode = someBaseTypeHasBothIndexers ? undefined : type.symbol.declarations[0];
+                }
+            }
+            if (errorNode && !isTypeAssignableTo(numberIndexType, stringIndexType)) { // TODO: GH#18217
+                error(errorNode, ts.Diagnostics.Numeric_index_type_0_is_not_assignable_to_string_index_type_1, typeToString(numberIndexType), typeToString(stringIndexType));
+            }
+            function checkIndexConstraintForProperty(prop, propertyType, containingType, indexDeclaration, indexType, indexKind) {
+                // ESSymbol properties apply to neither string nor numeric indexers.
+                if (!indexType || ts.isKnownSymbol(prop)) {
+                    return;
+                }
+                var propDeclaration = prop.valueDeclaration;
+                // index is numeric and property name is not valid numeric literal
+                if (indexKind === 1 /* Number */ && !(propDeclaration ? isNumericName(ts.getNameOfDeclaration(propDeclaration)) : isNumericLiteralName(prop.escapedName))) {
+                    return;
+                }
+                // perform property check if property or indexer is declared in 'type'
+                // this allows us to rule out cases when both property and indexer are inherited from the base class
+                var errorNode;
+                if (propDeclaration &&
+                    (propDeclaration.kind === 200 /* BinaryExpression */ ||
+                        ts.getNameOfDeclaration(propDeclaration).kind === 147 /* ComputedPropertyName */ ||
+                        prop.parent === containingType.symbol)) {
+                    errorNode = propDeclaration;
+                }
+                else if (indexDeclaration) {
+                    errorNode = indexDeclaration;
+                }
+                else if (ts.getObjectFlags(containingType) & 2 /* Interface */) {
+                    // for interfaces property and indexer might be inherited from different bases
+                    // check if any base class already has both property and indexer.
+                    // check should be performed only if 'type' is the first type that brings property\indexer together
+                    var someBaseClassHasBothPropertyAndIndexer = ts.forEach(getBaseTypes(containingType), function (base) { return getPropertyOfObjectType(base, prop.escapedName) && getIndexTypeOfType(base, indexKind); });
+                    errorNode = someBaseClassHasBothPropertyAndIndexer ? undefined : containingType.symbol.declarations[0];
+                }
+                if (errorNode && !isTypeAssignableTo(propertyType, indexType)) {
+                    var errorMessage = indexKind === 0 /* String */
+                        ? ts.Diagnostics.Property_0_of_type_1_is_not_assignable_to_string_index_type_2
+                        : ts.Diagnostics.Property_0_of_type_1_is_not_assignable_to_numeric_index_type_2;
+                    error(errorNode, errorMessage, symbolToString(prop), typeToString(propertyType), typeToString(indexType));
+                }
+            }
+        }
+        function checkTypeNameIsReserved(name, message) {
+            // TS 1.0 spec (April 2014): 3.6.1
+            // The predefined type keywords are reserved and cannot be used as names of user defined types.
+            switch (name.escapedText) {
+                case "any":
+                case "unknown":
+                case "number":
+                case "boolean":
+                case "string":
+                case "symbol":
+                case "void":
+                case "object":
+                    error(name, message, name.escapedText);
+            }
+        }
+        /**
+         * The name cannot be used as 'Object' of user defined types with special target.
+         */
+        function checkClassNameCollisionWithObject(name) {
+            if (languageVersion === 1 /* ES5 */ && name.escapedText === "Object"
+                && moduleKind !== ts.ModuleKind.ES2015 && moduleKind !== ts.ModuleKind.ESNext) {
+                error(name, ts.Diagnostics.Class_name_cannot_be_Object_when_targeting_ES5_with_module_0, ts.ModuleKind[moduleKind]); // https://github.com/Microsoft/TypeScript/issues/17494
+            }
+        }
+        /**
+         * Check each type parameter and check that type parameters have no duplicate type parameter declarations
+         */
+        function checkTypeParameters(typeParameterDeclarations) {
+            if (typeParameterDeclarations) {
+                var seenDefault = false;
+                for (var i = 0; i < typeParameterDeclarations.length; i++) {
+                    var node = typeParameterDeclarations[i];
+                    checkTypeParameter(node);
+                    if (produceDiagnostics) {
+                        if (node.default) {
+                            seenDefault = true;
+                        }
+                        else if (seenDefault) {
+                            error(node, ts.Diagnostics.Required_type_parameters_may_not_follow_optional_type_parameters);
+                        }
+                        for (var j = 0; j < i; j++) {
+                            if (typeParameterDeclarations[j].symbol === node.symbol) {
+                                error(node.name, ts.Diagnostics.Duplicate_identifier_0, ts.declarationNameToString(node.name));
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        /** Check that type parameter lists are identical across multiple declarations */
+        function checkTypeParameterListsIdentical(symbol) {
+            if (symbol.declarations.length === 1) {
+                return;
+            }
+            var links = getSymbolLinks(symbol);
+            if (!links.typeParametersChecked) {
+                links.typeParametersChecked = true;
+                var declarations = getClassOrInterfaceDeclarationsOfSymbol(symbol);
+                if (declarations.length <= 1) {
+                    return;
+                }
+                var type = getDeclaredTypeOfSymbol(symbol);
+                if (!areTypeParametersIdentical(declarations, type.localTypeParameters)) {
+                    // Report an error on every conflicting declaration.
+                    var name = symbolToString(symbol);
+                    for (var _i = 0, declarations_6 = declarations; _i < declarations_6.length; _i++) {
+                        var declaration = declarations_6[_i];
+                        error(declaration.name, ts.Diagnostics.All_declarations_of_0_must_have_identical_type_parameters, name);
+                    }
+                }
+            }
+        }
+        function areTypeParametersIdentical(declarations, targetParameters) {
+            var maxTypeArgumentCount = ts.length(targetParameters);
+            var minTypeArgumentCount = getMinTypeArgumentCount(targetParameters);
+            for (var _i = 0, declarations_7 = declarations; _i < declarations_7.length; _i++) {
+                var declaration = declarations_7[_i];
+                // If this declaration has too few or too many type parameters, we report an error
+                var sourceParameters = ts.getEffectiveTypeParameterDeclarations(declaration);
+                var numTypeParameters = sourceParameters.length;
+                if (numTypeParameters < minTypeArgumentCount || numTypeParameters > maxTypeArgumentCount) {
+                    return false;
+                }
+                for (var i = 0; i < numTypeParameters; i++) {
+                    var source = sourceParameters[i];
+                    var target = targetParameters[i];
+                    // If the type parameter node does not have the same as the resolved type
+                    // parameter at this position, we report an error.
+                    if (source.name.escapedText !== target.symbol.escapedName) {
+                        return false;
+                    }
+                    // If the type parameter node does not have an identical constraint as the resolved
+                    // type parameter at this position, we report an error.
+                    var sourceConstraint = source.constraint && getTypeFromTypeNode(source.constraint);
+                    var targetConstraint = getConstraintFromTypeParameter(target);
+                    if (sourceConstraint) {
+                        // relax check if later interface augmentation has no constraint
+                        if (!targetConstraint || !isTypeIdenticalTo(sourceConstraint, targetConstraint)) {
+                            return false;
+                        }
+                    }
+                    // If the type parameter node has a default and it is not identical to the default
+                    // for the type parameter at this position, we report an error.
+                    var sourceDefault = source.default && getTypeFromTypeNode(source.default);
+                    var targetDefault = getDefaultFromTypeParameter(target);
+                    if (sourceDefault && targetDefault && !isTypeIdenticalTo(sourceDefault, targetDefault)) {
+                        return false;
+                    }
+                }
+            }
+            return true;
+        }
+        function checkClassExpression(node) {
+            checkClassLikeDeclaration(node);
+            checkNodeDeferred(node);
+            return getTypeOfSymbol(getSymbolOfNode(node));
+        }
+        function checkClassExpressionDeferred(node) {
+            ts.forEach(node.members, checkSourceElement);
+            registerForUnusedIdentifiersCheck(node);
+        }
+        function checkClassDeclaration(node) {
+            if (!node.name && !ts.hasModifier(node, 512 /* Default */)) {
+                grammarErrorOnFirstToken(node, ts.Diagnostics.A_class_declaration_without_the_default_modifier_must_have_a_name);
+            }
+            checkClassLikeDeclaration(node);
+            ts.forEach(node.members, checkSourceElement);
+            registerForUnusedIdentifiersCheck(node);
+        }
+        function checkClassLikeDeclaration(node) {
+            checkGrammarClassLikeDeclaration(node);
+            checkDecorators(node);
+            if (node.name) {
+                checkTypeNameIsReserved(node.name, ts.Diagnostics.Class_name_cannot_be_0);
+                checkCollisionWithRequireExportsInGeneratedCode(node, node.name);
+                checkCollisionWithGlobalPromiseInGeneratedCode(node, node.name);
+                if (!(node.flags & 4194304 /* Ambient */)) {
+                    checkClassNameCollisionWithObject(node.name);
+                }
+            }
+            checkTypeParameters(ts.getEffectiveTypeParameterDeclarations(node));
+            checkExportsOnMergedDeclarations(node);
+            var symbol = getSymbolOfNode(node);
+            var type = getDeclaredTypeOfSymbol(symbol);
+            var typeWithThis = getTypeWithThisArgument(type);
+            var staticType = getTypeOfSymbol(symbol);
+            checkTypeParameterListsIdentical(symbol);
+            checkClassForDuplicateDeclarations(node);
+            // Only check for reserved static identifiers on non-ambient context.
+            if (!(node.flags & 4194304 /* Ambient */)) {
+                checkClassForStaticPropertyNameConflicts(node);
+            }
+            var baseTypeNode = ts.getClassExtendsHeritageClauseElement(node);
+            if (baseTypeNode) {
+                if (languageVersion < 2 /* ES2015 */) {
+                    checkExternalEmitHelpers(baseTypeNode.parent, 1 /* Extends */);
+                }
+                var baseTypes = getBaseTypes(type);
+                if (baseTypes.length && produceDiagnostics) {
+                    var baseType_1 = baseTypes[0];
+                    var baseConstructorType = getBaseConstructorTypeOfClass(type);
+                    var staticBaseType = getApparentType(baseConstructorType);
+                    checkBaseTypeAccessibility(staticBaseType, baseTypeNode);
+                    checkSourceElement(baseTypeNode.expression);
+                    if (ts.some(baseTypeNode.typeArguments)) {
+                        ts.forEach(baseTypeNode.typeArguments, checkSourceElement);
+                        for (var _i = 0, _a = getConstructorsForTypeArguments(staticBaseType, baseTypeNode.typeArguments, baseTypeNode); _i < _a.length; _i++) {
+                            var constructor = _a[_i];
+                            if (!checkTypeArgumentConstraints(baseTypeNode, constructor.typeParameters)) {
+                                break;
+                            }
+                        }
+                    }
+                    var baseWithThis = getTypeWithThisArgument(baseType_1, type.thisType);
+                    if (!checkTypeAssignableTo(typeWithThis, baseWithThis, /*errorNode*/ undefined)) {
+                        issueMemberSpecificError(node, typeWithThis, baseWithThis, ts.Diagnostics.Class_0_incorrectly_extends_base_class_1);
+                    }
+                    checkTypeAssignableTo(staticType, getTypeWithoutSignatures(staticBaseType), node.name || node, ts.Diagnostics.Class_static_side_0_incorrectly_extends_base_class_static_side_1);
+                    if (baseConstructorType.flags & 2162688 /* TypeVariable */ && !isMixinConstructorType(staticType)) {
+                        error(node.name || node, ts.Diagnostics.A_mixin_class_must_have_a_constructor_with_a_single_rest_parameter_of_type_any);
+                    }
+                    if (!(staticBaseType.symbol && staticBaseType.symbol.flags & 32 /* Class */) && !(baseConstructorType.flags & 2162688 /* TypeVariable */)) {
+                        // When the static base type is a "class-like" constructor function (but not actually a class), we verify
+                        // that all instantiated base constructor signatures return the same type. We can simply compare the type
+                        // references (as opposed to checking the structure of the types) because elsewhere we have already checked
+                        // that the base type is a class or interface type (and not, for example, an anonymous object type).
+                        var constructors = getInstantiatedConstructorsForTypeArguments(staticBaseType, baseTypeNode.typeArguments, baseTypeNode);
+                        if (ts.forEach(constructors, function (sig) { return getReturnTypeOfSignature(sig) !== baseType_1; })) {
+                            error(baseTypeNode.expression, ts.Diagnostics.Base_constructors_must_all_have_the_same_return_type);
+                        }
+                    }
+                    checkKindsOfPropertyMemberOverrides(type, baseType_1);
+                }
+            }
+            var implementedTypeNodes = ts.getClassImplementsHeritageClauseElements(node);
+            if (implementedTypeNodes) {
+                for (var _b = 0, implementedTypeNodes_1 = implementedTypeNodes; _b < implementedTypeNodes_1.length; _b++) {
+                    var typeRefNode = implementedTypeNodes_1[_b];
+                    if (!ts.isEntityNameExpression(typeRefNode.expression)) {
+                        error(typeRefNode.expression, ts.Diagnostics.A_class_can_only_implement_an_identifier_Slashqualified_name_with_optional_type_arguments);
+                    }
+                    checkTypeReferenceNode(typeRefNode);
+                    if (produceDiagnostics) {
+                        var t = getTypeFromTypeNode(typeRefNode);
+                        if (t !== errorType) {
+                            if (isValidBaseType(t)) {
+                                var genericDiag = t.symbol && t.symbol.flags & 32 /* Class */ ?
+                                    ts.Diagnostics.Class_0_incorrectly_implements_class_1_Did_you_mean_to_extend_1_and_inherit_its_members_as_a_subclass :
+                                    ts.Diagnostics.Class_0_incorrectly_implements_interface_1;
+                                var baseWithThis = getTypeWithThisArgument(t, type.thisType);
+                                if (!checkTypeAssignableTo(typeWithThis, baseWithThis, /*errorNode*/ undefined)) {
+                                    issueMemberSpecificError(node, typeWithThis, baseWithThis, genericDiag);
+                                }
+                            }
+                            else {
+                                error(typeRefNode, ts.Diagnostics.A_class_may_only_implement_another_class_or_interface);
+                            }
+                        }
+                    }
+                }
+            }
+            if (produceDiagnostics) {
+                checkIndexConstraints(type);
+                checkTypeForDuplicateIndexSignatures(node);
+                checkPropertyInitialization(node);
+            }
+        }
+        function issueMemberSpecificError(node, typeWithThis, baseWithThis, broadDiag) {
+            // iterate over all implemented properties and issue errors on each one which isn't compatible, rather than the class as a whole, if possible
+            var issuedMemberError = false;
+            var _loop_9 = function (member) {
+                if (ts.hasStaticModifier(member)) {
+                    return "continue";
+                }
+                var declaredProp = member.name && getSymbolAtLocation(member.name) || getSymbolAtLocation(member);
+                if (declaredProp) {
+                    var prop = getPropertyOfType(typeWithThis, declaredProp.escapedName);
+                    var baseProp = getPropertyOfType(baseWithThis, declaredProp.escapedName);
+                    if (prop && baseProp) {
+                        var rootChain = function () { return ts.chainDiagnosticMessages(
+                        /*details*/ undefined, ts.Diagnostics.Property_0_in_type_1_is_not_assignable_to_the_same_property_in_base_type_2, symbolToString(declaredProp), typeToString(typeWithThis), typeToString(baseWithThis)); };
+                        if (!checkTypeAssignableTo(getTypeOfSymbol(prop), getTypeOfSymbol(baseProp), member.name || member, /*message*/ undefined, rootChain)) {
+                            issuedMemberError = true;
+                        }
+                    }
+                }
+            };
+            for (var _i = 0, _a = node.members; _i < _a.length; _i++) {
+                var member = _a[_i];
+                _loop_9(member);
+            }
+            if (!issuedMemberError) {
+                // check again with diagnostics to generate a less-specific error
+                checkTypeAssignableTo(typeWithThis, baseWithThis, node.name || node, broadDiag);
+            }
+        }
+        function checkBaseTypeAccessibility(type, node) {
+            var signatures = getSignaturesOfType(type, 1 /* Construct */);
+            if (signatures.length) {
+                var declaration = signatures[0].declaration;
+                if (declaration && ts.hasModifier(declaration, 8 /* Private */)) {
+                    var typeClassDeclaration = ts.getClassLikeDeclarationOfSymbol(type.symbol);
+                    if (!isNodeWithinClass(node, typeClassDeclaration)) {
+                        error(node, ts.Diagnostics.Cannot_extend_a_class_0_Class_constructor_is_marked_as_private, getFullyQualifiedName(type.symbol));
+                    }
+                }
+            }
+        }
+        function getTargetSymbol(s) {
+            // if symbol is instantiated its flags are not copied from the 'target'
+            // so we'll need to get back original 'target' symbol to work with correct set of flags
+            return ts.getCheckFlags(s) & 1 /* Instantiated */ ? s.target : s;
+        }
+        function getClassOrInterfaceDeclarationsOfSymbol(symbol) {
+            return ts.filter(symbol.declarations, function (d) {
+                return d.kind === 235 /* ClassDeclaration */ || d.kind === 236 /* InterfaceDeclaration */;
+            });
+        }
+        function checkKindsOfPropertyMemberOverrides(type, baseType) {
+            // TypeScript 1.0 spec (April 2014): 8.2.3
+            // A derived class inherits all members from its base class it doesn't override.
+            // Inheritance means that a derived class implicitly contains all non - overridden members of the base class.
+            // Both public and private property members are inherited, but only public property members can be overridden.
+            // A property member in a derived class is said to override a property member in a base class
+            // when the derived class property member has the same name and kind(instance or static)
+            // as the base class property member.
+            // The type of an overriding property member must be assignable(section 3.8.4)
+            // to the type of the overridden property member, or otherwise a compile - time error occurs.
+            // Base class instance member functions can be overridden by derived class instance member functions,
+            // but not by other kinds of members.
+            // Base class instance member variables and accessors can be overridden by
+            // derived class instance member variables and accessors, but not by other kinds of members.
+            // NOTE: assignability is checked in checkClassDeclaration
+            var baseProperties = getPropertiesOfType(baseType);
+            for (var _i = 0, baseProperties_1 = baseProperties; _i < baseProperties_1.length; _i++) {
+                var baseProperty = baseProperties_1[_i];
+                var base = getTargetSymbol(baseProperty);
+                if (base.flags & 4194304 /* Prototype */) {
+                    continue;
+                }
+                var derived = getTargetSymbol(getPropertyOfObjectType(type, base.escapedName)); // TODO: GH#18217
+                var baseDeclarationFlags = ts.getDeclarationModifierFlagsFromSymbol(base);
+                ts.Debug.assert(!!derived, "derived should point to something, even if it is the base class' declaration.");
+                if (derived) {
+                    // In order to resolve whether the inherited method was overridden in the base class or not,
+                    // we compare the Symbols obtained. Since getTargetSymbol returns the symbol on the *uninstantiated*
+                    // type declaration, derived and base resolve to the same symbol even in the case of generic classes.
+                    if (derived === base) {
+                        // derived class inherits base without override/redeclaration
+                        var derivedClassDecl = ts.getClassLikeDeclarationOfSymbol(type.symbol);
+                        // It is an error to inherit an abstract member without implementing it or being declared abstract.
+                        // If there is no declaration for the derived class (as in the case of class expressions),
+                        // then the class cannot be declared abstract.
+                        if (baseDeclarationFlags & 128 /* Abstract */ && (!derivedClassDecl || !ts.hasModifier(derivedClassDecl, 128 /* Abstract */))) {
+                            if (derivedClassDecl.kind === 205 /* ClassExpression */) {
+                                error(derivedClassDecl, ts.Diagnostics.Non_abstract_class_expression_does_not_implement_inherited_abstract_member_0_from_class_1, symbolToString(baseProperty), typeToString(baseType));
+                            }
+                            else {
+                                error(derivedClassDecl, ts.Diagnostics.Non_abstract_class_0_does_not_implement_inherited_abstract_member_1_from_class_2, typeToString(type), symbolToString(baseProperty), typeToString(baseType));
+                            }
+                        }
+                    }
+                    else {
+                        // derived overrides base.
+                        var derivedDeclarationFlags = ts.getDeclarationModifierFlagsFromSymbol(derived);
+                        if (baseDeclarationFlags & 8 /* Private */ || derivedDeclarationFlags & 8 /* Private */) {
+                            // either base or derived property is private - not override, skip it
+                            continue;
+                        }
+                        if (isPrototypeProperty(base) || base.flags & 98308 /* PropertyOrAccessor */ && derived.flags & 98308 /* PropertyOrAccessor */) {
+                            // method is overridden with method or property/accessor is overridden with property/accessor - correct case
+                            continue;
+                        }
+                        var errorMessage = void 0;
+                        if (isPrototypeProperty(base)) {
+                            if (derived.flags & 98304 /* Accessor */) {
+                                errorMessage = ts.Diagnostics.Class_0_defines_instance_member_function_1_but_extended_class_2_defines_it_as_instance_member_accessor;
+                            }
+                            else {
+                                errorMessage = ts.Diagnostics.Class_0_defines_instance_member_function_1_but_extended_class_2_defines_it_as_instance_member_property;
+                            }
+                        }
+                        else if (base.flags & 98304 /* Accessor */) {
+                            errorMessage = ts.Diagnostics.Class_0_defines_instance_member_accessor_1_but_extended_class_2_defines_it_as_instance_member_function;
+                        }
+                        else {
+                            errorMessage = ts.Diagnostics.Class_0_defines_instance_member_property_1_but_extended_class_2_defines_it_as_instance_member_function;
+                        }
+                        error(ts.getNameOfDeclaration(derived.valueDeclaration) || derived.valueDeclaration, errorMessage, typeToString(baseType), symbolToString(base), typeToString(type));
+                    }
+                }
+            }
+        }
+        function checkInheritedPropertiesAreIdentical(type, typeNode) {
+            var baseTypes = getBaseTypes(type);
+            if (baseTypes.length < 2) {
+                return true;
+            }
+            var seen = ts.createUnderscoreEscapedMap();
+            ts.forEach(resolveDeclaredMembers(type).declaredProperties, function (p) { seen.set(p.escapedName, { prop: p, containingType: type }); });
+            var ok = true;
+            for (var _i = 0, baseTypes_2 = baseTypes; _i < baseTypes_2.length; _i++) {
+                var base = baseTypes_2[_i];
+                var properties = getPropertiesOfType(getTypeWithThisArgument(base, type.thisType));
+                for (var _a = 0, properties_8 = properties; _a < properties_8.length; _a++) {
+                    var prop = properties_8[_a];
+                    var existing = seen.get(prop.escapedName);
+                    if (!existing) {
+                        seen.set(prop.escapedName, { prop: prop, containingType: base });
+                    }
+                    else {
+                        var isInheritedProperty = existing.containingType !== type;
+                        if (isInheritedProperty && !isPropertyIdenticalTo(existing.prop, prop)) {
+                            ok = false;
+                            var typeName1 = typeToString(existing.containingType);
+                            var typeName2 = typeToString(base);
+                            var errorInfo = ts.chainDiagnosticMessages(/*details*/ undefined, ts.Diagnostics.Named_property_0_of_types_1_and_2_are_not_identical, symbolToString(prop), typeName1, typeName2);
+                            errorInfo = ts.chainDiagnosticMessages(errorInfo, ts.Diagnostics.Interface_0_cannot_simultaneously_extend_types_1_and_2, typeToString(type), typeName1, typeName2);
+                            diagnostics.add(ts.createDiagnosticForNodeFromMessageChain(typeNode, errorInfo));
+                        }
+                    }
+                }
+            }
+            return ok;
+        }
+        function checkPropertyInitialization(node) {
+            if (!strictNullChecks || !strictPropertyInitialization || node.flags & 4194304 /* Ambient */) {
+                return;
+            }
+            var constructor = findConstructorDeclaration(node);
+            for (var _i = 0, _a = node.members; _i < _a.length; _i++) {
+                var member = _a[_i];
+                if (isInstancePropertyWithoutInitializer(member)) {
+                    var propName = member.name;
+                    if (ts.isIdentifier(propName)) {
+                        var type = getTypeOfSymbol(getSymbolOfNode(member));
+                        if (!(type.flags & 3 /* AnyOrUnknown */ || getFalsyFlags(type) & 8192 /* Undefined */)) {
+                            if (!constructor || !isPropertyInitializedInConstructor(propName, type, constructor)) {
+                                error(member.name, ts.Diagnostics.Property_0_has_no_initializer_and_is_not_definitely_assigned_in_the_constructor, ts.declarationNameToString(propName));
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        function isInstancePropertyWithoutInitializer(node) {
+            return node.kind === 152 /* PropertyDeclaration */ &&
+                !ts.hasModifier(node, 32 /* Static */ | 128 /* Abstract */) &&
+                !node.exclamationToken &&
+                !node.initializer;
+        }
+        function isPropertyInitializedInConstructor(propName, propType, constructor) {
+            var reference = ts.createPropertyAccess(ts.createThis(), propName);
+            reference.flowNode = constructor.returnFlowNode;
+            var flowType = getFlowTypeOfReference(reference, propType, getOptionalType(propType));
+            return !(getFalsyFlags(flowType) & 8192 /* Undefined */);
+        }
+        function checkInterfaceDeclaration(node) {
+            // Grammar checking
+            if (!checkGrammarDecoratorsAndModifiers(node))
+                checkGrammarInterfaceDeclaration(node);
+            checkTypeParameters(node.typeParameters);
+            if (produceDiagnostics) {
+                checkTypeNameIsReserved(node.name, ts.Diagnostics.Interface_name_cannot_be_0);
+                checkExportsOnMergedDeclarations(node);
+                var symbol = getSymbolOfNode(node);
+                checkTypeParameterListsIdentical(symbol);
+                // Only check this symbol once
+                var firstInterfaceDecl = ts.getDeclarationOfKind(symbol, 236 /* InterfaceDeclaration */);
+                if (node === firstInterfaceDecl) {
+                    var type = getDeclaredTypeOfSymbol(symbol);
+                    var typeWithThis = getTypeWithThisArgument(type);
+                    // run subsequent checks only if first set succeeded
+                    if (checkInheritedPropertiesAreIdentical(type, node.name)) {
+                        for (var _i = 0, _a = getBaseTypes(type); _i < _a.length; _i++) {
+                            var baseType = _a[_i];
+                            checkTypeAssignableTo(typeWithThis, getTypeWithThisArgument(baseType, type.thisType), node.name, ts.Diagnostics.Interface_0_incorrectly_extends_interface_1);
+                        }
+                        checkIndexConstraints(type);
+                    }
+                }
+                checkObjectTypeForDuplicateDeclarations(node);
+            }
+            ts.forEach(ts.getInterfaceBaseTypeNodes(node), function (heritageElement) {
+                if (!ts.isEntityNameExpression(heritageElement.expression)) {
+                    error(heritageElement.expression, ts.Diagnostics.An_interface_can_only_extend_an_identifier_Slashqualified_name_with_optional_type_arguments);
+                }
+                checkTypeReferenceNode(heritageElement);
+            });
+            ts.forEach(node.members, checkSourceElement);
+            if (produceDiagnostics) {
+                checkTypeForDuplicateIndexSignatures(node);
+                registerForUnusedIdentifiersCheck(node);
+            }
+        }
+        function checkTypeAliasDeclaration(node) {
+            // Grammar checking
+            checkGrammarDecoratorsAndModifiers(node);
+            checkTypeNameIsReserved(node.name, ts.Diagnostics.Type_alias_name_cannot_be_0);
+            checkTypeParameters(node.typeParameters);
+            checkSourceElement(node.type);
+            registerForUnusedIdentifiersCheck(node);
+        }
+        function computeEnumMemberValues(node) {
+            var nodeLinks = getNodeLinks(node);
+            if (!(nodeLinks.flags & 16384 /* EnumValuesComputed */)) {
+                nodeLinks.flags |= 16384 /* EnumValuesComputed */;
+                var autoValue = 0;
+                for (var _i = 0, _a = node.members; _i < _a.length; _i++) {
+                    var member = _a[_i];
+                    var value = computeMemberValue(member, autoValue);
+                    getNodeLinks(member).enumMemberValue = value;
+                    autoValue = typeof value === "number" ? value + 1 : undefined;
+                }
+            }
+        }
+        function computeMemberValue(member, autoValue) {
+            if (isComputedNonLiteralName(member.name)) {
+                error(member.name, ts.Diagnostics.Computed_property_names_are_not_allowed_in_enums);
+            }
+            else {
+                var text = ts.getTextOfPropertyName(member.name);
+                if (isNumericLiteralName(text) && !isInfinityOrNaNString(text)) {
+                    error(member.name, ts.Diagnostics.An_enum_member_cannot_have_a_numeric_name);
+                }
+            }
+            if (member.initializer) {
+                return computeConstantValue(member);
+            }
+            // In ambient enum declarations that specify no const modifier, enum member declarations that omit
+            // a value are considered computed members (as opposed to having auto-incremented values).
+            if (member.parent.flags & 4194304 /* Ambient */ && !ts.isConst(member.parent)) {
+                return undefined;
+            }
+            // If the member declaration specifies no value, the member is considered a constant enum member.
+            // If the member is the first member in the enum declaration, it is assigned the value zero.
+            // Otherwise, it is assigned the value of the immediately preceding member plus one, and an error
+            // occurs if the immediately preceding member is not a constant enum member.
+            if (autoValue !== undefined) {
+                return autoValue;
+            }
+            error(member.name, ts.Diagnostics.Enum_member_must_have_initializer);
+            return undefined;
+        }
+        function computeConstantValue(member) {
+            var enumKind = getEnumKind(getSymbolOfNode(member.parent));
+            var isConstEnum = ts.isConst(member.parent);
+            var initializer = member.initializer;
+            var value = enumKind === 1 /* Literal */ && !isLiteralEnumMember(member) ? undefined : evaluate(initializer);
+            if (value !== undefined) {
+                if (isConstEnum && typeof value === "number" && !isFinite(value)) {
+                    error(initializer, isNaN(value) ?
+                        ts.Diagnostics.const_enum_member_initializer_was_evaluated_to_disallowed_value_NaN :
+                        ts.Diagnostics.const_enum_member_initializer_was_evaluated_to_a_non_finite_value);
+                }
+            }
+            else if (enumKind === 1 /* Literal */) {
+                error(initializer, ts.Diagnostics.Computed_values_are_not_permitted_in_an_enum_with_string_valued_members);
+                return 0;
+            }
+            else if (isConstEnum) {
+                error(initializer, ts.Diagnostics.In_const_enum_declarations_member_initializer_must_be_constant_expression);
+            }
+            else if (member.parent.flags & 4194304 /* Ambient */) {
+                error(initializer, ts.Diagnostics.In_ambient_enum_declarations_member_initializer_must_be_constant_expression);
+            }
+            else {
+                // Only here do we need to check that the initializer is assignable to the enum type.
+                checkTypeAssignableTo(checkExpression(initializer), getDeclaredTypeOfSymbol(getSymbolOfNode(member.parent)), initializer, /*headMessage*/ undefined);
+            }
+            return value;
+            function evaluate(expr) {
+                switch (expr.kind) {
+                    case 198 /* PrefixUnaryExpression */:
+                        var value_2 = evaluate(expr.operand);
+                        if (typeof value_2 === "number") {
+                            switch (expr.operator) {
+                                case 37 /* PlusToken */: return value_2;
+                                case 38 /* MinusToken */: return -value_2;
+                                case 52 /* TildeToken */: return ~value_2;
+                            }
+                        }
+                        break;
+                    case 200 /* BinaryExpression */:
+                        var left = evaluate(expr.left);
+                        var right = evaluate(expr.right);
+                        if (typeof left === "number" && typeof right === "number") {
+                            switch (expr.operatorToken.kind) {
+                                case 49 /* BarToken */: return left | right;
+                                case 48 /* AmpersandToken */: return left & right;
+                                case 46 /* GreaterThanGreaterThanToken */: return left >> right;
+                                case 47 /* GreaterThanGreaterThanGreaterThanToken */: return left >>> right;
+                                case 45 /* LessThanLessThanToken */: return left << right;
+                                case 50 /* CaretToken */: return left ^ right;
+                                case 39 /* AsteriskToken */: return left * right;
+                                case 41 /* SlashToken */: return left / right;
+                                case 37 /* PlusToken */: return left + right;
+                                case 38 /* MinusToken */: return left - right;
+                                case 42 /* PercentToken */: return left % right;
+                                case 40 /* AsteriskAsteriskToken */: return Math.pow(left, right);
+                            }
+                        }
+                        else if (typeof left === "string" && typeof right === "string" && expr.operatorToken.kind === 37 /* PlusToken */) {
+                            return left + right;
+                        }
+                        break;
+                    case 9 /* StringLiteral */:
+                        return expr.text;
+                    case 8 /* NumericLiteral */:
+                        checkGrammarNumericLiteral(expr);
+                        return +expr.text;
+                    case 191 /* ParenthesizedExpression */:
+                        return evaluate(expr.expression);
+                    case 71 /* Identifier */:
+                        var identifier = expr;
+                        if (isInfinityOrNaNString(identifier.escapedText)) {
+                            return +(identifier.escapedText);
+                        }
+                        return ts.nodeIsMissing(expr) ? 0 : evaluateEnumMember(expr, getSymbolOfNode(member.parent), identifier.escapedText);
+                    case 186 /* ElementAccessExpression */:
+                    case 185 /* PropertyAccessExpression */:
+                        var ex = expr;
+                        if (isConstantMemberAccess(ex)) {
+                            var type = getTypeOfExpression(ex.expression);
+                            if (type.symbol && type.symbol.flags & 384 /* Enum */) {
+                                var name = void 0;
+                                if (ex.kind === 185 /* PropertyAccessExpression */) {
+                                    name = ex.name.escapedText;
+                                }
+                                else {
+                                    var argument = ex.argumentExpression;
+                                    ts.Debug.assert(ts.isLiteralExpression(argument));
+                                    name = ts.escapeLeadingUnderscores(argument.text);
+                                }
+                                return evaluateEnumMember(expr, type.symbol, name);
+                            }
+                        }
+                        break;
+                }
+                return undefined;
+            }
+            function evaluateEnumMember(expr, enumSymbol, name) {
+                var memberSymbol = enumSymbol.exports.get(name);
+                if (memberSymbol) {
+                    var declaration = memberSymbol.valueDeclaration;
+                    if (declaration !== member) {
+                        if (isBlockScopedNameDeclaredBeforeUse(declaration, member)) {
+                            return getEnumMemberValue(declaration);
+                        }
+                        error(expr, ts.Diagnostics.A_member_initializer_in_a_enum_declaration_cannot_reference_members_declared_after_it_including_members_defined_in_other_enums);
+                        return 0;
+                    }
+                }
+                return undefined;
+            }
+        }
+        function isConstantMemberAccess(node) {
+            return node.kind === 71 /* Identifier */ ||
+                node.kind === 185 /* PropertyAccessExpression */ && isConstantMemberAccess(node.expression) ||
+                node.kind === 186 /* ElementAccessExpression */ && isConstantMemberAccess(node.expression) &&
+                    node.argumentExpression.kind === 9 /* StringLiteral */;
+        }
+        function checkEnumDeclaration(node) {
+            if (!produceDiagnostics) {
+                return;
+            }
+            // Grammar checking
+            checkGrammarDecoratorsAndModifiers(node);
+            checkTypeNameIsReserved(node.name, ts.Diagnostics.Enum_name_cannot_be_0);
+            checkCollisionWithRequireExportsInGeneratedCode(node, node.name);
+            checkCollisionWithGlobalPromiseInGeneratedCode(node, node.name);
+            checkExportsOnMergedDeclarations(node);
+            computeEnumMemberValues(node);
+            var enumIsConst = ts.isConst(node);
+            if (compilerOptions.isolatedModules && enumIsConst && node.flags & 4194304 /* Ambient */) {
+                error(node.name, ts.Diagnostics.Ambient_const_enums_are_not_allowed_when_the_isolatedModules_flag_is_provided);
+            }
+            // Spec 2014 - Section 9.3:
+            // It isn't possible for one enum declaration to continue the automatic numbering sequence of another,
+            // and when an enum type has multiple declarations, only one declaration is permitted to omit a value
+            // for the first member.
+            //
+            // Only perform this check once per symbol
+            var enumSymbol = getSymbolOfNode(node);
+            var firstDeclaration = ts.getDeclarationOfKind(enumSymbol, node.kind);
+            if (node === firstDeclaration) {
+                if (enumSymbol.declarations.length > 1) {
+                    // check that const is placed\omitted on all enum declarations
+                    ts.forEach(enumSymbol.declarations, function (decl) {
+                        if (ts.isConstEnumDeclaration(decl) !== enumIsConst) {
+                            error(ts.getNameOfDeclaration(decl), ts.Diagnostics.Enum_declarations_must_all_be_const_or_non_const);
+                        }
+                    });
+                }
+                var seenEnumMissingInitialInitializer_1 = false;
+                ts.forEach(enumSymbol.declarations, function (declaration) {
+                    // return true if we hit a violation of the rule, false otherwise
+                    if (declaration.kind !== 238 /* EnumDeclaration */) {
+                        return false;
+                    }
+                    var enumDeclaration = declaration;
+                    if (!enumDeclaration.members.length) {
+                        return false;
+                    }
+                    var firstEnumMember = enumDeclaration.members[0];
+                    if (!firstEnumMember.initializer) {
+                        if (seenEnumMissingInitialInitializer_1) {
+                            error(firstEnumMember.name, ts.Diagnostics.In_an_enum_with_multiple_declarations_only_one_declaration_can_omit_an_initializer_for_its_first_enum_element);
+                        }
+                        else {
+                            seenEnumMissingInitialInitializer_1 = true;
+                        }
+                    }
+                });
+            }
+        }
+        function getFirstNonAmbientClassOrFunctionDeclaration(symbol) {
+            var declarations = symbol.declarations;
+            for (var _i = 0, declarations_8 = declarations; _i < declarations_8.length; _i++) {
+                var declaration = declarations_8[_i];
+                if ((declaration.kind === 235 /* ClassDeclaration */ ||
+                    (declaration.kind === 234 /* FunctionDeclaration */ && ts.nodeIsPresent(declaration.body))) &&
+                    !(declaration.flags & 4194304 /* Ambient */)) {
+                    return declaration;
+                }
+            }
+            return undefined;
+        }
+        function inSameLexicalScope(node1, node2) {
+            var container1 = ts.getEnclosingBlockScopeContainer(node1);
+            var container2 = ts.getEnclosingBlockScopeContainer(node2);
+            if (isGlobalSourceFile(container1)) {
+                return isGlobalSourceFile(container2);
+            }
+            else if (isGlobalSourceFile(container2)) {
+                return false;
+            }
+            else {
+                return container1 === container2;
+            }
+        }
+        function checkModuleDeclaration(node) {
+            if (produceDiagnostics) {
+                // Grammar checking
+                var isGlobalAugmentation = ts.isGlobalScopeAugmentation(node);
+                var inAmbientContext = node.flags & 4194304 /* Ambient */;
+                if (isGlobalAugmentation && !inAmbientContext) {
+                    error(node.name, ts.Diagnostics.Augmentations_for_the_global_scope_should_have_declare_modifier_unless_they_appear_in_already_ambient_context);
+                }
+                var isAmbientExternalModule = ts.isAmbientModule(node);
+                var contextErrorMessage = isAmbientExternalModule
+                    ? ts.Diagnostics.An_ambient_module_declaration_is_only_allowed_at_the_top_level_in_a_file
+                    : ts.Diagnostics.A_namespace_declaration_is_only_allowed_in_a_namespace_or_module;
+                if (checkGrammarModuleElementContext(node, contextErrorMessage)) {
+                    // If we hit a module declaration in an illegal context, just bail out to avoid cascading errors.
+                    return;
+                }
+                if (!checkGrammarDecoratorsAndModifiers(node)) {
+                    if (!inAmbientContext && node.name.kind === 9 /* StringLiteral */) {
+                        grammarErrorOnNode(node.name, ts.Diagnostics.Only_ambient_modules_can_use_quoted_names);
+                    }
+                }
+                if (ts.isIdentifier(node.name)) {
+                    checkCollisionWithRequireExportsInGeneratedCode(node, node.name);
+                    checkCollisionWithGlobalPromiseInGeneratedCode(node, node.name);
+                }
+                checkExportsOnMergedDeclarations(node);
+                var symbol = getSymbolOfNode(node);
+                // The following checks only apply on a non-ambient instantiated module declaration.
+                if (symbol.flags & 512 /* ValueModule */
+                    && symbol.declarations.length > 1
+                    && !inAmbientContext
+                    && isInstantiatedModule(node, !!compilerOptions.preserveConstEnums || !!compilerOptions.isolatedModules)) {
+                    var firstNonAmbientClassOrFunc = getFirstNonAmbientClassOrFunctionDeclaration(symbol);
+                    if (firstNonAmbientClassOrFunc) {
+                        if (ts.getSourceFileOfNode(node) !== ts.getSourceFileOfNode(firstNonAmbientClassOrFunc)) {
+                            error(node.name, ts.Diagnostics.A_namespace_declaration_cannot_be_in_a_different_file_from_a_class_or_function_with_which_it_is_merged);
+                        }
+                        else if (node.pos < firstNonAmbientClassOrFunc.pos) {
+                            error(node.name, ts.Diagnostics.A_namespace_declaration_cannot_be_located_prior_to_a_class_or_function_with_which_it_is_merged);
+                        }
+                    }
+                    // if the module merges with a class declaration in the same lexical scope,
+                    // we need to track this to ensure the correct emit.
+                    var mergedClass = ts.getDeclarationOfKind(symbol, 235 /* ClassDeclaration */);
+                    if (mergedClass &&
+                        inSameLexicalScope(node, mergedClass)) {
+                        getNodeLinks(node).flags |= 32768 /* LexicalModuleMergesWithClass */;
+                    }
+                }
+                if (isAmbientExternalModule) {
+                    if (ts.isExternalModuleAugmentation(node)) {
+                        // body of the augmentation should be checked for consistency only if augmentation was applied to its target (either global scope or module)
+                        // otherwise we'll be swamped in cascading errors.
+                        // We can detect if augmentation was applied using following rules:
+                        // - augmentation for a global scope is always applied
+                        // - augmentation for some external module is applied if symbol for augmentation is merged (it was combined with target module).
+                        var checkBody = isGlobalAugmentation || (getSymbolOfNode(node).flags & 33554432 /* Transient */);
+                        if (checkBody && node.body) {
+                            for (var _i = 0, _a = node.body.statements; _i < _a.length; _i++) {
+                                var statement = _a[_i];
+                                checkModuleAugmentationElement(statement, isGlobalAugmentation);
+                            }
+                        }
+                    }
+                    else if (isGlobalSourceFile(node.parent)) {
+                        if (isGlobalAugmentation) {
+                            error(node.name, ts.Diagnostics.Augmentations_for_the_global_scope_can_only_be_directly_nested_in_external_modules_or_ambient_module_declarations);
+                        }
+                        else if (ts.isExternalModuleNameRelative(ts.getTextOfIdentifierOrLiteral(node.name))) {
+                            error(node.name, ts.Diagnostics.Ambient_module_declaration_cannot_specify_relative_module_name);
+                        }
+                    }
+                    else {
+                        if (isGlobalAugmentation) {
+                            error(node.name, ts.Diagnostics.Augmentations_for_the_global_scope_can_only_be_directly_nested_in_external_modules_or_ambient_module_declarations);
+                        }
+                        else {
+                            // Node is not an augmentation and is not located on the script level.
+                            // This means that this is declaration of ambient module that is located in other module or namespace which is prohibited.
+                            error(node.name, ts.Diagnostics.Ambient_modules_cannot_be_nested_in_other_modules_or_namespaces);
+                        }
+                    }
+                }
+            }
+            if (node.body) {
+                checkSourceElement(node.body);
+                if (!ts.isGlobalScopeAugmentation(node)) {
+                    registerForUnusedIdentifiersCheck(node);
+                }
+            }
+        }
+        function checkModuleAugmentationElement(node, isGlobalAugmentation) {
+            switch (node.kind) {
+                case 214 /* VariableStatement */:
+                    // error each individual name in variable statement instead of marking the entire variable statement
+                    for (var _i = 0, _a = node.declarationList.declarations; _i < _a.length; _i++) {
+                        var decl = _a[_i];
+                        checkModuleAugmentationElement(decl, isGlobalAugmentation);
+                    }
+                    break;
+                case 249 /* ExportAssignment */:
+                case 250 /* ExportDeclaration */:
+                    grammarErrorOnFirstToken(node, ts.Diagnostics.Exports_and_export_assignments_are_not_permitted_in_module_augmentations);
+                    break;
+                case 243 /* ImportEqualsDeclaration */:
+                case 244 /* ImportDeclaration */:
+                    grammarErrorOnFirstToken(node, ts.Diagnostics.Imports_are_not_permitted_in_module_augmentations_Consider_moving_them_to_the_enclosing_external_module);
+                    break;
+                case 182 /* BindingElement */:
+                case 232 /* VariableDeclaration */:
+                    var name = node.name;
+                    if (ts.isBindingPattern(name)) {
+                        for (var _b = 0, _c = name.elements; _b < _c.length; _b++) {
+                            var el = _c[_b];
+                            // mark individual names in binding pattern
+                            checkModuleAugmentationElement(el, isGlobalAugmentation);
+                        }
+                        break;
+                    }
+                // falls through
+                case 235 /* ClassDeclaration */:
+                case 238 /* EnumDeclaration */:
+                case 234 /* FunctionDeclaration */:
+                case 236 /* InterfaceDeclaration */:
+                case 239 /* ModuleDeclaration */:
+                case 237 /* TypeAliasDeclaration */:
+                    if (isGlobalAugmentation) {
+                        return;
+                    }
+                    var symbol = getSymbolOfNode(node);
+                    if (symbol) {
+                        // module augmentations cannot introduce new names on the top level scope of the module
+                        // this is done it two steps
+                        // 1. quick check - if symbol for node is not merged - this is local symbol to this augmentation - report error
+                        // 2. main check - report error if value declaration of the parent symbol is module augmentation)
+                        var reportError = !(symbol.flags & 33554432 /* Transient */);
+                        if (!reportError) {
+                            // symbol should not originate in augmentation
+                            reportError = ts.isExternalModuleAugmentation(symbol.parent.declarations[0]);
+                        }
+                    }
+                    break;
+            }
+        }
+        function getFirstIdentifier(node) {
+            switch (node.kind) {
+                case 71 /* Identifier */:
+                    return node;
+                case 146 /* QualifiedName */:
+                    do {
+                        node = node.left;
+                    } while (node.kind !== 71 /* Identifier */);
+                    return node;
+                case 185 /* PropertyAccessExpression */:
+                    do {
+                        node = node.expression;
+                    } while (node.kind !== 71 /* Identifier */);
+                    return node;
+            }
+        }
+        function checkExternalImportOrExportDeclaration(node) {
+            var moduleName = ts.getExternalModuleName(node);
+            if (!moduleName || ts.nodeIsMissing(moduleName)) {
+                // Should be a parse error.
+                return false;
+            }
+            if (!ts.isStringLiteral(moduleName)) {
+                error(moduleName, ts.Diagnostics.String_literal_expected);
+                return false;
+            }
+            var inAmbientExternalModule = node.parent.kind === 240 /* ModuleBlock */ && ts.isAmbientModule(node.parent.parent);
+            if (node.parent.kind !== 274 /* SourceFile */ && !inAmbientExternalModule) {
+                error(moduleName, node.kind === 250 /* ExportDeclaration */ ?
+                    ts.Diagnostics.Export_declarations_are_not_permitted_in_a_namespace :
+                    ts.Diagnostics.Import_declarations_in_a_namespace_cannot_reference_a_module);
+                return false;
+            }
+            if (inAmbientExternalModule && ts.isExternalModuleNameRelative(moduleName.text)) {
+                // we have already reported errors on top level imports\exports in external module augmentations in checkModuleDeclaration
+                // no need to do this again.
+                if (!isTopLevelInExternalModuleAugmentation(node)) {
+                    // TypeScript 1.0 spec (April 2013): 12.1.6
+                    // An ExternalImportDeclaration in an AmbientExternalModuleDeclaration may reference
+                    // other external modules only through top - level external module names.
+                    // Relative external module names are not permitted.
+                    error(node, ts.Diagnostics.Import_or_export_declaration_in_an_ambient_module_declaration_cannot_reference_module_through_relative_module_name);
+                    return false;
+                }
+            }
+            return true;
+        }
+        function checkAliasSymbol(node) {
+            var symbol = getSymbolOfNode(node);
+            var target = resolveAlias(symbol);
+            if (target !== unknownSymbol) {
+                // For external modules symbol represent local symbol for an alias.
+                // This local symbol will merge any other local declarations (excluding other aliases)
+                // and symbol.flags will contains combined representation for all merged declaration.
+                // Based on symbol.flags we can compute a set of excluded meanings (meaning that resolved alias should not have,
+                // otherwise it will conflict with some local declaration). Note that in addition to normal flags we include matching SymbolFlags.Export*
+                // in order to prevent collisions with declarations that were exported from the current module (they still contribute to local names).
+                var excludedMeanings = (symbol.flags & (67216319 /* Value */ | 1048576 /* ExportValue */) ? 67216319 /* Value */ : 0) |
+                    (symbol.flags & 67901928 /* Type */ ? 67901928 /* Type */ : 0) |
+                    (symbol.flags & 1920 /* Namespace */ ? 1920 /* Namespace */ : 0);
+                if (target.flags & excludedMeanings) {
+                    var message = node.kind === 252 /* ExportSpecifier */ ?
+                        ts.Diagnostics.Export_declaration_conflicts_with_exported_declaration_of_0 :
+                        ts.Diagnostics.Import_declaration_conflicts_with_local_declaration_of_0;
+                    error(node, message, symbolToString(symbol));
+                }
+                // Don't allow to re-export something with no value side when `--isolatedModules` is set.
+                if (compilerOptions.isolatedModules
+                    && node.kind === 252 /* ExportSpecifier */
+                    && !(target.flags & 67216319 /* Value */)
+                    && !(node.flags & 4194304 /* Ambient */)) {
+                    error(node, ts.Diagnostics.Cannot_re_export_a_type_when_the_isolatedModules_flag_is_provided);
+                }
+            }
+        }
+        function checkImportBinding(node) {
+            checkCollisionWithRequireExportsInGeneratedCode(node, node.name);
+            checkCollisionWithGlobalPromiseInGeneratedCode(node, node.name);
+            checkAliasSymbol(node);
+        }
+        function checkImportDeclaration(node) {
+            if (checkGrammarModuleElementContext(node, ts.Diagnostics.An_import_declaration_can_only_be_used_in_a_namespace_or_module)) {
+                // If we hit an import declaration in an illegal context, just bail out to avoid cascading errors.
+                return;
+            }
+            if (!checkGrammarDecoratorsAndModifiers(node) && ts.hasModifiers(node)) {
+                grammarErrorOnFirstToken(node, ts.Diagnostics.An_import_declaration_cannot_have_modifiers);
+            }
+            if (checkExternalImportOrExportDeclaration(node)) {
+                var importClause = node.importClause;
+                if (importClause) {
+                    if (importClause.name) {
+                        checkImportBinding(importClause);
+                    }
+                    if (importClause.namedBindings) {
+                        if (importClause.namedBindings.kind === 246 /* NamespaceImport */) {
+                            checkImportBinding(importClause.namedBindings);
+                        }
+                        else {
+                            var moduleExisted = resolveExternalModuleName(node, node.moduleSpecifier);
+                            if (moduleExisted) {
+                                ts.forEach(importClause.namedBindings.elements, checkImportBinding);
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        function checkImportEqualsDeclaration(node) {
+            if (checkGrammarModuleElementContext(node, ts.Diagnostics.An_import_declaration_can_only_be_used_in_a_namespace_or_module)) {
+                // If we hit an import declaration in an illegal context, just bail out to avoid cascading errors.
+                return;
+            }
+            checkGrammarDecoratorsAndModifiers(node);
+            if (ts.isInternalModuleImportEqualsDeclaration(node) || checkExternalImportOrExportDeclaration(node)) {
+                checkImportBinding(node);
+                if (ts.hasModifier(node, 1 /* Export */)) {
+                    markExportAsReferenced(node);
+                }
+                if (node.moduleReference.kind !== 254 /* ExternalModuleReference */) {
+                    var target = resolveAlias(getSymbolOfNode(node));
+                    if (target !== unknownSymbol) {
+                        if (target.flags & 67216319 /* Value */) {
+                            // Target is a value symbol, check that it is not hidden by a local declaration with the same name
+                            var moduleName = getFirstIdentifier(node.moduleReference);
+                            if (!(resolveEntityName(moduleName, 67216319 /* Value */ | 1920 /* Namespace */).flags & 1920 /* Namespace */)) {
+                                error(moduleName, ts.Diagnostics.Module_0_is_hidden_by_a_local_declaration_with_the_same_name, ts.declarationNameToString(moduleName));
+                            }
+                        }
+                        if (target.flags & 67901928 /* Type */) {
+                            checkTypeNameIsReserved(node.name, ts.Diagnostics.Import_name_cannot_be_0);
+                        }
+                    }
+                }
+                else {
+                    if (moduleKind >= ts.ModuleKind.ES2015 && !(node.flags & 4194304 /* Ambient */)) {
+                        // Import equals declaration is deprecated in es6 or above
+                        grammarErrorOnNode(node, ts.Diagnostics.Import_assignment_cannot_be_used_when_targeting_ECMAScript_modules_Consider_using_import_Asterisk_as_ns_from_mod_import_a_from_mod_import_d_from_mod_or_another_module_format_instead);
+                    }
+                }
+            }
+        }
+        function checkExportDeclaration(node) {
+            if (checkGrammarModuleElementContext(node, ts.Diagnostics.An_export_declaration_can_only_be_used_in_a_module)) {
+                // If we hit an export in an illegal context, just bail out to avoid cascading errors.
+                return;
+            }
+            if (!checkGrammarDecoratorsAndModifiers(node) && ts.hasModifiers(node)) {
+                grammarErrorOnFirstToken(node, ts.Diagnostics.An_export_declaration_cannot_have_modifiers);
+            }
+            if (!node.moduleSpecifier || checkExternalImportOrExportDeclaration(node)) {
+                if (node.exportClause) {
+                    // export { x, y }
+                    // export { x, y } from "foo"
+                    ts.forEach(node.exportClause.elements, checkExportSpecifier);
+                    var inAmbientExternalModule = node.parent.kind === 240 /* ModuleBlock */ && ts.isAmbientModule(node.parent.parent);
+                    var inAmbientNamespaceDeclaration = !inAmbientExternalModule && node.parent.kind === 240 /* ModuleBlock */ &&
+                        !node.moduleSpecifier && node.flags & 4194304 /* Ambient */;
+                    if (node.parent.kind !== 274 /* SourceFile */ && !inAmbientExternalModule && !inAmbientNamespaceDeclaration) {
+                        error(node, ts.Diagnostics.Export_declarations_are_not_permitted_in_a_namespace);
+                    }
+                }
+                else {
+                    // export * from "foo"
+                    var moduleSymbol_2 = resolveExternalModuleName(node, node.moduleSpecifier);
+                    if (moduleSymbol_2 && hasExportAssignmentSymbol(moduleSymbol_2)) {
+                        error(node.moduleSpecifier, ts.Diagnostics.Module_0_uses_export_and_cannot_be_used_with_export_Asterisk, symbolToString(moduleSymbol_2));
+                    }
+                    if (moduleKind !== ts.ModuleKind.System && moduleKind !== ts.ModuleKind.ES2015 && moduleKind !== ts.ModuleKind.ESNext) {
+                        checkExternalEmitHelpers(node, 32768 /* ExportStar */);
+                    }
+                }
+            }
+        }
+        function checkGrammarModuleElementContext(node, errorMessage) {
+            var isInAppropriateContext = node.parent.kind === 274 /* SourceFile */ || node.parent.kind === 240 /* ModuleBlock */ || node.parent.kind === 239 /* ModuleDeclaration */;
+            if (!isInAppropriateContext) {
+                grammarErrorOnFirstToken(node, errorMessage);
+            }
+            return !isInAppropriateContext;
+        }
+        function checkExportSpecifier(node) {
+            checkAliasSymbol(node);
+            if (compilerOptions.declaration) {
+                collectLinkedAliases(node.propertyName || node.name, /*setVisibility*/ true);
+            }
+            if (!node.parent.parent.moduleSpecifier) {
+                var exportedName = node.propertyName || node.name;
+                // find immediate value referenced by exported name (SymbolFlags.Alias is set so we don't chase down aliases)
+                var symbol = resolveName(exportedName, exportedName.escapedText, 67216319 /* Value */ | 67901928 /* Type */ | 1920 /* Namespace */ | 2097152 /* Alias */, 
+                /*nameNotFoundMessage*/ undefined, /*nameArg*/ undefined, /*isUse*/ true);
+                if (symbol && (symbol === undefinedSymbol || isGlobalSourceFile(getDeclarationContainer(symbol.declarations[0])))) {
+                    error(exportedName, ts.Diagnostics.Cannot_export_0_Only_local_declarations_can_be_exported_from_a_module, ts.idText(exportedName));
+                }
+                else {
+                    markExportAsReferenced(node);
+                }
+            }
+        }
+        function checkExportAssignment(node) {
+            if (checkGrammarModuleElementContext(node, ts.Diagnostics.An_export_assignment_can_only_be_used_in_a_module)) {
+                // If we hit an export assignment in an illegal context, just bail out to avoid cascading errors.
+                return;
+            }
+            var container = node.parent.kind === 274 /* SourceFile */ ? node.parent : node.parent.parent;
+            if (container.kind === 239 /* ModuleDeclaration */ && !ts.isAmbientModule(container)) {
+                if (node.isExportEquals) {
+                    error(node, ts.Diagnostics.An_export_assignment_cannot_be_used_in_a_namespace);
+                }
+                else {
+                    error(node, ts.Diagnostics.A_default_export_can_only_be_used_in_an_ECMAScript_style_module);
+                }
+                return;
+            }
+            // Grammar checking
+            if (!checkGrammarDecoratorsAndModifiers(node) && ts.hasModifiers(node)) {
+                grammarErrorOnFirstToken(node, ts.Diagnostics.An_export_assignment_cannot_have_modifiers);
+            }
+            if (node.expression.kind === 71 /* Identifier */) {
+                markExportAsReferenced(node);
+                if (compilerOptions.declaration) {
+                    collectLinkedAliases(node.expression, /*setVisibility*/ true);
+                }
+            }
+            else {
+                checkExpressionCached(node.expression);
+            }
+            checkExternalModuleExports(container);
+            if ((node.flags & 4194304 /* Ambient */) && !ts.isEntityNameExpression(node.expression)) {
+                grammarErrorOnNode(node.expression, ts.Diagnostics.The_expression_of_an_export_assignment_must_be_an_identifier_or_qualified_name_in_an_ambient_context);
+            }
+            if (node.isExportEquals && !(node.flags & 4194304 /* Ambient */)) {
+                if (moduleKind >= ts.ModuleKind.ES2015) {
+                    // export assignment is not supported in es6 modules
+                    grammarErrorOnNode(node, ts.Diagnostics.Export_assignment_cannot_be_used_when_targeting_ECMAScript_modules_Consider_using_export_default_or_another_module_format_instead);
+                }
+                else if (moduleKind === ts.ModuleKind.System) {
+                    // system modules does not support export assignment
+                    grammarErrorOnNode(node, ts.Diagnostics.Export_assignment_is_not_supported_when_module_flag_is_system);
+                }
+            }
+        }
+        function hasExportedMembers(moduleSymbol) {
+            return ts.forEachEntry(moduleSymbol.exports, function (_, id) { return id !== "export="; });
+        }
+        function checkExternalModuleExports(node) {
+            var moduleSymbol = getSymbolOfNode(node);
+            var links = getSymbolLinks(moduleSymbol);
+            if (!links.exportsChecked) {
+                var exportEqualsSymbol = moduleSymbol.exports.get("export=");
+                if (exportEqualsSymbol && hasExportedMembers(moduleSymbol)) {
+                    var declaration = getDeclarationOfAliasSymbol(exportEqualsSymbol) || exportEqualsSymbol.valueDeclaration;
+                    if (!isTopLevelInExternalModuleAugmentation(declaration) && !ts.isInJavaScriptFile(declaration)) {
+                        error(declaration, ts.Diagnostics.An_export_assignment_cannot_be_used_in_a_module_with_other_exported_elements);
+                    }
+                }
+                // Checks for export * conflicts
+                var exports_1 = getExportsOfModule(moduleSymbol);
+                if (exports_1) {
+                    exports_1.forEach(function (_a, id) {
+                        var declarations = _a.declarations, flags = _a.flags;
+                        if (id === "__export") {
+                            return;
+                        }
+                        // ECMA262: 15.2.1.1 It is a Syntax Error if the ExportedNames of ModuleItemList contains any duplicate entries.
+                        // (TS Exceptions: namespaces, function overloads, enums, and interfaces)
+                        if (flags & (1920 /* Namespace */ | 64 /* Interface */ | 384 /* Enum */)) {
+                            return;
+                        }
+                        var exportedDeclarationsCount = ts.countWhere(declarations, isNotOverloadAndNotAccessor);
+                        if (flags & 524288 /* TypeAlias */ && exportedDeclarationsCount <= 2) {
+                            // it is legal to merge type alias with other values
+                            // so count should be either 1 (just type alias) or 2 (type alias + merged value)
+                            return;
+                        }
+                        if (exportedDeclarationsCount > 1) {
+                            for (var _i = 0, declarations_9 = declarations; _i < declarations_9.length; _i++) {
+                                var declaration = declarations_9[_i];
+                                if (isNotOverload(declaration)) {
+                                    diagnostics.add(ts.createDiagnosticForNode(declaration, ts.Diagnostics.Cannot_redeclare_exported_variable_0, ts.unescapeLeadingUnderscores(id)));
+                                }
+                            }
+                        }
+                    });
+                }
+                links.exportsChecked = true;
+            }
+        }
+        function isNotAccessor(declaration) {
+            // Accessors check for their own matching duplicates, and in contexts where they are valid, there are already duplicate identifier checks
+            return !ts.isAccessor(declaration);
+        }
+        function isNotOverload(declaration) {
+            return (declaration.kind !== 234 /* FunctionDeclaration */ && declaration.kind !== 154 /* MethodDeclaration */) ||
+                !!declaration.body;
+        }
+        function checkSourceElement(node) {
+            if (!node) {
+                return;
+            }
+            if (ts.isInJavaScriptFile(node)) {
+                ts.forEach(node.jsDoc, function (_a) {
+                    var tags = _a.tags;
+                    return ts.forEach(tags, checkSourceElement);
+                });
+            }
+            var kind = node.kind;
+            if (cancellationToken) {
+                // Only bother checking on a few construct kinds.  We don't want to be excessively
+                // hitting the cancellation token on every node we check.
+                switch (kind) {
+                    case 239 /* ModuleDeclaration */:
+                    case 235 /* ClassDeclaration */:
+                    case 236 /* InterfaceDeclaration */:
+                    case 234 /* FunctionDeclaration */:
+                        cancellationToken.throwIfCancellationRequested();
+                }
+            }
+            switch (kind) {
+                case 148 /* TypeParameter */:
+                    return checkTypeParameter(node);
+                case 149 /* Parameter */:
+                    return checkParameter(node);
+                case 152 /* PropertyDeclaration */:
+                case 151 /* PropertySignature */:
+                    return checkPropertyDeclaration(node);
+                case 163 /* FunctionType */:
+                case 164 /* ConstructorType */:
+                case 158 /* CallSignature */:
+                case 159 /* ConstructSignature */:
+                case 160 /* IndexSignature */:
+                    return checkSignatureDeclaration(node);
+                case 154 /* MethodDeclaration */:
+                case 153 /* MethodSignature */:
+                    return checkMethodDeclaration(node);
+                case 155 /* Constructor */:
+                    return checkConstructorDeclaration(node);
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                    return checkAccessorDeclaration(node);
+                case 162 /* TypeReference */:
+                    return checkTypeReferenceNode(node);
+                case 161 /* TypePredicate */:
+                    return checkTypePredicate(node);
+                case 165 /* TypeQuery */:
+                    return checkTypeQuery(node);
+                case 166 /* TypeLiteral */:
+                    return checkTypeLiteral(node);
+                case 167 /* ArrayType */:
+                    return checkArrayType(node);
+                case 168 /* TupleType */:
+                    return checkTupleType(node);
+                case 169 /* UnionType */:
+                case 170 /* IntersectionType */:
+                    return checkUnionOrIntersectionType(node);
+                case 173 /* ParenthesizedType */:
+                    return checkSourceElement(node.type);
+                case 175 /* TypeOperator */:
+                    return checkTypeOperator(node);
+                case 171 /* ConditionalType */:
+                    return checkConditionalType(node);
+                case 172 /* InferType */:
+                    return checkInferType(node);
+                case 179 /* ImportType */:
+                    return checkImportType(node);
+                case 290 /* JSDocAugmentsTag */:
+                    return checkJSDocAugmentsTag(node);
+                case 297 /* JSDocTypedefTag */:
+                case 292 /* JSDocCallbackTag */:
+                    return checkJSDocTypeAliasTag(node);
+                case 293 /* JSDocParameterTag */:
+                    return checkJSDocParameterTag(node);
+                case 284 /* JSDocFunctionType */:
+                    checkSignatureDeclaration(node);
+                // falls through
+                case 282 /* JSDocNonNullableType */:
+                case 281 /* JSDocNullableType */:
+                case 279 /* JSDocAllType */:
+                case 280 /* JSDocUnknownType */:
+                case 287 /* JSDocTypeLiteral */:
+                    checkJSDocTypeIsInJsFile(node);
+                    ts.forEachChild(node, checkSourceElement);
+                    return;
+                case 285 /* JSDocVariadicType */:
+                    checkJSDocVariadicType(node);
+                    return;
+                case 278 /* JSDocTypeExpression */:
+                    return checkSourceElement(node.type);
+                case 176 /* IndexedAccessType */:
+                    return checkIndexedAccessType(node);
+                case 177 /* MappedType */:
+                    return checkMappedType(node);
+                case 234 /* FunctionDeclaration */:
+                    return checkFunctionDeclaration(node);
+                case 213 /* Block */:
+                case 240 /* ModuleBlock */:
+                    return checkBlock(node);
+                case 214 /* VariableStatement */:
+                    return checkVariableStatement(node);
+                case 216 /* ExpressionStatement */:
+                    return checkExpressionStatement(node);
+                case 217 /* IfStatement */:
+                    return checkIfStatement(node);
+                case 218 /* DoStatement */:
+                    return checkDoStatement(node);
+                case 219 /* WhileStatement */:
+                    return checkWhileStatement(node);
+                case 220 /* ForStatement */:
+                    return checkForStatement(node);
+                case 221 /* ForInStatement */:
+                    return checkForInStatement(node);
+                case 222 /* ForOfStatement */:
+                    return checkForOfStatement(node);
+                case 223 /* ContinueStatement */:
+                case 224 /* BreakStatement */:
+                    return checkBreakOrContinueStatement(node);
+                case 225 /* ReturnStatement */:
+                    return checkReturnStatement(node);
+                case 226 /* WithStatement */:
+                    return checkWithStatement(node);
+                case 227 /* SwitchStatement */:
+                    return checkSwitchStatement(node);
+                case 228 /* LabeledStatement */:
+                    return checkLabeledStatement(node);
+                case 229 /* ThrowStatement */:
+                    return checkThrowStatement(node);
+                case 230 /* TryStatement */:
+                    return checkTryStatement(node);
+                case 232 /* VariableDeclaration */:
+                    return checkVariableDeclaration(node);
+                case 182 /* BindingElement */:
+                    return checkBindingElement(node);
+                case 235 /* ClassDeclaration */:
+                    return checkClassDeclaration(node);
+                case 236 /* InterfaceDeclaration */:
+                    return checkInterfaceDeclaration(node);
+                case 237 /* TypeAliasDeclaration */:
+                    return checkTypeAliasDeclaration(node);
+                case 238 /* EnumDeclaration */:
+                    return checkEnumDeclaration(node);
+                case 239 /* ModuleDeclaration */:
+                    return checkModuleDeclaration(node);
+                case 244 /* ImportDeclaration */:
+                    return checkImportDeclaration(node);
+                case 243 /* ImportEqualsDeclaration */:
+                    return checkImportEqualsDeclaration(node);
+                case 250 /* ExportDeclaration */:
+                    return checkExportDeclaration(node);
+                case 249 /* ExportAssignment */:
+                    return checkExportAssignment(node);
+                case 215 /* EmptyStatement */:
+                case 231 /* DebuggerStatement */:
+                    checkGrammarStatementInAmbientContext(node);
+                    return;
+                case 253 /* MissingDeclaration */:
+                    return checkMissingDeclaration(node);
+            }
+        }
+        function checkJSDocTypeIsInJsFile(node) {
+            if (!ts.isInJavaScriptFile(node)) {
+                grammarErrorOnNode(node, ts.Diagnostics.JSDoc_types_can_only_be_used_inside_documentation_comments);
+            }
+        }
+        function checkJSDocVariadicType(node) {
+            checkJSDocTypeIsInJsFile(node);
+            checkSourceElement(node.type);
+            // Only legal location is in the *last* parameter tag or last parameter of a JSDoc function.
+            var parent = node.parent;
+            if (ts.isParameter(parent) && ts.isJSDocFunctionType(parent.parent)) {
+                if (ts.last(parent.parent.parameters) !== parent) {
+                    error(node, ts.Diagnostics.A_rest_parameter_must_be_last_in_a_parameter_list);
+                }
+                return;
+            }
+            if (!ts.isJSDocTypeExpression(parent)) {
+                error(node, ts.Diagnostics.JSDoc_may_only_appear_in_the_last_parameter_of_a_signature);
+            }
+            var paramTag = node.parent.parent;
+            if (!ts.isJSDocParameterTag(paramTag)) {
+                error(node, ts.Diagnostics.JSDoc_may_only_appear_in_the_last_parameter_of_a_signature);
+                return;
+            }
+            var param = ts.getParameterSymbolFromJSDoc(paramTag);
+            if (!param) {
+                // We will error in `checkJSDocParameterTag`.
+                return;
+            }
+            var host = ts.getHostSignatureFromJSDoc(paramTag);
+            if (!host || ts.last(host.parameters).symbol !== param) {
+                error(node, ts.Diagnostics.A_rest_parameter_must_be_last_in_a_parameter_list);
+            }
+        }
+        function getTypeFromJSDocVariadicType(node) {
+            var type = getTypeFromTypeNode(node.type);
+            var parent = node.parent;
+            var paramTag = node.parent.parent;
+            if (ts.isJSDocTypeExpression(node.parent) && ts.isJSDocParameterTag(paramTag)) {
+                // Else we will add a diagnostic, see `checkJSDocVariadicType`.
+                var host_1 = ts.getHostSignatureFromJSDoc(paramTag);
+                if (host_1) {
+                    /*
+                    Only return an array type if the corresponding parameter is marked as a rest parameter, or if there are no parameters.
+                    So in the following situation we will not create an array type:
+                        /** @param {...number} a * /
+                        function f(a) {}
+                    Because `a` will just be of type `number | undefined`. A synthetic `...args` will also be added, which *will* get an array type.
+                    */
+                    var lastParamDeclaration = ts.lastOrUndefined(host_1.parameters);
+                    var symbol = ts.getParameterSymbolFromJSDoc(paramTag);
+                    if (!lastParamDeclaration ||
+                        symbol && lastParamDeclaration.symbol === symbol && ts.isRestParameter(lastParamDeclaration)) {
+                        return createArrayType(type);
+                    }
+                }
+            }
+            if (ts.isParameter(parent) && ts.isJSDocFunctionType(parent.parent)) {
+                return createArrayType(type);
+            }
+            return addOptionality(type);
+        }
+        // Function and class expression bodies are checked after all statements in the enclosing body. This is
+        // to ensure constructs like the following are permitted:
+        //     const foo = function () {
+        //        const s = foo();
+        //        return "hello";
+        //     }
+        // Here, performing a full type check of the body of the function expression whilst in the process of
+        // determining the type of foo would cause foo to be given type any because of the recursive reference.
+        // Delaying the type check of the body ensures foo has been assigned a type.
+        function checkNodeDeferred(node) {
+            if (deferredNodes) {
+                deferredNodes.push(node);
+            }
+        }
+        function checkDeferredNodes() {
+            for (var _i = 0, _a = deferredNodes; _i < _a.length; _i++) {
+                var node = _a[_i];
+                switch (node.kind) {
+                    case 192 /* FunctionExpression */:
+                    case 193 /* ArrowFunction */:
+                    case 154 /* MethodDeclaration */:
+                    case 153 /* MethodSignature */:
+                        checkFunctionExpressionOrObjectLiteralMethodDeferred(node);
+                        break;
+                    case 156 /* GetAccessor */:
+                    case 157 /* SetAccessor */:
+                        checkAccessorDeclaration(node);
+                        break;
+                    case 205 /* ClassExpression */:
+                        checkClassExpressionDeferred(node);
+                        break;
+                }
+            }
+        }
+        function checkSourceFile(node) {
+            ts.performance.mark("beforeCheck");
+            checkSourceFileWorker(node);
+            ts.performance.mark("afterCheck");
+            ts.performance.measure("Check", "beforeCheck", "afterCheck");
+        }
+        function unusedIsError(kind) {
+            switch (kind) {
+                case 0 /* Local */:
+                    return !!compilerOptions.noUnusedLocals;
+                case 1 /* Parameter */:
+                    return !!compilerOptions.noUnusedParameters;
+                default:
+                    return ts.Debug.assertNever(kind);
+            }
+        }
+        function getPotentiallyUnusedIdentifiers(sourceFile) {
+            return allPotentiallyUnusedIdentifiers.get(sourceFile.path) || ts.emptyArray;
+        }
+        // Fully type check a source file and collect the relevant diagnostics.
+        function checkSourceFileWorker(node) {
+            var links = getNodeLinks(node);
+            if (!(links.flags & 1 /* TypeChecked */)) {
+                // If skipLibCheck is enabled, skip type checking if file is a declaration file.
+                // If skipDefaultLibCheck is enabled, skip type checking if file contains a
+                // '/// <reference no-default-lib="true"/>' directive.
+                if (compilerOptions.skipLibCheck && node.isDeclarationFile || compilerOptions.skipDefaultLibCheck && node.hasNoDefaultLib) {
+                    return;
+                }
+                // Grammar checking
+                checkGrammarSourceFile(node);
+                ts.clear(potentialThisCollisions);
+                ts.clear(potentialNewTargetCollisions);
+                deferredNodes = [];
+                ts.forEach(node.statements, checkSourceElement);
+                checkDeferredNodes();
+                if (ts.isExternalOrCommonJsModule(node)) {
+                    registerForUnusedIdentifiersCheck(node);
+                }
+                if (!node.isDeclarationFile && (compilerOptions.noUnusedLocals || compilerOptions.noUnusedParameters)) {
+                    checkUnusedIdentifiers(getPotentiallyUnusedIdentifiers(node), function (kind, diag) {
+                        if (unusedIsError(kind)) {
+                            diagnostics.add(diag);
+                        }
+                    });
+                }
+                deferredNodes = undefined;
+                if (ts.isExternalOrCommonJsModule(node)) {
+                    checkExternalModuleExports(node);
+                }
+                if (potentialThisCollisions.length) {
+                    ts.forEach(potentialThisCollisions, checkIfThisIsCapturedInEnclosingScope);
+                    ts.clear(potentialThisCollisions);
+                }
+                if (potentialNewTargetCollisions.length) {
+                    ts.forEach(potentialNewTargetCollisions, checkIfNewTargetIsCapturedInEnclosingScope);
+                    ts.clear(potentialNewTargetCollisions);
+                }
+                links.flags |= 1 /* TypeChecked */;
+            }
+        }
+        function getDiagnostics(sourceFile, ct) {
+            try {
+                // Record the cancellation token so it can be checked later on during checkSourceElement.
+                // Do this in a finally block so we can ensure that it gets reset back to nothing after
+                // this call is done.
+                cancellationToken = ct;
+                return getDiagnosticsWorker(sourceFile);
+            }
+            finally {
+                cancellationToken = undefined;
+            }
+        }
+        function getDiagnosticsWorker(sourceFile) {
+            throwIfNonDiagnosticsProducing();
+            if (sourceFile) {
+                // Some global diagnostics are deferred until they are needed and
+                // may not be reported in the firt call to getGlobalDiagnostics.
+                // We should catch these changes and report them.
+                var previousGlobalDiagnostics = diagnostics.getGlobalDiagnostics();
+                var previousGlobalDiagnosticsSize = previousGlobalDiagnostics.length;
+                checkSourceFile(sourceFile);
+                var semanticDiagnostics = diagnostics.getDiagnostics(sourceFile.fileName);
+                var currentGlobalDiagnostics = diagnostics.getGlobalDiagnostics();
+                if (currentGlobalDiagnostics !== previousGlobalDiagnostics) {
+                    // If the arrays are not the same reference, new diagnostics were added.
+                    var deferredGlobalDiagnostics = ts.relativeComplement(previousGlobalDiagnostics, currentGlobalDiagnostics, ts.compareDiagnostics);
+                    return ts.concatenate(deferredGlobalDiagnostics, semanticDiagnostics);
+                }
+                else if (previousGlobalDiagnosticsSize === 0 && currentGlobalDiagnostics.length > 0) {
+                    // If the arrays are the same reference, but the length has changed, a single
+                    // new diagnostic was added as DiagnosticCollection attempts to reuse the
+                    // same array.
+                    return ts.concatenate(currentGlobalDiagnostics, semanticDiagnostics);
+                }
+                return semanticDiagnostics;
+            }
+            // Global diagnostics are always added when a file is not provided to
+            // getDiagnostics
+            ts.forEach(host.getSourceFiles(), checkSourceFile);
+            return diagnostics.getDiagnostics();
+        }
+        function getGlobalDiagnostics() {
+            throwIfNonDiagnosticsProducing();
+            return diagnostics.getGlobalDiagnostics();
+        }
+        function throwIfNonDiagnosticsProducing() {
+            if (!produceDiagnostics) {
+                throw new Error("Trying to get diagnostics from a type checker that does not produce them.");
+            }
+        }
+        // Language service support
+        function getSymbolsInScope(location, meaning) {
+            if (location.flags & 8388608 /* InWithStatement */) {
+                // We cannot answer semantic questions within a with block, do not proceed any further
+                return [];
+            }
+            var symbols = ts.createSymbolTable();
+            var isStatic = false;
+            populateSymbols();
+            return symbolsToArray(symbols);
+            function populateSymbols() {
+                while (location) {
+                    if (location.locals && !isGlobalSourceFile(location)) {
+                        copySymbols(location.locals, meaning);
+                    }
+                    switch (location.kind) {
+                        case 239 /* ModuleDeclaration */:
+                            copySymbols(getSymbolOfNode(location).exports, meaning & 2623475 /* ModuleMember */);
+                            break;
+                        case 238 /* EnumDeclaration */:
+                            copySymbols(getSymbolOfNode(location).exports, meaning & 8 /* EnumMember */);
+                            break;
+                        case 205 /* ClassExpression */:
+                            var className = location.name;
+                            if (className) {
+                                copySymbol(location.symbol, meaning);
+                            }
+                        // falls through
+                        // this fall-through is necessary because we would like to handle
+                        // type parameter inside class expression similar to how we handle it in classDeclaration and interface Declaration
+                        case 235 /* ClassDeclaration */:
+                        case 236 /* InterfaceDeclaration */:
+                            // If we didn't come from static member of class or interface,
+                            // add the type parameters into the symbol table
+                            // (type parameters of classDeclaration/classExpression and interface are in member property of the symbol.
+                            // Note: that the memberFlags come from previous iteration.
+                            if (!isStatic) {
+                                copySymbols(getMembersOfSymbol(getSymbolOfNode(location)), meaning & 67901928 /* Type */);
+                            }
+                            break;
+                        case 192 /* FunctionExpression */:
+                            var funcName = location.name;
+                            if (funcName) {
+                                copySymbol(location.symbol, meaning);
+                            }
+                            break;
+                    }
+                    if (ts.introducesArgumentsExoticObject(location)) {
+                        copySymbol(argumentsSymbol, meaning);
+                    }
+                    isStatic = ts.hasModifier(location, 32 /* Static */);
+                    location = location.parent;
+                }
+                copySymbols(globals, meaning);
+            }
+            /**
+             * Copy the given symbol into symbol tables if the symbol has the given meaning
+             * and it doesn't already existed in the symbol table
+             * @param key a key for storing in symbol table; if undefined, use symbol.name
+             * @param symbol the symbol to be added into symbol table
+             * @param meaning meaning of symbol to filter by before adding to symbol table
+             */
+            function copySymbol(symbol, meaning) {
+                if (ts.getCombinedLocalAndExportSymbolFlags(symbol) & meaning) {
+                    var id = symbol.escapedName;
+                    // We will copy all symbol regardless of its reserved name because
+                    // symbolsToArray will check whether the key is a reserved name and
+                    // it will not copy symbol with reserved name to the array
+                    if (!symbols.has(id)) {
+                        symbols.set(id, symbol);
+                    }
+                }
+            }
+            function copySymbols(source, meaning) {
+                if (meaning) {
+                    source.forEach(function (symbol) {
+                        copySymbol(symbol, meaning);
+                    });
+                }
+            }
+        }
+        function isTypeDeclarationName(name) {
+            return name.kind === 71 /* Identifier */ &&
+                isTypeDeclaration(name.parent) &&
+                name.parent.name === name;
+        }
+        function isTypeDeclaration(node) {
+            switch (node.kind) {
+                case 148 /* TypeParameter */:
+                case 235 /* ClassDeclaration */:
+                case 236 /* InterfaceDeclaration */:
+                case 237 /* TypeAliasDeclaration */:
+                case 238 /* EnumDeclaration */:
+                    return true;
+                default:
+                    return false;
+            }
+        }
+        // True if the given identifier is part of a type reference
+        function isTypeReferenceIdentifier(node) {
+            while (node.parent.kind === 146 /* QualifiedName */) {
+                node = node.parent;
+            }
+            return node.parent.kind === 162 /* TypeReference */;
+        }
+        function isHeritageClauseElementIdentifier(node) {
+            while (node.parent.kind === 185 /* PropertyAccessExpression */) {
+                node = node.parent;
+            }
+            return node.parent.kind === 207 /* ExpressionWithTypeArguments */;
+        }
+        function forEachEnclosingClass(node, callback) {
+            var result;
+            while (true) {
+                node = ts.getContainingClass(node);
+                if (!node)
+                    break;
+                if (result = callback(node))
+                    break;
+            }
+            return result;
+        }
+        function isNodeWithinConstructorOfClass(node, classDeclaration) {
+            return ts.findAncestor(node, function (element) {
+                if (ts.isConstructorDeclaration(element) && ts.nodeIsPresent(element.body) && element.parent === classDeclaration) {
+                    return true;
+                }
+                else if (element === classDeclaration || ts.isFunctionLikeDeclaration(element)) {
+                    return "quit";
+                }
+                return false;
+            });
+        }
+        function isNodeWithinClass(node, classDeclaration) {
+            return !!forEachEnclosingClass(node, function (n) { return n === classDeclaration; });
+        }
+        function getLeftSideOfImportEqualsOrExportAssignment(nodeOnRightSide) {
+            while (nodeOnRightSide.parent.kind === 146 /* QualifiedName */) {
+                nodeOnRightSide = nodeOnRightSide.parent;
+            }
+            if (nodeOnRightSide.parent.kind === 243 /* ImportEqualsDeclaration */) {
+                return nodeOnRightSide.parent.moduleReference === nodeOnRightSide ? nodeOnRightSide.parent : undefined;
+            }
+            if (nodeOnRightSide.parent.kind === 249 /* ExportAssignment */) {
+                return nodeOnRightSide.parent.expression === nodeOnRightSide ? nodeOnRightSide.parent : undefined;
+            }
+            return undefined;
+        }
+        function isInRightSideOfImportOrExportAssignment(node) {
+            return getLeftSideOfImportEqualsOrExportAssignment(node) !== undefined;
+        }
+        function getSpecialPropertyAssignmentSymbolFromEntityName(entityName) {
+            var specialPropertyAssignmentKind = ts.getSpecialPropertyAssignmentKind(entityName.parent.parent);
+            switch (specialPropertyAssignmentKind) {
+                case 1 /* ExportsProperty */:
+                case 3 /* PrototypeProperty */:
+                    return getSymbolOfNode(entityName.parent);
+                case 4 /* ThisProperty */:
+                case 2 /* ModuleExports */:
+                case 5 /* Property */:
+                    return getSymbolOfNode(entityName.parent.parent);
+            }
+        }
+        function isImportTypeQualifierPart(node) {
+            var parent = node.parent;
+            while (ts.isQualifiedName(parent)) {
+                node = parent;
+                parent = parent.parent;
+            }
+            if (parent && parent.kind === 179 /* ImportType */ && parent.qualifier === node) {
+                return parent;
+            }
+            return undefined;
+        }
+        function getSymbolOfEntityNameOrPropertyAccessExpression(entityName) {
+            if (ts.isDeclarationName(entityName)) {
+                return getSymbolOfNode(entityName.parent);
+            }
+            if (ts.isInJavaScriptFile(entityName) &&
+                entityName.parent.kind === 185 /* PropertyAccessExpression */ &&
+                entityName.parent === entityName.parent.parent.left) {
+                // Check if this is a special property assignment
+                var specialPropertyAssignmentSymbol = getSpecialPropertyAssignmentSymbolFromEntityName(entityName);
+                if (specialPropertyAssignmentSymbol) {
+                    return specialPropertyAssignmentSymbol;
+                }
+            }
+            if (entityName.parent.kind === 249 /* ExportAssignment */ && ts.isEntityNameExpression(entityName)) {
+                // Even an entity name expression that doesn't resolve as an entityname may still typecheck as a property access expression
+                var success = resolveEntityName(entityName, 
+                /*all meanings*/ 67216319 /* Value */ | 67901928 /* Type */ | 1920 /* Namespace */ | 2097152 /* Alias */, /*ignoreErrors*/ true);
+                if (success && success !== unknownSymbol) {
+                    return success;
+                }
+            }
+            else if (!ts.isPropertyAccessExpression(entityName) && isInRightSideOfImportOrExportAssignment(entityName)) {
+                // Since we already checked for ExportAssignment, this really could only be an Import
+                var importEqualsDeclaration = ts.getAncestor(entityName, 243 /* ImportEqualsDeclaration */);
+                ts.Debug.assert(importEqualsDeclaration !== undefined);
+                return getSymbolOfPartOfRightHandSideOfImportEquals(entityName, /*dontResolveAlias*/ true);
+            }
+            if (!ts.isPropertyAccessExpression(entityName)) {
+                var possibleImportNode = isImportTypeQualifierPart(entityName);
+                if (possibleImportNode) {
+                    getTypeFromTypeNode(possibleImportNode);
+                    var sym = getNodeLinks(entityName).resolvedSymbol;
+                    return sym === unknownSymbol ? undefined : sym;
+                }
+            }
+            while (ts.isRightSideOfQualifiedNameOrPropertyAccess(entityName)) {
+                entityName = entityName.parent;
+            }
+            if (isHeritageClauseElementIdentifier(entityName)) {
+                var meaning = 0 /* None */;
+                // In an interface or class, we're definitely interested in a type.
+                if (entityName.parent.kind === 207 /* ExpressionWithTypeArguments */) {
+                    meaning = 67901928 /* Type */;
+                    // In a class 'extends' clause we are also looking for a value.
+                    if (ts.isExpressionWithTypeArgumentsInClassExtendsClause(entityName.parent)) {
+                        meaning |= 67216319 /* Value */;
+                    }
+                }
+                else {
+                    meaning = 1920 /* Namespace */;
+                }
+                meaning |= 2097152 /* Alias */;
+                var entityNameSymbol = ts.isEntityNameExpression(entityName) ? resolveEntityName(entityName, meaning) : undefined;
+                if (entityNameSymbol) {
+                    return entityNameSymbol;
+                }
+            }
+            if (entityName.parent.kind === 293 /* JSDocParameterTag */) {
+                return ts.getParameterSymbolFromJSDoc(entityName.parent);
+            }
+            if (entityName.parent.kind === 148 /* TypeParameter */ && entityName.parent.parent.kind === 296 /* JSDocTemplateTag */) {
+                ts.Debug.assert(!ts.isInJavaScriptFile(entityName)); // Otherwise `isDeclarationName` would have been true.
+                var typeParameter = ts.getTypeParameterFromJsDoc(entityName.parent);
+                return typeParameter && typeParameter.symbol;
+            }
+            if (ts.isExpressionNode(entityName)) {
+                if (ts.nodeIsMissing(entityName)) {
+                    // Missing entity name.
+                    return undefined;
+                }
+                if (entityName.kind === 71 /* Identifier */) {
+                    if (ts.isJSXTagName(entityName) && isJsxIntrinsicIdentifier(entityName)) {
+                        var symbol = getIntrinsicTagSymbol(entityName.parent);
+                        return symbol === unknownSymbol ? undefined : symbol;
+                    }
+                    return resolveEntityName(entityName, 67216319 /* Value */, /*ignoreErrors*/ false, /*dontResolveAlias*/ true);
+                }
+                else if (entityName.kind === 185 /* PropertyAccessExpression */ || entityName.kind === 146 /* QualifiedName */) {
+                    var links = getNodeLinks(entityName);
+                    if (links.resolvedSymbol) {
+                        return links.resolvedSymbol;
+                    }
+                    if (entityName.kind === 185 /* PropertyAccessExpression */) {
+                        checkPropertyAccessExpression(entityName);
+                    }
+                    else {
+                        checkQualifiedName(entityName);
+                    }
+                    return links.resolvedSymbol;
+                }
+            }
+            else if (isTypeReferenceIdentifier(entityName)) {
+                var meaning = entityName.parent.kind === 162 /* TypeReference */ ? 67901928 /* Type */ : 1920 /* Namespace */;
+                return resolveEntityName(entityName, meaning, /*ignoreErrors*/ false, /*dontResolveAlias*/ true);
+            }
+            else if (entityName.parent.kind === 262 /* JsxAttribute */) {
+                return getJsxAttributePropertySymbol(entityName.parent);
+            }
+            if (entityName.parent.kind === 161 /* TypePredicate */) {
+                return resolveEntityName(entityName, /*meaning*/ 1 /* FunctionScopedVariable */);
+            }
+            // Do we want to return undefined here?
+            return undefined;
+        }
+        function getSymbolAtLocation(node) {
+            if (node.kind === 274 /* SourceFile */) {
+                return ts.isExternalModule(node) ? getMergedSymbol(node.symbol) : undefined;
+            }
+            var parent = node.parent;
+            var grandParent = parent.parent;
+            if (node.flags & 8388608 /* InWithStatement */) {
+                // We cannot answer semantic questions within a with block, do not proceed any further
+                return undefined;
+            }
+            if (isDeclarationNameOrImportPropertyName(node)) {
+                // This is a declaration, call getSymbolOfNode
+                return getSymbolOfNode(parent);
+            }
+            else if (ts.isLiteralComputedPropertyDeclarationName(node)) {
+                return getSymbolOfNode(parent.parent);
+            }
+            if (node.kind === 71 /* Identifier */) {
+                if (isInRightSideOfImportOrExportAssignment(node)) {
+                    return getSymbolOfEntityNameOrPropertyAccessExpression(node);
+                }
+                else if (parent.kind === 182 /* BindingElement */ &&
+                    grandParent.kind === 180 /* ObjectBindingPattern */ &&
+                    node === parent.propertyName) {
+                    var typeOfPattern = getTypeOfNode(grandParent);
+                    var propertyDeclaration = typeOfPattern && getPropertyOfType(typeOfPattern, node.escapedText);
+                    if (propertyDeclaration) {
+                        return propertyDeclaration;
+                    }
+                }
+            }
+            switch (node.kind) {
+                case 71 /* Identifier */:
+                case 185 /* PropertyAccessExpression */:
+                case 146 /* QualifiedName */:
+                    return getSymbolOfEntityNameOrPropertyAccessExpression(node);
+                case 99 /* ThisKeyword */:
+                    var container = ts.getThisContainer(node, /*includeArrowFunctions*/ false);
+                    if (ts.isFunctionLike(container)) {
+                        var sig = getSignatureFromDeclaration(container);
+                        if (sig.thisParameter) {
+                            return sig.thisParameter;
+                        }
+                    }
+                    if (ts.isInExpressionContext(node)) {
+                        return checkExpression(node).symbol;
+                    }
+                // falls through
+                case 174 /* ThisType */:
+                    return getTypeFromThisTypeNode(node).symbol;
+                case 97 /* SuperKeyword */:
+                    return checkExpression(node).symbol;
+                case 123 /* ConstructorKeyword */:
+                    // constructor keyword for an overload, should take us to the definition if it exist
+                    var constructorDeclaration = node.parent;
+                    if (constructorDeclaration && constructorDeclaration.kind === 155 /* Constructor */) {
+                        return constructorDeclaration.parent.symbol;
+                    }
+                    return undefined;
+                case 9 /* StringLiteral */:
+                case 13 /* NoSubstitutionTemplateLiteral */:
+                    // 1). import x = require("./mo/*gotToDefinitionHere*/d")
+                    // 2). External module name in an import declaration
+                    // 3). Dynamic import call or require in javascript
+                    // 4). type A = import("./f/*gotToDefinitionHere*/oo")
+                    if ((ts.isExternalModuleImportEqualsDeclaration(node.parent.parent) && ts.getExternalModuleImportEqualsDeclarationExpression(node.parent.parent) === node) ||
+                        ((node.parent.kind === 244 /* ImportDeclaration */ || node.parent.kind === 250 /* ExportDeclaration */) && node.parent.moduleSpecifier === node) ||
+                        ((ts.isInJavaScriptFile(node) && ts.isRequireCall(node.parent, /*checkArgumentIsStringLiteralLike*/ false)) || ts.isImportCall(node.parent)) ||
+                        (ts.isLiteralTypeNode(node.parent) && ts.isLiteralImportTypeNode(node.parent.parent) && node.parent.parent.argument === node.parent)) {
+                        return resolveExternalModuleName(node, node);
+                    }
+                // falls through
+                case 8 /* NumericLiteral */:
+                    // index access
+                    var objectType = ts.isElementAccessExpression(parent)
+                        ? parent.argumentExpression === node ? getTypeOfExpression(parent.expression) : undefined
+                        : ts.isLiteralTypeNode(parent) && ts.isIndexedAccessTypeNode(grandParent)
+                            ? getTypeFromTypeNode(grandParent.objectType)
+                            : undefined;
+                    return objectType && getPropertyOfType(objectType, ts.escapeLeadingUnderscores(node.text));
+                case 79 /* DefaultKeyword */:
+                case 89 /* FunctionKeyword */:
+                case 36 /* EqualsGreaterThanToken */:
+                    return getSymbolOfNode(node.parent);
+                case 179 /* ImportType */:
+                    return ts.isLiteralImportTypeNode(node) ? getSymbolAtLocation(node.argument.literal) : undefined;
+                default:
+                    return undefined;
+            }
+        }
+        function getShorthandAssignmentValueSymbol(location) {
+            if (location && location.kind === 271 /* ShorthandPropertyAssignment */) {
+                return resolveEntityName(location.name, 67216319 /* Value */ | 2097152 /* Alias */);
+            }
+            return undefined;
+        }
+        /** Returns the target of an export specifier without following aliases */
+        function getExportSpecifierLocalTargetSymbol(node) {
+            return node.parent.parent.moduleSpecifier ?
+                getExternalModuleMember(node.parent.parent, node) :
+                resolveEntityName(node.propertyName || node.name, 67216319 /* Value */ | 67901928 /* Type */ | 1920 /* Namespace */ | 2097152 /* Alias */);
+        }
+        function getTypeOfNode(node) {
+            if (node.flags & 8388608 /* InWithStatement */) {
+                // We cannot answer semantic questions within a with block, do not proceed any further
+                return errorType;
+            }
+            if (ts.isPartOfTypeNode(node)) {
+                var typeFromTypeNode = getTypeFromTypeNode(node);
+                if (typeFromTypeNode && ts.isExpressionWithTypeArgumentsInClassImplementsClause(node)) {
+                    var containingClass = ts.getContainingClass(node);
+                    var classType = getTypeOfNode(containingClass);
+                    typeFromTypeNode = getTypeWithThisArgument(typeFromTypeNode, classType.thisType);
+                }
+                return typeFromTypeNode;
+            }
+            if (ts.isExpressionNode(node)) {
+                return getRegularTypeOfExpression(node);
+            }
+            if (ts.isExpressionWithTypeArgumentsInClassExtendsClause(node)) {
+                // A SyntaxKind.ExpressionWithTypeArguments is considered a type node, except when it occurs in the
+                // extends clause of a class. We handle that case here.
+                var classNode = ts.getContainingClass(node);
+                var classType = getDeclaredTypeOfSymbol(getSymbolOfNode(classNode));
+                var baseType = getBaseTypes(classType)[0];
+                return baseType && getTypeWithThisArgument(baseType, classType.thisType);
+            }
+            if (isTypeDeclaration(node)) {
+                // In this case, we call getSymbolOfNode instead of getSymbolAtLocation because it is a declaration
+                var symbol = getSymbolOfNode(node);
+                return getDeclaredTypeOfSymbol(symbol);
+            }
+            if (isTypeDeclarationName(node)) {
+                var symbol = getSymbolAtLocation(node);
+                return symbol && getDeclaredTypeOfSymbol(symbol);
+            }
+            if (ts.isDeclaration(node)) {
+                // In this case, we call getSymbolOfNode instead of getSymbolAtLocation because it is a declaration
+                var symbol = getSymbolOfNode(node);
+                return getTypeOfSymbol(symbol);
+            }
+            if (isDeclarationNameOrImportPropertyName(node)) {
+                var symbol = getSymbolAtLocation(node);
+                return symbol && getTypeOfSymbol(symbol);
+            }
+            if (ts.isBindingPattern(node)) {
+                return getTypeForVariableLikeDeclaration(node.parent, /*includeOptionality*/ true);
+            }
+            if (isInRightSideOfImportOrExportAssignment(node)) {
+                var symbol = getSymbolAtLocation(node);
+                if (symbol) {
+                    var declaredType = getDeclaredTypeOfSymbol(symbol);
+                    return declaredType !== errorType ? declaredType : getTypeOfSymbol(symbol);
+                }
+            }
+            return errorType;
+        }
+        // Gets the type of object literal or array literal of destructuring assignment.
+        // { a } from
+        //     for ( { a } of elems) {
+        //     }
+        // [ a ] from
+        //     [a] = [ some array ...]
+        function getTypeOfArrayLiteralOrObjectLiteralDestructuringAssignment(expr) {
+            ts.Debug.assert(expr.kind === 184 /* ObjectLiteralExpression */ || expr.kind === 183 /* ArrayLiteralExpression */);
+            // If this is from "for of"
+            //     for ( { a } of elems) {
+            //     }
+            if (expr.parent.kind === 222 /* ForOfStatement */) {
+                var iteratedType = checkRightHandSideOfForOf(expr.parent.expression, expr.parent.awaitModifier);
+                return checkDestructuringAssignment(expr, iteratedType || errorType);
+            }
+            // If this is from "for" initializer
+            //     for ({a } = elems[0];.....) { }
+            if (expr.parent.kind === 200 /* BinaryExpression */) {
+                var iteratedType = getTypeOfExpression(expr.parent.right);
+                return checkDestructuringAssignment(expr, iteratedType || errorType);
+            }
+            // If this is from nested object binding pattern
+            //     for ({ skills: { primary, secondary } } = multiRobot, i = 0; i < 1; i++) {
+            if (expr.parent.kind === 270 /* PropertyAssignment */) {
+                var typeOfParentObjectLiteral = getTypeOfArrayLiteralOrObjectLiteralDestructuringAssignment(expr.parent.parent);
+                return checkObjectLiteralDestructuringPropertyAssignment(typeOfParentObjectLiteral || errorType, expr.parent); // TODO: GH#18217
+            }
+            // Array literal assignment - array destructuring pattern
+            ts.Debug.assert(expr.parent.kind === 183 /* ArrayLiteralExpression */);
+            //    [{ property1: p1, property2 }] = elems;
+            var typeOfArrayLiteral = getTypeOfArrayLiteralOrObjectLiteralDestructuringAssignment(expr.parent);
+            var elementType = checkIteratedTypeOrElementType(typeOfArrayLiteral || errorType, expr.parent, /*allowStringInput*/ false, /*allowAsyncIterables*/ false) || errorType;
+            return checkArrayLiteralDestructuringElementAssignment(expr.parent, typeOfArrayLiteral, expr.parent.elements.indexOf(expr), elementType || errorType); // TODO: GH#18217
+        }
+        // Gets the property symbol corresponding to the property in destructuring assignment
+        // 'property1' from
+        //     for ( { property1: a } of elems) {
+        //     }
+        // 'property1' at location 'a' from:
+        //     [a] = [ property1, property2 ]
+        function getPropertySymbolOfDestructuringAssignment(location) {
+            // Get the type of the object or array literal and then look for property of given name in the type
+            var typeOfObjectLiteral = getTypeOfArrayLiteralOrObjectLiteralDestructuringAssignment(location.parent.parent);
+            return typeOfObjectLiteral && getPropertyOfType(typeOfObjectLiteral, location.escapedText);
+        }
+        function getRegularTypeOfExpression(expr) {
+            if (ts.isRightSideOfQualifiedNameOrPropertyAccess(expr)) {
+                expr = expr.parent;
+            }
+            return getRegularTypeOfLiteralType(getTypeOfExpression(expr));
+        }
+        /**
+         * Gets either the static or instance type of a class element, based on
+         * whether the element is declared as "static".
+         */
+        function getParentTypeOfClassElement(node) {
+            var classSymbol = getSymbolOfNode(node.parent);
+            return ts.hasModifier(node, 32 /* Static */)
+                ? getTypeOfSymbol(classSymbol)
+                : getDeclaredTypeOfSymbol(classSymbol);
+        }
+        // Return the list of properties of the given type, augmented with properties from Function
+        // if the type has call or construct signatures
+        function getAugmentedPropertiesOfType(type) {
+            type = getApparentType(type);
+            var propsByName = ts.createSymbolTable(getPropertiesOfType(type));
+            if (typeHasCallOrConstructSignatures(type)) {
+                ts.forEach(getPropertiesOfType(globalFunctionType), function (p) {
+                    if (!propsByName.has(p.escapedName)) {
+                        propsByName.set(p.escapedName, p);
+                    }
+                });
+            }
+            return getNamedMembers(propsByName);
+        }
+        function typeHasCallOrConstructSignatures(type) {
+            return ts.typeHasCallOrConstructSignatures(type, checker);
+        }
+        function getRootSymbols(symbol) {
+            var roots = getImmediateRootSymbols(symbol);
+            return roots ? ts.flatMap(roots, getRootSymbols) : [symbol];
+        }
+        function getImmediateRootSymbols(symbol) {
+            if (ts.getCheckFlags(symbol) & 6 /* Synthetic */) {
+                return ts.mapDefined(getSymbolLinks(symbol).containingType.types, function (type) { return getPropertyOfType(type, symbol.escapedName); });
+            }
+            else if (symbol.flags & 33554432 /* Transient */) {
+                var _a = symbol, leftSpread = _a.leftSpread, rightSpread = _a.rightSpread, syntheticOrigin = _a.syntheticOrigin;
+                return leftSpread ? [leftSpread, rightSpread]
+                    : syntheticOrigin ? [syntheticOrigin]
+                        : ts.singleElementArray(tryGetAliasTarget(symbol));
+            }
+            return undefined;
+        }
+        function tryGetAliasTarget(symbol) {
+            var target;
+            var next = symbol;
+            while (next = getSymbolLinks(next).target) {
+                target = next;
+            }
+            return target;
+        }
+        // Emitter support
+        function isArgumentsLocalBinding(nodeIn) {
+            if (!ts.isGeneratedIdentifier(nodeIn)) {
+                var node = ts.getParseTreeNode(nodeIn, ts.isIdentifier);
+                if (node) {
+                    var isPropertyName_1 = node.parent.kind === 185 /* PropertyAccessExpression */ && node.parent.name === node;
+                    return !isPropertyName_1 && getReferencedValueSymbol(node) === argumentsSymbol;
+                }
+            }
+            return false;
+        }
+        function moduleExportsSomeValue(moduleReferenceExpression) {
+            var moduleSymbol = resolveExternalModuleName(moduleReferenceExpression.parent, moduleReferenceExpression);
+            if (!moduleSymbol || ts.isShorthandAmbientModuleSymbol(moduleSymbol)) {
+                // If the module is not found or is shorthand, assume that it may export a value.
+                return true;
+            }
+            var hasExportAssignment = hasExportAssignmentSymbol(moduleSymbol);
+            // if module has export assignment then 'resolveExternalModuleSymbol' will return resolved symbol for export assignment
+            // otherwise it will return moduleSymbol itself
+            moduleSymbol = resolveExternalModuleSymbol(moduleSymbol);
+            var symbolLinks = getSymbolLinks(moduleSymbol);
+            if (symbolLinks.exportsSomeValue === undefined) {
+                // for export assignments - check if resolved symbol for RHS is itself a value
+                // otherwise - check if at least one export is value
+                symbolLinks.exportsSomeValue = hasExportAssignment
+                    ? !!(moduleSymbol.flags & 67216319 /* Value */)
+                    : ts.forEachEntry(getExportsOfModule(moduleSymbol), isValue);
+            }
+            return symbolLinks.exportsSomeValue;
+            function isValue(s) {
+                s = resolveSymbol(s);
+                return s && !!(s.flags & 67216319 /* Value */);
+            }
+        }
+        function isNameOfModuleOrEnumDeclaration(node) {
+            return ts.isModuleOrEnumDeclaration(node.parent) && node === node.parent.name;
+        }
+        // When resolved as an expression identifier, if the given node references an exported entity, return the declaration
+        // node of the exported entity's container. Otherwise, return undefined.
+        function getReferencedExportContainer(nodeIn, prefixLocals) {
+            var node = ts.getParseTreeNode(nodeIn, ts.isIdentifier);
+            if (node) {
+                // When resolving the export container for the name of a module or enum
+                // declaration, we need to start resolution at the declaration's container.
+                // Otherwise, we could incorrectly resolve the export container as the
+                // declaration if it contains an exported member with the same name.
+                var symbol = getReferencedValueSymbol(node, /*startInDeclarationContainer*/ isNameOfModuleOrEnumDeclaration(node));
+                if (symbol) {
+                    if (symbol.flags & 1048576 /* ExportValue */) {
+                        // If we reference an exported entity within the same module declaration, then whether
+                        // we prefix depends on the kind of entity. SymbolFlags.ExportHasLocal encompasses all the
+                        // kinds that we do NOT prefix.
+                        var exportSymbol = getMergedSymbol(symbol.exportSymbol);
+                        if (!prefixLocals && exportSymbol.flags & 944 /* ExportHasLocal */ && !(exportSymbol.flags & 3 /* Variable */)) {
+                            return undefined;
+                        }
+                        symbol = exportSymbol;
+                    }
+                    var parentSymbol_1 = getParentOfSymbol(symbol);
+                    if (parentSymbol_1) {
+                        if (parentSymbol_1.flags & 512 /* ValueModule */ && parentSymbol_1.valueDeclaration.kind === 274 /* SourceFile */) {
+                            var symbolFile = parentSymbol_1.valueDeclaration;
+                            var referenceFile = ts.getSourceFileOfNode(node);
+                            // If `node` accesses an export and that export isn't in the same file, then symbol is a namespace export, so return undefined.
+                            var symbolIsUmdExport = symbolFile !== referenceFile;
+                            return symbolIsUmdExport ? undefined : symbolFile;
+                        }
+                        return ts.findAncestor(node.parent, function (n) { return ts.isModuleOrEnumDeclaration(n) && getSymbolOfNode(n) === parentSymbol_1; });
+                    }
+                }
+            }
+        }
+        // When resolved as an expression identifier, if the given node references an import, return the declaration of
+        // that import. Otherwise, return undefined.
+        function getReferencedImportDeclaration(nodeIn) {
+            var node = ts.getParseTreeNode(nodeIn, ts.isIdentifier);
+            if (node) {
+                var symbol = getReferencedValueSymbol(node);
+                // We should only get the declaration of an alias if there isn't a local value
+                // declaration for the symbol
+                if (isNonLocalAlias(symbol, /*excludes*/ 67216319 /* Value */)) {
+                    return getDeclarationOfAliasSymbol(symbol);
+                }
+            }
+            return undefined;
+        }
+        function isSymbolOfDeclarationWithCollidingName(symbol) {
+            if (symbol.flags & 418 /* BlockScoped */) {
+                var links = getSymbolLinks(symbol);
+                if (links.isDeclarationWithCollidingName === undefined) {
+                    var container = ts.getEnclosingBlockScopeContainer(symbol.valueDeclaration);
+                    if (ts.isStatementWithLocals(container)) {
+                        var nodeLinks_1 = getNodeLinks(symbol.valueDeclaration);
+                        if (resolveName(container.parent, symbol.escapedName, 67216319 /* Value */, /*nameNotFoundMessage*/ undefined, /*nameArg*/ undefined, /*isUse*/ false)) {
+                            // redeclaration - always should be renamed
+                            links.isDeclarationWithCollidingName = true;
+                        }
+                        else if (nodeLinks_1.flags & 131072 /* CapturedBlockScopedBinding */) {
+                            // binding is captured in the function
+                            // should be renamed if:
+                            // - binding is not top level - top level bindings never collide with anything
+                            // AND
+                            //   - binding is not declared in loop, should be renamed to avoid name reuse across siblings
+                            //     let a, b
+                            //     { let x = 1; a = () => x; }
+                            //     { let x = 100; b = () => x; }
+                            //     console.log(a()); // should print '1'
+                            //     console.log(b()); // should print '100'
+                            //     OR
+                            //   - binding is declared inside loop but not in inside initializer of iteration statement or directly inside loop body
+                            //     * variables from initializer are passed to rewritten loop body as parameters so they are not captured directly
+                            //     * variables that are declared immediately in loop body will become top level variable after loop is rewritten and thus
+                            //       they will not collide with anything
+                            var isDeclaredInLoop = nodeLinks_1.flags & 262144 /* BlockScopedBindingInLoop */;
+                            var inLoopInitializer = ts.isIterationStatement(container, /*lookInLabeledStatements*/ false);
+                            var inLoopBodyBlock = container.kind === 213 /* Block */ && ts.isIterationStatement(container.parent, /*lookInLabeledStatements*/ false);
+                            links.isDeclarationWithCollidingName = !ts.isBlockScopedContainerTopLevel(container) && (!isDeclaredInLoop || (!inLoopInitializer && !inLoopBodyBlock));
+                        }
+                        else {
+                            links.isDeclarationWithCollidingName = false;
+                        }
+                    }
+                }
+                return links.isDeclarationWithCollidingName;
+            }
+            return false;
+        }
+        // When resolved as an expression identifier, if the given node references a nested block scoped entity with
+        // a name that either hides an existing name or might hide it when compiled downlevel,
+        // return the declaration of that entity. Otherwise, return undefined.
+        function getReferencedDeclarationWithCollidingName(nodeIn) {
+            if (!ts.isGeneratedIdentifier(nodeIn)) {
+                var node = ts.getParseTreeNode(nodeIn, ts.isIdentifier);
+                if (node) {
+                    var symbol = getReferencedValueSymbol(node);
+                    if (symbol && isSymbolOfDeclarationWithCollidingName(symbol)) {
+                        return symbol.valueDeclaration;
+                    }
+                }
+            }
+            return undefined;
+        }
+        // Return true if the given node is a declaration of a nested block scoped entity with a name that either hides an
+        // existing name or might hide a name when compiled downlevel
+        function isDeclarationWithCollidingName(nodeIn) {
+            var node = ts.getParseTreeNode(nodeIn, ts.isDeclaration);
+            if (node) {
+                var symbol = getSymbolOfNode(node);
+                if (symbol) {
+                    return isSymbolOfDeclarationWithCollidingName(symbol);
+                }
+            }
+            return false;
+        }
+        function isValueAliasDeclaration(node) {
+            switch (node.kind) {
+                case 243 /* ImportEqualsDeclaration */:
+                case 245 /* ImportClause */:
+                case 246 /* NamespaceImport */:
+                case 248 /* ImportSpecifier */:
+                case 252 /* ExportSpecifier */:
+                    return isAliasResolvedToValue(getSymbolOfNode(node) || unknownSymbol);
+                case 250 /* ExportDeclaration */:
+                    var exportClause = node.exportClause;
+                    return !!exportClause && ts.some(exportClause.elements, isValueAliasDeclaration);
+                case 249 /* ExportAssignment */:
+                    return node.expression
+                        && node.expression.kind === 71 /* Identifier */
+                        ? isAliasResolvedToValue(getSymbolOfNode(node) || unknownSymbol)
+                        : true;
+            }
+            return false;
+        }
+        function isTopLevelValueImportEqualsWithEntityName(nodeIn) {
+            var node = ts.getParseTreeNode(nodeIn, ts.isImportEqualsDeclaration);
+            if (node === undefined || node.parent.kind !== 274 /* SourceFile */ || !ts.isInternalModuleImportEqualsDeclaration(node)) {
+                // parent is not source file or it is not reference to internal module
+                return false;
+            }
+            var isValue = isAliasResolvedToValue(getSymbolOfNode(node));
+            return isValue && node.moduleReference && !ts.nodeIsMissing(node.moduleReference);
+        }
+        function isAliasResolvedToValue(symbol) {
+            var target = resolveAlias(symbol);
+            if (target === unknownSymbol) {
+                return true;
+            }
+            // const enums and modules that contain only const enums are not considered values from the emit perspective
+            // unless 'preserveConstEnums' option is set to true
+            return !!(target.flags & 67216319 /* Value */) &&
+                (compilerOptions.preserveConstEnums || !isConstEnumOrConstEnumOnlyModule(target));
+        }
+        function isConstEnumOrConstEnumOnlyModule(s) {
+            return isConstEnumSymbol(s) || !!s.constEnumOnlyModule;
+        }
+        function isReferencedAliasDeclaration(node, checkChildren) {
+            if (ts.isAliasSymbolDeclaration(node)) {
+                var symbol = getSymbolOfNode(node);
+                if (symbol && getSymbolLinks(symbol).referenced) {
+                    return true;
+                }
+                var target = getSymbolLinks(symbol).target; // TODO: GH#18217
+                if (target && ts.getModifierFlags(node) & 1 /* Export */ && target.flags & 67216319 /* Value */) {
+                    // An `export import ... =` of a value symbol is always considered referenced
+                    return true;
+                }
+            }
+            if (checkChildren) {
+                return !!ts.forEachChild(node, function (node) { return isReferencedAliasDeclaration(node, checkChildren); });
+            }
+            return false;
+        }
+        function isImplementationOfOverload(node) {
+            if (ts.nodeIsPresent(node.body)) {
+                if (ts.isGetAccessor(node) || ts.isSetAccessor(node))
+                    return false; // Get or set accessors can never be overload implementations, but can have up to 2 signatures
+                var symbol = getSymbolOfNode(node);
+                var signaturesOfSymbol = getSignaturesOfSymbol(symbol);
+                // If this function body corresponds to function with multiple signature, it is implementation of overload
+                // e.g.: function foo(a: string): string;
+                //       function foo(a: number): number;
+                //       function foo(a: any) { // This is implementation of the overloads
+                //           return a;
+                //       }
+                return signaturesOfSymbol.length > 1 ||
+                    // If there is single signature for the symbol, it is overload if that signature isn't coming from the node
+                    // e.g.: function foo(a: string): string;
+                    //       function foo(a: any) { // This is implementation of the overloads
+                    //           return a;
+                    //       }
+                    (signaturesOfSymbol.length === 1 && signaturesOfSymbol[0].declaration !== node);
+            }
+            return false;
+        }
+        function isRequiredInitializedParameter(parameter) {
+            return !!strictNullChecks &&
+                !isOptionalParameter(parameter) &&
+                !ts.isJSDocParameterTag(parameter) &&
+                !!parameter.initializer &&
+                !ts.hasModifier(parameter, 92 /* ParameterPropertyModifier */);
+        }
+        function isOptionalUninitializedParameterProperty(parameter) {
+            return strictNullChecks &&
+                isOptionalParameter(parameter) &&
+                !parameter.initializer &&
+                ts.hasModifier(parameter, 92 /* ParameterPropertyModifier */);
+        }
+        function getNodeCheckFlags(node) {
+            return getNodeLinks(node).flags || 0;
+        }
+        function getEnumMemberValue(node) {
+            computeEnumMemberValues(node.parent);
+            return getNodeLinks(node).enumMemberValue;
+        }
+        function canHaveConstantValue(node) {
+            switch (node.kind) {
+                case 273 /* EnumMember */:
+                case 185 /* PropertyAccessExpression */:
+                case 186 /* ElementAccessExpression */:
+                    return true;
+            }
+            return false;
+        }
+        function getConstantValue(node) {
+            if (node.kind === 273 /* EnumMember */) {
+                return getEnumMemberValue(node);
+            }
+            var symbol = getNodeLinks(node).resolvedSymbol;
+            if (symbol && (symbol.flags & 8 /* EnumMember */)) {
+                // inline property\index accesses only for const enums
+                if (ts.isConstEnumDeclaration(symbol.valueDeclaration.parent)) {
+                    return getEnumMemberValue(symbol.valueDeclaration);
+                }
+            }
+            return undefined;
+        }
+        function isFunctionType(type) {
+            return !!(type.flags & 131072 /* Object */) && getSignaturesOfType(type, 0 /* Call */).length > 0;
+        }
+        function getTypeReferenceSerializationKind(typeNameIn, location) {
+            // ensure both `typeName` and `location` are parse tree nodes.
+            var typeName = ts.getParseTreeNode(typeNameIn, ts.isEntityName);
+            if (!typeName)
+                return ts.TypeReferenceSerializationKind.Unknown;
+            if (location) {
+                location = ts.getParseTreeNode(location);
+                if (!location)
+                    return ts.TypeReferenceSerializationKind.Unknown;
+            }
+            // Resolve the symbol as a value to ensure the type can be reached at runtime during emit.
+            var valueSymbol = resolveEntityName(typeName, 67216319 /* Value */, /*ignoreErrors*/ true, /*dontResolveAlias*/ false, location);
+            // Resolve the symbol as a type so that we can provide a more useful hint for the type serializer.
+            var typeSymbol = resolveEntityName(typeName, 67901928 /* Type */, /*ignoreErrors*/ true, /*dontResolveAlias*/ false, location);
+            if (valueSymbol && valueSymbol === typeSymbol) {
+                var globalPromiseSymbol = getGlobalPromiseConstructorSymbol(/*reportErrors*/ false);
+                if (globalPromiseSymbol && valueSymbol === globalPromiseSymbol) {
+                    return ts.TypeReferenceSerializationKind.Promise;
+                }
+                var constructorType = getTypeOfSymbol(valueSymbol);
+                if (constructorType && isConstructorType(constructorType)) {
+                    return ts.TypeReferenceSerializationKind.TypeWithConstructSignatureAndValue;
+                }
+            }
+            // We might not be able to resolve type symbol so use unknown type in that case (eg error case)
+            if (!typeSymbol) {
+                return ts.TypeReferenceSerializationKind.Unknown;
+            }
+            var type = getDeclaredTypeOfSymbol(typeSymbol);
+            if (type === errorType) {
+                return ts.TypeReferenceSerializationKind.Unknown;
+            }
+            else if (type.flags & 3 /* AnyOrUnknown */) {
+                return ts.TypeReferenceSerializationKind.ObjectType;
+            }
+            else if (isTypeAssignableToKind(type, 4096 /* Void */ | 24576 /* Nullable */ | 32768 /* Never */)) {
+                return ts.TypeReferenceSerializationKind.VoidNullableOrNeverType;
+            }
+            else if (isTypeAssignableToKind(type, 272 /* BooleanLike */)) {
+                return ts.TypeReferenceSerializationKind.BooleanType;
+            }
+            else if (isTypeAssignableToKind(type, 168 /* NumberLike */)) {
+                return ts.TypeReferenceSerializationKind.NumberLikeType;
+            }
+            else if (isTypeAssignableToKind(type, 68 /* StringLike */)) {
+                return ts.TypeReferenceSerializationKind.StringLikeType;
+            }
+            else if (isTupleType(type)) {
+                return ts.TypeReferenceSerializationKind.ArrayLikeType;
+            }
+            else if (isTypeAssignableToKind(type, 3072 /* ESSymbolLike */)) {
+                return ts.TypeReferenceSerializationKind.ESSymbolType;
+            }
+            else if (isFunctionType(type)) {
+                return ts.TypeReferenceSerializationKind.TypeWithCallSignature;
+            }
+            else if (isArrayType(type)) {
+                return ts.TypeReferenceSerializationKind.ArrayLikeType;
+            }
+            else {
+                return ts.TypeReferenceSerializationKind.ObjectType;
+            }
+        }
+        function createTypeOfDeclaration(declarationIn, enclosingDeclaration, flags, tracker, addUndefined) {
+            var declaration = ts.getParseTreeNode(declarationIn, ts.isVariableLikeOrAccessor);
+            if (!declaration) {
+                return ts.createToken(119 /* AnyKeyword */);
+            }
+            // Get type of the symbol if this is the valid symbol otherwise get type at location
+            var symbol = getSymbolOfNode(declaration);
+            var type = symbol && !(symbol.flags & (2048 /* TypeLiteral */ | 131072 /* Signature */))
+                ? getWidenedLiteralType(getTypeOfSymbol(symbol))
+                : errorType;
+            if (type.flags & 2048 /* UniqueESSymbol */ &&
+                type.symbol === symbol) {
+                flags |= 1048576 /* AllowUniqueESSymbolType */;
+            }
+            if (addUndefined) {
+                type = getOptionalType(type);
+            }
+            return nodeBuilder.typeToTypeNode(type, enclosingDeclaration, flags | 1024 /* MultilineObjectLiterals */, tracker);
+        }
+        function createReturnTypeOfSignatureDeclaration(signatureDeclarationIn, enclosingDeclaration, flags, tracker) {
+            var signatureDeclaration = ts.getParseTreeNode(signatureDeclarationIn, ts.isFunctionLike);
+            if (!signatureDeclaration) {
+                return ts.createToken(119 /* AnyKeyword */);
+            }
+            var signature = getSignatureFromDeclaration(signatureDeclaration);
+            return nodeBuilder.typeToTypeNode(getReturnTypeOfSignature(signature), enclosingDeclaration, flags | 1024 /* MultilineObjectLiterals */, tracker);
+        }
+        function createTypeOfExpression(exprIn, enclosingDeclaration, flags, tracker) {
+            var expr = ts.getParseTreeNode(exprIn, ts.isExpression);
+            if (!expr) {
+                return ts.createToken(119 /* AnyKeyword */);
+            }
+            var type = getWidenedType(getRegularTypeOfExpression(expr));
+            return nodeBuilder.typeToTypeNode(type, enclosingDeclaration, flags | 1024 /* MultilineObjectLiterals */, tracker);
+        }
+        function hasGlobalName(name) {
+            return globals.has(ts.escapeLeadingUnderscores(name));
+        }
+        function getReferencedValueSymbol(reference, startInDeclarationContainer) {
+            var resolvedSymbol = getNodeLinks(reference).resolvedSymbol;
+            if (resolvedSymbol) {
+                return resolvedSymbol;
+            }
+            var location = reference;
+            if (startInDeclarationContainer) {
+                // When resolving the name of a declaration as a value, we need to start resolution
+                // at a point outside of the declaration.
+                var parent = reference.parent;
+                if (ts.isDeclaration(parent) && reference === parent.name) {
+                    location = getDeclarationContainer(parent);
+                }
+            }
+            return resolveName(location, reference.escapedText, 67216319 /* Value */ | 1048576 /* ExportValue */ | 2097152 /* Alias */, /*nodeNotFoundMessage*/ undefined, /*nameArg*/ undefined, /*isUse*/ true);
+        }
+        function getReferencedValueDeclaration(referenceIn) {
+            if (!ts.isGeneratedIdentifier(referenceIn)) {
+                var reference = ts.getParseTreeNode(referenceIn, ts.isIdentifier);
+                if (reference) {
+                    var symbol = getReferencedValueSymbol(reference);
+                    if (symbol) {
+                        return getExportSymbolOfValueSymbolIfExported(symbol).valueDeclaration;
+                    }
+                }
+            }
+            return undefined;
+        }
+        function isLiteralConstDeclaration(node) {
+            if (ts.isConst(node)) {
+                var type = getTypeOfSymbol(getSymbolOfNode(node));
+                return !!(type.flags & 192 /* StringOrNumberLiteral */ && type.flags & 33554432 /* FreshLiteral */);
+            }
+            return false;
+        }
+        function literalTypeToNode(type) {
+            return ts.createLiteral(type.value);
+        }
+        function createLiteralConstValue(node) {
+            var type = getTypeOfSymbol(getSymbolOfNode(node));
+            return literalTypeToNode(type);
+        }
+        function createResolver() {
+            // this variable and functions that use it are deliberately moved here from the outer scope
+            // to avoid scope pollution
+            var resolvedTypeReferenceDirectives = host.getResolvedTypeReferenceDirectives();
+            var fileToDirective;
+            if (resolvedTypeReferenceDirectives) {
+                // populate reverse mapping: file path -> type reference directive that was resolved to this file
+                fileToDirective = ts.createMap();
+                resolvedTypeReferenceDirectives.forEach(function (resolvedDirective, key) {
+                    if (!resolvedDirective || !resolvedDirective.resolvedFileName) {
+                        return;
+                    }
+                    var file = host.getSourceFile(resolvedDirective.resolvedFileName);
+                    fileToDirective.set(file.path, key);
+                });
+            }
+            return {
+                getReferencedExportContainer: getReferencedExportContainer,
+                getReferencedImportDeclaration: getReferencedImportDeclaration,
+                getReferencedDeclarationWithCollidingName: getReferencedDeclarationWithCollidingName,
+                isDeclarationWithCollidingName: isDeclarationWithCollidingName,
+                isValueAliasDeclaration: function (node) {
+                    node = ts.getParseTreeNode(node);
+                    // Synthesized nodes are always treated like values.
+                    return node ? isValueAliasDeclaration(node) : true;
+                },
+                hasGlobalName: hasGlobalName,
+                isReferencedAliasDeclaration: function (node, checkChildren) {
+                    node = ts.getParseTreeNode(node);
+                    // Synthesized nodes are always treated as referenced.
+                    return node ? isReferencedAliasDeclaration(node, checkChildren) : true;
+                },
+                getNodeCheckFlags: function (node) {
+                    node = ts.getParseTreeNode(node);
+                    return node ? getNodeCheckFlags(node) : 0;
+                },
+                isTopLevelValueImportEqualsWithEntityName: isTopLevelValueImportEqualsWithEntityName,
+                isDeclarationVisible: isDeclarationVisible,
+                isImplementationOfOverload: isImplementationOfOverload,
+                isRequiredInitializedParameter: isRequiredInitializedParameter,
+                isOptionalUninitializedParameterProperty: isOptionalUninitializedParameterProperty,
+                createTypeOfDeclaration: createTypeOfDeclaration,
+                createReturnTypeOfSignatureDeclaration: createReturnTypeOfSignatureDeclaration,
+                createTypeOfExpression: createTypeOfExpression,
+                createLiteralConstValue: createLiteralConstValue,
+                isSymbolAccessible: isSymbolAccessible,
+                isEntityNameVisible: isEntityNameVisible,
+                getConstantValue: function (nodeIn) {
+                    var node = ts.getParseTreeNode(nodeIn, canHaveConstantValue);
+                    return node ? getConstantValue(node) : undefined;
+                },
+                collectLinkedAliases: collectLinkedAliases,
+                getReferencedValueDeclaration: getReferencedValueDeclaration,
+                getTypeReferenceSerializationKind: getTypeReferenceSerializationKind,
+                isOptionalParameter: isOptionalParameter,
+                moduleExportsSomeValue: moduleExportsSomeValue,
+                isArgumentsLocalBinding: isArgumentsLocalBinding,
+                getExternalModuleFileFromDeclaration: getExternalModuleFileFromDeclaration,
+                getTypeReferenceDirectivesForEntityName: getTypeReferenceDirectivesForEntityName,
+                getTypeReferenceDirectivesForSymbol: getTypeReferenceDirectivesForSymbol,
+                isLiteralConstDeclaration: isLiteralConstDeclaration,
+                isLateBound: function (nodeIn) {
+                    var node = ts.getParseTreeNode(nodeIn, ts.isDeclaration);
+                    var symbol = node && getSymbolOfNode(node);
+                    return !!(symbol && ts.getCheckFlags(symbol) & 1024 /* Late */);
+                },
+                getJsxFactoryEntity: function (location) { return location ? (getJsxNamespace(location), (ts.getSourceFileOfNode(location).localJsxFactory || _jsxFactoryEntity)) : _jsxFactoryEntity; },
+                getAllAccessorDeclarations: function (accessor) {
+                    accessor = ts.getParseTreeNode(accessor, ts.isGetOrSetAccessorDeclaration); // TODO: GH#18217
+                    var otherKind = accessor.kind === 157 /* SetAccessor */ ? 156 /* GetAccessor */ : 157 /* SetAccessor */;
+                    var otherAccessor = ts.getDeclarationOfKind(getSymbolOfNode(accessor), otherKind);
+                    var firstAccessor = otherAccessor && (otherAccessor.pos < accessor.pos) ? otherAccessor : accessor;
+                    var secondAccessor = otherAccessor && (otherAccessor.pos < accessor.pos) ? accessor : otherAccessor;
+                    var setAccessor = accessor.kind === 157 /* SetAccessor */ ? accessor : otherAccessor;
+                    var getAccessor = accessor.kind === 156 /* GetAccessor */ ? accessor : otherAccessor;
+                    return {
+                        firstAccessor: firstAccessor,
+                        secondAccessor: secondAccessor,
+                        setAccessor: setAccessor,
+                        getAccessor: getAccessor
+                    };
+                }
+            };
+            function isInHeritageClause(node) {
+                return node.parent && node.parent.kind === 207 /* ExpressionWithTypeArguments */ && node.parent.parent && node.parent.parent.kind === 268 /* HeritageClause */;
+            }
+            // defined here to avoid outer scope pollution
+            function getTypeReferenceDirectivesForEntityName(node) {
+                // program does not have any files with type reference directives - bail out
+                if (!fileToDirective) {
+                    return undefined;
+                }
+                // property access can only be used as values, or types when within an expression with type arguments inside a heritage clause
+                // qualified names can only be used as types\namespaces
+                // identifiers are treated as values only if they appear in type queries
+                var meaning = 67901928 /* Type */ | 1920 /* Namespace */;
+                if ((node.kind === 71 /* Identifier */ && isInTypeQuery(node)) || (node.kind === 185 /* PropertyAccessExpression */ && !isInHeritageClause(node))) {
+                    meaning = 67216319 /* Value */ | 1048576 /* ExportValue */;
+                }
+                var symbol = resolveEntityName(node, meaning, /*ignoreErrors*/ true);
+                return symbol && symbol !== unknownSymbol ? getTypeReferenceDirectivesForSymbol(symbol, meaning) : undefined;
+            }
+            // defined here to avoid outer scope pollution
+            function getTypeReferenceDirectivesForSymbol(symbol, meaning) {
+                // program does not have any files with type reference directives - bail out
+                if (!fileToDirective) {
+                    return undefined;
+                }
+                if (!isSymbolFromTypeDeclarationFile(symbol)) {
+                    return undefined;
+                }
+                // check what declarations in the symbol can contribute to the target meaning
+                var typeReferenceDirectives;
+                for (var _i = 0, _a = symbol.declarations; _i < _a.length; _i++) {
+                    var decl = _a[_i];
+                    // check meaning of the local symbol to see if declaration needs to be analyzed further
+                    if (decl.symbol && decl.symbol.flags & meaning) {
+                        var file = ts.getSourceFileOfNode(decl);
+                        var typeReferenceDirective = fileToDirective.get(file.path);
+                        if (typeReferenceDirective) {
+                            (typeReferenceDirectives || (typeReferenceDirectives = [])).push(typeReferenceDirective);
+                        }
+                        else {
+                            // found at least one entry that does not originate from type reference directive
+                            return undefined;
+                        }
+                    }
+                }
+                return typeReferenceDirectives;
+            }
+            function isSymbolFromTypeDeclarationFile(symbol) {
+                // bail out if symbol does not have associated declarations (i.e. this is transient symbol created for property in binding pattern)
+                if (!symbol.declarations) {
+                    return false;
+                }
+                // walk the parent chain for symbols to make sure that top level parent symbol is in the global scope
+                // external modules cannot define or contribute to type declaration files
+                var current = symbol;
+                while (true) {
+                    var parent = getParentOfSymbol(current);
+                    if (parent) {
+                        current = parent;
+                    }
+                    else {
+                        break;
+                    }
+                }
+                if (current.valueDeclaration && current.valueDeclaration.kind === 274 /* SourceFile */ && current.flags & 512 /* ValueModule */) {
+                    return false;
+                }
+                // check that at least one declaration of top level symbol originates from type declaration file
+                for (var _i = 0, _a = symbol.declarations; _i < _a.length; _i++) {
+                    var decl = _a[_i];
+                    var file = ts.getSourceFileOfNode(decl);
+                    if (fileToDirective.has(file.path)) {
+                        return true;
+                    }
+                }
+                return false;
+            }
+        }
+        function getExternalModuleFileFromDeclaration(declaration) {
+            var specifier = declaration.kind === 239 /* ModuleDeclaration */ ? ts.tryCast(declaration.name, ts.isStringLiteral) : ts.getExternalModuleName(declaration);
+            var moduleSymbol = resolveExternalModuleNameWorker(specifier, specifier, /*moduleNotFoundError*/ undefined); // TODO: GH#18217
+            if (!moduleSymbol) {
+                return undefined;
+            }
+            return ts.getDeclarationOfKind(moduleSymbol, 274 /* SourceFile */);
+        }
+        function initializeTypeChecker() {
+            // Bind all source files and propagate errors
+            for (var _i = 0, _a = host.getSourceFiles(); _i < _a.length; _i++) {
+                var file = _a[_i];
+                ts.bindSourceFile(file, compilerOptions);
+            }
+            // Initialize global symbol table
+            var augmentations;
+            for (var _b = 0, _c = host.getSourceFiles(); _b < _c.length; _b++) {
+                var file = _c[_b];
+                if (!ts.isExternalOrCommonJsModule(file)) {
+                    mergeSymbolTable(globals, file.locals);
+                }
+                if (file.patternAmbientModules && file.patternAmbientModules.length) {
+                    patternAmbientModules = ts.concatenate(patternAmbientModules, file.patternAmbientModules);
+                }
+                if (file.moduleAugmentations.length) {
+                    (augmentations || (augmentations = [])).push(file.moduleAugmentations);
+                }
+                if (file.symbol && file.symbol.globalExports) {
+                    // Merge in UMD exports with first-in-wins semantics (see #9771)
+                    var source = file.symbol.globalExports;
+                    source.forEach(function (sourceSymbol, id) {
+                        if (!globals.has(id)) {
+                            globals.set(id, sourceSymbol);
+                        }
+                    });
+                }
+            }
+            // We do global augmentations separately from module augmentations (and before creating global types) because they
+            //  1. Affect global types. We won't have the correct global types until global augmentations are merged. Also,
+            //  2. Module augmentation instantiation requires creating the type of a module, which, in turn, can require
+            //       checking for an export or property on the module (if export=) which, in turn, can fall back to the
+            //       apparent type of the module - either globalObjectType or globalFunctionType - which wouldn't exist if we
+            //       did module augmentations prior to finalizing the global types.
+            if (augmentations) {
+                // merge _global_ module augmentations.
+                // this needs to be done after global symbol table is initialized to make sure that all ambient modules are indexed
+                for (var _d = 0, augmentations_1 = augmentations; _d < augmentations_1.length; _d++) {
+                    var list = augmentations_1[_d];
+                    for (var _e = 0, list_1 = list; _e < list_1.length; _e++) {
+                        var augmentation = list_1[_e];
+                        if (!ts.isGlobalScopeAugmentation(augmentation.parent))
+                            continue;
+                        mergeModuleAugmentation(augmentation);
+                    }
+                }
+            }
+            // Setup global builtins
+            addToSymbolTable(globals, builtinGlobals, ts.Diagnostics.Declaration_name_conflicts_with_built_in_global_identifier_0);
+            getSymbolLinks(undefinedSymbol).type = undefinedWideningType;
+            getSymbolLinks(argumentsSymbol).type = getGlobalType("IArguments", /*arity*/ 0, /*reportErrors*/ true);
+            getSymbolLinks(unknownSymbol).type = errorType;
+            // Initialize special types
+            globalArrayType = getGlobalType("Array", /*arity*/ 1, /*reportErrors*/ true);
+            globalObjectType = getGlobalType("Object", /*arity*/ 0, /*reportErrors*/ true);
+            globalFunctionType = getGlobalType("Function", /*arity*/ 0, /*reportErrors*/ true);
+            globalStringType = getGlobalType("String", /*arity*/ 0, /*reportErrors*/ true);
+            globalNumberType = getGlobalType("Number", /*arity*/ 0, /*reportErrors*/ true);
+            globalBooleanType = getGlobalType("Boolean", /*arity*/ 0, /*reportErrors*/ true);
+            globalRegExpType = getGlobalType("RegExp", /*arity*/ 0, /*reportErrors*/ true);
+            anyArrayType = createArrayType(anyType);
+            autoArrayType = createArrayType(autoType);
+            if (autoArrayType === emptyObjectType) {
+                // autoArrayType is used as a marker, so even if global Array type is not defined, it needs to be a unique type
+                autoArrayType = createAnonymousType(undefined, emptySymbols, ts.emptyArray, ts.emptyArray, undefined, undefined);
+            }
+            globalReadonlyArrayType = getGlobalTypeOrUndefined("ReadonlyArray", /*arity*/ 1);
+            anyReadonlyArrayType = globalReadonlyArrayType ? createTypeFromGenericGlobalType(globalReadonlyArrayType, [anyType]) : anyArrayType;
+            globalThisType = getGlobalTypeOrUndefined("ThisType", /*arity*/ 1);
+            if (augmentations) {
+                // merge _nonglobal_ module augmentations.
+                // this needs to be done after global symbol table is initialized to make sure that all ambient modules are indexed
+                for (var _f = 0, augmentations_2 = augmentations; _f < augmentations_2.length; _f++) {
+                    var list = augmentations_2[_f];
+                    for (var _g = 0, list_2 = list; _g < list_2.length; _g++) {
+                        var augmentation = list_2[_g];
+                        if (ts.isGlobalScopeAugmentation(augmentation.parent))
+                            continue;
+                        mergeModuleAugmentation(augmentation);
+                    }
+                }
+            }
+        }
+        function checkExternalEmitHelpers(location, helpers) {
+            if ((requestedExternalEmitHelpers & helpers) !== helpers && compilerOptions.importHelpers) {
+                var sourceFile = ts.getSourceFileOfNode(location);
+                if (ts.isEffectiveExternalModule(sourceFile, compilerOptions) && !(location.flags & 4194304 /* Ambient */)) {
+                    var helpersModule = resolveHelpersModule(sourceFile, location);
+                    if (helpersModule !== unknownSymbol) {
+                        var uncheckedHelpers = helpers & ~requestedExternalEmitHelpers;
+                        for (var helper = 1 /* FirstEmitHelper */; helper <= 65536 /* LastEmitHelper */; helper <<= 1) {
+                            if (uncheckedHelpers & helper) {
+                                var name = getHelperName(helper);
+                                var symbol = getSymbol(helpersModule.exports, ts.escapeLeadingUnderscores(name), 67216319 /* Value */);
+                                if (!symbol) {
+                                    error(location, ts.Diagnostics.This_syntax_requires_an_imported_helper_named_1_but_module_0_has_no_exported_member_1, ts.externalHelpersModuleNameText, name);
+                                }
+                            }
+                        }
+                    }
+                    requestedExternalEmitHelpers |= helpers;
+                }
+            }
+        }
+        function getHelperName(helper) {
+            switch (helper) {
+                case 1 /* Extends */: return "__extends";
+                case 2 /* Assign */: return "__assign";
+                case 4 /* Rest */: return "__rest";
+                case 8 /* Decorate */: return "__decorate";
+                case 16 /* Metadata */: return "__metadata";
+                case 32 /* Param */: return "__param";
+                case 64 /* Awaiter */: return "__awaiter";
+                case 128 /* Generator */: return "__generator";
+                case 256 /* Values */: return "__values";
+                case 512 /* Read */: return "__read";
+                case 1024 /* Spread */: return "__spread";
+                case 2048 /* Await */: return "__await";
+                case 4096 /* AsyncGenerator */: return "__asyncGenerator";
+                case 8192 /* AsyncDelegator */: return "__asyncDelegator";
+                case 16384 /* AsyncValues */: return "__asyncValues";
+                case 32768 /* ExportStar */: return "__exportStar";
+                case 65536 /* MakeTemplateObject */: return "__makeTemplateObject";
+                default: return ts.Debug.fail("Unrecognized helper");
+            }
+        }
+        function resolveHelpersModule(node, errorNode) {
+            if (!externalHelpersModule) {
+                externalHelpersModule = resolveExternalModule(node, ts.externalHelpersModuleNameText, ts.Diagnostics.This_syntax_requires_an_imported_helper_but_module_0_cannot_be_found, errorNode) || unknownSymbol;
+            }
+            return externalHelpersModule;
+        }
+        // GRAMMAR CHECKING
+        function checkGrammarDecoratorsAndModifiers(node) {
+            return checkGrammarDecorators(node) || checkGrammarModifiers(node);
+        }
+        function checkGrammarDecorators(node) {
+            if (!node.decorators) {
+                return false;
+            }
+            if (!ts.nodeCanBeDecorated(node, node.parent, node.parent.parent)) {
+                if (node.kind === 154 /* MethodDeclaration */ && !ts.nodeIsPresent(node.body)) {
+                    return grammarErrorOnFirstToken(node, ts.Diagnostics.A_decorator_can_only_decorate_a_method_implementation_not_an_overload);
+                }
+                else {
+                    return grammarErrorOnFirstToken(node, ts.Diagnostics.Decorators_are_not_valid_here);
+                }
+            }
+            else if (node.kind === 156 /* GetAccessor */ || node.kind === 157 /* SetAccessor */) {
+                var accessors = ts.getAllAccessorDeclarations(node.parent.members, node);
+                if (accessors.firstAccessor.decorators && node === accessors.secondAccessor) {
+                    return grammarErrorOnFirstToken(node, ts.Diagnostics.Decorators_cannot_be_applied_to_multiple_get_Slashset_accessors_of_the_same_name);
+                }
+            }
+            return false;
+        }
+        function checkGrammarModifiers(node) {
+            var quickResult = reportObviousModifierErrors(node);
+            if (quickResult !== undefined) {
+                return quickResult;
+            }
+            var lastStatic, lastDeclare, lastAsync, lastReadonly;
+            var flags = 0 /* None */;
+            for (var _i = 0, _a = node.modifiers; _i < _a.length; _i++) {
+                var modifier = _a[_i];
+                if (modifier.kind !== 132 /* ReadonlyKeyword */) {
+                    if (node.kind === 151 /* PropertySignature */ || node.kind === 153 /* MethodSignature */) {
+                        return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_appear_on_a_type_member, ts.tokenToString(modifier.kind));
+                    }
+                    if (node.kind === 160 /* IndexSignature */) {
+                        return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_appear_on_an_index_signature, ts.tokenToString(modifier.kind));
+                    }
+                }
+                switch (modifier.kind) {
+                    case 76 /* ConstKeyword */:
+                        if (node.kind !== 238 /* EnumDeclaration */ && node.parent.kind === 235 /* ClassDeclaration */) {
+                            return grammarErrorOnNode(node, ts.Diagnostics.A_class_member_cannot_have_the_0_keyword, ts.tokenToString(76 /* ConstKeyword */));
+                        }
+                        break;
+                    case 114 /* PublicKeyword */:
+                    case 113 /* ProtectedKeyword */:
+                    case 112 /* PrivateKeyword */:
+                        var text = visibilityToString(ts.modifierToFlag(modifier.kind));
+                        if (flags & 28 /* AccessibilityModifier */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics.Accessibility_modifier_already_seen);
+                        }
+                        else if (flags & 32 /* Static */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_must_precede_1_modifier, text, "static");
+                        }
+                        else if (flags & 64 /* Readonly */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_must_precede_1_modifier, text, "readonly");
+                        }
+                        else if (flags & 256 /* Async */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_must_precede_1_modifier, text, "async");
+                        }
+                        else if (node.parent.kind === 240 /* ModuleBlock */ || node.parent.kind === 274 /* SourceFile */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_appear_on_a_module_or_namespace_element, text);
+                        }
+                        else if (flags & 128 /* Abstract */) {
+                            if (modifier.kind === 112 /* PrivateKeyword */) {
+                                return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_be_used_with_1_modifier, text, "abstract");
+                            }
+                            else {
+                                return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_must_precede_1_modifier, text, "abstract");
+                            }
+                        }
+                        flags |= ts.modifierToFlag(modifier.kind);
+                        break;
+                    case 115 /* StaticKeyword */:
+                        if (flags & 32 /* Static */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_already_seen, "static");
+                        }
+                        else if (flags & 64 /* Readonly */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_must_precede_1_modifier, "static", "readonly");
+                        }
+                        else if (flags & 256 /* Async */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_must_precede_1_modifier, "static", "async");
+                        }
+                        else if (node.parent.kind === 240 /* ModuleBlock */ || node.parent.kind === 274 /* SourceFile */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_appear_on_a_module_or_namespace_element, "static");
+                        }
+                        else if (node.kind === 149 /* Parameter */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_appear_on_a_parameter, "static");
+                        }
+                        else if (flags & 128 /* Abstract */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_be_used_with_1_modifier, "static", "abstract");
+                        }
+                        flags |= 32 /* Static */;
+                        lastStatic = modifier;
+                        break;
+                    case 132 /* ReadonlyKeyword */:
+                        if (flags & 64 /* Readonly */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_already_seen, "readonly");
+                        }
+                        else if (node.kind !== 152 /* PropertyDeclaration */ && node.kind !== 151 /* PropertySignature */ && node.kind !== 160 /* IndexSignature */ && node.kind !== 149 /* Parameter */) {
+                            // If node.kind === SyntaxKind.Parameter, checkParameter report an error if it's not a parameter property.
+                            return grammarErrorOnNode(modifier, ts.Diagnostics.readonly_modifier_can_only_appear_on_a_property_declaration_or_index_signature);
+                        }
+                        flags |= 64 /* Readonly */;
+                        lastReadonly = modifier;
+                        break;
+                    case 84 /* ExportKeyword */:
+                        if (flags & 1 /* Export */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_already_seen, "export");
+                        }
+                        else if (flags & 2 /* Ambient */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_must_precede_1_modifier, "export", "declare");
+                        }
+                        else if (flags & 128 /* Abstract */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_must_precede_1_modifier, "export", "abstract");
+                        }
+                        else if (flags & 256 /* Async */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_must_precede_1_modifier, "export", "async");
+                        }
+                        else if (node.parent.kind === 235 /* ClassDeclaration */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_appear_on_a_class_element, "export");
+                        }
+                        else if (node.kind === 149 /* Parameter */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_appear_on_a_parameter, "export");
+                        }
+                        flags |= 1 /* Export */;
+                        break;
+                    case 79 /* DefaultKeyword */:
+                        var container = node.parent.kind === 274 /* SourceFile */ ? node.parent : node.parent.parent;
+                        if (container.kind === 239 /* ModuleDeclaration */ && !ts.isAmbientModule(container)) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics.A_default_export_can_only_be_used_in_an_ECMAScript_style_module);
+                        }
+                        flags |= 512 /* Default */;
+                        break;
+                    case 124 /* DeclareKeyword */:
+                        if (flags & 2 /* Ambient */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_already_seen, "declare");
+                        }
+                        else if (flags & 256 /* Async */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_be_used_in_an_ambient_context, "async");
+                        }
+                        else if (node.parent.kind === 235 /* ClassDeclaration */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_appear_on_a_class_element, "declare");
+                        }
+                        else if (node.kind === 149 /* Parameter */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_appear_on_a_parameter, "declare");
+                        }
+                        else if ((node.parent.flags & 4194304 /* Ambient */) && node.parent.kind === 240 /* ModuleBlock */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics.A_declare_modifier_cannot_be_used_in_an_already_ambient_context);
+                        }
+                        flags |= 2 /* Ambient */;
+                        lastDeclare = modifier;
+                        break;
+                    case 117 /* AbstractKeyword */:
+                        if (flags & 128 /* Abstract */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_already_seen, "abstract");
+                        }
+                        if (node.kind !== 235 /* ClassDeclaration */) {
+                            if (node.kind !== 154 /* MethodDeclaration */ &&
+                                node.kind !== 152 /* PropertyDeclaration */ &&
+                                node.kind !== 156 /* GetAccessor */ &&
+                                node.kind !== 157 /* SetAccessor */) {
+                                return grammarErrorOnNode(modifier, ts.Diagnostics.abstract_modifier_can_only_appear_on_a_class_method_or_property_declaration);
+                            }
+                            if (!(node.parent.kind === 235 /* ClassDeclaration */ && ts.hasModifier(node.parent, 128 /* Abstract */))) {
+                                return grammarErrorOnNode(modifier, ts.Diagnostics.Abstract_methods_can_only_appear_within_an_abstract_class);
+                            }
+                            if (flags & 32 /* Static */) {
+                                return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_be_used_with_1_modifier, "static", "abstract");
+                            }
+                            if (flags & 8 /* Private */) {
+                                return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_be_used_with_1_modifier, "private", "abstract");
+                            }
+                        }
+                        flags |= 128 /* Abstract */;
+                        break;
+                    case 120 /* AsyncKeyword */:
+                        if (flags & 256 /* Async */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_already_seen, "async");
+                        }
+                        else if (flags & 2 /* Ambient */ || node.parent.flags & 4194304 /* Ambient */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_be_used_in_an_ambient_context, "async");
+                        }
+                        else if (node.kind === 149 /* Parameter */) {
+                            return grammarErrorOnNode(modifier, ts.Diagnostics._0_modifier_cannot_appear_on_a_parameter, "async");
+                        }
+                        flags |= 256 /* Async */;
+                        lastAsync = modifier;
+                        break;
+                }
+            }
+            if (node.kind === 155 /* Constructor */) {
+                if (flags & 32 /* Static */) {
+                    return grammarErrorOnNode(lastStatic, ts.Diagnostics._0_modifier_cannot_appear_on_a_constructor_declaration, "static");
+                }
+                if (flags & 128 /* Abstract */) {
+                    return grammarErrorOnNode(lastStatic, ts.Diagnostics._0_modifier_cannot_appear_on_a_constructor_declaration, "abstract"); // TODO: GH#18217
+                }
+                else if (flags & 256 /* Async */) {
+                    return grammarErrorOnNode(lastAsync, ts.Diagnostics._0_modifier_cannot_appear_on_a_constructor_declaration, "async");
+                }
+                else if (flags & 64 /* Readonly */) {
+                    return grammarErrorOnNode(lastReadonly, ts.Diagnostics._0_modifier_cannot_appear_on_a_constructor_declaration, "readonly");
+                }
+                return false;
+            }
+            else if ((node.kind === 244 /* ImportDeclaration */ || node.kind === 243 /* ImportEqualsDeclaration */) && flags & 2 /* Ambient */) {
+                return grammarErrorOnNode(lastDeclare, ts.Diagnostics.A_0_modifier_cannot_be_used_with_an_import_declaration, "declare");
+            }
+            else if (node.kind === 149 /* Parameter */ && (flags & 92 /* ParameterPropertyModifier */) && ts.isBindingPattern(node.name)) {
+                return grammarErrorOnNode(node, ts.Diagnostics.A_parameter_property_may_not_be_declared_using_a_binding_pattern);
+            }
+            else if (node.kind === 149 /* Parameter */ && (flags & 92 /* ParameterPropertyModifier */) && node.dotDotDotToken) {
+                return grammarErrorOnNode(node, ts.Diagnostics.A_parameter_property_cannot_be_declared_using_a_rest_parameter);
+            }
+            if (flags & 256 /* Async */) {
+                return checkGrammarAsyncModifier(node, lastAsync);
+            }
+            return false;
+        }
+        /**
+         * true | false: Early return this value from checkGrammarModifiers.
+         * undefined: Need to do full checking on the modifiers.
+         */
+        function reportObviousModifierErrors(node) {
+            return !node.modifiers
+                ? false
+                : shouldReportBadModifier(node)
+                    ? grammarErrorOnFirstToken(node, ts.Diagnostics.Modifiers_cannot_appear_here)
+                    : undefined;
+        }
+        function shouldReportBadModifier(node) {
+            switch (node.kind) {
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                case 155 /* Constructor */:
+                case 152 /* PropertyDeclaration */:
+                case 151 /* PropertySignature */:
+                case 154 /* MethodDeclaration */:
+                case 153 /* MethodSignature */:
+                case 160 /* IndexSignature */:
+                case 239 /* ModuleDeclaration */:
+                case 244 /* ImportDeclaration */:
+                case 243 /* ImportEqualsDeclaration */:
+                case 250 /* ExportDeclaration */:
+                case 249 /* ExportAssignment */:
+                case 192 /* FunctionExpression */:
+                case 193 /* ArrowFunction */:
+                case 149 /* Parameter */:
+                    return false;
+                default:
+                    if (node.parent.kind === 240 /* ModuleBlock */ || node.parent.kind === 274 /* SourceFile */) {
+                        return false;
+                    }
+                    switch (node.kind) {
+                        case 234 /* FunctionDeclaration */:
+                            return nodeHasAnyModifiersExcept(node, 120 /* AsyncKeyword */);
+                        case 235 /* ClassDeclaration */:
+                            return nodeHasAnyModifiersExcept(node, 117 /* AbstractKeyword */);
+                        case 236 /* InterfaceDeclaration */:
+                        case 214 /* VariableStatement */:
+                        case 237 /* TypeAliasDeclaration */:
+                            return true;
+                        case 238 /* EnumDeclaration */:
+                            return nodeHasAnyModifiersExcept(node, 76 /* ConstKeyword */);
+                        default:
+                            ts.Debug.fail();
+                            return false;
+                    }
+            }
+        }
+        function nodeHasAnyModifiersExcept(node, allowedModifier) {
+            return node.modifiers.length > 1 || node.modifiers[0].kind !== allowedModifier;
+        }
+        function checkGrammarAsyncModifier(node, asyncModifier) {
+            switch (node.kind) {
+                case 154 /* MethodDeclaration */:
+                case 234 /* FunctionDeclaration */:
+                case 192 /* FunctionExpression */:
+                case 193 /* ArrowFunction */:
+                    return false;
+            }
+            return grammarErrorOnNode(asyncModifier, ts.Diagnostics._0_modifier_cannot_be_used_here, "async");
+        }
+        function checkGrammarForDisallowedTrailingComma(list, diag) {
+            if (diag === void 0) { diag = ts.Diagnostics.Trailing_comma_not_allowed; }
+            if (list && list.hasTrailingComma) {
+                return grammarErrorAtPos(list[0], list.end - ",".length, ",".length, diag);
+            }
+            return false;
+        }
+        function checkGrammarTypeParameterList(typeParameters, file) {
+            if (typeParameters && typeParameters.length === 0) {
+                var start = typeParameters.pos - "<".length;
+                var end = ts.skipTrivia(file.text, typeParameters.end) + ">".length;
+                return grammarErrorAtPos(file, start, end - start, ts.Diagnostics.Type_parameter_list_cannot_be_empty);
+            }
+            return false;
+        }
+        function checkGrammarParameterList(parameters) {
+            var seenOptionalParameter = false;
+            var parameterCount = parameters.length;
+            for (var i = 0; i < parameterCount; i++) {
+                var parameter = parameters[i];
+                if (parameter.dotDotDotToken) {
+                    if (i !== (parameterCount - 1)) {
+                        return grammarErrorOnNode(parameter.dotDotDotToken, ts.Diagnostics.A_rest_parameter_must_be_last_in_a_parameter_list);
+                    }
+                    if (!(parameter.flags & 4194304 /* Ambient */)) { // Allow `...foo,` in ambient declarations; see GH#23070
+                        checkGrammarForDisallowedTrailingComma(parameters, ts.Diagnostics.A_rest_parameter_or_binding_pattern_may_not_have_a_trailing_comma);
+                    }
+                    if (ts.isBindingPattern(parameter.name)) {
+                        return grammarErrorOnNode(parameter.name, ts.Diagnostics.A_rest_element_cannot_contain_a_binding_pattern);
+                    }
+                    if (parameter.questionToken) {
+                        return grammarErrorOnNode(parameter.questionToken, ts.Diagnostics.A_rest_parameter_cannot_be_optional);
+                    }
+                    if (parameter.initializer) {
+                        return grammarErrorOnNode(parameter.name, ts.Diagnostics.A_rest_parameter_cannot_have_an_initializer);
+                    }
+                }
+                else if (parameter.questionToken) {
+                    seenOptionalParameter = true;
+                    if (parameter.initializer) {
+                        return grammarErrorOnNode(parameter.name, ts.Diagnostics.Parameter_cannot_have_question_mark_and_initializer);
+                    }
+                }
+                else if (seenOptionalParameter && !parameter.initializer) {
+                    return grammarErrorOnNode(parameter.name, ts.Diagnostics.A_required_parameter_cannot_follow_an_optional_parameter);
+                }
+            }
+        }
+        function checkGrammarFunctionLikeDeclaration(node) {
+            // Prevent cascading error by short-circuit
+            var file = ts.getSourceFileOfNode(node);
+            return checkGrammarDecoratorsAndModifiers(node) || checkGrammarTypeParameterList(node.typeParameters, file) ||
+                checkGrammarParameterList(node.parameters) || checkGrammarArrowFunction(node, file);
+        }
+        function checkGrammarClassLikeDeclaration(node) {
+            var file = ts.getSourceFileOfNode(node);
+            return checkGrammarClassDeclarationHeritageClauses(node) || checkGrammarTypeParameterList(node.typeParameters, file);
+        }
+        function checkGrammarArrowFunction(node, file) {
+            if (!ts.isArrowFunction(node)) {
+                return false;
+            }
+            var equalsGreaterThanToken = node.equalsGreaterThanToken;
+            var startLine = ts.getLineAndCharacterOfPosition(file, equalsGreaterThanToken.pos).line;
+            var endLine = ts.getLineAndCharacterOfPosition(file, equalsGreaterThanToken.end).line;
+            return startLine !== endLine && grammarErrorOnNode(equalsGreaterThanToken, ts.Diagnostics.Line_terminator_not_permitted_before_arrow);
+        }
+        function checkGrammarIndexSignatureParameters(node) {
+            var parameter = node.parameters[0];
+            if (node.parameters.length !== 1) {
+                if (parameter) {
+                    return grammarErrorOnNode(parameter.name, ts.Diagnostics.An_index_signature_must_have_exactly_one_parameter);
+                }
+                else {
+                    return grammarErrorOnNode(node, ts.Diagnostics.An_index_signature_must_have_exactly_one_parameter);
+                }
+            }
+            if (parameter.dotDotDotToken) {
+                return grammarErrorOnNode(parameter.dotDotDotToken, ts.Diagnostics.An_index_signature_cannot_have_a_rest_parameter);
+            }
+            if (ts.hasModifiers(parameter)) {
+                return grammarErrorOnNode(parameter.name, ts.Diagnostics.An_index_signature_parameter_cannot_have_an_accessibility_modifier);
+            }
+            if (parameter.questionToken) {
+                return grammarErrorOnNode(parameter.questionToken, ts.Diagnostics.An_index_signature_parameter_cannot_have_a_question_mark);
+            }
+            if (parameter.initializer) {
+                return grammarErrorOnNode(parameter.name, ts.Diagnostics.An_index_signature_parameter_cannot_have_an_initializer);
+            }
+            if (!parameter.type) {
+                return grammarErrorOnNode(parameter.name, ts.Diagnostics.An_index_signature_parameter_must_have_a_type_annotation);
+            }
+            if (parameter.type.kind !== 137 /* StringKeyword */ && parameter.type.kind !== 134 /* NumberKeyword */) {
+                var type = getTypeFromTypeNode(parameter.type);
+                if (type.flags & 4 /* String */ || type.flags & 8 /* Number */) {
+                    return grammarErrorOnNode(parameter.name, ts.Diagnostics.An_index_signature_parameter_type_cannot_be_a_type_alias_Consider_writing_0_Colon_1_Colon_2_instead, ts.getTextOfNode(parameter.name), typeToString(type), typeToString(getTypeFromTypeNode(node.type)));
+                }
+                if (type.flags & 262144 /* Union */ && allTypesAssignableToKind(type, 64 /* StringLiteral */, /*strict*/ true)) {
+                    return grammarErrorOnNode(parameter.name, ts.Diagnostics.An_index_signature_parameter_type_cannot_be_a_union_type_Consider_using_a_mapped_object_type_instead);
+                }
+                return grammarErrorOnNode(parameter.name, ts.Diagnostics.An_index_signature_parameter_type_must_be_string_or_number);
+            }
+            if (!node.type) {
+                return grammarErrorOnNode(node, ts.Diagnostics.An_index_signature_must_have_a_type_annotation);
+            }
+            return false;
+        }
+        function checkGrammarIndexSignature(node) {
+            // Prevent cascading error by short-circuit
+            return checkGrammarDecoratorsAndModifiers(node) || checkGrammarIndexSignatureParameters(node);
+        }
+        function checkGrammarForAtLeastOneTypeArgument(node, typeArguments) {
+            if (typeArguments && typeArguments.length === 0) {
+                var sourceFile = ts.getSourceFileOfNode(node);
+                var start = typeArguments.pos - "<".length;
+                var end = ts.skipTrivia(sourceFile.text, typeArguments.end) + ">".length;
+                return grammarErrorAtPos(sourceFile, start, end - start, ts.Diagnostics.Type_argument_list_cannot_be_empty);
+            }
+            return false;
+        }
+        function checkGrammarTypeArguments(node, typeArguments) {
+            return checkGrammarForDisallowedTrailingComma(typeArguments) ||
+                checkGrammarForAtLeastOneTypeArgument(node, typeArguments);
+        }
+        function checkGrammarForOmittedArgument(args) {
+            if (args) {
+                for (var _i = 0, args_5 = args; _i < args_5.length; _i++) {
+                    var arg = args_5[_i];
+                    if (arg.kind === 206 /* OmittedExpression */) {
+                        return grammarErrorAtPos(arg, arg.pos, 0, ts.Diagnostics.Argument_expression_expected);
+                    }
+                }
+            }
+            return false;
+        }
+        function checkGrammarArguments(args) {
+            return checkGrammarForOmittedArgument(args);
+        }
+        function checkGrammarHeritageClause(node) {
+            var types = node.types;
+            if (checkGrammarForDisallowedTrailingComma(types)) {
+                return true;
+            }
+            if (types && types.length === 0) {
+                var listType = ts.tokenToString(node.token);
+                return grammarErrorAtPos(node, types.pos, 0, ts.Diagnostics._0_list_cannot_be_empty, listType);
+            }
+            return ts.some(types, checkGrammarExpressionWithTypeArguments);
+        }
+        function checkGrammarExpressionWithTypeArguments(node) {
+            return checkGrammarTypeArguments(node, node.typeArguments);
+        }
+        function checkGrammarClassDeclarationHeritageClauses(node) {
+            var seenExtendsClause = false;
+            var seenImplementsClause = false;
+            if (!checkGrammarDecoratorsAndModifiers(node) && node.heritageClauses) {
+                for (var _i = 0, _a = node.heritageClauses; _i < _a.length; _i++) {
+                    var heritageClause = _a[_i];
+                    if (heritageClause.token === 85 /* ExtendsKeyword */) {
+                        if (seenExtendsClause) {
+                            return grammarErrorOnFirstToken(heritageClause, ts.Diagnostics.extends_clause_already_seen);
+                        }
+                        if (seenImplementsClause) {
+                            return grammarErrorOnFirstToken(heritageClause, ts.Diagnostics.extends_clause_must_precede_implements_clause);
+                        }
+                        if (heritageClause.types.length > 1) {
+                            return grammarErrorOnFirstToken(heritageClause.types[1], ts.Diagnostics.Classes_can_only_extend_a_single_class);
+                        }
+                        seenExtendsClause = true;
+                    }
+                    else {
+                        ts.Debug.assert(heritageClause.token === 108 /* ImplementsKeyword */);
+                        if (seenImplementsClause) {
+                            return grammarErrorOnFirstToken(heritageClause, ts.Diagnostics.implements_clause_already_seen);
+                        }
+                        seenImplementsClause = true;
+                    }
+                    // Grammar checking heritageClause inside class declaration
+                    checkGrammarHeritageClause(heritageClause);
+                }
+            }
+        }
+        function checkGrammarInterfaceDeclaration(node) {
+            var seenExtendsClause = false;
+            if (node.heritageClauses) {
+                for (var _i = 0, _a = node.heritageClauses; _i < _a.length; _i++) {
+                    var heritageClause = _a[_i];
+                    if (heritageClause.token === 85 /* ExtendsKeyword */) {
+                        if (seenExtendsClause) {
+                            return grammarErrorOnFirstToken(heritageClause, ts.Diagnostics.extends_clause_already_seen);
+                        }
+                        seenExtendsClause = true;
+                    }
+                    else {
+                        ts.Debug.assert(heritageClause.token === 108 /* ImplementsKeyword */);
+                        return grammarErrorOnFirstToken(heritageClause, ts.Diagnostics.Interface_declaration_cannot_have_implements_clause);
+                    }
+                    // Grammar checking heritageClause inside class declaration
+                    checkGrammarHeritageClause(heritageClause);
+                }
+            }
+            return false;
+        }
+        function checkGrammarComputedPropertyName(node) {
+            // If node is not a computedPropertyName, just skip the grammar checking
+            if (node.kind !== 147 /* ComputedPropertyName */) {
+                return false;
+            }
+            var computedPropertyName = node;
+            if (computedPropertyName.expression.kind === 200 /* BinaryExpression */ && computedPropertyName.expression.operatorToken.kind === 26 /* CommaToken */) {
+                return grammarErrorOnNode(computedPropertyName.expression, ts.Diagnostics.A_comma_expression_is_not_allowed_in_a_computed_property_name);
+            }
+            return false;
+        }
+        function checkGrammarForGenerator(node) {
+            if (node.asteriskToken) {
+                ts.Debug.assert(node.kind === 234 /* FunctionDeclaration */ ||
+                    node.kind === 192 /* FunctionExpression */ ||
+                    node.kind === 154 /* MethodDeclaration */);
+                if (node.flags & 4194304 /* Ambient */) {
+                    return grammarErrorOnNode(node.asteriskToken, ts.Diagnostics.Generators_are_not_allowed_in_an_ambient_context);
+                }
+                if (!node.body) {
+                    return grammarErrorOnNode(node.asteriskToken, ts.Diagnostics.An_overload_signature_cannot_be_declared_as_a_generator);
+                }
+            }
+        }
+        function checkGrammarForInvalidQuestionMark(questionToken, message) {
+            return !!questionToken && grammarErrorOnNode(questionToken, message);
+        }
+        function checkGrammarObjectLiteralExpression(node, inDestructuring) {
+            var Flags;
+            (function (Flags) {
+                Flags[Flags["Property"] = 1] = "Property";
+                Flags[Flags["GetAccessor"] = 2] = "GetAccessor";
+                Flags[Flags["SetAccessor"] = 4] = "SetAccessor";
+                Flags[Flags["GetOrSetAccessor"] = 6] = "GetOrSetAccessor";
+            })(Flags || (Flags = {}));
+            var seen = ts.createUnderscoreEscapedMap();
+            for (var _i = 0, _a = node.properties; _i < _a.length; _i++) {
+                var prop = _a[_i];
+                if (prop.kind === 272 /* SpreadAssignment */) {
+                    continue;
+                }
+                var name = prop.name;
+                if (name.kind === 147 /* ComputedPropertyName */) {
+                    // If the name is not a ComputedPropertyName, the grammar checking will skip it
+                    checkGrammarComputedPropertyName(name);
+                }
+                if (prop.kind === 271 /* ShorthandPropertyAssignment */ && !inDestructuring && prop.objectAssignmentInitializer) {
+                    // having objectAssignmentInitializer is only valid in ObjectAssignmentPattern
+                    // outside of destructuring it is a syntax error
+                    return grammarErrorOnNode(prop.equalsToken, ts.Diagnostics.can_only_be_used_in_an_object_literal_property_inside_a_destructuring_assignment);
+                }
+                // Modifiers are never allowed on properties except for 'async' on a method declaration
+                if (prop.modifiers) {
+                    for (var _b = 0, _c = prop.modifiers; _b < _c.length; _b++) { // TODO: GH#19955
+                        var mod = _c[_b];
+                        if (mod.kind !== 120 /* AsyncKeyword */ || prop.kind !== 154 /* MethodDeclaration */) {
+                            grammarErrorOnNode(mod, ts.Diagnostics._0_modifier_cannot_be_used_here, ts.getTextOfNode(mod));
+                        }
+                    }
+                }
+                // ECMA-262 11.1.5 Object Initializer
+                // If previous is not undefined then throw a SyntaxError exception if any of the following conditions are true
+                // a.This production is contained in strict code and IsDataDescriptor(previous) is true and
+                // IsDataDescriptor(propId.descriptor) is true.
+                //    b.IsDataDescriptor(previous) is true and IsAccessorDescriptor(propId.descriptor) is true.
+                //    c.IsAccessorDescriptor(previous) is true and IsDataDescriptor(propId.descriptor) is true.
+                //    d.IsAccessorDescriptor(previous) is true and IsAccessorDescriptor(propId.descriptor) is true
+                // and either both previous and propId.descriptor have[[Get]] fields or both previous and propId.descriptor have[[Set]] fields
+                var currentKind = void 0;
+                switch (prop.kind) {
+                    case 270 /* PropertyAssignment */:
+                    case 271 /* ShorthandPropertyAssignment */:
+                        // Grammar checking for computedPropertyName and shorthandPropertyAssignment
+                        checkGrammarForInvalidQuestionMark(prop.questionToken, ts.Diagnostics.An_object_member_cannot_be_declared_optional);
+                        if (name.kind === 8 /* NumericLiteral */) {
+                            checkGrammarNumericLiteral(name);
+                        }
+                    // falls through
+                    case 154 /* MethodDeclaration */:
+                        currentKind = 1 /* Property */;
+                        break;
+                    case 156 /* GetAccessor */:
+                        currentKind = 2 /* GetAccessor */;
+                        break;
+                    case 157 /* SetAccessor */:
+                        currentKind = 4 /* SetAccessor */;
+                        break;
+                    default:
+                        throw ts.Debug.assertNever(prop, "Unexpected syntax kind:" + prop.kind);
+                }
+                var effectiveName = ts.getPropertyNameForPropertyNameNode(name);
+                if (effectiveName === undefined) {
+                    continue;
+                }
+                var existingKind = seen.get(effectiveName);
+                if (!existingKind) {
+                    seen.set(effectiveName, currentKind);
+                }
+                else {
+                    if (currentKind === 1 /* Property */ && existingKind === 1 /* Property */) {
+                        grammarErrorOnNode(name, ts.Diagnostics.Duplicate_identifier_0, ts.getTextOfNode(name));
+                    }
+                    else if ((currentKind & 6 /* GetOrSetAccessor */) && (existingKind & 6 /* GetOrSetAccessor */)) {
+                        if (existingKind !== 6 /* GetOrSetAccessor */ && currentKind !== existingKind) {
+                            seen.set(effectiveName, currentKind | existingKind);
+                        }
+                        else {
+                            return grammarErrorOnNode(name, ts.Diagnostics.An_object_literal_cannot_have_multiple_get_Slashset_accessors_with_the_same_name);
+                        }
+                    }
+                    else {
+                        return grammarErrorOnNode(name, ts.Diagnostics.An_object_literal_cannot_have_property_and_accessor_with_the_same_name);
+                    }
+                }
+            }
+        }
+        function checkGrammarJsxElement(node) {
+            checkGrammarTypeArguments(node, node.typeArguments);
+            var seen = ts.createUnderscoreEscapedMap();
+            for (var _i = 0, _a = node.attributes.properties; _i < _a.length; _i++) {
+                var attr = _a[_i];
+                if (attr.kind === 264 /* JsxSpreadAttribute */) {
+                    continue;
+                }
+                var name = attr.name, initializer = attr.initializer;
+                if (!seen.get(name.escapedText)) {
+                    seen.set(name.escapedText, true);
+                }
+                else {
+                    return grammarErrorOnNode(name, ts.Diagnostics.JSX_elements_cannot_have_multiple_attributes_with_the_same_name);
+                }
+                if (initializer && initializer.kind === 265 /* JsxExpression */ && !initializer.expression) {
+                    return grammarErrorOnNode(initializer, ts.Diagnostics.JSX_attributes_must_only_be_assigned_a_non_empty_expression);
+                }
+            }
+        }
+        function checkGrammarForInOrForOfStatement(forInOrOfStatement) {
+            if (checkGrammarStatementInAmbientContext(forInOrOfStatement)) {
+                return true;
+            }
+            if (forInOrOfStatement.kind === 222 /* ForOfStatement */ && forInOrOfStatement.awaitModifier) {
+                if ((forInOrOfStatement.flags & 16384 /* AwaitContext */) === 0 /* None */) {
+                    return grammarErrorOnNode(forInOrOfStatement.awaitModifier, ts.Diagnostics.A_for_await_of_statement_is_only_allowed_within_an_async_function_or_async_generator);
+                }
+            }
+            if (forInOrOfStatement.initializer.kind === 233 /* VariableDeclarationList */) {
+                var variableList = forInOrOfStatement.initializer;
+                if (!checkGrammarVariableDeclarationList(variableList)) {
+                    var declarations = variableList.declarations;
+                    // declarations.length can be zero if there is an error in variable declaration in for-of or for-in
+                    // See http://www.ecma-international.org/ecma-262/6.0/#sec-for-in-and-for-of-statements for details
+                    // For example:
+                    //      var let = 10;
+                    //      for (let of [1,2,3]) {} // this is invalid ES6 syntax
+                    //      for (let in [1,2,3]) {} // this is invalid ES6 syntax
+                    // We will then want to skip on grammar checking on variableList declaration
+                    if (!declarations.length) {
+                        return false;
+                    }
+                    if (declarations.length > 1) {
+                        var diagnostic = forInOrOfStatement.kind === 221 /* ForInStatement */
+                            ? ts.Diagnostics.Only_a_single_variable_declaration_is_allowed_in_a_for_in_statement
+                            : ts.Diagnostics.Only_a_single_variable_declaration_is_allowed_in_a_for_of_statement;
+                        return grammarErrorOnFirstToken(variableList.declarations[1], diagnostic);
+                    }
+                    var firstDeclaration = declarations[0];
+                    if (firstDeclaration.initializer) {
+                        var diagnostic = forInOrOfStatement.kind === 221 /* ForInStatement */
+                            ? ts.Diagnostics.The_variable_declaration_of_a_for_in_statement_cannot_have_an_initializer
+                            : ts.Diagnostics.The_variable_declaration_of_a_for_of_statement_cannot_have_an_initializer;
+                        return grammarErrorOnNode(firstDeclaration.name, diagnostic);
+                    }
+                    if (firstDeclaration.type) {
+                        var diagnostic = forInOrOfStatement.kind === 221 /* ForInStatement */
+                            ? ts.Diagnostics.The_left_hand_side_of_a_for_in_statement_cannot_use_a_type_annotation
+                            : ts.Diagnostics.The_left_hand_side_of_a_for_of_statement_cannot_use_a_type_annotation;
+                        return grammarErrorOnNode(firstDeclaration, diagnostic);
+                    }
+                }
+            }
+            return false;
+        }
+        function checkGrammarAccessor(accessor) {
+            var kind = accessor.kind;
+            if (languageVersion < 1 /* ES5 */) {
+                return grammarErrorOnNode(accessor.name, ts.Diagnostics.Accessors_are_only_available_when_targeting_ECMAScript_5_and_higher);
+            }
+            else if (accessor.flags & 4194304 /* Ambient */) {
+                return grammarErrorOnNode(accessor.name, ts.Diagnostics.An_accessor_cannot_be_declared_in_an_ambient_context);
+            }
+            else if (accessor.body === undefined && !ts.hasModifier(accessor, 128 /* Abstract */)) {
+                return grammarErrorAtPos(accessor, accessor.end - 1, ";".length, ts.Diagnostics._0_expected, "{");
+            }
+            else if (accessor.body && ts.hasModifier(accessor, 128 /* Abstract */)) {
+                return grammarErrorOnNode(accessor, ts.Diagnostics.An_abstract_accessor_cannot_have_an_implementation);
+            }
+            else if (accessor.typeParameters) {
+                return grammarErrorOnNode(accessor.name, ts.Diagnostics.An_accessor_cannot_have_type_parameters);
+            }
+            else if (!doesAccessorHaveCorrectParameterCount(accessor)) {
+                return grammarErrorOnNode(accessor.name, kind === 156 /* GetAccessor */ ?
+                    ts.Diagnostics.A_get_accessor_cannot_have_parameters :
+                    ts.Diagnostics.A_set_accessor_must_have_exactly_one_parameter);
+            }
+            else if (kind === 157 /* SetAccessor */) {
+                if (accessor.type) {
+                    return grammarErrorOnNode(accessor.name, ts.Diagnostics.A_set_accessor_cannot_have_a_return_type_annotation);
+                }
+                else {
+                    var parameter = accessor.parameters[0];
+                    if (parameter.dotDotDotToken) {
+                        return grammarErrorOnNode(parameter.dotDotDotToken, ts.Diagnostics.A_set_accessor_cannot_have_rest_parameter);
+                    }
+                    else if (parameter.questionToken) {
+                        return grammarErrorOnNode(parameter.questionToken, ts.Diagnostics.A_set_accessor_cannot_have_an_optional_parameter);
+                    }
+                    else if (parameter.initializer) {
+                        return grammarErrorOnNode(accessor.name, ts.Diagnostics.A_set_accessor_parameter_cannot_have_an_initializer);
+                    }
+                }
+            }
+            return false;
+        }
+        /** Does the accessor have the right number of parameters?
+         * A get accessor has no parameters or a single `this` parameter.
+         * A set accessor has one parameter or a `this` parameter and one more parameter.
+         */
+        function doesAccessorHaveCorrectParameterCount(accessor) {
+            return getAccessorThisParameter(accessor) || accessor.parameters.length === (accessor.kind === 156 /* GetAccessor */ ? 0 : 1);
+        }
+        function getAccessorThisParameter(accessor) {
+            if (accessor.parameters.length === (accessor.kind === 156 /* GetAccessor */ ? 1 : 2)) {
+                return ts.getThisParameter(accessor);
+            }
+        }
+        function checkGrammarTypeOperatorNode(node) {
+            if (node.operator === 141 /* UniqueKeyword */) {
+                if (node.type.kind !== 138 /* SymbolKeyword */) {
+                    return grammarErrorOnNode(node.type, ts.Diagnostics._0_expected, ts.tokenToString(138 /* SymbolKeyword */));
+                }
+                var parent = ts.walkUpParenthesizedTypes(node.parent);
+                switch (parent.kind) {
+                    case 232 /* VariableDeclaration */:
+                        var decl = parent;
+                        if (decl.name.kind !== 71 /* Identifier */) {
+                            return grammarErrorOnNode(node, ts.Diagnostics.unique_symbol_types_may_not_be_used_on_a_variable_declaration_with_a_binding_name);
+                        }
+                        if (!ts.isVariableDeclarationInVariableStatement(decl)) {
+                            return grammarErrorOnNode(node, ts.Diagnostics.unique_symbol_types_are_only_allowed_on_variables_in_a_variable_statement);
+                        }
+                        if (!(decl.parent.flags & 2 /* Const */)) {
+                            return grammarErrorOnNode(parent.name, ts.Diagnostics.A_variable_whose_type_is_a_unique_symbol_type_must_be_const);
+                        }
+                        break;
+                    case 152 /* PropertyDeclaration */:
+                        if (!ts.hasModifier(parent, 32 /* Static */) ||
+                            !ts.hasModifier(parent, 64 /* Readonly */)) {
+                            return grammarErrorOnNode(parent.name, ts.Diagnostics.A_property_of_a_class_whose_type_is_a_unique_symbol_type_must_be_both_static_and_readonly);
+                        }
+                        break;
+                    case 151 /* PropertySignature */:
+                        if (!ts.hasModifier(parent, 64 /* Readonly */)) {
+                            return grammarErrorOnNode(parent.name, ts.Diagnostics.A_property_of_an_interface_or_type_literal_whose_type_is_a_unique_symbol_type_must_be_readonly);
+                        }
+                        break;
+                    default:
+                        return grammarErrorOnNode(node, ts.Diagnostics.unique_symbol_types_are_not_allowed_here);
+                }
+            }
+        }
+        function checkGrammarForInvalidDynamicName(node, message) {
+            if (isNonBindableDynamicName(node)) {
+                return grammarErrorOnNode(node, message);
+            }
+        }
+        function checkGrammarMethod(node) {
+            if (checkGrammarFunctionLikeDeclaration(node)) {
+                return true;
+            }
+            if (node.kind === 154 /* MethodDeclaration */) {
+                if (node.parent.kind === 184 /* ObjectLiteralExpression */) {
+                    // We only disallow modifier on a method declaration if it is a property of object-literal-expression
+                    if (node.modifiers && !(node.modifiers.length === 1 && ts.first(node.modifiers).kind === 120 /* AsyncKeyword */)) {
+                        return grammarErrorOnFirstToken(node, ts.Diagnostics.Modifiers_cannot_appear_here);
+                    }
+                    else if (checkGrammarForInvalidQuestionMark(node.questionToken, ts.Diagnostics.An_object_member_cannot_be_declared_optional)) {
+                        return true;
+                    }
+                    else if (node.body === undefined) {
+                        return grammarErrorAtPos(node, node.end - 1, ";".length, ts.Diagnostics._0_expected, "{");
+                    }
+                }
+                if (checkGrammarForGenerator(node)) {
+                    return true;
+                }
+            }
+            if (ts.isClassLike(node.parent)) {
+                // Technically, computed properties in ambient contexts is disallowed
+                // for property declarations and accessors too, not just methods.
+                // However, property declarations disallow computed names in general,
+                // and accessors are not allowed in ambient contexts in general,
+                // so this error only really matters for methods.
+                if (node.flags & 4194304 /* Ambient */) {
+                    return checkGrammarForInvalidDynamicName(node.name, ts.Diagnostics.A_computed_property_name_in_an_ambient_context_must_refer_to_an_expression_whose_type_is_a_literal_type_or_a_unique_symbol_type);
+                }
+                else if (node.kind === 154 /* MethodDeclaration */ && !node.body) {
+                    return checkGrammarForInvalidDynamicName(node.name, ts.Diagnostics.A_computed_property_name_in_a_method_overload_must_refer_to_an_expression_whose_type_is_a_literal_type_or_a_unique_symbol_type);
+                }
+            }
+            else if (node.parent.kind === 236 /* InterfaceDeclaration */) {
+                return checkGrammarForInvalidDynamicName(node.name, ts.Diagnostics.A_computed_property_name_in_an_interface_must_refer_to_an_expression_whose_type_is_a_literal_type_or_a_unique_symbol_type);
+            }
+            else if (node.parent.kind === 166 /* TypeLiteral */) {
+                return checkGrammarForInvalidDynamicName(node.name, ts.Diagnostics.A_computed_property_name_in_a_type_literal_must_refer_to_an_expression_whose_type_is_a_literal_type_or_a_unique_symbol_type);
+            }
+        }
+        function checkGrammarBreakOrContinueStatement(node) {
+            var current = node;
+            while (current) {
+                if (ts.isFunctionLike(current)) {
+                    return grammarErrorOnNode(node, ts.Diagnostics.Jump_target_cannot_cross_function_boundary);
+                }
+                switch (current.kind) {
+                    case 228 /* LabeledStatement */:
+                        if (node.label && current.label.escapedText === node.label.escapedText) {
+                            // found matching label - verify that label usage is correct
+                            // continue can only target labels that are on iteration statements
+                            var isMisplacedContinueLabel = node.kind === 223 /* ContinueStatement */
+                                && !ts.isIterationStatement(current.statement, /*lookInLabeledStatement*/ true);
+                            if (isMisplacedContinueLabel) {
+                                return grammarErrorOnNode(node, ts.Diagnostics.A_continue_statement_can_only_jump_to_a_label_of_an_enclosing_iteration_statement);
+                            }
+                            return false;
+                        }
+                        break;
+                    case 227 /* SwitchStatement */:
+                        if (node.kind === 224 /* BreakStatement */ && !node.label) {
+                            // unlabeled break within switch statement - ok
+                            return false;
+                        }
+                        break;
+                    default:
+                        if (ts.isIterationStatement(current, /*lookInLabeledStatement*/ false) && !node.label) {
+                            // unlabeled break or continue within iteration statement - ok
+                            return false;
+                        }
+                        break;
+                }
+                current = current.parent;
+            }
+            if (node.label) {
+                var message = node.kind === 224 /* BreakStatement */
+                    ? ts.Diagnostics.A_break_statement_can_only_jump_to_a_label_of_an_enclosing_statement
+                    : ts.Diagnostics.A_continue_statement_can_only_jump_to_a_label_of_an_enclosing_iteration_statement;
+                return grammarErrorOnNode(node, message);
+            }
+            else {
+                var message = node.kind === 224 /* BreakStatement */
+                    ? ts.Diagnostics.A_break_statement_can_only_be_used_within_an_enclosing_iteration_or_switch_statement
+                    : ts.Diagnostics.A_continue_statement_can_only_be_used_within_an_enclosing_iteration_statement;
+                return grammarErrorOnNode(node, message);
+            }
+        }
+        function checkGrammarBindingElement(node) {
+            if (node.dotDotDotToken) {
+                var elements = node.parent.elements;
+                if (node !== ts.last(elements)) {
+                    return grammarErrorOnNode(node, ts.Diagnostics.A_rest_element_must_be_last_in_a_destructuring_pattern);
+                }
+                checkGrammarForDisallowedTrailingComma(elements, ts.Diagnostics.A_rest_parameter_or_binding_pattern_may_not_have_a_trailing_comma);
+                if (node.name.kind === 181 /* ArrayBindingPattern */ || node.name.kind === 180 /* ObjectBindingPattern */) {
+                    return grammarErrorOnNode(node.name, ts.Diagnostics.A_rest_element_cannot_contain_a_binding_pattern);
+                }
+                if (node.propertyName) {
+                    return grammarErrorOnNode(node.name, ts.Diagnostics.A_rest_element_cannot_have_a_property_name);
+                }
+                if (node.initializer) {
+                    // Error on equals token which immediately precedes the initializer
+                    return grammarErrorAtPos(node, node.initializer.pos - 1, 1, ts.Diagnostics.A_rest_element_cannot_have_an_initializer);
+                }
+            }
+        }
+        function isStringOrNumberLiteralExpression(expr) {
+            return expr.kind === 9 /* StringLiteral */ || expr.kind === 8 /* NumericLiteral */ ||
+                expr.kind === 198 /* PrefixUnaryExpression */ && expr.operator === 38 /* MinusToken */ &&
+                    expr.operand.kind === 8 /* NumericLiteral */;
+        }
+        function checkGrammarVariableDeclaration(node) {
+            if (node.parent.parent.kind !== 221 /* ForInStatement */ && node.parent.parent.kind !== 222 /* ForOfStatement */) {
+                if (node.flags & 4194304 /* Ambient */) {
+                    if (node.initializer) {
+                        if (ts.isConst(node) && !node.type) {
+                            if (!isStringOrNumberLiteralExpression(node.initializer)) {
+                                return grammarErrorOnNode(node.initializer, ts.Diagnostics.A_const_initializer_in_an_ambient_context_must_be_a_string_or_numeric_literal);
+                            }
+                        }
+                        else {
+                            // Error on equals token which immediate precedes the initializer
+                            var equalsTokenLength = "=".length;
+                            return grammarErrorAtPos(node, node.initializer.pos - equalsTokenLength, equalsTokenLength, ts.Diagnostics.Initializers_are_not_allowed_in_ambient_contexts);
+                        }
+                    }
+                    if (node.initializer && !(ts.isConst(node) && isStringOrNumberLiteralExpression(node.initializer))) {
+                        // Error on equals token which immediate precedes the initializer
+                        var equalsTokenLength = "=".length;
+                        return grammarErrorAtPos(node, node.initializer.pos - equalsTokenLength, equalsTokenLength, ts.Diagnostics.Initializers_are_not_allowed_in_ambient_contexts);
+                    }
+                }
+                else if (!node.initializer) {
+                    if (ts.isBindingPattern(node.name) && !ts.isBindingPattern(node.parent)) {
+                        return grammarErrorOnNode(node, ts.Diagnostics.A_destructuring_declaration_must_have_an_initializer);
+                    }
+                    if (ts.isConst(node)) {
+                        return grammarErrorOnNode(node, ts.Diagnostics.const_declarations_must_be_initialized);
+                    }
+                }
+            }
+            if (node.exclamationToken && (node.parent.parent.kind !== 214 /* VariableStatement */ || !node.type || node.initializer || node.flags & 4194304 /* Ambient */)) {
+                return grammarErrorOnNode(node.exclamationToken, ts.Diagnostics.A_definite_assignment_assertion_is_not_permitted_in_this_context);
+            }
+            if (compilerOptions.module !== ts.ModuleKind.ES2015 && compilerOptions.module !== ts.ModuleKind.ESNext && compilerOptions.module !== ts.ModuleKind.System && !compilerOptions.noEmit &&
+                !(node.parent.parent.flags & 4194304 /* Ambient */) && ts.hasModifier(node.parent.parent, 1 /* Export */)) {
+                checkESModuleMarker(node.name);
+            }
+            var checkLetConstNames = (ts.isLet(node) || ts.isConst(node));
+            // 1. LexicalDeclaration : LetOrConst BindingList ;
+            // It is a Syntax Error if the BoundNames of BindingList contains "let".
+            // 2. ForDeclaration: ForDeclaration : LetOrConst ForBinding
+            // It is a Syntax Error if the BoundNames of ForDeclaration contains "let".
+            // It is a SyntaxError if a VariableDeclaration or VariableDeclarationNoIn occurs within strict code
+            // and its Identifier is eval or arguments
+            return checkLetConstNames && checkGrammarNameInLetOrConstDeclarations(node.name);
+        }
+        function checkESModuleMarker(name) {
+            if (name.kind === 71 /* Identifier */) {
+                if (ts.idText(name) === "__esModule") {
+                    return grammarErrorOnNode(name, ts.Diagnostics.Identifier_expected_esModule_is_reserved_as_an_exported_marker_when_transforming_ECMAScript_modules);
+                }
+            }
+            else {
+                var elements = name.elements;
+                for (var _i = 0, elements_1 = elements; _i < elements_1.length; _i++) {
+                    var element = elements_1[_i];
+                    if (!ts.isOmittedExpression(element)) {
+                        return checkESModuleMarker(element.name);
+                    }
+                }
+            }
+            return false;
+        }
+        function checkGrammarNameInLetOrConstDeclarations(name) {
+            if (name.kind === 71 /* Identifier */) {
+                if (name.originalKeywordKind === 110 /* LetKeyword */) {
+                    return grammarErrorOnNode(name, ts.Diagnostics.let_is_not_allowed_to_be_used_as_a_name_in_let_or_const_declarations);
+                }
+            }
+            else {
+                var elements = name.elements;
+                for (var _i = 0, elements_2 = elements; _i < elements_2.length; _i++) {
+                    var element = elements_2[_i];
+                    if (!ts.isOmittedExpression(element)) {
+                        checkGrammarNameInLetOrConstDeclarations(element.name);
+                    }
+                }
+            }
+            return false;
+        }
+        function checkGrammarVariableDeclarationList(declarationList) {
+            var declarations = declarationList.declarations;
+            if (checkGrammarForDisallowedTrailingComma(declarationList.declarations)) {
+                return true;
+            }
+            if (!declarationList.declarations.length) {
+                return grammarErrorAtPos(declarationList, declarations.pos, declarations.end - declarations.pos, ts.Diagnostics.Variable_declaration_list_cannot_be_empty);
+            }
+            return false;
+        }
+        function allowLetAndConstDeclarations(parent) {
+            switch (parent.kind) {
+                case 217 /* IfStatement */:
+                case 218 /* DoStatement */:
+                case 219 /* WhileStatement */:
+                case 226 /* WithStatement */:
+                case 220 /* ForStatement */:
+                case 221 /* ForInStatement */:
+                case 222 /* ForOfStatement */:
+                    return false;
+                case 228 /* LabeledStatement */:
+                    return allowLetAndConstDeclarations(parent.parent);
+            }
+            return true;
+        }
+        function checkGrammarForDisallowedLetOrConstStatement(node) {
+            if (!allowLetAndConstDeclarations(node.parent)) {
+                if (ts.isLet(node.declarationList)) {
+                    return grammarErrorOnNode(node, ts.Diagnostics.let_declarations_can_only_be_declared_inside_a_block);
+                }
+                else if (ts.isConst(node.declarationList)) {
+                    return grammarErrorOnNode(node, ts.Diagnostics.const_declarations_can_only_be_declared_inside_a_block);
+                }
+            }
+        }
+        function checkGrammarMetaProperty(node) {
+            var escapedText = node.name.escapedText;
+            switch (node.keywordToken) {
+                case 94 /* NewKeyword */:
+                    if (escapedText !== "target") {
+                        return grammarErrorOnNode(node.name, ts.Diagnostics._0_is_not_a_valid_meta_property_for_keyword_1_Did_you_mean_2, node.name.escapedText, ts.tokenToString(node.keywordToken), "target");
+                    }
+                    break;
+                case 91 /* ImportKeyword */:
+                    if (escapedText !== "meta") {
+                        return grammarErrorOnNode(node.name, ts.Diagnostics._0_is_not_a_valid_meta_property_for_keyword_1_Did_you_mean_2, node.name.escapedText, ts.tokenToString(node.keywordToken), "meta");
+                    }
+                    break;
+            }
+        }
+        function hasParseDiagnostics(sourceFile) {
+            return sourceFile.parseDiagnostics.length > 0;
+        }
+        function grammarErrorOnFirstToken(node, message, arg0, arg1, arg2) {
+            var sourceFile = ts.getSourceFileOfNode(node);
+            if (!hasParseDiagnostics(sourceFile)) {
+                var span = ts.getSpanOfTokenAtPosition(sourceFile, node.pos);
+                diagnostics.add(ts.createFileDiagnostic(sourceFile, span.start, span.length, message, arg0, arg1, arg2));
+                return true;
+            }
+            return false;
+        }
+        function grammarErrorAtPos(nodeForSourceFile, start, length, message, arg0, arg1, arg2) {
+            var sourceFile = ts.getSourceFileOfNode(nodeForSourceFile);
+            if (!hasParseDiagnostics(sourceFile)) {
+                diagnostics.add(ts.createFileDiagnostic(sourceFile, start, length, message, arg0, arg1, arg2));
+                return true;
+            }
+            return false;
+        }
+        function grammarErrorOnNode(node, message, arg0, arg1, arg2) {
+            var sourceFile = ts.getSourceFileOfNode(node);
+            if (!hasParseDiagnostics(sourceFile)) {
+                diagnostics.add(ts.createDiagnosticForNode(node, message, arg0, arg1, arg2));
+                return true;
+            }
+            return false;
+        }
+        function checkGrammarConstructorTypeParameters(node) {
+            var jsdocTypeParameters = ts.isInJavaScriptFile(node) && ts.getJSDocTypeParameterDeclarations(node);
+            if (node.typeParameters || jsdocTypeParameters && jsdocTypeParameters.length) {
+                var _a = node.typeParameters || jsdocTypeParameters && jsdocTypeParameters[0] || node, pos = _a.pos, end = _a.end;
+                return grammarErrorAtPos(node, pos, end - pos, ts.Diagnostics.Type_parameters_cannot_appear_on_a_constructor_declaration);
+            }
+        }
+        function checkGrammarConstructorTypeAnnotation(node) {
+            var type = ts.getEffectiveReturnTypeNode(node);
+            if (type) {
+                return grammarErrorOnNode(type, ts.Diagnostics.Type_annotation_cannot_appear_on_a_constructor_declaration);
+            }
+        }
+        function checkGrammarProperty(node) {
+            if (ts.isClassLike(node.parent)) {
+                if (checkGrammarForInvalidDynamicName(node.name, ts.Diagnostics.A_computed_property_name_in_a_class_property_declaration_must_refer_to_an_expression_whose_type_is_a_literal_type_or_a_unique_symbol_type)) {
+                    return true;
+                }
+            }
+            else if (node.parent.kind === 236 /* InterfaceDeclaration */) {
+                if (checkGrammarForInvalidDynamicName(node.name, ts.Diagnostics.A_computed_property_name_in_an_interface_must_refer_to_an_expression_whose_type_is_a_literal_type_or_a_unique_symbol_type)) {
+                    return true;
+                }
+                if (node.initializer) {
+                    return grammarErrorOnNode(node.initializer, ts.Diagnostics.An_interface_property_cannot_have_an_initializer);
+                }
+            }
+            else if (node.parent.kind === 166 /* TypeLiteral */) {
+                if (checkGrammarForInvalidDynamicName(node.name, ts.Diagnostics.A_computed_property_name_in_a_type_literal_must_refer_to_an_expression_whose_type_is_a_literal_type_or_a_unique_symbol_type)) {
+                    return true;
+                }
+                if (node.initializer) {
+                    return grammarErrorOnNode(node.initializer, ts.Diagnostics.A_type_literal_property_cannot_have_an_initializer);
+                }
+            }
+            if (node.flags & 4194304 /* Ambient */ && node.initializer) {
+                return grammarErrorOnFirstToken(node.initializer, ts.Diagnostics.Initializers_are_not_allowed_in_ambient_contexts);
+            }
+            if (ts.isPropertyDeclaration(node) && node.exclamationToken && (!ts.isClassLike(node.parent) || !node.type || node.initializer ||
+                node.flags & 4194304 /* Ambient */ || ts.hasModifier(node, 32 /* Static */ | 128 /* Abstract */))) {
+                return grammarErrorOnNode(node.exclamationToken, ts.Diagnostics.A_definite_assignment_assertion_is_not_permitted_in_this_context);
+            }
+        }
+        function checkGrammarTopLevelElementForRequiredDeclareModifier(node) {
+            // A declare modifier is required for any top level .d.ts declaration except export=, export default, export as namespace
+            // interfaces and imports categories:
+            //
+            //  DeclarationElement:
+            //     ExportAssignment
+            //     export_opt   InterfaceDeclaration
+            //     export_opt   TypeAliasDeclaration
+            //     export_opt   ImportDeclaration
+            //     export_opt   ExternalImportDeclaration
+            //     export_opt   AmbientDeclaration
+            //
+            // TODO: The spec needs to be amended to reflect this grammar.
+            if (node.kind === 236 /* InterfaceDeclaration */ ||
+                node.kind === 237 /* TypeAliasDeclaration */ ||
+                node.kind === 244 /* ImportDeclaration */ ||
+                node.kind === 243 /* ImportEqualsDeclaration */ ||
+                node.kind === 250 /* ExportDeclaration */ ||
+                node.kind === 249 /* ExportAssignment */ ||
+                node.kind === 242 /* NamespaceExportDeclaration */ ||
+                ts.hasModifier(node, 2 /* Ambient */ | 1 /* Export */ | 512 /* Default */)) {
+                return false;
+            }
+            return grammarErrorOnFirstToken(node, ts.Diagnostics.A_declare_modifier_is_required_for_a_top_level_declaration_in_a_d_ts_file);
+        }
+        function checkGrammarTopLevelElementsForRequiredDeclareModifier(file) {
+            for (var _i = 0, _a = file.statements; _i < _a.length; _i++) {
+                var decl = _a[_i];
+                if (ts.isDeclaration(decl) || decl.kind === 214 /* VariableStatement */) {
+                    if (checkGrammarTopLevelElementForRequiredDeclareModifier(decl)) {
+                        return true;
+                    }
+                }
+            }
+            return false;
+        }
+        function checkGrammarSourceFile(node) {
+            return !!(node.flags & 4194304 /* Ambient */) && checkGrammarTopLevelElementsForRequiredDeclareModifier(node);
+        }
+        function checkGrammarStatementInAmbientContext(node) {
+            if (node.flags & 4194304 /* Ambient */) {
+                // An accessors is already reported about the ambient context
+                if (ts.isAccessor(node.parent)) {
+                    return getNodeLinks(node).hasReportedStatementInAmbientContext = true;
+                }
+                // Find containing block which is either Block, ModuleBlock, SourceFile
+                var links = getNodeLinks(node);
+                if (!links.hasReportedStatementInAmbientContext && ts.isFunctionLike(node.parent)) {
+                    return getNodeLinks(node).hasReportedStatementInAmbientContext = grammarErrorOnFirstToken(node, ts.Diagnostics.An_implementation_cannot_be_declared_in_ambient_contexts);
+                }
+                // We are either parented by another statement, or some sort of block.
+                // If we're in a block, we only want to really report an error once
+                // to prevent noisiness.  So use a bit on the block to indicate if
+                // this has already been reported, and don't report if it has.
+                //
+                if (node.parent.kind === 213 /* Block */ || node.parent.kind === 240 /* ModuleBlock */ || node.parent.kind === 274 /* SourceFile */) {
+                    var links_1 = getNodeLinks(node.parent);
+                    // Check if the containing block ever report this error
+                    if (!links_1.hasReportedStatementInAmbientContext) {
+                        return links_1.hasReportedStatementInAmbientContext = grammarErrorOnFirstToken(node, ts.Diagnostics.Statements_are_not_allowed_in_ambient_contexts);
+                    }
+                }
+                else {
+                    // We must be parented by a statement.  If so, there's no need
+                    // to report the error as our parent will have already done it.
+                    // Debug.assert(isStatement(node.parent));
+                }
+            }
+            return false;
+        }
+        function checkGrammarNumericLiteral(node) {
+            // Grammar checking
+            if (node.numericLiteralFlags & 32 /* Octal */) {
+                var diagnosticMessage = void 0;
+                if (languageVersion >= 1 /* ES5 */) {
+                    diagnosticMessage = ts.Diagnostics.Octal_literals_are_not_available_when_targeting_ECMAScript_5_and_higher_Use_the_syntax_0;
+                }
+                else if (ts.isChildOfNodeWithKind(node, 178 /* LiteralType */)) {
+                    diagnosticMessage = ts.Diagnostics.Octal_literal_types_must_use_ES2015_syntax_Use_the_syntax_0;
+                }
+                else if (ts.isChildOfNodeWithKind(node, 273 /* EnumMember */)) {
+                    diagnosticMessage = ts.Diagnostics.Octal_literals_are_not_allowed_in_enums_members_initializer_Use_the_syntax_0;
+                }
+                if (diagnosticMessage) {
+                    var withMinus = ts.isPrefixUnaryExpression(node.parent) && node.parent.operator === 38 /* MinusToken */;
+                    var literal = (withMinus ? "-" : "") + "0o" + node.text;
+                    return grammarErrorOnNode(withMinus ? node.parent : node, diagnosticMessage, literal);
+                }
+            }
+            return false;
+        }
+        function grammarErrorAfterFirstToken(node, message, arg0, arg1, arg2) {
+            var sourceFile = ts.getSourceFileOfNode(node);
+            if (!hasParseDiagnostics(sourceFile)) {
+                var span = ts.getSpanOfTokenAtPosition(sourceFile, node.pos);
+                diagnostics.add(ts.createFileDiagnostic(sourceFile, ts.textSpanEnd(span), /*length*/ 0, message, arg0, arg1, arg2));
+                return true;
+            }
+            return false;
+        }
+        function getAmbientModules() {
+            if (!ambientModulesCache) {
+                ambientModulesCache = [];
+                globals.forEach(function (global, sym) {
+                    // No need to `unescapeLeadingUnderscores`, an escaped symbol is never an ambient module.
+                    if (ambientModuleSymbolRegex.test(sym)) {
+                        ambientModulesCache.push(global);
+                    }
+                });
+            }
+            return ambientModulesCache;
+        }
+        function checkGrammarImportCallExpression(node) {
+            if (moduleKind === ts.ModuleKind.ES2015) {
+                return grammarErrorOnNode(node, ts.Diagnostics.Dynamic_import_is_only_supported_when_module_flag_is_commonjs_or_esNext);
+            }
+            if (node.typeArguments) {
+                return grammarErrorOnNode(node, ts.Diagnostics.Dynamic_import_cannot_have_type_arguments);
+            }
+            var nodeArguments = node.arguments;
+            if (nodeArguments.length !== 1) {
+                return grammarErrorOnNode(node, ts.Diagnostics.Dynamic_import_must_have_one_specifier_as_an_argument);
+            }
+            // see: parseArgumentOrArrayLiteralElement...we use this function which parse arguments of callExpression to parse specifier for dynamic import.
+            // parseArgumentOrArrayLiteralElement allows spread element to be in an argument list which is not allowed as specifier in dynamic import.
+            if (ts.isSpreadElement(nodeArguments[0])) {
+                return grammarErrorOnNode(nodeArguments[0], ts.Diagnostics.Specifier_of_dynamic_import_cannot_be_spread_element);
+            }
+            return false;
+        }
+    }
+    ts.createTypeChecker = createTypeChecker;
+    /** Like 'isDeclarationName', but returns true for LHS of `import { x as y }` or `export { x as y }`. */
+    function isDeclarationNameOrImportPropertyName(name) {
+        switch (name.parent.kind) {
+            case 248 /* ImportSpecifier */:
+            case 252 /* ExportSpecifier */:
+                return ts.isIdentifier(name);
+            default:
+                return ts.isDeclarationName(name);
+        }
+    }
+    function isSomeImportDeclaration(decl) {
+        switch (decl.kind) {
+            case 245 /* ImportClause */: // For default import
+            case 243 /* ImportEqualsDeclaration */:
+            case 246 /* NamespaceImport */:
+            case 248 /* ImportSpecifier */: // For rename import `x as y`
+                return true;
+            case 71 /* Identifier */:
+                // For regular import, `decl` is an Identifier under the ImportSpecifier.
+                return decl.parent.kind === 248 /* ImportSpecifier */;
+            default:
+                return false;
+        }
+    }
+    var JsxNames;
+    (function (JsxNames) {
+        // tslint:disable variable-name
+        JsxNames.JSX = "JSX";
+        JsxNames.IntrinsicElements = "IntrinsicElements";
+        JsxNames.ElementClass = "ElementClass";
+        JsxNames.ElementAttributesPropertyNameContainer = "ElementAttributesProperty"; // TODO: Deprecate and remove support
+        JsxNames.ElementChildrenAttributeNameContainer = "ElementChildrenAttribute";
+        JsxNames.Element = "Element";
+        JsxNames.IntrinsicAttributes = "IntrinsicAttributes";
+        JsxNames.IntrinsicClassAttributes = "IntrinsicClassAttributes";
+        // tslint:enable variable-name
+    })(JsxNames || (JsxNames = {}));
+})(ts || (ts = {}));
+var ts;
+(function (ts) {
+    function createSynthesizedNode(kind) {
+        var node = ts.createNode(kind, -1, -1);
+        node.flags |= 8 /* Synthesized */;
+        return node;
+    }
+    /* @internal */
+    function updateNode(updated, original) {
+        if (updated !== original) {
+            setOriginalNode(updated, original);
+            setTextRange(updated, original);
+            ts.aggregateTransformFlags(updated);
+        }
+        return updated;
+    }
+    ts.updateNode = updateNode;
+    /**
+     * Make `elements` into a `NodeArray<T>`. If `elements` is `undefined`, returns an empty `NodeArray<T>`.
+     */
+    function createNodeArray(elements, hasTrailingComma) {
+        if (!elements || elements === ts.emptyArray) {
+            elements = [];
+        }
+        else if (ts.isNodeArray(elements)) {
+            return elements;
+        }
+        var array = elements;
+        array.pos = -1;
+        array.end = -1;
+        array.hasTrailingComma = hasTrailingComma;
+        return array;
+    }
+    ts.createNodeArray = createNodeArray;
+    /**
+     * Creates a shallow, memberwise clone of a node with no source map location.
+     */
+    /* @internal */
+    function getSynthesizedClone(node) {
+        // We don't use "clone" from core.ts here, as we need to preserve the prototype chain of
+        // the original node. We also need to exclude specific properties and only include own-
+        // properties (to skip members already defined on the shared prototype).
+        if (node === undefined) {
+            return node;
+        }
+        var clone = createSynthesizedNode(node.kind);
+        clone.flags |= node.flags;
+        setOriginalNode(clone, node);
+        for (var key in node) {
+            if (clone.hasOwnProperty(key) || !node.hasOwnProperty(key)) {
+                continue;
+            }
+            clone[key] = node[key];
+        }
+        return clone;
+    }
+    ts.getSynthesizedClone = getSynthesizedClone;
+    function createLiteral(value, isSingleQuote) {
+        if (typeof value === "number") {
+            return createNumericLiteral(value + "");
+        }
+        if (typeof value === "boolean") {
+            return value ? createTrue() : createFalse();
+        }
+        if (ts.isString(value)) {
+            var res = createStringLiteral(value);
+            if (isSingleQuote)
+                res.singleQuote = true;
+            return res;
+        }
+        return createLiteralFromNode(value);
+    }
+    ts.createLiteral = createLiteral;
+    function createNumericLiteral(value) {
+        var node = createSynthesizedNode(8 /* NumericLiteral */);
+        node.text = value;
+        node.numericLiteralFlags = 0;
+        return node;
+    }
+    ts.createNumericLiteral = createNumericLiteral;
+    function createStringLiteral(text) {
+        var node = createSynthesizedNode(9 /* StringLiteral */);
+        node.text = text;
+        return node;
+    }
+    ts.createStringLiteral = createStringLiteral;
+    function createRegularExpressionLiteral(text) {
+        var node = createSynthesizedNode(12 /* RegularExpressionLiteral */);
+        node.text = text;
+        return node;
+    }
+    ts.createRegularExpressionLiteral = createRegularExpressionLiteral;
+    function createLiteralFromNode(sourceNode) {
+        var node = createStringLiteral(ts.getTextOfIdentifierOrLiteral(sourceNode));
+        node.textSourceNode = sourceNode;
+        return node;
+    }
+    function createIdentifier(text, typeArguments) {
+        var node = createSynthesizedNode(71 /* Identifier */);
+        node.escapedText = ts.escapeLeadingUnderscores(text);
+        node.originalKeywordKind = text ? ts.stringToToken(text) : 0 /* Unknown */;
+        node.autoGenerateFlags = 0 /* None */;
+        node.autoGenerateId = 0;
+        if (typeArguments) {
+            node.typeArguments = createNodeArray(typeArguments);
+        }
+        return node;
+    }
+    ts.createIdentifier = createIdentifier;
+    function updateIdentifier(node, typeArguments) {
+        return node.typeArguments !== typeArguments
+            ? updateNode(createIdentifier(ts.idText(node), typeArguments), node)
+            : node;
+    }
+    ts.updateIdentifier = updateIdentifier;
+    var nextAutoGenerateId = 0;
+    function createTempVariable(recordTempVariable, reservedInNestedScopes) {
+        var name = createIdentifier("");
+        name.autoGenerateFlags = 1 /* Auto */;
+        name.autoGenerateId = nextAutoGenerateId;
+        nextAutoGenerateId++;
+        if (recordTempVariable) {
+            recordTempVariable(name);
+        }
+        if (reservedInNestedScopes) {
+            name.autoGenerateFlags |= 8 /* ReservedInNestedScopes */;
+        }
+        return name;
+    }
+    ts.createTempVariable = createTempVariable;
+    /** Create a unique temporary variable for use in a loop. */
+    function createLoopVariable() {
+        var name = createIdentifier("");
+        name.autoGenerateFlags = 2 /* Loop */;
+        name.autoGenerateId = nextAutoGenerateId;
+        nextAutoGenerateId++;
+        return name;
+    }
+    ts.createLoopVariable = createLoopVariable;
+    /** Create a unique name based on the supplied text. */
+    function createUniqueName(text) {
+        var name = createIdentifier(text);
+        name.autoGenerateFlags = 3 /* Unique */;
+        name.autoGenerateId = nextAutoGenerateId;
+        nextAutoGenerateId++;
+        return name;
+    }
+    ts.createUniqueName = createUniqueName;
+    function createOptimisticUniqueName(text) {
+        var name = createIdentifier(text);
+        name.autoGenerateFlags = 3 /* Unique */ | 16 /* Optimistic */;
+        name.autoGenerateId = nextAutoGenerateId;
+        nextAutoGenerateId++;
+        return name;
+    }
+    ts.createOptimisticUniqueName = createOptimisticUniqueName;
+    /** Create a unique name based on the supplied text. This does not consider names injected by the transformer. */
+    function createFileLevelUniqueName(text) {
+        var name = createOptimisticUniqueName(text);
+        name.autoGenerateFlags |= 32 /* FileLevel */;
+        return name;
+    }
+    ts.createFileLevelUniqueName = createFileLevelUniqueName;
+    function getGeneratedNameForNode(node, flags) {
+        var name = createIdentifier(ts.isIdentifier(node) ? ts.idText(node) : "");
+        name.autoGenerateFlags = 4 /* Node */ | flags;
+        name.autoGenerateId = nextAutoGenerateId;
+        name.original = node;
+        nextAutoGenerateId++;
+        return name;
+    }
+    ts.getGeneratedNameForNode = getGeneratedNameForNode;
+    // Punctuation
+    function createToken(token) {
+        return createSynthesizedNode(token);
+    }
+    ts.createToken = createToken;
+    // Reserved words
+    function createSuper() {
+        return createSynthesizedNode(97 /* SuperKeyword */);
+    }
+    ts.createSuper = createSuper;
+    function createThis() {
+        return createSynthesizedNode(99 /* ThisKeyword */);
+    }
+    ts.createThis = createThis;
+    function createNull() {
+        return createSynthesizedNode(95 /* NullKeyword */);
+    }
+    ts.createNull = createNull;
+    function createTrue() {
+        return createSynthesizedNode(101 /* TrueKeyword */);
+    }
+    ts.createTrue = createTrue;
+    function createFalse() {
+        return createSynthesizedNode(86 /* FalseKeyword */);
+    }
+    ts.createFalse = createFalse;
+    // Modifiers
+    function createModifier(kind) {
+        return createToken(kind);
+    }
+    ts.createModifier = createModifier;
+    function createModifiersFromModifierFlags(flags) {
+        var result = [];
+        if (flags & 1 /* Export */) {
+            result.push(createModifier(84 /* ExportKeyword */));
+        }
+        if (flags & 2 /* Ambient */) {
+            result.push(createModifier(124 /* DeclareKeyword */));
+        }
+        if (flags & 512 /* Default */) {
+            result.push(createModifier(79 /* DefaultKeyword */));
+        }
+        if (flags & 2048 /* Const */) {
+            result.push(createModifier(76 /* ConstKeyword */));
+        }
+        if (flags & 4 /* Public */) {
+            result.push(createModifier(114 /* PublicKeyword */));
+        }
+        if (flags & 8 /* Private */) {
+            result.push(createModifier(112 /* PrivateKeyword */));
+        }
+        if (flags & 16 /* Protected */) {
+            result.push(createModifier(113 /* ProtectedKeyword */));
+        }
+        if (flags & 128 /* Abstract */) {
+            result.push(createModifier(117 /* AbstractKeyword */));
+        }
+        if (flags & 32 /* Static */) {
+            result.push(createModifier(115 /* StaticKeyword */));
+        }
+        if (flags & 64 /* Readonly */) {
+            result.push(createModifier(132 /* ReadonlyKeyword */));
+        }
+        if (flags & 256 /* Async */) {
+            result.push(createModifier(120 /* AsyncKeyword */));
+        }
+        return result;
+    }
+    ts.createModifiersFromModifierFlags = createModifiersFromModifierFlags;
+    // Names
+    function createQualifiedName(left, right) {
+        var node = createSynthesizedNode(146 /* QualifiedName */);
+        node.left = left;
+        node.right = asName(right);
+        return node;
+    }
+    ts.createQualifiedName = createQualifiedName;
+    function updateQualifiedName(node, left, right) {
+        return node.left !== left
+            || node.right !== right
+            ? updateNode(createQualifiedName(left, right), node)
+            : node;
+    }
+    ts.updateQualifiedName = updateQualifiedName;
+    function parenthesizeForComputedName(expression) {
+        return (ts.isBinaryExpression(expression) && expression.operatorToken.kind === 26 /* CommaToken */) ||
+            expression.kind === 302 /* CommaListExpression */ ?
+            createParen(expression) :
+            expression;
+    }
+    function createComputedPropertyName(expression) {
+        var node = createSynthesizedNode(147 /* ComputedPropertyName */);
+        node.expression = parenthesizeForComputedName(expression);
+        return node;
+    }
+    ts.createComputedPropertyName = createComputedPropertyName;
+    function updateComputedPropertyName(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createComputedPropertyName(expression), node)
+            : node;
+    }
+    ts.updateComputedPropertyName = updateComputedPropertyName;
+    // Signature elements
+    function createTypeParameterDeclaration(name, constraint, defaultType) {
+        var node = createSynthesizedNode(148 /* TypeParameter */);
+        node.name = asName(name);
+        node.constraint = constraint;
+        node.default = defaultType;
+        return node;
+    }
+    ts.createTypeParameterDeclaration = createTypeParameterDeclaration;
+    function updateTypeParameterDeclaration(node, name, constraint, defaultType) {
+        return node.name !== name
+            || node.constraint !== constraint
+            || node.default !== defaultType
+            ? updateNode(createTypeParameterDeclaration(name, constraint, defaultType), node)
+            : node;
+    }
+    ts.updateTypeParameterDeclaration = updateTypeParameterDeclaration;
+    function createParameter(decorators, modifiers, dotDotDotToken, name, questionToken, type, initializer) {
+        var node = createSynthesizedNode(149 /* Parameter */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.dotDotDotToken = dotDotDotToken;
+        node.name = asName(name);
+        node.questionToken = questionToken;
+        node.type = type;
+        node.initializer = initializer ? ts.parenthesizeExpressionForList(initializer) : undefined;
+        return node;
+    }
+    ts.createParameter = createParameter;
+    function updateParameter(node, decorators, modifiers, dotDotDotToken, name, questionToken, type, initializer) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.dotDotDotToken !== dotDotDotToken
+            || node.name !== name
+            || node.questionToken !== questionToken
+            || node.type !== type
+            || node.initializer !== initializer
+            ? updateNode(createParameter(decorators, modifiers, dotDotDotToken, name, questionToken, type, initializer), node)
+            : node;
+    }
+    ts.updateParameter = updateParameter;
+    function createDecorator(expression) {
+        var node = createSynthesizedNode(150 /* Decorator */);
+        node.expression = ts.parenthesizeForAccess(expression);
+        return node;
+    }
+    ts.createDecorator = createDecorator;
+    function updateDecorator(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createDecorator(expression), node)
+            : node;
+    }
+    ts.updateDecorator = updateDecorator;
+    // Type Elements
+    function createPropertySignature(modifiers, name, questionToken, type, initializer) {
+        var node = createSynthesizedNode(151 /* PropertySignature */);
+        node.modifiers = asNodeArray(modifiers);
+        node.name = asName(name);
+        node.questionToken = questionToken;
+        node.type = type;
+        node.initializer = initializer;
+        return node;
+    }
+    ts.createPropertySignature = createPropertySignature;
+    function updatePropertySignature(node, modifiers, name, questionToken, type, initializer) {
+        return node.modifiers !== modifiers
+            || node.name !== name
+            || node.questionToken !== questionToken
+            || node.type !== type
+            || node.initializer !== initializer
+            ? updateNode(createPropertySignature(modifiers, name, questionToken, type, initializer), node)
+            : node;
+    }
+    ts.updatePropertySignature = updatePropertySignature;
+    function createProperty(decorators, modifiers, name, questionOrExclamationToken, type, initializer) {
+        var node = createSynthesizedNode(152 /* PropertyDeclaration */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.name = asName(name);
+        node.questionToken = questionOrExclamationToken !== undefined && questionOrExclamationToken.kind === 55 /* QuestionToken */ ? questionOrExclamationToken : undefined;
+        node.exclamationToken = questionOrExclamationToken !== undefined && questionOrExclamationToken.kind === 51 /* ExclamationToken */ ? questionOrExclamationToken : undefined;
+        node.type = type;
+        node.initializer = initializer;
+        return node;
+    }
+    ts.createProperty = createProperty;
+    function updateProperty(node, decorators, modifiers, name, questionOrExclamationToken, type, initializer) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.name !== name
+            || node.questionToken !== (questionOrExclamationToken !== undefined && questionOrExclamationToken.kind === 55 /* QuestionToken */ ? questionOrExclamationToken : undefined)
+            || node.exclamationToken !== (questionOrExclamationToken !== undefined && questionOrExclamationToken.kind === 51 /* ExclamationToken */ ? questionOrExclamationToken : undefined)
+            || node.type !== type
+            || node.initializer !== initializer
+            ? updateNode(createProperty(decorators, modifiers, name, questionOrExclamationToken, type, initializer), node)
+            : node;
+    }
+    ts.updateProperty = updateProperty;
+    function createMethodSignature(typeParameters, parameters, type, name, questionToken) {
+        var node = createSignatureDeclaration(153 /* MethodSignature */, typeParameters, parameters, type);
+        node.name = asName(name);
+        node.questionToken = questionToken;
+        return node;
+    }
+    ts.createMethodSignature = createMethodSignature;
+    function updateMethodSignature(node, typeParameters, parameters, type, name, questionToken) {
+        return node.typeParameters !== typeParameters
+            || node.parameters !== parameters
+            || node.type !== type
+            || node.name !== name
+            || node.questionToken !== questionToken
+            ? updateNode(createMethodSignature(typeParameters, parameters, type, name, questionToken), node)
+            : node;
+    }
+    ts.updateMethodSignature = updateMethodSignature;
+    function createMethod(decorators, modifiers, asteriskToken, name, questionToken, typeParameters, parameters, type, body) {
+        var node = createSynthesizedNode(154 /* MethodDeclaration */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.asteriskToken = asteriskToken;
+        node.name = asName(name);
+        node.questionToken = questionToken;
+        node.typeParameters = asNodeArray(typeParameters);
+        node.parameters = createNodeArray(parameters);
+        node.type = type;
+        node.body = body;
+        return node;
+    }
+    ts.createMethod = createMethod;
+    function updateMethod(node, decorators, modifiers, asteriskToken, name, questionToken, typeParameters, parameters, type, body) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.asteriskToken !== asteriskToken
+            || node.name !== name
+            || node.questionToken !== questionToken
+            || node.typeParameters !== typeParameters
+            || node.parameters !== parameters
+            || node.type !== type
+            || node.body !== body
+            ? updateNode(createMethod(decorators, modifiers, asteriskToken, name, questionToken, typeParameters, parameters, type, body), node)
+            : node;
+    }
+    ts.updateMethod = updateMethod;
+    function createConstructor(decorators, modifiers, parameters, body) {
+        var node = createSynthesizedNode(155 /* Constructor */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.typeParameters = undefined;
+        node.parameters = createNodeArray(parameters);
+        node.type = undefined;
+        node.body = body;
+        return node;
+    }
+    ts.createConstructor = createConstructor;
+    function updateConstructor(node, decorators, modifiers, parameters, body) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.parameters !== parameters
+            || node.body !== body
+            ? updateNode(createConstructor(decorators, modifiers, parameters, body), node)
+            : node;
+    }
+    ts.updateConstructor = updateConstructor;
+    function createGetAccessor(decorators, modifiers, name, parameters, type, body) {
+        var node = createSynthesizedNode(156 /* GetAccessor */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.name = asName(name);
+        node.typeParameters = undefined;
+        node.parameters = createNodeArray(parameters);
+        node.type = type;
+        node.body = body;
+        return node;
+    }
+    ts.createGetAccessor = createGetAccessor;
+    function updateGetAccessor(node, decorators, modifiers, name, parameters, type, body) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.name !== name
+            || node.parameters !== parameters
+            || node.type !== type
+            || node.body !== body
+            ? updateNode(createGetAccessor(decorators, modifiers, name, parameters, type, body), node)
+            : node;
+    }
+    ts.updateGetAccessor = updateGetAccessor;
+    function createSetAccessor(decorators, modifiers, name, parameters, body) {
+        var node = createSynthesizedNode(157 /* SetAccessor */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.name = asName(name);
+        node.typeParameters = undefined;
+        node.parameters = createNodeArray(parameters);
+        node.body = body;
+        return node;
+    }
+    ts.createSetAccessor = createSetAccessor;
+    function updateSetAccessor(node, decorators, modifiers, name, parameters, body) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.name !== name
+            || node.parameters !== parameters
+            || node.body !== body
+            ? updateNode(createSetAccessor(decorators, modifiers, name, parameters, body), node)
+            : node;
+    }
+    ts.updateSetAccessor = updateSetAccessor;
+    function createCallSignature(typeParameters, parameters, type) {
+        return createSignatureDeclaration(158 /* CallSignature */, typeParameters, parameters, type);
+    }
+    ts.createCallSignature = createCallSignature;
+    function updateCallSignature(node, typeParameters, parameters, type) {
+        return updateSignatureDeclaration(node, typeParameters, parameters, type);
+    }
+    ts.updateCallSignature = updateCallSignature;
+    function createConstructSignature(typeParameters, parameters, type) {
+        return createSignatureDeclaration(159 /* ConstructSignature */, typeParameters, parameters, type);
+    }
+    ts.createConstructSignature = createConstructSignature;
+    function updateConstructSignature(node, typeParameters, parameters, type) {
+        return updateSignatureDeclaration(node, typeParameters, parameters, type);
+    }
+    ts.updateConstructSignature = updateConstructSignature;
+    function createIndexSignature(decorators, modifiers, parameters, type) {
+        var node = createSynthesizedNode(160 /* IndexSignature */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.parameters = createNodeArray(parameters);
+        node.type = type;
+        return node;
+    }
+    ts.createIndexSignature = createIndexSignature;
+    function updateIndexSignature(node, decorators, modifiers, parameters, type) {
+        return node.parameters !== parameters
+            || node.type !== type
+            || node.decorators !== decorators
+            || node.modifiers !== modifiers
+            ? updateNode(createIndexSignature(decorators, modifiers, parameters, type), node)
+            : node;
+    }
+    ts.updateIndexSignature = updateIndexSignature;
+    /* @internal */
+    function createSignatureDeclaration(kind, typeParameters, parameters, type, typeArguments) {
+        var node = createSynthesizedNode(kind);
+        node.typeParameters = asNodeArray(typeParameters);
+        node.parameters = asNodeArray(parameters);
+        node.type = type;
+        node.typeArguments = asNodeArray(typeArguments);
+        return node;
+    }
+    ts.createSignatureDeclaration = createSignatureDeclaration;
+    function updateSignatureDeclaration(node, typeParameters, parameters, type) {
+        return node.typeParameters !== typeParameters
+            || node.parameters !== parameters
+            || node.type !== type
+            ? updateNode(createSignatureDeclaration(node.kind, typeParameters, parameters, type), node)
+            : node;
+    }
+    // Types
+    function createKeywordTypeNode(kind) {
+        return createSynthesizedNode(kind);
+    }
+    ts.createKeywordTypeNode = createKeywordTypeNode;
+    function createTypePredicateNode(parameterName, type) {
+        var node = createSynthesizedNode(161 /* TypePredicate */);
+        node.parameterName = asName(parameterName);
+        node.type = type;
+        return node;
+    }
+    ts.createTypePredicateNode = createTypePredicateNode;
+    function updateTypePredicateNode(node, parameterName, type) {
+        return node.parameterName !== parameterName
+            || node.type !== type
+            ? updateNode(createTypePredicateNode(parameterName, type), node)
+            : node;
+    }
+    ts.updateTypePredicateNode = updateTypePredicateNode;
+    function createTypeReferenceNode(typeName, typeArguments) {
+        var node = createSynthesizedNode(162 /* TypeReference */);
+        node.typeName = asName(typeName);
+        node.typeArguments = typeArguments && ts.parenthesizeTypeParameters(typeArguments);
+        return node;
+    }
+    ts.createTypeReferenceNode = createTypeReferenceNode;
+    function updateTypeReferenceNode(node, typeName, typeArguments) {
+        return node.typeName !== typeName
+            || node.typeArguments !== typeArguments
+            ? updateNode(createTypeReferenceNode(typeName, typeArguments), node)
+            : node;
+    }
+    ts.updateTypeReferenceNode = updateTypeReferenceNode;
+    function createFunctionTypeNode(typeParameters, parameters, type) {
+        return createSignatureDeclaration(163 /* FunctionType */, typeParameters, parameters, type);
+    }
+    ts.createFunctionTypeNode = createFunctionTypeNode;
+    function updateFunctionTypeNode(node, typeParameters, parameters, type) {
+        return updateSignatureDeclaration(node, typeParameters, parameters, type);
+    }
+    ts.updateFunctionTypeNode = updateFunctionTypeNode;
+    function createConstructorTypeNode(typeParameters, parameters, type) {
+        return createSignatureDeclaration(164 /* ConstructorType */, typeParameters, parameters, type);
+    }
+    ts.createConstructorTypeNode = createConstructorTypeNode;
+    function updateConstructorTypeNode(node, typeParameters, parameters, type) {
+        return updateSignatureDeclaration(node, typeParameters, parameters, type);
+    }
+    ts.updateConstructorTypeNode = updateConstructorTypeNode;
+    function createTypeQueryNode(exprName) {
+        var node = createSynthesizedNode(165 /* TypeQuery */);
+        node.exprName = exprName;
+        return node;
+    }
+    ts.createTypeQueryNode = createTypeQueryNode;
+    function updateTypeQueryNode(node, exprName) {
+        return node.exprName !== exprName
+            ? updateNode(createTypeQueryNode(exprName), node)
+            : node;
+    }
+    ts.updateTypeQueryNode = updateTypeQueryNode;
+    function createTypeLiteralNode(members) {
+        var node = createSynthesizedNode(166 /* TypeLiteral */);
+        node.members = createNodeArray(members);
+        return node;
+    }
+    ts.createTypeLiteralNode = createTypeLiteralNode;
+    function updateTypeLiteralNode(node, members) {
+        return node.members !== members
+            ? updateNode(createTypeLiteralNode(members), node)
+            : node;
+    }
+    ts.updateTypeLiteralNode = updateTypeLiteralNode;
+    function createArrayTypeNode(elementType) {
+        var node = createSynthesizedNode(167 /* ArrayType */);
+        node.elementType = ts.parenthesizeArrayTypeMember(elementType);
+        return node;
+    }
+    ts.createArrayTypeNode = createArrayTypeNode;
+    function updateArrayTypeNode(node, elementType) {
+        return node.elementType !== elementType
+            ? updateNode(createArrayTypeNode(elementType), node)
+            : node;
+    }
+    ts.updateArrayTypeNode = updateArrayTypeNode;
+    function createTupleTypeNode(elementTypes) {
+        var node = createSynthesizedNode(168 /* TupleType */);
+        node.elementTypes = createNodeArray(elementTypes);
+        return node;
+    }
+    ts.createTupleTypeNode = createTupleTypeNode;
+    function updateTypleTypeNode(node, elementTypes) {
+        return node.elementTypes !== elementTypes
+            ? updateNode(createTupleTypeNode(elementTypes), node)
+            : node;
+    }
+    ts.updateTypleTypeNode = updateTypleTypeNode;
+    function createUnionTypeNode(types) {
+        return createUnionOrIntersectionTypeNode(169 /* UnionType */, types);
+    }
+    ts.createUnionTypeNode = createUnionTypeNode;
+    function updateUnionTypeNode(node, types) {
+        return updateUnionOrIntersectionTypeNode(node, types);
+    }
+    ts.updateUnionTypeNode = updateUnionTypeNode;
+    function createIntersectionTypeNode(types) {
+        return createUnionOrIntersectionTypeNode(170 /* IntersectionType */, types);
+    }
+    ts.createIntersectionTypeNode = createIntersectionTypeNode;
+    function updateIntersectionTypeNode(node, types) {
+        return updateUnionOrIntersectionTypeNode(node, types);
+    }
+    ts.updateIntersectionTypeNode = updateIntersectionTypeNode;
+    function createUnionOrIntersectionTypeNode(kind, types) {
+        var node = createSynthesizedNode(kind);
+        node.types = ts.parenthesizeElementTypeMembers(types);
+        return node;
+    }
+    ts.createUnionOrIntersectionTypeNode = createUnionOrIntersectionTypeNode;
+    function updateUnionOrIntersectionTypeNode(node, types) {
+        return node.types !== types
+            ? updateNode(createUnionOrIntersectionTypeNode(node.kind, types), node)
+            : node;
+    }
+    function createConditionalTypeNode(checkType, extendsType, trueType, falseType) {
+        var node = createSynthesizedNode(171 /* ConditionalType */);
+        node.checkType = ts.parenthesizeConditionalTypeMember(checkType);
+        node.extendsType = ts.parenthesizeConditionalTypeMember(extendsType);
+        node.trueType = trueType;
+        node.falseType = falseType;
+        return node;
+    }
+    ts.createConditionalTypeNode = createConditionalTypeNode;
+    function updateConditionalTypeNode(node, checkType, extendsType, trueType, falseType) {
+        return node.checkType !== checkType
+            || node.extendsType !== extendsType
+            || node.trueType !== trueType
+            || node.falseType !== falseType
+            ? updateNode(createConditionalTypeNode(checkType, extendsType, trueType, falseType), node)
+            : node;
+    }
+    ts.updateConditionalTypeNode = updateConditionalTypeNode;
+    function createInferTypeNode(typeParameter) {
+        var node = createSynthesizedNode(172 /* InferType */);
+        node.typeParameter = typeParameter;
+        return node;
+    }
+    ts.createInferTypeNode = createInferTypeNode;
+    function updateInferTypeNode(node, typeParameter) {
+        return node.typeParameter !== typeParameter
+            ? updateNode(createInferTypeNode(typeParameter), node)
+            : node;
+    }
+    ts.updateInferTypeNode = updateInferTypeNode;
+    function createImportTypeNode(argument, qualifier, typeArguments, isTypeOf) {
+        var node = createSynthesizedNode(179 /* ImportType */);
+        node.argument = argument;
+        node.qualifier = qualifier;
+        node.typeArguments = asNodeArray(typeArguments);
+        node.isTypeOf = isTypeOf;
+        return node;
+    }
+    ts.createImportTypeNode = createImportTypeNode;
+    function updateImportTypeNode(node, argument, qualifier, typeArguments, isTypeOf) {
+        return node.argument !== argument
+            || node.qualifier !== qualifier
+            || node.typeArguments !== typeArguments
+            || node.isTypeOf !== isTypeOf
+            ? updateNode(createImportTypeNode(argument, qualifier, typeArguments, isTypeOf), node)
+            : node;
+    }
+    ts.updateImportTypeNode = updateImportTypeNode;
+    function createParenthesizedType(type) {
+        var node = createSynthesizedNode(173 /* ParenthesizedType */);
+        node.type = type;
+        return node;
+    }
+    ts.createParenthesizedType = createParenthesizedType;
+    function updateParenthesizedType(node, type) {
+        return node.type !== type
+            ? updateNode(createParenthesizedType(type), node)
+            : node;
+    }
+    ts.updateParenthesizedType = updateParenthesizedType;
+    function createThisTypeNode() {
+        return createSynthesizedNode(174 /* ThisType */);
+    }
+    ts.createThisTypeNode = createThisTypeNode;
+    function createTypeOperatorNode(operatorOrType, type) {
+        var node = createSynthesizedNode(175 /* TypeOperator */);
+        node.operator = typeof operatorOrType === "number" ? operatorOrType : 128 /* KeyOfKeyword */;
+        node.type = ts.parenthesizeElementTypeMember(typeof operatorOrType === "number" ? type : operatorOrType);
+        return node;
+    }
+    ts.createTypeOperatorNode = createTypeOperatorNode;
+    function updateTypeOperatorNode(node, type) {
+        return node.type !== type ? updateNode(createTypeOperatorNode(node.operator, type), node) : node;
+    }
+    ts.updateTypeOperatorNode = updateTypeOperatorNode;
+    function createIndexedAccessTypeNode(objectType, indexType) {
+        var node = createSynthesizedNode(176 /* IndexedAccessType */);
+        node.objectType = ts.parenthesizeElementTypeMember(objectType);
+        node.indexType = indexType;
+        return node;
+    }
+    ts.createIndexedAccessTypeNode = createIndexedAccessTypeNode;
+    function updateIndexedAccessTypeNode(node, objectType, indexType) {
+        return node.objectType !== objectType
+            || node.indexType !== indexType
+            ? updateNode(createIndexedAccessTypeNode(objectType, indexType), node)
+            : node;
+    }
+    ts.updateIndexedAccessTypeNode = updateIndexedAccessTypeNode;
+    function createMappedTypeNode(readonlyToken, typeParameter, questionToken, type) {
+        var node = createSynthesizedNode(177 /* MappedType */);
+        node.readonlyToken = readonlyToken;
+        node.typeParameter = typeParameter;
+        node.questionToken = questionToken;
+        node.type = type;
+        return node;
+    }
+    ts.createMappedTypeNode = createMappedTypeNode;
+    function updateMappedTypeNode(node, readonlyToken, typeParameter, questionToken, type) {
+        return node.readonlyToken !== readonlyToken
+            || node.typeParameter !== typeParameter
+            || node.questionToken !== questionToken
+            || node.type !== type
+            ? updateNode(createMappedTypeNode(readonlyToken, typeParameter, questionToken, type), node)
+            : node;
+    }
+    ts.updateMappedTypeNode = updateMappedTypeNode;
+    function createLiteralTypeNode(literal) {
+        var node = createSynthesizedNode(178 /* LiteralType */);
+        node.literal = literal;
+        return node;
+    }
+    ts.createLiteralTypeNode = createLiteralTypeNode;
+    function updateLiteralTypeNode(node, literal) {
+        return node.literal !== literal
+            ? updateNode(createLiteralTypeNode(literal), node)
+            : node;
+    }
+    ts.updateLiteralTypeNode = updateLiteralTypeNode;
+    // Binding Patterns
+    function createObjectBindingPattern(elements) {
+        var node = createSynthesizedNode(180 /* ObjectBindingPattern */);
+        node.elements = createNodeArray(elements);
+        return node;
+    }
+    ts.createObjectBindingPattern = createObjectBindingPattern;
+    function updateObjectBindingPattern(node, elements) {
+        return node.elements !== elements
+            ? updateNode(createObjectBindingPattern(elements), node)
+            : node;
+    }
+    ts.updateObjectBindingPattern = updateObjectBindingPattern;
+    function createArrayBindingPattern(elements) {
+        var node = createSynthesizedNode(181 /* ArrayBindingPattern */);
+        node.elements = createNodeArray(elements);
+        return node;
+    }
+    ts.createArrayBindingPattern = createArrayBindingPattern;
+    function updateArrayBindingPattern(node, elements) {
+        return node.elements !== elements
+            ? updateNode(createArrayBindingPattern(elements), node)
+            : node;
+    }
+    ts.updateArrayBindingPattern = updateArrayBindingPattern;
+    function createBindingElement(dotDotDotToken, propertyName, name, initializer) {
+        var node = createSynthesizedNode(182 /* BindingElement */);
+        node.dotDotDotToken = dotDotDotToken;
+        node.propertyName = asName(propertyName);
+        node.name = asName(name);
+        node.initializer = initializer;
+        return node;
+    }
+    ts.createBindingElement = createBindingElement;
+    function updateBindingElement(node, dotDotDotToken, propertyName, name, initializer) {
+        return node.propertyName !== propertyName
+            || node.dotDotDotToken !== dotDotDotToken
+            || node.name !== name
+            || node.initializer !== initializer
+            ? updateNode(createBindingElement(dotDotDotToken, propertyName, name, initializer), node)
+            : node;
+    }
+    ts.updateBindingElement = updateBindingElement;
+    // Expression
+    function createArrayLiteral(elements, multiLine) {
+        var node = createSynthesizedNode(183 /* ArrayLiteralExpression */);
+        node.elements = ts.parenthesizeListElements(createNodeArray(elements));
+        if (multiLine)
+            node.multiLine = true;
+        return node;
+    }
+    ts.createArrayLiteral = createArrayLiteral;
+    function updateArrayLiteral(node, elements) {
+        return node.elements !== elements
+            ? updateNode(createArrayLiteral(elements, node.multiLine), node)
+            : node;
+    }
+    ts.updateArrayLiteral = updateArrayLiteral;
+    function createObjectLiteral(properties, multiLine) {
+        var node = createSynthesizedNode(184 /* ObjectLiteralExpression */);
+        node.properties = createNodeArray(properties);
+        if (multiLine)
+            node.multiLine = true;
+        return node;
+    }
+    ts.createObjectLiteral = createObjectLiteral;
+    function updateObjectLiteral(node, properties) {
+        return node.properties !== properties
+            ? updateNode(createObjectLiteral(properties, node.multiLine), node)
+            : node;
+    }
+    ts.updateObjectLiteral = updateObjectLiteral;
+    function createPropertyAccess(expression, name) {
+        var node = createSynthesizedNode(185 /* PropertyAccessExpression */);
+        node.expression = ts.parenthesizeForAccess(expression);
+        node.name = asName(name); // TODO: GH#18217
+        setEmitFlags(node, 131072 /* NoIndentation */);
+        return node;
+    }
+    ts.createPropertyAccess = createPropertyAccess;
+    function updatePropertyAccess(node, expression, name) {
+        // Because we are updating existed propertyAccess we want to inherit its emitFlags
+        // instead of using the default from createPropertyAccess
+        return node.expression !== expression
+            || node.name !== name
+            ? updateNode(setEmitFlags(createPropertyAccess(expression, name), ts.getEmitFlags(node)), node)
+            : node;
+    }
+    ts.updatePropertyAccess = updatePropertyAccess;
+    function createElementAccess(expression, index) {
+        var node = createSynthesizedNode(186 /* ElementAccessExpression */);
+        node.expression = ts.parenthesizeForAccess(expression);
+        node.argumentExpression = asExpression(index);
+        return node;
+    }
+    ts.createElementAccess = createElementAccess;
+    function updateElementAccess(node, expression, argumentExpression) {
+        return node.expression !== expression
+            || node.argumentExpression !== argumentExpression
+            ? updateNode(createElementAccess(expression, argumentExpression), node)
+            : node;
+    }
+    ts.updateElementAccess = updateElementAccess;
+    function createCall(expression, typeArguments, argumentsArray) {
+        var node = createSynthesizedNode(187 /* CallExpression */);
+        node.expression = ts.parenthesizeForAccess(expression);
+        node.typeArguments = asNodeArray(typeArguments);
+        node.arguments = ts.parenthesizeListElements(createNodeArray(argumentsArray));
+        return node;
+    }
+    ts.createCall = createCall;
+    function updateCall(node, expression, typeArguments, argumentsArray) {
+        return node.expression !== expression
+            || node.typeArguments !== typeArguments
+            || node.arguments !== argumentsArray
+            ? updateNode(createCall(expression, typeArguments, argumentsArray), node)
+            : node;
+    }
+    ts.updateCall = updateCall;
+    function createNew(expression, typeArguments, argumentsArray) {
+        var node = createSynthesizedNode(188 /* NewExpression */);
+        node.expression = ts.parenthesizeForNew(expression);
+        node.typeArguments = asNodeArray(typeArguments);
+        node.arguments = argumentsArray ? ts.parenthesizeListElements(createNodeArray(argumentsArray)) : undefined;
+        return node;
+    }
+    ts.createNew = createNew;
+    function updateNew(node, expression, typeArguments, argumentsArray) {
+        return node.expression !== expression
+            || node.typeArguments !== typeArguments
+            || node.arguments !== argumentsArray
+            ? updateNode(createNew(expression, typeArguments, argumentsArray), node)
+            : node;
+    }
+    ts.updateNew = updateNew;
+    function createTaggedTemplate(tag, typeArgumentsOrTemplate, template) {
+        var node = createSynthesizedNode(189 /* TaggedTemplateExpression */);
+        node.tag = ts.parenthesizeForAccess(tag);
+        if (template) {
+            node.typeArguments = asNodeArray(typeArgumentsOrTemplate);
+            node.template = template;
+        }
+        else {
+            node.typeArguments = undefined;
+            node.template = typeArgumentsOrTemplate;
+        }
+        return node;
+    }
+    ts.createTaggedTemplate = createTaggedTemplate;
+    function updateTaggedTemplate(node, tag, typeArgumentsOrTemplate, template) {
+        return node.tag !== tag
+            || (template
+                ? node.typeArguments !== typeArgumentsOrTemplate || node.template !== template
+                : node.typeArguments !== undefined || node.template !== typeArgumentsOrTemplate)
+            ? updateNode(createTaggedTemplate(tag, typeArgumentsOrTemplate, template), node)
+            : node;
+    }
+    ts.updateTaggedTemplate = updateTaggedTemplate;
+    function createTypeAssertion(type, expression) {
+        var node = createSynthesizedNode(190 /* TypeAssertionExpression */);
+        node.type = type;
+        node.expression = ts.parenthesizePrefixOperand(expression);
+        return node;
+    }
+    ts.createTypeAssertion = createTypeAssertion;
+    function updateTypeAssertion(node, type, expression) {
+        return node.type !== type
+            || node.expression !== expression
+            ? updateNode(createTypeAssertion(type, expression), node)
+            : node;
+    }
+    ts.updateTypeAssertion = updateTypeAssertion;
+    function createParen(expression) {
+        var node = createSynthesizedNode(191 /* ParenthesizedExpression */);
+        node.expression = expression;
+        return node;
+    }
+    ts.createParen = createParen;
+    function updateParen(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createParen(expression), node)
+            : node;
+    }
+    ts.updateParen = updateParen;
+    function createFunctionExpression(modifiers, asteriskToken, name, typeParameters, parameters, type, body) {
+        var node = createSynthesizedNode(192 /* FunctionExpression */);
+        node.modifiers = asNodeArray(modifiers);
+        node.asteriskToken = asteriskToken;
+        node.name = asName(name);
+        node.typeParameters = asNodeArray(typeParameters);
+        node.parameters = createNodeArray(parameters);
+        node.type = type;
+        node.body = body;
+        return node;
+    }
+    ts.createFunctionExpression = createFunctionExpression;
+    function updateFunctionExpression(node, modifiers, asteriskToken, name, typeParameters, parameters, type, body) {
+        return node.name !== name
+            || node.modifiers !== modifiers
+            || node.asteriskToken !== asteriskToken
+            || node.typeParameters !== typeParameters
+            || node.parameters !== parameters
+            || node.type !== type
+            || node.body !== body
+            ? updateNode(createFunctionExpression(modifiers, asteriskToken, name, typeParameters, parameters, type, body), node)
+            : node;
+    }
+    ts.updateFunctionExpression = updateFunctionExpression;
+    function createArrowFunction(modifiers, typeParameters, parameters, type, equalsGreaterThanToken, body) {
+        var node = createSynthesizedNode(193 /* ArrowFunction */);
+        node.modifiers = asNodeArray(modifiers);
+        node.typeParameters = asNodeArray(typeParameters);
+        node.parameters = createNodeArray(parameters);
+        node.type = type;
+        node.equalsGreaterThanToken = equalsGreaterThanToken || createToken(36 /* EqualsGreaterThanToken */);
+        node.body = ts.parenthesizeConciseBody(body);
+        return node;
+    }
+    ts.createArrowFunction = createArrowFunction;
+    function updateArrowFunction(node, modifiers, typeParameters, parameters, type, equalsGreaterThanTokenOrBody, bodyOrUndefined) {
+        var equalsGreaterThanToken;
+        var body;
+        if (bodyOrUndefined === undefined) {
+            equalsGreaterThanToken = node.equalsGreaterThanToken;
+            body = ts.cast(equalsGreaterThanTokenOrBody, ts.isConciseBody);
+        }
+        else {
+            equalsGreaterThanToken = ts.cast(equalsGreaterThanTokenOrBody, function (n) {
+                return n.kind === 36 /* EqualsGreaterThanToken */;
+            });
+            body = bodyOrUndefined;
+        }
+        return node.modifiers !== modifiers
+            || node.typeParameters !== typeParameters
+            || node.parameters !== parameters
+            || node.type !== type
+            || node.equalsGreaterThanToken !== equalsGreaterThanToken
+            || node.body !== body
+            ? updateNode(createArrowFunction(modifiers, typeParameters, parameters, type, equalsGreaterThanToken, body), node)
+            : node;
+    }
+    ts.updateArrowFunction = updateArrowFunction;
+    function createDelete(expression) {
+        var node = createSynthesizedNode(194 /* DeleteExpression */);
+        node.expression = ts.parenthesizePrefixOperand(expression);
+        return node;
+    }
+    ts.createDelete = createDelete;
+    function updateDelete(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createDelete(expression), node)
+            : node;
+    }
+    ts.updateDelete = updateDelete;
+    function createTypeOf(expression) {
+        var node = createSynthesizedNode(195 /* TypeOfExpression */);
+        node.expression = ts.parenthesizePrefixOperand(expression);
+        return node;
+    }
+    ts.createTypeOf = createTypeOf;
+    function updateTypeOf(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createTypeOf(expression), node)
+            : node;
+    }
+    ts.updateTypeOf = updateTypeOf;
+    function createVoid(expression) {
+        var node = createSynthesizedNode(196 /* VoidExpression */);
+        node.expression = ts.parenthesizePrefixOperand(expression);
+        return node;
+    }
+    ts.createVoid = createVoid;
+    function updateVoid(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createVoid(expression), node)
+            : node;
+    }
+    ts.updateVoid = updateVoid;
+    function createAwait(expression) {
+        var node = createSynthesizedNode(197 /* AwaitExpression */);
+        node.expression = ts.parenthesizePrefixOperand(expression);
+        return node;
+    }
+    ts.createAwait = createAwait;
+    function updateAwait(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createAwait(expression), node)
+            : node;
+    }
+    ts.updateAwait = updateAwait;
+    function createPrefix(operator, operand) {
+        var node = createSynthesizedNode(198 /* PrefixUnaryExpression */);
+        node.operator = operator;
+        node.operand = ts.parenthesizePrefixOperand(operand);
+        return node;
+    }
+    ts.createPrefix = createPrefix;
+    function updatePrefix(node, operand) {
+        return node.operand !== operand
+            ? updateNode(createPrefix(node.operator, operand), node)
+            : node;
+    }
+    ts.updatePrefix = updatePrefix;
+    function createPostfix(operand, operator) {
+        var node = createSynthesizedNode(199 /* PostfixUnaryExpression */);
+        node.operand = ts.parenthesizePostfixOperand(operand);
+        node.operator = operator;
+        return node;
+    }
+    ts.createPostfix = createPostfix;
+    function updatePostfix(node, operand) {
+        return node.operand !== operand
+            ? updateNode(createPostfix(operand, node.operator), node)
+            : node;
+    }
+    ts.updatePostfix = updatePostfix;
+    function createBinary(left, operator, right) {
+        var node = createSynthesizedNode(200 /* BinaryExpression */);
+        var operatorToken = asToken(operator);
+        var operatorKind = operatorToken.kind;
+        node.left = ts.parenthesizeBinaryOperand(operatorKind, left, /*isLeftSideOfBinary*/ true, /*leftOperand*/ undefined);
+        node.operatorToken = operatorToken;
+        node.right = ts.parenthesizeBinaryOperand(operatorKind, right, /*isLeftSideOfBinary*/ false, node.left);
+        return node;
+    }
+    ts.createBinary = createBinary;
+    function updateBinary(node, left, right, operator) {
+        return node.left !== left
+            || node.right !== right
+            ? updateNode(createBinary(left, operator || node.operatorToken, right), node)
+            : node;
+    }
+    ts.updateBinary = updateBinary;
+    function createConditional(condition, questionTokenOrWhenTrue, whenTrueOrWhenFalse, colonToken, whenFalse) {
+        var node = createSynthesizedNode(201 /* ConditionalExpression */);
+        node.condition = ts.parenthesizeForConditionalHead(condition);
+        node.questionToken = whenFalse ? questionTokenOrWhenTrue : createToken(55 /* QuestionToken */);
+        node.whenTrue = ts.parenthesizeSubexpressionOfConditionalExpression(whenFalse ? whenTrueOrWhenFalse : questionTokenOrWhenTrue);
+        node.colonToken = whenFalse ? colonToken : createToken(56 /* ColonToken */);
+        node.whenFalse = ts.parenthesizeSubexpressionOfConditionalExpression(whenFalse ? whenFalse : whenTrueOrWhenFalse);
+        return node;
+    }
+    ts.createConditional = createConditional;
+    function updateConditional(node, condition) {
+        var args = [];
+        for (var _i = 2; _i < arguments.length; _i++) {
+            args[_i - 2] = arguments[_i];
+        }
+        if (args.length === 2) {
+            var whenTrue_1 = args[0], whenFalse_1 = args[1];
+            return updateConditional(node, condition, node.questionToken, whenTrue_1, node.colonToken, whenFalse_1);
+        }
+        ts.Debug.assert(args.length === 4);
+        var questionToken = args[0], whenTrue = args[1], colonToken = args[2], whenFalse = args[3];
+        return node.condition !== condition
+            || node.questionToken !== questionToken
+            || node.whenTrue !== whenTrue
+            || node.colonToken !== colonToken
+            || node.whenFalse !== whenFalse
+            ? updateNode(createConditional(condition, questionToken, whenTrue, colonToken, whenFalse), node)
+            : node;
+    }
+    ts.updateConditional = updateConditional;
+    function createTemplateExpression(head, templateSpans) {
+        var node = createSynthesizedNode(202 /* TemplateExpression */);
+        node.head = head;
+        node.templateSpans = createNodeArray(templateSpans);
+        return node;
+    }
+    ts.createTemplateExpression = createTemplateExpression;
+    function updateTemplateExpression(node, head, templateSpans) {
+        return node.head !== head
+            || node.templateSpans !== templateSpans
+            ? updateNode(createTemplateExpression(head, templateSpans), node)
+            : node;
+    }
+    ts.updateTemplateExpression = updateTemplateExpression;
+    function createTemplateHead(text) {
+        var node = createSynthesizedNode(14 /* TemplateHead */);
+        node.text = text;
+        return node;
+    }
+    ts.createTemplateHead = createTemplateHead;
+    function createTemplateMiddle(text) {
+        var node = createSynthesizedNode(15 /* TemplateMiddle */);
+        node.text = text;
+        return node;
+    }
+    ts.createTemplateMiddle = createTemplateMiddle;
+    function createTemplateTail(text) {
+        var node = createSynthesizedNode(16 /* TemplateTail */);
+        node.text = text;
+        return node;
+    }
+    ts.createTemplateTail = createTemplateTail;
+    function createNoSubstitutionTemplateLiteral(text) {
+        var node = createSynthesizedNode(13 /* NoSubstitutionTemplateLiteral */);
+        node.text = text;
+        return node;
+    }
+    ts.createNoSubstitutionTemplateLiteral = createNoSubstitutionTemplateLiteral;
+    function createYield(asteriskTokenOrExpression, expression) {
+        var node = createSynthesizedNode(203 /* YieldExpression */);
+        node.asteriskToken = asteriskTokenOrExpression && asteriskTokenOrExpression.kind === 39 /* AsteriskToken */ ? asteriskTokenOrExpression : undefined;
+        node.expression = asteriskTokenOrExpression && asteriskTokenOrExpression.kind !== 39 /* AsteriskToken */ ? asteriskTokenOrExpression : expression;
+        return node;
+    }
+    ts.createYield = createYield;
+    function updateYield(node, asteriskToken, expression) {
+        return node.expression !== expression
+            || node.asteriskToken !== asteriskToken
+            ? updateNode(createYield(asteriskToken, expression), node)
+            : node;
+    }
+    ts.updateYield = updateYield;
+    function createSpread(expression) {
+        var node = createSynthesizedNode(204 /* SpreadElement */);
+        node.expression = ts.parenthesizeExpressionForList(expression);
+        return node;
+    }
+    ts.createSpread = createSpread;
+    function updateSpread(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createSpread(expression), node)
+            : node;
+    }
+    ts.updateSpread = updateSpread;
+    function createClassExpression(modifiers, name, typeParameters, heritageClauses, members) {
+        var node = createSynthesizedNode(205 /* ClassExpression */);
+        node.decorators = undefined;
+        node.modifiers = asNodeArray(modifiers);
+        node.name = asName(name);
+        node.typeParameters = asNodeArray(typeParameters);
+        node.heritageClauses = asNodeArray(heritageClauses);
+        node.members = createNodeArray(members);
+        return node;
+    }
+    ts.createClassExpression = createClassExpression;
+    function updateClassExpression(node, modifiers, name, typeParameters, heritageClauses, members) {
+        return node.modifiers !== modifiers
+            || node.name !== name
+            || node.typeParameters !== typeParameters
+            || node.heritageClauses !== heritageClauses
+            || node.members !== members
+            ? updateNode(createClassExpression(modifiers, name, typeParameters, heritageClauses, members), node)
+            : node;
+    }
+    ts.updateClassExpression = updateClassExpression;
+    function createOmittedExpression() {
+        return createSynthesizedNode(206 /* OmittedExpression */);
+    }
+    ts.createOmittedExpression = createOmittedExpression;
+    function createExpressionWithTypeArguments(typeArguments, expression) {
+        var node = createSynthesizedNode(207 /* ExpressionWithTypeArguments */);
+        node.expression = ts.parenthesizeForAccess(expression);
+        node.typeArguments = asNodeArray(typeArguments);
+        return node;
+    }
+    ts.createExpressionWithTypeArguments = createExpressionWithTypeArguments;
+    function updateExpressionWithTypeArguments(node, typeArguments, expression) {
+        return node.typeArguments !== typeArguments
+            || node.expression !== expression
+            ? updateNode(createExpressionWithTypeArguments(typeArguments, expression), node)
+            : node;
+    }
+    ts.updateExpressionWithTypeArguments = updateExpressionWithTypeArguments;
+    function createAsExpression(expression, type) {
+        var node = createSynthesizedNode(208 /* AsExpression */);
+        node.expression = expression;
+        node.type = type;
+        return node;
+    }
+    ts.createAsExpression = createAsExpression;
+    function updateAsExpression(node, expression, type) {
+        return node.expression !== expression
+            || node.type !== type
+            ? updateNode(createAsExpression(expression, type), node)
+            : node;
+    }
+    ts.updateAsExpression = updateAsExpression;
+    function createNonNullExpression(expression) {
+        var node = createSynthesizedNode(209 /* NonNullExpression */);
+        node.expression = ts.parenthesizeForAccess(expression);
+        return node;
+    }
+    ts.createNonNullExpression = createNonNullExpression;
+    function updateNonNullExpression(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createNonNullExpression(expression), node)
+            : node;
+    }
+    ts.updateNonNullExpression = updateNonNullExpression;
+    function createMetaProperty(keywordToken, name) {
+        var node = createSynthesizedNode(210 /* MetaProperty */);
+        node.keywordToken = keywordToken;
+        node.name = name;
+        return node;
+    }
+    ts.createMetaProperty = createMetaProperty;
+    function updateMetaProperty(node, name) {
+        return node.name !== name
+            ? updateNode(createMetaProperty(node.keywordToken, name), node)
+            : node;
+    }
+    ts.updateMetaProperty = updateMetaProperty;
+    // Misc
+    function createTemplateSpan(expression, literal) {
+        var node = createSynthesizedNode(211 /* TemplateSpan */);
+        node.expression = expression;
+        node.literal = literal;
+        return node;
+    }
+    ts.createTemplateSpan = createTemplateSpan;
+    function updateTemplateSpan(node, expression, literal) {
+        return node.expression !== expression
+            || node.literal !== literal
+            ? updateNode(createTemplateSpan(expression, literal), node)
+            : node;
+    }
+    ts.updateTemplateSpan = updateTemplateSpan;
+    function createSemicolonClassElement() {
+        return createSynthesizedNode(212 /* SemicolonClassElement */);
+    }
+    ts.createSemicolonClassElement = createSemicolonClassElement;
+    // Element
+    function createBlock(statements, multiLine) {
+        var block = createSynthesizedNode(213 /* Block */);
+        block.statements = createNodeArray(statements);
+        if (multiLine)
+            block.multiLine = multiLine;
+        return block;
+    }
+    ts.createBlock = createBlock;
+    /* @internal */
+    function createExpressionStatement(expression) {
+        var node = createSynthesizedNode(216 /* ExpressionStatement */);
+        node.expression = expression;
+        return node;
+    }
+    ts.createExpressionStatement = createExpressionStatement;
+    function updateBlock(node, statements) {
+        return node.statements !== statements
+            ? updateNode(createBlock(statements, node.multiLine), node)
+            : node;
+    }
+    ts.updateBlock = updateBlock;
+    function createVariableStatement(modifiers, declarationList) {
+        var node = createSynthesizedNode(214 /* VariableStatement */);
+        node.decorators = undefined;
+        node.modifiers = asNodeArray(modifiers);
+        node.declarationList = ts.isArray(declarationList) ? createVariableDeclarationList(declarationList) : declarationList;
+        return node;
+    }
+    ts.createVariableStatement = createVariableStatement;
+    function updateVariableStatement(node, modifiers, declarationList) {
+        return node.modifiers !== modifiers
+            || node.declarationList !== declarationList
+            ? updateNode(createVariableStatement(modifiers, declarationList), node)
+            : node;
+    }
+    ts.updateVariableStatement = updateVariableStatement;
+    function createEmptyStatement() {
+        return createSynthesizedNode(215 /* EmptyStatement */);
+    }
+    ts.createEmptyStatement = createEmptyStatement;
+    function createStatement(expression) {
+        return createExpressionStatement(ts.parenthesizeExpressionForExpressionStatement(expression));
+    }
+    ts.createStatement = createStatement;
+    function updateStatement(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createStatement(expression), node)
+            : node;
+    }
+    ts.updateStatement = updateStatement;
+    function createIf(expression, thenStatement, elseStatement) {
+        var node = createSynthesizedNode(217 /* IfStatement */);
+        node.expression = expression;
+        node.thenStatement = thenStatement;
+        node.elseStatement = elseStatement;
+        return node;
+    }
+    ts.createIf = createIf;
+    function updateIf(node, expression, thenStatement, elseStatement) {
+        return node.expression !== expression
+            || node.thenStatement !== thenStatement
+            || node.elseStatement !== elseStatement
+            ? updateNode(createIf(expression, thenStatement, elseStatement), node)
+            : node;
+    }
+    ts.updateIf = updateIf;
+    function createDo(statement, expression) {
+        var node = createSynthesizedNode(218 /* DoStatement */);
+        node.statement = statement;
+        node.expression = expression;
+        return node;
+    }
+    ts.createDo = createDo;
+    function updateDo(node, statement, expression) {
+        return node.statement !== statement
+            || node.expression !== expression
+            ? updateNode(createDo(statement, expression), node)
+            : node;
+    }
+    ts.updateDo = updateDo;
+    function createWhile(expression, statement) {
+        var node = createSynthesizedNode(219 /* WhileStatement */);
+        node.expression = expression;
+        node.statement = statement;
+        return node;
+    }
+    ts.createWhile = createWhile;
+    function updateWhile(node, expression, statement) {
+        return node.expression !== expression
+            || node.statement !== statement
+            ? updateNode(createWhile(expression, statement), node)
+            : node;
+    }
+    ts.updateWhile = updateWhile;
+    function createFor(initializer, condition, incrementor, statement) {
+        var node = createSynthesizedNode(220 /* ForStatement */);
+        node.initializer = initializer;
+        node.condition = condition;
+        node.incrementor = incrementor;
+        node.statement = statement;
+        return node;
+    }
+    ts.createFor = createFor;
+    function updateFor(node, initializer, condition, incrementor, statement) {
+        return node.initializer !== initializer
+            || node.condition !== condition
+            || node.incrementor !== incrementor
+            || node.statement !== statement
+            ? updateNode(createFor(initializer, condition, incrementor, statement), node)
+            : node;
+    }
+    ts.updateFor = updateFor;
+    function createForIn(initializer, expression, statement) {
+        var node = createSynthesizedNode(221 /* ForInStatement */);
+        node.initializer = initializer;
+        node.expression = expression;
+        node.statement = statement;
+        return node;
+    }
+    ts.createForIn = createForIn;
+    function updateForIn(node, initializer, expression, statement) {
+        return node.initializer !== initializer
+            || node.expression !== expression
+            || node.statement !== statement
+            ? updateNode(createForIn(initializer, expression, statement), node)
+            : node;
+    }
+    ts.updateForIn = updateForIn;
+    function createForOf(awaitModifier, initializer, expression, statement) {
+        var node = createSynthesizedNode(222 /* ForOfStatement */);
+        node.awaitModifier = awaitModifier;
+        node.initializer = initializer;
+        node.expression = expression;
+        node.statement = statement;
+        return node;
+    }
+    ts.createForOf = createForOf;
+    function updateForOf(node, awaitModifier, initializer, expression, statement) {
+        return node.awaitModifier !== awaitModifier
+            || node.initializer !== initializer
+            || node.expression !== expression
+            || node.statement !== statement
+            ? updateNode(createForOf(awaitModifier, initializer, expression, statement), node)
+            : node;
+    }
+    ts.updateForOf = updateForOf;
+    function createContinue(label) {
+        var node = createSynthesizedNode(223 /* ContinueStatement */);
+        node.label = asName(label);
+        return node;
+    }
+    ts.createContinue = createContinue;
+    function updateContinue(node, label) {
+        return node.label !== label
+            ? updateNode(createContinue(label), node)
+            : node;
+    }
+    ts.updateContinue = updateContinue;
+    function createBreak(label) {
+        var node = createSynthesizedNode(224 /* BreakStatement */);
+        node.label = asName(label);
+        return node;
+    }
+    ts.createBreak = createBreak;
+    function updateBreak(node, label) {
+        return node.label !== label
+            ? updateNode(createBreak(label), node)
+            : node;
+    }
+    ts.updateBreak = updateBreak;
+    function createReturn(expression) {
+        var node = createSynthesizedNode(225 /* ReturnStatement */);
+        node.expression = expression;
+        return node;
+    }
+    ts.createReturn = createReturn;
+    function updateReturn(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createReturn(expression), node)
+            : node;
+    }
+    ts.updateReturn = updateReturn;
+    function createWith(expression, statement) {
+        var node = createSynthesizedNode(226 /* WithStatement */);
+        node.expression = expression;
+        node.statement = statement;
+        return node;
+    }
+    ts.createWith = createWith;
+    function updateWith(node, expression, statement) {
+        return node.expression !== expression
+            || node.statement !== statement
+            ? updateNode(createWith(expression, statement), node)
+            : node;
+    }
+    ts.updateWith = updateWith;
+    function createSwitch(expression, caseBlock) {
+        var node = createSynthesizedNode(227 /* SwitchStatement */);
+        node.expression = ts.parenthesizeExpressionForList(expression);
+        node.caseBlock = caseBlock;
+        return node;
+    }
+    ts.createSwitch = createSwitch;
+    function updateSwitch(node, expression, caseBlock) {
+        return node.expression !== expression
+            || node.caseBlock !== caseBlock
+            ? updateNode(createSwitch(expression, caseBlock), node)
+            : node;
+    }
+    ts.updateSwitch = updateSwitch;
+    function createLabel(label, statement) {
+        var node = createSynthesizedNode(228 /* LabeledStatement */);
+        node.label = asName(label);
+        node.statement = statement;
+        return node;
+    }
+    ts.createLabel = createLabel;
+    function updateLabel(node, label, statement) {
+        return node.label !== label
+            || node.statement !== statement
+            ? updateNode(createLabel(label, statement), node)
+            : node;
+    }
+    ts.updateLabel = updateLabel;
+    function createThrow(expression) {
+        var node = createSynthesizedNode(229 /* ThrowStatement */);
+        node.expression = expression;
+        return node;
+    }
+    ts.createThrow = createThrow;
+    function updateThrow(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createThrow(expression), node)
+            : node;
+    }
+    ts.updateThrow = updateThrow;
+    function createTry(tryBlock, catchClause, finallyBlock) {
+        var node = createSynthesizedNode(230 /* TryStatement */);
+        node.tryBlock = tryBlock;
+        node.catchClause = catchClause;
+        node.finallyBlock = finallyBlock;
+        return node;
+    }
+    ts.createTry = createTry;
+    function updateTry(node, tryBlock, catchClause, finallyBlock) {
+        return node.tryBlock !== tryBlock
+            || node.catchClause !== catchClause
+            || node.finallyBlock !== finallyBlock
+            ? updateNode(createTry(tryBlock, catchClause, finallyBlock), node)
+            : node;
+    }
+    ts.updateTry = updateTry;
+    function createDebuggerStatement() {
+        return createSynthesizedNode(231 /* DebuggerStatement */);
+    }
+    ts.createDebuggerStatement = createDebuggerStatement;
+    function createVariableDeclaration(name, type, initializer) {
+        var node = createSynthesizedNode(232 /* VariableDeclaration */);
+        node.name = asName(name);
+        node.type = type;
+        node.initializer = initializer !== undefined ? ts.parenthesizeExpressionForList(initializer) : undefined;
+        return node;
+    }
+    ts.createVariableDeclaration = createVariableDeclaration;
+    function updateVariableDeclaration(node, name, type, initializer) {
+        return node.name !== name
+            || node.type !== type
+            || node.initializer !== initializer
+            ? updateNode(createVariableDeclaration(name, type, initializer), node)
+            : node;
+    }
+    ts.updateVariableDeclaration = updateVariableDeclaration;
+    function createVariableDeclarationList(declarations, flags) {
+        if (flags === void 0) { flags = 0 /* None */; }
+        var node = createSynthesizedNode(233 /* VariableDeclarationList */);
+        node.flags |= flags & 3 /* BlockScoped */;
+        node.declarations = createNodeArray(declarations);
+        return node;
+    }
+    ts.createVariableDeclarationList = createVariableDeclarationList;
+    function updateVariableDeclarationList(node, declarations) {
+        return node.declarations !== declarations
+            ? updateNode(createVariableDeclarationList(declarations, node.flags), node)
+            : node;
+    }
+    ts.updateVariableDeclarationList = updateVariableDeclarationList;
+    function createFunctionDeclaration(decorators, modifiers, asteriskToken, name, typeParameters, parameters, type, body) {
+        var node = createSynthesizedNode(234 /* FunctionDeclaration */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.asteriskToken = asteriskToken;
+        node.name = asName(name);
+        node.typeParameters = asNodeArray(typeParameters);
+        node.parameters = createNodeArray(parameters);
+        node.type = type;
+        node.body = body;
+        return node;
+    }
+    ts.createFunctionDeclaration = createFunctionDeclaration;
+    function updateFunctionDeclaration(node, decorators, modifiers, asteriskToken, name, typeParameters, parameters, type, body) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.asteriskToken !== asteriskToken
+            || node.name !== name
+            || node.typeParameters !== typeParameters
+            || node.parameters !== parameters
+            || node.type !== type
+            || node.body !== body
+            ? updateNode(createFunctionDeclaration(decorators, modifiers, asteriskToken, name, typeParameters, parameters, type, body), node)
+            : node;
+    }
+    ts.updateFunctionDeclaration = updateFunctionDeclaration;
+    function createClassDeclaration(decorators, modifiers, name, typeParameters, heritageClauses, members) {
+        var node = createSynthesizedNode(235 /* ClassDeclaration */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.name = asName(name);
+        node.typeParameters = asNodeArray(typeParameters);
+        node.heritageClauses = asNodeArray(heritageClauses);
+        node.members = createNodeArray(members);
+        return node;
+    }
+    ts.createClassDeclaration = createClassDeclaration;
+    function updateClassDeclaration(node, decorators, modifiers, name, typeParameters, heritageClauses, members) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.name !== name
+            || node.typeParameters !== typeParameters
+            || node.heritageClauses !== heritageClauses
+            || node.members !== members
+            ? updateNode(createClassDeclaration(decorators, modifiers, name, typeParameters, heritageClauses, members), node)
+            : node;
+    }
+    ts.updateClassDeclaration = updateClassDeclaration;
+    function createInterfaceDeclaration(decorators, modifiers, name, typeParameters, heritageClauses, members) {
+        var node = createSynthesizedNode(236 /* InterfaceDeclaration */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.name = asName(name);
+        node.typeParameters = asNodeArray(typeParameters);
+        node.heritageClauses = asNodeArray(heritageClauses);
+        node.members = createNodeArray(members);
+        return node;
+    }
+    ts.createInterfaceDeclaration = createInterfaceDeclaration;
+    function updateInterfaceDeclaration(node, decorators, modifiers, name, typeParameters, heritageClauses, members) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.name !== name
+            || node.typeParameters !== typeParameters
+            || node.heritageClauses !== heritageClauses
+            || node.members !== members
+            ? updateNode(createInterfaceDeclaration(decorators, modifiers, name, typeParameters, heritageClauses, members), node)
+            : node;
+    }
+    ts.updateInterfaceDeclaration = updateInterfaceDeclaration;
+    function createTypeAliasDeclaration(decorators, modifiers, name, typeParameters, type) {
+        var node = createSynthesizedNode(237 /* TypeAliasDeclaration */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.name = asName(name);
+        node.typeParameters = asNodeArray(typeParameters);
+        node.type = type;
+        return node;
+    }
+    ts.createTypeAliasDeclaration = createTypeAliasDeclaration;
+    function updateTypeAliasDeclaration(node, decorators, modifiers, name, typeParameters, type) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.name !== name
+            || node.typeParameters !== typeParameters
+            || node.type !== type
+            ? updateNode(createTypeAliasDeclaration(decorators, modifiers, name, typeParameters, type), node)
+            : node;
+    }
+    ts.updateTypeAliasDeclaration = updateTypeAliasDeclaration;
+    function createEnumDeclaration(decorators, modifiers, name, members) {
+        var node = createSynthesizedNode(238 /* EnumDeclaration */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.name = asName(name);
+        node.members = createNodeArray(members);
+        return node;
+    }
+    ts.createEnumDeclaration = createEnumDeclaration;
+    function updateEnumDeclaration(node, decorators, modifiers, name, members) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.name !== name
+            || node.members !== members
+            ? updateNode(createEnumDeclaration(decorators, modifiers, name, members), node)
+            : node;
+    }
+    ts.updateEnumDeclaration = updateEnumDeclaration;
+    function createModuleDeclaration(decorators, modifiers, name, body, flags) {
+        if (flags === void 0) { flags = 0 /* None */; }
+        var node = createSynthesizedNode(239 /* ModuleDeclaration */);
+        node.flags |= flags & (16 /* Namespace */ | 4 /* NestedNamespace */ | 512 /* GlobalAugmentation */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.name = name;
+        node.body = body;
+        return node;
+    }
+    ts.createModuleDeclaration = createModuleDeclaration;
+    function updateModuleDeclaration(node, decorators, modifiers, name, body) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.name !== name
+            || node.body !== body
+            ? updateNode(createModuleDeclaration(decorators, modifiers, name, body, node.flags), node)
+            : node;
+    }
+    ts.updateModuleDeclaration = updateModuleDeclaration;
+    function createModuleBlock(statements) {
+        var node = createSynthesizedNode(240 /* ModuleBlock */);
+        node.statements = createNodeArray(statements);
+        return node;
+    }
+    ts.createModuleBlock = createModuleBlock;
+    function updateModuleBlock(node, statements) {
+        return node.statements !== statements
+            ? updateNode(createModuleBlock(statements), node)
+            : node;
+    }
+    ts.updateModuleBlock = updateModuleBlock;
+    function createCaseBlock(clauses) {
+        var node = createSynthesizedNode(241 /* CaseBlock */);
+        node.clauses = createNodeArray(clauses);
+        return node;
+    }
+    ts.createCaseBlock = createCaseBlock;
+    function updateCaseBlock(node, clauses) {
+        return node.clauses !== clauses
+            ? updateNode(createCaseBlock(clauses), node)
+            : node;
+    }
+    ts.updateCaseBlock = updateCaseBlock;
+    function createNamespaceExportDeclaration(name) {
+        var node = createSynthesizedNode(242 /* NamespaceExportDeclaration */);
+        node.name = asName(name);
+        return node;
+    }
+    ts.createNamespaceExportDeclaration = createNamespaceExportDeclaration;
+    function updateNamespaceExportDeclaration(node, name) {
+        return node.name !== name
+            ? updateNode(createNamespaceExportDeclaration(name), node)
+            : node;
+    }
+    ts.updateNamespaceExportDeclaration = updateNamespaceExportDeclaration;
+    function createImportEqualsDeclaration(decorators, modifiers, name, moduleReference) {
+        var node = createSynthesizedNode(243 /* ImportEqualsDeclaration */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.name = asName(name);
+        node.moduleReference = moduleReference;
+        return node;
+    }
+    ts.createImportEqualsDeclaration = createImportEqualsDeclaration;
+    function updateImportEqualsDeclaration(node, decorators, modifiers, name, moduleReference) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.name !== name
+            || node.moduleReference !== moduleReference
+            ? updateNode(createImportEqualsDeclaration(decorators, modifiers, name, moduleReference), node)
+            : node;
+    }
+    ts.updateImportEqualsDeclaration = updateImportEqualsDeclaration;
+    function createImportDeclaration(decorators, modifiers, importClause, moduleSpecifier) {
+        var node = createSynthesizedNode(244 /* ImportDeclaration */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.importClause = importClause;
+        node.moduleSpecifier = moduleSpecifier;
+        return node;
+    }
+    ts.createImportDeclaration = createImportDeclaration;
+    function updateImportDeclaration(node, decorators, modifiers, importClause, moduleSpecifier) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.importClause !== importClause
+            || node.moduleSpecifier !== moduleSpecifier
+            ? updateNode(createImportDeclaration(decorators, modifiers, importClause, moduleSpecifier), node)
+            : node;
+    }
+    ts.updateImportDeclaration = updateImportDeclaration;
+    function createImportClause(name, namedBindings) {
+        var node = createSynthesizedNode(245 /* ImportClause */);
+        node.name = name;
+        node.namedBindings = namedBindings;
+        return node;
+    }
+    ts.createImportClause = createImportClause;
+    function updateImportClause(node, name, namedBindings) {
+        return node.name !== name
+            || node.namedBindings !== namedBindings
+            ? updateNode(createImportClause(name, namedBindings), node)
+            : node;
+    }
+    ts.updateImportClause = updateImportClause;
+    function createNamespaceImport(name) {
+        var node = createSynthesizedNode(246 /* NamespaceImport */);
+        node.name = name;
+        return node;
+    }
+    ts.createNamespaceImport = createNamespaceImport;
+    function updateNamespaceImport(node, name) {
+        return node.name !== name
+            ? updateNode(createNamespaceImport(name), node)
+            : node;
+    }
+    ts.updateNamespaceImport = updateNamespaceImport;
+    function createNamedImports(elements) {
+        var node = createSynthesizedNode(247 /* NamedImports */);
+        node.elements = createNodeArray(elements);
+        return node;
+    }
+    ts.createNamedImports = createNamedImports;
+    function updateNamedImports(node, elements) {
+        return node.elements !== elements
+            ? updateNode(createNamedImports(elements), node)
+            : node;
+    }
+    ts.updateNamedImports = updateNamedImports;
+    function createImportSpecifier(propertyName, name) {
+        var node = createSynthesizedNode(248 /* ImportSpecifier */);
+        node.propertyName = propertyName;
+        node.name = name;
+        return node;
+    }
+    ts.createImportSpecifier = createImportSpecifier;
+    function updateImportSpecifier(node, propertyName, name) {
+        return node.propertyName !== propertyName
+            || node.name !== name
+            ? updateNode(createImportSpecifier(propertyName, name), node)
+            : node;
+    }
+    ts.updateImportSpecifier = updateImportSpecifier;
+    function createExportAssignment(decorators, modifiers, isExportEquals, expression) {
+        var node = createSynthesizedNode(249 /* ExportAssignment */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.isExportEquals = isExportEquals;
+        node.expression = isExportEquals ? ts.parenthesizeBinaryOperand(58 /* EqualsToken */, expression, /*isLeftSideOfBinary*/ false, /*leftOperand*/ undefined) : ts.parenthesizeDefaultExpression(expression);
+        return node;
+    }
+    ts.createExportAssignment = createExportAssignment;
+    function updateExportAssignment(node, decorators, modifiers, expression) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.expression !== expression
+            ? updateNode(createExportAssignment(decorators, modifiers, node.isExportEquals, expression), node)
+            : node;
+    }
+    ts.updateExportAssignment = updateExportAssignment;
+    function createExportDeclaration(decorators, modifiers, exportClause, moduleSpecifier) {
+        var node = createSynthesizedNode(250 /* ExportDeclaration */);
+        node.decorators = asNodeArray(decorators);
+        node.modifiers = asNodeArray(modifiers);
+        node.exportClause = exportClause;
+        node.moduleSpecifier = moduleSpecifier;
+        return node;
+    }
+    ts.createExportDeclaration = createExportDeclaration;
+    function updateExportDeclaration(node, decorators, modifiers, exportClause, moduleSpecifier) {
+        return node.decorators !== decorators
+            || node.modifiers !== modifiers
+            || node.exportClause !== exportClause
+            || node.moduleSpecifier !== moduleSpecifier
+            ? updateNode(createExportDeclaration(decorators, modifiers, exportClause, moduleSpecifier), node)
+            : node;
+    }
+    ts.updateExportDeclaration = updateExportDeclaration;
+    function createNamedExports(elements) {
+        var node = createSynthesizedNode(251 /* NamedExports */);
+        node.elements = createNodeArray(elements);
+        return node;
+    }
+    ts.createNamedExports = createNamedExports;
+    function updateNamedExports(node, elements) {
+        return node.elements !== elements
+            ? updateNode(createNamedExports(elements), node)
+            : node;
+    }
+    ts.updateNamedExports = updateNamedExports;
+    function createExportSpecifier(propertyName, name) {
+        var node = createSynthesizedNode(252 /* ExportSpecifier */);
+        node.propertyName = asName(propertyName);
+        node.name = asName(name);
+        return node;
+    }
+    ts.createExportSpecifier = createExportSpecifier;
+    function updateExportSpecifier(node, propertyName, name) {
+        return node.propertyName !== propertyName
+            || node.name !== name
+            ? updateNode(createExportSpecifier(propertyName, name), node)
+            : node;
+    }
+    ts.updateExportSpecifier = updateExportSpecifier;
+    // Module references
+    function createExternalModuleReference(expression) {
+        var node = createSynthesizedNode(254 /* ExternalModuleReference */);
+        node.expression = expression;
+        return node;
+    }
+    ts.createExternalModuleReference = createExternalModuleReference;
+    function updateExternalModuleReference(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createExternalModuleReference(expression), node)
+            : node;
+    }
+    ts.updateExternalModuleReference = updateExternalModuleReference;
+    // JSX
+    function createJsxElement(openingElement, children, closingElement) {
+        var node = createSynthesizedNode(255 /* JsxElement */);
+        node.openingElement = openingElement;
+        node.children = createNodeArray(children);
+        node.closingElement = closingElement;
+        return node;
+    }
+    ts.createJsxElement = createJsxElement;
+    function updateJsxElement(node, openingElement, children, closingElement) {
+        return node.openingElement !== openingElement
+            || node.children !== children
+            || node.closingElement !== closingElement
+            ? updateNode(createJsxElement(openingElement, children, closingElement), node)
+            : node;
+    }
+    ts.updateJsxElement = updateJsxElement;
+    function createJsxSelfClosingElement(tagName, typeArguments, attributes) {
+        var node = createSynthesizedNode(256 /* JsxSelfClosingElement */);
+        node.tagName = tagName;
+        node.typeArguments = typeArguments && createNodeArray(typeArguments);
+        node.attributes = attributes;
+        return node;
+    }
+    ts.createJsxSelfClosingElement = createJsxSelfClosingElement;
+    function updateJsxSelfClosingElement(node, tagName, typeArguments, attributes) {
+        return node.tagName !== tagName
+            || node.typeArguments !== typeArguments
+            || node.attributes !== attributes
+            ? updateNode(createJsxSelfClosingElement(tagName, typeArguments, attributes), node)
+            : node;
+    }
+    ts.updateJsxSelfClosingElement = updateJsxSelfClosingElement;
+    function createJsxOpeningElement(tagName, typeArguments, attributes) {
+        var node = createSynthesizedNode(257 /* JsxOpeningElement */);
+        node.tagName = tagName;
+        node.typeArguments = typeArguments && createNodeArray(typeArguments);
+        node.attributes = attributes;
+        return node;
+    }
+    ts.createJsxOpeningElement = createJsxOpeningElement;
+    function updateJsxOpeningElement(node, tagName, typeArguments, attributes) {
+        return node.tagName !== tagName
+            || node.typeArguments !== typeArguments
+            || node.attributes !== attributes
+            ? updateNode(createJsxOpeningElement(tagName, typeArguments, attributes), node)
+            : node;
+    }
+    ts.updateJsxOpeningElement = updateJsxOpeningElement;
+    function createJsxClosingElement(tagName) {
+        var node = createSynthesizedNode(258 /* JsxClosingElement */);
+        node.tagName = tagName;
+        return node;
+    }
+    ts.createJsxClosingElement = createJsxClosingElement;
+    function updateJsxClosingElement(node, tagName) {
+        return node.tagName !== tagName
+            ? updateNode(createJsxClosingElement(tagName), node)
+            : node;
+    }
+    ts.updateJsxClosingElement = updateJsxClosingElement;
+    function createJsxFragment(openingFragment, children, closingFragment) {
+        var node = createSynthesizedNode(259 /* JsxFragment */);
+        node.openingFragment = openingFragment;
+        node.children = createNodeArray(children);
+        node.closingFragment = closingFragment;
+        return node;
+    }
+    ts.createJsxFragment = createJsxFragment;
+    function updateJsxFragment(node, openingFragment, children, closingFragment) {
+        return node.openingFragment !== openingFragment
+            || node.children !== children
+            || node.closingFragment !== closingFragment
+            ? updateNode(createJsxFragment(openingFragment, children, closingFragment), node)
+            : node;
+    }
+    ts.updateJsxFragment = updateJsxFragment;
+    function createJsxAttribute(name, initializer) {
+        var node = createSynthesizedNode(262 /* JsxAttribute */);
+        node.name = name;
+        node.initializer = initializer;
+        return node;
+    }
+    ts.createJsxAttribute = createJsxAttribute;
+    function updateJsxAttribute(node, name, initializer) {
+        return node.name !== name
+            || node.initializer !== initializer
+            ? updateNode(createJsxAttribute(name, initializer), node)
+            : node;
+    }
+    ts.updateJsxAttribute = updateJsxAttribute;
+    function createJsxAttributes(properties) {
+        var node = createSynthesizedNode(263 /* JsxAttributes */);
+        node.properties = createNodeArray(properties);
+        return node;
+    }
+    ts.createJsxAttributes = createJsxAttributes;
+    function updateJsxAttributes(node, properties) {
+        return node.properties !== properties
+            ? updateNode(createJsxAttributes(properties), node)
+            : node;
+    }
+    ts.updateJsxAttributes = updateJsxAttributes;
+    function createJsxSpreadAttribute(expression) {
+        var node = createSynthesizedNode(264 /* JsxSpreadAttribute */);
+        node.expression = expression;
+        return node;
+    }
+    ts.createJsxSpreadAttribute = createJsxSpreadAttribute;
+    function updateJsxSpreadAttribute(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createJsxSpreadAttribute(expression), node)
+            : node;
+    }
+    ts.updateJsxSpreadAttribute = updateJsxSpreadAttribute;
+    function createJsxExpression(dotDotDotToken, expression) {
+        var node = createSynthesizedNode(265 /* JsxExpression */);
+        node.dotDotDotToken = dotDotDotToken;
+        node.expression = expression;
+        return node;
+    }
+    ts.createJsxExpression = createJsxExpression;
+    function updateJsxExpression(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createJsxExpression(node.dotDotDotToken, expression), node)
+            : node;
+    }
+    ts.updateJsxExpression = updateJsxExpression;
+    // Clauses
+    function createCaseClause(expression, statements) {
+        var node = createSynthesizedNode(266 /* CaseClause */);
+        node.expression = ts.parenthesizeExpressionForList(expression);
+        node.statements = createNodeArray(statements);
+        return node;
+    }
+    ts.createCaseClause = createCaseClause;
+    function updateCaseClause(node, expression, statements) {
+        return node.expression !== expression
+            || node.statements !== statements
+            ? updateNode(createCaseClause(expression, statements), node)
+            : node;
+    }
+    ts.updateCaseClause = updateCaseClause;
+    function createDefaultClause(statements) {
+        var node = createSynthesizedNode(267 /* DefaultClause */);
+        node.statements = createNodeArray(statements);
+        return node;
+    }
+    ts.createDefaultClause = createDefaultClause;
+    function updateDefaultClause(node, statements) {
+        return node.statements !== statements
+            ? updateNode(createDefaultClause(statements), node)
+            : node;
+    }
+    ts.updateDefaultClause = updateDefaultClause;
+    function createHeritageClause(token, types) {
+        var node = createSynthesizedNode(268 /* HeritageClause */);
+        node.token = token;
+        node.types = createNodeArray(types);
+        return node;
+    }
+    ts.createHeritageClause = createHeritageClause;
+    function updateHeritageClause(node, types) {
+        return node.types !== types
+            ? updateNode(createHeritageClause(node.token, types), node)
+            : node;
+    }
+    ts.updateHeritageClause = updateHeritageClause;
+    function createCatchClause(variableDeclaration, block) {
+        var node = createSynthesizedNode(269 /* CatchClause */);
+        node.variableDeclaration = ts.isString(variableDeclaration) ? createVariableDeclaration(variableDeclaration) : variableDeclaration;
+        node.block = block;
+        return node;
+    }
+    ts.createCatchClause = createCatchClause;
+    function updateCatchClause(node, variableDeclaration, block) {
+        return node.variableDeclaration !== variableDeclaration
+            || node.block !== block
+            ? updateNode(createCatchClause(variableDeclaration, block), node)
+            : node;
+    }
+    ts.updateCatchClause = updateCatchClause;
+    // Property assignments
+    function createPropertyAssignment(name, initializer) {
+        var node = createSynthesizedNode(270 /* PropertyAssignment */);
+        node.name = asName(name);
+        node.questionToken = undefined;
+        node.initializer = ts.parenthesizeExpressionForList(initializer);
+        return node;
+    }
+    ts.createPropertyAssignment = createPropertyAssignment;
+    function updatePropertyAssignment(node, name, initializer) {
+        return node.name !== name
+            || node.initializer !== initializer
+            ? updateNode(createPropertyAssignment(name, initializer), node)
+            : node;
+    }
+    ts.updatePropertyAssignment = updatePropertyAssignment;
+    function createShorthandPropertyAssignment(name, objectAssignmentInitializer) {
+        var node = createSynthesizedNode(271 /* ShorthandPropertyAssignment */);
+        node.name = asName(name);
+        node.objectAssignmentInitializer = objectAssignmentInitializer !== undefined ? ts.parenthesizeExpressionForList(objectAssignmentInitializer) : undefined;
+        return node;
+    }
+    ts.createShorthandPropertyAssignment = createShorthandPropertyAssignment;
+    function updateShorthandPropertyAssignment(node, name, objectAssignmentInitializer) {
+        return node.name !== name
+            || node.objectAssignmentInitializer !== objectAssignmentInitializer
+            ? updateNode(createShorthandPropertyAssignment(name, objectAssignmentInitializer), node)
+            : node;
+    }
+    ts.updateShorthandPropertyAssignment = updateShorthandPropertyAssignment;
+    function createSpreadAssignment(expression) {
+        var node = createSynthesizedNode(272 /* SpreadAssignment */);
+        node.expression = expression !== undefined ? ts.parenthesizeExpressionForList(expression) : undefined; // TODO: GH#18217
+        return node;
+    }
+    ts.createSpreadAssignment = createSpreadAssignment;
+    function updateSpreadAssignment(node, expression) {
+        return node.expression !== expression
+            ? updateNode(createSpreadAssignment(expression), node)
+            : node;
+    }
+    ts.updateSpreadAssignment = updateSpreadAssignment;
+    // Enum
+    function createEnumMember(name, initializer) {
+        var node = createSynthesizedNode(273 /* EnumMember */);
+        node.name = asName(name);
+        node.initializer = initializer && ts.parenthesizeExpressionForList(initializer);
+        return node;
+    }
+    ts.createEnumMember = createEnumMember;
+    function updateEnumMember(node, name, initializer) {
+        return node.name !== name
+            || node.initializer !== initializer
+            ? updateNode(createEnumMember(name, initializer), node)
+            : node;
+    }
+    ts.updateEnumMember = updateEnumMember;
+    // Top-level nodes
+    function updateSourceFileNode(node, statements, isDeclarationFile, referencedFiles, typeReferences, hasNoDefaultLib, libReferences) {
+        if (node.statements !== statements ||
+            (isDeclarationFile !== undefined && node.isDeclarationFile !== isDeclarationFile) ||
+            (referencedFiles !== undefined && node.referencedFiles !== referencedFiles) ||
+            (typeReferences !== undefined && node.typeReferenceDirectives !== typeReferences) ||
+            (libReferences !== undefined && node.libReferenceDirectives !== libReferences) ||
+            (hasNoDefaultLib !== undefined && node.hasNoDefaultLib !== hasNoDefaultLib)) {
+            var updated = createSynthesizedNode(274 /* SourceFile */);
+            updated.flags |= node.flags;
+            updated.statements = createNodeArray(statements);
+            updated.endOfFileToken = node.endOfFileToken;
+            updated.fileName = node.fileName;
+            updated.path = node.path;
+            updated.text = node.text;
+            updated.isDeclarationFile = isDeclarationFile === undefined ? node.isDeclarationFile : isDeclarationFile;
+            updated.referencedFiles = referencedFiles === undefined ? node.referencedFiles : referencedFiles;
+            updated.typeReferenceDirectives = typeReferences === undefined ? node.typeReferenceDirectives : typeReferences;
+            updated.hasNoDefaultLib = hasNoDefaultLib === undefined ? node.hasNoDefaultLib : hasNoDefaultLib;
+            updated.libReferenceDirectives = libReferences === undefined ? node.libReferenceDirectives : libReferences;
+            if (node.amdDependencies !== undefined)
+                updated.amdDependencies = node.amdDependencies;
+            if (node.moduleName !== undefined)
+                updated.moduleName = node.moduleName;
+            if (node.languageVariant !== undefined)
+                updated.languageVariant = node.languageVariant;
+            if (node.renamedDependencies !== undefined)
+                updated.renamedDependencies = node.renamedDependencies;
+            if (node.languageVersion !== undefined)
+                updated.languageVersion = node.languageVersion;
+            if (node.scriptKind !== undefined)
+                updated.scriptKind = node.scriptKind;
+            if (node.externalModuleIndicator !== undefined)
+                updated.externalModuleIndicator = node.externalModuleIndicator;
+            if (node.commonJsModuleIndicator !== undefined)
+                updated.commonJsModuleIndicator = node.commonJsModuleIndicator;
+            if (node.identifiers !== undefined)
+                updated.identifiers = node.identifiers;
+            if (node.nodeCount !== undefined)
+                updated.nodeCount = node.nodeCount;
+            if (node.identifierCount !== undefined)
+                updated.identifierCount = node.identifierCount;
+            if (node.symbolCount !== undefined)
+                updated.symbolCount = node.symbolCount;
+            if (node.parseDiagnostics !== undefined)
+                updated.parseDiagnostics = node.parseDiagnostics;
+            if (node.bindDiagnostics !== undefined)
+                updated.bindDiagnostics = node.bindDiagnostics;
+            if (node.bindSuggestionDiagnostics !== undefined)
+                updated.bindSuggestionDiagnostics = node.bindSuggestionDiagnostics;
+            if (node.lineMap !== undefined)
+                updated.lineMap = node.lineMap;
+            if (node.classifiableNames !== undefined)
+                updated.classifiableNames = node.classifiableNames;
+            if (node.resolvedModules !== undefined)
+                updated.resolvedModules = node.resolvedModules;
+            if (node.resolvedTypeReferenceDirectiveNames !== undefined)
+                updated.resolvedTypeReferenceDirectiveNames = node.resolvedTypeReferenceDirectiveNames;
+            if (node.imports !== undefined)
+                updated.imports = node.imports;
+            if (node.moduleAugmentations !== undefined)
+                updated.moduleAugmentations = node.moduleAugmentations;
+            if (node.pragmas !== undefined)
+                updated.pragmas = node.pragmas;
+            if (node.localJsxFactory !== undefined)
+                updated.localJsxFactory = node.localJsxFactory;
+            if (node.localJsxNamespace !== undefined)
+                updated.localJsxNamespace = node.localJsxNamespace;
+            return updateNode(updated, node);
+        }
+        return node;
+    }
+    ts.updateSourceFileNode = updateSourceFileNode;
+    /**
+     * Creates a shallow, memberwise clone of a node for mutation.
+     */
+    function getMutableClone(node) {
+        var clone = getSynthesizedClone(node);
+        clone.pos = node.pos;
+        clone.end = node.end;
+        clone.parent = node.parent;
+        return clone;
+    }
+    ts.getMutableClone = getMutableClone;
+    // Transformation nodes
+    /**
+     * Creates a synthetic statement to act as a placeholder for a not-emitted statement in
+     * order to preserve comments.
+     *
+     * @param original The original statement.
+     */
+    function createNotEmittedStatement(original) {
+        var node = createSynthesizedNode(300 /* NotEmittedStatement */);
+        node.original = original;
+        setTextRange(node, original);
+        return node;
+    }
+    ts.createNotEmittedStatement = createNotEmittedStatement;
+    /**
+     * Creates a synthetic element to act as a placeholder for the end of an emitted declaration in
+     * order to properly emit exports.
+     */
+    /* @internal */
+    function createEndOfDeclarationMarker(original) {
+        var node = createSynthesizedNode(304 /* EndOfDeclarationMarker */);
+        node.emitNode = {};
+        node.original = original;
+        return node;
+    }
+    ts.createEndOfDeclarationMarker = createEndOfDeclarationMarker;
+    /**
+     * Creates a synthetic element to act as a placeholder for the beginning of a merged declaration in
+     * order to properly emit exports.
+     */
+    /* @internal */
+    function createMergeDeclarationMarker(original) {
+        var node = createSynthesizedNode(303 /* MergeDeclarationMarker */);
+        node.emitNode = {};
+        node.original = original;
+        return node;
+    }
+    ts.createMergeDeclarationMarker = createMergeDeclarationMarker;
+    /**
+     * Creates a synthetic expression to act as a placeholder for a not-emitted expression in
+     * order to preserve comments or sourcemap positions.
+     *
+     * @param expression The inner expression to emit.
+     * @param original The original outer expression.
+     * @param location The location for the expression. Defaults to the positions from "original" if provided.
+     */
+    function createPartiallyEmittedExpression(expression, original) {
+        var node = createSynthesizedNode(301 /* PartiallyEmittedExpression */);
+        node.expression = expression;
+        node.original = original;
+        setTextRange(node, original);
+        return node;
+    }
+    ts.createPartiallyEmittedExpression = createPartiallyEmittedExpression;
+    function updatePartiallyEmittedExpression(node, expression) {
+        if (node.expression !== expression) {
+            return updateNode(createPartiallyEmittedExpression(expression, node.original), node);
+        }
+        return node;
+    }
+    ts.updatePartiallyEmittedExpression = updatePartiallyEmittedExpression;
+    function flattenCommaElements(node) {
+        if (ts.nodeIsSynthesized(node) && !ts.isParseTreeNode(node) && !node.original && !node.emitNode && !node.id) {
+            if (node.kind === 302 /* CommaListExpression */) {
+                return node.elements;
+            }
+            if (ts.isBinaryExpression(node) && node.operatorToken.kind === 26 /* CommaToken */) {
+                return [node.left, node.right];
+            }
+        }
+        return node;
+    }
+    function createCommaList(elements) {
+        var node = createSynthesizedNode(302 /* CommaListExpression */);
+        node.elements = createNodeArray(ts.sameFlatMap(elements, flattenCommaElements));
+        return node;
+    }
+    ts.createCommaList = createCommaList;
+    function updateCommaList(node, elements) {
+        return node.elements !== elements
+            ? updateNode(createCommaList(elements), node)
+            : node;
+    }
+    ts.updateCommaList = updateCommaList;
+    function createBundle(sourceFiles, prepends) {
+        if (prepends === void 0) { prepends = ts.emptyArray; }
+        var node = ts.createNode(275 /* Bundle */);
+        node.prepends = prepends;
+        node.sourceFiles = sourceFiles;
+        return node;
+    }
+    ts.createBundle = createBundle;
+    function createUnparsedSourceFile(text, map) {
+        var node = ts.createNode(276 /* UnparsedSource */);
+        node.text = text;
+        node.sourceMapText = map;
+        return node;
+    }
+    ts.createUnparsedSourceFile = createUnparsedSourceFile;
+    function createInputFiles(javascript, declaration, javascriptMapText, declarationMapText) {
+        var node = ts.createNode(277 /* InputFiles */);
+        node.javascriptText = javascript;
+        node.javascriptMapText = javascriptMapText;
+        node.declarationText = declaration;
+        node.declarationMapText = declarationMapText;
+        return node;
+    }
+    ts.createInputFiles = createInputFiles;
+    function updateBundle(node, sourceFiles, prepends) {
+        if (prepends === void 0) { prepends = ts.emptyArray; }
+        if (node.sourceFiles !== sourceFiles || node.prepends !== prepends) {
+            return createBundle(sourceFiles, prepends);
+        }
+        return node;
+    }
+    ts.updateBundle = updateBundle;
+    function createImmediatelyInvokedFunctionExpression(statements, param, paramValue) {
+        return createCall(createFunctionExpression(
+        /*modifiers*/ undefined, 
+        /*asteriskToken*/ undefined, 
+        /*name*/ undefined, 
+        /*typeParameters*/ undefined, 
+        /*parameters*/ param ? [param] : [], 
+        /*type*/ undefined, createBlock(statements, /*multiLine*/ true)), 
+        /*typeArguments*/ undefined, 
+        /*argumentsArray*/ paramValue ? [paramValue] : []);
+    }
+    ts.createImmediatelyInvokedFunctionExpression = createImmediatelyInvokedFunctionExpression;
+    function createImmediatelyInvokedArrowFunction(statements, param, paramValue) {
+        return createCall(createArrowFunction(
+        /*modifiers*/ undefined, 
+        /*typeParameters*/ undefined, 
+        /*parameters*/ param ? [param] : [], 
+        /*type*/ undefined, 
+        /*equalsGreaterThanToken*/ undefined, createBlock(statements, /*multiLine*/ true)), 
+        /*typeArguments*/ undefined, 
+        /*argumentsArray*/ paramValue ? [paramValue] : []);
+    }
+    ts.createImmediatelyInvokedArrowFunction = createImmediatelyInvokedArrowFunction;
+    function createComma(left, right) {
+        return createBinary(left, 26 /* CommaToken */, right);
+    }
+    ts.createComma = createComma;
+    function createLessThan(left, right) {
+        return createBinary(left, 27 /* LessThanToken */, right);
+    }
+    ts.createLessThan = createLessThan;
+    function createAssignment(left, right) {
+        return createBinary(left, 58 /* EqualsToken */, right);
+    }
+    ts.createAssignment = createAssignment;
+    function createStrictEquality(left, right) {
+        return createBinary(left, 34 /* EqualsEqualsEqualsToken */, right);
+    }
+    ts.createStrictEquality = createStrictEquality;
+    function createStrictInequality(left, right) {
+        return createBinary(left, 35 /* ExclamationEqualsEqualsToken */, right);
+    }
+    ts.createStrictInequality = createStrictInequality;
+    function createAdd(left, right) {
+        return createBinary(left, 37 /* PlusToken */, right);
+    }
+    ts.createAdd = createAdd;
+    function createSubtract(left, right) {
+        return createBinary(left, 38 /* MinusToken */, right);
+    }
+    ts.createSubtract = createSubtract;
+    function createPostfixIncrement(operand) {
+        return createPostfix(operand, 43 /* PlusPlusToken */);
+    }
+    ts.createPostfixIncrement = createPostfixIncrement;
+    function createLogicalAnd(left, right) {
+        return createBinary(left, 53 /* AmpersandAmpersandToken */, right);
+    }
+    ts.createLogicalAnd = createLogicalAnd;
+    function createLogicalOr(left, right) {
+        return createBinary(left, 54 /* BarBarToken */, right);
+    }
+    ts.createLogicalOr = createLogicalOr;
+    function createLogicalNot(operand) {
+        return createPrefix(51 /* ExclamationToken */, operand);
+    }
+    ts.createLogicalNot = createLogicalNot;
+    function createVoidZero() {
+        return createVoid(createLiteral(0));
+    }
+    ts.createVoidZero = createVoidZero;
+    function createExportDefault(expression) {
+        return createExportAssignment(/*decorators*/ undefined, /*modifiers*/ undefined, /*isExportEquals*/ false, expression);
+    }
+    ts.createExportDefault = createExportDefault;
+    function createExternalModuleExport(exportName) {
+        return createExportDeclaration(/*decorators*/ undefined, /*modifiers*/ undefined, createNamedExports([createExportSpecifier(/*propertyName*/ undefined, exportName)]));
+    }
+    ts.createExternalModuleExport = createExternalModuleExport;
+    // Utilities
+    function asName(name) {
+        return ts.isString(name) ? createIdentifier(name) : name;
+    }
+    function asExpression(value) {
+        return ts.isString(value) || typeof value === "number" ? createLiteral(value) : value;
+    }
+    function asNodeArray(array) {
+        return array ? createNodeArray(array) : undefined;
+    }
+    function asToken(value) {
+        return typeof value === "number" ? createToken(value) : value;
+    }
+    /**
+     * Clears any EmitNode entries from parse-tree nodes.
+     * @param sourceFile A source file.
+     */
+    function disposeEmitNodes(sourceFile) {
+        // During transformation we may need to annotate a parse tree node with transient
+        // transformation properties. As parse tree nodes live longer than transformation
+        // nodes, we need to make sure we reclaim any memory allocated for custom ranges
+        // from these nodes to ensure we do not hold onto entire subtrees just for position
+        // information. We also need to reset these nodes to a pre-transformation state
+        // for incremental parsing scenarios so that we do not impact later emit.
+        sourceFile = ts.getSourceFileOfNode(ts.getParseTreeNode(sourceFile));
+        var emitNode = sourceFile && sourceFile.emitNode;
+        var annotatedNodes = emitNode && emitNode.annotatedNodes;
+        if (annotatedNodes) {
+            for (var _i = 0, annotatedNodes_1 = annotatedNodes; _i < annotatedNodes_1.length; _i++) {
+                var node = annotatedNodes_1[_i];
+                node.emitNode = undefined;
+            }
+        }
+    }
+    ts.disposeEmitNodes = disposeEmitNodes;
+    /**
+     * Associates a node with the current transformation, initializing
+     * various transient transformation properties.
+     */
+    /* @internal */
+    function getOrCreateEmitNode(node) {
+        if (!node.emitNode) {
+            if (ts.isParseTreeNode(node)) {
+                // To avoid holding onto transformation artifacts, we keep track of any
+                // parse tree node we are annotating. This allows us to clean them up after
+                // all transformations have completed.
+                if (node.kind === 274 /* SourceFile */) {
+                    return node.emitNode = { annotatedNodes: [node] };
+                }
+                var sourceFile = ts.getSourceFileOfNode(node);
+                getOrCreateEmitNode(sourceFile).annotatedNodes.push(node);
+            }
+            node.emitNode = {};
+        }
+        return node.emitNode;
+    }
+    ts.getOrCreateEmitNode = getOrCreateEmitNode;
+    function setTextRange(range, location) {
+        if (location) {
+            range.pos = location.pos;
+            range.end = location.end;
+        }
+        return range;
+    }
+    ts.setTextRange = setTextRange;
+    /**
+     * Sets flags that control emit behavior of a node.
+     */
+    function setEmitFlags(node, emitFlags) {
+        getOrCreateEmitNode(node).flags = emitFlags;
+        return node;
+    }
+    ts.setEmitFlags = setEmitFlags;
+    /**
+     * Sets flags that control emit behavior of a node.
+     */
+    /* @internal */
+    function addEmitFlags(node, emitFlags) {
+        var emitNode = getOrCreateEmitNode(node);
+        emitNode.flags = emitNode.flags | emitFlags;
+        return node;
+    }
+    ts.addEmitFlags = addEmitFlags;
+    /**
+     * Gets a custom text range to use when emitting source maps.
+     */
+    function getSourceMapRange(node) {
+        var emitNode = node.emitNode;
+        return (emitNode && emitNode.sourceMapRange) || node;
+    }
+    ts.getSourceMapRange = getSourceMapRange;
+    /**
+     * Sets a custom text range to use when emitting source maps.
+     */
+    function setSourceMapRange(node, range) {
+        getOrCreateEmitNode(node).sourceMapRange = range;
+        return node;
+    }
+    ts.setSourceMapRange = setSourceMapRange;
+    // tslint:disable-next-line variable-name
+    var SourceMapSource;
+    /**
+     * Create an external source map source file reference
+     */
+    function createSourceMapSource(fileName, text, skipTrivia) {
+        return new (SourceMapSource || (SourceMapSource = ts.objectAllocator.getSourceMapSourceConstructor()))(fileName, text, skipTrivia);
+    }
+    ts.createSourceMapSource = createSourceMapSource;
+    /**
+     * Gets the TextRange to use for source maps for a token of a node.
+     */
+    function getTokenSourceMapRange(node, token) {
+        var emitNode = node.emitNode;
+        var tokenSourceMapRanges = emitNode && emitNode.tokenSourceMapRanges;
+        return tokenSourceMapRanges && tokenSourceMapRanges[token];
+    }
+    ts.getTokenSourceMapRange = getTokenSourceMapRange;
+    /**
+     * Sets the TextRange to use for source maps for a token of a node.
+     */
+    function setTokenSourceMapRange(node, token, range) {
+        var emitNode = getOrCreateEmitNode(node);
+        var tokenSourceMapRanges = emitNode.tokenSourceMapRanges || (emitNode.tokenSourceMapRanges = []);
+        tokenSourceMapRanges[token] = range;
+        return node;
+    }
+    ts.setTokenSourceMapRange = setTokenSourceMapRange;
+    /**
+     * Gets a custom text range to use when emitting comments.
+     */
+    /*@internal*/
+    function getStartsOnNewLine(node) {
+        var emitNode = node.emitNode;
+        return emitNode && emitNode.startsOnNewLine;
+    }
+    ts.getStartsOnNewLine = getStartsOnNewLine;
+    /**
+     * Sets a custom text range to use when emitting comments.
+     */
+    /*@internal*/
+    function setStartsOnNewLine(node, newLine) {
+        getOrCreateEmitNode(node).startsOnNewLine = newLine;
+        return node;
+    }
+    ts.setStartsOnNewLine = setStartsOnNewLine;
+    /**
+     * Gets a custom text range to use when emitting comments.
+     */
+    function getCommentRange(node) {
+        var emitNode = node.emitNode;
+        return (emitNode && emitNode.commentRange) || node;
+    }
+    ts.getCommentRange = getCommentRange;
+    /**
+     * Sets a custom text range to use when emitting comments.
+     */
+    function setCommentRange(node, range) {
+        getOrCreateEmitNode(node).commentRange = range;
+        return node;
+    }
+    ts.setCommentRange = setCommentRange;
+    function getSyntheticLeadingComments(node) {
+        var emitNode = node.emitNode;
+        return emitNode && emitNode.leadingComments;
+    }
+    ts.getSyntheticLeadingComments = getSyntheticLeadingComments;
+    function setSyntheticLeadingComments(node, comments) {
+        getOrCreateEmitNode(node).leadingComments = comments;
+        return node;
+    }
+    ts.setSyntheticLeadingComments = setSyntheticLeadingComments;
+    function addSyntheticLeadingComment(node, kind, text, hasTrailingNewLine) {
+        return setSyntheticLeadingComments(node, ts.append(getSyntheticLeadingComments(node), { kind: kind, pos: -1, end: -1, hasTrailingNewLine: hasTrailingNewLine, text: text }));
+    }
+    ts.addSyntheticLeadingComment = addSyntheticLeadingComment;
+    function getSyntheticTrailingComments(node) {
+        var emitNode = node.emitNode;
+        return emitNode && emitNode.trailingComments;
+    }
+    ts.getSyntheticTrailingComments = getSyntheticTrailingComments;
+    function setSyntheticTrailingComments(node, comments) {
+        getOrCreateEmitNode(node).trailingComments = comments;
+        return node;
+    }
+    ts.setSyntheticTrailingComments = setSyntheticTrailingComments;
+    function addSyntheticTrailingComment(node, kind, text, hasTrailingNewLine) {
+        return setSyntheticTrailingComments(node, ts.append(getSyntheticTrailingComments(node), { kind: kind, pos: -1, end: -1, hasTrailingNewLine: hasTrailingNewLine, text: text }));
+    }
+    ts.addSyntheticTrailingComment = addSyntheticTrailingComment;
+    function moveSyntheticComments(node, original) {
+        setSyntheticLeadingComments(node, getSyntheticLeadingComments(original));
+        setSyntheticTrailingComments(node, getSyntheticTrailingComments(original));
+        var emit = getOrCreateEmitNode(original);
+        emit.leadingComments = undefined;
+        emit.trailingComments = undefined;
+        return node;
+    }
+    ts.moveSyntheticComments = moveSyntheticComments;
+    /**
+     * Gets the constant value to emit for an expression.
+     */
+    function getConstantValue(node) {
+        var emitNode = node.emitNode;
+        return emitNode && emitNode.constantValue;
+    }
+    ts.getConstantValue = getConstantValue;
+    /**
+     * Sets the constant value to emit for an expression.
+     */
+    function setConstantValue(node, value) {
+        var emitNode = getOrCreateEmitNode(node);
+        emitNode.constantValue = value;
+        return node;
+    }
+    ts.setConstantValue = setConstantValue;
+    /**
+     * Adds an EmitHelper to a node.
+     */
+    function addEmitHelper(node, helper) {
+        var emitNode = getOrCreateEmitNode(node);
+        emitNode.helpers = ts.append(emitNode.helpers, helper);
+        return node;
+    }
+    ts.addEmitHelper = addEmitHelper;
+    /**
+     * Add EmitHelpers to a node.
+     */
+    function addEmitHelpers(node, helpers) {
+        if (ts.some(helpers)) {
+            var emitNode = getOrCreateEmitNode(node);
+            for (var _i = 0, helpers_1 = helpers; _i < helpers_1.length; _i++) {
+                var helper = helpers_1[_i];
+                emitNode.helpers = ts.appendIfUnique(emitNode.helpers, helper);
+            }
+        }
+        return node;
+    }
+    ts.addEmitHelpers = addEmitHelpers;
+    /**
+     * Removes an EmitHelper from a node.
+     */
+    function removeEmitHelper(node, helper) {
+        var emitNode = node.emitNode;
+        if (emitNode) {
+            var helpers = emitNode.helpers;
+            if (helpers) {
+                return ts.orderedRemoveItem(helpers, helper);
+            }
+        }
+        return false;
+    }
+    ts.removeEmitHelper = removeEmitHelper;
+    /**
+     * Gets the EmitHelpers of a node.
+     */
+    function getEmitHelpers(node) {
+        var emitNode = node.emitNode;
+        return emitNode && emitNode.helpers;
+    }
+    ts.getEmitHelpers = getEmitHelpers;
+    /**
+     * Moves matching emit helpers from a source node to a target node.
+     */
+    function moveEmitHelpers(source, target, predicate) {
+        var sourceEmitNode = source.emitNode;
+        var sourceEmitHelpers = sourceEmitNode && sourceEmitNode.helpers;
+        if (!ts.some(sourceEmitHelpers))
+            return;
+        var targetEmitNode = getOrCreateEmitNode(target);
+        var helpersRemoved = 0;
+        for (var i = 0; i < sourceEmitHelpers.length; i++) {
+            var helper = sourceEmitHelpers[i];
+            if (predicate(helper)) {
+                helpersRemoved++;
+                targetEmitNode.helpers = ts.appendIfUnique(targetEmitNode.helpers, helper);
+            }
+            else if (helpersRemoved > 0) {
+                sourceEmitHelpers[i - helpersRemoved] = helper;
+            }
+        }
+        if (helpersRemoved > 0) {
+            sourceEmitHelpers.length -= helpersRemoved;
+        }
+    }
+    ts.moveEmitHelpers = moveEmitHelpers;
+    /* @internal */
+    function compareEmitHelpers(x, y) {
+        if (x === y)
+            return 0 /* EqualTo */;
+        if (x.priority === y.priority)
+            return 0 /* EqualTo */;
+        if (x.priority === undefined)
+            return 1 /* GreaterThan */;
+        if (y.priority === undefined)
+            return -1 /* LessThan */;
+        return ts.compareValues(x.priority, y.priority);
+    }
+    ts.compareEmitHelpers = compareEmitHelpers;
+    function setOriginalNode(node, original) {
+        node.original = original;
+        if (original) {
+            var emitNode = original.emitNode;
+            if (emitNode)
+                node.emitNode = mergeEmitNode(emitNode, node.emitNode);
+        }
+        return node;
+    }
+    ts.setOriginalNode = setOriginalNode;
+    function mergeEmitNode(sourceEmitNode, destEmitNode) {
+        var flags = sourceEmitNode.flags, leadingComments = sourceEmitNode.leadingComments, trailingComments = sourceEmitNode.trailingComments, commentRange = sourceEmitNode.commentRange, sourceMapRange = sourceEmitNode.sourceMapRange, tokenSourceMapRanges = sourceEmitNode.tokenSourceMapRanges, constantValue = sourceEmitNode.constantValue, helpers = sourceEmitNode.helpers, startsOnNewLine = sourceEmitNode.startsOnNewLine;
+        if (!destEmitNode)
+            destEmitNode = {};
+        // We are using `.slice()` here in case `destEmitNode.leadingComments` is pushed to later.
+        if (leadingComments)
+            destEmitNode.leadingComments = ts.addRange(leadingComments.slice(), destEmitNode.leadingComments);
+        if (trailingComments)
+            destEmitNode.trailingComments = ts.addRange(trailingComments.slice(), destEmitNode.trailingComments);
+        if (flags)
+            destEmitNode.flags = flags;
+        if (commentRange)
+            destEmitNode.commentRange = commentRange;
+        if (sourceMapRange)
+            destEmitNode.sourceMapRange = sourceMapRange;
+        if (tokenSourceMapRanges)
+            destEmitNode.tokenSourceMapRanges = mergeTokenSourceMapRanges(tokenSourceMapRanges, destEmitNode.tokenSourceMapRanges);
+        if (constantValue !== undefined)
+            destEmitNode.constantValue = constantValue;
+        if (helpers)
+            destEmitNode.helpers = ts.addRange(destEmitNode.helpers, helpers);
+        if (startsOnNewLine !== undefined)
+            destEmitNode.startsOnNewLine = startsOnNewLine;
+        return destEmitNode;
+    }
+    function mergeTokenSourceMapRanges(sourceRanges, destRanges) {
+        if (!destRanges)
+            destRanges = [];
+        for (var key in sourceRanges) {
+            destRanges[key] = sourceRanges[key];
+        }
+        return destRanges;
+    }
+})(ts || (ts = {}));
+/* @internal */
+(function (ts) {
+    ts.nullTransformationContext = {
+        enableEmitNotification: ts.noop,
+        enableSubstitution: ts.noop,
+        endLexicalEnvironment: function () { return undefined; },
+        getCompilerOptions: ts.notImplemented,
+        getEmitHost: ts.notImplemented,
+        getEmitResolver: ts.notImplemented,
+        hoistFunctionDeclaration: ts.noop,
+        hoistVariableDeclaration: ts.noop,
+        isEmitNotificationEnabled: ts.notImplemented,
+        isSubstitutionEnabled: ts.notImplemented,
+        onEmitNode: ts.noop,
+        onSubstituteNode: ts.notImplemented,
+        readEmitHelpers: ts.notImplemented,
+        requestEmitHelper: ts.noop,
+        resumeLexicalEnvironment: ts.noop,
+        startLexicalEnvironment: ts.noop,
+        suspendLexicalEnvironment: ts.noop,
+        addDiagnostic: ts.noop,
+    };
+    function createTypeCheck(value, tag) {
+        return tag === "undefined"
+            ? ts.createStrictEquality(value, ts.createVoidZero())
+            : ts.createStrictEquality(ts.createTypeOf(value), ts.createLiteral(tag));
+    }
+    ts.createTypeCheck = createTypeCheck;
+    function createMemberAccessForPropertyName(target, memberName, location) {
+        if (ts.isComputedPropertyName(memberName)) {
+            return ts.setTextRange(ts.createElementAccess(target, memberName.expression), location);
+        }
+        else {
+            var expression = ts.setTextRange(ts.isIdentifier(memberName)
+                ? ts.createPropertyAccess(target, memberName)
+                : ts.createElementAccess(target, memberName), memberName);
+            ts.getOrCreateEmitNode(expression).flags |= 64 /* NoNestedSourceMaps */;
+            return expression;
+        }
+    }
+    ts.createMemberAccessForPropertyName = createMemberAccessForPropertyName;
+    function createFunctionCall(func, thisArg, argumentsList, location) {
+        return ts.setTextRange(ts.createCall(ts.createPropertyAccess(func, "call"), 
+        /*typeArguments*/ undefined, [
+            thisArg
+        ].concat(argumentsList)), location);
+    }
+    ts.createFunctionCall = createFunctionCall;
+    function createFunctionApply(func, thisArg, argumentsExpression, location) {
+        return ts.setTextRange(ts.createCall(ts.createPropertyAccess(func, "apply"), 
+        /*typeArguments*/ undefined, [
+            thisArg,
+            argumentsExpression
+        ]), location);
+    }
+    ts.createFunctionApply = createFunctionApply;
+    function createArraySlice(array, start) {
+        var argumentsList = [];
+        if (start !== undefined) {
+            argumentsList.push(typeof start === "number" ? ts.createLiteral(start) : start);
+        }
+        return ts.createCall(ts.createPropertyAccess(array, "slice"), /*typeArguments*/ undefined, argumentsList);
+    }
+    ts.createArraySlice = createArraySlice;
+    function createArrayConcat(array, values) {
+        return ts.createCall(ts.createPropertyAccess(array, "concat"), 
+        /*typeArguments*/ undefined, values);
+    }
+    ts.createArrayConcat = createArrayConcat;
+    function createMathPow(left, right, location) {
+        return ts.setTextRange(ts.createCall(ts.createPropertyAccess(ts.createIdentifier("Math"), "pow"), 
+        /*typeArguments*/ undefined, [left, right]), location);
+    }
+    ts.createMathPow = createMathPow;
+    function createReactNamespace(reactNamespace, parent) {
+        // To ensure the emit resolver can properly resolve the namespace, we need to
+        // treat this identifier as if it were a source tree node by clearing the `Synthesized`
+        // flag and setting a parent node.
+        var react = ts.createIdentifier(reactNamespace || "React");
+        react.flags &= ~8 /* Synthesized */;
+        // Set the parent that is in parse tree
+        // this makes sure that parent chain is intact for checker to traverse complete scope tree
+        react.parent = ts.getParseTreeNode(parent);
+        return react;
+    }
+    function createJsxFactoryExpressionFromEntityName(jsxFactory, parent) {
+        if (ts.isQualifiedName(jsxFactory)) {
+            var left = createJsxFactoryExpressionFromEntityName(jsxFactory.left, parent);
+            var right = ts.createIdentifier(ts.idText(jsxFactory.right));
+            right.escapedText = jsxFactory.right.escapedText;
+            return ts.createPropertyAccess(left, right);
+        }
+        else {
+            return createReactNamespace(ts.idText(jsxFactory), parent);
+        }
+    }
+    function createJsxFactoryExpression(jsxFactoryEntity, reactNamespace, parent) {
+        return jsxFactoryEntity ?
+            createJsxFactoryExpressionFromEntityName(jsxFactoryEntity, parent) :
+            ts.createPropertyAccess(createReactNamespace(reactNamespace, parent), "createElement");
+    }
+    function createExpressionForJsxElement(jsxFactoryEntity, reactNamespace, tagName, props, children, parentElement, location) {
+        var argumentsList = [tagName];
+        if (props) {
+            argumentsList.push(props);
+        }
+        if (children && children.length > 0) {
+            if (!props) {
+                argumentsList.push(ts.createNull());
+            }
+            if (children.length > 1) {
+                for (var _i = 0, children_1 = children; _i < children_1.length; _i++) {
+                    var child = children_1[_i];
+                    startOnNewLine(child);
+                    argumentsList.push(child);
+                }
+            }
+            else {
+                argumentsList.push(children[0]);
+            }
+        }
+        return ts.setTextRange(ts.createCall(createJsxFactoryExpression(jsxFactoryEntity, reactNamespace, parentElement), 
+        /*typeArguments*/ undefined, argumentsList), location);
+    }
+    ts.createExpressionForJsxElement = createExpressionForJsxElement;
+    function createExpressionForJsxFragment(jsxFactoryEntity, reactNamespace, children, parentElement, location) {
+        var tagName = ts.createPropertyAccess(createReactNamespace(reactNamespace, parentElement), "Fragment");
+        var argumentsList = [tagName];
+        argumentsList.push(ts.createNull());
+        if (children && children.length > 0) {
+            if (children.length > 1) {
+                for (var _i = 0, children_2 = children; _i < children_2.length; _i++) {
+                    var child = children_2[_i];
+                    startOnNewLine(child);
+                    argumentsList.push(child);
+                }
+            }
+            else {
+                argumentsList.push(children[0]);
+            }
+        }
+        return ts.setTextRange(ts.createCall(createJsxFactoryExpression(jsxFactoryEntity, reactNamespace, parentElement), 
+        /*typeArguments*/ undefined, argumentsList), location);
+    }
+    ts.createExpressionForJsxFragment = createExpressionForJsxFragment;
+    // Helpers
+    function getHelperName(name) {
+        return ts.setEmitFlags(ts.createIdentifier(name), 4096 /* HelperName */ | 2 /* AdviseOnEmitNode */);
+    }
+    ts.getHelperName = getHelperName;
+    var valuesHelper = {
+        name: "typescript:values",
+        scoped: false,
+        text: "\n            var __values = (this && this.__values) || function (o) {\n                var m = typeof Symbol === \"function\" && o[Symbol.iterator], i = 0;\n                if (m) return m.call(o);\n                return {\n                    next: function () {\n                        if (o && i >= o.length) o = void 0;\n                        return { value: o && o[i++], done: !o };\n                    }\n                };\n            };"
+    };
+    function createValuesHelper(context, expression, location) {
+        context.requestEmitHelper(valuesHelper);
+        return ts.setTextRange(ts.createCall(getHelperName("__values"), 
+        /*typeArguments*/ undefined, [expression]), location);
+    }
+    ts.createValuesHelper = createValuesHelper;
+    var readHelper = {
+        name: "typescript:read",
+        scoped: false,
+        text: "\n            var __read = (this && this.__read) || function (o, n) {\n                var m = typeof Symbol === \"function\" && o[Symbol.iterator];\n                if (!m) return o;\n                var i = m.call(o), r, ar = [], e;\n                try {\n                    while ((n === void 0 || n-- > 0) && !(r = i.next()).done) ar.push(r.value);\n                }\n                catch (error) { e = { error: error }; }\n                finally {\n                    try {\n                        if (r && !r.done && (m = i[\"return\"])) m.call(i);\n                    }\n                    finally { if (e) throw e.error; }\n                }\n                return ar;\n            };"
+    };
+    function createReadHelper(context, iteratorRecord, count, location) {
+        context.requestEmitHelper(readHelper);
+        return ts.setTextRange(ts.createCall(getHelperName("__read"), 
+        /*typeArguments*/ undefined, count !== undefined
+            ? [iteratorRecord, ts.createLiteral(count)]
+            : [iteratorRecord]), location);
+    }
+    ts.createReadHelper = createReadHelper;
+    var spreadHelper = {
+        name: "typescript:spread",
+        scoped: false,
+        text: "\n            var __spread = (this && this.__spread) || function () {\n                for (var ar = [], i = 0; i < arguments.length; i++) ar = ar.concat(__read(arguments[i]));\n                return ar;\n            };"
+    };
+    function createSpreadHelper(context, argumentList, location) {
+        context.requestEmitHelper(readHelper);
+        context.requestEmitHelper(spreadHelper);
+        return ts.setTextRange(ts.createCall(getHelperName("__spread"), 
+        /*typeArguments*/ undefined, argumentList), location);
+    }
+    ts.createSpreadHelper = createSpreadHelper;
+    // Utilities
+    function createForOfBindingStatement(node, boundValue) {
+        if (ts.isVariableDeclarationList(node)) {
+            var firstDeclaration = ts.first(node.declarations);
+            var updatedDeclaration = ts.updateVariableDeclaration(firstDeclaration, firstDeclaration.name, 
+            /*typeNode*/ undefined, boundValue);
+            return ts.setTextRange(ts.createVariableStatement(
+            /*modifiers*/ undefined, ts.updateVariableDeclarationList(node, [updatedDeclaration])), 
+            /*location*/ node);
+        }
+        else {
+            var updatedExpression = ts.setTextRange(ts.createAssignment(node, boundValue), /*location*/ node);
+            return ts.setTextRange(ts.createStatement(updatedExpression), /*location*/ node);
+        }
+    }
+    ts.createForOfBindingStatement = createForOfBindingStatement;
+    function insertLeadingStatement(dest, source) {
+        if (ts.isBlock(dest)) {
+            return ts.updateBlock(dest, ts.setTextRange(ts.createNodeArray([source].concat(dest.statements)), dest.statements));
+        }
+        else {
+            return ts.createBlock(ts.createNodeArray([dest, source]), /*multiLine*/ true);
+        }
+    }
+    ts.insertLeadingStatement = insertLeadingStatement;
+    function restoreEnclosingLabel(node, outermostLabeledStatement, afterRestoreLabelCallback) {
+        if (!outermostLabeledStatement) {
+            return node;
+        }
+        var updated = ts.updateLabel(outermostLabeledStatement, outermostLabeledStatement.label, outermostLabeledStatement.statement.kind === 228 /* LabeledStatement */
+            ? restoreEnclosingLabel(node, outermostLabeledStatement.statement)
+            : node);
+        if (afterRestoreLabelCallback) {
+            afterRestoreLabelCallback(outermostLabeledStatement);
+        }
+        return updated;
+    }
+    ts.restoreEnclosingLabel = restoreEnclosingLabel;
+    function shouldBeCapturedInTempVariable(node, cacheIdentifiers) {
+        var target = ts.skipParentheses(node);
+        switch (target.kind) {
+            case 71 /* Identifier */:
+                return cacheIdentifiers;
+            case 99 /* ThisKeyword */:
+            case 8 /* NumericLiteral */:
+            case 9 /* StringLiteral */:
+                return false;
+            case 183 /* ArrayLiteralExpression */:
+                var elements = target.elements;
+                if (elements.length === 0) {
+                    return false;
+                }
+                return true;
+            case 184 /* ObjectLiteralExpression */:
+                return target.properties.length > 0;
+            default:
+                return true;
+        }
+    }
+    function createCallBinding(expression, recordTempVariable, languageVersion, cacheIdentifiers) {
+        if (cacheIdentifiers === void 0) { cacheIdentifiers = false; }
+        var callee = skipOuterExpressions(expression, 7 /* All */);
+        var thisArg;
+        var target;
+        if (ts.isSuperProperty(callee)) {
+            thisArg = ts.createThis();
+            target = callee;
+        }
+        else if (callee.kind === 97 /* SuperKeyword */) {
+            thisArg = ts.createThis();
+            target = languageVersion < 2 /* ES2015 */
+                ? ts.setTextRange(ts.createIdentifier("_super"), callee)
+                : callee;
+        }
+        else if (ts.getEmitFlags(callee) & 4096 /* HelperName */) {
+            thisArg = ts.createVoidZero();
+            target = parenthesizeForAccess(callee);
+        }
+        else {
+            switch (callee.kind) {
+                case 185 /* PropertyAccessExpression */: {
+                    if (shouldBeCapturedInTempVariable(callee.expression, cacheIdentifiers)) {
+                        // for `a.b()` target is `(_a = a).b` and thisArg is `_a`
+                        thisArg = ts.createTempVariable(recordTempVariable);
+                        target = ts.createPropertyAccess(ts.setTextRange(ts.createAssignment(thisArg, callee.expression), callee.expression), callee.name);
+                        ts.setTextRange(target, callee);
+                    }
+                    else {
+                        thisArg = callee.expression;
+                        target = callee;
+                    }
+                    break;
+                }
+                case 186 /* ElementAccessExpression */: {
+                    if (shouldBeCapturedInTempVariable(callee.expression, cacheIdentifiers)) {
+                        // for `a[b]()` target is `(_a = a)[b]` and thisArg is `_a`
+                        thisArg = ts.createTempVariable(recordTempVariable);
+                        target = ts.createElementAccess(ts.setTextRange(ts.createAssignment(thisArg, callee.expression), callee.expression), callee.argumentExpression);
+                        ts.setTextRange(target, callee);
+                    }
+                    else {
+                        thisArg = callee.expression;
+                        target = callee;
+                    }
+                    break;
+                }
+                default: {
+                    // for `a()` target is `a` and thisArg is `void 0`
+                    thisArg = ts.createVoidZero();
+                    target = parenthesizeForAccess(expression);
+                    break;
+                }
+            }
+        }
+        return { target: target, thisArg: thisArg };
+    }
+    ts.createCallBinding = createCallBinding;
+    function inlineExpressions(expressions) {
+        // Avoid deeply nested comma expressions as traversing them during emit can result in "Maximum call
+        // stack size exceeded" errors.
+        return expressions.length > 10
+            ? ts.createCommaList(expressions)
+            : ts.reduceLeft(expressions, ts.createComma);
+    }
+    ts.inlineExpressions = inlineExpressions;
+    function createExpressionFromEntityName(node) {
+        if (ts.isQualifiedName(node)) {
+            var left = createExpressionFromEntityName(node.left);
+            var right = ts.getMutableClone(node.right);
+            return ts.setTextRange(ts.createPropertyAccess(left, right), node);
+        }
+        else {
+            return ts.getMutableClone(node);
+        }
+    }
+    ts.createExpressionFromEntityName = createExpressionFromEntityName;
+    function createExpressionForPropertyName(memberName) {
+        if (ts.isIdentifier(memberName)) {
+            return ts.createLiteral(memberName);
+        }
+        else if (ts.isComputedPropertyName(memberName)) {
+            return ts.getMutableClone(memberName.expression);
+        }
+        else {
+            return ts.getMutableClone(memberName);
+        }
+    }
+    ts.createExpressionForPropertyName = createExpressionForPropertyName;
+    function createExpressionForObjectLiteralElementLike(node, property, receiver) {
+        switch (property.kind) {
+            case 156 /* GetAccessor */:
+            case 157 /* SetAccessor */:
+                return createExpressionForAccessorDeclaration(node.properties, property, receiver, !!node.multiLine);
+            case 270 /* PropertyAssignment */:
+                return createExpressionForPropertyAssignment(property, receiver);
+            case 271 /* ShorthandPropertyAssignment */:
+                return createExpressionForShorthandPropertyAssignment(property, receiver);
+            case 154 /* MethodDeclaration */:
+                return createExpressionForMethodDeclaration(property, receiver);
+        }
+    }
+    ts.createExpressionForObjectLiteralElementLike = createExpressionForObjectLiteralElementLike;
+    function createExpressionForAccessorDeclaration(properties, property, receiver, multiLine) {
+        var _a = ts.getAllAccessorDeclarations(properties, property), firstAccessor = _a.firstAccessor, getAccessor = _a.getAccessor, setAccessor = _a.setAccessor;
+        if (property === firstAccessor) {
+            var properties_9 = [];
+            if (getAccessor) {
+                var getterFunction = ts.createFunctionExpression(getAccessor.modifiers, 
+                /*asteriskToken*/ undefined, 
+                /*name*/ undefined, 
+                /*typeParameters*/ undefined, getAccessor.parameters, 
+                /*type*/ undefined, getAccessor.body // TODO: GH#18217
+                );
+                ts.setTextRange(getterFunction, getAccessor);
+                ts.setOriginalNode(getterFunction, getAccessor);
+                var getter = ts.createPropertyAssignment("get", getterFunction);
+                properties_9.push(getter);
+            }
+            if (setAccessor) {
+                var setterFunction = ts.createFunctionExpression(setAccessor.modifiers, 
+                /*asteriskToken*/ undefined, 
+                /*name*/ undefined, 
+                /*typeParameters*/ undefined, setAccessor.parameters, 
+                /*type*/ undefined, setAccessor.body // TODO: GH#18217
+                );
+                ts.setTextRange(setterFunction, setAccessor);
+                ts.setOriginalNode(setterFunction, setAccessor);
+                var setter = ts.createPropertyAssignment("set", setterFunction);
+                properties_9.push(setter);
+            }
+            properties_9.push(ts.createPropertyAssignment("enumerable", ts.createTrue()));
+            properties_9.push(ts.createPropertyAssignment("configurable", ts.createTrue()));
+            var expression = ts.setTextRange(ts.createCall(ts.createPropertyAccess(ts.createIdentifier("Object"), "defineProperty"), 
+            /*typeArguments*/ undefined, [
+                receiver,
+                createExpressionForPropertyName(property.name),
+                ts.createObjectLiteral(properties_9, multiLine)
+            ]), 
+            /*location*/ firstAccessor);
+            return ts.aggregateTransformFlags(expression);
+        }
+        return undefined;
+    }
+    function createExpressionForPropertyAssignment(property, receiver) {
+        return ts.aggregateTransformFlags(ts.setOriginalNode(ts.setTextRange(ts.createAssignment(createMemberAccessForPropertyName(receiver, property.name, /*location*/ property.name), property.initializer), property), property));
+    }
+    function createExpressionForShorthandPropertyAssignment(property, receiver) {
+        return ts.aggregateTransformFlags(ts.setOriginalNode(ts.setTextRange(ts.createAssignment(createMemberAccessForPropertyName(receiver, property.name, /*location*/ property.name), ts.getSynthesizedClone(property.name)), 
+        /*location*/ property), 
+        /*original*/ property));
+    }
+    function createExpressionForMethodDeclaration(method, receiver) {
+        return ts.aggregateTransformFlags(ts.setOriginalNode(ts.setTextRange(ts.createAssignment(createMemberAccessForPropertyName(receiver, method.name, /*location*/ method.name), ts.setOriginalNode(ts.setTextRange(ts.createFunctionExpression(method.modifiers, method.asteriskToken, 
+        /*name*/ undefined, 
+        /*typeParameters*/ undefined, method.parameters, 
+        /*type*/ undefined, method.body // TODO: GH#18217
+        ), 
+        /*location*/ method), 
+        /*original*/ method)), 
+        /*location*/ method), 
+        /*original*/ method));
+    }
+    /**
+     * Gets the internal name of a declaration. This is primarily used for declarations that can be
+     * referred to by name in the body of an ES5 class function body. An internal name will *never*
+     * be prefixed with an module or namespace export modifier like "exports." when emitted as an
+     * expression. An internal name will also *never* be renamed due to a collision with a block
+     * scoped variable.
+     *
+     * @param node The declaration.
+     * @param allowComments A value indicating whether comments may be emitted for the name.
+     * @param allowSourceMaps A value indicating whether source maps may be emitted for the name.
+     */
+    function getInternalName(node, allowComments, allowSourceMaps) {
+        return getName(node, allowComments, allowSourceMaps, 16384 /* LocalName */ | 32768 /* InternalName */);
+    }
+    ts.getInternalName = getInternalName;
+    /**
+     * Gets whether an identifier should only be referred to by its internal name.
+     */
+    function isInternalName(node) {
+        return (ts.getEmitFlags(node) & 32768 /* InternalName */) !== 0;
+    }
+    ts.isInternalName = isInternalName;
+    /**
+     * Gets the local name of a declaration. This is primarily used for declarations that can be
+     * referred to by name in the declaration's immediate scope (classes, enums, namespaces). A
+     * local name will *never* be prefixed with an module or namespace export modifier like
+     * "exports." when emitted as an expression.
+     *
+     * @param node The declaration.
+     * @param allowComments A value indicating whether comments may be emitted for the name.
+     * @param allowSourceMaps A value indicating whether source maps may be emitted for the name.
+     */
+    function getLocalName(node, allowComments, allowSourceMaps) {
+        return getName(node, allowComments, allowSourceMaps, 16384 /* LocalName */);
+    }
+    ts.getLocalName = getLocalName;
+    /**
+     * Gets whether an identifier should only be referred to by its local name.
+     */
+    function isLocalName(node) {
+        return (ts.getEmitFlags(node) & 16384 /* LocalName */) !== 0;
+    }
+    ts.isLocalName = isLocalName;
+    /**
+     * Gets the export name of a declaration. This is primarily used for declarations that can be
+     * referred to by name in the declaration's immediate scope (classes, enums, namespaces). An
+     * export name will *always* be prefixed with an module or namespace export modifier like
+     * `"exports."` when emitted as an expression if the name points to an exported symbol.
+     *
+     * @param node The declaration.
+     * @param allowComments A value indicating whether comments may be emitted for the name.
+     * @param allowSourceMaps A value indicating whether source maps may be emitted for the name.
+     */
+    function getExportName(node, allowComments, allowSourceMaps) {
+        return getName(node, allowComments, allowSourceMaps, 8192 /* ExportName */);
+    }
+    ts.getExportName = getExportName;
+    /**
+     * Gets whether an identifier should only be referred to by its export representation if the
+     * name points to an exported symbol.
+     */
+    function isExportName(node) {
+        return (ts.getEmitFlags(node) & 8192 /* ExportName */) !== 0;
+    }
+    ts.isExportName = isExportName;
+    /**
+     * Gets the name of a declaration for use in declarations.
+     *
+     * @param node The declaration.
+     * @param allowComments A value indicating whether comments may be emitted for the name.
+     * @param allowSourceMaps A value indicating whether source maps may be emitted for the name.
+     */
+    function getDeclarationName(node, allowComments, allowSourceMaps) {
+        return getName(node, allowComments, allowSourceMaps);
+    }
+    ts.getDeclarationName = getDeclarationName;
+    function getName(node, allowComments, allowSourceMaps, emitFlags) {
+        if (emitFlags === void 0) { emitFlags = 0; }
+        var nodeName = ts.getNameOfDeclaration(node);
+        if (nodeName && ts.isIdentifier(nodeName) && !ts.isGeneratedIdentifier(nodeName)) {
+            var name = ts.getMutableClone(nodeName);
+            emitFlags |= ts.getEmitFlags(nodeName);
+            if (!allowSourceMaps)
+                emitFlags |= 48 /* NoSourceMap */;
+            if (!allowComments)
+                emitFlags |= 1536 /* NoComments */;
+            if (emitFlags)
+                ts.setEmitFlags(name, emitFlags);
+            return name;
+        }
+        return ts.getGeneratedNameForNode(node);
+    }
+    /**
+     * Gets the exported name of a declaration for use in expressions.
+     *
+     * An exported name will *always* be prefixed with an module or namespace export modifier like
+     * "exports." if the name points to an exported symbol.
+     *
+     * @param ns The namespace identifier.
+     * @param node The declaration.
+     * @param allowComments A value indicating whether comments may be emitted for the name.
+     * @param allowSourceMaps A value indicating whether source maps may be emitted for the name.
+     */
+    function getExternalModuleOrNamespaceExportName(ns, node, allowComments, allowSourceMaps) {
+        if (ns && ts.hasModifier(node, 1 /* Export */)) {
+            return getNamespaceMemberName(ns, getName(node), allowComments, allowSourceMaps);
+        }
+        return getExportName(node, allowComments, allowSourceMaps);
+    }
+    ts.getExternalModuleOrNamespaceExportName = getExternalModuleOrNamespaceExportName;
+    /**
+     * Gets a namespace-qualified name for use in expressions.
+     *
+     * @param ns The namespace identifier.
+     * @param name The name.
+     * @param allowComments A value indicating whether comments may be emitted for the name.
+     * @param allowSourceMaps A value indicating whether source maps may be emitted for the name.
+     */
+    function getNamespaceMemberName(ns, name, allowComments, allowSourceMaps) {
+        var qualifiedName = ts.createPropertyAccess(ns, ts.nodeIsSynthesized(name) ? name : ts.getSynthesizedClone(name));
+        ts.setTextRange(qualifiedName, name);
+        var emitFlags = 0;
+        if (!allowSourceMaps)
+            emitFlags |= 48 /* NoSourceMap */;
+        if (!allowComments)
+            emitFlags |= 1536 /* NoComments */;
+        if (emitFlags)
+            ts.setEmitFlags(qualifiedName, emitFlags);
+        return qualifiedName;
+    }
+    ts.getNamespaceMemberName = getNamespaceMemberName;
+    function convertToFunctionBody(node, multiLine) {
+        return ts.isBlock(node) ? node : ts.setTextRange(ts.createBlock([ts.setTextRange(ts.createReturn(node), node)], multiLine), node);
+    }
+    ts.convertToFunctionBody = convertToFunctionBody;
+    function convertFunctionDeclarationToExpression(node) {
+        if (!node.body)
+            return ts.Debug.fail();
+        var updated = ts.createFunctionExpression(node.modifiers, node.asteriskToken, node.name, node.typeParameters, node.parameters, node.type, node.body);
+        ts.setOriginalNode(updated, node);
+        ts.setTextRange(updated, node);
+        if (ts.getStartsOnNewLine(node)) {
+            ts.setStartsOnNewLine(updated, /*newLine*/ true);
+        }
+        ts.aggregateTransformFlags(updated);
+        return updated;
+    }
+    ts.convertFunctionDeclarationToExpression = convertFunctionDeclarationToExpression;
+    function isUseStrictPrologue(node) {
+        return ts.isStringLiteral(node.expression) && node.expression.text === "use strict";
+    }
+    /**
+     * Add any necessary prologue-directives into target statement-array.
+     * The function needs to be called during each transformation step.
+     * This function needs to be called whenever we transform the statement
+     * list of a source file, namespace, or function-like body.
+     *
+     * @param target: result statements array
+     * @param source: origin statements array
+     * @param ensureUseStrict: boolean determining whether the function need to add prologue-directives
+     * @param visitor: Optional callback used to visit any custom prologue directives.
+     */
+    function addPrologue(target, source, ensureUseStrict, visitor) {
+        var offset = addStandardPrologue(target, source, ensureUseStrict);
+        return addCustomPrologue(target, source, offset, visitor);
+    }
+    ts.addPrologue = addPrologue;
+    /**
+     * Add just the standard (string-expression) prologue-directives into target statement-array.
+     * The function needs to be called during each transformation step.
+     * This function needs to be called whenever we transform the statement
+     * list of a source file, namespace, or function-like body.
+     */
+    function addStandardPrologue(target, source, ensureUseStrict) {
+        ts.Debug.assert(target.length === 0, "Prologue directives should be at the first statement in the target statements array");
+        var foundUseStrict = false;
+        var statementOffset = 0;
+        var numStatements = source.length;
+        while (statementOffset < numStatements) {
+            var statement = source[statementOffset];
+            if (ts.isPrologueDirective(statement)) {
+                if (isUseStrictPrologue(statement)) {
+                    foundUseStrict = true;
+                }
+                target.push(statement);
+            }
+            else {
+                break;
+            }
+            statementOffset++;
+        }
+        if (ensureUseStrict && !foundUseStrict) {
+            target.push(startOnNewLine(ts.createStatement(ts.createLiteral("use strict"))));
+        }
+        return statementOffset;
+    }
+    ts.addStandardPrologue = addStandardPrologue;
+    function addCustomPrologue(target, source, statementOffset, visitor) {
+        var numStatements = source.length;
+        while (statementOffset !== undefined && statementOffset < numStatements) {
+            var statement = source[statementOffset];
+            if (ts.getEmitFlags(statement) & 1048576 /* CustomPrologue */) {
+                ts.append(target, visitor ? ts.visitNode(statement, visitor, ts.isStatement) : statement);
+            }
+            else {
+                break;
+            }
+            statementOffset++;
+        }
+        return statementOffset;
+    }
+    ts.addCustomPrologue = addCustomPrologue;
+    function startsWithUseStrict(statements) {
+        var firstStatement = ts.firstOrUndefined(statements);
+        return firstStatement !== undefined
+            && ts.isPrologueDirective(firstStatement)
+            && isUseStrictPrologue(firstStatement);
+    }
+    ts.startsWithUseStrict = startsWithUseStrict;
+    /**
+     * Ensures "use strict" directive is added
+     *
+     * @param statements An array of statements
+     */
+    function ensureUseStrict(statements) {
+        var foundUseStrict = false;
+        for (var _i = 0, statements_3 = statements; _i < statements_3.length; _i++) {
+            var statement = statements_3[_i];
+            if (ts.isPrologueDirective(statement)) {
+                if (isUseStrictPrologue(statement)) {
+                    foundUseStrict = true;
+                    break;
+                }
+            }
+            else {
+                break;
+            }
+        }
+        if (!foundUseStrict) {
+            return ts.setTextRange(ts.createNodeArray([
+                startOnNewLine(ts.createStatement(ts.createLiteral("use strict")))
+            ].concat(statements)), statements);
+        }
+        return statements;
+    }
+    ts.ensureUseStrict = ensureUseStrict;
+    /**
+     * Wraps the operand to a BinaryExpression in parentheses if they are needed to preserve the intended
+     * order of operations.
+     *
+     * @param binaryOperator The operator for the BinaryExpression.
+     * @param operand The operand for the BinaryExpression.
+     * @param isLeftSideOfBinary A value indicating whether the operand is the left side of the
+     *                           BinaryExpression.
+     */
+    function parenthesizeBinaryOperand(binaryOperator, operand, isLeftSideOfBinary, leftOperand) {
+        var skipped = ts.skipPartiallyEmittedExpressions(operand);
+        // If the resulting expression is already parenthesized, we do not need to do any further processing.
+        if (skipped.kind === 191 /* ParenthesizedExpression */) {
+            return operand;
+        }
+        return binaryOperandNeedsParentheses(binaryOperator, operand, isLeftSideOfBinary, leftOperand)
+            ? ts.createParen(operand)
+            : operand;
+    }
+    ts.parenthesizeBinaryOperand = parenthesizeBinaryOperand;
+    /**
+     * Determines whether the operand to a BinaryExpression needs to be parenthesized.
+     *
+     * @param binaryOperator The operator for the BinaryExpression.
+     * @param operand The operand for the BinaryExpression.
+     * @param isLeftSideOfBinary A value indicating whether the operand is the left side of the
+     *                           BinaryExpression.
+     */
+    function binaryOperandNeedsParentheses(binaryOperator, operand, isLeftSideOfBinary, leftOperand) {
+        // If the operand has lower precedence, then it needs to be parenthesized to preserve the
+        // intent of the expression. For example, if the operand is `a + b` and the operator is
+        // `*`, then we need to parenthesize the operand to preserve the intended order of
+        // operations: `(a + b) * x`.
+        //
+        // If the operand has higher precedence, then it does not need to be parenthesized. For
+        // example, if the operand is `a * b` and the operator is `+`, then we do not need to
+        // parenthesize to preserve the intended order of operations: `a * b + x`.
+        //
+        // If the operand has the same precedence, then we need to check the associativity of
+        // the operator based on whether this is the left or right operand of the expression.
+        //
+        // For example, if `a / d` is on the right of operator `*`, we need to parenthesize
+        // to preserve the intended order of operations: `x * (a / d)`
+        //
+        // If `a ** d` is on the left of operator `**`, we need to parenthesize to preserve
+        // the intended order of operations: `(a ** b) ** c`
+        var binaryOperatorPrecedence = ts.getOperatorPrecedence(200 /* BinaryExpression */, binaryOperator);
+        var binaryOperatorAssociativity = ts.getOperatorAssociativity(200 /* BinaryExpression */, binaryOperator);
+        var emittedOperand = ts.skipPartiallyEmittedExpressions(operand);
+        var operandPrecedence = ts.getExpressionPrecedence(emittedOperand);
+        switch (ts.compareValues(operandPrecedence, binaryOperatorPrecedence)) {
+            case -1 /* LessThan */:
+                // If the operand is the right side of a right-associative binary operation
+                // and is a yield expression, then we do not need parentheses.
+                if (!isLeftSideOfBinary
+                    && binaryOperatorAssociativity === 1 /* Right */
+                    && operand.kind === 203 /* YieldExpression */) {
+                    return false;
+                }
+                return true;
+            case 1 /* GreaterThan */:
+                return false;
+            case 0 /* EqualTo */:
+                if (isLeftSideOfBinary) {
+                    // No need to parenthesize the left operand when the binary operator is
+                    // left associative:
+                    //  (a*b)/x    -> a*b/x
+                    //  (a**b)/x   -> a**b/x
+                    //
+                    // Parentheses are needed for the left operand when the binary operator is
+                    // right associative:
+                    //  (a/b)**x   -> (a/b)**x
+                    //  (a**b)**x  -> (a**b)**x
+                    return binaryOperatorAssociativity === 1 /* Right */;
+                }
+                else {
+                    if (ts.isBinaryExpression(emittedOperand)
+                        && emittedOperand.operatorToken.kind === binaryOperator) {
+                        // No need to parenthesize the right operand when the binary operator and
+                        // operand are the same and one of the following:
+                        //  x*(a*b)     => x*a*b
+                        //  x|(a|b)     => x|a|b
+                        //  x&(a&b)     => x&a&b
+                        //  x^(a^b)     => x^a^b
+                        if (operatorHasAssociativeProperty(binaryOperator)) {
+                            return false;
+                        }
+                        // No need to parenthesize the right operand when the binary operator
+                        // is plus (+) if both the left and right operands consist solely of either
+                        // literals of the same kind or binary plus (+) expressions for literals of
+                        // the same kind (recursively).
+                        //  "a"+(1+2)       => "a"+(1+2)
+                        //  "a"+("b"+"c")   => "a"+"b"+"c"
+                        if (binaryOperator === 37 /* PlusToken */) {
+                            var leftKind = leftOperand ? getLiteralKindOfBinaryPlusOperand(leftOperand) : 0 /* Unknown */;
+                            if (ts.isLiteralKind(leftKind) && leftKind === getLiteralKindOfBinaryPlusOperand(emittedOperand)) {
+                                return false;
+                            }
+                        }
+                    }
+                    // No need to parenthesize the right operand when the operand is right
+                    // associative:
+                    //  x/(a**b)    -> x/a**b
+                    //  x**(a**b)   -> x**a**b
+                    //
+                    // Parentheses are needed for the right operand when the operand is left
+                    // associative:
+                    //  x/(a*b)     -> x/(a*b)
+                    //  x**(a/b)    -> x**(a/b)
+                    var operandAssociativity = ts.getExpressionAssociativity(emittedOperand);
+                    return operandAssociativity === 0 /* Left */;
+                }
+        }
+    }
+    /**
+     * Determines whether a binary operator is mathematically associative.
+     *
+     * @param binaryOperator The binary operator.
+     */
+    function operatorHasAssociativeProperty(binaryOperator) {
+        // The following operators are associative in JavaScript:
+        //  (a*b)*c     -> a*(b*c)  -> a*b*c
+        //  (a|b)|c     -> a|(b|c)  -> a|b|c
+        //  (a&b)&c     -> a&(b&c)  -> a&b&c
+        //  (a^b)^c     -> a^(b^c)  -> a^b^c
+        //
+        // While addition is associative in mathematics, JavaScript's `+` is not
+        // guaranteed to be associative as it is overloaded with string concatenation.
+        return binaryOperator === 39 /* AsteriskToken */
+            || binaryOperator === 49 /* BarToken */
+            || binaryOperator === 48 /* AmpersandToken */
+            || binaryOperator === 50 /* CaretToken */;
+    }
+    /**
+     * This function determines whether an expression consists of a homogeneous set of
+     * literal expressions or binary plus expressions that all share the same literal kind.
+     * It is used to determine whether the right-hand operand of a binary plus expression can be
+     * emitted without parentheses.
+     */
+    function getLiteralKindOfBinaryPlusOperand(node) {
+        node = ts.skipPartiallyEmittedExpressions(node);
+        if (ts.isLiteralKind(node.kind)) {
+            return node.kind;
+        }
+        if (node.kind === 200 /* BinaryExpression */ && node.operatorToken.kind === 37 /* PlusToken */) {
+            if (node.cachedLiteralKind !== undefined) {
+                return node.cachedLiteralKind;
+            }
+            var leftKind = getLiteralKindOfBinaryPlusOperand(node.left);
+            var literalKind = ts.isLiteralKind(leftKind)
+                && leftKind === getLiteralKindOfBinaryPlusOperand(node.right)
+                ? leftKind
+                : 0 /* Unknown */;
+            node.cachedLiteralKind = literalKind;
+            return literalKind;
+        }
+        return 0 /* Unknown */;
+    }
+    function parenthesizeForConditionalHead(condition) {
+        var conditionalPrecedence = ts.getOperatorPrecedence(201 /* ConditionalExpression */, 55 /* QuestionToken */);
+        var emittedCondition = ts.skipPartiallyEmittedExpressions(condition);
+        var conditionPrecedence = ts.getExpressionPrecedence(emittedCondition);
+        if (ts.compareValues(conditionPrecedence, conditionalPrecedence) === -1 /* LessThan */) {
+            return ts.createParen(condition);
+        }
+        return condition;
+    }
+    ts.parenthesizeForConditionalHead = parenthesizeForConditionalHead;
+    function parenthesizeSubexpressionOfConditionalExpression(e) {
+        // per ES grammar both 'whenTrue' and 'whenFalse' parts of conditional expression are assignment expressions
+        // so in case when comma expression is introduced as a part of previous transformations
+        // if should be wrapped in parens since comma operator has the lowest precedence
+        var emittedExpression = ts.skipPartiallyEmittedExpressions(e);
+        return emittedExpression.kind === 200 /* BinaryExpression */ && emittedExpression.operatorToken.kind === 26 /* CommaToken */ ||
+            emittedExpression.kind === 302 /* CommaListExpression */
+            ? ts.createParen(e)
+            : e;
+    }
+    ts.parenthesizeSubexpressionOfConditionalExpression = parenthesizeSubexpressionOfConditionalExpression;
+    /**
+     *  [Per the spec](https://tc39.github.io/ecma262/#prod-ExportDeclaration), `export default` accepts _AssigmentExpression_ but
+     *  has a lookahead restriction for `function`, `async function`, and `class`.
+     *
+     * Basically, that means we need to parenthesize in the following cases:
+     *
+     * - BinaryExpression of CommaToken
+     * - CommaList (synthetic list of multiple comma expressions)
+     * - FunctionExpression
+     * - ClassExpression
+     */
+    function parenthesizeDefaultExpression(e) {
+        var check = ts.skipPartiallyEmittedExpressions(e);
+        return (check.kind === 205 /* ClassExpression */ ||
+            check.kind === 192 /* FunctionExpression */ ||
+            check.kind === 302 /* CommaListExpression */ ||
+            ts.isBinaryExpression(check) && check.operatorToken.kind === 26 /* CommaToken */)
+            ? ts.createParen(e)
+            : e;
+    }
+    ts.parenthesizeDefaultExpression = parenthesizeDefaultExpression;
+    /**
+     * Wraps an expression in parentheses if it is needed in order to use the expression
+     * as the expression of a NewExpression node.
+     *
+     * @param expression The Expression node.
+     */
+    function parenthesizeForNew(expression) {
+        var leftmostExpr = getLeftmostExpression(expression, /*stopAtCallExpressions*/ true);
+        switch (leftmostExpr.kind) {
+            case 187 /* CallExpression */:
+                return ts.createParen(expression);
+            case 188 /* NewExpression */:
+                return !leftmostExpr.arguments
+                    ? ts.createParen(expression)
+                    : expression;
+        }
+        return parenthesizeForAccess(expression);
+    }
+    ts.parenthesizeForNew = parenthesizeForNew;
+    /**
+     * Wraps an expression in parentheses if it is needed in order to use the expression for
+     * property or element access.
+     *
+     * @param expr The expression node.
+     */
+    function parenthesizeForAccess(expression) {
+        // isLeftHandSideExpression is almost the correct criterion for when it is not necessary
+        // to parenthesize the expression before a dot. The known exception is:
+        //
+        //    NewExpression:
+        //       new C.x        -> not the same as (new C).x
+        //
+        var emittedExpression = ts.skipPartiallyEmittedExpressions(expression);
+        if (ts.isLeftHandSideExpression(emittedExpression)
+            && (emittedExpression.kind !== 188 /* NewExpression */ || emittedExpression.arguments)) {
+            return expression;
+        }
+        return ts.setTextRange(ts.createParen(expression), expression);
+    }
+    ts.parenthesizeForAccess = parenthesizeForAccess;
+    function parenthesizePostfixOperand(operand) {
+        return ts.isLeftHandSideExpression(operand)
+            ? operand
+            : ts.setTextRange(ts.createParen(operand), operand);
+    }
+    ts.parenthesizePostfixOperand = parenthesizePostfixOperand;
+    function parenthesizePrefixOperand(operand) {
+        return ts.isUnaryExpression(operand)
+            ? operand
+            : ts.setTextRange(ts.createParen(operand), operand);
+    }
+    ts.parenthesizePrefixOperand = parenthesizePrefixOperand;
+    function parenthesizeListElements(elements) {
+        var result;
+        for (var i = 0; i < elements.length; i++) {
+            var element = parenthesizeExpressionForList(elements[i]);
+            if (result !== undefined || element !== elements[i]) {
+                if (result === undefined) {
+                    result = elements.slice(0, i);
+                }
+                result.push(element);
+            }
+        }
+        if (result !== undefined) {
+            return ts.setTextRange(ts.createNodeArray(result, elements.hasTrailingComma), elements);
+        }
+        return elements;
+    }
+    ts.parenthesizeListElements = parenthesizeListElements;
+    function parenthesizeExpressionForList(expression) {
+        var emittedExpression = ts.skipPartiallyEmittedExpressions(expression);
+        var expressionPrecedence = ts.getExpressionPrecedence(emittedExpression);
+        var commaPrecedence = ts.getOperatorPrecedence(200 /* BinaryExpression */, 26 /* CommaToken */);
+        return expressionPrecedence > commaPrecedence
+            ? expression
+            : ts.setTextRange(ts.createParen(expression), expression);
+    }
+    ts.parenthesizeExpressionForList = parenthesizeExpressionForList;
+    function parenthesizeExpressionForExpressionStatement(expression) {
+        var emittedExpression = ts.skipPartiallyEmittedExpressions(expression);
+        if (ts.isCallExpression(emittedExpression)) {
+            var callee = emittedExpression.expression;
+            var kind = ts.skipPartiallyEmittedExpressions(callee).kind;
+            if (kind === 192 /* FunctionExpression */ || kind === 193 /* ArrowFunction */) {
+                var mutableCall = ts.getMutableClone(emittedExpression);
+                mutableCall.expression = ts.setTextRange(ts.createParen(callee), callee);
+                return recreateOuterExpressions(expression, mutableCall, 4 /* PartiallyEmittedExpressions */);
+            }
+        }
+        var leftmostExpressionKind = getLeftmostExpression(emittedExpression, /*stopAtCallExpressions*/ false).kind;
+        if (leftmostExpressionKind === 184 /* ObjectLiteralExpression */ || leftmostExpressionKind === 192 /* FunctionExpression */) {
+            return ts.setTextRange(ts.createParen(expression), expression);
+        }
+        return expression;
+    }
+    ts.parenthesizeExpressionForExpressionStatement = parenthesizeExpressionForExpressionStatement;
+    function parenthesizeConditionalTypeMember(member) {
+        return member.kind === 171 /* ConditionalType */ ? ts.createParenthesizedType(member) : member;
+    }
+    ts.parenthesizeConditionalTypeMember = parenthesizeConditionalTypeMember;
+    function parenthesizeElementTypeMember(member) {
+        switch (member.kind) {
+            case 169 /* UnionType */:
+            case 170 /* IntersectionType */:
+            case 163 /* FunctionType */:
+            case 164 /* ConstructorType */:
+                return ts.createParenthesizedType(member);
+        }
+        return parenthesizeConditionalTypeMember(member);
+    }
+    ts.parenthesizeElementTypeMember = parenthesizeElementTypeMember;
+    function parenthesizeArrayTypeMember(member) {
+        switch (member.kind) {
+            case 165 /* TypeQuery */:
+            case 175 /* TypeOperator */:
+            case 172 /* InferType */:
+                return ts.createParenthesizedType(member);
+        }
+        return parenthesizeElementTypeMember(member);
+    }
+    ts.parenthesizeArrayTypeMember = parenthesizeArrayTypeMember;
+    function parenthesizeElementTypeMembers(members) {
+        return ts.createNodeArray(ts.sameMap(members, parenthesizeElementTypeMember));
+    }
+    ts.parenthesizeElementTypeMembers = parenthesizeElementTypeMembers;
+    function parenthesizeTypeParameters(typeParameters) {
+        if (ts.some(typeParameters)) {
+            var params = [];
+            for (var i = 0; i < typeParameters.length; ++i) {
+                var entry = typeParameters[i];
+                params.push(i === 0 && ts.isFunctionOrConstructorTypeNode(entry) && entry.typeParameters ?
+                    ts.createParenthesizedType(entry) :
+                    entry);
+            }
+            return ts.createNodeArray(params);
+        }
+    }
+    ts.parenthesizeTypeParameters = parenthesizeTypeParameters;
+    function getLeftmostExpression(node, stopAtCallExpressions) {
+        while (true) {
+            switch (node.kind) {
+                case 199 /* PostfixUnaryExpression */:
+                    node = node.operand;
+                    continue;
+                case 200 /* BinaryExpression */:
+                    node = node.left;
+                    continue;
+                case 201 /* ConditionalExpression */:
+                    node = node.condition;
+                    continue;
+                case 187 /* CallExpression */:
+                    if (stopAtCallExpressions) {
+                        return node;
+                    }
+                // falls through
+                case 186 /* ElementAccessExpression */:
+                case 185 /* PropertyAccessExpression */:
+                    node = node.expression;
+                    continue;
+                case 301 /* PartiallyEmittedExpression */:
+                    node = node.expression;
+                    continue;
+            }
+            return node;
+        }
+    }
+    function parenthesizeConciseBody(body) {
+        if (!ts.isBlock(body) && getLeftmostExpression(body, /*stopAtCallExpressions*/ false).kind === 184 /* ObjectLiteralExpression */) {
+            return ts.setTextRange(ts.createParen(body), body);
+        }
+        return body;
+    }
+    ts.parenthesizeConciseBody = parenthesizeConciseBody;
+    var OuterExpressionKinds;
+    (function (OuterExpressionKinds) {
+        OuterExpressionKinds[OuterExpressionKinds["Parentheses"] = 1] = "Parentheses";
+        OuterExpressionKinds[OuterExpressionKinds["Assertions"] = 2] = "Assertions";
+        OuterExpressionKinds[OuterExpressionKinds["PartiallyEmittedExpressions"] = 4] = "PartiallyEmittedExpressions";
+        OuterExpressionKinds[OuterExpressionKinds["All"] = 7] = "All";
+    })(OuterExpressionKinds = ts.OuterExpressionKinds || (ts.OuterExpressionKinds = {}));
+    function isOuterExpression(node, kinds) {
+        if (kinds === void 0) { kinds = 7 /* All */; }
+        switch (node.kind) {
+            case 191 /* ParenthesizedExpression */:
+                return (kinds & 1 /* Parentheses */) !== 0;
+            case 190 /* TypeAssertionExpression */:
+            case 208 /* AsExpression */:
+            case 209 /* NonNullExpression */:
+                return (kinds & 2 /* Assertions */) !== 0;
+            case 301 /* PartiallyEmittedExpression */:
+                return (kinds & 4 /* PartiallyEmittedExpressions */) !== 0;
+        }
+        return false;
+    }
+    ts.isOuterExpression = isOuterExpression;
+    function skipOuterExpressions(node, kinds) {
+        if (kinds === void 0) { kinds = 7 /* All */; }
+        var previousNode;
+        do {
+            previousNode = node;
+            if (kinds & 1 /* Parentheses */) {
+                node = ts.skipParentheses(node);
+            }
+            if (kinds & 2 /* Assertions */) {
+                node = skipAssertions(node);
+            }
+            if (kinds & 4 /* PartiallyEmittedExpressions */) {
+                node = ts.skipPartiallyEmittedExpressions(node);
+            }
+        } while (previousNode !== node);
+        return node;
+    }
+    ts.skipOuterExpressions = skipOuterExpressions;
+    function skipAssertions(node) {
+        while (ts.isAssertionExpression(node) || node.kind === 209 /* NonNullExpression */) {
+            node = node.expression;
+        }
+        return node;
+    }
+    ts.skipAssertions = skipAssertions;
+    function updateOuterExpression(outerExpression, expression) {
+        switch (outerExpression.kind) {
+            case 191 /* ParenthesizedExpression */: return ts.updateParen(outerExpression, expression);
+            case 190 /* TypeAssertionExpression */: return ts.updateTypeAssertion(outerExpression, outerExpression.type, expression);
+            case 208 /* AsExpression */: return ts.updateAsExpression(outerExpression, expression, outerExpression.type);
+            case 209 /* NonNullExpression */: return ts.updateNonNullExpression(outerExpression, expression);
+            case 301 /* PartiallyEmittedExpression */: return ts.updatePartiallyEmittedExpression(outerExpression, expression);
+        }
+    }
+    /**
+     * Determines whether a node is a parenthesized expression that can be ignored when recreating outer expressions.
+     *
+     * A parenthesized expression can be ignored when all of the following are true:
+     *
+     * - It's `pos` and `end` are not -1
+     * - It does not have a custom source map range
+     * - It does not have a custom comment range
+     * - It does not have synthetic leading or trailing comments
+     *
+     * If an outermost parenthesized expression is ignored, but the containing expression requires a parentheses around
+     * the expression to maintain precedence, a new parenthesized expression should be created automatically when
+     * the containing expression is created/updated.
+     */
+    function isIgnorableParen(node) {
+        return node.kind === 191 /* ParenthesizedExpression */
+            && ts.nodeIsSynthesized(node)
+            && ts.nodeIsSynthesized(ts.getSourceMapRange(node))
+            && ts.nodeIsSynthesized(ts.getCommentRange(node))
+            && !ts.some(ts.getSyntheticLeadingComments(node))
+            && !ts.some(ts.getSyntheticTrailingComments(node));
+    }
+    function recreateOuterExpressions(outerExpression, innerExpression, kinds) {
+        if (kinds === void 0) { kinds = 7 /* All */; }
+        if (outerExpression && isOuterExpression(outerExpression, kinds) && !isIgnorableParen(outerExpression)) {
+            return updateOuterExpression(outerExpression, recreateOuterExpressions(outerExpression.expression, innerExpression));
+        }
+        return innerExpression;
+    }
+    ts.recreateOuterExpressions = recreateOuterExpressions;
+    function startOnNewLine(node) {
+        return ts.setStartsOnNewLine(node, /*newLine*/ true);
+    }
+    ts.startOnNewLine = startOnNewLine;
+    function getExternalHelpersModuleName(node) {
+        var parseNode = ts.getOriginalNode(node, ts.isSourceFile);
+        var emitNode = parseNode && parseNode.emitNode;
+        return emitNode && emitNode.externalHelpersModuleName;
+    }
+    ts.getExternalHelpersModuleName = getExternalHelpersModuleName;
+    function getOrCreateExternalHelpersModuleNameIfNeeded(node, compilerOptions, hasExportStarsToExportValues, hasImportStarOrImportDefault) {
+        if (compilerOptions.importHelpers && ts.isEffectiveExternalModule(node, compilerOptions)) {
+            var externalHelpersModuleName = getExternalHelpersModuleName(node);
+            if (externalHelpersModuleName) {
+                return externalHelpersModuleName;
+            }
+            var moduleKind = ts.getEmitModuleKind(compilerOptions);
+            var create = (hasExportStarsToExportValues || (compilerOptions.esModuleInterop && hasImportStarOrImportDefault))
+                && moduleKind !== ts.ModuleKind.System
+                && moduleKind !== ts.ModuleKind.ES2015
+                && moduleKind !== ts.ModuleKind.ESNext;
+            if (!create) {
+                var helpers = ts.getEmitHelpers(node);
+                if (helpers) {
+                    for (var _i = 0, helpers_2 = helpers; _i < helpers_2.length; _i++) {
+                        var helper = helpers_2[_i];
+                        if (!helper.scoped) {
+                            create = true;
+                            break;
+                        }
+                    }
+                }
+            }
+            if (create) {
+                var parseNode = ts.getOriginalNode(node, ts.isSourceFile);
+                var emitNode = ts.getOrCreateEmitNode(parseNode);
+                return emitNode.externalHelpersModuleName || (emitNode.externalHelpersModuleName = ts.createUniqueName(ts.externalHelpersModuleNameText));
+            }
+        }
+    }
+    ts.getOrCreateExternalHelpersModuleNameIfNeeded = getOrCreateExternalHelpersModuleNameIfNeeded;
+    /**
+     * Get the name of that target module from an import or export declaration
+     */
+    function getLocalNameForExternalImport(node, sourceFile) {
+        var namespaceDeclaration = ts.getNamespaceDeclarationNode(node);
+        if (namespaceDeclaration && !ts.isDefaultImport(node)) {
+            var name = namespaceDeclaration.name;
+            return ts.isGeneratedIdentifier(name) ? name : ts.createIdentifier(ts.getSourceTextOfNodeFromSourceFile(sourceFile, name) || ts.idText(name));
+        }
+        if (node.kind === 244 /* ImportDeclaration */ && node.importClause) {
+            return ts.getGeneratedNameForNode(node);
+        }
+        if (node.kind === 250 /* ExportDeclaration */ && node.moduleSpecifier) {
+            return ts.getGeneratedNameForNode(node);
+        }
+        return undefined;
+    }
+    ts.getLocalNameForExternalImport = getLocalNameForExternalImport;
+    /**
+     * Get the name of a target module from an import/export declaration as should be written in the emitted output.
+     * The emitted output name can be different from the input if:
+     *  1. The module has a /// <amd-module name="<new name>" />
+     *  2. --out or --outFile is used, making the name relative to the rootDir
+     *  3- The containing SourceFile has an entry in renamedDependencies for the import as requested by some module loaders (e.g. System).
+     * Otherwise, a new StringLiteral node representing the module name will be returned.
+     */
+    function getExternalModuleNameLiteral(importNode, sourceFile, host, resolver, compilerOptions) {
+        var moduleName = ts.getExternalModuleName(importNode); // TODO: GH#18217
+        if (moduleName.kind === 9 /* StringLiteral */) {
+            return tryGetModuleNameFromDeclaration(importNode, host, resolver, compilerOptions)
+                || tryRenameExternalModule(moduleName, sourceFile)
+                || ts.getSynthesizedClone(moduleName);
+        }
+        return undefined;
+    }
+    ts.getExternalModuleNameLiteral = getExternalModuleNameLiteral;
+    /**
+     * Some bundlers (SystemJS builder) sometimes want to rename dependencies.
+     * Here we check if alternative name was provided for a given moduleName and return it if possible.
+     */
+    function tryRenameExternalModule(moduleName, sourceFile) {
+        var rename = sourceFile.renamedDependencies && sourceFile.renamedDependencies.get(moduleName.text);
+        return rename && ts.createLiteral(rename);
+    }
+    /**
+     * Get the name of a module as should be written in the emitted output.
+     * The emitted output name can be different from the input if:
+     *  1. The module has a /// <amd-module name="<new name>" />
+     *  2. --out or --outFile is used, making the name relative to the rootDir
+     * Otherwise, a new StringLiteral node representing the module name will be returned.
+     */
+    function tryGetModuleNameFromFile(file, host, options) {
+        if (!file) {
+            return undefined;
+        }
+        if (file.moduleName) {
+            return ts.createLiteral(file.moduleName);
+        }
+        if (!file.isDeclarationFile && (options.out || options.outFile)) {
+            return ts.createLiteral(ts.getExternalModuleNameFromPath(host, file.fileName));
+        }
+        return undefined;
+    }
+    ts.tryGetModuleNameFromFile = tryGetModuleNameFromFile;
+    function tryGetModuleNameFromDeclaration(declaration, host, resolver, compilerOptions) {
+        return tryGetModuleNameFromFile(resolver.getExternalModuleFileFromDeclaration(declaration), host, compilerOptions);
+    }
+    /**
+     * Gets the initializer of an BindingOrAssignmentElement.
+     */
+    function getInitializerOfBindingOrAssignmentElement(bindingElement) {
+        if (ts.isDeclarationBindingElement(bindingElement)) {
+            // `1` in `let { a = 1 } = ...`
+            // `1` in `let { a: b = 1 } = ...`
+            // `1` in `let { a: {b} = 1 } = ...`
+            // `1` in `let { a: [b] = 1 } = ...`
+            // `1` in `let [a = 1] = ...`
+            // `1` in `let [{a} = 1] = ...`
+            // `1` in `let [[a] = 1] = ...`
+            return bindingElement.initializer;
+        }
+        if (ts.isPropertyAssignment(bindingElement)) {
+            // `1` in `({ a: b = 1 } = ...)`
+            // `1` in `({ a: {b} = 1 } = ...)`
+            // `1` in `({ a: [b] = 1 } = ...)`
+            var initializer = bindingElement.initializer;
+            return ts.isAssignmentExpression(initializer, /*excludeCompoundAssignment*/ true)
+                ? initializer.right
+                : undefined;
+        }
+        if (ts.isShorthandPropertyAssignment(bindingElement)) {
+            // `1` in `({ a = 1 } = ...)`
+            return bindingElement.objectAssignmentInitializer;
+        }
+        if (ts.isAssignmentExpression(bindingElement, /*excludeCompoundAssignment*/ true)) {
+            // `1` in `[a = 1] = ...`
+            // `1` in `[{a} = 1] = ...`
+            // `1` in `[[a] = 1] = ...`
+            return bindingElement.right;
+        }
+        if (ts.isSpreadElement(bindingElement)) {
+            // Recovery consistent with existing emit.
+            return getInitializerOfBindingOrAssignmentElement(bindingElement.expression);
+        }
+    }
+    ts.getInitializerOfBindingOrAssignmentElement = getInitializerOfBindingOrAssignmentElement;
+    /**
+     * Gets the name of an BindingOrAssignmentElement.
+     */
+    function getTargetOfBindingOrAssignmentElement(bindingElement) {
+        if (ts.isDeclarationBindingElement(bindingElement)) {
+            // `a` in `let { a } = ...`
+            // `a` in `let { a = 1 } = ...`
+            // `b` in `let { a: b } = ...`
+            // `b` in `let { a: b = 1 } = ...`
+            // `a` in `let { ...a } = ...`
+            // `{b}` in `let { a: {b} } = ...`
+            // `{b}` in `let { a: {b} = 1 } = ...`
+            // `[b]` in `let { a: [b] } = ...`
+            // `[b]` in `let { a: [b] = 1 } = ...`
+            // `a` in `let [a] = ...`
+            // `a` in `let [a = 1] = ...`
+            // `a` in `let [...a] = ...`
+            // `{a}` in `let [{a}] = ...`
+            // `{a}` in `let [{a} = 1] = ...`
+            // `[a]` in `let [[a]] = ...`
+            // `[a]` in `let [[a] = 1] = ...`
+            return bindingElement.name;
+        }
+        if (ts.isObjectLiteralElementLike(bindingElement)) {
+            switch (bindingElement.kind) {
+                case 270 /* PropertyAssignment */:
+                    // `b` in `({ a: b } = ...)`
+                    // `b` in `({ a: b = 1 } = ...)`
+                    // `{b}` in `({ a: {b} } = ...)`
+                    // `{b}` in `({ a: {b} = 1 } = ...)`
+                    // `[b]` in `({ a: [b] } = ...)`
+                    // `[b]` in `({ a: [b] = 1 } = ...)`
+                    // `b.c` in `({ a: b.c } = ...)`
+                    // `b.c` in `({ a: b.c = 1 } = ...)`
+                    // `b[0]` in `({ a: b[0] } = ...)`
+                    // `b[0]` in `({ a: b[0] = 1 } = ...)`
+                    return getTargetOfBindingOrAssignmentElement(bindingElement.initializer);
+                case 271 /* ShorthandPropertyAssignment */:
+                    // `a` in `({ a } = ...)`
+                    // `a` in `({ a = 1 } = ...)`
+                    return bindingElement.name;
+                case 272 /* SpreadAssignment */:
+                    // `a` in `({ ...a } = ...)`
+                    return getTargetOfBindingOrAssignmentElement(bindingElement.expression);
+            }
+            // no target
+            return undefined;
+        }
+        if (ts.isAssignmentExpression(bindingElement, /*excludeCompoundAssignment*/ true)) {
+            // `a` in `[a = 1] = ...`
+            // `{a}` in `[{a} = 1] = ...`
+            // `[a]` in `[[a] = 1] = ...`
+            // `a.b` in `[a.b = 1] = ...`
+            // `a[0]` in `[a[0] = 1] = ...`
+            return getTargetOfBindingOrAssignmentElement(bindingElement.left);
+        }
+        if (ts.isSpreadElement(bindingElement)) {
+            // `a` in `[...a] = ...`
+            return getTargetOfBindingOrAssignmentElement(bindingElement.expression);
+        }
+        // `a` in `[a] = ...`
+        // `{a}` in `[{a}] = ...`
+        // `[a]` in `[[a]] = ...`
+        // `a.b` in `[a.b] = ...`
+        // `a[0]` in `[a[0]] = ...`
+        return bindingElement;
+    }
+    ts.getTargetOfBindingOrAssignmentElement = getTargetOfBindingOrAssignmentElement;
+    /**
+     * Determines whether an BindingOrAssignmentElement is a rest element.
+     */
+    function getRestIndicatorOfBindingOrAssignmentElement(bindingElement) {
+        switch (bindingElement.kind) {
+            case 149 /* Parameter */:
+            case 182 /* BindingElement */:
+                // `...` in `let [...a] = ...`
+                return bindingElement.dotDotDotToken;
+            case 204 /* SpreadElement */:
+            case 272 /* SpreadAssignment */:
+                // `...` in `[...a] = ...`
+                return bindingElement;
+        }
+        return undefined;
+    }
+    ts.getRestIndicatorOfBindingOrAssignmentElement = getRestIndicatorOfBindingOrAssignmentElement;
+    /**
+     * Gets the property name of a BindingOrAssignmentElement
+     */
+    function getPropertyNameOfBindingOrAssignmentElement(bindingElement) {
+        switch (bindingElement.kind) {
+            case 182 /* BindingElement */:
+                // `a` in `let { a: b } = ...`
+                // `[a]` in `let { [a]: b } = ...`
+                // `"a"` in `let { "a": b } = ...`
+                // `1` in `let { 1: b } = ...`
+                if (bindingElement.propertyName) {
+                    var propertyName = bindingElement.propertyName;
+                    return ts.isComputedPropertyName(propertyName) && ts.isStringOrNumericLiteral(propertyName.expression)
+                        ? propertyName.expression
+                        : propertyName;
+                }
+                break;
+            case 270 /* PropertyAssignment */:
+                // `a` in `({ a: b } = ...)`
+                // `[a]` in `({ [a]: b } = ...)`
+                // `"a"` in `({ "a": b } = ...)`
+                // `1` in `({ 1: b } = ...)`
+                if (bindingElement.name) {
+                    var propertyName = bindingElement.name;
+                    return ts.isComputedPropertyName(propertyName) && ts.isStringOrNumericLiteral(propertyName.expression)
+                        ? propertyName.expression
+                        : propertyName;
+                }
+                break;
+            case 272 /* SpreadAssignment */:
+                // `a` in `({ ...a } = ...)`
+                return bindingElement.name;
+        }
+        var target = getTargetOfBindingOrAssignmentElement(bindingElement);
+        if (target && ts.isPropertyName(target)) {
+            return ts.isComputedPropertyName(target) && ts.isStringOrNumericLiteral(target.expression)
+                ? target.expression
+                : target;
+        }
+        ts.Debug.fail("Invalid property name for binding element.");
+    }
+    ts.getPropertyNameOfBindingOrAssignmentElement = getPropertyNameOfBindingOrAssignmentElement;
+    /**
+     * Gets the elements of a BindingOrAssignmentPattern
+     */
+    function getElementsOfBindingOrAssignmentPattern(name) {
+        switch (name.kind) {
+            case 180 /* ObjectBindingPattern */:
+            case 181 /* ArrayBindingPattern */:
+            case 183 /* ArrayLiteralExpression */:
+                // `a` in `{a}`
+                // `a` in `[a]`
+                return name.elements;
+            case 184 /* ObjectLiteralExpression */:
+                // `a` in `{a}`
+                return name.properties;
+        }
+    }
+    ts.getElementsOfBindingOrAssignmentPattern = getElementsOfBindingOrAssignmentPattern;
+    function convertToArrayAssignmentElement(element) {
+        if (ts.isBindingElement(element)) {
+            if (element.dotDotDotToken) {
+                ts.Debug.assertNode(element.name, ts.isIdentifier);
+                return ts.setOriginalNode(ts.setTextRange(ts.createSpread(element.name), element), element);
+            }
+            var expression = convertToAssignmentElementTarget(element.name);
+            return element.initializer
+                ? ts.setOriginalNode(ts.setTextRange(ts.createAssignment(expression, element.initializer), element), element)
+                : expression;
+        }
+        ts.Debug.assertNode(element, ts.isExpression);
+        return element;
+    }
+    ts.convertToArrayAssignmentElement = convertToArrayAssignmentElement;
+    function convertToObjectAssignmentElement(element) {
+        if (ts.isBindingElement(element)) {
+            if (element.dotDotDotToken) {
+                ts.Debug.assertNode(element.name, ts.isIdentifier);
+                return ts.setOriginalNode(ts.setTextRange(ts.createSpreadAssignment(element.name), element), element);
+            }
+            if (element.propertyName) {
+                var expression = convertToAssignmentElementTarget(element.name);
+                return ts.setOriginalNode(ts.setTextRange(ts.createPropertyAssignment(element.propertyName, element.initializer ? ts.createAssignment(expression, element.initializer) : expression), element), element);
+            }
+            ts.Debug.assertNode(element.name, ts.isIdentifier);
+            return ts.setOriginalNode(ts.setTextRange(ts.createShorthandPropertyAssignment(element.name, element.initializer), element), element);
+        }
+        ts.Debug.assertNode(element, ts.isObjectLiteralElementLike);
+        return element;
+    }
+    ts.convertToObjectAssignmentElement = convertToObjectAssignmentElement;
+    function convertToAssignmentPattern(node) {
+        switch (node.kind) {
+            case 181 /* ArrayBindingPattern */:
+            case 183 /* ArrayLiteralExpression */:
+                return convertToArrayAssignmentPattern(node);
+            case 180 /* ObjectBindingPattern */:
+            case 184 /* ObjectLiteralExpression */:
+                return convertToObjectAssignmentPattern(node);
+        }
+    }
+    ts.convertToAssignmentPattern = convertToAssignmentPattern;
+    function convertToObjectAssignmentPattern(node) {
+        if (ts.isObjectBindingPattern(node)) {
+            return ts.setOriginalNode(ts.setTextRange(ts.createObjectLiteral(ts.map(node.elements, convertToObjectAssignmentElement)), node), node);
+        }
+        ts.Debug.assertNode(node, ts.isObjectLiteralExpression);
+        return node;
+    }
+    ts.convertToObjectAssignmentPattern = convertToObjectAssignmentPattern;
+    function convertToArrayAssignmentPattern(node) {
+        if (ts.isArrayBindingPattern(node)) {
+            return ts.setOriginalNode(ts.setTextRange(ts.createArrayLiteral(ts.map(node.elements, convertToArrayAssignmentElement)), node), node);
+        }
+        ts.Debug.assertNode(node, ts.isArrayLiteralExpression);
+        return node;
+    }
+    ts.convertToArrayAssignmentPattern = convertToArrayAssignmentPattern;
+    function convertToAssignmentElementTarget(node) {
+        if (ts.isBindingPattern(node)) {
+            return convertToAssignmentPattern(node);
+        }
+        ts.Debug.assertNode(node, ts.isExpression);
+        return node;
+    }
+    ts.convertToAssignmentElementTarget = convertToAssignmentElementTarget;
+})(ts || (ts = {}));
+var ts;
+(function (ts) {
+    var isTypeNodeOrTypeParameterDeclaration = ts.or(ts.isTypeNode, ts.isTypeParameterDeclaration);
+    function visitNode(node, visitor, test, lift) {
+        if (node === undefined || visitor === undefined) {
+            return node;
+        }
+        ts.aggregateTransformFlags(node);
+        var visited = visitor(node);
+        if (visited === node) {
+            return node;
+        }
+        var visitedNode;
+        if (visited === undefined) {
+            return undefined;
+        }
+        else if (ts.isArray(visited)) {
+            visitedNode = (lift || extractSingleNode)(visited);
+        }
+        else {
+            visitedNode = visited;
+        }
+        ts.Debug.assertNode(visitedNode, test);
+        ts.aggregateTransformFlags(visitedNode);
+        return visitedNode;
+    }
+    ts.visitNode = visitNode;
+    /**
+     * Visits a NodeArray using the supplied visitor, possibly returning a new NodeArray in its place.
+     *
+     * @param nodes The NodeArray to visit.
+     * @param visitor The callback used to visit a Node.
+     * @param test A node test to execute for each node.
+     * @param start An optional value indicating the starting offset at which to start visiting.
+     * @param count An optional value indicating the maximum number of nodes to visit.
+     */
+    function visitNodes(nodes, visitor, test, start, count) {
+        if (nodes === undefined || visitor === undefined) {
+            return nodes;
+        }
+        var updated;
+        // Ensure start and count have valid values
+        var length = nodes.length;
+        if (start === undefined || start < 0) {
+            start = 0;
+        }
+        if (count === undefined || count > length - start) {
+            count = length - start;
+        }
+        if (start > 0 || count < length) {
+            // If we are not visiting all of the original nodes, we must always create a new array.
+            // Since this is a fragment of a node array, we do not copy over the previous location
+            // and will only copy over `hasTrailingComma` if we are including the last element.
+            updated = ts.createNodeArray([], /*hasTrailingComma*/ nodes.hasTrailingComma && start + count === length);
+        }
+        // Visit each original node.
+        for (var i = 0; i < count; i++) {
+            var node = nodes[i + start];
+            ts.aggregateTransformFlags(node);
+            var visited = node !== undefined ? visitor(node) : undefined;
+            if (updated !== undefined || visited === undefined || visited !== node) {
+                if (updated === undefined) {
+                    // Ensure we have a copy of `nodes`, up to the current index.
+                    updated = ts.createNodeArray(nodes.slice(0, i), nodes.hasTrailingComma);
+                    ts.setTextRange(updated, nodes);
+                }
+                if (visited) {
+                    if (ts.isArray(visited)) {
+                        for (var _i = 0, visited_1 = visited; _i < visited_1.length; _i++) {
+                            var visitedNode = visited_1[_i];
+                            ts.Debug.assertNode(visitedNode, test);
+                            ts.aggregateTransformFlags(visitedNode);
+                            updated.push(visitedNode);
+                        }
+                    }
+                    else {
+                        ts.Debug.assertNode(visited, test);
+                        ts.aggregateTransformFlags(visited);
+                        updated.push(visited);
+                    }
+                }
+            }
+        }
+        return updated || nodes;
+    }
+    ts.visitNodes = visitNodes;
+    /**
+     * Starts a new lexical environment and visits a statement list, ending the lexical environment
+     * and merging hoisted declarations upon completion.
+     */
+    function visitLexicalEnvironment(statements, visitor, context, start, ensureUseStrict) {
+        context.startLexicalEnvironment();
+        statements = visitNodes(statements, visitor, ts.isStatement, start);
+        if (ensureUseStrict && !ts.startsWithUseStrict(statements)) {
+            statements = ts.setTextRange(ts.createNodeArray([ts.createStatement(ts.createLiteral("use strict"))].concat(statements)), statements);
+        }
+        var declarations = context.endLexicalEnvironment();
+        return ts.setTextRange(ts.createNodeArray(ts.concatenate(declarations, statements)), statements);
+    }
+    ts.visitLexicalEnvironment = visitLexicalEnvironment;
+    /**
+     * Starts a new lexical environment and visits a parameter list, suspending the lexical
+     * environment upon completion.
+     */
+    function visitParameterList(nodes, visitor, context, nodesVisitor) {
+        if (nodesVisitor === void 0) { nodesVisitor = visitNodes; }
+        context.startLexicalEnvironment();
+        var updated = nodesVisitor(nodes, visitor, ts.isParameterDeclaration);
+        context.suspendLexicalEnvironment();
+        return updated;
+    }
+    ts.visitParameterList = visitParameterList;
+    function visitFunctionBody(node, visitor, context) {
+        context.resumeLexicalEnvironment();
+        var updated = visitNode(node, visitor, ts.isConciseBody);
+        var declarations = context.endLexicalEnvironment();
+        if (ts.some(declarations)) {
+            var block = ts.convertToFunctionBody(updated);
+            var statements = ts.mergeLexicalEnvironment(block.statements, declarations);
+            return ts.updateBlock(block, statements);
+        }
+        return updated;
+    }
+    ts.visitFunctionBody = visitFunctionBody;
+    function visitEachChild(node, visitor, context, nodesVisitor, tokenVisitor) {
+        if (nodesVisitor === void 0) { nodesVisitor = visitNodes; }
+        if (node === undefined) {
+            return undefined;
+        }
+        var kind = node.kind;
+        // No need to visit nodes with no children.
+        if ((kind > 0 /* FirstToken */ && kind <= 145 /* LastToken */) || kind === 174 /* ThisType */) {
+            return node;
+        }
+        switch (kind) {
+            // Names
+            case 71 /* Identifier */:
+                return ts.updateIdentifier(node, nodesVisitor(node.typeArguments, visitor, isTypeNodeOrTypeParameterDeclaration));
+            case 146 /* QualifiedName */:
+                return ts.updateQualifiedName(node, visitNode(node.left, visitor, ts.isEntityName), visitNode(node.right, visitor, ts.isIdentifier));
+            case 147 /* ComputedPropertyName */:
+                return ts.updateComputedPropertyName(node, visitNode(node.expression, visitor, ts.isExpression));
+            // Signature elements
+            case 148 /* TypeParameter */:
+                return ts.updateTypeParameterDeclaration(node, visitNode(node.name, visitor, ts.isIdentifier), visitNode(node.constraint, visitor, ts.isTypeNode), visitNode(node.default, visitor, ts.isTypeNode));
+            case 149 /* Parameter */:
+                return ts.updateParameter(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.dotDotDotToken, tokenVisitor, ts.isToken), visitNode(node.name, visitor, ts.isBindingName), visitNode(node.questionToken, tokenVisitor, ts.isToken), visitNode(node.type, visitor, ts.isTypeNode), visitNode(node.initializer, visitor, ts.isExpression));
+            case 150 /* Decorator */:
+                return ts.updateDecorator(node, visitNode(node.expression, visitor, ts.isExpression));
+            // Type elements
+            case 151 /* PropertySignature */:
+                return ts.updatePropertySignature(node, nodesVisitor(node.modifiers, visitor, ts.isToken), visitNode(node.name, visitor, ts.isPropertyName), visitNode(node.questionToken, tokenVisitor, ts.isToken), visitNode(node.type, visitor, ts.isTypeNode), visitNode(node.initializer, visitor, ts.isExpression));
+            case 152 /* PropertyDeclaration */:
+                return ts.updateProperty(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.name, visitor, ts.isPropertyName), visitNode(node.questionToken, tokenVisitor, ts.isToken), visitNode(node.type, visitor, ts.isTypeNode), visitNode(node.initializer, visitor, ts.isExpression));
+            case 153 /* MethodSignature */:
+                return ts.updateMethodSignature(node, nodesVisitor(node.typeParameters, visitor, ts.isTypeParameterDeclaration), nodesVisitor(node.parameters, visitor, ts.isParameterDeclaration), visitNode(node.type, visitor, ts.isTypeNode), visitNode(node.name, visitor, ts.isPropertyName), visitNode(node.questionToken, tokenVisitor, ts.isToken));
+            case 154 /* MethodDeclaration */:
+                return ts.updateMethod(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.asteriskToken, tokenVisitor, ts.isToken), visitNode(node.name, visitor, ts.isPropertyName), visitNode(node.questionToken, tokenVisitor, ts.isToken), nodesVisitor(node.typeParameters, visitor, ts.isTypeParameterDeclaration), visitParameterList(node.parameters, visitor, context, nodesVisitor), visitNode(node.type, visitor, ts.isTypeNode), visitFunctionBody(node.body, visitor, context));
+            case 155 /* Constructor */:
+                return ts.updateConstructor(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitParameterList(node.parameters, visitor, context, nodesVisitor), visitFunctionBody(node.body, visitor, context));
+            case 156 /* GetAccessor */:
+                return ts.updateGetAccessor(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.name, visitor, ts.isPropertyName), visitParameterList(node.parameters, visitor, context, nodesVisitor), visitNode(node.type, visitor, ts.isTypeNode), visitFunctionBody(node.body, visitor, context));
+            case 157 /* SetAccessor */:
+                return ts.updateSetAccessor(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.name, visitor, ts.isPropertyName), visitParameterList(node.parameters, visitor, context, nodesVisitor), visitFunctionBody(node.body, visitor, context));
+            case 158 /* CallSignature */:
+                return ts.updateCallSignature(node, nodesVisitor(node.typeParameters, visitor, ts.isTypeParameterDeclaration), nodesVisitor(node.parameters, visitor, ts.isParameterDeclaration), visitNode(node.type, visitor, ts.isTypeNode));
+            case 159 /* ConstructSignature */:
+                return ts.updateConstructSignature(node, nodesVisitor(node.typeParameters, visitor, ts.isTypeParameterDeclaration), nodesVisitor(node.parameters, visitor, ts.isParameterDeclaration), visitNode(node.type, visitor, ts.isTypeNode));
+            case 160 /* IndexSignature */:
+                return ts.updateIndexSignature(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), nodesVisitor(node.parameters, visitor, ts.isParameterDeclaration), visitNode(node.type, visitor, ts.isTypeNode));
+            // Types
+            case 161 /* TypePredicate */:
+                return ts.updateTypePredicateNode(node, visitNode(node.parameterName, visitor), visitNode(node.type, visitor, ts.isTypeNode));
+            case 162 /* TypeReference */:
+                return ts.updateTypeReferenceNode(node, visitNode(node.typeName, visitor, ts.isEntityName), nodesVisitor(node.typeArguments, visitor, ts.isTypeNode));
+            case 163 /* FunctionType */:
+                return ts.updateFunctionTypeNode(node, nodesVisitor(node.typeParameters, visitor, ts.isTypeParameterDeclaration), nodesVisitor(node.parameters, visitor, ts.isParameterDeclaration), visitNode(node.type, visitor, ts.isTypeNode));
+            case 164 /* ConstructorType */:
+                return ts.updateConstructorTypeNode(node, nodesVisitor(node.typeParameters, visitor, ts.isTypeParameterDeclaration), nodesVisitor(node.parameters, visitor, ts.isParameterDeclaration), visitNode(node.type, visitor, ts.isTypeNode));
+            case 165 /* TypeQuery */:
+                return ts.updateTypeQueryNode(node, visitNode(node.exprName, visitor, ts.isEntityName));
+            case 166 /* TypeLiteral */:
+                return ts.updateTypeLiteralNode(node, nodesVisitor(node.members, visitor, ts.isTypeElement));
+            case 167 /* ArrayType */:
+                return ts.updateArrayTypeNode(node, visitNode(node.elementType, visitor, ts.isTypeNode));
+            case 168 /* TupleType */:
+                return ts.updateTypleTypeNode(node, nodesVisitor(node.elementTypes, visitor, ts.isTypeNode));
+            case 169 /* UnionType */:
+                return ts.updateUnionTypeNode(node, nodesVisitor(node.types, visitor, ts.isTypeNode));
+            case 170 /* IntersectionType */:
+                return ts.updateIntersectionTypeNode(node, nodesVisitor(node.types, visitor, ts.isTypeNode));
+            case 171 /* ConditionalType */:
+                return ts.updateConditionalTypeNode(node, visitNode(node.checkType, visitor, ts.isTypeNode), visitNode(node.extendsType, visitor, ts.isTypeNode), visitNode(node.trueType, visitor, ts.isTypeNode), visitNode(node.falseType, visitor, ts.isTypeNode));
+            case 172 /* InferType */:
+                return ts.updateInferTypeNode(node, visitNode(node.typeParameter, visitor, ts.isTypeParameterDeclaration));
+            case 179 /* ImportType */:
+                return ts.updateImportTypeNode(node, visitNode(node.argument, visitor, ts.isTypeNode), visitNode(node.qualifier, visitor, ts.isEntityName), visitNodes(node.typeArguments, visitor, ts.isTypeNode), node.isTypeOf);
+            case 173 /* ParenthesizedType */:
+                return ts.updateParenthesizedType(node, visitNode(node.type, visitor, ts.isTypeNode));
+            case 175 /* TypeOperator */:
+                return ts.updateTypeOperatorNode(node, visitNode(node.type, visitor, ts.isTypeNode));
+            case 176 /* IndexedAccessType */:
+                return ts.updateIndexedAccessTypeNode(node, visitNode(node.objectType, visitor, ts.isTypeNode), visitNode(node.indexType, visitor, ts.isTypeNode));
+            case 177 /* MappedType */:
+                return ts.updateMappedTypeNode(node, visitNode(node.readonlyToken, tokenVisitor, ts.isToken), visitNode(node.typeParameter, visitor, ts.isTypeParameterDeclaration), visitNode(node.questionToken, tokenVisitor, ts.isToken), visitNode(node.type, visitor, ts.isTypeNode));
+            case 178 /* LiteralType */:
+                return ts.updateLiteralTypeNode(node, visitNode(node.literal, visitor, ts.isExpression));
+            // Binding patterns
+            case 180 /* ObjectBindingPattern */:
+                return ts.updateObjectBindingPattern(node, nodesVisitor(node.elements, visitor, ts.isBindingElement));
+            case 181 /* ArrayBindingPattern */:
+                return ts.updateArrayBindingPattern(node, nodesVisitor(node.elements, visitor, ts.isArrayBindingElement));
+            case 182 /* BindingElement */:
+                return ts.updateBindingElement(node, visitNode(node.dotDotDotToken, tokenVisitor, ts.isToken), visitNode(node.propertyName, visitor, ts.isPropertyName), visitNode(node.name, visitor, ts.isBindingName), visitNode(node.initializer, visitor, ts.isExpression));
+            // Expression
+            case 183 /* ArrayLiteralExpression */:
+                return ts.updateArrayLiteral(node, nodesVisitor(node.elements, visitor, ts.isExpression));
+            case 184 /* ObjectLiteralExpression */:
+                return ts.updateObjectLiteral(node, nodesVisitor(node.properties, visitor, ts.isObjectLiteralElementLike));
+            case 185 /* PropertyAccessExpression */:
+                return ts.updatePropertyAccess(node, visitNode(node.expression, visitor, ts.isExpression), visitNode(node.name, visitor, ts.isIdentifier));
+            case 186 /* ElementAccessExpression */:
+                return ts.updateElementAccess(node, visitNode(node.expression, visitor, ts.isExpression), visitNode(node.argumentExpression, visitor, ts.isExpression));
+            case 187 /* CallExpression */:
+                return ts.updateCall(node, visitNode(node.expression, visitor, ts.isExpression), nodesVisitor(node.typeArguments, visitor, ts.isTypeNode), nodesVisitor(node.arguments, visitor, ts.isExpression));
+            case 188 /* NewExpression */:
+                return ts.updateNew(node, visitNode(node.expression, visitor, ts.isExpression), nodesVisitor(node.typeArguments, visitor, ts.isTypeNode), nodesVisitor(node.arguments, visitor, ts.isExpression));
+            case 189 /* TaggedTemplateExpression */:
+                return ts.updateTaggedTemplate(node, visitNode(node.tag, visitor, ts.isExpression), visitNodes(node.typeArguments, visitor, ts.isExpression), visitNode(node.template, visitor, ts.isTemplateLiteral));
+            case 190 /* TypeAssertionExpression */:
+                return ts.updateTypeAssertion(node, visitNode(node.type, visitor, ts.isTypeNode), visitNode(node.expression, visitor, ts.isExpression));
+            case 191 /* ParenthesizedExpression */:
+                return ts.updateParen(node, visitNode(node.expression, visitor, ts.isExpression));
+            case 192 /* FunctionExpression */:
+                return ts.updateFunctionExpression(node, nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.asteriskToken, tokenVisitor, ts.isToken), visitNode(node.name, visitor, ts.isIdentifier), nodesVisitor(node.typeParameters, visitor, ts.isTypeParameterDeclaration), visitParameterList(node.parameters, visitor, context, nodesVisitor), visitNode(node.type, visitor, ts.isTypeNode), visitFunctionBody(node.body, visitor, context));
+            case 193 /* ArrowFunction */:
+                return ts.updateArrowFunction(node, nodesVisitor(node.modifiers, visitor, ts.isModifier), nodesVisitor(node.typeParameters, visitor, ts.isTypeParameterDeclaration), visitParameterList(node.parameters, visitor, context, nodesVisitor), visitNode(node.type, visitor, ts.isTypeNode), visitNode(node.equalsGreaterThanToken, visitor, ts.isToken), visitFunctionBody(node.body, visitor, context));
+            case 194 /* DeleteExpression */:
+                return ts.updateDelete(node, visitNode(node.expression, visitor, ts.isExpression));
+            case 195 /* TypeOfExpression */:
+                return ts.updateTypeOf(node, visitNode(node.expression, visitor, ts.isExpression));
+            case 196 /* VoidExpression */:
+                return ts.updateVoid(node, visitNode(node.expression, visitor, ts.isExpression));
+            case 197 /* AwaitExpression */:
+                return ts.updateAwait(node, visitNode(node.expression, visitor, ts.isExpression));
+            case 198 /* PrefixUnaryExpression */:
+                return ts.updatePrefix(node, visitNode(node.operand, visitor, ts.isExpression));
+            case 199 /* PostfixUnaryExpression */:
+                return ts.updatePostfix(node, visitNode(node.operand, visitor, ts.isExpression));
+            case 200 /* BinaryExpression */:
+                return ts.updateBinary(node, visitNode(node.left, visitor, ts.isExpression), visitNode(node.right, visitor, ts.isExpression), visitNode(node.operatorToken, visitor, ts.isToken));
+            case 201 /* ConditionalExpression */:
+                return ts.updateConditional(node, visitNode(node.condition, visitor, ts.isExpression), visitNode(node.questionToken, visitor, ts.isToken), visitNode(node.whenTrue, visitor, ts.isExpression), visitNode(node.colonToken, visitor, ts.isToken), visitNode(node.whenFalse, visitor, ts.isExpression));
+            case 202 /* TemplateExpression */:
+                return ts.updateTemplateExpression(node, visitNode(node.head, visitor, ts.isTemplateHead), nodesVisitor(node.templateSpans, visitor, ts.isTemplateSpan));
+            case 203 /* YieldExpression */:
+                return ts.updateYield(node, visitNode(node.asteriskToken, tokenVisitor, ts.isToken), visitNode(node.expression, visitor, ts.isExpression));
+            case 204 /* SpreadElement */:
+                return ts.updateSpread(node, visitNode(node.expression, visitor, ts.isExpression));
+            case 205 /* ClassExpression */:
+                return ts.updateClassExpression(node, nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.name, visitor, ts.isIdentifier), nodesVisitor(node.typeParameters, visitor, ts.isTypeParameterDeclaration), nodesVisitor(node.heritageClauses, visitor, ts.isHeritageClause), nodesVisitor(node.members, visitor, ts.isClassElement));
+            case 207 /* ExpressionWithTypeArguments */:
+                return ts.updateExpressionWithTypeArguments(node, nodesVisitor(node.typeArguments, visitor, ts.isTypeNode), visitNode(node.expression, visitor, ts.isExpression));
+            case 208 /* AsExpression */:
+                return ts.updateAsExpression(node, visitNode(node.expression, visitor, ts.isExpression), visitNode(node.type, visitor, ts.isTypeNode));
+            case 209 /* NonNullExpression */:
+                return ts.updateNonNullExpression(node, visitNode(node.expression, visitor, ts.isExpression));
+            case 210 /* MetaProperty */:
+                return ts.updateMetaProperty(node, visitNode(node.name, visitor, ts.isIdentifier));
+            // Misc
+            case 211 /* TemplateSpan */:
+                return ts.updateTemplateSpan(node, visitNode(node.expression, visitor, ts.isExpression), visitNode(node.literal, visitor, ts.isTemplateMiddleOrTemplateTail));
+            // Element
+            case 213 /* Block */:
+                return ts.updateBlock(node, nodesVisitor(node.statements, visitor, ts.isStatement));
+            case 214 /* VariableStatement */:
+                return ts.updateVariableStatement(node, nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.declarationList, visitor, ts.isVariableDeclarationList));
+            case 216 /* ExpressionStatement */:
+                return ts.updateStatement(node, visitNode(node.expression, visitor, ts.isExpression));
+            case 217 /* IfStatement */:
+                return ts.updateIf(node, visitNode(node.expression, visitor, ts.isExpression), visitNode(node.thenStatement, visitor, ts.isStatement, ts.liftToBlock), visitNode(node.elseStatement, visitor, ts.isStatement, ts.liftToBlock));
+            case 218 /* DoStatement */:
+                return ts.updateDo(node, visitNode(node.statement, visitor, ts.isStatement, ts.liftToBlock), visitNode(node.expression, visitor, ts.isExpression));
+            case 219 /* WhileStatement */:
+                return ts.updateWhile(node, visitNode(node.expression, visitor, ts.isExpression), visitNode(node.statement, visitor, ts.isStatement, ts.liftToBlock));
+            case 220 /* ForStatement */:
+                return ts.updateFor(node, visitNode(node.initializer, visitor, ts.isForInitializer), visitNode(node.condition, visitor, ts.isExpression), visitNode(node.incrementor, visitor, ts.isExpression), visitNode(node.statement, visitor, ts.isStatement, ts.liftToBlock));
+            case 221 /* ForInStatement */:
+                return ts.updateForIn(node, visitNode(node.initializer, visitor, ts.isForInitializer), visitNode(node.expression, visitor, ts.isExpression), visitNode(node.statement, visitor, ts.isStatement, ts.liftToBlock));
+            case 222 /* ForOfStatement */:
+                return ts.updateForOf(node, visitNode(node.awaitModifier, visitor, ts.isToken), visitNode(node.initializer, visitor, ts.isForInitializer), visitNode(node.expression, visitor, ts.isExpression), visitNode(node.statement, visitor, ts.isStatement, ts.liftToBlock));
+            case 223 /* ContinueStatement */:
+                return ts.updateContinue(node, visitNode(node.label, visitor, ts.isIdentifier));
+            case 224 /* BreakStatement */:
+                return ts.updateBreak(node, visitNode(node.label, visitor, ts.isIdentifier));
+            case 225 /* ReturnStatement */:
+                return ts.updateReturn(node, visitNode(node.expression, visitor, ts.isExpression));
+            case 226 /* WithStatement */:
+                return ts.updateWith(node, visitNode(node.expression, visitor, ts.isExpression), visitNode(node.statement, visitor, ts.isStatement, ts.liftToBlock));
+            case 227 /* SwitchStatement */:
+                return ts.updateSwitch(node, visitNode(node.expression, visitor, ts.isExpression), visitNode(node.caseBlock, visitor, ts.isCaseBlock));
+            case 228 /* LabeledStatement */:
+                return ts.updateLabel(node, visitNode(node.label, visitor, ts.isIdentifier), visitNode(node.statement, visitor, ts.isStatement, ts.liftToBlock));
+            case 229 /* ThrowStatement */:
+                return ts.updateThrow(node, visitNode(node.expression, visitor, ts.isExpression));
+            case 230 /* TryStatement */:
+                return ts.updateTry(node, visitNode(node.tryBlock, visitor, ts.isBlock), visitNode(node.catchClause, visitor, ts.isCatchClause), visitNode(node.finallyBlock, visitor, ts.isBlock));
+            case 232 /* VariableDeclaration */:
+                return ts.updateVariableDeclaration(node, visitNode(node.name, visitor, ts.isBindingName), visitNode(node.type, visitor, ts.isTypeNode), visitNode(node.initializer, visitor, ts.isExpression));
+            case 233 /* VariableDeclarationList */:
+                return ts.updateVariableDeclarationList(node, nodesVisitor(node.declarations, visitor, ts.isVariableDeclaration));
+            case 234 /* FunctionDeclaration */:
+                return ts.updateFunctionDeclaration(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.asteriskToken, tokenVisitor, ts.isToken), visitNode(node.name, visitor, ts.isIdentifier), nodesVisitor(node.typeParameters, visitor, ts.isTypeParameterDeclaration), visitParameterList(node.parameters, visitor, context, nodesVisitor), visitNode(node.type, visitor, ts.isTypeNode), visitFunctionBody(node.body, visitor, context));
+            case 235 /* ClassDeclaration */:
+                return ts.updateClassDeclaration(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.name, visitor, ts.isIdentifier), nodesVisitor(node.typeParameters, visitor, ts.isTypeParameterDeclaration), nodesVisitor(node.heritageClauses, visitor, ts.isHeritageClause), nodesVisitor(node.members, visitor, ts.isClassElement));
+            case 236 /* InterfaceDeclaration */:
+                return ts.updateInterfaceDeclaration(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.name, visitor, ts.isIdentifier), nodesVisitor(node.typeParameters, visitor, ts.isTypeParameterDeclaration), nodesVisitor(node.heritageClauses, visitor, ts.isHeritageClause), nodesVisitor(node.members, visitor, ts.isTypeElement));
+            case 237 /* TypeAliasDeclaration */:
+                return ts.updateTypeAliasDeclaration(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.name, visitor, ts.isIdentifier), nodesVisitor(node.typeParameters, visitor, ts.isTypeParameterDeclaration), visitNode(node.type, visitor, ts.isTypeNode));
+            case 238 /* EnumDeclaration */:
+                return ts.updateEnumDeclaration(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.name, visitor, ts.isIdentifier), nodesVisitor(node.members, visitor, ts.isEnumMember));
+            case 239 /* ModuleDeclaration */:
+                return ts.updateModuleDeclaration(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.name, visitor, ts.isIdentifier), visitNode(node.body, visitor, ts.isModuleBody));
+            case 240 /* ModuleBlock */:
+                return ts.updateModuleBlock(node, nodesVisitor(node.statements, visitor, ts.isStatement));
+            case 241 /* CaseBlock */:
+                return ts.updateCaseBlock(node, nodesVisitor(node.clauses, visitor, ts.isCaseOrDefaultClause));
+            case 242 /* NamespaceExportDeclaration */:
+                return ts.updateNamespaceExportDeclaration(node, visitNode(node.name, visitor, ts.isIdentifier));
+            case 243 /* ImportEqualsDeclaration */:
+                return ts.updateImportEqualsDeclaration(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.name, visitor, ts.isIdentifier), visitNode(node.moduleReference, visitor, ts.isModuleReference));
+            case 244 /* ImportDeclaration */:
+                return ts.updateImportDeclaration(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.importClause, visitor, ts.isImportClause), visitNode(node.moduleSpecifier, visitor, ts.isExpression));
+            case 245 /* ImportClause */:
+                return ts.updateImportClause(node, visitNode(node.name, visitor, ts.isIdentifier), visitNode(node.namedBindings, visitor, ts.isNamedImportBindings));
+            case 246 /* NamespaceImport */:
+                return ts.updateNamespaceImport(node, visitNode(node.name, visitor, ts.isIdentifier));
+            case 247 /* NamedImports */:
+                return ts.updateNamedImports(node, nodesVisitor(node.elements, visitor, ts.isImportSpecifier));
+            case 248 /* ImportSpecifier */:
+                return ts.updateImportSpecifier(node, visitNode(node.propertyName, visitor, ts.isIdentifier), visitNode(node.name, visitor, ts.isIdentifier));
+            case 249 /* ExportAssignment */:
+                return ts.updateExportAssignment(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.expression, visitor, ts.isExpression));
+            case 250 /* ExportDeclaration */:
+                return ts.updateExportDeclaration(node, nodesVisitor(node.decorators, visitor, ts.isDecorator), nodesVisitor(node.modifiers, visitor, ts.isModifier), visitNode(node.exportClause, visitor, ts.isNamedExports), visitNode(node.moduleSpecifier, visitor, ts.isExpression));
+            case 251 /* NamedExports */:
+                return ts.updateNamedExports(node, nodesVisitor(node.elements, visitor, ts.isExportSpecifier));
+            case 252 /* ExportSpecifier */:
+                return ts.updateExportSpecifier(node, visitNode(node.propertyName, visitor, ts.isIdentifier), visitNode(node.name, visitor, ts.isIdentifier));
+            // Module references
+            case 254 /* ExternalModuleReference */:
+                return ts.updateExternalModuleReference(node, visitNode(node.expression, visitor, ts.isExpression));
+            // JSX
+            case 255 /* JsxElement */:
+                return ts.updateJsxElement(node, visitNode(node.openingElement, visitor, ts.isJsxOpeningElement), nodesVisitor(node.children, visitor, ts.isJsxChild), visitNode(node.closingElement, visitor, ts.isJsxClosingElement));
+            case 256 /* JsxSelfClosingElement */:
+                return ts.updateJsxSelfClosingElement(node, visitNode(node.tagName, visitor, ts.isJsxTagNameExpression), nodesVisitor(node.typeArguments, visitor, ts.isTypeNode), visitNode(node.attributes, visitor, ts.isJsxAttributes));
+            case 257 /* JsxOpeningElement */:
+                return ts.updateJsxOpeningElement(node, visitNode(node.tagName, visitor, ts.isJsxTagNameExpression), nodesVisitor(node.typeArguments, visitor, ts.isTypeNode), visitNode(node.attributes, visitor, ts.isJsxAttributes));
+            case 258 /* JsxClosingElement */:
+                return ts.updateJsxClosingElement(node, visitNode(node.tagName, visitor, ts.isJsxTagNameExpression));
+            case 259 /* JsxFragment */:
+                return ts.updateJsxFragment(node, visitNode(node.openingFragment, visitor, ts.isJsxOpeningFragment), nodesVisitor(node.children, visitor, ts.isJsxChild), visitNode(node.closingFragment, visitor, ts.isJsxClosingFragment));
+            case 262 /* JsxAttribute */:
+                return ts.updateJsxAttribute(node, visitNode(node.name, visitor, ts.isIdentifier), visitNode(node.initializer, visitor, ts.isStringLiteralOrJsxExpression));
+            case 263 /* JsxAttributes */:
+                return ts.updateJsxAttributes(node, nodesVisitor(node.properties, visitor, ts.isJsxAttributeLike));
+            case 264 /* JsxSpreadAttribute */:
+                return ts.updateJsxSpreadAttribute(node, visitNode(node.expression, visitor, ts.isExpression));
+            case 265 /* JsxExpression */:
+                return ts.updateJsxExpression(node, visitNode(node.expression, visitor, ts.isExpression));
+            // Clauses
+            case 266 /* CaseClause */:
+                return ts.updateCaseClause(node, visitNode(node.expression, visitor, ts.isExpression), nodesVisitor(node.statements, visitor, ts.isStatement));
+            case 267 /* DefaultClause */:
+                return ts.updateDefaultClause(node, nodesVisitor(node.statements, visitor, ts.isStatement));
+            case 268 /* HeritageClause */:
+                return ts.updateHeritageClause(node, nodesVisitor(node.types, visitor, ts.isExpressionWithTypeArguments));
+            case 269 /* CatchClause */:
+                return ts.updateCatchClause(node, visitNode(node.variableDeclaration, visitor, ts.isVariableDeclaration), visitNode(node.block, visitor, ts.isBlock));
+            // Property assignments
+            case 270 /* PropertyAssignment */:
+                return ts.updatePropertyAssignment(node, visitNode(node.name, visitor, ts.isPropertyName), visitNode(node.initializer, visitor, ts.isExpression));
+            case 271 /* ShorthandPropertyAssignment */:
+                return ts.updateShorthandPropertyAssignment(node, visitNode(node.name, visitor, ts.isIdentifier), visitNode(node.objectAssignmentInitializer, visitor, ts.isExpression));
+            case 272 /* SpreadAssignment */:
+                return ts.updateSpreadAssignment(node, visitNode(node.expression, visitor, ts.isExpression));
+            // Enum
+            case 273 /* EnumMember */:
+                return ts.updateEnumMember(node, visitNode(node.name, visitor, ts.isPropertyName), visitNode(node.initializer, visitor, ts.isExpression));
+            // Top-level nodes
+            case 274 /* SourceFile */:
+                return ts.updateSourceFileNode(node, visitLexicalEnvironment(node.statements, visitor, context));
+            // Transformation nodes
+            case 301 /* PartiallyEmittedExpression */:
+                return ts.updatePartiallyEmittedExpression(node, visitNode(node.expression, visitor, ts.isExpression));
+            case 302 /* CommaListExpression */:
+                return ts.updateCommaList(node, nodesVisitor(node.elements, visitor, ts.isExpression));
+            default:
+                // No need to visit nodes with no children.
+                return node;
+        }
+    }
+    ts.visitEachChild = visitEachChild;
+    /**
+     * Extracts the single node from a NodeArray.
+     *
+     * @param nodes The NodeArray.
+     */
+    function extractSingleNode(nodes) {
+        ts.Debug.assert(nodes.length <= 1, "Too many nodes written to output.");
+        return ts.singleOrUndefined(nodes);
+    }
+})(ts || (ts = {}));
+/* @internal */
+(function (ts) {
+    function reduceNode(node, f, initial) {
+        return node ? f(initial, node) : initial;
+    }
+    function reduceNodeArray(nodes, f, initial) {
+        return nodes ? f(initial, nodes) : initial;
+    }
+    /**
+     * Similar to `reduceLeft`, performs a reduction against each child of a node.
+     * NOTE: Unlike `forEachChild`, this does *not* visit every node.
+     *
+     * @param node The node containing the children to reduce.
+     * @param initial The initial value to supply to the reduction.
+     * @param f The callback function
+     */
+    function reduceEachChild(node, initial, cbNode, cbNodeArray) {
+        if (node === undefined) {
+            return initial;
+        }
+        var reduceNodes = cbNodeArray ? reduceNodeArray : ts.reduceLeft;
+        var cbNodes = cbNodeArray || cbNode;
+        var kind = node.kind;
+        // No need to visit nodes with no children.
+        if ((kind > 0 /* FirstToken */ && kind <= 145 /* LastToken */)) {
+            return initial;
+        }
+        // We do not yet support types.
+        if ((kind >= 161 /* TypePredicate */ && kind <= 178 /* LiteralType */)) {
+            return initial;
+        }
+        var result = initial;
+        switch (node.kind) {
+            // Leaf nodes
+            case 212 /* SemicolonClassElement */:
+            case 215 /* EmptyStatement */:
+            case 206 /* OmittedExpression */:
+            case 231 /* DebuggerStatement */:
+            case 300 /* NotEmittedStatement */:
+                // No need to visit nodes with no children.
+                break;
+            // Names
+            case 146 /* QualifiedName */:
+                result = reduceNode(node.left, cbNode, result);
+                result = reduceNode(node.right, cbNode, result);
+                break;
+            case 147 /* ComputedPropertyName */:
+                result = reduceNode(node.expression, cbNode, result);
+                break;
+            // Signature elements
+            case 149 /* Parameter */:
+                result = reduceNodes(node.decorators, cbNodes, result);
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNode(node.type, cbNode, result);
+                result = reduceNode(node.initializer, cbNode, result);
+                break;
+            case 150 /* Decorator */:
+                result = reduceNode(node.expression, cbNode, result);
+                break;
+            // Type member
+            case 151 /* PropertySignature */:
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNode(node.questionToken, cbNode, result);
+                result = reduceNode(node.type, cbNode, result);
+                result = reduceNode(node.initializer, cbNode, result);
+                break;
+            case 152 /* PropertyDeclaration */:
+                result = reduceNodes(node.decorators, cbNodes, result);
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNode(node.type, cbNode, result);
+                result = reduceNode(node.initializer, cbNode, result);
+                break;
+            case 154 /* MethodDeclaration */:
+                result = reduceNodes(node.decorators, cbNodes, result);
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNodes(node.typeParameters, cbNodes, result);
+                result = reduceNodes(node.parameters, cbNodes, result);
+                result = reduceNode(node.type, cbNode, result);
+                result = reduceNode(node.body, cbNode, result);
+                break;
+            case 155 /* Constructor */:
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNodes(node.parameters, cbNodes, result);
+                result = reduceNode(node.body, cbNode, result);
+                break;
+            case 156 /* GetAccessor */:
+                result = reduceNodes(node.decorators, cbNodes, result);
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNodes(node.parameters, cbNodes, result);
+                result = reduceNode(node.type, cbNode, result);
+                result = reduceNode(node.body, cbNode, result);
+                break;
+            case 157 /* SetAccessor */:
+                result = reduceNodes(node.decorators, cbNodes, result);
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNodes(node.parameters, cbNodes, result);
+                result = reduceNode(node.body, cbNode, result);
+                break;
+            // Binding patterns
+            case 180 /* ObjectBindingPattern */:
+            case 181 /* ArrayBindingPattern */:
+                result = reduceNodes(node.elements, cbNodes, result);
+                break;
+            case 182 /* BindingElement */:
+                result = reduceNode(node.propertyName, cbNode, result);
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNode(node.initializer, cbNode, result);
+                break;
+            // Expression
+            case 183 /* ArrayLiteralExpression */:
+                result = reduceNodes(node.elements, cbNodes, result);
+                break;
+            case 184 /* ObjectLiteralExpression */:
+                result = reduceNodes(node.properties, cbNodes, result);
+                break;
+            case 185 /* PropertyAccessExpression */:
+                result = reduceNode(node.expression, cbNode, result);
+                result = reduceNode(node.name, cbNode, result);
+                break;
+            case 186 /* ElementAccessExpression */:
+                result = reduceNode(node.expression, cbNode, result);
+                result = reduceNode(node.argumentExpression, cbNode, result);
+                break;
+            case 187 /* CallExpression */:
+                result = reduceNode(node.expression, cbNode, result);
+                result = reduceNodes(node.typeArguments, cbNodes, result);
+                result = reduceNodes(node.arguments, cbNodes, result);
+                break;
+            case 188 /* NewExpression */:
+                result = reduceNode(node.expression, cbNode, result);
+                result = reduceNodes(node.typeArguments, cbNodes, result);
+                result = reduceNodes(node.arguments, cbNodes, result);
+                break;
+            case 189 /* TaggedTemplateExpression */:
+                result = reduceNode(node.tag, cbNode, result);
+                result = reduceNode(node.template, cbNode, result);
+                break;
+            case 190 /* TypeAssertionExpression */:
+                result = reduceNode(node.type, cbNode, result);
+                result = reduceNode(node.expression, cbNode, result);
+                break;
+            case 192 /* FunctionExpression */:
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNodes(node.typeParameters, cbNodes, result);
+                result = reduceNodes(node.parameters, cbNodes, result);
+                result = reduceNode(node.type, cbNode, result);
+                result = reduceNode(node.body, cbNode, result);
+                break;
+            case 193 /* ArrowFunction */:
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNodes(node.typeParameters, cbNodes, result);
+                result = reduceNodes(node.parameters, cbNodes, result);
+                result = reduceNode(node.type, cbNode, result);
+                result = reduceNode(node.body, cbNode, result);
+                break;
+            case 191 /* ParenthesizedExpression */:
+            case 194 /* DeleteExpression */:
+            case 195 /* TypeOfExpression */:
+            case 196 /* VoidExpression */:
+            case 197 /* AwaitExpression */:
+            case 203 /* YieldExpression */:
+            case 204 /* SpreadElement */:
+            case 209 /* NonNullExpression */:
+                result = reduceNode(node.expression, cbNode, result);
+                break;
+            case 198 /* PrefixUnaryExpression */:
+            case 199 /* PostfixUnaryExpression */:
+                result = reduceNode(node.operand, cbNode, result);
+                break;
+            case 200 /* BinaryExpression */:
+                result = reduceNode(node.left, cbNode, result);
+                result = reduceNode(node.right, cbNode, result);
+                break;
+            case 201 /* ConditionalExpression */:
+                result = reduceNode(node.condition, cbNode, result);
+                result = reduceNode(node.whenTrue, cbNode, result);
+                result = reduceNode(node.whenFalse, cbNode, result);
+                break;
+            case 202 /* TemplateExpression */:
+                result = reduceNode(node.head, cbNode, result);
+                result = reduceNodes(node.templateSpans, cbNodes, result);
+                break;
+            case 205 /* ClassExpression */:
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNodes(node.typeParameters, cbNodes, result);
+                result = reduceNodes(node.heritageClauses, cbNodes, result);
+                result = reduceNodes(node.members, cbNodes, result);
+                break;
+            case 207 /* ExpressionWithTypeArguments */:
+                result = reduceNode(node.expression, cbNode, result);
+                result = reduceNodes(node.typeArguments, cbNodes, result);
+                break;
+            case 208 /* AsExpression */:
+                result = reduceNode(node.expression, cbNode, result);
+                result = reduceNode(node.type, cbNode, result);
+                break;
+            // Misc
+            case 211 /* TemplateSpan */:
+                result = reduceNode(node.expression, cbNode, result);
+                result = reduceNode(node.literal, cbNode, result);
+                break;
+            // Element
+            case 213 /* Block */:
+                result = reduceNodes(node.statements, cbNodes, result);
+                break;
+            case 214 /* VariableStatement */:
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.declarationList, cbNode, result);
+                break;
+            case 216 /* ExpressionStatement */:
+                result = reduceNode(node.expression, cbNode, result);
+                break;
+            case 217 /* IfStatement */:
+                result = reduceNode(node.expression, cbNode, result);
+                result = reduceNode(node.thenStatement, cbNode, result);
+                result = reduceNode(node.elseStatement, cbNode, result);
+                break;
+            case 218 /* DoStatement */:
+                result = reduceNode(node.statement, cbNode, result);
+                result = reduceNode(node.expression, cbNode, result);
+                break;
+            case 219 /* WhileStatement */:
+            case 226 /* WithStatement */:
+                result = reduceNode(node.expression, cbNode, result);
+                result = reduceNode(node.statement, cbNode, result);
+                break;
+            case 220 /* ForStatement */:
+                result = reduceNode(node.initializer, cbNode, result);
+                result = reduceNode(node.condition, cbNode, result);
+                result = reduceNode(node.incrementor, cbNode, result);
+                result = reduceNode(node.statement, cbNode, result);
+                break;
+            case 221 /* ForInStatement */:
+            case 222 /* ForOfStatement */:
+                result = reduceNode(node.initializer, cbNode, result);
+                result = reduceNode(node.expression, cbNode, result);
+                result = reduceNode(node.statement, cbNode, result);
+                break;
+            case 225 /* ReturnStatement */:
+            case 229 /* ThrowStatement */:
+                result = reduceNode(node.expression, cbNode, result);
+                break;
+            case 227 /* SwitchStatement */:
+                result = reduceNode(node.expression, cbNode, result);
+                result = reduceNode(node.caseBlock, cbNode, result);
+                break;
+            case 228 /* LabeledStatement */:
+                result = reduceNode(node.label, cbNode, result);
+                result = reduceNode(node.statement, cbNode, result);
+                break;
+            case 230 /* TryStatement */:
+                result = reduceNode(node.tryBlock, cbNode, result);
+                result = reduceNode(node.catchClause, cbNode, result);
+                result = reduceNode(node.finallyBlock, cbNode, result);
+                break;
+            case 232 /* VariableDeclaration */:
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNode(node.type, cbNode, result);
+                result = reduceNode(node.initializer, cbNode, result);
+                break;
+            case 233 /* VariableDeclarationList */:
+                result = reduceNodes(node.declarations, cbNodes, result);
+                break;
+            case 234 /* FunctionDeclaration */:
+                result = reduceNodes(node.decorators, cbNodes, result);
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNodes(node.typeParameters, cbNodes, result);
+                result = reduceNodes(node.parameters, cbNodes, result);
+                result = reduceNode(node.type, cbNode, result);
+                result = reduceNode(node.body, cbNode, result);
+                break;
+            case 235 /* ClassDeclaration */:
+                result = reduceNodes(node.decorators, cbNodes, result);
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNodes(node.typeParameters, cbNodes, result);
+                result = reduceNodes(node.heritageClauses, cbNodes, result);
+                result = reduceNodes(node.members, cbNodes, result);
+                break;
+            case 238 /* EnumDeclaration */:
+                result = reduceNodes(node.decorators, cbNodes, result);
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNodes(node.members, cbNodes, result);
+                break;
+            case 239 /* ModuleDeclaration */:
+                result = reduceNodes(node.decorators, cbNodes, result);
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNode(node.body, cbNode, result);
+                break;
+            case 240 /* ModuleBlock */:
+                result = reduceNodes(node.statements, cbNodes, result);
+                break;
+            case 241 /* CaseBlock */:
+                result = reduceNodes(node.clauses, cbNodes, result);
+                break;
+            case 243 /* ImportEqualsDeclaration */:
+                result = reduceNodes(node.decorators, cbNodes, result);
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNode(node.moduleReference, cbNode, result);
+                break;
+            case 244 /* ImportDeclaration */:
+                result = reduceNodes(node.decorators, cbNodes, result);
+                result = reduceNodes(node.modifiers, cbNodes, result);
+                result = reduceNode(node.importClause, cbNode, result);
+                result = reduceNode(node.moduleSpecifier, cbNode, result);
+                break;
+            case 245 /* ImportClause */:
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNode(node.namedBindings, cbNode, result);
+                break;
+            case 246 /* NamespaceImport */:
+                result = reduceNode(node.name, cbNode, result);
+                break;
+            case 247 /* NamedImports */:
+            case 251 /* NamedExports */:
+                result = reduceNodes(node.elements, cbNodes, result);
+                break;
+            case 248 /* ImportSpecifier */:
+            case 252 /* ExportSpecifier */:
+                result = reduceNode(node.propertyName, cbNode, result);
+                result = reduceNode(node.name, cbNode, result);
+                break;
+            case 249 /* ExportAssignment */:
+                result = ts.reduceLeft(node.decorators, cbNode, result);
+                result = ts.reduceLeft(node.modifiers, cbNode, result);
+                result = reduceNode(node.expression, cbNode, result);
+                break;
+            case 250 /* ExportDeclaration */:
+                result = ts.reduceLeft(node.decorators, cbNode, result);
+                result = ts.reduceLeft(node.modifiers, cbNode, result);
+                result = reduceNode(node.exportClause, cbNode, result);
+                result = reduceNode(node.moduleSpecifier, cbNode, result);
+                break;
+            // Module references
+            case 254 /* ExternalModuleReference */:
+                result = reduceNode(node.expression, cbNode, result);
+                break;
+            // JSX
+            case 255 /* JsxElement */:
+                result = reduceNode(node.openingElement, cbNode, result);
+                result = ts.reduceLeft(node.children, cbNode, result);
+                result = reduceNode(node.closingElement, cbNode, result);
+                break;
+            case 259 /* JsxFragment */:
+                result = reduceNode(node.openingFragment, cbNode, result);
+                result = ts.reduceLeft(node.children, cbNode, result);
+                result = reduceNode(node.closingFragment, cbNode, result);
+                break;
+            case 256 /* JsxSelfClosingElement */:
+            case 257 /* JsxOpeningElement */:
+                result = reduceNode(node.tagName, cbNode, result);
+                result = reduceNode(node.attributes, cbNode, result);
+                break;
+            case 263 /* JsxAttributes */:
+                result = reduceNodes(node.properties, cbNodes, result);
+                break;
+            case 258 /* JsxClosingElement */:
+                result = reduceNode(node.tagName, cbNode, result);
+                break;
+            case 262 /* JsxAttribute */:
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNode(node.initializer, cbNode, result);
+                break;
+            case 264 /* JsxSpreadAttribute */:
+                result = reduceNode(node.expression, cbNode, result);
+                break;
+            case 265 /* JsxExpression */:
+                result = reduceNode(node.expression, cbNode, result);
+                break;
+            // Clauses
+            case 266 /* CaseClause */:
+                result = reduceNode(node.expression, cbNode, result);
+            // falls through
+            case 267 /* DefaultClause */:
+                result = reduceNodes(node.statements, cbNodes, result);
+                break;
+            case 268 /* HeritageClause */:
+                result = reduceNodes(node.types, cbNodes, result);
+                break;
+            case 269 /* CatchClause */:
+                result = reduceNode(node.variableDeclaration, cbNode, result);
+                result = reduceNode(node.block, cbNode, result);
+                break;
+            // Property assignments
+            case 270 /* PropertyAssignment */:
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNode(node.initializer, cbNode, result);
+                break;
+            case 271 /* ShorthandPropertyAssignment */:
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNode(node.objectAssignmentInitializer, cbNode, result);
+                break;
+            case 272 /* SpreadAssignment */:
+                result = reduceNode(node.expression, cbNode, result);
+                break;
+            // Enum
+            case 273 /* EnumMember */:
+                result = reduceNode(node.name, cbNode, result);
+                result = reduceNode(node.initializer, cbNode, result);
+                break;
+            // Top-level nodes
+            case 274 /* SourceFile */:
+                result = reduceNodes(node.statements, cbNodes, result);
+                break;
+            // Transformation nodes
+            case 301 /* PartiallyEmittedExpression */:
+                result = reduceNode(node.expression, cbNode, result);
+                break;
+            case 302 /* CommaListExpression */:
+                result = reduceNodes(node.elements, cbNodes, result);
+                break;
+            default:
+                break;
+        }
+        return result;
+    }
+    ts.reduceEachChild = reduceEachChild;
+    function mergeLexicalEnvironment(statements, declarations) {
+        if (!ts.some(declarations)) {
+            return statements;
+        }
+        return ts.isNodeArray(statements)
+            ? ts.setTextRange(ts.createNodeArray(ts.prependStatements(statements.slice(), declarations)), statements)
+            : ts.prependStatements(statements, declarations);
+    }
+    ts.mergeLexicalEnvironment = mergeLexicalEnvironment;
+    /**
+     * Lifts a NodeArray containing only Statement nodes to a block.
+     *
+     * @param nodes The NodeArray.
+     */
+    function liftToBlock(nodes) {
+        Debug.assert(ts.every(nodes, ts.isStatement), "Cannot lift nodes to a Block.");
+        return ts.singleOrUndefined(nodes) || ts.createBlock(nodes);
+    }
+    ts.liftToBlock = liftToBlock;
+    /**
+     * Aggregates the TransformFlags for a Node and its subtree.
+     */
+    function aggregateTransformFlags(node) {
+        aggregateTransformFlagsForNode(node);
+        return node;
+    }
+    ts.aggregateTransformFlags = aggregateTransformFlags;
+    /**
+     * Aggregates the TransformFlags for a Node and its subtree. The flags for the subtree are
+     * computed first, then the transform flags for the current node are computed from the subtree
+     * flags and the state of the current node. Finally, the transform flags of the node are
+     * returned, excluding any flags that should not be included in its parent node's subtree
+     * flags.
+     */
+    function aggregateTransformFlagsForNode(node) {
+        if (node === undefined) {
+            return 0 /* None */;
+        }
+        if (node.transformFlags & 536870912 /* HasComputedFlags */) {
+            return node.transformFlags & ~ts.getTransformFlagsSubtreeExclusions(node.kind);
+        }
+        var subtreeFlags = aggregateTransformFlagsForSubtree(node);
+        return ts.computeTransformFlagsForNode(node, subtreeFlags);
+    }
+    function aggregateTransformFlagsForNodeArray(nodes) {
+        if (nodes === undefined) {
+            return 0 /* None */;
+        }
+        var subtreeFlags = 0 /* None */;
+        var nodeArrayFlags = 0 /* None */;
+        for (var _i = 0, nodes_3 = nodes; _i < nodes_3.length; _i++) {
+            var node = nodes_3[_i];
+            subtreeFlags |= aggregateTransformFlagsForNode(node);
+            nodeArrayFlags |= node.transformFlags & ~536870912 /* HasComputedFlags */;
+        }
+        nodes.transformFlags = nodeArrayFlags | 536870912 /* HasComputedFlags */;
+        return subtreeFlags;
+    }
+    /**
+     * Aggregates the transform flags for the subtree of a node.
+     */
+    function aggregateTransformFlagsForSubtree(node) {
+        // We do not transform ambient declarations or types, so there is no need to
+        // recursively aggregate transform flags.
+        if (ts.hasModifier(node, 2 /* Ambient */) || (ts.isTypeNode(node) && node.kind !== 207 /* ExpressionWithTypeArguments */)) {
+            return 0 /* None */;
+        }
+        // Aggregate the transform flags of each child.
+        return reduceEachChild(node, 0 /* None */, aggregateTransformFlagsForChildNode, aggregateTransformFlagsForChildNodes);
+    }
+    /**
+     * Aggregates the TransformFlags of a child node with the TransformFlags of its
+     * siblings.
+     */
+    function aggregateTransformFlagsForChildNode(transformFlags, node) {
+        return transformFlags | aggregateTransformFlagsForNode(node);
+    }
+    function aggregateTransformFlagsForChildNodes(transformFlags, nodes) {
+        return transformFlags | aggregateTransformFlagsForNodeArray(nodes);
+    }
+    var Debug;
+    (function (Debug) {
+        var isDebugInfoEnabled = false;
+        function failBadSyntaxKind(node, message) {
+            return Debug.fail((message || "Unexpected node.") + "\r\nNode " + ts.formatSyntaxKind(node.kind) + " was unexpected.", failBadSyntaxKind);
+        }
+        Debug.failBadSyntaxKind = failBadSyntaxKind;
+        Debug.assertEachNode = Debug.shouldAssert(1 /* Normal */)
+            ? function (nodes, test, message) { return Debug.assert(test === undefined || ts.every(nodes, test), message || "Unexpected node.", function () { return "Node array did not pass test '" + Debug.getFunctionName(test) + "'."; }, Debug.assertEachNode); }
+            : ts.noop;
+        Debug.assertNode = Debug.shouldAssert(1 /* Normal */)
+            ? function (node, test, message) { return Debug.assert(test === undefined || test(node), message || "Unexpected node.", function () { return "Node " + ts.formatSyntaxKind(node.kind) + " did not pass test '" + Debug.getFunctionName(test) + "'."; }, Debug.assertNode); }
+            : ts.noop;
+        Debug.assertOptionalNode = Debug.shouldAssert(1 /* Normal */)
+            ? function (node, test, message) { return Debug.assert(test === undefined || node === undefined || test(node), message || "Unexpected node.", function () { return "Node " + ts.formatSyntaxKind(node.kind) + " did not pass test '" + Debug.getFunctionName(test) + "'."; }, Debug.assertOptionalNode); }
+            : ts.noop;
+        Debug.assertOptionalToken = Debug.shouldAssert(1 /* Normal */)
+            ? function (node, kind, message) { return Debug.assert(kind === undefined || node === undefined || node.kind === kind, message || "Unexpected node.", function () { return "Node " + ts.formatSyntaxKind(node.kind) + " was not a '" + ts.formatSyntaxKind(kind) + "' token."; }, Debug.assertOptionalToken); }
+            : ts.noop;
+        Debug.assertMissingNode = Debug.shouldAssert(1 /* Normal */)
+            ? function (node, message) { return Debug.assert(node === undefined, message || "Unexpected node.", function () { return "Node " + ts.formatSyntaxKind(node.kind) + " was unexpected'."; }, Debug.assertMissingNode); }
+            : ts.noop;
+        /**
+         * Injects debug information into frequently used types.
+         */
+        function enableDebugInfo() {
+            if (isDebugInfoEnabled)
+                return;
+            // Add additional properties in debug mode to assist with debugging.
+            Object.defineProperties(ts.objectAllocator.getSymbolConstructor().prototype, {
+                __debugFlags: { get: function () { return ts.formatSymbolFlags(this.flags); } }
+            });
+            Object.defineProperties(ts.objectAllocator.getTypeConstructor().prototype, {
+                __debugFlags: { get: function () { return ts.formatTypeFlags(this.flags); } },
+                __debugObjectFlags: { get: function () { return this.flags & 131072 /* Object */ ? ts.formatObjectFlags(this.objectFlags) : ""; } },
+                __debugTypeToString: { value: function () { return this.checker.typeToString(this); } },
+            });
+            var nodeConstructors = [
+                ts.objectAllocator.getNodeConstructor(),
+                ts.objectAllocator.getIdentifierConstructor(),
+                ts.objectAllocator.getTokenConstructor(),
+                ts.objectAllocator.getSourceFileConstructor()
+            ];
+            for (var _i = 0, nodeConstructors_1 = nodeConstructors; _i < nodeConstructors_1.length; _i++) {
+                var ctor = nodeConstructors_1[_i];
+                if (!ctor.prototype.hasOwnProperty("__debugKind")) {
+                    Object.defineProperties(ctor.prototype, {
+                        __debugKind: { get: function () { return ts.formatSyntaxKind(this.kind); } },
+                        __debugModifierFlags: { get: function () { return ts.formatModifierFlags(ts.getModifierFlagsNoCache(this)); } },
+                        __debugTransformFlags: { get: function () { return ts.formatTransformFlags(this.transformFlags); } },
+                        __debugEmitFlags: { get: function () { return ts.formatEmitFlags(ts.getEmitFlags(this)); } },
+                        __debugGetText: {
+                            value: function (includeTrivia) {
+                                if (ts.nodeIsSynthesized(this))
+                                    return "";
+                                var parseNode = ts.getParseTreeNode(this);
+                                var sourceFile = parseNode && ts.getSourceFileOfNode(parseNode);
+                                return sourceFile ? ts.getSourceTextOfNodeFromSourceFile(sourceFile, parseNode, includeTrivia) : "";
+                            }
+                        }
+                    });
+                }
+            }
+            isDebugInfoEnabled = true;
+        }
+        Debug.enableDebugInfo = enableDebugInfo;
+    })(Debug = ts.Debug || (ts.Debug = {}));
+})(ts || (ts = {}));
+/* @internal */
+var ts;
+(function (ts) {
+    function getOriginalNodeId(node) {
+        node = ts.getOriginalNode(node);
+        return node ? ts.getNodeId(node) : 0;
+    }
+    ts.getOriginalNodeId = getOriginalNodeId;
+    function containsDefaultReference(node) {
+        if (!node)
+            return false;
+        if (!ts.isNamedImports(node))
+            return false;
+        return ts.some(node.elements, isNamedDefaultReference);
+    }
+    function isNamedDefaultReference(e) {
+        return e.propertyName !== undefined && e.propertyName.escapedText === "default" /* Default */;
+    }
+    function chainBundle(transformSourceFile) {
+        return transformSourceFileOrBundle;
+        function transformSourceFileOrBundle(node) {
+            return node.kind === 274 /* SourceFile */ ? transformSourceFile(node) : transformBundle(node);
+        }
+        function transformBundle(node) {
+            return ts.createBundle(ts.map(node.sourceFiles, transformSourceFile), node.prepends);
+        }
+    }
+    ts.chainBundle = chainBundle;
+    function getImportNeedsImportStarHelper(node) {
+        if (!!ts.getNamespaceDeclarationNode(node)) {
+            return true;
+        }
+        var bindings = node.importClause && node.importClause.namedBindings;
+        if (!bindings) {
+            return false;
+        }
+        if (!ts.isNamedImports(bindings))
+            return false;
+        var defaultRefCount = 0;
+        for (var _i = 0, _a = bindings.elements; _i < _a.length; _i++) {
+            var binding = _a[_i];
+            if (isNamedDefaultReference(binding)) {
+                defaultRefCount++;
+            }
+        }
+        // Import star is required if there's default named refs mixed with non-default refs, or if theres non-default refs and it has a default import
+        return (defaultRefCount > 0 && defaultRefCount !== bindings.elements.length) || (!!(bindings.elements.length - defaultRefCount) && ts.isDefaultImport(node));
+    }
+    ts.getImportNeedsImportStarHelper = getImportNeedsImportStarHelper;
+    function getImportNeedsImportDefaultHelper(node) {
+        // Import default is needed if there's a default import or a default ref and no other refs (meaning an import star helper wasn't requested)
+        return !getImportNeedsImportStarHelper(node) && (ts.isDefaultImport(node) || (!!node.importClause && ts.isNamedImports(node.importClause.namedBindings) && containsDefaultReference(node.importClause.namedBindings))); // TODO: GH#18217
+    }
+    ts.getImportNeedsImportDefaultHelper = getImportNeedsImportDefaultHelper;
+    function collectExternalModuleInfo(sourceFile, resolver, compilerOptions) {
+        var externalImports = [];
+        var exportSpecifiers = ts.createMultiMap();
+        var exportedBindings = [];
+        var uniqueExports = ts.createMap();
+        var exportedNames;
+        var hasExportDefault = false;
+        var exportEquals;
+        var hasExportStarsToExportValues = false;
+        var hasImportStarOrImportDefault = false;
+        for (var _i = 0, _a = sourceFile.statements; _i < _a.length; _i++) {
+            var node = _a[_i];
+            switch (node.kind) {
+                case 244 /* ImportDeclaration */:
+                    // import "mod"
+                    // import x from "mod"
+                    // import * as x from "mod"
+                    // import { x, y } from "mod"
+                    externalImports.push(node);
+                    hasImportStarOrImportDefault = hasImportStarOrImportDefault || getImportNeedsImportStarHelper(node) || getImportNeedsImportDefaultHelper(node);
+                    break;
+                case 243 /* ImportEqualsDeclaration */:
+                    if (node.moduleReference.kind === 254 /* ExternalModuleReference */) {
+                        // import x = require("mod")
+                        externalImports.push(node);
+                    }
+                    break;
+                case 250 /* ExportDeclaration */:
+                    if (node.moduleSpecifier) {
+                        if (!node.exportClause) {
+                            // export * from "mod"
+                            externalImports.push(node);
+                            hasExportStarsToExportValues = true;
+                        }
+                        else {
+                            // export { x, y } from "mod"
+                            externalImports.push(node);
+                        }
+                    }
+                    else {
+                        // export { x, y }
+                        for (var _b = 0, _c = node.exportClause.elements; _b < _c.length; _b++) {
+                            var specifier = _c[_b];
+                            if (!uniqueExports.get(ts.idText(specifier.name))) {
+                                var name = specifier.propertyName || specifier.name;
+                                exportSpecifiers.add(ts.idText(name), specifier);
+                                var decl = resolver.getReferencedImportDeclaration(name)
+                                    || resolver.getReferencedValueDeclaration(name);
+                                if (decl) {
+                                    multiMapSparseArrayAdd(exportedBindings, getOriginalNodeId(decl), specifier.name);
+                                }
+                                uniqueExports.set(ts.idText(specifier.name), true);
+                                exportedNames = ts.append(exportedNames, specifier.name);
+                            }
+                        }
+                    }
+                    break;
+                case 249 /* ExportAssignment */:
+                    if (node.isExportEquals && !exportEquals) {
+                        // export = x
+                        exportEquals = node;
+                    }
+                    break;
+                case 214 /* VariableStatement */:
+                    if (ts.hasModifier(node, 1 /* Export */)) {
+                        for (var _d = 0, _e = node.declarationList.declarations; _d < _e.length; _d++) {
+                            var decl = _e[_d];
+                            exportedNames = collectExportedVariableInfo(decl, uniqueExports, exportedNames);
+                        }
+                    }
+                    break;
+                case 234 /* FunctionDeclaration */:
+                    if (ts.hasModifier(node, 1 /* Export */)) {
+                        if (ts.hasModifier(node, 512 /* Default */)) {
+                            // export default function() { }
+                            if (!hasExportDefault) {
+                                multiMapSparseArrayAdd(exportedBindings, getOriginalNodeId(node), ts.getDeclarationName(node));
+                                hasExportDefault = true;
+                            }
+                        }
+                        else {
+                            // export function x() { }
+                            var name = node.name;
+                            if (!uniqueExports.get(ts.idText(name))) {
+                                multiMapSparseArrayAdd(exportedBindings, getOriginalNodeId(node), name);
+                                uniqueExports.set(ts.idText(name), true);
+                                exportedNames = ts.append(exportedNames, name);
+                            }
+                        }
+                    }
+                    break;
+                case 235 /* ClassDeclaration */:
+                    if (ts.hasModifier(node, 1 /* Export */)) {
+                        if (ts.hasModifier(node, 512 /* Default */)) {
+                            // export default class { }
+                            if (!hasExportDefault) {
+                                multiMapSparseArrayAdd(exportedBindings, getOriginalNodeId(node), ts.getDeclarationName(node));
+                                hasExportDefault = true;
+                            }
+                        }
+                        else {
+                            // export class x { }
+                            var name = node.name;
+                            if (name && !uniqueExports.get(ts.idText(name))) {
+                                multiMapSparseArrayAdd(exportedBindings, getOriginalNodeId(node), name);
+                                uniqueExports.set(ts.idText(name), true);
+                                exportedNames = ts.append(exportedNames, name);
+                            }
+                        }
+                    }
+                    break;
+            }
+        }
+        var externalHelpersModuleName = ts.getOrCreateExternalHelpersModuleNameIfNeeded(sourceFile, compilerOptions, hasExportStarsToExportValues, hasImportStarOrImportDefault);
+        var externalHelpersImportDeclaration = externalHelpersModuleName && ts.createImportDeclaration(
+        /*decorators*/ undefined, 
+        /*modifiers*/ undefined, ts.createImportClause(/*name*/ undefined, ts.createNamespaceImport(externalHelpersModuleName)), ts.createLiteral(ts.externalHelpersModuleNameText));
+        if (externalHelpersImportDeclaration) {
+            ts.addEmitFlags(externalHelpersImportDeclaration, 67108864 /* NeverApplyImportHelper */);
+            externalImports.unshift(externalHelpersImportDeclaration);
+        }
+        return { externalImports: externalImports, exportSpecifiers: exportSpecifiers, exportEquals: exportEquals, hasExportStarsToExportValues: hasExportStarsToExportValues, exportedBindings: exportedBindings, exportedNames: exportedNames, externalHelpersImportDeclaration: externalHelpersImportDeclaration };
+    }
+    ts.collectExternalModuleInfo = collectExternalModuleInfo;
+    function collectExportedVariableInfo(decl, uniqueExports, exportedNames) {
+        if (ts.isBindingPattern(decl.name)) {
+            for (var _i = 0, _a = decl.name.elements; _i < _a.length; _i++) {
+                var element = _a[_i];
+                if (!ts.isOmittedExpression(element)) {
+                    exportedNames = collectExportedVariableInfo(element, uniqueExports, exportedNames);
+                }
+            }
+        }
+        else if (!ts.isGeneratedIdentifier(decl.name)) {
+            var text = ts.idText(decl.name);
+            if (!uniqueExports.get(text)) {
+                uniqueExports.set(text, true);
+                exportedNames = ts.append(exportedNames, decl.name);
+            }
+        }
+        return exportedNames;
+    }
+    /** Use a sparse array as a multi-map. */
+    function multiMapSparseArrayAdd(map, key, value) {
+        var values = map[key];
+        if (values) {
+            values.push(value);
+        }
+        else {
+            map[key] = values = [value];
+        }
+        return values;
+    }
+    /**
+     * Used in the module transformer to check if an expression is reasonably without sideeffect,
+     *  and thus better to copy into multiple places rather than to cache in a temporary variable
+     *  - this is mostly subjective beyond the requirement that the expression not be sideeffecting
+     */
+    function isSimpleCopiableExpression(expression) {
+        return ts.isStringLiteralLike(expression) ||
+            expression.kind === 8 /* NumericLiteral */ ||
+            ts.isKeyword(expression.kind) ||
+            ts.isIdentifier(expression);
+    }
+    ts.isSimpleCopiableExpression = isSimpleCopiableExpression;
+    /**
+     * @param input Template string input strings
+     * @param args Names which need to be made file-level unique
+     */
+    function helperString(input) {
+        var args = [];
+        for (var _i = 1; _i < arguments.length; _i++) {
+            args[_i - 1] = arguments[_i];
+        }
+        return function (uniqueName) {
+            var result = "";
+            for (var i = 0; i < args.length; i++) {
+                result += input[i];
+                result += uniqueName(args[i]);
+            }
+            result += input[input.length - 1];
+            return result;
+        };
+    }
+    ts.helperString = helperString;
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    var FlattenLevel;
+    (function (FlattenLevel) {
+        FlattenLevel[FlattenLevel["All"] = 0] = "All";
+        FlattenLevel[FlattenLevel["ObjectRest"] = 1] = "ObjectRest";
+    })(FlattenLevel = ts.FlattenLevel || (ts.FlattenLevel = {}));
+    /**
+     * Flattens a DestructuringAssignment or a VariableDeclaration to an expression.
+     *
+     * @param node The node to flatten.
+     * @param visitor An optional visitor used to visit initializers.
+     * @param context The transformation context.
+     * @param level Indicates the extent to which flattening should occur.
+     * @param needsValue An optional value indicating whether the value from the right-hand-side of
+     * the destructuring assignment is needed as part of a larger expression.
+     * @param createAssignmentCallback An optional callback used to create the assignment expression.
+     */
+    function flattenDestructuringAssignment(node, visitor, context, level, needsValue, createAssignmentCallback) {
+        var location = node;
+        var value;
+        if (ts.isDestructuringAssignment(node)) {
+            value = node.right;
+            while (ts.isEmptyArrayLiteral(node.left) || ts.isEmptyObjectLiteral(node.left)) {
+                if (ts.isDestructuringAssignment(value)) {
+                    location = node = value;
+                    value = node.right;
+                }
+                else {
+                    return ts.visitNode(value, visitor, ts.isExpression);
+                }
+            }
+        }
+        var expressions;
+        var flattenContext = {
+            context: context,
+            level: level,
+            downlevelIteration: !!context.getCompilerOptions().downlevelIteration,
+            hoistTempVariables: true,
+            emitExpression: emitExpression,
+            emitBindingOrAssignment: emitBindingOrAssignment,
+            createArrayBindingOrAssignmentPattern: makeArrayAssignmentPattern,
+            createObjectBindingOrAssignmentPattern: makeObjectAssignmentPattern,
+            createArrayBindingOrAssignmentElement: makeAssignmentElement,
+            visitor: visitor
+        };
+        if (value) {
+            value = ts.visitNode(value, visitor, ts.isExpression);
+            if (ts.isIdentifier(value) && bindingOrAssignmentElementAssignsToName(node, value.escapedText)) {
+                // If the right-hand value of the assignment is also an assignment target then
+                // we need to cache the right-hand value.
+                value = ensureIdentifier(flattenContext, value, /*reuseIdentifierExpressions*/ false, location);
+            }
+            else if (needsValue) {
+                // If the right-hand value of the destructuring assignment needs to be preserved (as
+                // is the case when the destructuring assignment is part of a larger expression),
+                // then we need to cache the right-hand value.
+                //
+                // The source map location for the assignment should point to the entire binary
+                // expression.
+                value = ensureIdentifier(flattenContext, value, /*reuseIdentifierExpressions*/ true, location);
+            }
+            else if (ts.nodeIsSynthesized(node)) {
+                // Generally, the source map location for a destructuring assignment is the root
+                // expression.
+                //
+                // However, if the root expression is synthesized (as in the case
+                // of the initializer when transforming a ForOfStatement), then the source map
+                // location should point to the right-hand value of the expression.
+                location = value;
+            }
+        }
+        flattenBindingOrAssignmentElement(flattenContext, node, value, location, /*skipInitializer*/ ts.isDestructuringAssignment(node));
+        if (value && needsValue) {
+            if (!ts.some(expressions)) {
+                return value;
+            }
+            expressions.push(value);
+        }
+        return ts.aggregateTransformFlags(ts.inlineExpressions(expressions)) || ts.createOmittedExpression();
+        function emitExpression(expression) {
+            // NOTE: this completely disables source maps, but aligns with the behavior of
+            //       `emitAssignment` in the old emitter.
+            ts.setEmitFlags(expression, 64 /* NoNestedSourceMaps */);
+            ts.aggregateTransformFlags(expression);
+            expressions = ts.append(expressions, expression);
+        }
+        function emitBindingOrAssignment(target, value, location, original) {
+            ts.Debug.assertNode(target, createAssignmentCallback ? ts.isIdentifier : ts.isExpression);
+            var expression = createAssignmentCallback
+                ? createAssignmentCallback(target, value, location)
+                : ts.setTextRange(ts.createAssignment(ts.visitNode(target, visitor, ts.isExpression), value), location);
+            expression.original = original;
+            emitExpression(expression);
+        }
+    }
+    ts.flattenDestructuringAssignment = flattenDestructuringAssignment;
+    function bindingOrAssignmentElementAssignsToName(element, escapedName) {
+        var target = ts.getTargetOfBindingOrAssignmentElement(element); // TODO: GH#18217
+        if (ts.isBindingOrAssignmentPattern(target)) {
+            return bindingOrAssignmentPatternAssignsToName(target, escapedName);
+        }
+        else if (ts.isIdentifier(target)) {
+            return target.escapedText === escapedName;
+        }
+        return false;
+    }
+    function bindingOrAssignmentPatternAssignsToName(pattern, escapedName) {
+        var elements = ts.getElementsOfBindingOrAssignmentPattern(pattern);
+        for (var _i = 0, elements_3 = elements; _i < elements_3.length; _i++) {
+            var element = elements_3[_i];
+            if (bindingOrAssignmentElementAssignsToName(element, escapedName)) {
+                return true;
+            }
+        }
+        return false;
+    }
+    /**
+     * Flattens a VariableDeclaration or ParameterDeclaration to one or more variable declarations.
+     *
+     * @param node The node to flatten.
+     * @param visitor An optional visitor used to visit initializers.
+     * @param context The transformation context.
+     * @param boundValue The value bound to the declaration.
+     * @param skipInitializer A value indicating whether to ignore the initializer of `node`.
+     * @param hoistTempVariables Indicates whether temporary variables should not be recorded in-line.
+     * @param level Indicates the extent to which flattening should occur.
+     */
+    function flattenDestructuringBinding(node, visitor, context, level, rval, hoistTempVariables, skipInitializer) {
+        if (hoistTempVariables === void 0) { hoistTempVariables = false; }
+        var pendingExpressions;
+        var pendingDeclarations = [];
+        var declarations = [];
+        var flattenContext = {
+            context: context,
+            level: level,
+            downlevelIteration: !!context.getCompilerOptions().downlevelIteration,
+            hoistTempVariables: hoistTempVariables,
+            emitExpression: emitExpression,
+            emitBindingOrAssignment: emitBindingOrAssignment,
+            createArrayBindingOrAssignmentPattern: makeArrayBindingPattern,
+            createObjectBindingOrAssignmentPattern: makeObjectBindingPattern,
+            createArrayBindingOrAssignmentElement: makeBindingElement,
+            visitor: visitor
+        };
+        if (ts.isVariableDeclaration(node)) {
+            var initializer = ts.getInitializerOfBindingOrAssignmentElement(node);
+            if (initializer && ts.isIdentifier(initializer) && bindingOrAssignmentElementAssignsToName(node, initializer.escapedText)) {
+                // If the right-hand value of the assignment is also an assignment target then
+                // we need to cache the right-hand value.
+                initializer = ensureIdentifier(flattenContext, initializer, /*reuseIdentifierExpressions*/ false, initializer);
+                node = ts.updateVariableDeclaration(node, node.name, node.type, initializer);
+            }
+        }
+        flattenBindingOrAssignmentElement(flattenContext, node, rval, node, skipInitializer);
+        if (pendingExpressions) {
+            var temp = ts.createTempVariable(/*recordTempVariable*/ undefined);
+            if (hoistTempVariables) {
+                var value = ts.inlineExpressions(pendingExpressions);
+                pendingExpressions = undefined;
+                emitBindingOrAssignment(temp, value, /*location*/ undefined, /*original*/ undefined);
+            }
+            else {
+                context.hoistVariableDeclaration(temp);
+                var pendingDeclaration = ts.last(pendingDeclarations);
+                pendingDeclaration.pendingExpressions = ts.append(pendingDeclaration.pendingExpressions, ts.createAssignment(temp, pendingDeclaration.value));
+                ts.addRange(pendingDeclaration.pendingExpressions, pendingExpressions);
+                pendingDeclaration.value = temp;
+            }
+        }
+        for (var _i = 0, pendingDeclarations_1 = pendingDeclarations; _i < pendingDeclarations_1.length; _i++) {
+            var _a = pendingDeclarations_1[_i], pendingExpressions_1 = _a.pendingExpressions, name = _a.name, value = _a.value, location = _a.location, original = _a.original;
+            var variable = ts.createVariableDeclaration(name, 
+            /*type*/ undefined, pendingExpressions_1 ? ts.inlineExpressions(ts.append(pendingExpressions_1, value)) : value);
+            variable.original = original;
+            ts.setTextRange(variable, location);
+            if (ts.isIdentifier(name)) {
+                ts.setEmitFlags(variable, 64 /* NoNestedSourceMaps */);
+            }
+            ts.aggregateTransformFlags(variable);
+            declarations.push(variable);
+        }
+        return declarations;
+        function emitExpression(value) {
+            pendingExpressions = ts.append(pendingExpressions, value);
+        }
+        function emitBindingOrAssignment(target, value, location, original) {
+            ts.Debug.assertNode(target, ts.isBindingName);
+            if (pendingExpressions) {
+                value = ts.inlineExpressions(ts.append(pendingExpressions, value));
+                pendingExpressions = undefined;
+            }
+            pendingDeclarations.push({ pendingExpressions: pendingExpressions, name: target, value: value, location: location, original: original });
+        }
+    }
+    ts.flattenDestructuringBinding = flattenDestructuringBinding;
+    /**
+     * Flattens a BindingOrAssignmentElement into zero or more bindings or assignments.
+     *
+     * @param flattenContext Options used to control flattening.
+     * @param element The element to flatten.
+     * @param value The current RHS value to assign to the element.
+     * @param location The location to use for source maps and comments.
+     * @param skipInitializer An optional value indicating whether to include the initializer
+     * for the element.
+     */
+    function flattenBindingOrAssignmentElement(flattenContext, element, value, location, skipInitializer) {
+        if (!skipInitializer) {
+            var initializer = ts.visitNode(ts.getInitializerOfBindingOrAssignmentElement(element), flattenContext.visitor, ts.isExpression);
+            if (initializer) {
+                // Combine value and initializer
+                value = value ? createDefaultValueCheck(flattenContext, value, initializer, location) : initializer;
+            }
+            else if (!value) {
+                // Use 'void 0' in absence of value and initializer
+                value = ts.createVoidZero();
+            }
+        }
+        var bindingTarget = ts.getTargetOfBindingOrAssignmentElement(element); // TODO: GH#18217
+        if (ts.isObjectBindingOrAssignmentPattern(bindingTarget)) {
+            flattenObjectBindingOrAssignmentPattern(flattenContext, element, bindingTarget, value, location);
+        }
+        else if (ts.isArrayBindingOrAssignmentPattern(bindingTarget)) {
+            flattenArrayBindingOrAssignmentPattern(flattenContext, element, bindingTarget, value, location);
+        }
+        else {
+            flattenContext.emitBindingOrAssignment(bindingTarget, value, location, /*original*/ element); // TODO: GH#18217
+        }
+    }
+    /**
+     * Flattens an ObjectBindingOrAssignmentPattern into zero or more bindings or assignments.
+     *
+     * @param flattenContext Options used to control flattening.
+     * @param parent The parent element of the pattern.
+     * @param pattern The ObjectBindingOrAssignmentPattern to flatten.
+     * @param value The current RHS value to assign to the element.
+     * @param location The location to use for source maps and comments.
+     */
+    function flattenObjectBindingOrAssignmentPattern(flattenContext, parent, pattern, value, location) {
+        var elements = ts.getElementsOfBindingOrAssignmentPattern(pattern);
+        var numElements = elements.length;
+        if (numElements !== 1) {
+            // For anything other than a single-element destructuring we need to generate a temporary
+            // to ensure value is evaluated exactly once. Additionally, if we have zero elements
+            // we need to emit *something* to ensure that in case a 'var' keyword was already emitted,
+            // so in that case, we'll intentionally create that temporary.
+            var reuseIdentifierExpressions = !ts.isDeclarationBindingElement(parent) || numElements !== 0;
+            value = ensureIdentifier(flattenContext, value, reuseIdentifierExpressions, location);
+        }
+        var bindingElements;
+        var computedTempVariables;
+        for (var i = 0; i < numElements; i++) {
+            var element = elements[i];
+            if (!ts.getRestIndicatorOfBindingOrAssignmentElement(element)) {
+                var propertyName = ts.getPropertyNameOfBindingOrAssignmentElement(element);
+                if (flattenContext.level >= 1 /* ObjectRest */
+                    && !(element.transformFlags & (524288 /* ContainsRest */ | 1048576 /* ContainsObjectRest */))
+                    && !(ts.getTargetOfBindingOrAssignmentElement(element).transformFlags & (524288 /* ContainsRest */ | 1048576 /* ContainsObjectRest */))
+                    && !ts.isComputedPropertyName(propertyName)) {
+                    bindingElements = ts.append(bindingElements, element);
+                }
+                else {
+                    if (bindingElements) {
+                        flattenContext.emitBindingOrAssignment(flattenContext.createObjectBindingOrAssignmentPattern(bindingElements), value, location, pattern);
+                        bindingElements = undefined;
+                    }
+                    var rhsValue = createDestructuringPropertyAccess(flattenContext, value, propertyName);
+                    if (ts.isComputedPropertyName(propertyName)) {
+                        computedTempVariables = ts.append(computedTempVariables, rhsValue.argumentExpression);
+                    }
+                    flattenBindingOrAssignmentElement(flattenContext, element, rhsValue, /*location*/ element);
+                }
+            }
+            else if (i === numElements - 1) {
+                if (bindingElements) {
+                    flattenContext.emitBindingOrAssignment(flattenContext.createObjectBindingOrAssignmentPattern(bindingElements), value, location, pattern);
+                    bindingElements = undefined;
+                }
+                var rhsValue = createRestCall(flattenContext.context, value, elements, computedTempVariables, pattern); // TODO: GH#18217
+                flattenBindingOrAssignmentElement(flattenContext, element, rhsValue, element);
+            }
+        }
+        if (bindingElements) {
+            flattenContext.emitBindingOrAssignment(flattenContext.createObjectBindingOrAssignmentPattern(bindingElements), value, location, pattern);
+        }
+    }
+    /**
+     * Flattens an ArrayBindingOrAssignmentPattern into zero or more bindings or assignments.
+     *
+     * @param flattenContext Options used to control flattening.
+     * @param parent The parent element of the pattern.
+     * @param pattern The ArrayBindingOrAssignmentPattern to flatten.
+     * @param value The current RHS value to assign to the element.
+     * @param location The location to use for source maps and comments.
+     */
+    function flattenArrayBindingOrAssignmentPattern(flattenContext, parent, pattern, value, location) {
+        var elements = ts.getElementsOfBindingOrAssignmentPattern(pattern);
+        var numElements = elements.length;
+        if (flattenContext.level < 1 /* ObjectRest */ && flattenContext.downlevelIteration) {
+            // Read the elements of the iterable into an array
+            value = ensureIdentifier(flattenContext, ts.createReadHelper(flattenContext.context, value, numElements > 0 && ts.getRestIndicatorOfBindingOrAssignmentElement(elements[numElements - 1])
+                ? undefined
+                : numElements, location), 
+            /*reuseIdentifierExpressions*/ false, location);
+        }
+        else if (numElements !== 1 && (flattenContext.level < 1 /* ObjectRest */ || numElements === 0)
+            || ts.every(elements, ts.isOmittedExpression)) {
+            // For anything other than a single-element destructuring we need to generate a temporary
+            // to ensure value is evaluated exactly once. Additionally, if we have zero elements
+            // we need to emit *something* to ensure that in case a 'var' keyword was already emitted,
+            // so in that case, we'll intentionally create that temporary.
+            // Or all the elements of the binding pattern are omitted expression such as "var [,] = [1,2]",
+            // then we will create temporary variable.
+            var reuseIdentifierExpressions = !ts.isDeclarationBindingElement(parent) || numElements !== 0;
+            value = ensureIdentifier(flattenContext, value, reuseIdentifierExpressions, location);
+        }
+        var bindingElements;
+        var restContainingElements;
+        for (var i = 0; i < numElements; i++) {
+            var element = elements[i];
+            if (flattenContext.level >= 1 /* ObjectRest */) {
+                // If an array pattern contains an ObjectRest, we must cache the result so that we
+                // can perform the ObjectRest destructuring in a different declaration
+                if (element.transformFlags & 1048576 /* ContainsObjectRest */) {
+                    var temp = ts.createTempVariable(/*recordTempVariable*/ undefined);
+                    if (flattenContext.hoistTempVariables) {
+                        flattenContext.context.hoistVariableDeclaration(temp);
+                    }
+                    restContainingElements = ts.append(restContainingElements, [temp, element]);
+                    bindingElements = ts.append(bindingElements, flattenContext.createArrayBindingOrAssignmentElement(temp));
+                }
+                else {
+                    bindingElements = ts.append(bindingElements, element);
+                }
+            }
+            else if (ts.isOmittedExpression(element)) {
+                continue;
+            }
+            else if (!ts.getRestIndicatorOfBindingOrAssignmentElement(element)) {
+                var rhsValue = ts.createElementAccess(value, i);
+                flattenBindingOrAssignmentElement(flattenContext, element, rhsValue, /*location*/ element);
+            }
+            else if (i === numElements - 1) {
+                var rhsValue = ts.createArraySlice(value, i);
+                flattenBindingOrAssignmentElement(flattenContext, element, rhsValue, /*location*/ element);
+            }
+        }
+        if (bindingElements) {
+            flattenContext.emitBindingOrAssignment(flattenContext.createArrayBindingOrAssignmentPattern(bindingElements), value, location, pattern);
+        }
+        if (restContainingElements) {
+            for (var _i = 0, restContainingElements_1 = restContainingElements; _i < restContainingElements_1.length; _i++) {
+                var _a = restContainingElements_1[_i], id = _a[0], element = _a[1];
+                flattenBindingOrAssignmentElement(flattenContext, element, id, element);
+            }
+        }
+    }
+    /**
+     * Creates an expression used to provide a default value if a value is `undefined` at runtime.
+     *
+     * @param flattenContext Options used to control flattening.
+     * @param value The RHS value to test.
+     * @param defaultValue The default value to use if `value` is `undefined` at runtime.
+     * @param location The location to use for source maps and comments.
+     */
+    function createDefaultValueCheck(flattenContext, value, defaultValue, location) {
+        value = ensureIdentifier(flattenContext, value, /*reuseIdentifierExpressions*/ true, location);
+        return ts.createConditional(ts.createTypeCheck(value, "undefined"), defaultValue, value);
+    }
+    /**
+     * Creates either a PropertyAccessExpression or an ElementAccessExpression for the
+     * right-hand side of a transformed destructuring assignment.
+     *
+     * @link https://tc39.github.io/ecma262/#sec-runtime-semantics-keyeddestructuringassignmentevaluation
+     *
+     * @param flattenContext Options used to control flattening.
+     * @param value The RHS value that is the source of the property.
+     * @param propertyName The destructuring property name.
+     */
+    function createDestructuringPropertyAccess(flattenContext, value, propertyName) {
+        if (ts.isComputedPropertyName(propertyName)) {
+            var argumentExpression = ensureIdentifier(flattenContext, ts.visitNode(propertyName.expression, flattenContext.visitor), /*reuseIdentifierExpressions*/ false, /*location*/ propertyName);
+            return ts.createElementAccess(value, argumentExpression);
+        }
+        else if (ts.isStringOrNumericLiteral(propertyName)) {
+            var argumentExpression = ts.getSynthesizedClone(propertyName);
+            argumentExpression.text = argumentExpression.text;
+            return ts.createElementAccess(value, argumentExpression);
+        }
+        else {
+            var name = ts.createIdentifier(ts.idText(propertyName));
+            return ts.createPropertyAccess(value, name);
+        }
+    }
+    /**
+     * Ensures that there exists a declared identifier whose value holds the given expression.
+     * This function is useful to ensure that the expression's value can be read from in subsequent expressions.
+     * Unless 'reuseIdentifierExpressions' is false, 'value' will be returned if it is just an identifier.
+     *
+     * @param flattenContext Options used to control flattening.
+     * @param value the expression whose value needs to be bound.
+     * @param reuseIdentifierExpressions true if identifier expressions can simply be returned;
+     * false if it is necessary to always emit an identifier.
+     * @param location The location to use for source maps and comments.
+     */
+    function ensureIdentifier(flattenContext, value, reuseIdentifierExpressions, location) {
+        if (ts.isIdentifier(value) && reuseIdentifierExpressions) {
+            return value;
+        }
+        else {
+            var temp = ts.createTempVariable(/*recordTempVariable*/ undefined);
+            if (flattenContext.hoistTempVariables) {
+                flattenContext.context.hoistVariableDeclaration(temp);
+                flattenContext.emitExpression(ts.setTextRange(ts.createAssignment(temp, value), location));
+            }
+            else {
+                flattenContext.emitBindingOrAssignment(temp, value, location, /*original*/ undefined);
+            }
+            return temp;
+        }
+    }
+    function makeArrayBindingPattern(elements) {
+        ts.Debug.assertEachNode(elements, ts.isArrayBindingElement);
+        return ts.createArrayBindingPattern(elements);
+    }
+    function makeArrayAssignmentPattern(elements) {
+        return ts.createArrayLiteral(ts.map(elements, ts.convertToArrayAssignmentElement));
+    }
+    function makeObjectBindingPattern(elements) {
+        ts.Debug.assertEachNode(elements, ts.isBindingElement);
+        return ts.createObjectBindingPattern(elements);
+    }
+    function makeObjectAssignmentPattern(elements) {
+        return ts.createObjectLiteral(ts.map(elements, ts.convertToObjectAssignmentElement));
+    }
+    function makeBindingElement(name) {
+        return ts.createBindingElement(/*dotDotDotToken*/ undefined, /*propertyName*/ undefined, name);
+    }
+    function makeAssignmentElement(name) {
+        return name;
+    }
+    var restHelper = {
+        name: "typescript:rest",
+        scoped: false,
+        text: "\n            var __rest = (this && this.__rest) || function (s, e) {\n                var t = {};\n                for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p) && e.indexOf(p) < 0)\n                    t[p] = s[p];\n                if (s != null && typeof Object.getOwnPropertySymbols === \"function\")\n                    for (var i = 0, p = Object.getOwnPropertySymbols(s); i < p.length; i++) if (e.indexOf(p[i]) < 0)\n                        t[p[i]] = s[p[i]];\n                return t;\n            };"
+    };
+    /** Given value: o, propName: p, pattern: { a, b, ...p } from the original statement
+     * `{ a, b, ...p } = o`, create `p = __rest(o, ["a", "b"]);`
+     */
+    function createRestCall(context, value, elements, computedTempVariables, location) {
+        context.requestEmitHelper(restHelper);
+        var propertyNames = [];
+        var computedTempVariableOffset = 0;
+        for (var i = 0; i < elements.length - 1; i++) {
+            var propertyName = ts.getPropertyNameOfBindingOrAssignmentElement(elements[i]);
+            if (propertyName) {
+                if (ts.isComputedPropertyName(propertyName)) {
+                    var temp = computedTempVariables[computedTempVariableOffset];
+                    computedTempVariableOffset++;
+                    // typeof _tmp === "symbol" ? _tmp : _tmp + ""
+                    propertyNames.push(ts.createConditional(ts.createTypeCheck(temp, "symbol"), temp, ts.createAdd(temp, ts.createLiteral(""))));
+                }
+                else {
+                    propertyNames.push(ts.createLiteral(propertyName));
+                }
+            }
+        }
+        return ts.createCall(ts.getHelperName("__rest"), 
+        /*typeArguments*/ undefined, [
+            value,
+            ts.setTextRange(ts.createArrayLiteral(propertyNames), location)
+        ]);
+    }
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    /**
+     * Indicates whether to emit type metadata in the new format.
+     */
+    var USE_NEW_TYPE_METADATA_FORMAT = false;
+    var TypeScriptSubstitutionFlags;
+    (function (TypeScriptSubstitutionFlags) {
+        /** Enables substitutions for decorated classes. */
+        TypeScriptSubstitutionFlags[TypeScriptSubstitutionFlags["ClassAliases"] = 1] = "ClassAliases";
+        /** Enables substitutions for namespace exports. */
+        TypeScriptSubstitutionFlags[TypeScriptSubstitutionFlags["NamespaceExports"] = 2] = "NamespaceExports";
+        /* Enables substitutions for unqualified enum members */
+        TypeScriptSubstitutionFlags[TypeScriptSubstitutionFlags["NonQualifiedEnumMembers"] = 8] = "NonQualifiedEnumMembers";
+    })(TypeScriptSubstitutionFlags || (TypeScriptSubstitutionFlags = {}));
+    var ClassFacts;
+    (function (ClassFacts) {
+        ClassFacts[ClassFacts["None"] = 0] = "None";
+        ClassFacts[ClassFacts["HasStaticInitializedProperties"] = 1] = "HasStaticInitializedProperties";
+        ClassFacts[ClassFacts["HasConstructorDecorators"] = 2] = "HasConstructorDecorators";
+        ClassFacts[ClassFacts["HasMemberDecorators"] = 4] = "HasMemberDecorators";
+        ClassFacts[ClassFacts["IsExportOfNamespace"] = 8] = "IsExportOfNamespace";
+        ClassFacts[ClassFacts["IsNamedExternalExport"] = 16] = "IsNamedExternalExport";
+        ClassFacts[ClassFacts["IsDefaultExternalExport"] = 32] = "IsDefaultExternalExport";
+        ClassFacts[ClassFacts["IsDerivedClass"] = 64] = "IsDerivedClass";
+        ClassFacts[ClassFacts["UseImmediatelyInvokedFunctionExpression"] = 128] = "UseImmediatelyInvokedFunctionExpression";
+        ClassFacts[ClassFacts["HasAnyDecorators"] = 6] = "HasAnyDecorators";
+        ClassFacts[ClassFacts["NeedsName"] = 5] = "NeedsName";
+        ClassFacts[ClassFacts["MayNeedImmediatelyInvokedFunctionExpression"] = 7] = "MayNeedImmediatelyInvokedFunctionExpression";
+        ClassFacts[ClassFacts["IsExported"] = 56] = "IsExported";
+    })(ClassFacts || (ClassFacts = {}));
+    function transformTypeScript(context) {
+        var startLexicalEnvironment = context.startLexicalEnvironment, resumeLexicalEnvironment = context.resumeLexicalEnvironment, endLexicalEnvironment = context.endLexicalEnvironment, hoistVariableDeclaration = context.hoistVariableDeclaration;
+        var resolver = context.getEmitResolver();
+        var compilerOptions = context.getCompilerOptions();
+        var strictNullChecks = ts.getStrictOptionValue(compilerOptions, "strictNullChecks");
+        var languageVersion = ts.getEmitScriptTarget(compilerOptions);
+        var moduleKind = ts.getEmitModuleKind(compilerOptions);
+        // Save the previous transformation hooks.
+        var previousOnEmitNode = context.onEmitNode;
+        var previousOnSubstituteNode = context.onSubstituteNode;
+        // Set new transformation hooks.
+        context.onEmitNode = onEmitNode;
+        context.onSubstituteNode = onSubstituteNode;
+        // Enable substitution for property/element access to emit const enum values.
+        context.enableSubstitution(185 /* PropertyAccessExpression */);
+        context.enableSubstitution(186 /* ElementAccessExpression */);
+        // These variables contain state that changes as we descend into the tree.
+        var currentSourceFile;
+        var currentNamespace;
+        var currentNamespaceContainerName;
+        var currentScope;
+        var currentScopeFirstDeclarationsOfName;
+        /**
+         * Keeps track of whether expression substitution has been enabled for specific edge cases.
+         * They are persisted between each SourceFile transformation and should not be reset.
+         */
+        var enabledSubstitutions;
+        /**
+         * A map that keeps track of aliases created for classes with decorators to avoid issues
+         * with the double-binding behavior of classes.
+         */
+        var classAliases;
+        /**
+         * Keeps track of whether we are within any containing namespaces when performing
+         * just-in-time substitution while printing an expression identifier.
+         */
+        var applicableSubstitutions;
+        /**
+         * Tracks what computed name expressions originating from elided names must be inlined
+         * at the next execution site, in document order
+         */
+        var pendingExpressions;
+        return transformSourceFileOrBundle;
+        function transformSourceFileOrBundle(node) {
+            if (node.kind === 275 /* Bundle */) {
+                return transformBundle(node);
+            }
+            return transformSourceFile(node);
+        }
+        function transformBundle(node) {
+            return ts.createBundle(node.sourceFiles.map(transformSourceFile), ts.mapDefined(node.prepends, function (prepend) {
+                if (prepend.kind === 277 /* InputFiles */) {
+                    return ts.createUnparsedSourceFile(prepend.javascriptText, prepend.javascriptMapText);
+                }
+                return prepend;
+            }));
+        }
+        /**
+         * Transform TypeScript-specific syntax in a SourceFile.
+         *
+         * @param node A SourceFile node.
+         */
+        function transformSourceFile(node) {
+            if (node.isDeclarationFile) {
+                return node;
+            }
+            currentSourceFile = node;
+            var visited = saveStateAndInvoke(node, visitSourceFile);
+            ts.addEmitHelpers(visited, context.readEmitHelpers());
+            currentSourceFile = undefined;
+            return visited;
+        }
+        /**
+         * Visits a node, saving and restoring state variables on the stack.
+         *
+         * @param node The node to visit.
+         */
+        function saveStateAndInvoke(node, f) {
+            // Save state
+            var savedCurrentScope = currentScope;
+            var savedCurrentScopeFirstDeclarationsOfName = currentScopeFirstDeclarationsOfName;
+            // Handle state changes before visiting a node.
+            onBeforeVisitNode(node);
+            var visited = f(node);
+            // Restore state
+            if (currentScope !== savedCurrentScope) {
+                currentScopeFirstDeclarationsOfName = savedCurrentScopeFirstDeclarationsOfName;
+            }
+            currentScope = savedCurrentScope;
+            return visited;
+        }
+        /**
+         * Performs actions that should always occur immediately before visiting a node.
+         *
+         * @param node The node to visit.
+         */
+        function onBeforeVisitNode(node) {
+            switch (node.kind) {
+                case 274 /* SourceFile */:
+                case 241 /* CaseBlock */:
+                case 240 /* ModuleBlock */:
+                case 213 /* Block */:
+                    currentScope = node;
+                    currentScopeFirstDeclarationsOfName = undefined;
+                    break;
+                case 235 /* ClassDeclaration */:
+                case 234 /* FunctionDeclaration */:
+                    if (ts.hasModifier(node, 2 /* Ambient */)) {
+                        break;
+                    }
+                    // Record these declarations provided that they have a name.
+                    if (node.name) {
+                        recordEmittedDeclarationInScope(node);
+                    }
+                    else {
+                        // These nodes should always have names unless they are default-exports;
+                        // however, class declaration parsing allows for undefined names, so syntactically invalid
+                        // programs may also have an undefined name.
+                        ts.Debug.assert(node.kind === 235 /* ClassDeclaration */ || ts.hasModifier(node, 512 /* Default */));
+                    }
+                    break;
+            }
+        }
+        /**
+         * General-purpose node visitor.
+         *
+         * @param node The node to visit.
+         */
+        function visitor(node) {
+            return saveStateAndInvoke(node, visitorWorker);
+        }
+        /**
+         * Visits and possibly transforms any node.
+         *
+         * @param node The node to visit.
+         */
+        function visitorWorker(node) {
+            if (node.transformFlags & 1 /* TypeScript */) {
+                // This node is explicitly marked as TypeScript, so we should transform the node.
+                return visitTypeScript(node);
+            }
+            else if (node.transformFlags & 2 /* ContainsTypeScript */) {
+                // This node contains TypeScript, so we should visit its children.
+                return ts.visitEachChild(node, visitor, context);
+            }
+            return node;
+        }
+        /**
+         * Specialized visitor that visits the immediate children of a SourceFile.
+         *
+         * @param node The node to visit.
+         */
+        function sourceElementVisitor(node) {
+            return saveStateAndInvoke(node, sourceElementVisitorWorker);
+        }
+        /**
+         * Specialized visitor that visits the immediate children of a SourceFile.
+         *
+         * @param node The node to visit.
+         */
+        function sourceElementVisitorWorker(node) {
+            switch (node.kind) {
+                case 244 /* ImportDeclaration */:
+                case 243 /* ImportEqualsDeclaration */:
+                case 249 /* ExportAssignment */:
+                case 250 /* ExportDeclaration */:
+                    return visitEllidableStatement(node);
+                default:
+                    return visitorWorker(node);
+            }
+        }
+        function visitEllidableStatement(node) {
+            var parsed = ts.getParseTreeNode(node);
+            if (parsed !== node) {
+                // If the node has been transformed by a `before` transformer, perform no ellision on it
+                // As the type information we would attempt to lookup to perform ellision is potentially unavailable for the synthesized nodes
+                // We do not reuse `visitorWorker`, as the ellidable statement syntax kinds are technically unrecognized by the switch-case in `visitTypeScript`,
+                // and will trigger debug failures when debug verbosity is turned up
+                if (node.transformFlags & 2 /* ContainsTypeScript */) {
+                    // This node contains TypeScript, so we should visit its children.
+                    return ts.visitEachChild(node, visitor, context);
+                }
+                // Otherwise, we can just return the node
+                return node;
+            }
+            switch (node.kind) {
+                case 244 /* ImportDeclaration */:
+                    return visitImportDeclaration(node);
+                case 243 /* ImportEqualsDeclaration */:
+                    return visitImportEqualsDeclaration(node);
+                case 249 /* ExportAssignment */:
+                    return visitExportAssignment(node);
+                case 250 /* ExportDeclaration */:
+                    return visitExportDeclaration(node);
+                default:
+                    ts.Debug.fail("Unhandled ellided statement");
+            }
+        }
+        /**
+         * Specialized visitor that visits the immediate children of a namespace.
+         *
+         * @param node The node to visit.
+         */
+        function namespaceElementVisitor(node) {
+            return saveStateAndInvoke(node, namespaceElementVisitorWorker);
+        }
+        /**
+         * Specialized visitor that visits the immediate children of a namespace.
+         *
+         * @param node The node to visit.
+         */
+        function namespaceElementVisitorWorker(node) {
+            if (node.kind === 250 /* ExportDeclaration */ ||
+                node.kind === 244 /* ImportDeclaration */ ||
+                node.kind === 245 /* ImportClause */ ||
+                (node.kind === 243 /* ImportEqualsDeclaration */ &&
+                    node.moduleReference.kind === 254 /* ExternalModuleReference */)) {
+                // do not emit ES6 imports and exports since they are illegal inside a namespace
+                return undefined;
+            }
+            else if (node.transformFlags & 1 /* TypeScript */ || ts.hasModifier(node, 1 /* Export */)) {
+                // This node is explicitly marked as TypeScript, or is exported at the namespace
+                // level, so we should transform the node.
+                return visitTypeScript(node);
+            }
+            else if (node.transformFlags & 2 /* ContainsTypeScript */) {
+                // This node contains TypeScript, so we should visit its children.
+                return ts.visitEachChild(node, visitor, context);
+            }
+            return node;
+        }
+        /**
+         * Specialized visitor that visits the immediate children of a class with TypeScript syntax.
+         *
+         * @param node The node to visit.
+         */
+        function classElementVisitor(node) {
+            return saveStateAndInvoke(node, classElementVisitorWorker);
+        }
+        /**
+         * Specialized visitor that visits the immediate children of a class with TypeScript syntax.
+         *
+         * @param node The node to visit.
+         */
+        function classElementVisitorWorker(node) {
+            switch (node.kind) {
+                case 155 /* Constructor */:
+                    // TypeScript constructors are transformed in `visitClassDeclaration`.
+                    // We elide them here as `visitorWorker` checks transform flags, which could
+                    // erronously include an ES6 constructor without TypeScript syntax.
+                    return undefined;
+                case 152 /* PropertyDeclaration */:
+                case 160 /* IndexSignature */:
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                case 154 /* MethodDeclaration */:
+                    // Fallback to the default visit behavior.
+                    return visitorWorker(node);
+                case 212 /* SemicolonClassElement */:
+                    return node;
+                default:
+                    return ts.Debug.failBadSyntaxKind(node);
+            }
+        }
+        function modifierVisitor(node) {
+            if (ts.modifierToFlag(node.kind) & 2270 /* TypeScriptModifier */) {
+                return undefined;
+            }
+            else if (currentNamespace && node.kind === 84 /* ExportKeyword */) {
+                return undefined;
+            }
+            return node;
+        }
+        /**
+         * Branching visitor, visits a TypeScript syntax node.
+         *
+         * @param node The node to visit.
+         */
+        function visitTypeScript(node) {
+            if (ts.hasModifier(node, 2 /* Ambient */) && ts.isStatement(node)) {
+                // TypeScript ambient declarations are elided, but some comments may be preserved.
+                // See the implementation of `getLeadingComments` in comments.ts for more details.
+                return ts.createNotEmittedStatement(node);
+            }
+            switch (node.kind) {
+                case 84 /* ExportKeyword */:
+                case 79 /* DefaultKeyword */:
+                    // ES6 export and default modifiers are elided when inside a namespace.
+                    return currentNamespace ? undefined : node;
+                case 114 /* PublicKeyword */:
+                case 112 /* PrivateKeyword */:
+                case 113 /* ProtectedKeyword */:
+                case 117 /* AbstractKeyword */:
+                case 76 /* ConstKeyword */:
+                case 124 /* DeclareKeyword */:
+                case 132 /* ReadonlyKeyword */:
+                // TypeScript accessibility and readonly modifiers are elided.
+                case 167 /* ArrayType */:
+                case 168 /* TupleType */:
+                case 166 /* TypeLiteral */:
+                case 161 /* TypePredicate */:
+                case 148 /* TypeParameter */:
+                case 119 /* AnyKeyword */:
+                case 142 /* UnknownKeyword */:
+                case 122 /* BooleanKeyword */:
+                case 137 /* StringKeyword */:
+                case 134 /* NumberKeyword */:
+                case 131 /* NeverKeyword */:
+                case 105 /* VoidKeyword */:
+                case 138 /* SymbolKeyword */:
+                case 164 /* ConstructorType */:
+                case 163 /* FunctionType */:
+                case 165 /* TypeQuery */:
+                case 162 /* TypeReference */:
+                case 169 /* UnionType */:
+                case 170 /* IntersectionType */:
+                case 171 /* ConditionalType */:
+                case 173 /* ParenthesizedType */:
+                case 174 /* ThisType */:
+                case 175 /* TypeOperator */:
+                case 176 /* IndexedAccessType */:
+                case 177 /* MappedType */:
+                case 178 /* LiteralType */:
+                // TypeScript type nodes are elided.
+                case 160 /* IndexSignature */:
+                // TypeScript index signatures are elided.
+                case 150 /* Decorator */:
+                // TypeScript decorators are elided. They will be emitted as part of visitClassDeclaration.
+                case 237 /* TypeAliasDeclaration */:
+                    // TypeScript type-only declarations are elided.
+                    return undefined;
+                case 152 /* PropertyDeclaration */:
+                    // TypeScript property declarations are elided. However their names are still visited, and can potentially be retained if they could have sideeffects
+                    return visitPropertyDeclaration(node);
+                case 242 /* NamespaceExportDeclaration */:
+                    // TypeScript namespace export declarations are elided.
+                    return undefined;
+                case 155 /* Constructor */:
+                    return visitConstructor(node);
+                case 236 /* InterfaceDeclaration */:
+                    // TypeScript interfaces are elided, but some comments may be preserved.
+                    // See the implementation of `getLeadingComments` in comments.ts for more details.
+                    return ts.createNotEmittedStatement(node);
+                case 235 /* ClassDeclaration */:
+                    // This is a class declaration with TypeScript syntax extensions.
+                    //
+                    // TypeScript class syntax extensions include:
+                    // - decorators
+                    // - optional `implements` heritage clause
+                    // - parameter property assignments in the constructor
+                    // - property declarations
+                    // - index signatures
+                    // - method overload signatures
+                    return visitClassDeclaration(node);
+                case 205 /* ClassExpression */:
+                    // This is a class expression with TypeScript syntax extensions.
+                    //
+                    // TypeScript class syntax extensions include:
+                    // - decorators
+                    // - optional `implements` heritage clause
+                    // - parameter property assignments in the constructor
+                    // - property declarations
+                    // - index signatures
+                    // - method overload signatures
+                    return visitClassExpression(node);
+                case 268 /* HeritageClause */:
+                    // This is a heritage clause with TypeScript syntax extensions.
+                    //
+                    // TypeScript heritage clause extensions include:
+                    // - `implements` clause
+                    return visitHeritageClause(node);
+                case 207 /* ExpressionWithTypeArguments */:
+                    // TypeScript supports type arguments on an expression in an `extends` heritage clause.
+                    return visitExpressionWithTypeArguments(node);
+                case 154 /* MethodDeclaration */:
+                    // TypeScript method declarations may have decorators, modifiers
+                    // or type annotations.
+                    return visitMethodDeclaration(node);
+                case 156 /* GetAccessor */:
+                    // Get Accessors can have TypeScript modifiers, decorators, and type annotations.
+                    return visitGetAccessor(node);
+                case 157 /* SetAccessor */:
+                    // Set Accessors can have TypeScript modifiers and type annotations.
+                    return visitSetAccessor(node);
+                case 234 /* FunctionDeclaration */:
+                    // Typescript function declarations can have modifiers, decorators, and type annotations.
+                    return visitFunctionDeclaration(node);
+                case 192 /* FunctionExpression */:
+                    // TypeScript function expressions can have modifiers and type annotations.
+                    return visitFunctionExpression(node);
+                case 193 /* ArrowFunction */:
+                    // TypeScript arrow functions can have modifiers and type annotations.
+                    return visitArrowFunction(node);
+                case 149 /* Parameter */:
+                    // This is a parameter declaration with TypeScript syntax extensions.
+                    //
+                    // TypeScript parameter declaration syntax extensions include:
+                    // - decorators
+                    // - accessibility modifiers
+                    // - the question mark (?) token for optional parameters
+                    // - type annotations
+                    // - this parameters
+                    return visitParameter(node);
+                case 191 /* ParenthesizedExpression */:
+                    // ParenthesizedExpressions are TypeScript if their expression is a
+                    // TypeAssertion or AsExpression
+                    return visitParenthesizedExpression(node);
+                case 190 /* TypeAssertionExpression */:
+                case 208 /* AsExpression */:
+                    // TypeScript type assertions are removed, but their subtrees are preserved.
+                    return visitAssertionExpression(node);
+                case 187 /* CallExpression */:
+                    return visitCallExpression(node);
+                case 188 /* NewExpression */:
+                    return visitNewExpression(node);
+                case 189 /* TaggedTemplateExpression */:
+                    return visitTaggedTemplateExpression(node);
+                case 209 /* NonNullExpression */:
+                    // TypeScript non-null expressions are removed, but their subtrees are preserved.
+                    return visitNonNullExpression(node);
+                case 238 /* EnumDeclaration */:
+                    // TypeScript enum declarations do not exist in ES6 and must be rewritten.
+                    return visitEnumDeclaration(node);
+                case 214 /* VariableStatement */:
+                    // TypeScript namespace exports for variable statements must be transformed.
+                    return visitVariableStatement(node);
+                case 232 /* VariableDeclaration */:
+                    return visitVariableDeclaration(node);
+                case 239 /* ModuleDeclaration */:
+                    // TypeScript namespace declarations must be transformed.
+                    return visitModuleDeclaration(node);
+                case 243 /* ImportEqualsDeclaration */:
+                    // TypeScript namespace or external module import.
+                    return visitImportEqualsDeclaration(node);
+                default:
+                    return ts.Debug.failBadSyntaxKind(node);
+            }
+        }
+        function visitSourceFile(node) {
+            var alwaysStrict = ts.getStrictOptionValue(compilerOptions, "alwaysStrict") &&
+                !(ts.isExternalModule(node) && moduleKind >= ts.ModuleKind.ES2015) &&
+                !ts.isJsonSourceFile(node);
+            return ts.updateSourceFileNode(node, ts.visitLexicalEnvironment(node.statements, sourceElementVisitor, context, /*start*/ 0, alwaysStrict));
+        }
+        /**
+         * Tests whether we should emit a __decorate call for a class declaration.
+         */
+        function shouldEmitDecorateCallForClass(node) {
+            if (node.decorators && node.decorators.length > 0) {
+                return true;
+            }
+            var constructor = ts.getFirstConstructorWithBody(node);
+            if (constructor) {
+                return ts.forEach(constructor.parameters, shouldEmitDecorateCallForParameter);
+            }
+            return false;
+        }
+        /**
+         * Tests whether we should emit a __decorate call for a parameter declaration.
+         */
+        function shouldEmitDecorateCallForParameter(parameter) {
+            return parameter.decorators !== undefined && parameter.decorators.length > 0;
+        }
+        function getClassFacts(node, staticProperties) {
+            var facts = 0 /* None */;
+            if (ts.some(staticProperties))
+                facts |= 1 /* HasStaticInitializedProperties */;
+            var extendsClauseElement = ts.getClassExtendsHeritageClauseElement(node);
+            if (extendsClauseElement && ts.skipOuterExpressions(extendsClauseElement.expression).kind !== 95 /* NullKeyword */)
+                facts |= 64 /* IsDerivedClass */;
+            if (shouldEmitDecorateCallForClass(node))
+                facts |= 2 /* HasConstructorDecorators */;
+            if (ts.childIsDecorated(node))
+                facts |= 4 /* HasMemberDecorators */;
+            if (isExportOfNamespace(node))
+                facts |= 8 /* IsExportOfNamespace */;
+            else if (isDefaultExternalModuleExport(node))
+                facts |= 32 /* IsDefaultExternalExport */;
+            else if (isNamedExternalModuleExport(node))
+                facts |= 16 /* IsNamedExternalExport */;
+            if (languageVersion <= 1 /* ES5 */ && (facts & 7 /* MayNeedImmediatelyInvokedFunctionExpression */))
+                facts |= 128 /* UseImmediatelyInvokedFunctionExpression */;
+            return facts;
+        }
+        /**
+         * Transforms a class declaration with TypeScript syntax into compatible ES6.
+         *
+         * This function will only be called when one of the following conditions are met:
+         * - The class has decorators.
+         * - The class has property declarations with initializers.
+         * - The class contains a constructor that contains parameters with accessibility modifiers.
+         * - The class is an export in a TypeScript namespace.
+         *
+         * @param node The node to transform.
+         */
+        function visitClassDeclaration(node) {
+            var savedPendingExpressions = pendingExpressions;
+            pendingExpressions = undefined;
+            var staticProperties = getInitializedProperties(node, /*isStatic*/ true);
+            var facts = getClassFacts(node, staticProperties);
+            if (facts & 128 /* UseImmediatelyInvokedFunctionExpression */) {
+                context.startLexicalEnvironment();
+            }
+            var name = node.name || (facts & 5 /* NeedsName */ ? ts.getGeneratedNameForNode(node) : undefined);
+            var classStatement = facts & 2 /* HasConstructorDecorators */
+                ? createClassDeclarationHeadWithDecorators(node, name, facts)
+                : createClassDeclarationHeadWithoutDecorators(node, name, facts);
+            var statements = [classStatement];
+            // Write any pending expressions from elided or moved computed property names
+            if (ts.some(pendingExpressions)) {
+                statements.push(ts.createStatement(ts.inlineExpressions(pendingExpressions)));
+            }
+            pendingExpressions = savedPendingExpressions;
+            // Emit static property assignment. Because classDeclaration is lexically evaluated,
+            // it is safe to emit static property assignment after classDeclaration
+            // From ES6 specification:
+            //      HasLexicalDeclaration (N) : Determines if the argument identifier has a binding in this environment record that was created using
+            //                                  a lexical declaration such as a LexicalDeclaration or a ClassDeclaration.
+            if (facts & 1 /* HasStaticInitializedProperties */) {
+                addInitializedPropertyStatements(statements, staticProperties, facts & 128 /* UseImmediatelyInvokedFunctionExpression */ ? ts.getInternalName(node) : ts.getLocalName(node));
+            }
+            // Write any decorators of the node.
+            addClassElementDecorationStatements(statements, node, /*isStatic*/ false);
+            addClassElementDecorationStatements(statements, node, /*isStatic*/ true);
+            addConstructorDecorationStatement(statements, node);
+            if (facts & 128 /* UseImmediatelyInvokedFunctionExpression */) {
+                // When we emit a TypeScript class down to ES5, we must wrap it in an IIFE so that the
+                // 'es2015' transformer can properly nest static initializers and decorators. The result
+                // looks something like:
+                //
+                //  var C = function () {
+                //      class C {
+                //      }
+                //      C.static_prop = 1;
+                //      return C;
+                //  }();
+                //
+                var closingBraceLocation = ts.createTokenRange(ts.skipTrivia(currentSourceFile.text, node.members.end), 18 /* CloseBraceToken */);
+                var localName = ts.getInternalName(node);
+                // The following partially-emitted expression exists purely to align our sourcemap
+                // emit with the original emitter.
+                var outer = ts.createPartiallyEmittedExpression(localName);
+                outer.end = closingBraceLocation.end;
+                ts.setEmitFlags(outer, 1536 /* NoComments */);
+                var statement = ts.createReturn(outer);
+                statement.pos = closingBraceLocation.pos;
+                ts.setEmitFlags(statement, 1536 /* NoComments */ | 384 /* NoTokenSourceMaps */);
+                statements.push(statement);
+                ts.prependStatements(statements, context.endLexicalEnvironment());
+                var iife = ts.createImmediatelyInvokedArrowFunction(statements);
+                ts.setEmitFlags(iife, 33554432 /* TypeScriptClassWrapper */);
+                var varStatement = ts.createVariableStatement(
+                /*modifiers*/ undefined, ts.createVariableDeclarationList([
+                    ts.createVariableDeclaration(ts.getLocalName(node, /*allowComments*/ false, /*allowSourceMaps*/ false), 
+                    /*type*/ undefined, iife)
+                ]));
+                ts.setOriginalNode(varStatement, node);
+                ts.setCommentRange(varStatement, node);
+                ts.setSourceMapRange(varStatement, ts.moveRangePastDecorators(node));
+                ts.startOnNewLine(varStatement);
+                statements = [varStatement];
+            }
+            // If the class is exported as part of a TypeScript namespace, emit the namespace export.
+            // Otherwise, if the class was exported at the top level and was decorated, emit an export
+            // declaration or export default for the class.
+            if (facts & 8 /* IsExportOfNamespace */) {
+                addExportMemberAssignment(statements, node);
+            }
+            else if (facts & 128 /* UseImmediatelyInvokedFunctionExpression */ || facts & 2 /* HasConstructorDecorators */) {
+                if (facts & 32 /* IsDefaultExternalExport */) {
+                    statements.push(ts.createExportDefault(ts.getLocalName(node, /*allowComments*/ false, /*allowSourceMaps*/ true)));
+                }
+                else if (facts & 16 /* IsNamedExternalExport */) {
+                    statements.push(ts.createExternalModuleExport(ts.getLocalName(node, /*allowComments*/ false, /*allowSourceMaps*/ true)));
+                }
+            }
+            if (statements.length > 1) {
+                // Add a DeclarationMarker as a marker for the end of the declaration
+                statements.push(ts.createEndOfDeclarationMarker(node));
+                ts.setEmitFlags(classStatement, ts.getEmitFlags(classStatement) | 4194304 /* HasEndOfDeclarationMarker */);
+            }
+            return ts.singleOrMany(statements);
+        }
+        /**
+         * Transforms a non-decorated class declaration and appends the resulting statements.
+         *
+         * @param node A ClassDeclaration node.
+         * @param name The name of the class.
+         * @param facts Precomputed facts about the class.
+         */
+        function createClassDeclarationHeadWithoutDecorators(node, name, facts) {
+            //  ${modifiers} class ${name} ${heritageClauses} {
+            //      ${members}
+            //  }
+            // we do not emit modifiers on the declaration if we are emitting an IIFE
+            var modifiers = !(facts & 128 /* UseImmediatelyInvokedFunctionExpression */)
+                ? ts.visitNodes(node.modifiers, modifierVisitor, ts.isModifier)
+                : undefined;
+            var classDeclaration = ts.createClassDeclaration(
+            /*decorators*/ undefined, modifiers, name, 
+            /*typeParameters*/ undefined, ts.visitNodes(node.heritageClauses, visitor, ts.isHeritageClause), transformClassMembers(node, (facts & 64 /* IsDerivedClass */) !== 0));
+            // To better align with the old emitter, we should not emit a trailing source map
+            // entry if the class has static properties.
+            var emitFlags = ts.getEmitFlags(node);
+            if (facts & 1 /* HasStaticInitializedProperties */) {
+                emitFlags |= 32 /* NoTrailingSourceMap */;
+            }
+            ts.setTextRange(classDeclaration, node);
+            ts.setOriginalNode(classDeclaration, node);
+            ts.setEmitFlags(classDeclaration, emitFlags);
+            return classDeclaration;
+        }
+        /**
+         * Transforms a decorated class declaration and appends the resulting statements. If
+         * the class requires an alias to avoid issues with double-binding, the alias is returned.
+         */
+        function createClassDeclarationHeadWithDecorators(node, name, facts) {
+            // When we emit an ES6 class that has a class decorator, we must tailor the
+            // emit to certain specific cases.
+            //
+            // In the simplest case, we emit the class declaration as a let declaration, and
+            // evaluate decorators after the close of the class body:
+            //
+            //  [Example 1]
+            //  ---------------------------------------------------------------------
+            //  TypeScript                      | Javascript
+            //  ---------------------------------------------------------------------
+            //  @dec                            | let C = class C {
+            //  class C {                       | }
+            //  }                               | C = __decorate([dec], C);
+            //  ---------------------------------------------------------------------
+            //  @dec                            | let C = class C {
+            //  export class C {                | }
+            //  }                               | C = __decorate([dec], C);
+            //                                  | export { C };
+            //  ---------------------------------------------------------------------
+            //
+            // If a class declaration contains a reference to itself *inside* of the class body,
+            // this introduces two bindings to the class: One outside of the class body, and one
+            // inside of the class body. If we apply decorators as in [Example 1] above, there
+            // is the possibility that the decorator `dec` will return a new value for the
+            // constructor, which would result in the binding inside of the class no longer
+            // pointing to the same reference as the binding outside of the class.
+            //
+            // As a result, we must instead rewrite all references to the class *inside* of the
+            // class body to instead point to a local temporary alias for the class:
+            //
+            //  [Example 2]
+            //  ---------------------------------------------------------------------
+            //  TypeScript                      | Javascript
+            //  ---------------------------------------------------------------------
+            //  @dec                            | let C = C_1 = class C {
+            //  class C {                       |   static x() { return C_1.y; }
+            //    static x() { return C.y; }    | }
+            //    static y = 1;                 | C.y = 1;
+            //  }                               | C = C_1 = __decorate([dec], C);
+            //                                  | var C_1;
+            //  ---------------------------------------------------------------------
+            //  @dec                            | let C = class C {
+            //  export class C {                |   static x() { return C_1.y; }
+            //    static x() { return C.y; }    | }
+            //    static y = 1;                 | C.y = 1;
+            //  }                               | C = C_1 = __decorate([dec], C);
+            //                                  | export { C };
+            //                                  | var C_1;
+            //  ---------------------------------------------------------------------
+            //
+            // If a class declaration is the default export of a module, we instead emit
+            // the export after the decorated declaration:
+            //
+            //  [Example 3]
+            //  ---------------------------------------------------------------------
+            //  TypeScript                      | Javascript
+            //  ---------------------------------------------------------------------
+            //  @dec                            | let default_1 = class {
+            //  export default class {          | }
+            //  }                               | default_1 = __decorate([dec], default_1);
+            //                                  | export default default_1;
+            //  ---------------------------------------------------------------------
+            //  @dec                            | let C = class C {
+            //  export default class C {        | }
+            //  }                               | C = __decorate([dec], C);
+            //                                  | export default C;
+            //  ---------------------------------------------------------------------
+            //
+            // If the class declaration is the default export and a reference to itself
+            // inside of the class body, we must emit both an alias for the class *and*
+            // move the export after the declaration:
+            //
+            //  [Example 4]
+            //  ---------------------------------------------------------------------
+            //  TypeScript                      | Javascript
+            //  ---------------------------------------------------------------------
+            //  @dec                            | let C = class C {
+            //  export default class C {        |   static x() { return C_1.y; }
+            //    static x() { return C.y; }    | }
+            //    static y = 1;                 | C.y = 1;
+            //  }                               | C = C_1 = __decorate([dec], C);
+            //                                  | export default C;
+            //                                  | var C_1;
+            //  ---------------------------------------------------------------------
+            //
+            var location = ts.moveRangePastDecorators(node);
+            var classAlias = getClassAliasIfNeeded(node);
+            var declName = ts.getLocalName(node, /*allowComments*/ false, /*allowSourceMaps*/ true);
+            //  ... = class ${name} ${heritageClauses} {
+            //      ${members}
+            //  }
+            var heritageClauses = ts.visitNodes(node.heritageClauses, visitor, ts.isHeritageClause);
+            var members = transformClassMembers(node, (facts & 64 /* IsDerivedClass */) !== 0);
+            var classExpression = ts.createClassExpression(/*modifiers*/ undefined, name, /*typeParameters*/ undefined, heritageClauses, members);
+            ts.setOriginalNode(classExpression, node);
+            ts.setTextRange(classExpression, location);
+            //  let ${name} = ${classExpression} where name is either declaredName if the class doesn't contain self-reference
+            //                                         or decoratedClassAlias if the class contain self-reference.
+            var statement = ts.createVariableStatement(
+            /*modifiers*/ undefined, ts.createVariableDeclarationList([
+                ts.createVariableDeclaration(declName, 
+                /*type*/ undefined, classAlias ? ts.createAssignment(classAlias, classExpression) : classExpression)
+            ], 1 /* Let */));
+            ts.setOriginalNode(statement, node);
+            ts.setTextRange(statement, location);
+            ts.setCommentRange(statement, node);
+            return statement;
+        }
+        /**
+         * Transforms a class expression with TypeScript syntax into compatible ES6.
+         *
+         * This function will only be called when one of the following conditions are met:
+         * - The class has property declarations with initializers.
+         * - The class contains a constructor that contains parameters with accessibility modifiers.
+         *
+         * @param node The node to transform.
+         */
+        function visitClassExpression(node) {
+            var savedPendingExpressions = pendingExpressions;
+            pendingExpressions = undefined;
+            var staticProperties = getInitializedProperties(node, /*isStatic*/ true);
+            var heritageClauses = ts.visitNodes(node.heritageClauses, visitor, ts.isHeritageClause);
+            var members = transformClassMembers(node, ts.some(heritageClauses, function (c) { return c.token === 85 /* ExtendsKeyword */; }));
+            var classExpression = ts.createClassExpression(
+            /*modifiers*/ undefined, node.name, 
+            /*typeParameters*/ undefined, heritageClauses, members);
+            ts.setOriginalNode(classExpression, node);
+            ts.setTextRange(classExpression, node);
+            if (ts.some(staticProperties) || ts.some(pendingExpressions)) {
+                var expressions = [];
+                var isClassWithConstructorReference = resolver.getNodeCheckFlags(node) & 8388608 /* ClassWithConstructorReference */;
+                var temp = ts.createTempVariable(hoistVariableDeclaration, !!isClassWithConstructorReference);
+                if (isClassWithConstructorReference) {
+                    // record an alias as the class name is not in scope for statics.
+                    enableSubstitutionForClassAliases();
+                    var alias = ts.getSynthesizedClone(temp);
+                    alias.autoGenerateFlags &= ~8 /* ReservedInNestedScopes */;
+                    classAliases[ts.getOriginalNodeId(node)] = alias;
+                }
+                // To preserve the behavior of the old emitter, we explicitly indent
+                // the body of a class with static initializers.
+                ts.setEmitFlags(classExpression, 65536 /* Indented */ | ts.getEmitFlags(classExpression));
+                expressions.push(ts.startOnNewLine(ts.createAssignment(temp, classExpression)));
+                // Add any pending expressions leftover from elided or relocated computed property names
+                ts.addRange(expressions, ts.map(pendingExpressions, ts.startOnNewLine));
+                pendingExpressions = savedPendingExpressions;
+                ts.addRange(expressions, generateInitializedPropertyExpressions(staticProperties, temp));
+                expressions.push(ts.startOnNewLine(temp));
+                return ts.inlineExpressions(expressions);
+            }
+            pendingExpressions = savedPendingExpressions;
+            return classExpression;
+        }
+        /**
+         * Transforms the members of a class.
+         *
+         * @param node The current class.
+         * @param isDerivedClass A value indicating whether the class has an extends clause that does not extend 'null'.
+         */
+        function transformClassMembers(node, isDerivedClass) {
+            var members = [];
+            var constructor = transformConstructor(node, isDerivedClass);
+            if (constructor) {
+                members.push(constructor);
+            }
+            ts.addRange(members, ts.visitNodes(node.members, classElementVisitor, ts.isClassElement));
+            return ts.setTextRange(ts.createNodeArray(members), /*location*/ node.members);
+        }
+        /**
+         * Transforms (or creates) a constructor for a class.
+         *
+         * @param node The current class.
+         * @param isDerivedClass A value indicating whether the class has an extends clause that does not extend 'null'.
+         */
+        function transformConstructor(node, isDerivedClass) {
+            // Check if we have property assignment inside class declaration.
+            // If there is a property assignment, we need to emit constructor whether users define it or not
+            // If there is no property assignment, we can omit constructor if users do not define it
+            var hasInstancePropertyWithInitializer = ts.forEach(node.members, isInstanceInitializedProperty);
+            var hasParameterPropertyAssignments = node.transformFlags & 262144 /* ContainsParameterPropertyAssignments */;
+            var constructor = ts.getFirstConstructorWithBody(node);
+            // If the class does not contain nodes that require a synthesized constructor,
+            // accept the current constructor if it exists.
+            if (!hasInstancePropertyWithInitializer && !hasParameterPropertyAssignments) {
+                return ts.visitEachChild(constructor, visitor, context);
+            }
+            var parameters = transformConstructorParameters(constructor);
+            var body = transformConstructorBody(node, constructor, isDerivedClass);
+            //  constructor(${parameters}) {
+            //      ${body}
+            //  }
+            return ts.startOnNewLine(ts.setOriginalNode(ts.setTextRange(ts.createConstructor(
+            /*decorators*/ undefined, 
+            /*modifiers*/ undefined, parameters, body), constructor || node), constructor));
+        }
+        /**
+         * Transforms (or creates) the parameters for the constructor of a class with
+         * parameter property assignments or instance property initializers.
+         *
+         * @param constructor The constructor declaration.
+         */
+        function transformConstructorParameters(constructor) {
+            // The ES2015 spec specifies in 14.5.14. Runtime Semantics: ClassDefinitionEvaluation:
+            // If constructor is empty, then
+            //     If ClassHeritag_eopt is present and protoParent is not null, then
+            //          Let constructor be the result of parsing the source text
+            //              constructor(...args) { super (...args);}
+            //          using the syntactic grammar with the goal symbol MethodDefinition[~Yield].
+            //      Else,
+            //           Let constructor be the result of parsing the source text
+            //               constructor( ){ }
+            //           using the syntactic grammar with the goal symbol MethodDefinition[~Yield].
+            //
+            // While we could emit the '...args' rest parameter, certain later tools in the pipeline might
+            // downlevel the '...args' portion less efficiently by naively copying the contents of 'arguments' to an array.
+            // Instead, we'll avoid using a rest parameter and spread into the super call as
+            // 'super(...arguments)' instead of 'super(...args)', as you can see in "transformConstructorBody".
+            return ts.visitParameterList(constructor && constructor.parameters, visitor, context)
+                || [];
+        }
+        /**
+         * Transforms (or creates) a constructor body for a class with parameter property
+         * assignments or instance property initializers.
+         *
+         * @param node The current class.
+         * @param constructor The current class constructor.
+         * @param isDerivedClass A value indicating whether the class has an extends clause that does not extend 'null'.
+         */
+        function transformConstructorBody(node, constructor, isDerivedClass) {
+            var statements = [];
+            var indexOfFirstStatement = 0;
+            resumeLexicalEnvironment();
+            if (constructor) {
+                indexOfFirstStatement = addPrologueDirectivesAndInitialSuperCall(constructor, statements);
+                // Add parameters with property assignments. Transforms this:
+                //
+                //  constructor (public x, public y) {
+                //  }
+                //
+                // Into this:
+                //
+                //  constructor (x, y) {
+                //      this.x = x;
+                //      this.y = y;
+                //  }
+                //
+                var propertyAssignments = getParametersWithPropertyAssignments(constructor);
+                ts.addRange(statements, ts.map(propertyAssignments, transformParameterWithPropertyAssignment));
+            }
+            else if (isDerivedClass) {
+                // Add a synthetic `super` call:
+                //
+                //  super(...arguments);
+                //
+                statements.push(ts.createStatement(ts.createCall(ts.createSuper(), 
+                /*typeArguments*/ undefined, [ts.createSpread(ts.createIdentifier("arguments"))])));
+            }
+            // Add the property initializers. Transforms this:
+            //
+            //  public x = 1;
+            //
+            // Into this:
+            //
+            //  constructor() {
+            //      this.x = 1;
+            //  }
+            //
+            var properties = getInitializedProperties(node, /*isStatic*/ false);
+            addInitializedPropertyStatements(statements, properties, ts.createThis());
+            if (constructor) {
+                // The class already had a constructor, so we should add the existing statements, skipping the initial super call.
+                ts.addRange(statements, ts.visitNodes(constructor.body.statements, visitor, ts.isStatement, indexOfFirstStatement));
+            }
+            // End the lexical environment.
+            statements = ts.mergeLexicalEnvironment(statements, endLexicalEnvironment());
+            return ts.setTextRange(ts.createBlock(ts.setTextRange(ts.createNodeArray(statements), 
+            /*location*/ constructor ? constructor.body.statements : node.members), 
+            /*multiLine*/ true), 
+            /*location*/ constructor ? constructor.body : undefined);
+        }
+        /**
+         * Adds super call and preceding prologue directives into the list of statements.
+         *
+         * @param ctor The constructor node.
+         * @returns index of the statement that follows super call
+         */
+        function addPrologueDirectivesAndInitialSuperCall(ctor, result) {
+            if (ctor.body) {
+                var statements = ctor.body.statements;
+                // add prologue directives to the list (if any)
+                var index = ts.addPrologue(result, statements, /*ensureUseStrict*/ false, visitor);
+                if (index === statements.length) {
+                    // list contains nothing but prologue directives (or empty) - exit
+                    return index;
+                }
+                var statement = statements[index];
+                if (statement.kind === 216 /* ExpressionStatement */ && ts.isSuperCall(statement.expression)) {
+                    result.push(ts.visitNode(statement, visitor, ts.isStatement));
+                    return index + 1;
+                }
+                return index;
+            }
+            return 0;
+        }
+        /**
+         * Gets all parameters of a constructor that should be transformed into property assignments.
+         *
+         * @param node The constructor node.
+         */
+        function getParametersWithPropertyAssignments(node) {
+            return ts.filter(node.parameters, isParameterWithPropertyAssignment);
+        }
+        /**
+         * Determines whether a parameter should be transformed into a property assignment.
+         *
+         * @param parameter The parameter node.
+         */
+        function isParameterWithPropertyAssignment(parameter) {
+            return ts.hasModifier(parameter, 92 /* ParameterPropertyModifier */)
+                && ts.isIdentifier(parameter.name);
+        }
+        /**
+         * Transforms a parameter into a property assignment statement.
+         *
+         * @param node The parameter declaration.
+         */
+        function transformParameterWithPropertyAssignment(node) {
+            ts.Debug.assert(ts.isIdentifier(node.name));
+            var name = node.name;
+            var propertyName = ts.getMutableClone(name);
+            ts.setEmitFlags(propertyName, 1536 /* NoComments */ | 48 /* NoSourceMap */);
+            var localName = ts.getMutableClone(name);
+            ts.setEmitFlags(localName, 1536 /* NoComments */);
+            return ts.startOnNewLine(ts.setEmitFlags(ts.setTextRange(ts.createStatement(ts.createAssignment(ts.setTextRange(ts.createPropertyAccess(ts.createThis(), propertyName), node.name), localName)), ts.moveRangePos(node, -1)), 1536 /* NoComments */));
+        }
+        /**
+         * Gets all property declarations with initializers on either the static or instance side of a class.
+         *
+         * @param node The class node.
+         * @param isStatic A value indicating whether to get properties from the static or instance side of the class.
+         */
+        function getInitializedProperties(node, isStatic) {
+            return ts.filter(node.members, isStatic ? isStaticInitializedProperty : isInstanceInitializedProperty);
+        }
+        /**
+         * Gets a value indicating whether a class element is a static property declaration with an initializer.
+         *
+         * @param member The class element node.
+         */
+        function isStaticInitializedProperty(member) {
+            return isInitializedProperty(member, /*isStatic*/ true);
+        }
+        /**
+         * Gets a value indicating whether a class element is an instance property declaration with an initializer.
+         *
+         * @param member The class element node.
+         */
+        function isInstanceInitializedProperty(member) {
+            return isInitializedProperty(member, /*isStatic*/ false);
+        }
+        /**
+         * Gets a value indicating whether a class element is either a static or an instance property declaration with an initializer.
+         *
+         * @param member The class element node.
+         * @param isStatic A value indicating whether the member should be a static or instance member.
+         */
+        function isInitializedProperty(member, isStatic) {
+            return member.kind === 152 /* PropertyDeclaration */
+                && isStatic === ts.hasModifier(member, 32 /* Static */)
+                && member.initializer !== undefined;
+        }
+        /**
+         * Generates assignment statements for property initializers.
+         *
+         * @param properties An array of property declarations to transform.
+         * @param receiver The receiver on which each property should be assigned.
+         */
+        function addInitializedPropertyStatements(statements, properties, receiver) {
+            for (var _i = 0, properties_10 = properties; _i < properties_10.length; _i++) {
+                var property = properties_10[_i];
+                var statement = ts.createStatement(transformInitializedProperty(property, receiver));
+                ts.setSourceMapRange(statement, ts.moveRangePastModifiers(property));
+                ts.setCommentRange(statement, property);
+                statements.push(statement);
+            }
+        }
+        /**
+         * Generates assignment expressions for property initializers.
+         *
+         * @param properties An array of property declarations to transform.
+         * @param receiver The receiver on which each property should be assigned.
+         */
+        function generateInitializedPropertyExpressions(properties, receiver) {
+            var expressions = [];
+            for (var _i = 0, properties_11 = properties; _i < properties_11.length; _i++) {
+                var property = properties_11[_i];
+                var expression = transformInitializedProperty(property, receiver);
+                ts.startOnNewLine(expression);
+                ts.setSourceMapRange(expression, ts.moveRangePastModifiers(property));
+                ts.setCommentRange(expression, property);
+                expressions.push(expression);
+            }
+            return expressions;
+        }
+        /**
+         * Transforms a property initializer into an assignment statement.
+         *
+         * @param property The property declaration.
+         * @param receiver The object receiving the property assignment.
+         */
+        function transformInitializedProperty(property, receiver) {
+            // We generate a name here in order to reuse the value cached by the relocated computed name expression (which uses the same generated name)
+            var propertyName = ts.isComputedPropertyName(property.name) && !isSimpleInlineableExpression(property.name.expression)
+                ? ts.updateComputedPropertyName(property.name, ts.getGeneratedNameForNode(property.name))
+                : property.name;
+            var initializer = ts.visitNode(property.initializer, visitor, ts.isExpression);
+            var memberAccess = ts.createMemberAccessForPropertyName(receiver, propertyName, /*location*/ propertyName);
+            return ts.createAssignment(memberAccess, initializer);
+        }
+        /**
+         * Gets either the static or instance members of a class that are decorated, or have
+         * parameters that are decorated.
+         *
+         * @param node The class containing the member.
+         * @param isStatic A value indicating whether to retrieve static or instance members of
+         *                 the class.
+         */
+        function getDecoratedClassElements(node, isStatic) {
+            return ts.filter(node.members, isStatic ? function (m) { return isStaticDecoratedClassElement(m, node); } : function (m) { return isInstanceDecoratedClassElement(m, node); });
+        }
+        /**
+         * Determines whether a class member is a static member of a class that is decorated, or
+         * has parameters that are decorated.
+         *
+         * @param member The class member.
+         */
+        function isStaticDecoratedClassElement(member, parent) {
+            return isDecoratedClassElement(member, /*isStatic*/ true, parent);
+        }
+        /**
+         * Determines whether a class member is an instance member of a class that is decorated,
+         * or has parameters that are decorated.
+         *
+         * @param member The class member.
+         */
+        function isInstanceDecoratedClassElement(member, parent) {
+            return isDecoratedClassElement(member, /*isStatic*/ false, parent);
+        }
+        /**
+         * Determines whether a class member is either a static or an instance member of a class
+         * that is decorated, or has parameters that are decorated.
+         *
+         * @param member The class member.
+         */
+        function isDecoratedClassElement(member, isStatic, parent) {
+            return ts.nodeOrChildIsDecorated(member, parent)
+                && isStatic === ts.hasModifier(member, 32 /* Static */);
+        }
+        /**
+         * Gets an array of arrays of decorators for the parameters of a function-like node.
+         * The offset into the result array should correspond to the offset of the parameter.
+         *
+         * @param node The function-like node.
+         */
+        function getDecoratorsOfParameters(node) {
+            var decorators;
+            if (node) {
+                var parameters = node.parameters;
+                for (var i = 0; i < parameters.length; i++) {
+                    var parameter = parameters[i];
+                    if (decorators || parameter.decorators) {
+                        if (!decorators) {
+                            decorators = new Array(parameters.length);
+                        }
+                        decorators[i] = parameter.decorators;
+                    }
+                }
+            }
+            return decorators;
+        }
+        /**
+         * Gets an AllDecorators object containing the decorators for the class and the decorators for the
+         * parameters of the constructor of the class.
+         *
+         * @param node The class node.
+         */
+        function getAllDecoratorsOfConstructor(node) {
+            var decorators = node.decorators;
+            var parameters = getDecoratorsOfParameters(ts.getFirstConstructorWithBody(node));
+            if (!decorators && !parameters) {
+                return undefined;
+            }
+            return {
+                decorators: decorators,
+                parameters: parameters
+            };
+        }
+        /**
+         * Gets an AllDecorators object containing the decorators for the member and its parameters.
+         *
+         * @param node The class node that contains the member.
+         * @param member The class member.
+         */
+        function getAllDecoratorsOfClassElement(node, member) {
+            switch (member.kind) {
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                    return getAllDecoratorsOfAccessors(node, member);
+                case 154 /* MethodDeclaration */:
+                    return getAllDecoratorsOfMethod(member);
+                case 152 /* PropertyDeclaration */:
+                    return getAllDecoratorsOfProperty(member);
+                default:
+                    return undefined;
+            }
+        }
+        /**
+         * Gets an AllDecorators object containing the decorators for the accessor and its parameters.
+         *
+         * @param node The class node that contains the accessor.
+         * @param accessor The class accessor member.
+         */
+        function getAllDecoratorsOfAccessors(node, accessor) {
+            if (!accessor.body) {
+                return undefined;
+            }
+            var _a = ts.getAllAccessorDeclarations(node.members, accessor), firstAccessor = _a.firstAccessor, secondAccessor = _a.secondAccessor, setAccessor = _a.setAccessor;
+            var firstAccessorWithDecorators = firstAccessor.decorators ? firstAccessor : secondAccessor && secondAccessor.decorators ? secondAccessor : undefined;
+            if (!firstAccessorWithDecorators || accessor !== firstAccessorWithDecorators) {
+                return undefined;
+            }
+            var decorators = firstAccessorWithDecorators.decorators;
+            var parameters = getDecoratorsOfParameters(setAccessor);
+            if (!decorators && !parameters) {
+                return undefined;
+            }
+            return { decorators: decorators, parameters: parameters };
+        }
+        /**
+         * Gets an AllDecorators object containing the decorators for the method and its parameters.
+         *
+         * @param method The class method member.
+         */
+        function getAllDecoratorsOfMethod(method) {
+            if (!method.body) {
+                return undefined;
+            }
+            var decorators = method.decorators;
+            var parameters = getDecoratorsOfParameters(method);
+            if (!decorators && !parameters) {
+                return undefined;
+            }
+            return { decorators: decorators, parameters: parameters };
+        }
+        /**
+         * Gets an AllDecorators object containing the decorators for the property.
+         *
+         * @param property The class property member.
+         */
+        function getAllDecoratorsOfProperty(property) {
+            var decorators = property.decorators;
+            if (!decorators) {
+                return undefined;
+            }
+            return { decorators: decorators };
+        }
+        /**
+         * Transforms all of the decorators for a declaration into an array of expressions.
+         *
+         * @param node The declaration node.
+         * @param allDecorators An object containing all of the decorators for the declaration.
+         */
+        function transformAllDecoratorsOfDeclaration(node, container, allDecorators) {
+            if (!allDecorators) {
+                return undefined;
+            }
+            var decoratorExpressions = [];
+            ts.addRange(decoratorExpressions, ts.map(allDecorators.decorators, transformDecorator));
+            ts.addRange(decoratorExpressions, ts.flatMap(allDecorators.parameters, transformDecoratorsOfParameter));
+            addTypeMetadata(node, container, decoratorExpressions);
+            return decoratorExpressions;
+        }
+        /**
+         * Generates statements used to apply decorators to either the static or instance members
+         * of a class.
+         *
+         * @param node The class node.
+         * @param isStatic A value indicating whether to generate statements for static or
+         *                 instance members.
+         */
+        function addClassElementDecorationStatements(statements, node, isStatic) {
+            ts.addRange(statements, ts.map(generateClassElementDecorationExpressions(node, isStatic), expressionToStatement));
+        }
+        /**
+         * Generates expressions used to apply decorators to either the static or instance members
+         * of a class.
+         *
+         * @param node The class node.
+         * @param isStatic A value indicating whether to generate expressions for static or
+         *                 instance members.
+         */
+        function generateClassElementDecorationExpressions(node, isStatic) {
+            var members = getDecoratedClassElements(node, isStatic);
+            var expressions;
+            for (var _i = 0, members_5 = members; _i < members_5.length; _i++) {
+                var member = members_5[_i];
+                var expression = generateClassElementDecorationExpression(node, member);
+                if (expression) {
+                    if (!expressions) {
+                        expressions = [expression];
+                    }
+                    else {
+                        expressions.push(expression);
+                    }
+                }
+            }
+            return expressions;
+        }
+        /**
+         * Generates an expression used to evaluate class element decorators at runtime.
+         *
+         * @param node The class node that contains the member.
+         * @param member The class member.
+         */
+        function generateClassElementDecorationExpression(node, member) {
+            var allDecorators = getAllDecoratorsOfClassElement(node, member);
+            var decoratorExpressions = transformAllDecoratorsOfDeclaration(member, node, allDecorators);
+            if (!decoratorExpressions) {
+                return undefined;
+            }
+            // Emit the call to __decorate. Given the following:
+            //
+            //   class C {
+            //     @dec method(@dec2 x) {}
+            //     @dec get accessor() {}
+            //     @dec prop;
+            //   }
+            //
+            // The emit for a method is:
+            //
+            //   __decorate([
+            //       dec,
+            //       __param(0, dec2),
+            //       __metadata("design:type", Function),
+            //       __metadata("design:paramtypes", [Object]),
+            //       __metadata("design:returntype", void 0)
+            //   ], C.prototype, "method", null);
+            //
+            // The emit for an accessor is:
+            //
+            //   __decorate([
+            //       dec
+            //   ], C.prototype, "accessor", null);
+            //
+            // The emit for a property is:
+            //
+            //   __decorate([
+            //       dec
+            //   ], C.prototype, "prop");
+            //
+            var prefix = getClassMemberPrefix(node, member);
+            var memberName = getExpressionForPropertyName(member, /*generateNameForComputedPropertyName*/ true);
+            var descriptor = languageVersion > 0 /* ES3 */
+                ? member.kind === 152 /* PropertyDeclaration */
+                    // We emit `void 0` here to indicate to `__decorate` that it can invoke `Object.defineProperty` directly, but that it
+                    // should not invoke `Object.getOwnPropertyDescriptor`.
+                    ? ts.createVoidZero()
+                    // We emit `null` here to indicate to `__decorate` that it can invoke `Object.getOwnPropertyDescriptor` directly.
+                    // We have this extra argument here so that we can inject an explicit property descriptor at a later date.
+                    : ts.createNull()
+                : undefined;
+            var helper = createDecorateHelper(context, decoratorExpressions, prefix, memberName, descriptor, ts.moveRangePastDecorators(member));
+            ts.setEmitFlags(helper, 1536 /* NoComments */);
+            return helper;
+        }
+        /**
+         * Generates a __decorate helper call for a class constructor.
+         *
+         * @param node The class node.
+         */
+        function addConstructorDecorationStatement(statements, node) {
+            var expression = generateConstructorDecorationExpression(node);
+            if (expression) {
+                statements.push(ts.setOriginalNode(ts.createStatement(expression), node));
+            }
+        }
+        /**
+         * Generates a __decorate helper call for a class constructor.
+         *
+         * @param node The class node.
+         */
+        function generateConstructorDecorationExpression(node) {
+            var allDecorators = getAllDecoratorsOfConstructor(node);
+            var decoratorExpressions = transformAllDecoratorsOfDeclaration(node, node, allDecorators);
+            if (!decoratorExpressions) {
+                return undefined;
+            }
+            var classAlias = classAliases && classAliases[ts.getOriginalNodeId(node)];
+            var localName = ts.getLocalName(node, /*allowComments*/ false, /*allowSourceMaps*/ true);
+            var decorate = createDecorateHelper(context, decoratorExpressions, localName);
+            var expression = ts.createAssignment(localName, classAlias ? ts.createAssignment(classAlias, decorate) : decorate);
+            ts.setEmitFlags(expression, 1536 /* NoComments */);
+            ts.setSourceMapRange(expression, ts.moveRangePastDecorators(node));
+            return expression;
+        }
+        /**
+         * Transforms a decorator into an expression.
+         *
+         * @param decorator The decorator node.
+         */
+        function transformDecorator(decorator) {
+            return ts.visitNode(decorator.expression, visitor, ts.isExpression);
+        }
+        /**
+         * Transforms the decorators of a parameter.
+         *
+         * @param decorators The decorators for the parameter at the provided offset.
+         * @param parameterOffset The offset of the parameter.
+         */
+        function transformDecoratorsOfParameter(decorators, parameterOffset) {
+            var expressions;
+            if (decorators) {
+                expressions = [];
+                for (var _i = 0, decorators_1 = decorators; _i < decorators_1.length; _i++) {
+                    var decorator = decorators_1[_i];
+                    var helper = createParamHelper(context, transformDecorator(decorator), parameterOffset, 
+                    /*location*/ decorator.expression);
+                    ts.setEmitFlags(helper, 1536 /* NoComments */);
+                    expressions.push(helper);
+                }
+            }
+            return expressions;
+        }
+        /**
+         * Adds optional type metadata for a declaration.
+         *
+         * @param node The declaration node.
+         * @param decoratorExpressions The destination array to which to add new decorator expressions.
+         */
+        function addTypeMetadata(node, container, decoratorExpressions) {
+            if (USE_NEW_TYPE_METADATA_FORMAT) {
+                addNewTypeMetadata(node, container, decoratorExpressions);
+            }
+            else {
+                addOldTypeMetadata(node, container, decoratorExpressions);
+            }
+        }
+        function addOldTypeMetadata(node, container, decoratorExpressions) {
+            if (compilerOptions.emitDecoratorMetadata) {
+                if (shouldAddTypeMetadata(node)) {
+                    decoratorExpressions.push(createMetadataHelper(context, "design:type", serializeTypeOfNode(node)));
+                }
+                if (shouldAddParamTypesMetadata(node)) {
+                    decoratorExpressions.push(createMetadataHelper(context, "design:paramtypes", serializeParameterTypesOfNode(node, container)));
+                }
+                if (shouldAddReturnTypeMetadata(node)) {
+                    decoratorExpressions.push(createMetadataHelper(context, "design:returntype", serializeReturnTypeOfNode(node)));
+                }
+            }
+        }
+        function addNewTypeMetadata(node, container, decoratorExpressions) {
+            if (compilerOptions.emitDecoratorMetadata) {
+                var properties = void 0;
+                if (shouldAddTypeMetadata(node)) {
+                    (properties || (properties = [])).push(ts.createPropertyAssignment("type", ts.createArrowFunction(/*modifiers*/ undefined, /*typeParameters*/ undefined, [], /*type*/ undefined, ts.createToken(36 /* EqualsGreaterThanToken */), serializeTypeOfNode(node))));
+                }
+                if (shouldAddParamTypesMetadata(node)) {
+                    (properties || (properties = [])).push(ts.createPropertyAssignment("paramTypes", ts.createArrowFunction(/*modifiers*/ undefined, /*typeParameters*/ undefined, [], /*type*/ undefined, ts.createToken(36 /* EqualsGreaterThanToken */), serializeParameterTypesOfNode(node, container))));
+                }
+                if (shouldAddReturnTypeMetadata(node)) {
+                    (properties || (properties = [])).push(ts.createPropertyAssignment("returnType", ts.createArrowFunction(/*modifiers*/ undefined, /*typeParameters*/ undefined, [], /*type*/ undefined, ts.createToken(36 /* EqualsGreaterThanToken */), serializeReturnTypeOfNode(node))));
+                }
+                if (properties) {
+                    decoratorExpressions.push(createMetadataHelper(context, "design:typeinfo", ts.createObjectLiteral(properties, /*multiLine*/ true)));
+                }
+            }
+        }
+        /**
+         * Determines whether to emit the "design:type" metadata based on the node's kind.
+         * The caller should have already tested whether the node has decorators and whether the
+         * emitDecoratorMetadata compiler option is set.
+         *
+         * @param node The node to test.
+         */
+        function shouldAddTypeMetadata(node) {
+            var kind = node.kind;
+            return kind === 154 /* MethodDeclaration */
+                || kind === 156 /* GetAccessor */
+                || kind === 157 /* SetAccessor */
+                || kind === 152 /* PropertyDeclaration */;
+        }
+        /**
+         * Determines whether to emit the "design:returntype" metadata based on the node's kind.
+         * The caller should have already tested whether the node has decorators and whether the
+         * emitDecoratorMetadata compiler option is set.
+         *
+         * @param node The node to test.
+         */
+        function shouldAddReturnTypeMetadata(node) {
+            return node.kind === 154 /* MethodDeclaration */;
+        }
+        /**
+         * Determines whether to emit the "design:paramtypes" metadata based on the node's kind.
+         * The caller should have already tested whether the node has decorators and whether the
+         * emitDecoratorMetadata compiler option is set.
+         *
+         * @param node The node to test.
+         */
+        function shouldAddParamTypesMetadata(node) {
+            switch (node.kind) {
+                case 235 /* ClassDeclaration */:
+                case 205 /* ClassExpression */:
+                    return ts.getFirstConstructorWithBody(node) !== undefined;
+                case 154 /* MethodDeclaration */:
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                    return true;
+            }
+            return false;
+        }
+        /**
+         * Serializes the type of a node for use with decorator type metadata.
+         *
+         * @param node The node that should have its type serialized.
+         */
+        function serializeTypeOfNode(node) {
+            switch (node.kind) {
+                case 152 /* PropertyDeclaration */:
+                case 149 /* Parameter */:
+                case 156 /* GetAccessor */:
+                    return serializeTypeNode(node.type);
+                case 157 /* SetAccessor */:
+                    return serializeTypeNode(ts.getSetAccessorTypeAnnotationNode(node));
+                case 235 /* ClassDeclaration */:
+                case 205 /* ClassExpression */:
+                case 154 /* MethodDeclaration */:
+                    return ts.createIdentifier("Function");
+                default:
+                    return ts.createVoidZero();
+            }
+        }
+        /**
+         * Serializes the types of the parameters of a node for use with decorator type metadata.
+         *
+         * @param node The node that should have its parameter types serialized.
+         */
+        function serializeParameterTypesOfNode(node, container) {
+            var valueDeclaration = ts.isClassLike(node)
+                ? ts.getFirstConstructorWithBody(node)
+                : ts.isFunctionLike(node) && ts.nodeIsPresent(node.body)
+                    ? node
+                    : undefined;
+            var expressions = [];
+            if (valueDeclaration) {
+                var parameters = getParametersOfDecoratedDeclaration(valueDeclaration, container);
+                var numParameters = parameters.length;
+                for (var i = 0; i < numParameters; i++) {
+                    var parameter = parameters[i];
+                    if (i === 0 && ts.isIdentifier(parameter.name) && parameter.name.escapedText === "this") {
+                        continue;
+                    }
+                    if (parameter.dotDotDotToken) {
+                        expressions.push(serializeTypeNode(ts.getRestParameterElementType(parameter.type)));
+                    }
+                    else {
+                        expressions.push(serializeTypeOfNode(parameter));
+                    }
+                }
+            }
+            return ts.createArrayLiteral(expressions);
+        }
+        function getParametersOfDecoratedDeclaration(node, container) {
+            if (container && node.kind === 156 /* GetAccessor */) {
+                var setAccessor = ts.getAllAccessorDeclarations(container.members, node).setAccessor;
+                if (setAccessor) {
+                    return setAccessor.parameters;
+                }
+            }
+            return node.parameters;
+        }
+        /**
+         * Serializes the return type of a node for use with decorator type metadata.
+         *
+         * @param node The node that should have its return type serialized.
+         */
+        function serializeReturnTypeOfNode(node) {
+            if (ts.isFunctionLike(node) && node.type) {
+                return serializeTypeNode(node.type);
+            }
+            else if (ts.isAsyncFunction(node)) {
+                return ts.createIdentifier("Promise");
+            }
+            return ts.createVoidZero();
+        }
+        /**
+         * Serializes a type node for use with decorator type metadata.
+         *
+         * Types are serialized in the following fashion:
+         * - Void types point to "undefined" (e.g. "void 0")
+         * - Function and Constructor types point to the global "Function" constructor.
+         * - Interface types with a call or construct signature types point to the global
+         *   "Function" constructor.
+         * - Array and Tuple types point to the global "Array" constructor.
+         * - Type predicates and booleans point to the global "Boolean" constructor.
+         * - String literal types and strings point to the global "String" constructor.
+         * - Enum and number types point to the global "Number" constructor.
+         * - Symbol types point to the global "Symbol" constructor.
+         * - Type references to classes (or class-like variables) point to the constructor for the class.
+         * - Anything else points to the global "Object" constructor.
+         *
+         * @param node The type node to serialize.
+         */
+        function serializeTypeNode(node) {
+            if (node === undefined) {
+                return ts.createIdentifier("Object");
+            }
+            switch (node.kind) {
+                case 105 /* VoidKeyword */:
+                case 140 /* UndefinedKeyword */:
+                case 95 /* NullKeyword */:
+                case 131 /* NeverKeyword */:
+                    return ts.createVoidZero();
+                case 173 /* ParenthesizedType */:
+                    return serializeTypeNode(node.type);
+                case 163 /* FunctionType */:
+                case 164 /* ConstructorType */:
+                    return ts.createIdentifier("Function");
+                case 167 /* ArrayType */:
+                case 168 /* TupleType */:
+                    return ts.createIdentifier("Array");
+                case 161 /* TypePredicate */:
+                case 122 /* BooleanKeyword */:
+                    return ts.createIdentifier("Boolean");
+                case 137 /* StringKeyword */:
+                    return ts.createIdentifier("String");
+                case 135 /* ObjectKeyword */:
+                    return ts.createIdentifier("Object");
+                case 178 /* LiteralType */:
+                    switch (node.literal.kind) {
+                        case 9 /* StringLiteral */:
+                            return ts.createIdentifier("String");
+                        case 8 /* NumericLiteral */:
+                            return ts.createIdentifier("Number");
+                        case 101 /* TrueKeyword */:
+                        case 86 /* FalseKeyword */:
+                            return ts.createIdentifier("Boolean");
+                        default:
+                            return ts.Debug.failBadSyntaxKind(node.literal);
+                    }
+                case 134 /* NumberKeyword */:
+                    return ts.createIdentifier("Number");
+                case 138 /* SymbolKeyword */:
+                    return languageVersion < 2 /* ES2015 */
+                        ? getGlobalSymbolNameWithFallback()
+                        : ts.createIdentifier("Symbol");
+                case 162 /* TypeReference */:
+                    return serializeTypeReferenceNode(node);
+                case 170 /* IntersectionType */:
+                case 169 /* UnionType */:
+                    return serializeUnionOrIntersectionType(node);
+                case 165 /* TypeQuery */:
+                case 175 /* TypeOperator */:
+                case 176 /* IndexedAccessType */:
+                case 177 /* MappedType */:
+                case 166 /* TypeLiteral */:
+                case 119 /* AnyKeyword */:
+                case 142 /* UnknownKeyword */:
+                case 174 /* ThisType */:
+                case 179 /* ImportType */:
+                    break;
+                default:
+                    return ts.Debug.failBadSyntaxKind(node);
+            }
+            return ts.createIdentifier("Object");
+        }
+        function serializeUnionOrIntersectionType(node) {
+            // Note when updating logic here also update getEntityNameForDecoratorMetadata
+            // so that aliases can be marked as referenced
+            var serializedUnion;
+            for (var _i = 0, _a = node.types; _i < _a.length; _i++) {
+                var typeNode = _a[_i];
+                while (typeNode.kind === 173 /* ParenthesizedType */) {
+                    typeNode = typeNode.type; // Skip parens if need be
+                }
+                if (typeNode.kind === 131 /* NeverKeyword */) {
+                    continue; // Always elide `never` from the union/intersection if possible
+                }
+                if (!strictNullChecks && (typeNode.kind === 95 /* NullKeyword */ || typeNode.kind === 140 /* UndefinedKeyword */)) {
+                    continue; // Elide null and undefined from unions for metadata, just like what we did prior to the implementation of strict null checks
+                }
+                var serializedIndividual = serializeTypeNode(typeNode);
+                if (ts.isIdentifier(serializedIndividual) && serializedIndividual.escapedText === "Object") {
+                    // One of the individual is global object, return immediately
+                    return serializedIndividual;
+                }
+                // If there exists union that is not void 0 expression, check if the the common type is identifier.
+                // anything more complex and we will just default to Object
+                else if (serializedUnion) {
+                    // Different types
+                    if (!ts.isIdentifier(serializedUnion) ||
+                        !ts.isIdentifier(serializedIndividual) ||
+                        serializedUnion.escapedText !== serializedIndividual.escapedText) {
+                        return ts.createIdentifier("Object");
+                    }
+                }
+                else {
+                    // Initialize the union type
+                    serializedUnion = serializedIndividual;
+                }
+            }
+            // If we were able to find common type, use it
+            return serializedUnion || ts.createVoidZero(); // Fallback is only hit if all union constituients are null/undefined/never
+        }
+        /**
+         * Serializes a TypeReferenceNode to an appropriate JS constructor value for use with
+         * decorator type metadata.
+         *
+         * @param node The type reference node.
+         */
+        function serializeTypeReferenceNode(node) {
+            var kind = resolver.getTypeReferenceSerializationKind(node.typeName, currentScope);
+            switch (kind) {
+                case ts.TypeReferenceSerializationKind.Unknown:
+                    var serialized = serializeEntityNameAsExpression(node.typeName, /*useFallback*/ true);
+                    var temp = ts.createTempVariable(hoistVariableDeclaration);
+                    return ts.createLogicalOr(ts.createLogicalAnd(ts.createTypeCheck(ts.createAssignment(temp, serialized), "function"), temp), ts.createIdentifier("Object"));
+                case ts.TypeReferenceSerializationKind.TypeWithConstructSignatureAndValue:
+                    return serializeEntityNameAsExpression(node.typeName, /*useFallback*/ false);
+                case ts.TypeReferenceSerializationKind.VoidNullableOrNeverType:
+                    return ts.createVoidZero();
+                case ts.TypeReferenceSerializationKind.BooleanType:
+                    return ts.createIdentifier("Boolean");
+                case ts.TypeReferenceSerializationKind.NumberLikeType:
+                    return ts.createIdentifier("Number");
+                case ts.TypeReferenceSerializationKind.StringLikeType:
+                    return ts.createIdentifier("String");
+                case ts.TypeReferenceSerializationKind.ArrayLikeType:
+                    return ts.createIdentifier("Array");
+                case ts.TypeReferenceSerializationKind.ESSymbolType:
+                    return languageVersion < 2 /* ES2015 */
+                        ? getGlobalSymbolNameWithFallback()
+                        : ts.createIdentifier("Symbol");
+                case ts.TypeReferenceSerializationKind.TypeWithCallSignature:
+                    return ts.createIdentifier("Function");
+                case ts.TypeReferenceSerializationKind.Promise:
+                    return ts.createIdentifier("Promise");
+                case ts.TypeReferenceSerializationKind.ObjectType:
+                    return ts.createIdentifier("Object");
+                default:
+                    return ts.Debug.assertNever(kind);
+            }
+        }
+        /**
+         * Serializes an entity name as an expression for decorator type metadata.
+         *
+         * @param node The entity name to serialize.
+         * @param useFallback A value indicating whether to use logical operators to test for the
+         *                    entity name at runtime.
+         */
+        function serializeEntityNameAsExpression(node, useFallback) {
+            switch (node.kind) {
+                case 71 /* Identifier */:
+                    // Create a clone of the name with a new parent, and treat it as if it were
+                    // a source tree node for the purposes of the checker.
+                    var name = ts.getMutableClone(node);
+                    name.flags &= ~8 /* Synthesized */;
+                    name.original = undefined;
+                    name.parent = ts.getParseTreeNode(currentScope); // ensure the parent is set to a parse tree node.
+                    if (useFallback) {
+                        return ts.createLogicalAnd(ts.createStrictInequality(ts.createTypeOf(name), ts.createLiteral("undefined")), name);
+                    }
+                    return name;
+                case 146 /* QualifiedName */:
+                    return serializeQualifiedNameAsExpression(node, useFallback);
+            }
+        }
+        /**
+         * Serializes an qualified name as an expression for decorator type metadata.
+         *
+         * @param node The qualified name to serialize.
+         * @param useFallback A value indicating whether to use logical operators to test for the
+         *                    qualified name at runtime.
+         */
+        function serializeQualifiedNameAsExpression(node, useFallback) {
+            var left;
+            if (node.left.kind === 71 /* Identifier */) {
+                left = serializeEntityNameAsExpression(node.left, useFallback);
+            }
+            else if (useFallback) {
+                var temp = ts.createTempVariable(hoistVariableDeclaration);
+                left = ts.createLogicalAnd(ts.createAssignment(temp, serializeEntityNameAsExpression(node.left, /*useFallback*/ true)), temp);
+            }
+            else {
+                left = serializeEntityNameAsExpression(node.left, /*useFallback*/ false);
+            }
+            return ts.createPropertyAccess(left, node.right);
+        }
+        /**
+         * Gets an expression that points to the global "Symbol" constructor at runtime if it is
+         * available.
+         */
+        function getGlobalSymbolNameWithFallback() {
+            return ts.createConditional(ts.createTypeCheck(ts.createIdentifier("Symbol"), "function"), ts.createIdentifier("Symbol"), ts.createIdentifier("Object"));
+        }
+        /**
+         * A simple inlinable expression is an expression which can be copied into multiple locations
+         * without risk of repeating any sideeffects and whose value could not possibly change between
+         * any such locations
+         */
+        function isSimpleInlineableExpression(expression) {
+            return !ts.isIdentifier(expression) && ts.isSimpleCopiableExpression(expression) ||
+                ts.isWellKnownSymbolSyntactically(expression);
+        }
+        /**
+         * Gets an expression that represents a property name. For a computed property, a
+         * name is generated for the node.
+         *
+         * @param member The member whose name should be converted into an expression.
+         */
+        function getExpressionForPropertyName(member, generateNameForComputedPropertyName) {
+            var name = member.name;
+            if (ts.isComputedPropertyName(name)) {
+                return generateNameForComputedPropertyName && !isSimpleInlineableExpression(name.expression)
+                    ? ts.getGeneratedNameForNode(name)
+                    : name.expression;
+            }
+            else if (ts.isIdentifier(name)) {
+                return ts.createLiteral(ts.idText(name));
+            }
+            else {
+                return ts.getSynthesizedClone(name);
+            }
+        }
+        /**
+         * If the name is a computed property, this function transforms it, then either returns an expression which caches the
+         * value of the result or the expression itself if the value is either unused or safe to inline into multiple locations
+         * @param shouldHoist Does the expression need to be reused? (ie, for an initializer or a decorator)
+         * @param omitSimple Should expressions with no observable side-effects be elided? (ie, the expression is not hoisted for a decorator or initializer and is a literal)
+         */
+        function getPropertyNameExpressionIfNeeded(name, shouldHoist, omitSimple) {
+            if (ts.isComputedPropertyName(name)) {
+                var expression = ts.visitNode(name.expression, visitor, ts.isExpression);
+                var innerExpression = ts.skipPartiallyEmittedExpressions(expression);
+                var inlinable = isSimpleInlineableExpression(innerExpression);
+                if (!inlinable && shouldHoist) {
+                    var generatedName = ts.getGeneratedNameForNode(name);
+                    hoistVariableDeclaration(generatedName);
+                    return ts.createAssignment(generatedName, expression);
+                }
+                return (omitSimple && (inlinable || ts.isIdentifier(innerExpression))) ? undefined : expression;
+            }
+        }
+        /**
+         * Visits the property name of a class element, for use when emitting property
+         * initializers. For a computed property on a node with decorators, a temporary
+         * value is stored for later use.
+         *
+         * @param member The member whose name should be visited.
+         */
+        function visitPropertyNameOfClassElement(member) {
+            var name = member.name;
+            var expr = getPropertyNameExpressionIfNeeded(name, ts.some(member.decorators), /*omitSimple*/ false);
+            if (expr) { // expr only exists if `name` is a computed property name
+                // Inline any pending expressions from previous elided or relocated computed property name expressions in order to preserve execution order
+                if (ts.some(pendingExpressions)) {
+                    expr = ts.inlineExpressions(pendingExpressions.concat([expr]));
+                    pendingExpressions.length = 0;
+                }
+                return ts.updateComputedPropertyName(name, expr);
+            }
+            else {
+                return name;
+            }
+        }
+        /**
+         * Transforms a HeritageClause with TypeScript syntax.
+         *
+         * This function will only be called when one of the following conditions are met:
+         * - The node is a non-`extends` heritage clause that should be elided.
+         * - The node is an `extends` heritage clause that should be visited, but only allow a single type.
+         *
+         * @param node The HeritageClause to transform.
+         */
+        function visitHeritageClause(node) {
+            if (node.token === 85 /* ExtendsKeyword */) {
+                var types = ts.visitNodes(node.types, visitor, ts.isExpressionWithTypeArguments, 0, 1);
+                return ts.setTextRange(ts.createHeritageClause(85 /* ExtendsKeyword */, types), node);
+            }
+            return undefined;
+        }
+        /**
+         * Transforms an ExpressionWithTypeArguments with TypeScript syntax.
+         *
+         * This function will only be called when one of the following conditions are met:
+         * - The node contains type arguments that should be elided.
+         *
+         * @param node The ExpressionWithTypeArguments to transform.
+         */
+        function visitExpressionWithTypeArguments(node) {
+            return ts.updateExpressionWithTypeArguments(node, 
+            /*typeArguments*/ undefined, ts.visitNode(node.expression, visitor, ts.isLeftHandSideExpression));
+        }
+        /**
+         * Determines whether to emit a function-like declaration. We should not emit the
+         * declaration if it does not have a body.
+         *
+         * @param node The declaration node.
+         */
+        function shouldEmitFunctionLikeDeclaration(node) {
+            return !ts.nodeIsMissing(node.body);
+        }
+        function visitPropertyDeclaration(node) {
+            var expr = getPropertyNameExpressionIfNeeded(node.name, ts.some(node.decorators) || !!node.initializer, /*omitSimple*/ true);
+            if (expr && !isSimpleInlineableExpression(expr)) {
+                (pendingExpressions || (pendingExpressions = [])).push(expr);
+            }
+            return undefined;
+        }
+        function visitConstructor(node) {
+            if (!shouldEmitFunctionLikeDeclaration(node)) {
+                return undefined;
+            }
+            return ts.updateConstructor(node, ts.visitNodes(node.decorators, visitor, ts.isDecorator), ts.visitNodes(node.modifiers, visitor, ts.isModifier), ts.visitParameterList(node.parameters, visitor, context), ts.visitFunctionBody(node.body, visitor, context));
+        }
+        /**
+         * Visits a method declaration of a class.
+         *
+         * This function will be called when one of the following conditions are met:
+         * - The node is an overload
+         * - The node is marked as abstract, public, private, protected, or readonly
+         * - The node has a computed property name
+         *
+         * @param node The method node.
+         */
+        function visitMethodDeclaration(node) {
+            if (!shouldEmitFunctionLikeDeclaration(node)) {
+                return undefined;
+            }
+            var updated = ts.updateMethod(node, 
+            /*decorators*/ undefined, ts.visitNodes(node.modifiers, modifierVisitor, ts.isModifier), node.asteriskToken, visitPropertyNameOfClassElement(node), 
+            /*questionToken*/ undefined, 
+            /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, ts.visitFunctionBody(node.body, visitor, context));
+            if (updated !== node) {
+                // While we emit the source map for the node after skipping decorators and modifiers,
+                // we need to emit the comments for the original range.
+                ts.setCommentRange(updated, node);
+                ts.setSourceMapRange(updated, ts.moveRangePastDecorators(node));
+            }
+            return updated;
+        }
+        /**
+         * Determines whether to emit an accessor declaration. We should not emit the
+         * declaration if it does not have a body and is abstract.
+         *
+         * @param node The declaration node.
+         */
+        function shouldEmitAccessorDeclaration(node) {
+            return !(ts.nodeIsMissing(node.body) && ts.hasModifier(node, 128 /* Abstract */));
+        }
+        /**
+         * Visits a get accessor declaration of a class.
+         *
+         * This function will be called when one of the following conditions are met:
+         * - The node is marked as abstract, public, private, or protected
+         * - The node has a computed property name
+         *
+         * @param node The get accessor node.
+         */
+        function visitGetAccessor(node) {
+            if (!shouldEmitAccessorDeclaration(node)) {
+                return undefined;
+            }
+            var updated = ts.updateGetAccessor(node, 
+            /*decorators*/ undefined, ts.visitNodes(node.modifiers, modifierVisitor, ts.isModifier), visitPropertyNameOfClassElement(node), ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, ts.visitFunctionBody(node.body, visitor, context) || ts.createBlock([]));
+            if (updated !== node) {
+                // While we emit the source map for the node after skipping decorators and modifiers,
+                // we need to emit the comments for the original range.
+                ts.setCommentRange(updated, node);
+                ts.setSourceMapRange(updated, ts.moveRangePastDecorators(node));
+            }
+            return updated;
+        }
+        /**
+         * Visits a set accessor declaration of a class.
+         *
+         * This function will be called when one of the following conditions are met:
+         * - The node is marked as abstract, public, private, or protected
+         * - The node has a computed property name
+         *
+         * @param node The set accessor node.
+         */
+        function visitSetAccessor(node) {
+            if (!shouldEmitAccessorDeclaration(node)) {
+                return undefined;
+            }
+            var updated = ts.updateSetAccessor(node, 
+            /*decorators*/ undefined, ts.visitNodes(node.modifiers, modifierVisitor, ts.isModifier), visitPropertyNameOfClassElement(node), ts.visitParameterList(node.parameters, visitor, context), ts.visitFunctionBody(node.body, visitor, context) || ts.createBlock([]));
+            if (updated !== node) {
+                // While we emit the source map for the node after skipping decorators and modifiers,
+                // we need to emit the comments for the original range.
+                ts.setCommentRange(updated, node);
+                ts.setSourceMapRange(updated, ts.moveRangePastDecorators(node));
+            }
+            return updated;
+        }
+        /**
+         * Visits a function declaration.
+         *
+         * This function will be called when one of the following conditions are met:
+         * - The node is an overload
+         * - The node is exported from a TypeScript namespace
+         * - The node has decorators
+         *
+         * @param node The function node.
+         */
+        function visitFunctionDeclaration(node) {
+            if (!shouldEmitFunctionLikeDeclaration(node)) {
+                return ts.createNotEmittedStatement(node);
+            }
+            var updated = ts.updateFunctionDeclaration(node, 
+            /*decorators*/ undefined, ts.visitNodes(node.modifiers, modifierVisitor, ts.isModifier), node.asteriskToken, node.name, 
+            /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, ts.visitFunctionBody(node.body, visitor, context) || ts.createBlock([]));
+            if (isExportOfNamespace(node)) {
+                var statements = [updated];
+                addExportMemberAssignment(statements, node);
+                return statements;
+            }
+            return updated;
+        }
+        /**
+         * Visits a function expression node.
+         *
+         * This function will be called when one of the following conditions are met:
+         * - The node has type annotations
+         *
+         * @param node The function expression node.
+         */
+        function visitFunctionExpression(node) {
+            if (!shouldEmitFunctionLikeDeclaration(node)) {
+                return ts.createOmittedExpression();
+            }
+            var updated = ts.updateFunctionExpression(node, ts.visitNodes(node.modifiers, modifierVisitor, ts.isModifier), node.asteriskToken, node.name, 
+            /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, ts.visitFunctionBody(node.body, visitor, context) || ts.createBlock([]));
+            return updated;
+        }
+        /**
+         * @remarks
+         * This function will be called when one of the following conditions are met:
+         * - The node has type annotations
+         */
+        function visitArrowFunction(node) {
+            var updated = ts.updateArrowFunction(node, ts.visitNodes(node.modifiers, modifierVisitor, ts.isModifier), 
+            /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, node.equalsGreaterThanToken, ts.visitFunctionBody(node.body, visitor, context));
+            return updated;
+        }
+        /**
+         * Visits a parameter declaration node.
+         *
+         * This function will be called when one of the following conditions are met:
+         * - The node has an accessibility modifier.
+         * - The node has a questionToken.
+         * - The node's kind is ThisKeyword.
+         *
+         * @param node The parameter declaration node.
+         */
+        function visitParameter(node) {
+            if (ts.parameterIsThisKeyword(node)) {
+                return undefined;
+            }
+            var parameter = ts.createParameter(
+            /*decorators*/ undefined, 
+            /*modifiers*/ undefined, node.dotDotDotToken, ts.visitNode(node.name, visitor, ts.isBindingName), 
+            /*questionToken*/ undefined, 
+            /*type*/ undefined, ts.visitNode(node.initializer, visitor, ts.isExpression));
+            // While we emit the source map for the node after skipping decorators and modifiers,
+            // we need to emit the comments for the original range.
+            ts.setOriginalNode(parameter, node);
+            ts.setTextRange(parameter, ts.moveRangePastModifiers(node));
+            ts.setCommentRange(parameter, node);
+            ts.setSourceMapRange(parameter, ts.moveRangePastModifiers(node));
+            ts.setEmitFlags(parameter.name, 32 /* NoTrailingSourceMap */);
+            return parameter;
+        }
+        /**
+         * Visits a variable statement in a namespace.
+         *
+         * This function will be called when one of the following conditions are met:
+         * - The node is exported from a TypeScript namespace.
+         */
+        function visitVariableStatement(node) {
+            if (isExportOfNamespace(node)) {
+                var variables = ts.getInitializedVariables(node.declarationList);
+                if (variables.length === 0) {
+                    // elide statement if there are no initialized variables.
+                    return undefined;
+                }
+                return ts.setTextRange(ts.createStatement(ts.inlineExpressions(ts.map(variables, transformInitializedVariable))), node);
+            }
+            else {
+                return ts.visitEachChild(node, visitor, context);
+            }
+        }
+        function transformInitializedVariable(node) {
+            var name = node.name;
+            if (ts.isBindingPattern(name)) {
+                return ts.flattenDestructuringAssignment(node, visitor, context, 0 /* All */, 
+                /*needsValue*/ false, createNamespaceExportExpression);
+            }
+            else {
+                return ts.setTextRange(ts.createAssignment(getNamespaceMemberNameWithSourceMapsAndWithoutComments(name), ts.visitNode(node.initializer, visitor, ts.isExpression)), 
+                /*location*/ node);
+            }
+        }
+        function visitVariableDeclaration(node) {
+            return ts.updateVariableDeclaration(node, ts.visitNode(node.name, visitor, ts.isBindingName), 
+            /*type*/ undefined, ts.visitNode(node.initializer, visitor, ts.isExpression));
+        }
+        /**
+         * Visits a parenthesized expression that contains either a type assertion or an `as`
+         * expression.
+         *
+         * @param node The parenthesized expression node.
+         */
+        function visitParenthesizedExpression(node) {
+            var innerExpression = ts.skipOuterExpressions(node.expression, ~2 /* Assertions */);
+            if (ts.isAssertionExpression(innerExpression)) {
+                // Make sure we consider all nested cast expressions, e.g.:
+                // (<any><number><any>-A).x;
+                var expression = ts.visitNode(node.expression, visitor, ts.isExpression);
+                // We have an expression of the form: (<Type>SubExpr). Emitting this as (SubExpr)
+                // is really not desirable. We would like to emit the subexpression as-is. Omitting
+                // the parentheses, however, could cause change in the semantics of the generated
+                // code if the casted expression has a lower precedence than the rest of the
+                // expression.
+                //
+                // To preserve comments, we return a "PartiallyEmittedExpression" here which will
+                // preserve the position information of the original expression.
+                //
+                // Due to the auto-parenthesization rules used by the visitor and factory functions
+                // we can safely elide the parentheses here, as a new synthetic
+                // ParenthesizedExpression will be inserted if we remove parentheses too
+                // aggressively.
+                // HOWEVER - if there are leading comments on the expression itself, to handle ASI
+                // correctly for return and throw, we must keep the parenthesis
+                if (ts.length(ts.getLeadingCommentRangesOfNode(expression, currentSourceFile))) {
+                    return ts.updateParen(node, expression);
+                }
+                return ts.createPartiallyEmittedExpression(expression, node);
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitAssertionExpression(node) {
+            var expression = ts.visitNode(node.expression, visitor, ts.isExpression);
+            return ts.createPartiallyEmittedExpression(expression, node);
+        }
+        function visitNonNullExpression(node) {
+            var expression = ts.visitNode(node.expression, visitor, ts.isLeftHandSideExpression);
+            return ts.createPartiallyEmittedExpression(expression, node);
+        }
+        function visitCallExpression(node) {
+            return ts.updateCall(node, ts.visitNode(node.expression, visitor, ts.isExpression), 
+            /*typeArguments*/ undefined, ts.visitNodes(node.arguments, visitor, ts.isExpression));
+        }
+        function visitNewExpression(node) {
+            return ts.updateNew(node, ts.visitNode(node.expression, visitor, ts.isExpression), 
+            /*typeArguments*/ undefined, ts.visitNodes(node.arguments, visitor, ts.isExpression));
+        }
+        function visitTaggedTemplateExpression(node) {
+            return ts.updateTaggedTemplate(node, ts.visitNode(node.tag, visitor, ts.isExpression), 
+            /*typeArguments*/ undefined, ts.visitNode(node.template, visitor, ts.isExpression));
+        }
+        /**
+         * Determines whether to emit an enum declaration.
+         *
+         * @param node The enum declaration node.
+         */
+        function shouldEmitEnumDeclaration(node) {
+            return !ts.isConst(node)
+                || compilerOptions.preserveConstEnums
+                || compilerOptions.isolatedModules;
+        }
+        /**
+         * Visits an enum declaration.
+         *
+         * This function will be called any time a TypeScript enum is encountered.
+         *
+         * @param node The enum declaration node.
+         */
+        function visitEnumDeclaration(node) {
+            if (!shouldEmitEnumDeclaration(node)) {
+                return undefined;
+            }
+            var statements = [];
+            // We request to be advised when the printer is about to print this node. This allows
+            // us to set up the correct state for later substitutions.
+            var emitFlags = 2 /* AdviseOnEmitNode */;
+            // If needed, we should emit a variable declaration for the enum. If we emit
+            // a leading variable declaration, we should not emit leading comments for the
+            // enum body.
+            if (addVarForEnumOrModuleDeclaration(statements, node)) {
+                // We should still emit the comments if we are emitting a system module.
+                if (moduleKind !== ts.ModuleKind.System || currentScope !== currentSourceFile) {
+                    emitFlags |= 512 /* NoLeadingComments */;
+                }
+            }
+            // `parameterName` is the declaration name used inside of the enum.
+            var parameterName = getNamespaceParameterName(node);
+            // `containerName` is the expression used inside of the enum for assignments.
+            var containerName = getNamespaceContainerName(node);
+            // `exportName` is the expression used within this node's container for any exported references.
+            var exportName = ts.hasModifier(node, 1 /* Export */)
+                ? ts.getExternalModuleOrNamespaceExportName(currentNamespaceContainerName, node, /*allowComments*/ false, /*allowSourceMaps*/ true)
+                : ts.getLocalName(node, /*allowComments*/ false, /*allowSourceMaps*/ true);
+            //  x || (x = {})
+            //  exports.x || (exports.x = {})
+            var moduleArg = ts.createLogicalOr(exportName, ts.createAssignment(exportName, ts.createObjectLiteral()));
+            if (hasNamespaceQualifiedExportName(node)) {
+                // `localName` is the expression used within this node's containing scope for any local references.
+                var localName = ts.getLocalName(node, /*allowComments*/ false, /*allowSourceMaps*/ true);
+                //  x = (exports.x || (exports.x = {}))
+                moduleArg = ts.createAssignment(localName, moduleArg);
+            }
+            //  (function (x) {
+            //      x[x["y"] = 0] = "y";
+            //      ...
+            //  })(x || (x = {}));
+            var enumStatement = ts.createStatement(ts.createCall(ts.createFunctionExpression(
+            /*modifiers*/ undefined, 
+            /*asteriskToken*/ undefined, 
+            /*name*/ undefined, 
+            /*typeParameters*/ undefined, [ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, parameterName)], 
+            /*type*/ undefined, transformEnumBody(node, containerName)), 
+            /*typeArguments*/ undefined, [moduleArg]));
+            ts.setOriginalNode(enumStatement, node);
+            ts.setTextRange(enumStatement, node);
+            ts.setEmitFlags(enumStatement, emitFlags);
+            statements.push(enumStatement);
+            // Add a DeclarationMarker for the enum to preserve trailing comments and mark
+            // the end of the declaration.
+            statements.push(ts.createEndOfDeclarationMarker(node));
+            return statements;
+        }
+        /**
+         * Transforms the body of an enum declaration.
+         *
+         * @param node The enum declaration node.
+         */
+        function transformEnumBody(node, localName) {
+            var savedCurrentNamespaceLocalName = currentNamespaceContainerName;
+            currentNamespaceContainerName = localName;
+            var statements = [];
+            startLexicalEnvironment();
+            var members = ts.map(node.members, transformEnumMember);
+            ts.prependStatements(statements, endLexicalEnvironment());
+            ts.addRange(statements, members);
+            currentNamespaceContainerName = savedCurrentNamespaceLocalName;
+            return ts.createBlock(ts.setTextRange(ts.createNodeArray(statements), /*location*/ node.members), 
+            /*multiLine*/ true);
+        }
+        /**
+         * Transforms an enum member into a statement.
+         *
+         * @param member The enum member node.
+         */
+        function transformEnumMember(member) {
+            // enums don't support computed properties
+            // we pass false as 'generateNameForComputedPropertyName' for a backward compatibility purposes
+            // old emitter always generate 'expression' part of the name as-is.
+            var name = getExpressionForPropertyName(member, /*generateNameForComputedPropertyName*/ false);
+            var valueExpression = transformEnumMemberDeclarationValue(member);
+            var innerAssignment = ts.createAssignment(ts.createElementAccess(currentNamespaceContainerName, name), valueExpression);
+            var outerAssignment = valueExpression.kind === 9 /* StringLiteral */ ?
+                innerAssignment :
+                ts.createAssignment(ts.createElementAccess(currentNamespaceContainerName, innerAssignment), name);
+            return ts.setTextRange(ts.createStatement(ts.setTextRange(outerAssignment, member)), member);
+        }
+        /**
+         * Transforms the value of an enum member.
+         *
+         * @param member The enum member node.
+         */
+        function transformEnumMemberDeclarationValue(member) {
+            var value = resolver.getConstantValue(member);
+            if (value !== undefined) {
+                return ts.createLiteral(value);
+            }
+            else {
+                enableSubstitutionForNonQualifiedEnumMembers();
+                if (member.initializer) {
+                    return ts.visitNode(member.initializer, visitor, ts.isExpression);
+                }
+                else {
+                    return ts.createVoidZero();
+                }
+            }
+        }
+        /**
+         * Determines whether to elide a module declaration.
+         *
+         * @param node The module declaration node.
+         */
+        function shouldEmitModuleDeclaration(node) {
+            return ts.isInstantiatedModule(node, !!compilerOptions.preserveConstEnums || !!compilerOptions.isolatedModules);
+        }
+        /**
+         * Determines whether an exported declaration will have a qualified export name (e.g. `f.x`
+         * or `exports.x`).
+         */
+        function hasNamespaceQualifiedExportName(node) {
+            return isExportOfNamespace(node)
+                || (isExternalModuleExport(node)
+                    && moduleKind !== ts.ModuleKind.ES2015
+                    && moduleKind !== ts.ModuleKind.ESNext
+                    && moduleKind !== ts.ModuleKind.System);
+        }
+        /**
+         * Records that a declaration was emitted in the current scope, if it was the first
+         * declaration for the provided symbol.
+         */
+        function recordEmittedDeclarationInScope(node) {
+            if (!currentScopeFirstDeclarationsOfName) {
+                currentScopeFirstDeclarationsOfName = ts.createUnderscoreEscapedMap();
+            }
+            var name = declaredNameInScope(node);
+            if (!currentScopeFirstDeclarationsOfName.has(name)) {
+                currentScopeFirstDeclarationsOfName.set(name, node);
+            }
+        }
+        /**
+         * Determines whether a declaration is the first declaration with
+         * the same name emitted in the current scope.
+         */
+        function isFirstEmittedDeclarationInScope(node) {
+            if (currentScopeFirstDeclarationsOfName) {
+                var name = declaredNameInScope(node);
+                return currentScopeFirstDeclarationsOfName.get(name) === node;
+            }
+            return true;
+        }
+        function declaredNameInScope(node) {
+            ts.Debug.assertNode(node.name, ts.isIdentifier);
+            return node.name.escapedText;
+        }
+        /**
+         * Adds a leading VariableStatement for a enum or module declaration.
+         */
+        function addVarForEnumOrModuleDeclaration(statements, node) {
+            // Emit a variable statement for the module. We emit top-level enums as a `var`
+            // declaration to avoid static errors in global scripts scripts due to redeclaration.
+            // enums in any other scope are emitted as a `let` declaration.
+            var statement = ts.createVariableStatement(ts.visitNodes(node.modifiers, modifierVisitor, ts.isModifier), ts.createVariableDeclarationList([
+                ts.createVariableDeclaration(ts.getLocalName(node, /*allowComments*/ false, /*allowSourceMaps*/ true))
+            ], currentScope.kind === 274 /* SourceFile */ ? 0 /* None */ : 1 /* Let */));
+            ts.setOriginalNode(statement, node);
+            recordEmittedDeclarationInScope(node);
+            if (isFirstEmittedDeclarationInScope(node)) {
+                // Adjust the source map emit to match the old emitter.
+                if (node.kind === 238 /* EnumDeclaration */) {
+                    ts.setSourceMapRange(statement.declarationList, node);
+                }
+                else {
+                    ts.setSourceMapRange(statement, node);
+                }
+                // Trailing comments for module declaration should be emitted after the function closure
+                // instead of the variable statement:
+                //
+                //     /** Module comment*/
+                //     module m1 {
+                //         function foo4Export() {
+                //         }
+                //     } // trailing comment module
+                //
+                // Should emit:
+                //
+                //     /** Module comment*/
+                //     var m1;
+                //     (function (m1) {
+                //         function foo4Export() {
+                //         }
+                //     })(m1 || (m1 = {})); // trailing comment module
+                //
+                ts.setCommentRange(statement, node);
+                ts.setEmitFlags(statement, 1024 /* NoTrailingComments */ | 4194304 /* HasEndOfDeclarationMarker */);
+                statements.push(statement);
+                return true;
+            }
+            else {
+                // For an EnumDeclaration or ModuleDeclaration that merges with a preceeding
+                // declaration we do not emit a leading variable declaration. To preserve the
+                // begin/end semantics of the declararation and to properly handle exports
+                // we wrap the leading variable declaration in a `MergeDeclarationMarker`.
+                var mergeMarker = ts.createMergeDeclarationMarker(statement);
+                ts.setEmitFlags(mergeMarker, 1536 /* NoComments */ | 4194304 /* HasEndOfDeclarationMarker */);
+                statements.push(mergeMarker);
+                return false;
+            }
+        }
+        /**
+         * Visits a module declaration node.
+         *
+         * This function will be called any time a TypeScript namespace (ModuleDeclaration) is encountered.
+         *
+         * @param node The module declaration node.
+         */
+        function visitModuleDeclaration(node) {
+            if (!shouldEmitModuleDeclaration(node)) {
+                return ts.createNotEmittedStatement(node);
+            }
+            ts.Debug.assertNode(node.name, ts.isIdentifier, "A TypeScript namespace should have an Identifier name.");
+            enableSubstitutionForNamespaceExports();
+            var statements = [];
+            // We request to be advised when the printer is about to print this node. This allows
+            // us to set up the correct state for later substitutions.
+            var emitFlags = 2 /* AdviseOnEmitNode */;
+            // If needed, we should emit a variable declaration for the module. If we emit
+            // a leading variable declaration, we should not emit leading comments for the
+            // module body.
+            if (addVarForEnumOrModuleDeclaration(statements, node)) {
+                // We should still emit the comments if we are emitting a system module.
+                if (moduleKind !== ts.ModuleKind.System || currentScope !== currentSourceFile) {
+                    emitFlags |= 512 /* NoLeadingComments */;
+                }
+            }
+            // `parameterName` is the declaration name used inside of the namespace.
+            var parameterName = getNamespaceParameterName(node);
+            // `containerName` is the expression used inside of the namespace for exports.
+            var containerName = getNamespaceContainerName(node);
+            // `exportName` is the expression used within this node's container for any exported references.
+            var exportName = ts.hasModifier(node, 1 /* Export */)
+                ? ts.getExternalModuleOrNamespaceExportName(currentNamespaceContainerName, node, /*allowComments*/ false, /*allowSourceMaps*/ true)
+                : ts.getLocalName(node, /*allowComments*/ false, /*allowSourceMaps*/ true);
+            //  x || (x = {})
+            //  exports.x || (exports.x = {})
+            var moduleArg = ts.createLogicalOr(exportName, ts.createAssignment(exportName, ts.createObjectLiteral()));
+            if (hasNamespaceQualifiedExportName(node)) {
+                // `localName` is the expression used within this node's containing scope for any local references.
+                var localName = ts.getLocalName(node, /*allowComments*/ false, /*allowSourceMaps*/ true);
+                //  x = (exports.x || (exports.x = {}))
+                moduleArg = ts.createAssignment(localName, moduleArg);
+            }
+            //  (function (x_1) {
+            //      x_1.y = ...;
+            //  })(x || (x = {}));
+            var moduleStatement = ts.createStatement(ts.createCall(ts.createFunctionExpression(
+            /*modifiers*/ undefined, 
+            /*asteriskToken*/ undefined, 
+            /*name*/ undefined, 
+            /*typeParameters*/ undefined, [ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, parameterName)], 
+            /*type*/ undefined, transformModuleBody(node, containerName)), 
+            /*typeArguments*/ undefined, [moduleArg]));
+            ts.setOriginalNode(moduleStatement, node);
+            ts.setTextRange(moduleStatement, node);
+            ts.setEmitFlags(moduleStatement, emitFlags);
+            statements.push(moduleStatement);
+            // Add a DeclarationMarker for the namespace to preserve trailing comments and mark
+            // the end of the declaration.
+            statements.push(ts.createEndOfDeclarationMarker(node));
+            return statements;
+        }
+        /**
+         * Transforms the body of a module declaration.
+         *
+         * @param node The module declaration node.
+         */
+        function transformModuleBody(node, namespaceLocalName) {
+            var savedCurrentNamespaceContainerName = currentNamespaceContainerName;
+            var savedCurrentNamespace = currentNamespace;
+            var savedCurrentScopeFirstDeclarationsOfName = currentScopeFirstDeclarationsOfName;
+            currentNamespaceContainerName = namespaceLocalName;
+            currentNamespace = node;
+            currentScopeFirstDeclarationsOfName = undefined;
+            var statements = [];
+            startLexicalEnvironment();
+            var statementsLocation;
+            var blockLocation;
+            var body = node.body;
+            if (body.kind === 240 /* ModuleBlock */) {
+                saveStateAndInvoke(body, function (body) { return ts.addRange(statements, ts.visitNodes(body.statements, namespaceElementVisitor, ts.isStatement)); });
+                statementsLocation = body.statements;
+                blockLocation = body;
+            }
+            else {
+                var result = visitModuleDeclaration(body);
+                if (result) {
+                    if (ts.isArray(result)) {
+                        ts.addRange(statements, result);
+                    }
+                    else {
+                        statements.push(result);
+                    }
+                }
+                var moduleBlock = getInnerMostModuleDeclarationFromDottedModule(node).body;
+                statementsLocation = ts.moveRangePos(moduleBlock.statements, -1);
+            }
+            ts.prependStatements(statements, endLexicalEnvironment());
+            currentNamespaceContainerName = savedCurrentNamespaceContainerName;
+            currentNamespace = savedCurrentNamespace;
+            currentScopeFirstDeclarationsOfName = savedCurrentScopeFirstDeclarationsOfName;
+            var block = ts.createBlock(ts.setTextRange(ts.createNodeArray(statements), 
+            /*location*/ statementsLocation), 
+            /*multiLine*/ true);
+            ts.setTextRange(block, blockLocation);
+            // namespace hello.hi.world {
+            //      function foo() {}
+            //
+            //      // TODO, blah
+            // }
+            //
+            // should be emitted as
+            //
+            // var hello;
+            // (function (hello) {
+            //     var hi;
+            //     (function (hi) {
+            //         var world;
+            //         (function (world) {
+            //             function foo() { }
+            //             // TODO, blah
+            //         })(world = hi.world || (hi.world = {}));
+            //     })(hi = hello.hi || (hello.hi = {}));
+            // })(hello || (hello = {}));
+            // We only want to emit comment on the namespace which contains block body itself, not the containing namespaces.
+            if (body.kind !== 240 /* ModuleBlock */) {
+                ts.setEmitFlags(block, ts.getEmitFlags(block) | 1536 /* NoComments */);
+            }
+            return block;
+        }
+        function getInnerMostModuleDeclarationFromDottedModule(moduleDeclaration) {
+            if (moduleDeclaration.body.kind === 239 /* ModuleDeclaration */) {
+                var recursiveInnerModule = getInnerMostModuleDeclarationFromDottedModule(moduleDeclaration.body);
+                return recursiveInnerModule || moduleDeclaration.body;
+            }
+        }
+        /**
+         * Visits an import declaration, eliding it if it is not referenced.
+         *
+         * @param node The import declaration node.
+         */
+        function visitImportDeclaration(node) {
+            if (!node.importClause) {
+                // Do not elide a side-effect only import declaration.
+                //  import "foo";
+                return node;
+            }
+            // Elide the declaration if the import clause was elided.
+            var importClause = ts.visitNode(node.importClause, visitImportClause, ts.isImportClause);
+            return importClause
+                ? ts.updateImportDeclaration(node, 
+                /*decorators*/ undefined, 
+                /*modifiers*/ undefined, importClause, node.moduleSpecifier)
+                : undefined;
+        }
+        /**
+         * Visits an import clause, eliding it if it is not referenced.
+         *
+         * @param node The import clause node.
+         */
+        function visitImportClause(node) {
+            // Elide the import clause if we elide both its name and its named bindings.
+            var name = resolver.isReferencedAliasDeclaration(node) ? node.name : undefined;
+            var namedBindings = ts.visitNode(node.namedBindings, visitNamedImportBindings, ts.isNamedImportBindings);
+            return (name || namedBindings) ? ts.updateImportClause(node, name, namedBindings) : undefined;
+        }
+        /**
+         * Visits named import bindings, eliding it if it is not referenced.
+         *
+         * @param node The named import bindings node.
+         */
+        function visitNamedImportBindings(node) {
+            if (node.kind === 246 /* NamespaceImport */) {
+                // Elide a namespace import if it is not referenced.
+                return resolver.isReferencedAliasDeclaration(node) ? node : undefined;
+            }
+            else {
+                // Elide named imports if all of its import specifiers are elided.
+                var elements = ts.visitNodes(node.elements, visitImportSpecifier, ts.isImportSpecifier);
+                return ts.some(elements) ? ts.updateNamedImports(node, elements) : undefined;
+            }
+        }
+        /**
+         * Visits an import specifier, eliding it if it is not referenced.
+         *
+         * @param node The import specifier node.
+         */
+        function visitImportSpecifier(node) {
+            // Elide an import specifier if it is not referenced.
+            return resolver.isReferencedAliasDeclaration(node) ? node : undefined;
+        }
+        /**
+         * Visits an export assignment, eliding it if it does not contain a clause that resolves
+         * to a value.
+         *
+         * @param node The export assignment node.
+         */
+        function visitExportAssignment(node) {
+            // Elide the export assignment if it does not reference a value.
+            return resolver.isValueAliasDeclaration(node)
+                ? ts.visitEachChild(node, visitor, context)
+                : undefined;
+        }
+        /**
+         * Visits an export declaration, eliding it if it does not contain a clause that resolves
+         * to a value.
+         *
+         * @param node The export declaration node.
+         */
+        function visitExportDeclaration(node) {
+            if (!node.exportClause) {
+                // Elide a star export if the module it references does not export a value.
+                return compilerOptions.isolatedModules || resolver.moduleExportsSomeValue(node.moduleSpecifier) ? node : undefined;
+            }
+            if (!resolver.isValueAliasDeclaration(node)) {
+                // Elide the export declaration if it does not export a value.
+                return undefined;
+            }
+            // Elide the export declaration if all of its named exports are elided.
+            var exportClause = ts.visitNode(node.exportClause, visitNamedExports, ts.isNamedExports);
+            return exportClause
+                ? ts.updateExportDeclaration(node, 
+                /*decorators*/ undefined, 
+                /*modifiers*/ undefined, exportClause, node.moduleSpecifier)
+                : undefined;
+        }
+        /**
+         * Visits named exports, eliding it if it does not contain an export specifier that
+         * resolves to a value.
+         *
+         * @param node The named exports node.
+         */
+        function visitNamedExports(node) {
+            // Elide the named exports if all of its export specifiers were elided.
+            var elements = ts.visitNodes(node.elements, visitExportSpecifier, ts.isExportSpecifier);
+            return ts.some(elements) ? ts.updateNamedExports(node, elements) : undefined;
+        }
+        /**
+         * Visits an export specifier, eliding it if it does not resolve to a value.
+         *
+         * @param node The export specifier node.
+         */
+        function visitExportSpecifier(node) {
+            // Elide an export specifier if it does not reference a value.
+            return resolver.isValueAliasDeclaration(node) ? node : undefined;
+        }
+        /**
+         * Determines whether to emit an import equals declaration.
+         *
+         * @param node The import equals declaration node.
+         */
+        function shouldEmitImportEqualsDeclaration(node) {
+            // preserve old compiler's behavior: emit 'var' for import declaration (even if we do not consider them referenced) when
+            // - current file is not external module
+            // - import declaration is top level and target is value imported by entity name
+            return resolver.isReferencedAliasDeclaration(node)
+                || (!ts.isExternalModule(currentSourceFile)
+                    && resolver.isTopLevelValueImportEqualsWithEntityName(node));
+        }
+        /**
+         * Visits an import equals declaration.
+         *
+         * @param node The import equals declaration node.
+         */
+        function visitImportEqualsDeclaration(node) {
+            if (ts.isExternalModuleImportEqualsDeclaration(node)) {
+                // Elide external module `import=` if it is not referenced.
+                return resolver.isReferencedAliasDeclaration(node)
+                    ? ts.visitEachChild(node, visitor, context)
+                    : undefined;
+            }
+            if (!shouldEmitImportEqualsDeclaration(node)) {
+                return undefined;
+            }
+            var moduleReference = ts.createExpressionFromEntityName(node.moduleReference);
+            ts.setEmitFlags(moduleReference, 1536 /* NoComments */ | 2048 /* NoNestedComments */);
+            if (isNamedExternalModuleExport(node) || !isExportOfNamespace(node)) {
+                //  export var ${name} = ${moduleReference};
+                //  var ${name} = ${moduleReference};
+                return ts.setOriginalNode(ts.setTextRange(ts.createVariableStatement(ts.visitNodes(node.modifiers, modifierVisitor, ts.isModifier), ts.createVariableDeclarationList([
+                    ts.setOriginalNode(ts.createVariableDeclaration(node.name, 
+                    /*type*/ undefined, moduleReference), node)
+                ])), node), node);
+            }
+            else {
+                // exports.${name} = ${moduleReference};
+                return ts.setOriginalNode(createNamespaceExport(node.name, moduleReference, node), node);
+            }
+        }
+        /**
+         * Gets a value indicating whether the node is exported from a namespace.
+         *
+         * @param node The node to test.
+         */
+        function isExportOfNamespace(node) {
+            return currentNamespace !== undefined && ts.hasModifier(node, 1 /* Export */);
+        }
+        /**
+         * Gets a value indicating whether the node is exported from an external module.
+         *
+         * @param node The node to test.
+         */
+        function isExternalModuleExport(node) {
+            return currentNamespace === undefined && ts.hasModifier(node, 1 /* Export */);
+        }
+        /**
+         * Gets a value indicating whether the node is a named export from an external module.
+         *
+         * @param node The node to test.
+         */
+        function isNamedExternalModuleExport(node) {
+            return isExternalModuleExport(node)
+                && !ts.hasModifier(node, 512 /* Default */);
+        }
+        /**
+         * Gets a value indicating whether the node is the default export of an external module.
+         *
+         * @param node The node to test.
+         */
+        function isDefaultExternalModuleExport(node) {
+            return isExternalModuleExport(node)
+                && ts.hasModifier(node, 512 /* Default */);
+        }
+        /**
+         * Creates a statement for the provided expression. This is used in calls to `map`.
+         */
+        function expressionToStatement(expression) {
+            return ts.createStatement(expression);
+        }
+        function addExportMemberAssignment(statements, node) {
+            var expression = ts.createAssignment(ts.getExternalModuleOrNamespaceExportName(currentNamespaceContainerName, node, /*allowComments*/ false, /*allowSourceMaps*/ true), ts.getLocalName(node));
+            ts.setSourceMapRange(expression, ts.createRange(node.name ? node.name.pos : node.pos, node.end));
+            var statement = ts.createStatement(expression);
+            ts.setSourceMapRange(statement, ts.createRange(-1, node.end));
+            statements.push(statement);
+        }
+        function createNamespaceExport(exportName, exportValue, location) {
+            return ts.setTextRange(ts.createStatement(ts.createAssignment(ts.getNamespaceMemberName(currentNamespaceContainerName, exportName, /*allowComments*/ false, /*allowSourceMaps*/ true), exportValue)), location);
+        }
+        function createNamespaceExportExpression(exportName, exportValue, location) {
+            return ts.setTextRange(ts.createAssignment(getNamespaceMemberNameWithSourceMapsAndWithoutComments(exportName), exportValue), location);
+        }
+        function getNamespaceMemberNameWithSourceMapsAndWithoutComments(name) {
+            return ts.getNamespaceMemberName(currentNamespaceContainerName, name, /*allowComments*/ false, /*allowSourceMaps*/ true);
+        }
+        /**
+         * Gets the declaration name used inside of a namespace or enum.
+         */
+        function getNamespaceParameterName(node) {
+            var name = ts.getGeneratedNameForNode(node);
+            ts.setSourceMapRange(name, node.name);
+            return name;
+        }
+        /**
+         * Gets the expression used to refer to a namespace or enum within the body
+         * of its declaration.
+         */
+        function getNamespaceContainerName(node) {
+            return ts.getGeneratedNameForNode(node);
+        }
+        /**
+         * Gets a local alias for a class declaration if it is a decorated class with an internal
+         * reference to the static side of the class. This is necessary to avoid issues with
+         * double-binding semantics for the class name.
+         */
+        function getClassAliasIfNeeded(node) {
+            if (resolver.getNodeCheckFlags(node) & 8388608 /* ClassWithConstructorReference */) {
+                enableSubstitutionForClassAliases();
+                var classAlias = ts.createUniqueName(node.name && !ts.isGeneratedIdentifier(node.name) ? ts.idText(node.name) : "default");
+                classAliases[ts.getOriginalNodeId(node)] = classAlias;
+                hoistVariableDeclaration(classAlias);
+                return classAlias;
+            }
+        }
+        function getClassPrototype(node) {
+            return ts.createPropertyAccess(ts.getDeclarationName(node), "prototype");
+        }
+        function getClassMemberPrefix(node, member) {
+            return ts.hasModifier(member, 32 /* Static */)
+                ? ts.getDeclarationName(node)
+                : getClassPrototype(node);
+        }
+        function enableSubstitutionForNonQualifiedEnumMembers() {
+            if ((enabledSubstitutions & 8 /* NonQualifiedEnumMembers */) === 0) {
+                enabledSubstitutions |= 8 /* NonQualifiedEnumMembers */;
+                context.enableSubstitution(71 /* Identifier */);
+            }
+        }
+        function enableSubstitutionForClassAliases() {
+            if ((enabledSubstitutions & 1 /* ClassAliases */) === 0) {
+                enabledSubstitutions |= 1 /* ClassAliases */;
+                // We need to enable substitutions for identifiers. This allows us to
+                // substitute class names inside of a class declaration.
+                context.enableSubstitution(71 /* Identifier */);
+                // Keep track of class aliases.
+                classAliases = [];
+            }
+        }
+        function enableSubstitutionForNamespaceExports() {
+            if ((enabledSubstitutions & 2 /* NamespaceExports */) === 0) {
+                enabledSubstitutions |= 2 /* NamespaceExports */;
+                // We need to enable substitutions for identifiers and shorthand property assignments. This allows us to
+                // substitute the names of exported members of a namespace.
+                context.enableSubstitution(71 /* Identifier */);
+                context.enableSubstitution(271 /* ShorthandPropertyAssignment */);
+                // We need to be notified when entering and exiting namespaces.
+                context.enableEmitNotification(239 /* ModuleDeclaration */);
+            }
+        }
+        function isTransformedModuleDeclaration(node) {
+            return ts.getOriginalNode(node).kind === 239 /* ModuleDeclaration */;
+        }
+        function isTransformedEnumDeclaration(node) {
+            return ts.getOriginalNode(node).kind === 238 /* EnumDeclaration */;
+        }
+        /**
+         * Hook for node emit.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to emit.
+         * @param emit A callback used to emit the node in the printer.
+         */
+        function onEmitNode(hint, node, emitCallback) {
+            var savedApplicableSubstitutions = applicableSubstitutions;
+            var savedCurrentSourceFile = currentSourceFile;
+            if (ts.isSourceFile(node)) {
+                currentSourceFile = node;
+            }
+            if (enabledSubstitutions & 2 /* NamespaceExports */ && isTransformedModuleDeclaration(node)) {
+                applicableSubstitutions |= 2 /* NamespaceExports */;
+            }
+            if (enabledSubstitutions & 8 /* NonQualifiedEnumMembers */ && isTransformedEnumDeclaration(node)) {
+                applicableSubstitutions |= 8 /* NonQualifiedEnumMembers */;
+            }
+            previousOnEmitNode(hint, node, emitCallback);
+            applicableSubstitutions = savedApplicableSubstitutions;
+            currentSourceFile = savedCurrentSourceFile;
+        }
+        /**
+         * Hooks node substitutions.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to substitute.
+         */
+        function onSubstituteNode(hint, node) {
+            node = previousOnSubstituteNode(hint, node);
+            if (hint === 1 /* Expression */) {
+                return substituteExpression(node);
+            }
+            else if (ts.isShorthandPropertyAssignment(node)) {
+                return substituteShorthandPropertyAssignment(node);
+            }
+            return node;
+        }
+        function substituteShorthandPropertyAssignment(node) {
+            if (enabledSubstitutions & 2 /* NamespaceExports */) {
+                var name = node.name;
+                var exportedName = trySubstituteNamespaceExportedName(name);
+                if (exportedName) {
+                    // A shorthand property with an assignment initializer is probably part of a
+                    // destructuring assignment
+                    if (node.objectAssignmentInitializer) {
+                        var initializer = ts.createAssignment(exportedName, node.objectAssignmentInitializer);
+                        return ts.setTextRange(ts.createPropertyAssignment(name, initializer), node);
+                    }
+                    return ts.setTextRange(ts.createPropertyAssignment(name, exportedName), node);
+                }
+            }
+            return node;
+        }
+        function substituteExpression(node) {
+            switch (node.kind) {
+                case 71 /* Identifier */:
+                    return substituteExpressionIdentifier(node);
+                case 185 /* PropertyAccessExpression */:
+                    return substitutePropertyAccessExpression(node);
+                case 186 /* ElementAccessExpression */:
+                    return substituteElementAccessExpression(node);
+            }
+            return node;
+        }
+        function substituteExpressionIdentifier(node) {
+            return trySubstituteClassAlias(node)
+                || trySubstituteNamespaceExportedName(node)
+                || node;
+        }
+        function trySubstituteClassAlias(node) {
+            if (enabledSubstitutions & 1 /* ClassAliases */) {
+                if (resolver.getNodeCheckFlags(node) & 16777216 /* ConstructorReferenceInClass */) {
+                    // Due to the emit for class decorators, any reference to the class from inside of the class body
+                    // must instead be rewritten to point to a temporary variable to avoid issues with the double-bind
+                    // behavior of class names in ES6.
+                    // Also, when emitting statics for class expressions, we must substitute a class alias for
+                    // constructor references in static property initializers.
+                    var declaration = resolver.getReferencedValueDeclaration(node);
+                    if (declaration) {
+                        var classAlias = classAliases[declaration.id]; // TODO: GH#18217
+                        if (classAlias) {
+                            var clone_1 = ts.getSynthesizedClone(classAlias);
+                            ts.setSourceMapRange(clone_1, node);
+                            ts.setCommentRange(clone_1, node);
+                            return clone_1;
+                        }
+                    }
+                }
+            }
+            return undefined;
+        }
+        function trySubstituteNamespaceExportedName(node) {
+            // If this is explicitly a local name, do not substitute.
+            if (enabledSubstitutions & applicableSubstitutions && !ts.isGeneratedIdentifier(node) && !ts.isLocalName(node)) {
+                // If we are nested within a namespace declaration, we may need to qualifiy
+                // an identifier that is exported from a merged namespace.
+                var container = resolver.getReferencedExportContainer(node, /*prefixLocals*/ false);
+                if (container && container.kind !== 274 /* SourceFile */) {
+                    var substitute = (applicableSubstitutions & 2 /* NamespaceExports */ && container.kind === 239 /* ModuleDeclaration */) ||
+                        (applicableSubstitutions & 8 /* NonQualifiedEnumMembers */ && container.kind === 238 /* EnumDeclaration */);
+                    if (substitute) {
+                        return ts.setTextRange(ts.createPropertyAccess(ts.getGeneratedNameForNode(container), node), 
+                        /*location*/ node);
+                    }
+                }
+            }
+            return undefined;
+        }
+        function substitutePropertyAccessExpression(node) {
+            return substituteConstantValue(node);
+        }
+        function substituteElementAccessExpression(node) {
+            return substituteConstantValue(node);
+        }
+        function substituteConstantValue(node) {
+            var constantValue = tryGetConstEnumValue(node);
+            if (constantValue !== undefined) {
+                // track the constant value on the node for the printer in needsDotDotForPropertyAccess
+                ts.setConstantValue(node, constantValue);
+                var substitute = ts.createLiteral(constantValue);
+                if (!compilerOptions.removeComments) {
+                    var propertyName = ts.isPropertyAccessExpression(node)
+                        ? ts.declarationNameToString(node.name)
+                        : ts.getTextOfNode(node.argumentExpression);
+                    ts.addSyntheticTrailingComment(substitute, 3 /* MultiLineCommentTrivia */, " " + propertyName + " ");
+                }
+                return substitute;
+            }
+            return node;
+        }
+        function tryGetConstEnumValue(node) {
+            if (compilerOptions.isolatedModules) {
+                return undefined;
+            }
+            return ts.isPropertyAccessExpression(node) || ts.isElementAccessExpression(node) ? resolver.getConstantValue(node) : undefined;
+        }
+    }
+    ts.transformTypeScript = transformTypeScript;
+    function createDecorateHelper(context, decoratorExpressions, target, memberName, descriptor, location) {
+        var argumentsArray = [];
+        argumentsArray.push(ts.createArrayLiteral(decoratorExpressions, /*multiLine*/ true));
+        argumentsArray.push(target);
+        if (memberName) {
+            argumentsArray.push(memberName);
+            if (descriptor) {
+                argumentsArray.push(descriptor);
+            }
+        }
+        context.requestEmitHelper(decorateHelper);
+        return ts.setTextRange(ts.createCall(ts.getHelperName("__decorate"), 
+        /*typeArguments*/ undefined, argumentsArray), location);
+    }
+    var decorateHelper = {
+        name: "typescript:decorate",
+        scoped: false,
+        priority: 2,
+        text: "\n            var __decorate = (this && this.__decorate) || function (decorators, target, key, desc) {\n                var c = arguments.length, r = c < 3 ? target : desc === null ? desc = Object.getOwnPropertyDescriptor(target, key) : desc, d;\n                if (typeof Reflect === \"object\" && typeof Reflect.decorate === \"function\") r = Reflect.decorate(decorators, target, key, desc);\n                else for (var i = decorators.length - 1; i >= 0; i--) if (d = decorators[i]) r = (c < 3 ? d(r) : c > 3 ? d(target, key, r) : d(target, key)) || r;\n                return c > 3 && r && Object.defineProperty(target, key, r), r;\n            };"
+    };
+    function createMetadataHelper(context, metadataKey, metadataValue) {
+        context.requestEmitHelper(metadataHelper);
+        return ts.createCall(ts.getHelperName("__metadata"), 
+        /*typeArguments*/ undefined, [
+            ts.createLiteral(metadataKey),
+            metadataValue
+        ]);
+    }
+    var metadataHelper = {
+        name: "typescript:metadata",
+        scoped: false,
+        priority: 3,
+        text: "\n            var __metadata = (this && this.__metadata) || function (k, v) {\n                if (typeof Reflect === \"object\" && typeof Reflect.metadata === \"function\") return Reflect.metadata(k, v);\n            };"
+    };
+    function createParamHelper(context, expression, parameterOffset, location) {
+        context.requestEmitHelper(paramHelper);
+        return ts.setTextRange(ts.createCall(ts.getHelperName("__param"), 
+        /*typeArguments*/ undefined, [
+            ts.createLiteral(parameterOffset),
+            expression
+        ]), location);
+    }
+    var paramHelper = {
+        name: "typescript:param",
+        scoped: false,
+        priority: 4,
+        text: "\n            var __param = (this && this.__param) || function (paramIndex, decorator) {\n                return function (target, key) { decorator(target, key, paramIndex); }\n            };"
+    };
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    var ES2017SubstitutionFlags;
+    (function (ES2017SubstitutionFlags) {
+        /** Enables substitutions for async methods with `super` calls. */
+        ES2017SubstitutionFlags[ES2017SubstitutionFlags["AsyncMethodsWithSuper"] = 1] = "AsyncMethodsWithSuper";
+    })(ES2017SubstitutionFlags || (ES2017SubstitutionFlags = {}));
+    function transformES2017(context) {
+        var resumeLexicalEnvironment = context.resumeLexicalEnvironment, endLexicalEnvironment = context.endLexicalEnvironment, hoistVariableDeclaration = context.hoistVariableDeclaration;
+        var resolver = context.getEmitResolver();
+        var compilerOptions = context.getCompilerOptions();
+        var languageVersion = ts.getEmitScriptTarget(compilerOptions);
+        /**
+         * Keeps track of whether expression substitution has been enabled for specific edge cases.
+         * They are persisted between each SourceFile transformation and should not be reset.
+         */
+        var enabledSubstitutions;
+        /**
+         * This keeps track of containers where `super` is valid, for use with
+         * just-in-time substitution for `super` expressions inside of async methods.
+         */
+        var enclosingSuperContainerFlags = 0;
+        var enclosingFunctionParameterNames;
+        // Save the previous transformation hooks.
+        var previousOnEmitNode = context.onEmitNode;
+        var previousOnSubstituteNode = context.onSubstituteNode;
+        // Set new transformation hooks.
+        context.onEmitNode = onEmitNode;
+        context.onSubstituteNode = onSubstituteNode;
+        return ts.chainBundle(transformSourceFile);
+        function transformSourceFile(node) {
+            if (node.isDeclarationFile) {
+                return node;
+            }
+            var visited = ts.visitEachChild(node, visitor, context);
+            ts.addEmitHelpers(visited, context.readEmitHelpers());
+            return visited;
+        }
+        function visitor(node) {
+            if ((node.transformFlags & 16 /* ContainsES2017 */) === 0) {
+                return node;
+            }
+            switch (node.kind) {
+                case 120 /* AsyncKeyword */:
+                    // ES2017 async modifier should be elided for targets < ES2017
+                    return undefined;
+                case 197 /* AwaitExpression */:
+                    return visitAwaitExpression(node);
+                case 154 /* MethodDeclaration */:
+                    return visitMethodDeclaration(node);
+                case 234 /* FunctionDeclaration */:
+                    return visitFunctionDeclaration(node);
+                case 192 /* FunctionExpression */:
+                    return visitFunctionExpression(node);
+                case 193 /* ArrowFunction */:
+                    return visitArrowFunction(node);
+                default:
+                    return ts.visitEachChild(node, visitor, context);
+            }
+        }
+        function asyncBodyVisitor(node) {
+            if (ts.isNodeWithPossibleHoistedDeclaration(node)) {
+                switch (node.kind) {
+                    case 214 /* VariableStatement */:
+                        return visitVariableStatementInAsyncBody(node);
+                    case 220 /* ForStatement */:
+                        return visitForStatementInAsyncBody(node);
+                    case 221 /* ForInStatement */:
+                        return visitForInStatementInAsyncBody(node);
+                    case 222 /* ForOfStatement */:
+                        return visitForOfStatementInAsyncBody(node);
+                    case 269 /* CatchClause */:
+                        return visitCatchClauseInAsyncBody(node);
+                    case 213 /* Block */:
+                    case 227 /* SwitchStatement */:
+                    case 241 /* CaseBlock */:
+                    case 266 /* CaseClause */:
+                    case 267 /* DefaultClause */:
+                    case 230 /* TryStatement */:
+                    case 218 /* DoStatement */:
+                    case 219 /* WhileStatement */:
+                    case 217 /* IfStatement */:
+                    case 226 /* WithStatement */:
+                    case 228 /* LabeledStatement */:
+                        return ts.visitEachChild(node, asyncBodyVisitor, context);
+                    default:
+                        return ts.Debug.assertNever(node, "Unhandled node.");
+                }
+            }
+            return visitor(node);
+        }
+        function visitCatchClauseInAsyncBody(node) {
+            var catchClauseNames = ts.createUnderscoreEscapedMap();
+            recordDeclarationName(node.variableDeclaration, catchClauseNames); // TODO: GH#18217
+            // names declared in a catch variable are block scoped
+            var catchClauseUnshadowedNames;
+            catchClauseNames.forEach(function (_, escapedName) {
+                if (enclosingFunctionParameterNames.has(escapedName)) {
+                    if (!catchClauseUnshadowedNames) {
+                        catchClauseUnshadowedNames = ts.cloneMap(enclosingFunctionParameterNames);
+                    }
+                    catchClauseUnshadowedNames.delete(escapedName);
+                }
+            });
+            if (catchClauseUnshadowedNames) {
+                var savedEnclosingFunctionParameterNames = enclosingFunctionParameterNames;
+                enclosingFunctionParameterNames = catchClauseUnshadowedNames;
+                var result = ts.visitEachChild(node, asyncBodyVisitor, context);
+                enclosingFunctionParameterNames = savedEnclosingFunctionParameterNames;
+                return result;
+            }
+            else {
+                return ts.visitEachChild(node, asyncBodyVisitor, context);
+            }
+        }
+        function visitVariableStatementInAsyncBody(node) {
+            if (isVariableDeclarationListWithCollidingName(node.declarationList)) {
+                var expression = visitVariableDeclarationListWithCollidingNames(node.declarationList, /*hasReceiver*/ false);
+                return expression ? ts.createStatement(expression) : undefined;
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitForInStatementInAsyncBody(node) {
+            return ts.updateForIn(node, isVariableDeclarationListWithCollidingName(node.initializer)
+                ? visitVariableDeclarationListWithCollidingNames(node.initializer, /*hasReceiver*/ true)
+                : ts.visitNode(node.initializer, visitor, ts.isForInitializer), ts.visitNode(node.expression, visitor, ts.isExpression), ts.visitNode(node.statement, asyncBodyVisitor, ts.isStatement, ts.liftToBlock));
+        }
+        function visitForOfStatementInAsyncBody(node) {
+            return ts.updateForOf(node, ts.visitNode(node.awaitModifier, visitor, ts.isToken), isVariableDeclarationListWithCollidingName(node.initializer)
+                ? visitVariableDeclarationListWithCollidingNames(node.initializer, /*hasReceiver*/ true)
+                : ts.visitNode(node.initializer, visitor, ts.isForInitializer), ts.visitNode(node.expression, visitor, ts.isExpression), ts.visitNode(node.statement, asyncBodyVisitor, ts.isStatement, ts.liftToBlock));
+        }
+        function visitForStatementInAsyncBody(node) {
+            var initializer = node.initializer; // TODO: GH#18217
+            return ts.updateFor(node, isVariableDeclarationListWithCollidingName(initializer)
+                ? visitVariableDeclarationListWithCollidingNames(initializer, /*hasReceiver*/ false)
+                : ts.visitNode(node.initializer, visitor, ts.isForInitializer), ts.visitNode(node.condition, visitor, ts.isExpression), ts.visitNode(node.incrementor, visitor, ts.isExpression), ts.visitNode(node.statement, asyncBodyVisitor, ts.isStatement, ts.liftToBlock));
+        }
+        /**
+         * Visits an AwaitExpression node.
+         *
+         * This function will be called any time a ES2017 await expression is encountered.
+         *
+         * @param node The node to visit.
+         */
+        function visitAwaitExpression(node) {
+            return ts.setOriginalNode(ts.setTextRange(ts.createYield(
+            /*asteriskToken*/ undefined, ts.visitNode(node.expression, visitor, ts.isExpression)), node), node);
+        }
+        /**
+         * Visits a MethodDeclaration node.
+         *
+         * This function will be called when one of the following conditions are met:
+         * - The node is marked as async
+         *
+         * @param node The node to visit.
+         */
+        function visitMethodDeclaration(node) {
+            return ts.updateMethod(node, 
+            /*decorators*/ undefined, ts.visitNodes(node.modifiers, visitor, ts.isModifier), node.asteriskToken, node.name, 
+            /*questionToken*/ undefined, 
+            /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, ts.getFunctionFlags(node) & 2 /* Async */
+                ? transformAsyncFunctionBody(node)
+                : ts.visitFunctionBody(node.body, visitor, context));
+        }
+        /**
+         * Visits a FunctionDeclaration node.
+         *
+         * This function will be called when one of the following conditions are met:
+         * - The node is marked async
+         *
+         * @param node The node to visit.
+         */
+        function visitFunctionDeclaration(node) {
+            return ts.updateFunctionDeclaration(node, 
+            /*decorators*/ undefined, ts.visitNodes(node.modifiers, visitor, ts.isModifier), node.asteriskToken, node.name, 
+            /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, ts.getFunctionFlags(node) & 2 /* Async */
+                ? transformAsyncFunctionBody(node)
+                : ts.visitFunctionBody(node.body, visitor, context));
+        }
+        /**
+         * Visits a FunctionExpression node.
+         *
+         * This function will be called when one of the following conditions are met:
+         * - The node is marked async
+         *
+         * @param node The node to visit.
+         */
+        function visitFunctionExpression(node) {
+            return ts.updateFunctionExpression(node, ts.visitNodes(node.modifiers, visitor, ts.isModifier), node.asteriskToken, node.name, 
+            /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, ts.getFunctionFlags(node) & 2 /* Async */
+                ? transformAsyncFunctionBody(node)
+                : ts.visitFunctionBody(node.body, visitor, context));
+        }
+        /**
+         * Visits an ArrowFunction.
+         *
+         * This function will be called when one of the following conditions are met:
+         * - The node is marked async
+         *
+         * @param node The node to visit.
+         */
+        function visitArrowFunction(node) {
+            return ts.updateArrowFunction(node, ts.visitNodes(node.modifiers, visitor, ts.isModifier), 
+            /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, node.equalsGreaterThanToken, ts.getFunctionFlags(node) & 2 /* Async */
+                ? transformAsyncFunctionBody(node)
+                : ts.visitFunctionBody(node.body, visitor, context));
+        }
+        function recordDeclarationName(_a, names) {
+            var name = _a.name;
+            if (ts.isIdentifier(name)) {
+                names.set(name.escapedText, true);
+            }
+            else {
+                for (var _i = 0, _b = name.elements; _i < _b.length; _i++) {
+                    var element = _b[_i];
+                    if (!ts.isOmittedExpression(element)) {
+                        recordDeclarationName(element, names);
+                    }
+                }
+            }
+        }
+        function isVariableDeclarationListWithCollidingName(node) {
+            return !!node
+                && ts.isVariableDeclarationList(node)
+                && !(node.flags & 3 /* BlockScoped */)
+                && node.declarations.some(collidesWithParameterName);
+        }
+        function visitVariableDeclarationListWithCollidingNames(node, hasReceiver) {
+            hoistVariableDeclarationList(node);
+            var variables = ts.getInitializedVariables(node);
+            if (variables.length === 0) {
+                if (hasReceiver) {
+                    return ts.visitNode(ts.convertToAssignmentElementTarget(node.declarations[0].name), visitor, ts.isExpression);
+                }
+                return undefined;
+            }
+            return ts.inlineExpressions(ts.map(variables, transformInitializedVariable));
+        }
+        function hoistVariableDeclarationList(node) {
+            ts.forEach(node.declarations, hoistVariable);
+        }
+        function hoistVariable(_a) {
+            var name = _a.name;
+            if (ts.isIdentifier(name)) {
+                hoistVariableDeclaration(name);
+            }
+            else {
+                for (var _i = 0, _b = name.elements; _i < _b.length; _i++) {
+                    var element = _b[_i];
+                    if (!ts.isOmittedExpression(element)) {
+                        hoistVariable(element);
+                    }
+                }
+            }
+        }
+        function transformInitializedVariable(node) {
+            var converted = ts.setSourceMapRange(ts.createAssignment(ts.convertToAssignmentElementTarget(node.name), node.initializer), node);
+            return ts.visitNode(converted, visitor, ts.isExpression);
+        }
+        function collidesWithParameterName(_a) {
+            var name = _a.name;
+            if (ts.isIdentifier(name)) {
+                return enclosingFunctionParameterNames.has(name.escapedText);
+            }
+            else {
+                for (var _i = 0, _b = name.elements; _i < _b.length; _i++) {
+                    var element = _b[_i];
+                    if (!ts.isOmittedExpression(element) && collidesWithParameterName(element)) {
+                        return true;
+                    }
+                }
+            }
+            return false;
+        }
+        function transformAsyncFunctionBody(node) {
+            resumeLexicalEnvironment();
+            var original = ts.getOriginalNode(node, ts.isFunctionLike);
+            var nodeType = original.type;
+            var promiseConstructor = languageVersion < 2 /* ES2015 */ ? getPromiseConstructor(nodeType) : undefined;
+            var isArrowFunction = node.kind === 193 /* ArrowFunction */;
+            var hasLexicalArguments = (resolver.getNodeCheckFlags(node) & 8192 /* CaptureArguments */) !== 0;
+            // An async function is emit as an outer function that calls an inner
+            // generator function. To preserve lexical bindings, we pass the current
+            // `this` and `arguments` objects to `__awaiter`. The generator function
+            // passed to `__awaiter` is executed inside of the callback to the
+            // promise constructor.
+            var savedEnclosingFunctionParameterNames = enclosingFunctionParameterNames;
+            enclosingFunctionParameterNames = ts.createUnderscoreEscapedMap();
+            for (var _i = 0, _a = node.parameters; _i < _a.length; _i++) {
+                var parameter = _a[_i];
+                recordDeclarationName(parameter, enclosingFunctionParameterNames);
+            }
+            var result;
+            if (!isArrowFunction) {
+                var statements = [];
+                var statementOffset = ts.addPrologue(statements, node.body.statements, /*ensureUseStrict*/ false, visitor);
+                statements.push(ts.createReturn(createAwaiterHelper(context, hasLexicalArguments, promiseConstructor, transformAsyncFunctionBodyWorker(node.body, statementOffset))));
+                ts.prependStatements(statements, endLexicalEnvironment());
+                var block = ts.createBlock(statements, /*multiLine*/ true);
+                ts.setTextRange(block, node.body);
+                // Minor optimization, emit `_super` helper to capture `super` access in an arrow.
+                // This step isn't needed if we eventually transform this to ES5.
+                if (languageVersion >= 2 /* ES2015 */) {
+                    if (resolver.getNodeCheckFlags(node) & 4096 /* AsyncMethodWithSuperBinding */) {
+                        enableSubstitutionForAsyncMethodsWithSuper();
+                        ts.addEmitHelper(block, ts.advancedAsyncSuperHelper);
+                    }
+                    else if (resolver.getNodeCheckFlags(node) & 2048 /* AsyncMethodWithSuper */) {
+                        enableSubstitutionForAsyncMethodsWithSuper();
+                        ts.addEmitHelper(block, ts.asyncSuperHelper);
+                    }
+                }
+                result = block;
+            }
+            else {
+                var expression = createAwaiterHelper(context, hasLexicalArguments, promiseConstructor, transformAsyncFunctionBodyWorker(node.body));
+                var declarations = endLexicalEnvironment();
+                if (ts.some(declarations)) {
+                    var block = ts.convertToFunctionBody(expression);
+                    result = ts.updateBlock(block, ts.setTextRange(ts.createNodeArray(ts.concatenate(declarations, block.statements)), block.statements));
+                }
+                else {
+                    result = expression;
+                }
+            }
+            enclosingFunctionParameterNames = savedEnclosingFunctionParameterNames;
+            return result;
+        }
+        function transformAsyncFunctionBodyWorker(body, start) {
+            if (ts.isBlock(body)) {
+                return ts.updateBlock(body, ts.visitNodes(body.statements, asyncBodyVisitor, ts.isStatement, start));
+            }
+            else {
+                return ts.convertToFunctionBody(ts.visitNode(body, asyncBodyVisitor, ts.isConciseBody));
+            }
+        }
+        function getPromiseConstructor(type) {
+            var typeName = type && ts.getEntityNameFromTypeNode(type);
+            if (typeName && ts.isEntityName(typeName)) {
+                var serializationKind = resolver.getTypeReferenceSerializationKind(typeName);
+                if (serializationKind === ts.TypeReferenceSerializationKind.TypeWithConstructSignatureAndValue
+                    || serializationKind === ts.TypeReferenceSerializationKind.Unknown) {
+                    return typeName;
+                }
+            }
+            return undefined;
+        }
+        function enableSubstitutionForAsyncMethodsWithSuper() {
+            if ((enabledSubstitutions & 1 /* AsyncMethodsWithSuper */) === 0) {
+                enabledSubstitutions |= 1 /* AsyncMethodsWithSuper */;
+                // We need to enable substitutions for call, property access, and element access
+                // if we need to rewrite super calls.
+                context.enableSubstitution(187 /* CallExpression */);
+                context.enableSubstitution(185 /* PropertyAccessExpression */);
+                context.enableSubstitution(186 /* ElementAccessExpression */);
+                // We need to be notified when entering and exiting declarations that bind super.
+                context.enableEmitNotification(235 /* ClassDeclaration */);
+                context.enableEmitNotification(154 /* MethodDeclaration */);
+                context.enableEmitNotification(156 /* GetAccessor */);
+                context.enableEmitNotification(157 /* SetAccessor */);
+                context.enableEmitNotification(155 /* Constructor */);
+            }
+        }
+        /**
+         * Hook for node emit.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to emit.
+         * @param emit A callback used to emit the node in the printer.
+         */
+        function onEmitNode(hint, node, emitCallback) {
+            // If we need to support substitutions for `super` in an async method,
+            // we should track it here.
+            if (enabledSubstitutions & 1 /* AsyncMethodsWithSuper */ && isSuperContainer(node)) {
+                var superContainerFlags = resolver.getNodeCheckFlags(node) & (2048 /* AsyncMethodWithSuper */ | 4096 /* AsyncMethodWithSuperBinding */);
+                if (superContainerFlags !== enclosingSuperContainerFlags) {
+                    var savedEnclosingSuperContainerFlags = enclosingSuperContainerFlags;
+                    enclosingSuperContainerFlags = superContainerFlags;
+                    previousOnEmitNode(hint, node, emitCallback);
+                    enclosingSuperContainerFlags = savedEnclosingSuperContainerFlags;
+                    return;
+                }
+            }
+            previousOnEmitNode(hint, node, emitCallback);
+        }
+        /**
+         * Hooks node substitutions.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to substitute.
+         */
+        function onSubstituteNode(hint, node) {
+            node = previousOnSubstituteNode(hint, node);
+            if (hint === 1 /* Expression */ && enclosingSuperContainerFlags) {
+                return substituteExpression(node);
+            }
+            return node;
+        }
+        function substituteExpression(node) {
+            switch (node.kind) {
+                case 185 /* PropertyAccessExpression */:
+                    return substitutePropertyAccessExpression(node);
+                case 186 /* ElementAccessExpression */:
+                    return substituteElementAccessExpression(node);
+                case 187 /* CallExpression */:
+                    return substituteCallExpression(node);
+            }
+            return node;
+        }
+        function substitutePropertyAccessExpression(node) {
+            if (node.expression.kind === 97 /* SuperKeyword */) {
+                return createSuperAccessInAsyncMethod(ts.createLiteral(ts.idText(node.name)), node);
+            }
+            return node;
+        }
+        function substituteElementAccessExpression(node) {
+            if (node.expression.kind === 97 /* SuperKeyword */) {
+                return createSuperAccessInAsyncMethod(node.argumentExpression, node);
+            }
+            return node;
+        }
+        function substituteCallExpression(node) {
+            var expression = node.expression;
+            if (ts.isSuperProperty(expression)) {
+                var argumentExpression = ts.isPropertyAccessExpression(expression)
+                    ? substitutePropertyAccessExpression(expression)
+                    : substituteElementAccessExpression(expression);
+                return ts.createCall(ts.createPropertyAccess(argumentExpression, "call"), 
+                /*typeArguments*/ undefined, [
+                    ts.createThis()
+                ].concat(node.arguments));
+            }
+            return node;
+        }
+        function isSuperContainer(node) {
+            var kind = node.kind;
+            return kind === 235 /* ClassDeclaration */
+                || kind === 155 /* Constructor */
+                || kind === 154 /* MethodDeclaration */
+                || kind === 156 /* GetAccessor */
+                || kind === 157 /* SetAccessor */;
+        }
+        function createSuperAccessInAsyncMethod(argumentExpression, location) {
+            if (enclosingSuperContainerFlags & 4096 /* AsyncMethodWithSuperBinding */) {
+                return ts.setTextRange(ts.createPropertyAccess(ts.createCall(ts.createFileLevelUniqueName("_super"), 
+                /*typeArguments*/ undefined, [argumentExpression]), "value"), location);
+            }
+            else {
+                return ts.setTextRange(ts.createCall(ts.createFileLevelUniqueName("_super"), 
+                /*typeArguments*/ undefined, [argumentExpression]), location);
+            }
+        }
+    }
+    ts.transformES2017 = transformES2017;
+    var awaiterHelper = {
+        name: "typescript:awaiter",
+        scoped: false,
+        priority: 5,
+        text: "\n            var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {\n                return new (P || (P = Promise))(function (resolve, reject) {\n                    function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }\n                    function rejected(value) { try { step(generator[\"throw\"](value)); } catch (e) { reject(e); } }\n                    function step(result) { result.done ? resolve(result.value) : new P(function (resolve) { resolve(result.value); }).then(fulfilled, rejected); }\n                    step((generator = generator.apply(thisArg, _arguments || [])).next());\n                });\n            };"
+    };
+    function createAwaiterHelper(context, hasLexicalArguments, promiseConstructor, body) {
+        context.requestEmitHelper(awaiterHelper);
+        var generatorFunc = ts.createFunctionExpression(
+        /*modifiers*/ undefined, ts.createToken(39 /* AsteriskToken */), 
+        /*name*/ undefined, 
+        /*typeParameters*/ undefined, 
+        /*parameters*/ [], 
+        /*type*/ undefined, body);
+        // Mark this node as originally an async function
+        (generatorFunc.emitNode || (generatorFunc.emitNode = {})).flags |= 262144 /* AsyncFunctionBody */ | 524288 /* ReuseTempVariableScope */;
+        return ts.createCall(ts.getHelperName("__awaiter"), 
+        /*typeArguments*/ undefined, [
+            ts.createThis(),
+            hasLexicalArguments ? ts.createIdentifier("arguments") : ts.createVoidZero(),
+            promiseConstructor ? ts.createExpressionFromEntityName(promiseConstructor) : ts.createVoidZero(),
+            generatorFunc
+        ]);
+    }
+    ts.asyncSuperHelper = {
+        name: "typescript:async-super",
+        scoped: true,
+        text: ts.helperString(__makeTemplateObject(["\n            const ", " = name => super[name];"], ["\n            const ", " = name => super[name];"]), "_super")
+    };
+    ts.advancedAsyncSuperHelper = {
+        name: "typescript:advanced-async-super",
+        scoped: true,
+        text: ts.helperString(__makeTemplateObject(["\n            const ", " = (function (geti, seti) {\n                const cache = Object.create(null);\n                return name => cache[name] || (cache[name] = { get value() { return geti(name); }, set value(v) { seti(name, v); } });\n            })(name => super[name], (name, value) => super[name] = value);"], ["\n            const ", " = (function (geti, seti) {\n                const cache = Object.create(null);\n                return name => cache[name] || (cache[name] = { get value() { return geti(name); }, set value(v) { seti(name, v); } });\n            })(name => super[name], (name, value) => super[name] = value);"]), "_super")
+    };
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    var ESNextSubstitutionFlags;
+    (function (ESNextSubstitutionFlags) {
+        /** Enables substitutions for async methods with `super` calls. */
+        ESNextSubstitutionFlags[ESNextSubstitutionFlags["AsyncMethodsWithSuper"] = 1] = "AsyncMethodsWithSuper";
+    })(ESNextSubstitutionFlags || (ESNextSubstitutionFlags = {}));
+    function transformESNext(context) {
+        var resumeLexicalEnvironment = context.resumeLexicalEnvironment, endLexicalEnvironment = context.endLexicalEnvironment, hoistVariableDeclaration = context.hoistVariableDeclaration;
+        var resolver = context.getEmitResolver();
+        var compilerOptions = context.getCompilerOptions();
+        var languageVersion = ts.getEmitScriptTarget(compilerOptions);
+        var previousOnEmitNode = context.onEmitNode;
+        context.onEmitNode = onEmitNode;
+        var previousOnSubstituteNode = context.onSubstituteNode;
+        context.onSubstituteNode = onSubstituteNode;
+        var enabledSubstitutions;
+        var enclosingFunctionFlags;
+        var enclosingSuperContainerFlags = 0;
+        return ts.chainBundle(transformSourceFile);
+        function transformSourceFile(node) {
+            if (node.isDeclarationFile) {
+                return node;
+            }
+            var visited = ts.visitEachChild(node, visitor, context);
+            ts.addEmitHelpers(visited, context.readEmitHelpers());
+            return visited;
+        }
+        function visitor(node) {
+            return visitorWorker(node, /*noDestructuringValue*/ false);
+        }
+        function visitorNoDestructuringValue(node) {
+            return visitorWorker(node, /*noDestructuringValue*/ true);
+        }
+        function visitorNoAsyncModifier(node) {
+            if (node.kind === 120 /* AsyncKeyword */) {
+                return undefined;
+            }
+            return node;
+        }
+        function visitorWorker(node, noDestructuringValue) {
+            if ((node.transformFlags & 8 /* ContainsESNext */) === 0) {
+                return node;
+            }
+            switch (node.kind) {
+                case 197 /* AwaitExpression */:
+                    return visitAwaitExpression(node);
+                case 203 /* YieldExpression */:
+                    return visitYieldExpression(node);
+                case 225 /* ReturnStatement */:
+                    return visitReturnStatement(node);
+                case 228 /* LabeledStatement */:
+                    return visitLabeledStatement(node);
+                case 184 /* ObjectLiteralExpression */:
+                    return visitObjectLiteralExpression(node);
+                case 200 /* BinaryExpression */:
+                    return visitBinaryExpression(node, noDestructuringValue);
+                case 232 /* VariableDeclaration */:
+                    return visitVariableDeclaration(node);
+                case 222 /* ForOfStatement */:
+                    return visitForOfStatement(node, /*outermostLabeledStatement*/ undefined);
+                case 220 /* ForStatement */:
+                    return visitForStatement(node);
+                case 196 /* VoidExpression */:
+                    return visitVoidExpression(node);
+                case 155 /* Constructor */:
+                    return visitConstructorDeclaration(node);
+                case 154 /* MethodDeclaration */:
+                    return visitMethodDeclaration(node);
+                case 156 /* GetAccessor */:
+                    return visitGetAccessorDeclaration(node);
+                case 157 /* SetAccessor */:
+                    return visitSetAccessorDeclaration(node);
+                case 234 /* FunctionDeclaration */:
+                    return visitFunctionDeclaration(node);
+                case 192 /* FunctionExpression */:
+                    return visitFunctionExpression(node);
+                case 193 /* ArrowFunction */:
+                    return visitArrowFunction(node);
+                case 149 /* Parameter */:
+                    return visitParameter(node);
+                case 216 /* ExpressionStatement */:
+                    return visitExpressionStatement(node);
+                case 191 /* ParenthesizedExpression */:
+                    return visitParenthesizedExpression(node, noDestructuringValue);
+                case 269 /* CatchClause */:
+                    return visitCatchClause(node);
+                default:
+                    return ts.visitEachChild(node, visitor, context);
+            }
+        }
+        function visitAwaitExpression(node) {
+            if (enclosingFunctionFlags & 2 /* Async */ && enclosingFunctionFlags & 1 /* Generator */) {
+                return ts.setOriginalNode(ts.setTextRange(ts.createYield(createAwaitHelper(context, ts.visitNode(node.expression, visitor, ts.isExpression))), 
+                /*location*/ node), node);
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitYieldExpression(node) {
+            if (enclosingFunctionFlags & 2 /* Async */ && enclosingFunctionFlags & 1 /* Generator */) {
+                if (node.asteriskToken) {
+                    var expression = ts.visitNode(node.expression, visitor, ts.isExpression);
+                    return ts.setOriginalNode(ts.setTextRange(ts.createYield(createAwaitHelper(context, ts.updateYield(node, node.asteriskToken, createAsyncDelegatorHelper(context, createAsyncValuesHelper(context, expression, expression), expression)))), node), node);
+                }
+                return ts.setOriginalNode(ts.setTextRange(ts.createYield(createDownlevelAwait(node.expression
+                    ? ts.visitNode(node.expression, visitor, ts.isExpression)
+                    : ts.createVoidZero())), node), node);
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitReturnStatement(node) {
+            if (enclosingFunctionFlags & 2 /* Async */ && enclosingFunctionFlags & 1 /* Generator */) {
+                return ts.updateReturn(node, createDownlevelAwait(node.expression ? ts.visitNode(node.expression, visitor, ts.isExpression) : ts.createVoidZero()));
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitLabeledStatement(node) {
+            if (enclosingFunctionFlags & 2 /* Async */) {
+                var statement = ts.unwrapInnermostStatementOfLabel(node);
+                if (statement.kind === 222 /* ForOfStatement */ && statement.awaitModifier) {
+                    return visitForOfStatement(statement, node);
+                }
+                return ts.restoreEnclosingLabel(ts.visitEachChild(statement, visitor, context), node);
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function chunkObjectLiteralElements(elements) {
+            var chunkObject;
+            var objects = [];
+            for (var _i = 0, elements_4 = elements; _i < elements_4.length; _i++) {
+                var e = elements_4[_i];
+                if (e.kind === 272 /* SpreadAssignment */) {
+                    if (chunkObject) {
+                        objects.push(ts.createObjectLiteral(chunkObject));
+                        chunkObject = undefined;
+                    }
+                    var target = e.expression;
+                    objects.push(ts.visitNode(target, visitor, ts.isExpression));
+                }
+                else {
+                    chunkObject = ts.append(chunkObject, e.kind === 270 /* PropertyAssignment */
+                        ? ts.createPropertyAssignment(e.name, ts.visitNode(e.initializer, visitor, ts.isExpression))
+                        : ts.visitNode(e, visitor, ts.isObjectLiteralElementLike));
+                }
+            }
+            if (chunkObject) {
+                objects.push(ts.createObjectLiteral(chunkObject));
+            }
+            return objects;
+        }
+        function visitObjectLiteralExpression(node) {
+            if (node.transformFlags & 1048576 /* ContainsObjectSpread */) {
+                // spread elements emit like so:
+                // non-spread elements are chunked together into object literals, and then all are passed to __assign:
+                //     { a, ...o, b } => __assign({a}, o, {b});
+                // If the first element is a spread element, then the first argument to __assign is {}:
+                //     { ...o, a, b, ...o2 } => __assign({}, o, {a, b}, o2)
+                var objects = chunkObjectLiteralElements(node.properties);
+                if (objects.length && objects[0].kind !== 184 /* ObjectLiteralExpression */) {
+                    objects.unshift(ts.createObjectLiteral());
+                }
+                return createAssignHelper(context, objects);
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitExpressionStatement(node) {
+            return ts.visitEachChild(node, visitorNoDestructuringValue, context);
+        }
+        function visitParenthesizedExpression(node, noDestructuringValue) {
+            return ts.visitEachChild(node, noDestructuringValue ? visitorNoDestructuringValue : visitor, context);
+        }
+        function visitCatchClause(node) {
+            if (!node.variableDeclaration) {
+                return ts.updateCatchClause(node, ts.createVariableDeclaration(ts.createTempVariable(/*recordTempVariable*/ undefined)), ts.visitNode(node.block, visitor, ts.isBlock));
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        /**
+         * Visits a BinaryExpression that contains a destructuring assignment.
+         *
+         * @param node A BinaryExpression node.
+         */
+        function visitBinaryExpression(node, noDestructuringValue) {
+            if (ts.isDestructuringAssignment(node) && node.left.transformFlags & 1048576 /* ContainsObjectRest */) {
+                return ts.flattenDestructuringAssignment(node, visitor, context, 1 /* ObjectRest */, !noDestructuringValue);
+            }
+            else if (node.operatorToken.kind === 26 /* CommaToken */) {
+                return ts.updateBinary(node, ts.visitNode(node.left, visitorNoDestructuringValue, ts.isExpression), ts.visitNode(node.right, noDestructuringValue ? visitorNoDestructuringValue : visitor, ts.isExpression));
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        /**
+         * Visits a VariableDeclaration node with a binding pattern.
+         *
+         * @param node A VariableDeclaration node.
+         */
+        function visitVariableDeclaration(node) {
+            // If we are here it is because the name contains a binding pattern with a rest somewhere in it.
+            if (ts.isBindingPattern(node.name) && node.name.transformFlags & 1048576 /* ContainsObjectRest */) {
+                return ts.flattenDestructuringBinding(node, visitor, context, 1 /* ObjectRest */);
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitForStatement(node) {
+            return ts.updateFor(node, ts.visitNode(node.initializer, visitorNoDestructuringValue, ts.isForInitializer), ts.visitNode(node.condition, visitor, ts.isExpression), ts.visitNode(node.incrementor, visitor, ts.isExpression), ts.visitNode(node.statement, visitor, ts.isStatement));
+        }
+        function visitVoidExpression(node) {
+            return ts.visitEachChild(node, visitorNoDestructuringValue, context);
+        }
+        /**
+         * Visits a ForOfStatement and converts it into a ES2015-compatible ForOfStatement.
+         *
+         * @param node A ForOfStatement.
+         */
+        function visitForOfStatement(node, outermostLabeledStatement) {
+            if (node.initializer.transformFlags & 1048576 /* ContainsObjectRest */) {
+                node = transformForOfStatementWithObjectRest(node);
+            }
+            if (node.awaitModifier) {
+                return transformForAwaitOfStatement(node, outermostLabeledStatement);
+            }
+            else {
+                return ts.restoreEnclosingLabel(ts.visitEachChild(node, visitor, context), outermostLabeledStatement);
+            }
+        }
+        function transformForOfStatementWithObjectRest(node) {
+            var initializerWithoutParens = ts.skipParentheses(node.initializer);
+            if (ts.isVariableDeclarationList(initializerWithoutParens) || ts.isAssignmentPattern(initializerWithoutParens)) {
+                var bodyLocation = void 0;
+                var statementsLocation = void 0;
+                var temp = ts.createTempVariable(/*recordTempVariable*/ undefined);
+                var statements = [ts.createForOfBindingStatement(initializerWithoutParens, temp)];
+                if (ts.isBlock(node.statement)) {
+                    ts.addRange(statements, node.statement.statements);
+                    bodyLocation = node.statement;
+                    statementsLocation = node.statement.statements;
+                }
+                else if (node.statement) {
+                    ts.append(statements, node.statement);
+                    bodyLocation = node.statement;
+                    statementsLocation = node.statement;
+                }
+                return ts.updateForOf(node, node.awaitModifier, ts.setTextRange(ts.createVariableDeclarationList([
+                    ts.setTextRange(ts.createVariableDeclaration(temp), node.initializer)
+                ], 1 /* Let */), node.initializer), node.expression, ts.setTextRange(ts.createBlock(ts.setTextRange(ts.createNodeArray(statements), statementsLocation), 
+                /*multiLine*/ true), bodyLocation));
+            }
+            return node;
+        }
+        function convertForOfStatementHead(node, boundValue) {
+            var binding = ts.createForOfBindingStatement(node.initializer, boundValue);
+            var bodyLocation;
+            var statementsLocation;
+            var statements = [ts.visitNode(binding, visitor, ts.isStatement)];
+            var statement = ts.visitNode(node.statement, visitor, ts.isStatement);
+            if (ts.isBlock(statement)) {
+                ts.addRange(statements, statement.statements);
+                bodyLocation = statement;
+                statementsLocation = statement.statements;
+            }
+            else {
+                statements.push(statement);
+            }
+            return ts.setEmitFlags(ts.setTextRange(ts.createBlock(ts.setTextRange(ts.createNodeArray(statements), statementsLocation), 
+            /*multiLine*/ true), bodyLocation), 48 /* NoSourceMap */ | 384 /* NoTokenSourceMaps */);
+        }
+        function createDownlevelAwait(expression) {
+            return enclosingFunctionFlags & 1 /* Generator */
+                ? ts.createYield(/*asteriskToken*/ undefined, createAwaitHelper(context, expression))
+                : ts.createAwait(expression);
+        }
+        function transformForAwaitOfStatement(node, outermostLabeledStatement) {
+            var expression = ts.visitNode(node.expression, visitor, ts.isExpression);
+            var iterator = ts.isIdentifier(expression) ? ts.getGeneratedNameForNode(expression) : ts.createTempVariable(/*recordTempVariable*/ undefined);
+            var result = ts.isIdentifier(expression) ? ts.getGeneratedNameForNode(iterator) : ts.createTempVariable(/*recordTempVariable*/ undefined);
+            var errorRecord = ts.createUniqueName("e");
+            var catchVariable = ts.getGeneratedNameForNode(errorRecord);
+            var returnMethod = ts.createTempVariable(/*recordTempVariable*/ undefined);
+            var callValues = createAsyncValuesHelper(context, expression, /*location*/ node.expression);
+            var callNext = ts.createCall(ts.createPropertyAccess(iterator, "next"), /*typeArguments*/ undefined, []);
+            var getDone = ts.createPropertyAccess(result, "done");
+            var getValue = ts.createPropertyAccess(result, "value");
+            var callReturn = ts.createFunctionCall(returnMethod, iterator, []);
+            hoistVariableDeclaration(errorRecord);
+            hoistVariableDeclaration(returnMethod);
+            var forStatement = ts.setEmitFlags(ts.setTextRange(ts.createFor(
+            /*initializer*/ ts.setEmitFlags(ts.setTextRange(ts.createVariableDeclarationList([
+                ts.setTextRange(ts.createVariableDeclaration(iterator, /*type*/ undefined, callValues), node.expression),
+                ts.createVariableDeclaration(result)
+            ]), node.expression), 2097152 /* NoHoisting */), 
+            /*condition*/ ts.createComma(ts.createAssignment(result, createDownlevelAwait(callNext)), ts.createLogicalNot(getDone)), 
+            /*incrementor*/ undefined, 
+            /*statement*/ convertForOfStatementHead(node, getValue)), 
+            /*location*/ node), 256 /* NoTokenTrailingSourceMaps */);
+            return ts.createTry(ts.createBlock([
+                ts.restoreEnclosingLabel(forStatement, outermostLabeledStatement)
+            ]), ts.createCatchClause(ts.createVariableDeclaration(catchVariable), ts.setEmitFlags(ts.createBlock([
+                ts.createStatement(ts.createAssignment(errorRecord, ts.createObjectLiteral([
+                    ts.createPropertyAssignment("error", catchVariable)
+                ])))
+            ]), 1 /* SingleLine */)), ts.createBlock([
+                ts.createTry(
+                /*tryBlock*/ ts.createBlock([
+                    ts.setEmitFlags(ts.createIf(ts.createLogicalAnd(ts.createLogicalAnd(result, ts.createLogicalNot(getDone)), ts.createAssignment(returnMethod, ts.createPropertyAccess(iterator, "return"))), ts.createStatement(createDownlevelAwait(callReturn))), 1 /* SingleLine */)
+                ]), 
+                /*catchClause*/ undefined, 
+                /*finallyBlock*/ ts.setEmitFlags(ts.createBlock([
+                    ts.setEmitFlags(ts.createIf(errorRecord, ts.createThrow(ts.createPropertyAccess(errorRecord, "error"))), 1 /* SingleLine */)
+                ]), 1 /* SingleLine */))
+            ]));
+        }
+        function visitParameter(node) {
+            if (node.transformFlags & 1048576 /* ContainsObjectRest */) {
+                // Binding patterns are converted into a generated name and are
+                // evaluated inside the function body.
+                return ts.updateParameter(node, 
+                /*decorators*/ undefined, 
+                /*modifiers*/ undefined, node.dotDotDotToken, ts.getGeneratedNameForNode(node), 
+                /*questionToken*/ undefined, 
+                /*type*/ undefined, ts.visitNode(node.initializer, visitor, ts.isExpression));
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitConstructorDeclaration(node) {
+            var savedEnclosingFunctionFlags = enclosingFunctionFlags;
+            enclosingFunctionFlags = 0 /* Normal */;
+            var updated = ts.updateConstructor(node, 
+            /*decorators*/ undefined, node.modifiers, ts.visitParameterList(node.parameters, visitor, context), transformFunctionBody(node));
+            enclosingFunctionFlags = savedEnclosingFunctionFlags;
+            return updated;
+        }
+        function visitGetAccessorDeclaration(node) {
+            var savedEnclosingFunctionFlags = enclosingFunctionFlags;
+            enclosingFunctionFlags = 0 /* Normal */;
+            var updated = ts.updateGetAccessor(node, 
+            /*decorators*/ undefined, node.modifiers, ts.visitNode(node.name, visitor, ts.isPropertyName), ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, transformFunctionBody(node));
+            enclosingFunctionFlags = savedEnclosingFunctionFlags;
+            return updated;
+        }
+        function visitSetAccessorDeclaration(node) {
+            var savedEnclosingFunctionFlags = enclosingFunctionFlags;
+            enclosingFunctionFlags = 0 /* Normal */;
+            var updated = ts.updateSetAccessor(node, 
+            /*decorators*/ undefined, node.modifiers, ts.visitNode(node.name, visitor, ts.isPropertyName), ts.visitParameterList(node.parameters, visitor, context), transformFunctionBody(node));
+            enclosingFunctionFlags = savedEnclosingFunctionFlags;
+            return updated;
+        }
+        function visitMethodDeclaration(node) {
+            var savedEnclosingFunctionFlags = enclosingFunctionFlags;
+            enclosingFunctionFlags = ts.getFunctionFlags(node);
+            var updated = ts.updateMethod(node, 
+            /*decorators*/ undefined, enclosingFunctionFlags & 1 /* Generator */
+                ? ts.visitNodes(node.modifiers, visitorNoAsyncModifier, ts.isModifier)
+                : node.modifiers, enclosingFunctionFlags & 2 /* Async */
+                ? undefined
+                : node.asteriskToken, ts.visitNode(node.name, visitor, ts.isPropertyName), ts.visitNode(/*questionToken*/ undefined, visitor, ts.isToken), 
+            /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, enclosingFunctionFlags & 2 /* Async */ && enclosingFunctionFlags & 1 /* Generator */
+                ? transformAsyncGeneratorFunctionBody(node)
+                : transformFunctionBody(node));
+            enclosingFunctionFlags = savedEnclosingFunctionFlags;
+            return updated;
+        }
+        function visitFunctionDeclaration(node) {
+            var savedEnclosingFunctionFlags = enclosingFunctionFlags;
+            enclosingFunctionFlags = ts.getFunctionFlags(node);
+            var updated = ts.updateFunctionDeclaration(node, 
+            /*decorators*/ undefined, enclosingFunctionFlags & 1 /* Generator */
+                ? ts.visitNodes(node.modifiers, visitorNoAsyncModifier, ts.isModifier)
+                : node.modifiers, enclosingFunctionFlags & 2 /* Async */
+                ? undefined
+                : node.asteriskToken, node.name, 
+            /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, enclosingFunctionFlags & 2 /* Async */ && enclosingFunctionFlags & 1 /* Generator */
+                ? transformAsyncGeneratorFunctionBody(node)
+                : transformFunctionBody(node));
+            enclosingFunctionFlags = savedEnclosingFunctionFlags;
+            return updated;
+        }
+        function visitArrowFunction(node) {
+            var savedEnclosingFunctionFlags = enclosingFunctionFlags;
+            enclosingFunctionFlags = ts.getFunctionFlags(node);
+            var updated = ts.updateArrowFunction(node, node.modifiers, 
+            /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, node.equalsGreaterThanToken, transformFunctionBody(node));
+            enclosingFunctionFlags = savedEnclosingFunctionFlags;
+            return updated;
+        }
+        function visitFunctionExpression(node) {
+            var savedEnclosingFunctionFlags = enclosingFunctionFlags;
+            enclosingFunctionFlags = ts.getFunctionFlags(node);
+            var updated = ts.updateFunctionExpression(node, enclosingFunctionFlags & 1 /* Generator */
+                ? ts.visitNodes(node.modifiers, visitorNoAsyncModifier, ts.isModifier)
+                : node.modifiers, enclosingFunctionFlags & 2 /* Async */
+                ? undefined
+                : node.asteriskToken, node.name, 
+            /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, enclosingFunctionFlags & 2 /* Async */ && enclosingFunctionFlags & 1 /* Generator */
+                ? transformAsyncGeneratorFunctionBody(node)
+                : transformFunctionBody(node));
+            enclosingFunctionFlags = savedEnclosingFunctionFlags;
+            return updated;
+        }
+        function transformAsyncGeneratorFunctionBody(node) {
+            resumeLexicalEnvironment();
+            var statements = [];
+            var statementOffset = ts.addPrologue(statements, node.body.statements, /*ensureUseStrict*/ false, visitor);
+            appendObjectRestAssignmentsIfNeeded(statements, node);
+            statements.push(ts.createReturn(createAsyncGeneratorHelper(context, ts.createFunctionExpression(
+            /*modifiers*/ undefined, ts.createToken(39 /* AsteriskToken */), node.name && ts.getGeneratedNameForNode(node.name), 
+            /*typeParameters*/ undefined, 
+            /*parameters*/ [], 
+            /*type*/ undefined, ts.updateBlock(node.body, ts.visitLexicalEnvironment(node.body.statements, visitor, context, statementOffset))))));
+            ts.prependStatements(statements, endLexicalEnvironment());
+            var block = ts.updateBlock(node.body, statements);
+            // Minor optimization, emit `_super` helper to capture `super` access in an arrow.
+            // This step isn't needed if we eventually transform this to ES5.
+            if (languageVersion >= 2 /* ES2015 */) {
+                if (resolver.getNodeCheckFlags(node) & 4096 /* AsyncMethodWithSuperBinding */) {
+                    enableSubstitutionForAsyncMethodsWithSuper();
+                    ts.addEmitHelper(block, ts.advancedAsyncSuperHelper);
+                }
+                else if (resolver.getNodeCheckFlags(node) & 2048 /* AsyncMethodWithSuper */) {
+                    enableSubstitutionForAsyncMethodsWithSuper();
+                    ts.addEmitHelper(block, ts.asyncSuperHelper);
+                }
+            }
+            return block;
+        }
+        function transformFunctionBody(node) {
+            resumeLexicalEnvironment();
+            var statementOffset = 0;
+            var statements = [];
+            var body = ts.visitNode(node.body, visitor, ts.isConciseBody);
+            if (ts.isBlock(body)) {
+                statementOffset = ts.addPrologue(statements, body.statements, /*ensureUseStrict*/ false, visitor);
+            }
+            ts.addRange(statements, appendObjectRestAssignmentsIfNeeded(/*statements*/ undefined, node));
+            var leadingStatements = endLexicalEnvironment();
+            if (statementOffset > 0 || ts.some(statements) || ts.some(leadingStatements)) {
+                var block = ts.convertToFunctionBody(body, /*multiLine*/ true);
+                ts.prependStatements(statements, leadingStatements);
+                ts.addRange(statements, block.statements.slice(statementOffset));
+                return ts.updateBlock(block, ts.setTextRange(ts.createNodeArray(statements), block.statements));
+            }
+            return body;
+        }
+        function appendObjectRestAssignmentsIfNeeded(statements, node) {
+            for (var _i = 0, _a = node.parameters; _i < _a.length; _i++) {
+                var parameter = _a[_i];
+                if (parameter.transformFlags & 1048576 /* ContainsObjectRest */) {
+                    var temp = ts.getGeneratedNameForNode(parameter);
+                    var declarations = ts.flattenDestructuringBinding(parameter, visitor, context, 1 /* ObjectRest */, temp, 
+                    /*doNotRecordTempVariablesInLine*/ false, 
+                    /*skipInitializer*/ true);
+                    if (ts.some(declarations)) {
+                        var statement = ts.createVariableStatement(
+                        /*modifiers*/ undefined, ts.createVariableDeclarationList(declarations));
+                        ts.setEmitFlags(statement, 1048576 /* CustomPrologue */);
+                        statements = ts.append(statements, statement);
+                    }
+                }
+            }
+            return statements;
+        }
+        function enableSubstitutionForAsyncMethodsWithSuper() {
+            if ((enabledSubstitutions & 1 /* AsyncMethodsWithSuper */) === 0) {
+                enabledSubstitutions |= 1 /* AsyncMethodsWithSuper */;
+                // We need to enable substitutions for call, property access, and element access
+                // if we need to rewrite super calls.
+                context.enableSubstitution(187 /* CallExpression */);
+                context.enableSubstitution(185 /* PropertyAccessExpression */);
+                context.enableSubstitution(186 /* ElementAccessExpression */);
+                // We need to be notified when entering and exiting declarations that bind super.
+                context.enableEmitNotification(235 /* ClassDeclaration */);
+                context.enableEmitNotification(154 /* MethodDeclaration */);
+                context.enableEmitNotification(156 /* GetAccessor */);
+                context.enableEmitNotification(157 /* SetAccessor */);
+                context.enableEmitNotification(155 /* Constructor */);
+            }
+        }
+        /**
+         * Called by the printer just before a node is printed.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to be printed.
+         * @param emitCallback The callback used to emit the node.
+         */
+        function onEmitNode(hint, node, emitCallback) {
+            // If we need to support substitutions for `super` in an async method,
+            // we should track it here.
+            if (enabledSubstitutions & 1 /* AsyncMethodsWithSuper */ && isSuperContainer(node)) {
+                var superContainerFlags = resolver.getNodeCheckFlags(node) & (2048 /* AsyncMethodWithSuper */ | 4096 /* AsyncMethodWithSuperBinding */);
+                if (superContainerFlags !== enclosingSuperContainerFlags) {
+                    var savedEnclosingSuperContainerFlags = enclosingSuperContainerFlags;
+                    enclosingSuperContainerFlags = superContainerFlags;
+                    previousOnEmitNode(hint, node, emitCallback);
+                    enclosingSuperContainerFlags = savedEnclosingSuperContainerFlags;
+                    return;
+                }
+            }
+            previousOnEmitNode(hint, node, emitCallback);
+        }
+        /**
+         * Hooks node substitutions.
+         *
+         * @param hint The context for the emitter.
+         * @param node The node to substitute.
+         */
+        function onSubstituteNode(hint, node) {
+            node = previousOnSubstituteNode(hint, node);
+            if (hint === 1 /* Expression */ && enclosingSuperContainerFlags) {
+                return substituteExpression(node);
+            }
+            return node;
+        }
+        function substituteExpression(node) {
+            switch (node.kind) {
+                case 185 /* PropertyAccessExpression */:
+                    return substitutePropertyAccessExpression(node);
+                case 186 /* ElementAccessExpression */:
+                    return substituteElementAccessExpression(node);
+                case 187 /* CallExpression */:
+                    return substituteCallExpression(node);
+            }
+            return node;
+        }
+        function substitutePropertyAccessExpression(node) {
+            if (node.expression.kind === 97 /* SuperKeyword */) {
+                return createSuperAccessInAsyncMethod(ts.createLiteral(ts.idText(node.name)), node);
+            }
+            return node;
+        }
+        function substituteElementAccessExpression(node) {
+            if (node.expression.kind === 97 /* SuperKeyword */) {
+                return createSuperAccessInAsyncMethod(node.argumentExpression, node);
+            }
+            return node;
+        }
+        function substituteCallExpression(node) {
+            var expression = node.expression;
+            if (ts.isSuperProperty(expression)) {
+                var argumentExpression = ts.isPropertyAccessExpression(expression)
+                    ? substitutePropertyAccessExpression(expression)
+                    : substituteElementAccessExpression(expression);
+                return ts.createCall(ts.createPropertyAccess(argumentExpression, "call"), 
+                /*typeArguments*/ undefined, [
+                    ts.createThis()
+                ].concat(node.arguments));
+            }
+            return node;
+        }
+        function isSuperContainer(node) {
+            var kind = node.kind;
+            return kind === 235 /* ClassDeclaration */
+                || kind === 155 /* Constructor */
+                || kind === 154 /* MethodDeclaration */
+                || kind === 156 /* GetAccessor */
+                || kind === 157 /* SetAccessor */;
+        }
+        function createSuperAccessInAsyncMethod(argumentExpression, location) {
+            if (enclosingSuperContainerFlags & 4096 /* AsyncMethodWithSuperBinding */) {
+                return ts.setTextRange(ts.createPropertyAccess(ts.createCall(ts.createIdentifier("_super"), 
+                /*typeArguments*/ undefined, [argumentExpression]), "value"), location);
+            }
+            else {
+                return ts.setTextRange(ts.createCall(ts.createIdentifier("_super"), 
+                /*typeArguments*/ undefined, [argumentExpression]), location);
+            }
+        }
+    }
+    ts.transformESNext = transformESNext;
+    var assignHelper = {
+        name: "typescript:assign",
+        scoped: false,
+        priority: 1,
+        text: "\n            var __assign = (this && this.__assign) || Object.assign || function(t) {\n                for (var s, i = 1, n = arguments.length; i < n; i++) {\n                    s = arguments[i];\n                    for (var p in s) if (Object.prototype.hasOwnProperty.call(s, p))\n                        t[p] = s[p];\n                }\n                return t;\n            };"
+    };
+    function createAssignHelper(context, attributesSegments) {
+        if (context.getCompilerOptions().target >= 2 /* ES2015 */) {
+            return ts.createCall(ts.createPropertyAccess(ts.createIdentifier("Object"), "assign"), 
+            /*typeArguments*/ undefined, attributesSegments);
+        }
+        context.requestEmitHelper(assignHelper);
+        return ts.createCall(ts.getHelperName("__assign"), 
+        /*typeArguments*/ undefined, attributesSegments);
+    }
+    ts.createAssignHelper = createAssignHelper;
+    var awaitHelper = {
+        name: "typescript:await",
+        scoped: false,
+        text: "\n            var __await = (this && this.__await) || function (v) { return this instanceof __await ? (this.v = v, this) : new __await(v); }"
+    };
+    function createAwaitHelper(context, expression) {
+        context.requestEmitHelper(awaitHelper);
+        return ts.createCall(ts.getHelperName("__await"), /*typeArguments*/ undefined, [expression]);
+    }
+    var asyncGeneratorHelper = {
+        name: "typescript:asyncGenerator",
+        scoped: false,
+        text: "\n            var __asyncGenerator = (this && this.__asyncGenerator) || function (thisArg, _arguments, generator) {\n                if (!Symbol.asyncIterator) throw new TypeError(\"Symbol.asyncIterator is not defined.\");\n                var g = generator.apply(thisArg, _arguments || []), i, q = [];\n                return i = {}, verb(\"next\"), verb(\"throw\"), verb(\"return\"), i[Symbol.asyncIterator] = function () { return this; }, i;\n                function verb(n) { if (g[n]) i[n] = function (v) { return new Promise(function (a, b) { q.push([n, v, a, b]) > 1 || resume(n, v); }); }; }\n                function resume(n, v) { try { step(g[n](v)); } catch (e) { settle(q[0][3], e); } }\n                function step(r) { r.value instanceof __await ? Promise.resolve(r.value.v).then(fulfill, reject) : settle(q[0][2], r); }\n                function fulfill(value) { resume(\"next\", value); }\n                function reject(value) { resume(\"throw\", value); }\n                function settle(f, v) { if (f(v), q.shift(), q.length) resume(q[0][0], q[0][1]); }\n            };"
+    };
+    function createAsyncGeneratorHelper(context, generatorFunc) {
+        context.requestEmitHelper(awaitHelper);
+        context.requestEmitHelper(asyncGeneratorHelper);
+        // Mark this node as originally an async function
+        (generatorFunc.emitNode || (generatorFunc.emitNode = {})).flags |= 262144 /* AsyncFunctionBody */;
+        return ts.createCall(ts.getHelperName("__asyncGenerator"), 
+        /*typeArguments*/ undefined, [
+            ts.createThis(),
+            ts.createIdentifier("arguments"),
+            generatorFunc
+        ]);
+    }
+    var asyncDelegator = {
+        name: "typescript:asyncDelegator",
+        scoped: false,
+        text: "\n            var __asyncDelegator = (this && this.__asyncDelegator) || function (o) {\n                var i, p;\n                return i = {}, verb(\"next\"), verb(\"throw\", function (e) { throw e; }), verb(\"return\"), i[Symbol.iterator] = function () { return this; }, i;\n                function verb(n, f) { i[n] = o[n] ? function (v) { return (p = !p) ? { value: __await(o[n](v)), done: n === \"return\" } : f ? f(v) : v; } : f; }\n            };"
+    };
+    function createAsyncDelegatorHelper(context, expression, location) {
+        context.requestEmitHelper(awaitHelper);
+        context.requestEmitHelper(asyncDelegator);
+        return ts.setTextRange(ts.createCall(ts.getHelperName("__asyncDelegator"), 
+        /*typeArguments*/ undefined, [expression]), location);
+    }
+    var asyncValues = {
+        name: "typescript:asyncValues",
+        scoped: false,
+        text: "\n            var __asyncValues = (this && this.__asyncValues) || function (o) {\n                if (!Symbol.asyncIterator) throw new TypeError(\"Symbol.asyncIterator is not defined.\");\n                var m = o[Symbol.asyncIterator], i;\n                return m ? m.call(o) : (o = typeof __values === \"function\" ? __values(o) : o[Symbol.iterator](), i = {}, verb(\"next\"), verb(\"throw\"), verb(\"return\"), i[Symbol.asyncIterator] = function () { return this; }, i);\n                function verb(n) { i[n] = o[n] && function (v) { return new Promise(function (resolve, reject) { v = o[n](v), settle(resolve, reject, v.done, v.value); }); }; }\n                function settle(resolve, reject, d, v) { Promise.resolve(v).then(function(v) { resolve({ value: v, done: d }); }, reject); }\n            };"
+    };
+    function createAsyncValuesHelper(context, expression, location) {
+        context.requestEmitHelper(asyncValues);
+        return ts.setTextRange(ts.createCall(ts.getHelperName("__asyncValues"), 
+        /*typeArguments*/ undefined, [expression]), location);
+    }
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    function transformJsx(context) {
+        var compilerOptions = context.getCompilerOptions();
+        var currentSourceFile;
+        return ts.chainBundle(transformSourceFile);
+        /**
+         * Transform JSX-specific syntax in a SourceFile.
+         *
+         * @param node A SourceFile node.
+         */
+        function transformSourceFile(node) {
+            if (node.isDeclarationFile) {
+                return node;
+            }
+            currentSourceFile = node;
+            var visited = ts.visitEachChild(node, visitor, context);
+            ts.addEmitHelpers(visited, context.readEmitHelpers());
+            return visited;
+        }
+        function visitor(node) {
+            if (node.transformFlags & 4 /* ContainsJsx */) {
+                return visitorWorker(node);
+            }
+            else {
+                return node;
+            }
+        }
+        function visitorWorker(node) {
+            switch (node.kind) {
+                case 255 /* JsxElement */:
+                    return visitJsxElement(node, /*isChild*/ false);
+                case 256 /* JsxSelfClosingElement */:
+                    return visitJsxSelfClosingElement(node, /*isChild*/ false);
+                case 259 /* JsxFragment */:
+                    return visitJsxFragment(node, /*isChild*/ false);
+                case 265 /* JsxExpression */:
+                    return visitJsxExpression(node);
+                default:
+                    return ts.visitEachChild(node, visitor, context);
+            }
+        }
+        function transformJsxChildToExpression(node) {
+            switch (node.kind) {
+                case 10 /* JsxText */:
+                    return visitJsxText(node);
+                case 265 /* JsxExpression */:
+                    return visitJsxExpression(node);
+                case 255 /* JsxElement */:
+                    return visitJsxElement(node, /*isChild*/ true);
+                case 256 /* JsxSelfClosingElement */:
+                    return visitJsxSelfClosingElement(node, /*isChild*/ true);
+                case 259 /* JsxFragment */:
+                    return visitJsxFragment(node, /*isChild*/ true);
+                default:
+                    return ts.Debug.failBadSyntaxKind(node);
+            }
+        }
+        function visitJsxElement(node, isChild) {
+            return visitJsxOpeningLikeElement(node.openingElement, node.children, isChild, /*location*/ node);
+        }
+        function visitJsxSelfClosingElement(node, isChild) {
+            return visitJsxOpeningLikeElement(node, /*children*/ undefined, isChild, /*location*/ node);
+        }
+        function visitJsxFragment(node, isChild) {
+            return visitJsxOpeningFragment(node.openingFragment, node.children, isChild, /*location*/ node);
+        }
+        function visitJsxOpeningLikeElement(node, children, isChild, location) {
+            var tagName = getTagName(node);
+            var objectProperties;
+            var attrs = node.attributes.properties;
+            if (attrs.length === 0) {
+                // When there are no attributes, React wants "null"
+                objectProperties = ts.createNull();
+            }
+            else {
+                // Map spans of JsxAttribute nodes into object literals and spans
+                // of JsxSpreadAttribute nodes into expressions.
+                var segments = ts.flatten(ts.spanMap(attrs, ts.isJsxSpreadAttribute, function (attrs, isSpread) { return isSpread
+                    ? ts.map(attrs, transformJsxSpreadAttributeToExpression)
+                    : ts.createObjectLiteral(ts.map(attrs, transformJsxAttributeToObjectLiteralElement)); }));
+                if (ts.isJsxSpreadAttribute(attrs[0])) {
+                    // We must always emit at least one object literal before a spread
+                    // argument.
+                    segments.unshift(ts.createObjectLiteral());
+                }
+                // Either emit one big object literal (no spread attribs), or
+                // a call to the __assign helper.
+                objectProperties = ts.singleOrUndefined(segments);
+                if (!objectProperties) {
+                    objectProperties = ts.createAssignHelper(context, segments);
+                }
+            }
+            var element = ts.createExpressionForJsxElement(context.getEmitResolver().getJsxFactoryEntity(currentSourceFile), compilerOptions.reactNamespace, // TODO: GH#18217
+            tagName, objectProperties, ts.mapDefined(children, transformJsxChildToExpression), node, location);
+            if (isChild) {
+                ts.startOnNewLine(element);
+            }
+            return element;
+        }
+        function visitJsxOpeningFragment(node, children, isChild, location) {
+            var element = ts.createExpressionForJsxFragment(context.getEmitResolver().getJsxFactoryEntity(currentSourceFile), compilerOptions.reactNamespace, // TODO: GH#18217
+            ts.mapDefined(children, transformJsxChildToExpression), node, location);
+            if (isChild) {
+                ts.startOnNewLine(element);
+            }
+            return element;
+        }
+        function transformJsxSpreadAttributeToExpression(node) {
+            return ts.visitNode(node.expression, visitor, ts.isExpression);
+        }
+        function transformJsxAttributeToObjectLiteralElement(node) {
+            var name = getAttributeName(node);
+            var expression = transformJsxAttributeInitializer(node.initializer);
+            return ts.createPropertyAssignment(name, expression);
+        }
+        function transformJsxAttributeInitializer(node) {
+            if (node === undefined) {
+                return ts.createTrue();
+            }
+            else if (node.kind === 9 /* StringLiteral */) {
+                // Always recreate the literal to escape any escape sequences or newlines which may be in the original jsx string and which
+                // Need to be escaped to be handled correctly in a normal string
+                var literal = ts.createLiteral(tryDecodeEntities(node.text) || node.text);
+                literal.singleQuote = node.singleQuote !== undefined ? node.singleQuote : !ts.isStringDoubleQuoted(node, currentSourceFile);
+                return ts.setTextRange(literal, node);
+            }
+            else if (node.kind === 265 /* JsxExpression */) {
+                if (node.expression === undefined) {
+                    return ts.createTrue();
+                }
+                return visitJsxExpression(node);
+            }
+            else {
+                return ts.Debug.failBadSyntaxKind(node);
+            }
+        }
+        function visitJsxText(node) {
+            var fixed = fixupWhitespaceAndDecodeEntities(ts.getTextOfNode(node, /*includeTrivia*/ true));
+            return fixed === undefined ? undefined : ts.createLiteral(fixed);
+        }
+        /**
+         * JSX trims whitespace at the end and beginning of lines, except that the
+         * start/end of a tag is considered a start/end of a line only if that line is
+         * on the same line as the closing tag. See examples in
+         * tests/cases/conformance/jsx/tsxReactEmitWhitespace.tsx
+         * See also https://www.w3.org/TR/html4/struct/text.html#h-9.1 and https://www.w3.org/TR/CSS2/text.html#white-space-model
+         *
+         * An equivalent algorithm would be:
+         * - If there is only one line, return it.
+         * - If there is only whitespace (but multiple lines), return `undefined`.
+         * - Split the text into lines.
+         * - 'trimRight' the first line, 'trimLeft' the last line, 'trim' middle lines.
+         * - Decode entities on each line (individually).
+         * - Remove empty lines and join the rest with " ".
+         */
+        function fixupWhitespaceAndDecodeEntities(text) {
+            var acc;
+            // First non-whitespace character on this line.
+            var firstNonWhitespace = 0;
+            // Last non-whitespace character on this line.
+            var lastNonWhitespace = -1;
+            // These initial values are special because the first line is:
+            // firstNonWhitespace = 0 to indicate that we want leading whitsepace,
+            // but lastNonWhitespace = -1 as a special flag to indicate that we *don't* include the line if it's all whitespace.
+            for (var i = 0; i < text.length; i++) {
+                var c = text.charCodeAt(i);
+                if (ts.isLineBreak(c)) {
+                    // If we've seen any non-whitespace characters on this line, add the 'trim' of the line.
+                    // (lastNonWhitespace === -1 is a special flag to detect whether the first line is all whitespace.)
+                    if (firstNonWhitespace !== -1 && lastNonWhitespace !== -1) {
+                        acc = addLineOfJsxText(acc, text.substr(firstNonWhitespace, lastNonWhitespace - firstNonWhitespace + 1));
+                    }
+                    // Reset firstNonWhitespace for the next line.
+                    // Don't bother to reset lastNonWhitespace because we ignore it if firstNonWhitespace = -1.
+                    firstNonWhitespace = -1;
+                }
+                else if (!ts.isWhiteSpaceSingleLine(c)) {
+                    lastNonWhitespace = i;
+                    if (firstNonWhitespace === -1) {
+                        firstNonWhitespace = i;
+                    }
+                }
+            }
+            return firstNonWhitespace !== -1
+                // Last line had a non-whitespace character. Emit the 'trimLeft', meaning keep trailing whitespace.
+                ? addLineOfJsxText(acc, text.substr(firstNonWhitespace))
+                // Last line was all whitespace, so ignore it
+                : acc;
+        }
+        function addLineOfJsxText(acc, trimmedLine) {
+            // We do not escape the string here as that is handled by the printer
+            // when it emits the literal. We do, however, need to decode JSX entities.
+            var decoded = decodeEntities(trimmedLine);
+            return acc === undefined ? decoded : acc + " " + decoded;
+        }
+        /**
+         * Replace entities like "&nbsp;", "&#123;", and "&#xDEADBEEF;" with the characters they encode.
+         * See https://en.wikipedia.org/wiki/List_of_XML_and_HTML_character_entity_references
+         */
+        function decodeEntities(text) {
+            return text.replace(/&((#((\d+)|x([\da-fA-F]+)))|(\w+));/g, function (match, _all, _number, _digits, decimal, hex, word) {
+                if (decimal) {
+                    return String.fromCharCode(parseInt(decimal, 10));
+                }
+                else if (hex) {
+                    return String.fromCharCode(parseInt(hex, 16));
+                }
+                else {
+                    var ch = entities.get(word);
+                    // If this is not a valid entity, then just use `match` (replace it with itself, i.e. don't replace)
+                    return ch ? String.fromCharCode(ch) : match;
+                }
+            });
+        }
+        /** Like `decodeEntities` but returns `undefined` if there were no entities to decode. */
+        function tryDecodeEntities(text) {
+            var decoded = decodeEntities(text);
+            return decoded === text ? undefined : decoded;
+        }
+        function getTagName(node) {
+            if (node.kind === 255 /* JsxElement */) {
+                return getTagName(node.openingElement);
+            }
+            else {
+                var name = node.tagName;
+                if (ts.isIdentifier(name) && ts.isIntrinsicJsxName(name.escapedText)) {
+                    return ts.createLiteral(ts.idText(name));
+                }
+                else {
+                    return ts.createExpressionFromEntityName(name);
+                }
+            }
+        }
+        /**
+         * Emit an attribute name, which is quoted if it needs to be quoted. Because
+         * these emit into an object literal property name, we don't need to be worried
+         * about keywords, just non-identifier characters
+         */
+        function getAttributeName(node) {
+            var name = node.name;
+            var text = ts.idText(name);
+            if (/^[A-Za-z_]\w*$/.test(text)) {
+                return name;
+            }
+            else {
+                return ts.createLiteral(text);
+            }
+        }
+        function visitJsxExpression(node) {
+            return ts.visitNode(node.expression, visitor, ts.isExpression);
+        }
+    }
+    ts.transformJsx = transformJsx;
+    var entities = ts.createMapFromTemplate({
+        quot: 0x0022,
+        amp: 0x0026,
+        apos: 0x0027,
+        lt: 0x003C,
+        gt: 0x003E,
+        nbsp: 0x00A0,
+        iexcl: 0x00A1,
+        cent: 0x00A2,
+        pound: 0x00A3,
+        curren: 0x00A4,
+        yen: 0x00A5,
+        brvbar: 0x00A6,
+        sect: 0x00A7,
+        uml: 0x00A8,
+        copy: 0x00A9,
+        ordf: 0x00AA,
+        laquo: 0x00AB,
+        not: 0x00AC,
+        shy: 0x00AD,
+        reg: 0x00AE,
+        macr: 0x00AF,
+        deg: 0x00B0,
+        plusmn: 0x00B1,
+        sup2: 0x00B2,
+        sup3: 0x00B3,
+        acute: 0x00B4,
+        micro: 0x00B5,
+        para: 0x00B6,
+        middot: 0x00B7,
+        cedil: 0x00B8,
+        sup1: 0x00B9,
+        ordm: 0x00BA,
+        raquo: 0x00BB,
+        frac14: 0x00BC,
+        frac12: 0x00BD,
+        frac34: 0x00BE,
+        iquest: 0x00BF,
+        Agrave: 0x00C0,
+        Aacute: 0x00C1,
+        Acirc: 0x00C2,
+        Atilde: 0x00C3,
+        Auml: 0x00C4,
+        Aring: 0x00C5,
+        AElig: 0x00C6,
+        Ccedil: 0x00C7,
+        Egrave: 0x00C8,
+        Eacute: 0x00C9,
+        Ecirc: 0x00CA,
+        Euml: 0x00CB,
+        Igrave: 0x00CC,
+        Iacute: 0x00CD,
+        Icirc: 0x00CE,
+        Iuml: 0x00CF,
+        ETH: 0x00D0,
+        Ntilde: 0x00D1,
+        Ograve: 0x00D2,
+        Oacute: 0x00D3,
+        Ocirc: 0x00D4,
+        Otilde: 0x00D5,
+        Ouml: 0x00D6,
+        times: 0x00D7,
+        Oslash: 0x00D8,
+        Ugrave: 0x00D9,
+        Uacute: 0x00DA,
+        Ucirc: 0x00DB,
+        Uuml: 0x00DC,
+        Yacute: 0x00DD,
+        THORN: 0x00DE,
+        szlig: 0x00DF,
+        agrave: 0x00E0,
+        aacute: 0x00E1,
+        acirc: 0x00E2,
+        atilde: 0x00E3,
+        auml: 0x00E4,
+        aring: 0x00E5,
+        aelig: 0x00E6,
+        ccedil: 0x00E7,
+        egrave: 0x00E8,
+        eacute: 0x00E9,
+        ecirc: 0x00EA,
+        euml: 0x00EB,
+        igrave: 0x00EC,
+        iacute: 0x00ED,
+        icirc: 0x00EE,
+        iuml: 0x00EF,
+        eth: 0x00F0,
+        ntilde: 0x00F1,
+        ograve: 0x00F2,
+        oacute: 0x00F3,
+        ocirc: 0x00F4,
+        otilde: 0x00F5,
+        ouml: 0x00F6,
+        divide: 0x00F7,
+        oslash: 0x00F8,
+        ugrave: 0x00F9,
+        uacute: 0x00FA,
+        ucirc: 0x00FB,
+        uuml: 0x00FC,
+        yacute: 0x00FD,
+        thorn: 0x00FE,
+        yuml: 0x00FF,
+        OElig: 0x0152,
+        oelig: 0x0153,
+        Scaron: 0x0160,
+        scaron: 0x0161,
+        Yuml: 0x0178,
+        fnof: 0x0192,
+        circ: 0x02C6,
+        tilde: 0x02DC,
+        Alpha: 0x0391,
+        Beta: 0x0392,
+        Gamma: 0x0393,
+        Delta: 0x0394,
+        Epsilon: 0x0395,
+        Zeta: 0x0396,
+        Eta: 0x0397,
+        Theta: 0x0398,
+        Iota: 0x0399,
+        Kappa: 0x039A,
+        Lambda: 0x039B,
+        Mu: 0x039C,
+        Nu: 0x039D,
+        Xi: 0x039E,
+        Omicron: 0x039F,
+        Pi: 0x03A0,
+        Rho: 0x03A1,
+        Sigma: 0x03A3,
+        Tau: 0x03A4,
+        Upsilon: 0x03A5,
+        Phi: 0x03A6,
+        Chi: 0x03A7,
+        Psi: 0x03A8,
+        Omega: 0x03A9,
+        alpha: 0x03B1,
+        beta: 0x03B2,
+        gamma: 0x03B3,
+        delta: 0x03B4,
+        epsilon: 0x03B5,
+        zeta: 0x03B6,
+        eta: 0x03B7,
+        theta: 0x03B8,
+        iota: 0x03B9,
+        kappa: 0x03BA,
+        lambda: 0x03BB,
+        mu: 0x03BC,
+        nu: 0x03BD,
+        xi: 0x03BE,
+        omicron: 0x03BF,
+        pi: 0x03C0,
+        rho: 0x03C1,
+        sigmaf: 0x03C2,
+        sigma: 0x03C3,
+        tau: 0x03C4,
+        upsilon: 0x03C5,
+        phi: 0x03C6,
+        chi: 0x03C7,
+        psi: 0x03C8,
+        omega: 0x03C9,
+        thetasym: 0x03D1,
+        upsih: 0x03D2,
+        piv: 0x03D6,
+        ensp: 0x2002,
+        emsp: 0x2003,
+        thinsp: 0x2009,
+        zwnj: 0x200C,
+        zwj: 0x200D,
+        lrm: 0x200E,
+        rlm: 0x200F,
+        ndash: 0x2013,
+        mdash: 0x2014,
+        lsquo: 0x2018,
+        rsquo: 0x2019,
+        sbquo: 0x201A,
+        ldquo: 0x201C,
+        rdquo: 0x201D,
+        bdquo: 0x201E,
+        dagger: 0x2020,
+        Dagger: 0x2021,
+        bull: 0x2022,
+        hellip: 0x2026,
+        permil: 0x2030,
+        prime: 0x2032,
+        Prime: 0x2033,
+        lsaquo: 0x2039,
+        rsaquo: 0x203A,
+        oline: 0x203E,
+        frasl: 0x2044,
+        euro: 0x20AC,
+        image: 0x2111,
+        weierp: 0x2118,
+        real: 0x211C,
+        trade: 0x2122,
+        alefsym: 0x2135,
+        larr: 0x2190,
+        uarr: 0x2191,
+        rarr: 0x2192,
+        darr: 0x2193,
+        harr: 0x2194,
+        crarr: 0x21B5,
+        lArr: 0x21D0,
+        uArr: 0x21D1,
+        rArr: 0x21D2,
+        dArr: 0x21D3,
+        hArr: 0x21D4,
+        forall: 0x2200,
+        part: 0x2202,
+        exist: 0x2203,
+        empty: 0x2205,
+        nabla: 0x2207,
+        isin: 0x2208,
+        notin: 0x2209,
+        ni: 0x220B,
+        prod: 0x220F,
+        sum: 0x2211,
+        minus: 0x2212,
+        lowast: 0x2217,
+        radic: 0x221A,
+        prop: 0x221D,
+        infin: 0x221E,
+        ang: 0x2220,
+        and: 0x2227,
+        or: 0x2228,
+        cap: 0x2229,
+        cup: 0x222A,
+        int: 0x222B,
+        there4: 0x2234,
+        sim: 0x223C,
+        cong: 0x2245,
+        asymp: 0x2248,
+        ne: 0x2260,
+        equiv: 0x2261,
+        le: 0x2264,
+        ge: 0x2265,
+        sub: 0x2282,
+        sup: 0x2283,
+        nsub: 0x2284,
+        sube: 0x2286,
+        supe: 0x2287,
+        oplus: 0x2295,
+        otimes: 0x2297,
+        perp: 0x22A5,
+        sdot: 0x22C5,
+        lceil: 0x2308,
+        rceil: 0x2309,
+        lfloor: 0x230A,
+        rfloor: 0x230B,
+        lang: 0x2329,
+        rang: 0x232A,
+        loz: 0x25CA,
+        spades: 0x2660,
+        clubs: 0x2663,
+        hearts: 0x2665,
+        diams: 0x2666
+    });
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    function transformES2016(context) {
+        var hoistVariableDeclaration = context.hoistVariableDeclaration;
+        return ts.chainBundle(transformSourceFile);
+        function transformSourceFile(node) {
+            if (node.isDeclarationFile) {
+                return node;
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitor(node) {
+            if ((node.transformFlags & 32 /* ContainsES2016 */) === 0) {
+                return node;
+            }
+            switch (node.kind) {
+                case 200 /* BinaryExpression */:
+                    return visitBinaryExpression(node);
+                default:
+                    return ts.visitEachChild(node, visitor, context);
+            }
+        }
+        function visitBinaryExpression(node) {
+            switch (node.operatorToken.kind) {
+                case 62 /* AsteriskAsteriskEqualsToken */:
+                    return visitExponentiationAssignmentExpression(node);
+                case 40 /* AsteriskAsteriskToken */:
+                    return visitExponentiationExpression(node);
+                default:
+                    return ts.visitEachChild(node, visitor, context);
+            }
+        }
+        function visitExponentiationAssignmentExpression(node) {
+            var target;
+            var value;
+            var left = ts.visitNode(node.left, visitor, ts.isExpression);
+            var right = ts.visitNode(node.right, visitor, ts.isExpression);
+            if (ts.isElementAccessExpression(left)) {
+                // Transforms `a[x] **= b` into `(_a = a)[_x = x] = Math.pow(_a[_x], b)`
+                var expressionTemp = ts.createTempVariable(hoistVariableDeclaration);
+                var argumentExpressionTemp = ts.createTempVariable(hoistVariableDeclaration);
+                target = ts.setTextRange(ts.createElementAccess(ts.setTextRange(ts.createAssignment(expressionTemp, left.expression), left.expression), ts.setTextRange(ts.createAssignment(argumentExpressionTemp, left.argumentExpression), left.argumentExpression)), left);
+                value = ts.setTextRange(ts.createElementAccess(expressionTemp, argumentExpressionTemp), left);
+            }
+            else if (ts.isPropertyAccessExpression(left)) {
+                // Transforms `a.x **= b` into `(_a = a).x = Math.pow(_a.x, b)`
+                var expressionTemp = ts.createTempVariable(hoistVariableDeclaration);
+                target = ts.setTextRange(ts.createPropertyAccess(ts.setTextRange(ts.createAssignment(expressionTemp, left.expression), left.expression), left.name), left);
+                value = ts.setTextRange(ts.createPropertyAccess(expressionTemp, left.name), left);
+            }
+            else {
+                // Transforms `a **= b` into `a = Math.pow(a, b)`
+                target = left;
+                value = left;
+            }
+            return ts.setTextRange(ts.createAssignment(target, ts.createMathPow(value, right, /*location*/ node)), node);
+        }
+        function visitExponentiationExpression(node) {
+            // Transforms `a ** b` into `Math.pow(a, b)`
+            var left = ts.visitNode(node.left, visitor, ts.isExpression);
+            var right = ts.visitNode(node.right, visitor, ts.isExpression);
+            return ts.createMathPow(left, right, /*location*/ node);
+        }
+    }
+    ts.transformES2016 = transformES2016;
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    var ES2015SubstitutionFlags;
+    (function (ES2015SubstitutionFlags) {
+        /** Enables substitutions for captured `this` */
+        ES2015SubstitutionFlags[ES2015SubstitutionFlags["CapturedThis"] = 1] = "CapturedThis";
+        /** Enables substitutions for block-scoped bindings. */
+        ES2015SubstitutionFlags[ES2015SubstitutionFlags["BlockScopedBindings"] = 2] = "BlockScopedBindings";
+    })(ES2015SubstitutionFlags || (ES2015SubstitutionFlags = {}));
+    var CopyDirection;
+    (function (CopyDirection) {
+        CopyDirection[CopyDirection["ToOriginal"] = 0] = "ToOriginal";
+        CopyDirection[CopyDirection["ToOutParameter"] = 1] = "ToOutParameter";
+    })(CopyDirection || (CopyDirection = {}));
+    var Jump;
+    (function (Jump) {
+        Jump[Jump["Break"] = 2] = "Break";
+        Jump[Jump["Continue"] = 4] = "Continue";
+        Jump[Jump["Return"] = 8] = "Return";
+    })(Jump || (Jump = {}));
+    var SuperCaptureResult;
+    (function (SuperCaptureResult) {
+        /**
+         * A capture may have been added for calls to 'super', but
+         * the caller should emit subsequent statements normally.
+         */
+        SuperCaptureResult[SuperCaptureResult["NoReplacement"] = 0] = "NoReplacement";
+        /**
+         * A call to 'super()' got replaced with a capturing statement like:
+         *
+         *  var _this = _super.call(...) || this;
+         *
+         * Callers should skip the current statement.
+         */
+        SuperCaptureResult[SuperCaptureResult["ReplaceSuperCapture"] = 1] = "ReplaceSuperCapture";
+        /**
+         * A call to 'super()' got replaced with a capturing statement like:
+         *
+         *  return _super.call(...) || this;
+         *
+         * Callers should skip the current statement and avoid any returns of '_this'.
+         */
+        SuperCaptureResult[SuperCaptureResult["ReplaceWithReturn"] = 2] = "ReplaceWithReturn";
+    })(SuperCaptureResult || (SuperCaptureResult = {}));
+    // Facts we track as we traverse the tree
+    var HierarchyFacts;
+    (function (HierarchyFacts) {
+        HierarchyFacts[HierarchyFacts["None"] = 0] = "None";
+        //
+        // Ancestor facts
+        //
+        HierarchyFacts[HierarchyFacts["Function"] = 1] = "Function";
+        HierarchyFacts[HierarchyFacts["ArrowFunction"] = 2] = "ArrowFunction";
+        HierarchyFacts[HierarchyFacts["AsyncFunctionBody"] = 4] = "AsyncFunctionBody";
+        HierarchyFacts[HierarchyFacts["NonStaticClassElement"] = 8] = "NonStaticClassElement";
+        HierarchyFacts[HierarchyFacts["CapturesThis"] = 16] = "CapturesThis";
+        HierarchyFacts[HierarchyFacts["ExportedVariableStatement"] = 32] = "ExportedVariableStatement";
+        HierarchyFacts[HierarchyFacts["TopLevel"] = 64] = "TopLevel";
+        HierarchyFacts[HierarchyFacts["Block"] = 128] = "Block";
+        HierarchyFacts[HierarchyFacts["IterationStatement"] = 256] = "IterationStatement";
+        HierarchyFacts[HierarchyFacts["IterationStatementBlock"] = 512] = "IterationStatementBlock";
+        HierarchyFacts[HierarchyFacts["ForStatement"] = 1024] = "ForStatement";
+        HierarchyFacts[HierarchyFacts["ForInOrForOfStatement"] = 2048] = "ForInOrForOfStatement";
+        HierarchyFacts[HierarchyFacts["ConstructorWithCapturedSuper"] = 4096] = "ConstructorWithCapturedSuper";
+        HierarchyFacts[HierarchyFacts["ComputedPropertyName"] = 8192] = "ComputedPropertyName";
+        // NOTE: do not add more ancestor flags without also updating AncestorFactsMask below.
+        //
+        // Ancestor masks
+        //
+        HierarchyFacts[HierarchyFacts["AncestorFactsMask"] = 16383] = "AncestorFactsMask";
+        // We are always in *some* kind of block scope, but only specific block-scope containers are
+        // top-level or Blocks.
+        HierarchyFacts[HierarchyFacts["BlockScopeIncludes"] = 0] = "BlockScopeIncludes";
+        HierarchyFacts[HierarchyFacts["BlockScopeExcludes"] = 4032] = "BlockScopeExcludes";
+        // A source file is a top-level block scope.
+        HierarchyFacts[HierarchyFacts["SourceFileIncludes"] = 64] = "SourceFileIncludes";
+        HierarchyFacts[HierarchyFacts["SourceFileExcludes"] = 3968] = "SourceFileExcludes";
+        // Functions, methods, and accessors are both new lexical scopes and new block scopes.
+        HierarchyFacts[HierarchyFacts["FunctionIncludes"] = 65] = "FunctionIncludes";
+        HierarchyFacts[HierarchyFacts["FunctionExcludes"] = 16286] = "FunctionExcludes";
+        HierarchyFacts[HierarchyFacts["AsyncFunctionBodyIncludes"] = 69] = "AsyncFunctionBodyIncludes";
+        HierarchyFacts[HierarchyFacts["AsyncFunctionBodyExcludes"] = 16278] = "AsyncFunctionBodyExcludes";
+        // Arrow functions are lexically scoped to their container, but are new block scopes.
+        HierarchyFacts[HierarchyFacts["ArrowFunctionIncludes"] = 66] = "ArrowFunctionIncludes";
+        HierarchyFacts[HierarchyFacts["ArrowFunctionExcludes"] = 16256] = "ArrowFunctionExcludes";
+        // Constructors are both new lexical scopes and new block scopes. Constructors are also
+        // always considered non-static members of a class.
+        HierarchyFacts[HierarchyFacts["ConstructorIncludes"] = 73] = "ConstructorIncludes";
+        HierarchyFacts[HierarchyFacts["ConstructorExcludes"] = 16278] = "ConstructorExcludes";
+        // 'do' and 'while' statements are not block scopes. We track that the subtree is contained
+        // within an IterationStatement to indicate whether the embedded statement is an
+        // IterationStatementBlock.
+        HierarchyFacts[HierarchyFacts["DoOrWhileStatementIncludes"] = 256] = "DoOrWhileStatementIncludes";
+        HierarchyFacts[HierarchyFacts["DoOrWhileStatementExcludes"] = 0] = "DoOrWhileStatementExcludes";
+        // 'for' statements are new block scopes and have special handling for 'let' declarations.
+        HierarchyFacts[HierarchyFacts["ForStatementIncludes"] = 1280] = "ForStatementIncludes";
+        HierarchyFacts[HierarchyFacts["ForStatementExcludes"] = 3008] = "ForStatementExcludes";
+        // 'for-in' and 'for-of' statements are new block scopes and have special handling for
+        // 'let' declarations.
+        HierarchyFacts[HierarchyFacts["ForInOrForOfStatementIncludes"] = 2304] = "ForInOrForOfStatementIncludes";
+        HierarchyFacts[HierarchyFacts["ForInOrForOfStatementExcludes"] = 1984] = "ForInOrForOfStatementExcludes";
+        // Blocks (other than function bodies) are new block scopes.
+        HierarchyFacts[HierarchyFacts["BlockIncludes"] = 128] = "BlockIncludes";
+        HierarchyFacts[HierarchyFacts["BlockExcludes"] = 3904] = "BlockExcludes";
+        HierarchyFacts[HierarchyFacts["IterationStatementBlockIncludes"] = 512] = "IterationStatementBlockIncludes";
+        HierarchyFacts[HierarchyFacts["IterationStatementBlockExcludes"] = 4032] = "IterationStatementBlockExcludes";
+        // Computed property names track subtree flags differently than their containing members.
+        HierarchyFacts[HierarchyFacts["ComputedPropertyNameIncludes"] = 8192] = "ComputedPropertyNameIncludes";
+        HierarchyFacts[HierarchyFacts["ComputedPropertyNameExcludes"] = 0] = "ComputedPropertyNameExcludes";
+        //
+        // Subtree facts
+        //
+        HierarchyFacts[HierarchyFacts["NewTarget"] = 16384] = "NewTarget";
+        HierarchyFacts[HierarchyFacts["NewTargetInComputedPropertyName"] = 32768] = "NewTargetInComputedPropertyName";
+        //
+        // Subtree masks
+        //
+        HierarchyFacts[HierarchyFacts["SubtreeFactsMask"] = -16384] = "SubtreeFactsMask";
+        HierarchyFacts[HierarchyFacts["PropagateNewTargetMask"] = 49152] = "PropagateNewTargetMask";
+    })(HierarchyFacts || (HierarchyFacts = {}));
+    function transformES2015(context) {
+        var startLexicalEnvironment = context.startLexicalEnvironment, resumeLexicalEnvironment = context.resumeLexicalEnvironment, endLexicalEnvironment = context.endLexicalEnvironment, hoistVariableDeclaration = context.hoistVariableDeclaration;
+        var compilerOptions = context.getCompilerOptions();
+        var resolver = context.getEmitResolver();
+        var previousOnSubstituteNode = context.onSubstituteNode;
+        var previousOnEmitNode = context.onEmitNode;
+        context.onEmitNode = onEmitNode;
+        context.onSubstituteNode = onSubstituteNode;
+        var currentSourceFile;
+        var currentText;
+        var hierarchyFacts;
+        var taggedTemplateStringDeclarations;
+        function recordTaggedTemplateString(temp) {
+            taggedTemplateStringDeclarations = ts.append(taggedTemplateStringDeclarations, ts.createVariableDeclaration(temp));
+        }
+        /**
+         * Used to track if we are emitting body of the converted loop
+         */
+        var convertedLoopState;
+        /**
+         * Keeps track of whether substitutions have been enabled for specific cases.
+         * They are persisted between each SourceFile transformation and should not
+         * be reset.
+         */
+        var enabledSubstitutions;
+        return ts.chainBundle(transformSourceFile);
+        function transformSourceFile(node) {
+            if (node.isDeclarationFile) {
+                return node;
+            }
+            currentSourceFile = node;
+            currentText = node.text;
+            var visited = visitSourceFile(node);
+            ts.addEmitHelpers(visited, context.readEmitHelpers());
+            currentSourceFile = undefined;
+            currentText = undefined;
+            taggedTemplateStringDeclarations = undefined;
+            hierarchyFacts = 0 /* None */;
+            return visited;
+        }
+        /**
+         * Sets the `HierarchyFacts` for this node prior to visiting this node's subtree, returning the facts set prior to modification.
+         * @param excludeFacts The existing `HierarchyFacts` to reset before visiting the subtree.
+         * @param includeFacts The new `HierarchyFacts` to set before visiting the subtree.
+         */
+        function enterSubtree(excludeFacts, includeFacts) {
+            var ancestorFacts = hierarchyFacts;
+            hierarchyFacts = (hierarchyFacts & ~excludeFacts | includeFacts) & 16383 /* AncestorFactsMask */;
+            return ancestorFacts;
+        }
+        /**
+         * Restores the `HierarchyFacts` for this node's ancestor after visiting this node's
+         * subtree, propagating specific facts from the subtree.
+         * @param ancestorFacts The `HierarchyFacts` of the ancestor to restore after visiting the subtree.
+         * @param excludeFacts The existing `HierarchyFacts` of the subtree that should not be propagated.
+         * @param includeFacts The new `HierarchyFacts` of the subtree that should be propagated.
+         */
+        function exitSubtree(ancestorFacts, excludeFacts, includeFacts) {
+            hierarchyFacts = (hierarchyFacts & ~excludeFacts | includeFacts) & -16384 /* SubtreeFactsMask */ | ancestorFacts;
+        }
+        function isReturnVoidStatementInConstructorWithCapturedSuper(node) {
+            return (hierarchyFacts & 4096 /* ConstructorWithCapturedSuper */) !== 0
+                && node.kind === 225 /* ReturnStatement */
+                && !node.expression;
+        }
+        function shouldVisitNode(node) {
+            return (node.transformFlags & 128 /* ContainsES2015 */) !== 0
+                || convertedLoopState !== undefined
+                || (hierarchyFacts & 4096 /* ConstructorWithCapturedSuper */ && (ts.isStatement(node) || (node.kind === 213 /* Block */)))
+                || (ts.isIterationStatement(node, /*lookInLabeledStatements*/ false) && shouldConvertIterationStatementBody(node))
+                || (ts.getEmitFlags(node) & 33554432 /* TypeScriptClassWrapper */) !== 0;
+        }
+        function visitor(node) {
+            if (shouldVisitNode(node)) {
+                return visitJavaScript(node);
+            }
+            else {
+                return node;
+            }
+        }
+        function functionBodyVisitor(node) {
+            if (shouldVisitNode(node)) {
+                return visitBlock(node, /*isFunctionBody*/ true);
+            }
+            return node;
+        }
+        function callExpressionVisitor(node) {
+            if (node.kind === 97 /* SuperKeyword */) {
+                return visitSuperKeyword(/*isExpressionOfCall*/ true);
+            }
+            return visitor(node);
+        }
+        function visitJavaScript(node) {
+            switch (node.kind) {
+                case 115 /* StaticKeyword */:
+                    return undefined; // elide static keyword
+                case 235 /* ClassDeclaration */:
+                    return visitClassDeclaration(node);
+                case 205 /* ClassExpression */:
+                    return visitClassExpression(node);
+                case 149 /* Parameter */:
+                    return visitParameter(node);
+                case 234 /* FunctionDeclaration */:
+                    return visitFunctionDeclaration(node);
+                case 193 /* ArrowFunction */:
+                    return visitArrowFunction(node);
+                case 192 /* FunctionExpression */:
+                    return visitFunctionExpression(node);
+                case 232 /* VariableDeclaration */:
+                    return visitVariableDeclaration(node);
+                case 71 /* Identifier */:
+                    return visitIdentifier(node);
+                case 233 /* VariableDeclarationList */:
+                    return visitVariableDeclarationList(node);
+                case 227 /* SwitchStatement */:
+                    return visitSwitchStatement(node);
+                case 241 /* CaseBlock */:
+                    return visitCaseBlock(node);
+                case 213 /* Block */:
+                    return visitBlock(node, /*isFunctionBody*/ false);
+                case 224 /* BreakStatement */:
+                case 223 /* ContinueStatement */:
+                    return visitBreakOrContinueStatement(node);
+                case 228 /* LabeledStatement */:
+                    return visitLabeledStatement(node);
+                case 218 /* DoStatement */:
+                case 219 /* WhileStatement */:
+                    return visitDoOrWhileStatement(node, /*outermostLabeledStatement*/ undefined);
+                case 220 /* ForStatement */:
+                    return visitForStatement(node, /*outermostLabeledStatement*/ undefined);
+                case 221 /* ForInStatement */:
+                    return visitForInStatement(node, /*outermostLabeledStatement*/ undefined);
+                case 222 /* ForOfStatement */:
+                    return visitForOfStatement(node, /*outermostLabeledStatement*/ undefined);
+                case 216 /* ExpressionStatement */:
+                    return visitExpressionStatement(node);
+                case 184 /* ObjectLiteralExpression */:
+                    return visitObjectLiteralExpression(node);
+                case 269 /* CatchClause */:
+                    return visitCatchClause(node);
+                case 271 /* ShorthandPropertyAssignment */:
+                    return visitShorthandPropertyAssignment(node);
+                case 147 /* ComputedPropertyName */:
+                    return visitComputedPropertyName(node);
+                case 183 /* ArrayLiteralExpression */:
+                    return visitArrayLiteralExpression(node);
+                case 187 /* CallExpression */:
+                    return visitCallExpression(node);
+                case 188 /* NewExpression */:
+                    return visitNewExpression(node);
+                case 191 /* ParenthesizedExpression */:
+                    return visitParenthesizedExpression(node, /*needsDestructuringValue*/ true);
+                case 200 /* BinaryExpression */:
+                    return visitBinaryExpression(node, /*needsDestructuringValue*/ true);
+                case 13 /* NoSubstitutionTemplateLiteral */:
+                case 14 /* TemplateHead */:
+                case 15 /* TemplateMiddle */:
+                case 16 /* TemplateTail */:
+                    return visitTemplateLiteral(node);
+                case 9 /* StringLiteral */:
+                    return visitStringLiteral(node);
+                case 8 /* NumericLiteral */:
+                    return visitNumericLiteral(node);
+                case 189 /* TaggedTemplateExpression */:
+                    return visitTaggedTemplateExpression(node);
+                case 202 /* TemplateExpression */:
+                    return visitTemplateExpression(node);
+                case 203 /* YieldExpression */:
+                    return visitYieldExpression(node);
+                case 204 /* SpreadElement */:
+                    return visitSpreadElement(node);
+                case 97 /* SuperKeyword */:
+                    return visitSuperKeyword(/*isExpressionOfCall*/ false);
+                case 99 /* ThisKeyword */:
+                    return visitThisKeyword(node);
+                case 210 /* MetaProperty */:
+                    return visitMetaProperty(node);
+                case 154 /* MethodDeclaration */:
+                    return visitMethodDeclaration(node);
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                    return visitAccessorDeclaration(node);
+                case 214 /* VariableStatement */:
+                    return visitVariableStatement(node);
+                case 225 /* ReturnStatement */:
+                    return visitReturnStatement(node);
+                default:
+                    return ts.visitEachChild(node, visitor, context);
+            }
+        }
+        function visitSourceFile(node) {
+            var ancestorFacts = enterSubtree(3968 /* SourceFileExcludes */, 64 /* SourceFileIncludes */);
+            var statements = [];
+            startLexicalEnvironment();
+            var statementOffset = ts.addStandardPrologue(statements, node.statements, /*ensureUseStrict*/ false);
+            addCaptureThisForNodeIfNeeded(statements, node);
+            statementOffset = ts.addCustomPrologue(statements, node.statements, statementOffset, visitor);
+            ts.addRange(statements, ts.visitNodes(node.statements, visitor, ts.isStatement, statementOffset));
+            if (taggedTemplateStringDeclarations) {
+                statements.push(ts.createVariableStatement(/*modifiers*/ undefined, ts.createVariableDeclarationList(taggedTemplateStringDeclarations)));
+            }
+            ts.prependStatements(statements, endLexicalEnvironment());
+            exitSubtree(ancestorFacts, 0 /* None */, 0 /* None */);
+            return ts.updateSourceFileNode(node, ts.setTextRange(ts.createNodeArray(statements), node.statements));
+        }
+        function visitSwitchStatement(node) {
+            if (convertedLoopState !== undefined) {
+                var savedAllowedNonLabeledJumps = convertedLoopState.allowedNonLabeledJumps;
+                // for switch statement allow only non-labeled break
+                convertedLoopState.allowedNonLabeledJumps |= 2 /* Break */;
+                var result = ts.visitEachChild(node, visitor, context);
+                convertedLoopState.allowedNonLabeledJumps = savedAllowedNonLabeledJumps;
+                return result;
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitCaseBlock(node) {
+            var ancestorFacts = enterSubtree(4032 /* BlockScopeExcludes */, 0 /* BlockScopeIncludes */);
+            var updated = ts.visitEachChild(node, visitor, context);
+            exitSubtree(ancestorFacts, 0 /* None */, 0 /* None */);
+            return updated;
+        }
+        function returnCapturedThis(node) {
+            return ts.setOriginalNode(ts.createReturn(ts.createFileLevelUniqueName("_this")), node);
+        }
+        function visitReturnStatement(node) {
+            if (convertedLoopState) {
+                convertedLoopState.nonLocalJumps |= 8 /* Return */;
+                if (isReturnVoidStatementInConstructorWithCapturedSuper(node)) {
+                    node = returnCapturedThis(node);
+                }
+                return ts.createReturn(ts.createObjectLiteral([
+                    ts.createPropertyAssignment(ts.createIdentifier("value"), node.expression
+                        ? ts.visitNode(node.expression, visitor, ts.isExpression)
+                        : ts.createVoidZero())
+                ]));
+            }
+            else if (isReturnVoidStatementInConstructorWithCapturedSuper(node)) {
+                return returnCapturedThis(node);
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitThisKeyword(node) {
+            if (convertedLoopState) {
+                if (hierarchyFacts & 2 /* ArrowFunction */) {
+                    // if the enclosing function is an ArrowFunction then we use the captured 'this' keyword.
+                    convertedLoopState.containsLexicalThis = true;
+                    return node;
+                }
+                return convertedLoopState.thisName || (convertedLoopState.thisName = ts.createUniqueName("this"));
+            }
+            return node;
+        }
+        function visitIdentifier(node) {
+            if (!convertedLoopState) {
+                return node;
+            }
+            if (ts.isGeneratedIdentifier(node)) {
+                return node;
+            }
+            if (node.escapedText !== "arguments" || !resolver.isArgumentsLocalBinding(node)) {
+                return node;
+            }
+            return convertedLoopState.argumentsName || (convertedLoopState.argumentsName = ts.createUniqueName("arguments"));
+        }
+        function visitBreakOrContinueStatement(node) {
+            if (convertedLoopState) {
+                // check if we can emit break/continue as is
+                // it is possible if either
+                //   - break/continue is labeled and label is located inside the converted loop
+                //   - break/continue is non-labeled and located in non-converted loop/switch statement
+                var jump = node.kind === 224 /* BreakStatement */ ? 2 /* Break */ : 4 /* Continue */;
+                var canUseBreakOrContinue = (node.label && convertedLoopState.labels && convertedLoopState.labels.get(ts.idText(node.label))) ||
+                    (!node.label && (convertedLoopState.allowedNonLabeledJumps & jump));
+                if (!canUseBreakOrContinue) {
+                    var labelMarker = void 0;
+                    var label = node.label;
+                    if (!label) {
+                        if (node.kind === 224 /* BreakStatement */) {
+                            convertedLoopState.nonLocalJumps |= 2 /* Break */;
+                            labelMarker = "break";
+                        }
+                        else {
+                            convertedLoopState.nonLocalJumps |= 4 /* Continue */;
+                            // note: return value is emitted only to simplify debugging, call to converted loop body does not do any dispatching on it.
+                            labelMarker = "continue";
+                        }
+                    }
+                    else {
+                        if (node.kind === 224 /* BreakStatement */) {
+                            labelMarker = "break-" + label.escapedText;
+                            setLabeledJump(convertedLoopState, /*isBreak*/ true, ts.idText(label), labelMarker);
+                        }
+                        else {
+                            labelMarker = "continue-" + label.escapedText;
+                            setLabeledJump(convertedLoopState, /*isBreak*/ false, ts.idText(label), labelMarker);
+                        }
+                    }
+                    var returnExpression = ts.createLiteral(labelMarker);
+                    if (convertedLoopState.loopOutParameters.length) {
+                        var outParams = convertedLoopState.loopOutParameters;
+                        var expr = void 0;
+                        for (var i = 0; i < outParams.length; i++) {
+                            var copyExpr = copyOutParameter(outParams[i], 1 /* ToOutParameter */);
+                            if (i === 0) {
+                                expr = copyExpr;
+                            }
+                            else {
+                                expr = ts.createBinary(expr, 26 /* CommaToken */, copyExpr);
+                            }
+                        }
+                        returnExpression = ts.createBinary(expr, 26 /* CommaToken */, returnExpression);
+                    }
+                    return ts.createReturn(returnExpression);
+                }
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        /**
+         * Visits a ClassDeclaration and transforms it into a variable statement.
+         *
+         * @param node A ClassDeclaration node.
+         */
+        function visitClassDeclaration(node) {
+            // [source]
+            //      class C { }
+            //
+            // [output]
+            //      var C = (function () {
+            //          function C() {
+            //          }
+            //          return C;
+            //      }());
+            var variable = ts.createVariableDeclaration(ts.getLocalName(node, /*allowComments*/ true), 
+            /*type*/ undefined, transformClassLikeDeclarationToExpression(node));
+            ts.setOriginalNode(variable, node);
+            var statements = [];
+            var statement = ts.createVariableStatement(/*modifiers*/ undefined, ts.createVariableDeclarationList([variable]));
+            ts.setOriginalNode(statement, node);
+            ts.setTextRange(statement, node);
+            ts.startOnNewLine(statement);
+            statements.push(statement);
+            // Add an `export default` statement for default exports (for `--target es5 --module es6`)
+            if (ts.hasModifier(node, 1 /* Export */)) {
+                var exportStatement = ts.hasModifier(node, 512 /* Default */)
+                    ? ts.createExportDefault(ts.getLocalName(node))
+                    : ts.createExternalModuleExport(ts.getLocalName(node));
+                ts.setOriginalNode(exportStatement, statement);
+                statements.push(exportStatement);
+            }
+            var emitFlags = ts.getEmitFlags(node);
+            if ((emitFlags & 4194304 /* HasEndOfDeclarationMarker */) === 0) {
+                // Add a DeclarationMarker as a marker for the end of the declaration
+                statements.push(ts.createEndOfDeclarationMarker(node));
+                ts.setEmitFlags(statement, emitFlags | 4194304 /* HasEndOfDeclarationMarker */);
+            }
+            return ts.singleOrMany(statements);
+        }
+        /**
+         * Visits a ClassExpression and transforms it into an expression.
+         *
+         * @param node A ClassExpression node.
+         */
+        function visitClassExpression(node) {
+            // [source]
+            //      C = class { }
+            //
+            // [output]
+            //      C = (function () {
+            //          function class_1() {
+            //          }
+            //          return class_1;
+            //      }())
+            return transformClassLikeDeclarationToExpression(node);
+        }
+        /**
+         * Transforms a ClassExpression or ClassDeclaration into an expression.
+         *
+         * @param node A ClassExpression or ClassDeclaration node.
+         */
+        function transformClassLikeDeclarationToExpression(node) {
+            // [source]
+            //      class C extends D {
+            //          constructor() {}
+            //          method() {}
+            //          get prop() {}
+            //          set prop(v) {}
+            //      }
+            //
+            // [output]
+            //      (function (_super) {
+            //          __extends(C, _super);
+            //          function C() {
+            //          }
+            //          C.prototype.method = function () {}
+            //          Object.defineProperty(C.prototype, "prop", {
+            //              get: function() {},
+            //              set: function() {},
+            //              enumerable: true,
+            //              configurable: true
+            //          });
+            //          return C;
+            //      }(D))
+            if (node.name) {
+                enableSubstitutionsForBlockScopedBindings();
+            }
+            var extendsClauseElement = ts.getClassExtendsHeritageClauseElement(node);
+            var classFunction = ts.createFunctionExpression(
+            /*modifiers*/ undefined, 
+            /*asteriskToken*/ undefined, 
+            /*name*/ undefined, 
+            /*typeParameters*/ undefined, extendsClauseElement ? [ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, ts.createFileLevelUniqueName("_super"))] : [], 
+            /*type*/ undefined, transformClassBody(node, extendsClauseElement));
+            // To preserve the behavior of the old emitter, we explicitly indent
+            // the body of the function here if it was requested in an earlier
+            // transformation.
+            ts.setEmitFlags(classFunction, (ts.getEmitFlags(node) & 65536 /* Indented */) | 524288 /* ReuseTempVariableScope */);
+            // "inner" and "outer" below are added purely to preserve source map locations from
+            // the old emitter
+            var inner = ts.createPartiallyEmittedExpression(classFunction);
+            inner.end = node.end;
+            ts.setEmitFlags(inner, 1536 /* NoComments */);
+            var outer = ts.createPartiallyEmittedExpression(inner);
+            outer.end = ts.skipTrivia(currentText, node.pos);
+            ts.setEmitFlags(outer, 1536 /* NoComments */);
+            var result = ts.createParen(ts.createCall(outer, 
+            /*typeArguments*/ undefined, extendsClauseElement
+                ? [ts.visitNode(extendsClauseElement.expression, visitor, ts.isExpression)]
+                : []));
+            ts.addSyntheticLeadingComment(result, 3 /* MultiLineCommentTrivia */, "* @class ");
+            return result;
+        }
+        /**
+         * Transforms a ClassExpression or ClassDeclaration into a function body.
+         *
+         * @param node A ClassExpression or ClassDeclaration node.
+         * @param extendsClauseElement The expression for the class `extends` clause.
+         */
+        function transformClassBody(node, extendsClauseElement) {
+            var statements = [];
+            startLexicalEnvironment();
+            addExtendsHelperIfNeeded(statements, node, extendsClauseElement);
+            addConstructor(statements, node, extendsClauseElement);
+            addClassMembers(statements, node);
+            // Create a synthetic text range for the return statement.
+            var closingBraceLocation = ts.createTokenRange(ts.skipTrivia(currentText, node.members.end), 18 /* CloseBraceToken */);
+            var localName = ts.getInternalName(node);
+            // The following partially-emitted expression exists purely to align our sourcemap
+            // emit with the original emitter.
+            var outer = ts.createPartiallyEmittedExpression(localName);
+            outer.end = closingBraceLocation.end;
+            ts.setEmitFlags(outer, 1536 /* NoComments */);
+            var statement = ts.createReturn(outer);
+            statement.pos = closingBraceLocation.pos;
+            ts.setEmitFlags(statement, 1536 /* NoComments */ | 384 /* NoTokenSourceMaps */);
+            statements.push(statement);
+            ts.prependStatements(statements, endLexicalEnvironment());
+            var block = ts.createBlock(ts.setTextRange(ts.createNodeArray(statements), /*location*/ node.members), /*multiLine*/ true);
+            ts.setEmitFlags(block, 1536 /* NoComments */);
+            return block;
+        }
+        /**
+         * Adds a call to the `__extends` helper if needed for a class.
+         *
+         * @param statements The statements of the class body function.
+         * @param node The ClassExpression or ClassDeclaration node.
+         * @param extendsClauseElement The expression for the class `extends` clause.
+         */
+        function addExtendsHelperIfNeeded(statements, node, extendsClauseElement) {
+            if (extendsClauseElement) {
+                statements.push(ts.setTextRange(ts.createStatement(createExtendsHelper(context, ts.getInternalName(node))), 
+                /*location*/ extendsClauseElement));
+            }
+        }
+        /**
+         * Adds the constructor of the class to a class body function.
+         *
+         * @param statements The statements of the class body function.
+         * @param node The ClassExpression or ClassDeclaration node.
+         * @param extendsClauseElement The expression for the class `extends` clause.
+         */
+        function addConstructor(statements, node, extendsClauseElement) {
+            var savedConvertedLoopState = convertedLoopState;
+            convertedLoopState = undefined;
+            var ancestorFacts = enterSubtree(16278 /* ConstructorExcludes */, 73 /* ConstructorIncludes */);
+            var constructor = ts.getFirstConstructorWithBody(node);
+            var hasSynthesizedSuper = hasSynthesizedDefaultSuperCall(constructor, extendsClauseElement !== undefined);
+            var constructorFunction = ts.createFunctionDeclaration(
+            /*decorators*/ undefined, 
+            /*modifiers*/ undefined, 
+            /*asteriskToken*/ undefined, ts.getInternalName(node), 
+            /*typeParameters*/ undefined, transformConstructorParameters(constructor, hasSynthesizedSuper), 
+            /*type*/ undefined, transformConstructorBody(constructor, node, extendsClauseElement, hasSynthesizedSuper));
+            ts.setTextRange(constructorFunction, constructor || node);
+            if (extendsClauseElement) {
+                ts.setEmitFlags(constructorFunction, 8 /* CapturesThis */);
+            }
+            statements.push(constructorFunction);
+            exitSubtree(ancestorFacts, 49152 /* PropagateNewTargetMask */, 0 /* None */);
+            convertedLoopState = savedConvertedLoopState;
+        }
+        /**
+         * Transforms the parameters of the constructor declaration of a class.
+         *
+         * @param constructor The constructor for the class.
+         * @param hasSynthesizedSuper A value indicating whether the constructor starts with a
+         *                            synthesized `super` call.
+         */
+        function transformConstructorParameters(constructor, hasSynthesizedSuper) {
+            // If the TypeScript transformer needed to synthesize a constructor for property
+            // initializers, it would have also added a synthetic `...args` parameter and
+            // `super` call.
+            // If this is the case, we do not include the synthetic `...args` parameter and
+            // will instead use the `arguments` object in ES5/3.
+            return ts.visitParameterList(constructor && !hasSynthesizedSuper ? constructor.parameters : undefined, visitor, context)
+                || [];
+        }
+        /**
+         * Transforms the body of a constructor declaration of a class.
+         *
+         * @param constructor The constructor for the class.
+         * @param node The node which contains the constructor.
+         * @param extendsClauseElement The expression for the class `extends` clause.
+         * @param hasSynthesizedSuper A value indicating whether the constructor starts with a
+         *                            synthesized `super` call.
+         */
+        function transformConstructorBody(constructor, node, extendsClauseElement, hasSynthesizedSuper) {
+            var statements = [];
+            resumeLexicalEnvironment();
+            var statementOffset = -1;
+            if (hasSynthesizedSuper) {
+                // If a super call has already been synthesized,
+                // we're going to assume that we should just transform everything after that.
+                // The assumption is that no prior step in the pipeline has added any prologue directives.
+                statementOffset = 0;
+            }
+            else if (constructor) {
+                statementOffset = ts.addStandardPrologue(statements, constructor.body.statements, /*ensureUseStrict*/ false);
+            }
+            if (constructor) {
+                addDefaultValueAssignmentsIfNeeded(statements, constructor);
+                addRestParameterIfNeeded(statements, constructor, hasSynthesizedSuper);
+                if (!hasSynthesizedSuper) {
+                    // If no super call has been synthesized, emit custom prologue directives.
+                    statementOffset = ts.addCustomPrologue(statements, constructor.body.statements, statementOffset, visitor);
+                }
+                ts.Debug.assert(statementOffset >= 0, "statementOffset not initialized correctly!");
+            }
+            // determine whether the class is known syntactically to be a derived class (e.g. a
+            // class that extends a value that is not syntactically known to be `null`).
+            var isDerivedClass = !!extendsClauseElement && ts.skipOuterExpressions(extendsClauseElement.expression).kind !== 95 /* NullKeyword */;
+            var superCaptureStatus = declareOrCaptureOrReturnThisForConstructorIfNeeded(statements, constructor, isDerivedClass, hasSynthesizedSuper, statementOffset);
+            // The last statement expression was replaced. Skip it.
+            if (superCaptureStatus === 1 /* ReplaceSuperCapture */ || superCaptureStatus === 2 /* ReplaceWithReturn */) {
+                statementOffset++;
+            }
+            if (constructor) {
+                if (superCaptureStatus === 1 /* ReplaceSuperCapture */) {
+                    hierarchyFacts |= 4096 /* ConstructorWithCapturedSuper */;
+                }
+                ts.addRange(statements, ts.visitNodes(constructor.body.statements, visitor, ts.isStatement, /*start*/ statementOffset));
+            }
+            // Return `_this` unless we're sure enough that it would be pointless to add a return statement.
+            // If there's a constructor that we can tell returns in enough places, then we *do not* want to add a return.
+            if (isDerivedClass
+                && superCaptureStatus !== 2 /* ReplaceWithReturn */
+                && !(constructor && isSufficientlyCoveredByReturnStatements(constructor.body))) {
+                statements.push(ts.createReturn(ts.createFileLevelUniqueName("_this")));
+            }
+            ts.prependStatements(statements, endLexicalEnvironment());
+            if (constructor) {
+                prependCaptureNewTargetIfNeeded(statements, constructor, /*copyOnWrite*/ false);
+            }
+            var block = ts.createBlock(ts.setTextRange(ts.createNodeArray(statements), 
+            /*location*/ constructor ? constructor.body.statements : node.members), 
+            /*multiLine*/ true);
+            ts.setTextRange(block, constructor ? constructor.body : node);
+            if (!constructor) {
+                ts.setEmitFlags(block, 1536 /* NoComments */);
+            }
+            return block;
+        }
+        /**
+         * We want to try to avoid emitting a return statement in certain cases if a user already returned something.
+         * It would generate obviously dead code, so we'll try to make things a little bit prettier
+         * by doing a minimal check on whether some common patterns always explicitly return.
+         */
+        function isSufficientlyCoveredByReturnStatements(statement) {
+            // A return statement is considered covered.
+            if (statement.kind === 225 /* ReturnStatement */) {
+                return true;
+            }
+            // An if-statement with two covered branches is covered.
+            else if (statement.kind === 217 /* IfStatement */) {
+                var ifStatement = statement;
+                if (ifStatement.elseStatement) {
+                    return isSufficientlyCoveredByReturnStatements(ifStatement.thenStatement) &&
+                        isSufficientlyCoveredByReturnStatements(ifStatement.elseStatement);
+                }
+            }
+            // A block is covered if it has a last statement which is covered.
+            else if (statement.kind === 213 /* Block */) {
+                var lastStatement = ts.lastOrUndefined(statement.statements);
+                if (lastStatement && isSufficientlyCoveredByReturnStatements(lastStatement)) {
+                    return true;
+                }
+            }
+            return false;
+        }
+        /**
+         * Declares a `_this` variable for derived classes and for when arrow functions capture `this`.
+         *
+         * @returns The new statement offset into the `statements` array.
+         */
+        function declareOrCaptureOrReturnThisForConstructorIfNeeded(statements, ctor, isDerivedClass, hasSynthesizedSuper, statementOffset) {
+            // If this isn't a derived class, just capture 'this' for arrow functions if necessary.
+            if (!isDerivedClass) {
+                if (ctor) {
+                    addCaptureThisForNodeIfNeeded(statements, ctor);
+                }
+                return 0 /* NoReplacement */;
+            }
+            // We must be here because the user didn't write a constructor
+            // but we needed to call 'super(...args)' anyway as per 14.5.14 of the ES2016 spec.
+            // If that's the case we can just immediately return the result of a 'super()' call.
+            if (!ctor) {
+                statements.push(ts.createReturn(createDefaultSuperCallOrThis()));
+                return 2 /* ReplaceWithReturn */;
+            }
+            // The constructor exists, but it and the 'super()' call it contains were generated
+            // for something like property initializers.
+            // Create a captured '_this' variable and assume it will subsequently be used.
+            if (hasSynthesizedSuper) {
+                captureThisForNode(statements, ctor, createDefaultSuperCallOrThis());
+                enableSubstitutionsForCapturedThis();
+                return 1 /* ReplaceSuperCapture */;
+            }
+            // Most of the time, a 'super' call will be the first real statement in a constructor body.
+            // In these cases, we'd like to transform these into a *single* statement instead of a declaration
+            // followed by an assignment statement for '_this'. For instance, if we emitted without an initializer,
+            // we'd get:
+            //
+            //      var _this;
+            //      _this = _super.call(...) || this;
+            //
+            // instead of
+            //
+            //      var _this = _super.call(...) || this;
+            //
+            // Additionally, if the 'super()' call is the last statement, we should just avoid capturing
+            // entirely and immediately return the result like so:
+            //
+            //      return _super.call(...) || this;
+            //
+            var firstStatement;
+            var superCallExpression;
+            var ctorStatements = ctor.body.statements;
+            if (statementOffset < ctorStatements.length) {
+                firstStatement = ctorStatements[statementOffset];
+                if (firstStatement.kind === 216 /* ExpressionStatement */ && ts.isSuperCall(firstStatement.expression)) {
+                    superCallExpression = visitImmediateSuperCallInBody(firstStatement.expression);
+                }
+            }
+            // Return the result if we have an immediate super() call on the last statement,
+            // but only if the constructor itself doesn't use 'this' elsewhere.
+            if (superCallExpression
+                && statementOffset === ctorStatements.length - 1
+                && !(ctor.transformFlags & (16384 /* ContainsLexicalThis */ | 32768 /* ContainsCapturedLexicalThis */))) {
+                var returnStatement = ts.createReturn(superCallExpression);
+                if (superCallExpression.kind !== 200 /* BinaryExpression */
+                    || superCallExpression.left.kind !== 187 /* CallExpression */) {
+                    ts.Debug.fail("Assumed generated super call would have form 'super.call(...) || this'.");
+                }
+                // Shift comments from the original super call to the return statement.
+                ts.setCommentRange(returnStatement, ts.getCommentRange(ts.setEmitFlags(superCallExpression.left, 1536 /* NoComments */)));
+                statements.push(returnStatement);
+                return 2 /* ReplaceWithReturn */;
+            }
+            // Perform the capture.
+            captureThisForNode(statements, ctor, superCallExpression || createActualThis(), firstStatement);
+            // If we're actually replacing the original statement, we need to signal this to the caller.
+            if (superCallExpression) {
+                return 1 /* ReplaceSuperCapture */;
+            }
+            return 0 /* NoReplacement */;
+        }
+        function createActualThis() {
+            return ts.setEmitFlags(ts.createThis(), 4 /* NoSubstitution */);
+        }
+        function createDefaultSuperCallOrThis() {
+            return ts.createLogicalOr(ts.createLogicalAnd(ts.createStrictInequality(ts.createFileLevelUniqueName("_super"), ts.createNull()), ts.createFunctionApply(ts.createFileLevelUniqueName("_super"), createActualThis(), ts.createIdentifier("arguments"))), createActualThis());
+        }
+        /**
+         * Visits a parameter declaration.
+         *
+         * @param node A ParameterDeclaration node.
+         */
+        function visitParameter(node) {
+            if (node.dotDotDotToken) {
+                // rest parameters are elided
+                return undefined;
+            }
+            else if (ts.isBindingPattern(node.name)) {
+                // Binding patterns are converted into a generated name and are
+                // evaluated inside the function body.
+                return ts.setOriginalNode(ts.setTextRange(ts.createParameter(
+                /*decorators*/ undefined, 
+                /*modifiers*/ undefined, 
+                /*dotDotDotToken*/ undefined, ts.getGeneratedNameForNode(node), 
+                /*questionToken*/ undefined, 
+                /*type*/ undefined, 
+                /*initializer*/ undefined), 
+                /*location*/ node), 
+                /*original*/ node);
+            }
+            else if (node.initializer) {
+                // Initializers are elided
+                return ts.setOriginalNode(ts.setTextRange(ts.createParameter(
+                /*decorators*/ undefined, 
+                /*modifiers*/ undefined, 
+                /*dotDotDotToken*/ undefined, node.name, 
+                /*questionToken*/ undefined, 
+                /*type*/ undefined, 
+                /*initializer*/ undefined), 
+                /*location*/ node), 
+                /*original*/ node);
+            }
+            else {
+                return node;
+            }
+        }
+        /**
+         * Gets a value indicating whether we need to add default value assignments for a
+         * function-like node.
+         *
+         * @param node A function-like node.
+         */
+        function shouldAddDefaultValueAssignments(node) {
+            return (node.transformFlags & 131072 /* ContainsDefaultValueAssignments */) !== 0;
+        }
+        /**
+         * Adds statements to the body of a function-like node if it contains parameters with
+         * binding patterns or initializers.
+         *
+         * @param statements The statements for the new function body.
+         * @param node A function-like node.
+         */
+        function addDefaultValueAssignmentsIfNeeded(statements, node) {
+            if (!shouldAddDefaultValueAssignments(node)) {
+                return;
+            }
+            for (var _i = 0, _a = node.parameters; _i < _a.length; _i++) {
+                var parameter = _a[_i];
+                var name = parameter.name, initializer = parameter.initializer, dotDotDotToken = parameter.dotDotDotToken;
+                // A rest parameter cannot have a binding pattern or an initializer,
+                // so let's just ignore it.
+                if (dotDotDotToken) {
+                    continue;
+                }
+                if (ts.isBindingPattern(name)) {
+                    addDefaultValueAssignmentForBindingPattern(statements, parameter, name, initializer);
+                }
+                else if (initializer) {
+                    addDefaultValueAssignmentForInitializer(statements, parameter, name, initializer);
+                }
+            }
+        }
+        /**
+         * Adds statements to the body of a function-like node for parameters with binding patterns
+         *
+         * @param statements The statements for the new function body.
+         * @param parameter The parameter for the function.
+         * @param name The name of the parameter.
+         * @param initializer The initializer for the parameter.
+         */
+        function addDefaultValueAssignmentForBindingPattern(statements, parameter, name, initializer) {
+            var temp = ts.getGeneratedNameForNode(parameter);
+            // In cases where a binding pattern is simply '[]' or '{}',
+            // we usually don't want to emit a var declaration; however, in the presence
+            // of an initializer, we must emit that expression to preserve side effects.
+            if (name.elements.length > 0) {
+                statements.push(ts.setEmitFlags(ts.createVariableStatement(
+                /*modifiers*/ undefined, ts.createVariableDeclarationList(ts.flattenDestructuringBinding(parameter, visitor, context, 0 /* All */, temp))), 1048576 /* CustomPrologue */));
+            }
+            else if (initializer) {
+                statements.push(ts.setEmitFlags(ts.createStatement(ts.createAssignment(temp, ts.visitNode(initializer, visitor, ts.isExpression))), 1048576 /* CustomPrologue */));
+            }
+        }
+        /**
+         * Adds statements to the body of a function-like node for parameters with initializers.
+         *
+         * @param statements The statements for the new function body.
+         * @param parameter The parameter for the function.
+         * @param name The name of the parameter.
+         * @param initializer The initializer for the parameter.
+         */
+        function addDefaultValueAssignmentForInitializer(statements, parameter, name, initializer) {
+            initializer = ts.visitNode(initializer, visitor, ts.isExpression);
+            var statement = ts.createIf(ts.createTypeCheck(ts.getSynthesizedClone(name), "undefined"), ts.setEmitFlags(ts.setTextRange(ts.createBlock([
+                ts.createStatement(ts.setEmitFlags(ts.setTextRange(ts.createAssignment(ts.setEmitFlags(ts.getMutableClone(name), 48 /* NoSourceMap */), ts.setEmitFlags(initializer, 48 /* NoSourceMap */ | ts.getEmitFlags(initializer) | 1536 /* NoComments */)), parameter), 1536 /* NoComments */))
+            ]), parameter), 1 /* SingleLine */ | 32 /* NoTrailingSourceMap */ | 384 /* NoTokenSourceMaps */ | 1536 /* NoComments */));
+            ts.startOnNewLine(statement);
+            ts.setTextRange(statement, parameter);
+            ts.setEmitFlags(statement, 384 /* NoTokenSourceMaps */ | 32 /* NoTrailingSourceMap */ | 1048576 /* CustomPrologue */ | 1536 /* NoComments */);
+            statements.push(statement);
+        }
+        /**
+         * Gets a value indicating whether we need to add statements to handle a rest parameter.
+         *
+         * @param node A ParameterDeclaration node.
+         * @param inConstructorWithSynthesizedSuper A value indicating whether the parameter is
+         *                                          part of a constructor declaration with a
+         *                                          synthesized call to `super`
+         */
+        function shouldAddRestParameter(node, inConstructorWithSynthesizedSuper) {
+            return node && node.dotDotDotToken && node.name.kind === 71 /* Identifier */ && !inConstructorWithSynthesizedSuper;
+        }
+        /**
+         * Adds statements to the body of a function-like node if it contains a rest parameter.
+         *
+         * @param statements The statements for the new function body.
+         * @param node A function-like node.
+         * @param inConstructorWithSynthesizedSuper A value indicating whether the parameter is
+         *                                          part of a constructor declaration with a
+         *                                          synthesized call to `super`
+         */
+        function addRestParameterIfNeeded(statements, node, inConstructorWithSynthesizedSuper) {
+            var parameter = ts.lastOrUndefined(node.parameters);
+            if (!shouldAddRestParameter(parameter, inConstructorWithSynthesizedSuper)) {
+                return;
+            }
+            // `declarationName` is the name of the local declaration for the parameter.
+            var declarationName = ts.getMutableClone(parameter.name);
+            ts.setEmitFlags(declarationName, 48 /* NoSourceMap */);
+            // `expressionName` is the name of the parameter used in expressions.
+            var expressionName = ts.getSynthesizedClone(parameter.name);
+            var restIndex = node.parameters.length - 1;
+            var temp = ts.createLoopVariable();
+            // var param = [];
+            statements.push(ts.setEmitFlags(ts.setTextRange(ts.createVariableStatement(
+            /*modifiers*/ undefined, ts.createVariableDeclarationList([
+                ts.createVariableDeclaration(declarationName, 
+                /*type*/ undefined, ts.createArrayLiteral([]))
+            ])), 
+            /*location*/ parameter), 1048576 /* CustomPrologue */));
+            // for (var _i = restIndex; _i < arguments.length; _i++) {
+            //   param[_i - restIndex] = arguments[_i];
+            // }
+            var forStatement = ts.createFor(ts.setTextRange(ts.createVariableDeclarationList([
+                ts.createVariableDeclaration(temp, /*type*/ undefined, ts.createLiteral(restIndex))
+            ]), parameter), ts.setTextRange(ts.createLessThan(temp, ts.createPropertyAccess(ts.createIdentifier("arguments"), "length")), parameter), ts.setTextRange(ts.createPostfixIncrement(temp), parameter), ts.createBlock([
+                ts.startOnNewLine(ts.setTextRange(ts.createStatement(ts.createAssignment(ts.createElementAccess(expressionName, restIndex === 0
+                    ? temp
+                    : ts.createSubtract(temp, ts.createLiteral(restIndex))), ts.createElementAccess(ts.createIdentifier("arguments"), temp))), 
+                /*location*/ parameter))
+            ]));
+            ts.setEmitFlags(forStatement, 1048576 /* CustomPrologue */);
+            ts.startOnNewLine(forStatement);
+            statements.push(forStatement);
+        }
+        /**
+         * Adds a statement to capture the `this` of a function declaration if it is needed.
+         *
+         * @param statements The statements for the new function body.
+         * @param node A node.
+         */
+        function addCaptureThisForNodeIfNeeded(statements, node) {
+            if (node.transformFlags & 32768 /* ContainsCapturedLexicalThis */ && node.kind !== 193 /* ArrowFunction */) {
+                captureThisForNode(statements, node, ts.createThis());
+            }
+        }
+        function captureThisForNode(statements, node, initializer, originalStatement) {
+            enableSubstitutionsForCapturedThis();
+            var captureThisStatement = ts.createVariableStatement(
+            /*modifiers*/ undefined, ts.createVariableDeclarationList([
+                ts.createVariableDeclaration(ts.createFileLevelUniqueName("_this"), 
+                /*type*/ undefined, initializer)
+            ]));
+            ts.setEmitFlags(captureThisStatement, 1536 /* NoComments */ | 1048576 /* CustomPrologue */);
+            ts.setTextRange(captureThisStatement, originalStatement);
+            ts.setSourceMapRange(captureThisStatement, node);
+            statements.push(captureThisStatement);
+        }
+        function prependCaptureNewTargetIfNeeded(statements, node, copyOnWrite) {
+            if (hierarchyFacts & 16384 /* NewTarget */) {
+                var newTarget = void 0;
+                switch (node.kind) {
+                    case 193 /* ArrowFunction */:
+                        return statements;
+                    case 154 /* MethodDeclaration */:
+                    case 156 /* GetAccessor */:
+                    case 157 /* SetAccessor */:
+                        // Methods and accessors cannot be constructors, so 'new.target' will
+                        // always return 'undefined'.
+                        newTarget = ts.createVoidZero();
+                        break;
+                    case 155 /* Constructor */:
+                        // Class constructors can only be called with `new`, so `this.constructor`
+                        // should be relatively safe to use.
+                        newTarget = ts.createPropertyAccess(ts.setEmitFlags(ts.createThis(), 4 /* NoSubstitution */), "constructor");
+                        break;
+                    case 234 /* FunctionDeclaration */:
+                    case 192 /* FunctionExpression */:
+                        // Functions can be called or constructed, and may have a `this` due to
+                        // being a member or when calling an imported function via `other_1.f()`.
+                        newTarget = ts.createConditional(ts.createLogicalAnd(ts.setEmitFlags(ts.createThis(), 4 /* NoSubstitution */), ts.createBinary(ts.setEmitFlags(ts.createThis(), 4 /* NoSubstitution */), 93 /* InstanceOfKeyword */, ts.getLocalName(node))), ts.createPropertyAccess(ts.setEmitFlags(ts.createThis(), 4 /* NoSubstitution */), "constructor"), ts.createVoidZero());
+                        break;
+                    default:
+                        return ts.Debug.failBadSyntaxKind(node);
+                }
+                var captureNewTargetStatement = ts.createVariableStatement(
+                /*modifiers*/ undefined, ts.createVariableDeclarationList([
+                    ts.createVariableDeclaration(ts.createFileLevelUniqueName("_newTarget"), 
+                    /*type*/ undefined, newTarget)
+                ]));
+                if (copyOnWrite) {
+                    return [captureNewTargetStatement].concat(statements);
+                }
+                statements.unshift(captureNewTargetStatement);
+            }
+            return statements;
+        }
+        /**
+         * Adds statements to the class body function for a class to define the members of the
+         * class.
+         *
+         * @param statements The statements for the class body function.
+         * @param node The ClassExpression or ClassDeclaration node.
+         */
+        function addClassMembers(statements, node) {
+            for (var _i = 0, _a = node.members; _i < _a.length; _i++) {
+                var member = _a[_i];
+                switch (member.kind) {
+                    case 212 /* SemicolonClassElement */:
+                        statements.push(transformSemicolonClassElementToStatement(member));
+                        break;
+                    case 154 /* MethodDeclaration */:
+                        statements.push(transformClassMethodDeclarationToStatement(getClassMemberPrefix(node, member), member, node));
+                        break;
+                    case 156 /* GetAccessor */:
+                    case 157 /* SetAccessor */:
+                        var accessors = ts.getAllAccessorDeclarations(node.members, member);
+                        if (member === accessors.firstAccessor) {
+                            statements.push(transformAccessorsToStatement(getClassMemberPrefix(node, member), accessors, node));
+                        }
+                        break;
+                    case 155 /* Constructor */:
+                        // Constructors are handled in visitClassExpression/visitClassDeclaration
+                        break;
+                    default:
+                        ts.Debug.failBadSyntaxKind(node);
+                        break;
+                }
+            }
+        }
+        /**
+         * Transforms a SemicolonClassElement into a statement for a class body function.
+         *
+         * @param member The SemicolonClassElement node.
+         */
+        function transformSemicolonClassElementToStatement(member) {
+            return ts.setTextRange(ts.createEmptyStatement(), member);
+        }
+        /**
+         * Transforms a MethodDeclaration into a statement for a class body function.
+         *
+         * @param receiver The receiver for the member.
+         * @param member The MethodDeclaration node.
+         */
+        function transformClassMethodDeclarationToStatement(receiver, member, container) {
+            var ancestorFacts = enterSubtree(0 /* None */, 0 /* None */);
+            var commentRange = ts.getCommentRange(member);
+            var sourceMapRange = ts.getSourceMapRange(member);
+            var memberName = ts.createMemberAccessForPropertyName(receiver, ts.visitNode(member.name, visitor, ts.isPropertyName), /*location*/ member.name);
+            var memberFunction = transformFunctionLikeToExpression(member, /*location*/ member, /*name*/ undefined, container);
+            ts.setEmitFlags(memberFunction, 1536 /* NoComments */);
+            ts.setSourceMapRange(memberFunction, sourceMapRange);
+            var statement = ts.setTextRange(ts.createStatement(ts.createAssignment(memberName, memberFunction)), 
+            /*location*/ member);
+            ts.setOriginalNode(statement, member);
+            ts.setCommentRange(statement, commentRange);
+            // The location for the statement is used to emit comments only.
+            // No source map should be emitted for this statement to align with the
+            // old emitter.
+            ts.setEmitFlags(statement, 48 /* NoSourceMap */);
+            exitSubtree(ancestorFacts, 49152 /* PropagateNewTargetMask */, hierarchyFacts & 49152 /* PropagateNewTargetMask */ ? 16384 /* NewTarget */ : 0 /* None */);
+            return statement;
+        }
+        /**
+         * Transforms a set of related of get/set accessors into a statement for a class body function.
+         *
+         * @param receiver The receiver for the member.
+         * @param accessors The set of related get/set accessors.
+         */
+        function transformAccessorsToStatement(receiver, accessors, container) {
+            var statement = ts.createStatement(transformAccessorsToExpression(receiver, accessors, container, /*startsOnNewLine*/ false));
+            // The location for the statement is used to emit source maps only.
+            // No comments should be emitted for this statement to align with the
+            // old emitter.
+            ts.setEmitFlags(statement, 1536 /* NoComments */);
+            ts.setSourceMapRange(statement, ts.getSourceMapRange(accessors.firstAccessor));
+            return statement;
+        }
+        /**
+         * Transforms a set of related get/set accessors into an expression for either a class
+         * body function or an ObjectLiteralExpression with computed properties.
+         *
+         * @param receiver The receiver for the member.
+         */
+        function transformAccessorsToExpression(receiver, _a, container, startsOnNewLine) {
+            var firstAccessor = _a.firstAccessor, getAccessor = _a.getAccessor, setAccessor = _a.setAccessor;
+            var ancestorFacts = enterSubtree(0 /* None */, 0 /* None */);
+            // To align with source maps in the old emitter, the receiver and property name
+            // arguments are both mapped contiguously to the accessor name.
+            var target = ts.getMutableClone(receiver);
+            ts.setEmitFlags(target, 1536 /* NoComments */ | 32 /* NoTrailingSourceMap */);
+            ts.setSourceMapRange(target, firstAccessor.name); // TODO: GH#18217
+            var propertyName = ts.createExpressionForPropertyName(ts.visitNode(firstAccessor.name, visitor, ts.isPropertyName));
+            ts.setEmitFlags(propertyName, 1536 /* NoComments */ | 16 /* NoLeadingSourceMap */);
+            ts.setSourceMapRange(propertyName, firstAccessor.name);
+            var properties = [];
+            if (getAccessor) {
+                var getterFunction = transformFunctionLikeToExpression(getAccessor, /*location*/ undefined, /*name*/ undefined, container);
+                ts.setSourceMapRange(getterFunction, ts.getSourceMapRange(getAccessor));
+                ts.setEmitFlags(getterFunction, 512 /* NoLeadingComments */);
+                var getter = ts.createPropertyAssignment("get", getterFunction);
+                ts.setCommentRange(getter, ts.getCommentRange(getAccessor));
+                properties.push(getter);
+            }
+            if (setAccessor) {
+                var setterFunction = transformFunctionLikeToExpression(setAccessor, /*location*/ undefined, /*name*/ undefined, container);
+                ts.setSourceMapRange(setterFunction, ts.getSourceMapRange(setAccessor));
+                ts.setEmitFlags(setterFunction, 512 /* NoLeadingComments */);
+                var setter = ts.createPropertyAssignment("set", setterFunction);
+                ts.setCommentRange(setter, ts.getCommentRange(setAccessor));
+                properties.push(setter);
+            }
+            properties.push(ts.createPropertyAssignment("enumerable", ts.createTrue()), ts.createPropertyAssignment("configurable", ts.createTrue()));
+            var call = ts.createCall(ts.createPropertyAccess(ts.createIdentifier("Object"), "defineProperty"), 
+            /*typeArguments*/ undefined, [
+                target,
+                propertyName,
+                ts.createObjectLiteral(properties, /*multiLine*/ true)
+            ]);
+            if (startsOnNewLine) {
+                ts.startOnNewLine(call);
+            }
+            exitSubtree(ancestorFacts, 49152 /* PropagateNewTargetMask */, hierarchyFacts & 49152 /* PropagateNewTargetMask */ ? 16384 /* NewTarget */ : 0 /* None */);
+            return call;
+        }
+        /**
+         * Visits an ArrowFunction and transforms it into a FunctionExpression.
+         *
+         * @param node An ArrowFunction node.
+         */
+        function visitArrowFunction(node) {
+            if (node.transformFlags & 16384 /* ContainsLexicalThis */) {
+                enableSubstitutionsForCapturedThis();
+            }
+            var savedConvertedLoopState = convertedLoopState;
+            convertedLoopState = undefined;
+            var ancestorFacts = enterSubtree(16256 /* ArrowFunctionExcludes */, 66 /* ArrowFunctionIncludes */);
+            var func = ts.createFunctionExpression(
+            /*modifiers*/ undefined, 
+            /*asteriskToken*/ undefined, 
+            /*name*/ undefined, 
+            /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+            /*type*/ undefined, transformFunctionBody(node));
+            ts.setTextRange(func, node);
+            ts.setOriginalNode(func, node);
+            ts.setEmitFlags(func, 8 /* CapturesThis */);
+            exitSubtree(ancestorFacts, 0 /* None */, 0 /* None */);
+            convertedLoopState = savedConvertedLoopState;
+            return func;
+        }
+        /**
+         * Visits a FunctionExpression node.
+         *
+         * @param node a FunctionExpression node.
+         */
+        function visitFunctionExpression(node) {
+            var ancestorFacts = ts.getEmitFlags(node) & 262144 /* AsyncFunctionBody */
+                ? enterSubtree(16278 /* AsyncFunctionBodyExcludes */, 69 /* AsyncFunctionBodyIncludes */)
+                : enterSubtree(16286 /* FunctionExcludes */, 65 /* FunctionIncludes */);
+            var savedConvertedLoopState = convertedLoopState;
+            convertedLoopState = undefined;
+            var parameters = ts.visitParameterList(node.parameters, visitor, context);
+            var body = node.transformFlags & 64 /* ES2015 */
+                ? transformFunctionBody(node)
+                : visitFunctionBodyDownLevel(node);
+            var name = hierarchyFacts & 16384 /* NewTarget */
+                ? ts.getLocalName(node)
+                : node.name;
+            exitSubtree(ancestorFacts, 49152 /* PropagateNewTargetMask */, 0 /* None */);
+            convertedLoopState = savedConvertedLoopState;
+            return ts.updateFunctionExpression(node, 
+            /*modifiers*/ undefined, node.asteriskToken, name, 
+            /*typeParameters*/ undefined, parameters, 
+            /*type*/ undefined, body);
+        }
+        /**
+         * Visits a FunctionDeclaration node.
+         *
+         * @param node a FunctionDeclaration node.
+         */
+        function visitFunctionDeclaration(node) {
+            var savedConvertedLoopState = convertedLoopState;
+            convertedLoopState = undefined;
+            var ancestorFacts = enterSubtree(16286 /* FunctionExcludes */, 65 /* FunctionIncludes */);
+            var parameters = ts.visitParameterList(node.parameters, visitor, context);
+            var body = node.transformFlags & 64 /* ES2015 */
+                ? transformFunctionBody(node)
+                : visitFunctionBodyDownLevel(node);
+            var name = hierarchyFacts & 16384 /* NewTarget */
+                ? ts.getLocalName(node)
+                : node.name;
+            exitSubtree(ancestorFacts, 49152 /* PropagateNewTargetMask */, 0 /* None */);
+            convertedLoopState = savedConvertedLoopState;
+            return ts.updateFunctionDeclaration(node, 
+            /*decorators*/ undefined, ts.visitNodes(node.modifiers, visitor, ts.isModifier), node.asteriskToken, name, 
+            /*typeParameters*/ undefined, parameters, 
+            /*type*/ undefined, body);
+        }
+        /**
+         * Transforms a function-like node into a FunctionExpression.
+         *
+         * @param node The function-like node to transform.
+         * @param location The source-map location for the new FunctionExpression.
+         * @param name The name of the new FunctionExpression.
+         */
+        function transformFunctionLikeToExpression(node, location, name, container) {
+            var savedConvertedLoopState = convertedLoopState;
+            convertedLoopState = undefined;
+            var ancestorFacts = container && ts.isClassLike(container) && !ts.hasModifier(node, 32 /* Static */)
+                ? enterSubtree(16286 /* FunctionExcludes */, 65 /* FunctionIncludes */ | 8 /* NonStaticClassElement */)
+                : enterSubtree(16286 /* FunctionExcludes */, 65 /* FunctionIncludes */);
+            var parameters = ts.visitParameterList(node.parameters, visitor, context);
+            var body = transformFunctionBody(node);
+            if (hierarchyFacts & 16384 /* NewTarget */ && !name && (node.kind === 234 /* FunctionDeclaration */ || node.kind === 192 /* FunctionExpression */)) {
+                name = ts.getGeneratedNameForNode(node);
+            }
+            exitSubtree(ancestorFacts, 49152 /* PropagateNewTargetMask */, 0 /* None */);
+            convertedLoopState = savedConvertedLoopState;
+            return ts.setOriginalNode(ts.setTextRange(ts.createFunctionExpression(
+            /*modifiers*/ undefined, node.asteriskToken, name, 
+            /*typeParameters*/ undefined, parameters, 
+            /*type*/ undefined, body), location), 
+            /*original*/ node);
+        }
+        /**
+         * Transforms the body of a function-like node.
+         *
+         * @param node A function-like node.
+         */
+        function transformFunctionBody(node) {
+            var multiLine = false; // indicates whether the block *must* be emitted as multiple lines
+            var singleLine = false; // indicates whether the block *may* be emitted as a single line
+            var statementsLocation;
+            var closeBraceLocation;
+            var leadingStatements = [];
+            var statements = [];
+            var body = node.body;
+            var statementOffset;
+            resumeLexicalEnvironment();
+            if (ts.isBlock(body)) {
+                // ensureUseStrict is false because no new prologue-directive should be added.
+                // addStandardPrologue will put already-existing directives at the beginning of the target statement-array
+                statementOffset = ts.addStandardPrologue(leadingStatements, body.statements, /*ensureUseStrict*/ false);
+            }
+            addCaptureThisForNodeIfNeeded(leadingStatements, node);
+            addDefaultValueAssignmentsIfNeeded(leadingStatements, node);
+            addRestParameterIfNeeded(leadingStatements, node, /*inConstructorWithSynthesizedSuper*/ false);
+            if (ts.isBlock(body)) {
+                // addCustomPrologue puts already-existing directives at the beginning of the target statement-array
+                statementOffset = ts.addCustomPrologue(leadingStatements, body.statements, statementOffset, visitor);
+                statementsLocation = body.statements;
+                ts.addRange(statements, ts.visitNodes(body.statements, visitor, ts.isStatement, statementOffset));
+                // If the original body was a multi-line block, this must be a multi-line block.
+                if (!multiLine && body.multiLine) {
+                    multiLine = true;
+                }
+            }
+            else {
+                ts.Debug.assert(node.kind === 193 /* ArrowFunction */);
+                // To align with the old emitter, we use a synthetic end position on the location
+                // for the statement list we synthesize when we down-level an arrow function with
+                // an expression function body. This prevents both comments and source maps from
+                // being emitted for the end position only.
+                statementsLocation = ts.moveRangeEnd(body, -1);
+                var equalsGreaterThanToken = node.equalsGreaterThanToken;
+                if (!ts.nodeIsSynthesized(equalsGreaterThanToken) && !ts.nodeIsSynthesized(body)) {
+                    if (ts.rangeEndIsOnSameLineAsRangeStart(equalsGreaterThanToken, body, currentSourceFile)) {
+                        singleLine = true;
+                    }
+                    else {
+                        multiLine = true;
+                    }
+                }
+                var expression = ts.visitNode(body, visitor, ts.isExpression);
+                var returnStatement = ts.createReturn(expression);
+                ts.setTextRange(returnStatement, body);
+                ts.moveSyntheticComments(returnStatement, body);
+                ts.setEmitFlags(returnStatement, 384 /* NoTokenSourceMaps */ | 32 /* NoTrailingSourceMap */ | 1024 /* NoTrailingComments */);
+                statements.push(returnStatement);
+                // To align with the source map emit for the old emitter, we set a custom
+                // source map location for the close brace.
+                closeBraceLocation = body;
+            }
+            var lexicalEnvironment = context.endLexicalEnvironment();
+            ts.prependStatements(statements, lexicalEnvironment);
+            prependCaptureNewTargetIfNeeded(statements, node, /*copyOnWrite*/ false);
+            // If we added any final generated statements, this must be a multi-line block
+            if (ts.some(leadingStatements) || ts.some(lexicalEnvironment)) {
+                multiLine = true;
+            }
+            var block = ts.createBlock(ts.setTextRange(ts.createNodeArray(leadingStatements.concat(statements)), statementsLocation), multiLine);
+            ts.setTextRange(block, node.body);
+            if (!multiLine && singleLine) {
+                ts.setEmitFlags(block, 1 /* SingleLine */);
+            }
+            if (closeBraceLocation) {
+                ts.setTokenSourceMapRange(block, 18 /* CloseBraceToken */, closeBraceLocation);
+            }
+            ts.setOriginalNode(block, node.body);
+            return block;
+        }
+        function visitFunctionBodyDownLevel(node) {
+            var updated = ts.visitFunctionBody(node.body, functionBodyVisitor, context);
+            return ts.updateBlock(updated, ts.setTextRange(ts.createNodeArray(prependCaptureNewTargetIfNeeded(updated.statements, node, /*copyOnWrite*/ true)), 
+            /*location*/ updated.statements));
+        }
+        function visitBlock(node, isFunctionBody) {
+            if (isFunctionBody) {
+                // A function body is not a block scope.
+                return ts.visitEachChild(node, visitor, context);
+            }
+            var ancestorFacts = hierarchyFacts & 256 /* IterationStatement */
+                ? enterSubtree(4032 /* IterationStatementBlockExcludes */, 512 /* IterationStatementBlockIncludes */)
+                : enterSubtree(3904 /* BlockExcludes */, 128 /* BlockIncludes */);
+            var updated = ts.visitEachChild(node, visitor, context);
+            exitSubtree(ancestorFacts, 0 /* None */, 0 /* None */);
+            return updated;
+        }
+        /**
+         * Visits an ExpressionStatement that contains a destructuring assignment.
+         *
+         * @param node An ExpressionStatement node.
+         */
+        function visitExpressionStatement(node) {
+            // If we are here it is most likely because our expression is a destructuring assignment.
+            switch (node.expression.kind) {
+                case 191 /* ParenthesizedExpression */:
+                    return ts.updateStatement(node, visitParenthesizedExpression(node.expression, /*needsDestructuringValue*/ false));
+                case 200 /* BinaryExpression */:
+                    return ts.updateStatement(node, visitBinaryExpression(node.expression, /*needsDestructuringValue*/ false));
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        /**
+         * Visits a ParenthesizedExpression that may contain a destructuring assignment.
+         *
+         * @param node A ParenthesizedExpression node.
+         * @param needsDestructuringValue A value indicating whether we need to hold onto the rhs
+         *                                of a destructuring assignment.
+         */
+        function visitParenthesizedExpression(node, needsDestructuringValue) {
+            // If we are here it is most likely because our expression is a destructuring assignment.
+            if (!needsDestructuringValue) {
+                // By default we always emit the RHS at the end of a flattened destructuring
+                // expression. If we are in a state where we do not need the destructuring value,
+                // we pass that information along to the children that care about it.
+                switch (node.expression.kind) {
+                    case 191 /* ParenthesizedExpression */:
+                        return ts.updateParen(node, visitParenthesizedExpression(node.expression, /*needsDestructuringValue*/ false));
+                    case 200 /* BinaryExpression */:
+                        return ts.updateParen(node, visitBinaryExpression(node.expression, /*needsDestructuringValue*/ false));
+                }
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        /**
+         * Visits a BinaryExpression that contains a destructuring assignment.
+         *
+         * @param node A BinaryExpression node.
+         * @param needsDestructuringValue A value indicating whether we need to hold onto the rhs
+         *                                of a destructuring assignment.
+         */
+        function visitBinaryExpression(node, needsDestructuringValue) {
+            // If we are here it is because this is a destructuring assignment.
+            if (ts.isDestructuringAssignment(node)) {
+                return ts.flattenDestructuringAssignment(node, visitor, context, 0 /* All */, needsDestructuringValue);
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitVariableStatement(node) {
+            var ancestorFacts = enterSubtree(0 /* None */, ts.hasModifier(node, 1 /* Export */) ? 32 /* ExportedVariableStatement */ : 0 /* None */);
+            var updated;
+            if (convertedLoopState && (node.declarationList.flags & 3 /* BlockScoped */) === 0) {
+                // we are inside a converted loop - hoist variable declarations
+                var assignments = void 0;
+                for (var _i = 0, _a = node.declarationList.declarations; _i < _a.length; _i++) {
+                    var decl = _a[_i];
+                    hoistVariableDeclarationDeclaredInConvertedLoop(convertedLoopState, decl);
+                    if (decl.initializer) {
+                        var assignment = void 0;
+                        if (ts.isBindingPattern(decl.name)) {
+                            assignment = ts.flattenDestructuringAssignment(decl, visitor, context, 0 /* All */);
+                        }
+                        else {
+                            assignment = ts.createBinary(decl.name, 58 /* EqualsToken */, ts.visitNode(decl.initializer, visitor, ts.isExpression));
+                            ts.setTextRange(assignment, decl);
+                        }
+                        assignments = ts.append(assignments, assignment);
+                    }
+                }
+                if (assignments) {
+                    updated = ts.setTextRange(ts.createStatement(ts.inlineExpressions(assignments)), node);
+                }
+                else {
+                    // none of declarations has initializer - the entire variable statement can be deleted
+                    updated = undefined;
+                }
+            }
+            else {
+                updated = ts.visitEachChild(node, visitor, context);
+            }
+            exitSubtree(ancestorFacts, 0 /* None */, 0 /* None */);
+            return updated;
+        }
+        /**
+         * Visits a VariableDeclarationList that is block scoped (e.g. `let` or `const`).
+         *
+         * @param node A VariableDeclarationList node.
+         */
+        function visitVariableDeclarationList(node) {
+            if (node.transformFlags & 64 /* ES2015 */) {
+                if (node.flags & 3 /* BlockScoped */) {
+                    enableSubstitutionsForBlockScopedBindings();
+                }
+                var declarations = ts.flatMap(node.declarations, node.flags & 1 /* Let */
+                    ? visitVariableDeclarationInLetDeclarationList
+                    : visitVariableDeclaration);
+                var declarationList = ts.createVariableDeclarationList(declarations);
+                ts.setOriginalNode(declarationList, node);
+                ts.setTextRange(declarationList, node);
+                ts.setCommentRange(declarationList, node);
+                if (node.transformFlags & 8388608 /* ContainsBindingPattern */
+                    && (ts.isBindingPattern(node.declarations[0].name) || ts.isBindingPattern(ts.last(node.declarations).name))) {
+                    // If the first or last declaration is a binding pattern, we need to modify
+                    // the source map range for the declaration list.
+                    var firstDeclaration = ts.firstOrUndefined(declarations);
+                    if (firstDeclaration) {
+                        ts.setSourceMapRange(declarationList, ts.createRange(firstDeclaration.pos, ts.last(declarations).end));
+                    }
+                }
+                return declarationList;
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        /**
+         * Gets a value indicating whether we should emit an explicit initializer for a variable
+         * declaration in a `let` declaration list.
+         *
+         * @param node A VariableDeclaration node.
+         */
+        function shouldEmitExplicitInitializerForLetDeclaration(node) {
+            // Nested let bindings might need to be initialized explicitly to preserve
+            // ES6 semantic:
+            //
+            //  { let x = 1; }
+            //  { let x; } // x here should be undefined. not 1
+            //
+            // Top level bindings never collide with anything and thus don't require
+            // explicit initialization. As for nested let bindings there are two cases:
+            //
+            // - Nested let bindings that were not renamed definitely should be
+            //   initialized explicitly:
+            //
+            //    { let x = 1; }
+            //    { let x; if (some-condition) { x = 1}; if (x) { /*1*/ } }
+            //
+            //   Without explicit initialization code in /*1*/ can be executed even if
+            //   some-condition is evaluated to false.
+            //
+            // - Renaming introduces fresh name that should not collide with any
+            //   existing names, however renamed bindings sometimes also should be
+            //   explicitly initialized. One particular case: non-captured binding
+            //   declared inside loop body (but not in loop initializer):
+            //
+            //    let x;
+            //    for (;;) {
+            //        let x;
+            //    }
+            //
+            //   In downlevel codegen inner 'x' will be renamed so it won't collide
+            //   with outer 'x' however it will should be reset on every iteration as
+            //   if it was declared anew.
+            //
+            //   * Why non-captured binding?
+            //     - Because if loop contains block scoped binding captured in some
+            //       function then loop body will be rewritten to have a fresh scope
+            //       on every iteration so everything will just work.
+            //
+            //   * Why loop initializer is excluded?
+            //     - Since we've introduced a fresh name it already will be undefined.
+            var flags = resolver.getNodeCheckFlags(node);
+            var isCapturedInFunction = flags & 131072 /* CapturedBlockScopedBinding */;
+            var isDeclaredInLoop = flags & 262144 /* BlockScopedBindingInLoop */;
+            var emittedAsTopLevel = (hierarchyFacts & 64 /* TopLevel */) !== 0
+                || (isCapturedInFunction
+                    && isDeclaredInLoop
+                    && (hierarchyFacts & 512 /* IterationStatementBlock */) !== 0);
+            var emitExplicitInitializer = !emittedAsTopLevel
+                && (hierarchyFacts & 2048 /* ForInOrForOfStatement */) === 0
+                && (!resolver.isDeclarationWithCollidingName(node)
+                    || (isDeclaredInLoop
+                        && !isCapturedInFunction
+                        && (hierarchyFacts & (1024 /* ForStatement */ | 2048 /* ForInOrForOfStatement */)) === 0));
+            return emitExplicitInitializer;
+        }
+        /**
+         * Visits a VariableDeclaration in a `let` declaration list.
+         *
+         * @param node A VariableDeclaration node.
+         */
+        function visitVariableDeclarationInLetDeclarationList(node) {
+            // For binding pattern names that lack initializers there is no point to emit
+            // explicit initializer since downlevel codegen for destructuring will fail
+            // in the absence of initializer so all binding elements will say uninitialized
+            var name = node.name;
+            if (ts.isBindingPattern(name)) {
+                return visitVariableDeclaration(node);
+            }
+            if (!node.initializer && shouldEmitExplicitInitializerForLetDeclaration(node)) {
+                var clone_2 = ts.getMutableClone(node);
+                clone_2.initializer = ts.createVoidZero();
+                return clone_2;
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        /**
+         * Visits a VariableDeclaration node with a binding pattern.
+         *
+         * @param node A VariableDeclaration node.
+         */
+        function visitVariableDeclaration(node) {
+            var ancestorFacts = enterSubtree(32 /* ExportedVariableStatement */, 0 /* None */);
+            var updated;
+            if (ts.isBindingPattern(node.name)) {
+                updated = ts.flattenDestructuringBinding(node, visitor, context, 0 /* All */, 
+                /*value*/ undefined, (ancestorFacts & 32 /* ExportedVariableStatement */) !== 0);
+            }
+            else {
+                updated = ts.visitEachChild(node, visitor, context);
+            }
+            exitSubtree(ancestorFacts, 0 /* None */, 0 /* None */);
+            return updated;
+        }
+        function recordLabel(node) {
+            convertedLoopState.labels.set(ts.idText(node.label), true);
+        }
+        function resetLabel(node) {
+            convertedLoopState.labels.set(ts.idText(node.label), false);
+        }
+        function visitLabeledStatement(node) {
+            if (convertedLoopState && !convertedLoopState.labels) {
+                convertedLoopState.labels = ts.createMap();
+            }
+            var statement = ts.unwrapInnermostStatementOfLabel(node, convertedLoopState && recordLabel);
+            return ts.isIterationStatement(statement, /*lookInLabeledStatements*/ false)
+                ? visitIterationStatement(statement, /*outermostLabeledStatement*/ node)
+                : ts.restoreEnclosingLabel(ts.visitNode(statement, visitor, ts.isStatement), node, convertedLoopState && resetLabel);
+        }
+        function visitIterationStatement(node, outermostLabeledStatement) {
+            switch (node.kind) {
+                case 218 /* DoStatement */:
+                case 219 /* WhileStatement */:
+                    return visitDoOrWhileStatement(node, outermostLabeledStatement);
+                case 220 /* ForStatement */:
+                    return visitForStatement(node, outermostLabeledStatement);
+                case 221 /* ForInStatement */:
+                    return visitForInStatement(node, outermostLabeledStatement);
+                case 222 /* ForOfStatement */:
+                    return visitForOfStatement(node, outermostLabeledStatement);
+            }
+        }
+        function visitIterationStatementWithFacts(excludeFacts, includeFacts, node, outermostLabeledStatement, convert) {
+            var ancestorFacts = enterSubtree(excludeFacts, includeFacts);
+            var updated = convertIterationStatementBodyIfNecessary(node, outermostLabeledStatement, convert);
+            exitSubtree(ancestorFacts, 0 /* None */, 0 /* None */);
+            return updated;
+        }
+        function visitDoOrWhileStatement(node, outermostLabeledStatement) {
+            return visitIterationStatementWithFacts(0 /* DoOrWhileStatementExcludes */, 256 /* DoOrWhileStatementIncludes */, node, outermostLabeledStatement);
+        }
+        function visitForStatement(node, outermostLabeledStatement) {
+            return visitIterationStatementWithFacts(3008 /* ForStatementExcludes */, 1280 /* ForStatementIncludes */, node, outermostLabeledStatement);
+        }
+        function visitForInStatement(node, outermostLabeledStatement) {
+            return visitIterationStatementWithFacts(1984 /* ForInOrForOfStatementExcludes */, 2304 /* ForInOrForOfStatementIncludes */, node, outermostLabeledStatement);
+        }
+        function visitForOfStatement(node, outermostLabeledStatement) {
+            return visitIterationStatementWithFacts(1984 /* ForInOrForOfStatementExcludes */, 2304 /* ForInOrForOfStatementIncludes */, node, outermostLabeledStatement, compilerOptions.downlevelIteration ? convertForOfStatementForIterable : convertForOfStatementForArray);
+        }
+        function convertForOfStatementHead(node, boundValue, convertedLoopBodyStatements) {
+            var statements = [];
+            var initializer = node.initializer;
+            if (ts.isVariableDeclarationList(initializer)) {
+                if (node.initializer.flags & 3 /* BlockScoped */) {
+                    enableSubstitutionsForBlockScopedBindings();
+                }
+                var firstOriginalDeclaration = ts.firstOrUndefined(initializer.declarations);
+                if (firstOriginalDeclaration && ts.isBindingPattern(firstOriginalDeclaration.name)) {
+                    // This works whether the declaration is a var, let, or const.
+                    // It will use rhsIterationValue _a[_i] as the initializer.
+                    var declarations = ts.flattenDestructuringBinding(firstOriginalDeclaration, visitor, context, 0 /* All */, boundValue);
+                    var declarationList = ts.setTextRange(ts.createVariableDeclarationList(declarations), node.initializer);
+                    ts.setOriginalNode(declarationList, node.initializer);
+                    // Adjust the source map range for the first declaration to align with the old
+                    // emitter.
+                    ts.setSourceMapRange(declarationList, ts.createRange(declarations[0].pos, ts.last(declarations).end));
+                    statements.push(ts.createVariableStatement(
+                    /*modifiers*/ undefined, declarationList));
+                }
+                else {
+                    // The following call does not include the initializer, so we have
+                    // to emit it separately.
+                    statements.push(ts.setTextRange(ts.createVariableStatement(
+                    /*modifiers*/ undefined, ts.setOriginalNode(ts.setTextRange(ts.createVariableDeclarationList([
+                        ts.createVariableDeclaration(firstOriginalDeclaration ? firstOriginalDeclaration.name : ts.createTempVariable(/*recordTempVariable*/ undefined), 
+                        /*type*/ undefined, boundValue)
+                    ]), ts.moveRangePos(initializer, -1)), initializer)), ts.moveRangeEnd(initializer, -1)));
+                }
+            }
+            else {
+                // Initializer is an expression. Emit the expression in the body, so that it's
+                // evaluated on every iteration.
+                var assignment = ts.createAssignment(initializer, boundValue);
+                if (ts.isDestructuringAssignment(assignment)) {
+                    ts.aggregateTransformFlags(assignment);
+                    statements.push(ts.createStatement(visitBinaryExpression(assignment, /*needsDestructuringValue*/ false)));
+                }
+                else {
+                    assignment.end = initializer.end;
+                    statements.push(ts.setTextRange(ts.createStatement(ts.visitNode(assignment, visitor, ts.isExpression)), ts.moveRangeEnd(initializer, -1)));
+                }
+            }
+            if (convertedLoopBodyStatements) {
+                return createSyntheticBlockForConvertedStatements(ts.addRange(statements, convertedLoopBodyStatements));
+            }
+            else {
+                var statement = ts.visitNode(node.statement, visitor, ts.isStatement, ts.liftToBlock);
+                if (ts.isBlock(statement)) {
+                    return ts.updateBlock(statement, ts.setTextRange(ts.createNodeArray(ts.concatenate(statements, statement.statements)), statement.statements));
+                }
+                else {
+                    statements.push(statement);
+                    return createSyntheticBlockForConvertedStatements(statements);
+                }
+            }
+        }
+        function createSyntheticBlockForConvertedStatements(statements) {
+            return ts.setEmitFlags(ts.createBlock(ts.createNodeArray(statements), 
+            /*multiLine*/ true), 48 /* NoSourceMap */ | 384 /* NoTokenSourceMaps */);
+        }
+        function convertForOfStatementForArray(node, outermostLabeledStatement, convertedLoopBodyStatements) {
+            // The following ES6 code:
+            //
+            //    for (let v of expr) { }
+            //
+            // should be emitted as
+            //
+            //    for (var _i = 0, _a = expr; _i < _a.length; _i++) {
+            //        var v = _a[_i];
+            //    }
+            //
+            // where _a and _i are temps emitted to capture the RHS and the counter,
+            // respectively.
+            // When the left hand side is an expression instead of a let declaration,
+            // the "let v" is not emitted.
+            // When the left hand side is a let/const, the v is renamed if there is
+            // another v in scope.
+            // Note that all assignments to the LHS are emitted in the body, including
+            // all destructuring.
+            // Note also that because an extra statement is needed to assign to the LHS,
+            // for-of bodies are always emitted as blocks.
+            var expression = ts.visitNode(node.expression, visitor, ts.isExpression);
+            // In the case where the user wrote an identifier as the RHS, like this:
+            //
+            //     for (let v of arr) { }
+            //
+            // we don't want to emit a temporary variable for the RHS, just use it directly.
+            var counter = ts.createLoopVariable();
+            var rhsReference = ts.isIdentifier(expression) ? ts.getGeneratedNameForNode(expression) : ts.createTempVariable(/*recordTempVariable*/ undefined);
+            // The old emitter does not emit source maps for the expression
+            ts.setEmitFlags(expression, 48 /* NoSourceMap */ | ts.getEmitFlags(expression));
+            var forStatement = ts.setTextRange(ts.createFor(
+            /*initializer*/ ts.setEmitFlags(ts.setTextRange(ts.createVariableDeclarationList([
+                ts.setTextRange(ts.createVariableDeclaration(counter, /*type*/ undefined, ts.createLiteral(0)), ts.moveRangePos(node.expression, -1)),
+                ts.setTextRange(ts.createVariableDeclaration(rhsReference, /*type*/ undefined, expression), node.expression)
+            ]), node.expression), 2097152 /* NoHoisting */), 
+            /*condition*/ ts.setTextRange(ts.createLessThan(counter, ts.createPropertyAccess(rhsReference, "length")), node.expression), 
+            /*incrementor*/ ts.setTextRange(ts.createPostfixIncrement(counter), node.expression), 
+            /*statement*/ convertForOfStatementHead(node, ts.createElementAccess(rhsReference, counter), convertedLoopBodyStatements)), 
+            /*location*/ node);
+            // Disable trailing source maps for the OpenParenToken to align source map emit with the old emitter.
+            ts.setEmitFlags(forStatement, 256 /* NoTokenTrailingSourceMaps */);
+            ts.setTextRange(forStatement, node);
+            return ts.restoreEnclosingLabel(forStatement, outermostLabeledStatement, convertedLoopState && resetLabel);
+        }
+        function convertForOfStatementForIterable(node, outermostLabeledStatement, convertedLoopBodyStatements) {
+            var expression = ts.visitNode(node.expression, visitor, ts.isExpression);
+            var iterator = ts.isIdentifier(expression) ? ts.getGeneratedNameForNode(expression) : ts.createTempVariable(/*recordTempVariable*/ undefined);
+            var result = ts.isIdentifier(expression) ? ts.getGeneratedNameForNode(iterator) : ts.createTempVariable(/*recordTempVariable*/ undefined);
+            var errorRecord = ts.createUniqueName("e");
+            var catchVariable = ts.getGeneratedNameForNode(errorRecord);
+            var returnMethod = ts.createTempVariable(/*recordTempVariable*/ undefined);
+            var values = ts.createValuesHelper(context, expression, node.expression);
+            var next = ts.createCall(ts.createPropertyAccess(iterator, "next"), /*typeArguments*/ undefined, []);
+            hoistVariableDeclaration(errorRecord);
+            hoistVariableDeclaration(returnMethod);
+            var forStatement = ts.setEmitFlags(ts.setTextRange(ts.createFor(
+            /*initializer*/ ts.setEmitFlags(ts.setTextRange(ts.createVariableDeclarationList([
+                ts.setTextRange(ts.createVariableDeclaration(iterator, /*type*/ undefined, values), node.expression),
+                ts.createVariableDeclaration(result, /*type*/ undefined, next)
+            ]), node.expression), 2097152 /* NoHoisting */), 
+            /*condition*/ ts.createLogicalNot(ts.createPropertyAccess(result, "done")), 
+            /*incrementor*/ ts.createAssignment(result, next), 
+            /*statement*/ convertForOfStatementHead(node, ts.createPropertyAccess(result, "value"), convertedLoopBodyStatements)), 
+            /*location*/ node), 256 /* NoTokenTrailingSourceMaps */);
+            return ts.createTry(ts.createBlock([
+                ts.restoreEnclosingLabel(forStatement, outermostLabeledStatement, convertedLoopState && resetLabel)
+            ]), ts.createCatchClause(ts.createVariableDeclaration(catchVariable), ts.setEmitFlags(ts.createBlock([
+                ts.createStatement(ts.createAssignment(errorRecord, ts.createObjectLiteral([
+                    ts.createPropertyAssignment("error", catchVariable)
+                ])))
+            ]), 1 /* SingleLine */)), ts.createBlock([
+                ts.createTry(
+                /*tryBlock*/ ts.createBlock([
+                    ts.setEmitFlags(ts.createIf(ts.createLogicalAnd(ts.createLogicalAnd(result, ts.createLogicalNot(ts.createPropertyAccess(result, "done"))), ts.createAssignment(returnMethod, ts.createPropertyAccess(iterator, "return"))), ts.createStatement(ts.createFunctionCall(returnMethod, iterator, []))), 1 /* SingleLine */),
+                ]), 
+                /*catchClause*/ undefined, 
+                /*finallyBlock*/ ts.setEmitFlags(ts.createBlock([
+                    ts.setEmitFlags(ts.createIf(errorRecord, ts.createThrow(ts.createPropertyAccess(errorRecord, "error"))), 1 /* SingleLine */)
+                ]), 1 /* SingleLine */))
+            ]));
+        }
+        /**
+         * Visits an ObjectLiteralExpression with computed property names.
+         *
+         * @param node An ObjectLiteralExpression node.
+         */
+        function visitObjectLiteralExpression(node) {
+            // We are here because a ComputedPropertyName was used somewhere in the expression.
+            var properties = node.properties;
+            var numProperties = properties.length;
+            // Find the first computed property.
+            // Everything until that point can be emitted as part of the initial object literal.
+            var numInitialProperties = numProperties;
+            var numInitialPropertiesWithoutYield = numProperties;
+            for (var i = 0; i < numProperties; i++) {
+                var property = properties[i];
+                if ((property.transformFlags & 16777216 /* ContainsYield */ && hierarchyFacts & 4 /* AsyncFunctionBody */)
+                    && i < numInitialPropertiesWithoutYield) {
+                    numInitialPropertiesWithoutYield = i;
+                }
+                if (property.name.kind === 147 /* ComputedPropertyName */) {
+                    numInitialProperties = i;
+                    break;
+                }
+            }
+            if (numInitialProperties !== numProperties) {
+                if (numInitialPropertiesWithoutYield < numInitialProperties) {
+                    numInitialProperties = numInitialPropertiesWithoutYield;
+                }
+                // For computed properties, we need to create a unique handle to the object
+                // literal so we can modify it without risking internal assignments tainting the object.
+                var temp = ts.createTempVariable(hoistVariableDeclaration);
+                // Write out the first non-computed properties, then emit the rest through indexing on the temp variable.
+                var expressions = [];
+                var assignment = ts.createAssignment(temp, ts.setEmitFlags(ts.createObjectLiteral(ts.visitNodes(properties, visitor, ts.isObjectLiteralElementLike, 0, numInitialProperties), node.multiLine), 65536 /* Indented */));
+                if (node.multiLine) {
+                    ts.startOnNewLine(assignment);
+                }
+                expressions.push(assignment);
+                addObjectLiteralMembers(expressions, node, temp, numInitialProperties);
+                // We need to clone the temporary identifier so that we can write it on a
+                // new line
+                expressions.push(node.multiLine ? ts.startOnNewLine(ts.getMutableClone(temp)) : temp);
+                return ts.inlineExpressions(expressions);
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function shouldConvertIterationStatementBody(node) {
+            return (resolver.getNodeCheckFlags(node) & 65536 /* LoopWithCapturedBlockScopedBinding */) !== 0;
+        }
+        /**
+         * Records constituents of name for the given variable to be hoisted in the outer scope.
+         */
+        function hoistVariableDeclarationDeclaredInConvertedLoop(state, node) {
+            if (!state.hoistedLocalVariables) {
+                state.hoistedLocalVariables = [];
+            }
+            visit(node.name);
+            function visit(node) {
+                if (node.kind === 71 /* Identifier */) {
+                    state.hoistedLocalVariables.push(node);
+                }
+                else {
+                    for (var _i = 0, _a = node.elements; _i < _a.length; _i++) {
+                        var element = _a[_i];
+                        if (!ts.isOmittedExpression(element)) {
+                            visit(element.name);
+                        }
+                    }
+                }
+            }
+        }
+        function convertIterationStatementBodyIfNecessary(node, outermostLabeledStatement, convert) {
+            if (!shouldConvertIterationStatementBody(node)) {
+                var saveAllowedNonLabeledJumps = void 0;
+                if (convertedLoopState) {
+                    // we get here if we are trying to emit normal loop loop inside converted loop
+                    // set allowedNonLabeledJumps to Break | Continue to mark that break\continue inside the loop should be emitted as is
+                    saveAllowedNonLabeledJumps = convertedLoopState.allowedNonLabeledJumps;
+                    convertedLoopState.allowedNonLabeledJumps = 2 /* Break */ | 4 /* Continue */;
+                }
+                var result = convert
+                    ? convert(node, outermostLabeledStatement, /*convertedLoopBodyStatements*/ undefined)
+                    : ts.restoreEnclosingLabel(ts.visitEachChild(node, visitor, context), outermostLabeledStatement, convertedLoopState && resetLabel);
+                if (convertedLoopState) {
+                    convertedLoopState.allowedNonLabeledJumps = saveAllowedNonLabeledJumps;
+                }
+                return result;
+            }
+            var functionName = ts.createUniqueName("_loop");
+            var loopInitializer;
+            switch (node.kind) {
+                case 220 /* ForStatement */:
+                case 221 /* ForInStatement */:
+                case 222 /* ForOfStatement */:
+                    var initializer = node.initializer;
+                    if (initializer && initializer.kind === 233 /* VariableDeclarationList */) {
+                        loopInitializer = initializer;
+                    }
+                    break;
+            }
+            // variables that will be passed to the loop as parameters
+            var loopParameters = [];
+            // variables declared in the loop initializer that will be changed inside the loop
+            var loopOutParameters = [];
+            if (loopInitializer && (ts.getCombinedNodeFlags(loopInitializer) & 3 /* BlockScoped */)) {
+                for (var _i = 0, _a = loopInitializer.declarations; _i < _a.length; _i++) {
+                    var decl = _a[_i];
+                    processLoopVariableDeclaration(decl, loopParameters, loopOutParameters);
+                }
+            }
+            var outerConvertedLoopState = convertedLoopState;
+            convertedLoopState = { loopOutParameters: loopOutParameters };
+            if (outerConvertedLoopState) {
+                // convertedOuterLoopState !== undefined means that this converted loop is nested in another converted loop.
+                // if outer converted loop has already accumulated some state - pass it through
+                if (outerConvertedLoopState.argumentsName) {
+                    // outer loop has already used 'arguments' so we've already have some name to alias it
+                    // use the same name in all nested loops
+                    convertedLoopState.argumentsName = outerConvertedLoopState.argumentsName;
+                }
+                if (outerConvertedLoopState.thisName) {
+                    // outer loop has already used 'this' so we've already have some name to alias it
+                    // use the same name in all nested loops
+                    convertedLoopState.thisName = outerConvertedLoopState.thisName;
+                }
+                if (outerConvertedLoopState.hoistedLocalVariables) {
+                    // we've already collected some non-block scoped variable declarations in enclosing loop
+                    // use the same storage in nested loop
+                    convertedLoopState.hoistedLocalVariables = outerConvertedLoopState.hoistedLocalVariables;
+                }
+            }
+            startLexicalEnvironment();
+            var loopBody = ts.visitNode(node.statement, visitor, ts.isStatement, ts.liftToBlock);
+            var lexicalEnvironment = endLexicalEnvironment();
+            var currentState = convertedLoopState;
+            convertedLoopState = outerConvertedLoopState;
+            if (loopOutParameters.length || lexicalEnvironment) {
+                var statements_4 = ts.isBlock(loopBody) ? loopBody.statements.slice() : [loopBody];
+                if (loopOutParameters.length) {
+                    copyOutParameters(loopOutParameters, 1 /* ToOutParameter */, statements_4);
+                }
+                ts.prependStatements(statements_4, lexicalEnvironment);
+                loopBody = ts.createBlock(statements_4, /*multiline*/ true);
+            }
+            if (ts.isBlock(loopBody)) {
+                loopBody.multiLine = true;
+            }
+            else {
+                loopBody = ts.createBlock([loopBody], /*multiline*/ true);
+            }
+            var containsYield = (node.statement.transformFlags & 16777216 /* ContainsYield */) !== 0;
+            var isAsyncBlockContainingAwait = containsYield && (hierarchyFacts & 4 /* AsyncFunctionBody */) !== 0;
+            var loopBodyFlags = 0;
+            if (currentState.containsLexicalThis) {
+                loopBodyFlags |= 8 /* CapturesThis */;
+            }
+            if (isAsyncBlockContainingAwait) {
+                loopBodyFlags |= 262144 /* AsyncFunctionBody */;
+            }
+            var convertedLoopVariable = ts.createVariableStatement(
+            /*modifiers*/ undefined, ts.setEmitFlags(ts.createVariableDeclarationList([
+                ts.createVariableDeclaration(functionName, 
+                /*type*/ undefined, ts.setEmitFlags(ts.createFunctionExpression(
+                /*modifiers*/ undefined, containsYield ? ts.createToken(39 /* AsteriskToken */) : undefined, 
+                /*name*/ undefined, 
+                /*typeParameters*/ undefined, loopParameters, 
+                /*type*/ undefined, loopBody), loopBodyFlags))
+            ]), 2097152 /* NoHoisting */));
+            var statements = [convertedLoopVariable];
+            var extraVariableDeclarations;
+            // propagate state from the inner loop to the outer loop if necessary
+            if (currentState.argumentsName) {
+                // if alias for arguments is set
+                if (outerConvertedLoopState) {
+                    // pass it to outer converted loop
+                    outerConvertedLoopState.argumentsName = currentState.argumentsName;
+                }
+                else {
+                    // this is top level converted loop and we need to create an alias for 'arguments' object
+                    (extraVariableDeclarations || (extraVariableDeclarations = [])).push(ts.createVariableDeclaration(currentState.argumentsName, 
+                    /*type*/ undefined, ts.createIdentifier("arguments")));
+                }
+            }
+            if (currentState.thisName) {
+                // if alias for this is set
+                if (outerConvertedLoopState) {
+                    // pass it to outer converted loop
+                    outerConvertedLoopState.thisName = currentState.thisName;
+                }
+                else {
+                    // this is top level converted loop so we need to create an alias for 'this' here
+                    // NOTE:
+                    // if converted loops were all nested in arrow function then we'll always emit '_this' so convertedLoopState.thisName will not be set.
+                    // If it is set this means that all nested loops are not nested in arrow function and it is safe to capture 'this'.
+                    (extraVariableDeclarations || (extraVariableDeclarations = [])).push(ts.createVariableDeclaration(currentState.thisName, 
+                    /*type*/ undefined, ts.createIdentifier("this")));
+                }
+            }
+            if (currentState.hoistedLocalVariables) {
+                // if hoistedLocalVariables !== undefined this means that we've possibly collected some variable declarations to be hoisted later
+                if (outerConvertedLoopState) {
+                    // pass them to outer converted loop
+                    outerConvertedLoopState.hoistedLocalVariables = currentState.hoistedLocalVariables;
+                }
+                else {
+                    if (!extraVariableDeclarations) {
+                        extraVariableDeclarations = [];
+                    }
+                    // hoist collected variable declarations
+                    for (var _b = 0, _c = currentState.hoistedLocalVariables; _b < _c.length; _b++) {
+                        var identifier = _c[_b];
+                        extraVariableDeclarations.push(ts.createVariableDeclaration(identifier));
+                    }
+                }
+            }
+            // add extra variables to hold out parameters if necessary
+            if (loopOutParameters.length) {
+                if (!extraVariableDeclarations) {
+                    extraVariableDeclarations = [];
+                }
+                for (var _d = 0, loopOutParameters_1 = loopOutParameters; _d < loopOutParameters_1.length; _d++) {
+                    var outParam = loopOutParameters_1[_d];
+                    extraVariableDeclarations.push(ts.createVariableDeclaration(outParam.outParamName));
+                }
+            }
+            // create variable statement to hold all introduced variable declarations
+            if (extraVariableDeclarations) {
+                statements.push(ts.createVariableStatement(
+                /*modifiers*/ undefined, ts.createVariableDeclarationList(extraVariableDeclarations)));
+            }
+            var convertedLoopBodyStatements = generateCallToConvertedLoop(functionName, loopParameters, currentState, containsYield);
+            var loop;
+            if (convert) {
+                loop = convert(node, outermostLabeledStatement, convertedLoopBodyStatements);
+            }
+            else {
+                var clone_3 = ts.getMutableClone(node);
+                // clean statement part
+                clone_3.statement = undefined;
+                // visit childnodes to transform initializer/condition/incrementor parts
+                clone_3 = ts.visitEachChild(clone_3, visitor, context);
+                // set loop statement
+                clone_3.statement = ts.createBlock(convertedLoopBodyStatements, /*multiline*/ true);
+                // reset and re-aggregate the transform flags
+                clone_3.transformFlags = 0;
+                ts.aggregateTransformFlags(clone_3);
+                loop = ts.restoreEnclosingLabel(clone_3, outermostLabeledStatement, convertedLoopState && resetLabel);
+            }
+            statements.push(loop);
+            return statements;
+        }
+        function copyOutParameter(outParam, copyDirection) {
+            var source = copyDirection === 0 /* ToOriginal */ ? outParam.outParamName : outParam.originalName;
+            var target = copyDirection === 0 /* ToOriginal */ ? outParam.originalName : outParam.outParamName;
+            return ts.createBinary(target, 58 /* EqualsToken */, source);
+        }
+        function copyOutParameters(outParams, copyDirection, statements) {
+            for (var _i = 0, outParams_1 = outParams; _i < outParams_1.length; _i++) {
+                var outParam = outParams_1[_i];
+                statements.push(ts.createStatement(copyOutParameter(outParam, copyDirection)));
+            }
+        }
+        function generateCallToConvertedLoop(loopFunctionExpressionName, parameters, state, isAsyncBlockContainingAwait) {
+            var outerConvertedLoopState = convertedLoopState;
+            var statements = [];
+            // loop is considered simple if it does not have any return statements or break\continue that transfer control outside of the loop
+            // simple loops are emitted as just 'loop()';
+            // NOTE: if loop uses only 'continue' it still will be emitted as simple loop
+            var isSimpleLoop = !(state.nonLocalJumps & ~4 /* Continue */) &&
+                !state.labeledNonLocalBreaks &&
+                !state.labeledNonLocalContinues;
+            var call = ts.createCall(loopFunctionExpressionName, /*typeArguments*/ undefined, ts.map(parameters, function (p) { return p.name; }));
+            var callResult = isAsyncBlockContainingAwait
+                ? ts.createYield(ts.createToken(39 /* AsteriskToken */), ts.setEmitFlags(call, 8388608 /* Iterator */))
+                : call;
+            if (isSimpleLoop) {
+                statements.push(ts.createStatement(callResult));
+                copyOutParameters(state.loopOutParameters, 0 /* ToOriginal */, statements);
+            }
+            else {
+                var loopResultName = ts.createUniqueName("state");
+                var stateVariable = ts.createVariableStatement(
+                /*modifiers*/ undefined, ts.createVariableDeclarationList([ts.createVariableDeclaration(loopResultName, /*type*/ undefined, callResult)]));
+                statements.push(stateVariable);
+                copyOutParameters(state.loopOutParameters, 0 /* ToOriginal */, statements);
+                if (state.nonLocalJumps & 8 /* Return */) {
+                    var returnStatement = void 0;
+                    if (outerConvertedLoopState) {
+                        outerConvertedLoopState.nonLocalJumps |= 8 /* Return */;
+                        returnStatement = ts.createReturn(loopResultName);
+                    }
+                    else {
+                        returnStatement = ts.createReturn(ts.createPropertyAccess(loopResultName, "value"));
+                    }
+                    statements.push(ts.createIf(ts.createBinary(ts.createTypeOf(loopResultName), 34 /* EqualsEqualsEqualsToken */, ts.createLiteral("object")), returnStatement));
+                }
+                if (state.nonLocalJumps & 2 /* Break */) {
+                    statements.push(ts.createIf(ts.createBinary(loopResultName, 34 /* EqualsEqualsEqualsToken */, ts.createLiteral("break")), ts.createBreak()));
+                }
+                if (state.labeledNonLocalBreaks || state.labeledNonLocalContinues) {
+                    var caseClauses = [];
+                    processLabeledJumps(state.labeledNonLocalBreaks, /*isBreak*/ true, loopResultName, outerConvertedLoopState, caseClauses);
+                    processLabeledJumps(state.labeledNonLocalContinues, /*isBreak*/ false, loopResultName, outerConvertedLoopState, caseClauses);
+                    statements.push(ts.createSwitch(loopResultName, ts.createCaseBlock(caseClauses)));
+                }
+            }
+            return statements;
+        }
+        function setLabeledJump(state, isBreak, labelText, labelMarker) {
+            if (isBreak) {
+                if (!state.labeledNonLocalBreaks) {
+                    state.labeledNonLocalBreaks = ts.createMap();
+                }
+                state.labeledNonLocalBreaks.set(labelText, labelMarker);
+            }
+            else {
+                if (!state.labeledNonLocalContinues) {
+                    state.labeledNonLocalContinues = ts.createMap();
+                }
+                state.labeledNonLocalContinues.set(labelText, labelMarker);
+            }
+        }
+        function processLabeledJumps(table, isBreak, loopResultName, outerLoop, caseClauses) {
+            if (!table) {
+                return;
+            }
+            table.forEach(function (labelMarker, labelText) {
+                var statements = [];
+                // if there are no outer converted loop or outer label in question is located inside outer converted loop
+                // then emit labeled break\continue
+                // otherwise propagate pair 'label -> marker' to outer converted loop and emit 'return labelMarker' so outer loop can later decide what to do
+                if (!outerLoop || (outerLoop.labels && outerLoop.labels.get(labelText))) {
+                    var label = ts.createIdentifier(labelText);
+                    statements.push(isBreak ? ts.createBreak(label) : ts.createContinue(label));
+                }
+                else {
+                    setLabeledJump(outerLoop, isBreak, labelText, labelMarker);
+                    statements.push(ts.createReturn(loopResultName));
+                }
+                caseClauses.push(ts.createCaseClause(ts.createLiteral(labelMarker), statements));
+            });
+        }
+        function processLoopVariableDeclaration(decl, loopParameters, loopOutParameters) {
+            var name = decl.name;
+            if (ts.isBindingPattern(name)) {
+                for (var _i = 0, _a = name.elements; _i < _a.length; _i++) {
+                    var element = _a[_i];
+                    if (!ts.isOmittedExpression(element)) {
+                        processLoopVariableDeclaration(element, loopParameters, loopOutParameters);
+                    }
+                }
+            }
+            else {
+                loopParameters.push(ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, name));
+                if (resolver.getNodeCheckFlags(decl) & 2097152 /* NeedsLoopOutParameter */) {
+                    var outParamName = ts.createUniqueName("out_" + ts.idText(name));
+                    loopOutParameters.push({ originalName: name, outParamName: outParamName });
+                }
+            }
+        }
+        /**
+         * Adds the members of an object literal to an array of expressions.
+         *
+         * @param expressions An array of expressions.
+         * @param node An ObjectLiteralExpression node.
+         * @param receiver The receiver for members of the ObjectLiteralExpression.
+         * @param numInitialNonComputedProperties The number of initial properties without
+         *                                        computed property names.
+         */
+        function addObjectLiteralMembers(expressions, node, receiver, start) {
+            var properties = node.properties;
+            var numProperties = properties.length;
+            for (var i = start; i < numProperties; i++) {
+                var property = properties[i];
+                switch (property.kind) {
+                    case 156 /* GetAccessor */:
+                    case 157 /* SetAccessor */:
+                        var accessors = ts.getAllAccessorDeclarations(node.properties, property);
+                        if (property === accessors.firstAccessor) {
+                            expressions.push(transformAccessorsToExpression(receiver, accessors, node, !!node.multiLine));
+                        }
+                        break;
+                    case 154 /* MethodDeclaration */:
+                        expressions.push(transformObjectLiteralMethodDeclarationToExpression(property, receiver, node, node.multiLine));
+                        break;
+                    case 270 /* PropertyAssignment */:
+                        expressions.push(transformPropertyAssignmentToExpression(property, receiver, node.multiLine));
+                        break;
+                    case 271 /* ShorthandPropertyAssignment */:
+                        expressions.push(transformShorthandPropertyAssignmentToExpression(property, receiver, node.multiLine));
+                        break;
+                    default:
+                        ts.Debug.failBadSyntaxKind(node);
+                        break;
+                }
+            }
+        }
+        /**
+         * Transforms a PropertyAssignment node into an expression.
+         *
+         * @param node The ObjectLiteralExpression that contains the PropertyAssignment.
+         * @param property The PropertyAssignment node.
+         * @param receiver The receiver for the assignment.
+         */
+        function transformPropertyAssignmentToExpression(property, receiver, startsOnNewLine) {
+            var expression = ts.createAssignment(ts.createMemberAccessForPropertyName(receiver, ts.visitNode(property.name, visitor, ts.isPropertyName)), ts.visitNode(property.initializer, visitor, ts.isExpression));
+            ts.setTextRange(expression, property);
+            if (startsOnNewLine) {
+                ts.startOnNewLine(expression);
+            }
+            return expression;
+        }
+        /**
+         * Transforms a ShorthandPropertyAssignment node into an expression.
+         *
+         * @param node The ObjectLiteralExpression that contains the ShorthandPropertyAssignment.
+         * @param property The ShorthandPropertyAssignment node.
+         * @param receiver The receiver for the assignment.
+         */
+        function transformShorthandPropertyAssignmentToExpression(property, receiver, startsOnNewLine) {
+            var expression = ts.createAssignment(ts.createMemberAccessForPropertyName(receiver, ts.visitNode(property.name, visitor, ts.isPropertyName)), ts.getSynthesizedClone(property.name));
+            ts.setTextRange(expression, property);
+            if (startsOnNewLine) {
+                ts.startOnNewLine(expression);
+            }
+            return expression;
+        }
+        /**
+         * Transforms a MethodDeclaration of an ObjectLiteralExpression into an expression.
+         *
+         * @param node The ObjectLiteralExpression that contains the MethodDeclaration.
+         * @param method The MethodDeclaration node.
+         * @param receiver The receiver for the assignment.
+         */
+        function transformObjectLiteralMethodDeclarationToExpression(method, receiver, container, startsOnNewLine) {
+            var ancestorFacts = enterSubtree(0 /* None */, 0 /* None */);
+            var expression = ts.createAssignment(ts.createMemberAccessForPropertyName(receiver, ts.visitNode(method.name, visitor, ts.isPropertyName)), transformFunctionLikeToExpression(method, /*location*/ method, /*name*/ undefined, container));
+            ts.setTextRange(expression, method);
+            if (startsOnNewLine) {
+                ts.startOnNewLine(expression);
+            }
+            exitSubtree(ancestorFacts, 49152 /* PropagateNewTargetMask */, hierarchyFacts & 49152 /* PropagateNewTargetMask */ ? 16384 /* NewTarget */ : 0 /* None */);
+            return expression;
+        }
+        function visitCatchClause(node) {
+            var ancestorFacts = enterSubtree(4032 /* BlockScopeExcludes */, 0 /* BlockScopeIncludes */);
+            var updated;
+            ts.Debug.assert(!!node.variableDeclaration, "Catch clause variable should always be present when downleveling ES2015.");
+            if (ts.isBindingPattern(node.variableDeclaration.name)) {
+                var temp = ts.createTempVariable(/*recordTempVariable*/ undefined);
+                var newVariableDeclaration = ts.createVariableDeclaration(temp);
+                ts.setTextRange(newVariableDeclaration, node.variableDeclaration);
+                var vars = ts.flattenDestructuringBinding(node.variableDeclaration, visitor, context, 0 /* All */, temp);
+                var list = ts.createVariableDeclarationList(vars);
+                ts.setTextRange(list, node.variableDeclaration);
+                var destructure = ts.createVariableStatement(/*modifiers*/ undefined, list);
+                updated = ts.updateCatchClause(node, newVariableDeclaration, addStatementToStartOfBlock(node.block, destructure));
+            }
+            else {
+                updated = ts.visitEachChild(node, visitor, context);
+            }
+            exitSubtree(ancestorFacts, 0 /* None */, 0 /* None */);
+            return updated;
+        }
+        function addStatementToStartOfBlock(block, statement) {
+            var transformedStatements = ts.visitNodes(block.statements, visitor, ts.isStatement);
+            return ts.updateBlock(block, [statement].concat(transformedStatements));
+        }
+        /**
+         * Visits a MethodDeclaration of an ObjectLiteralExpression and transforms it into a
+         * PropertyAssignment.
+         *
+         * @param node A MethodDeclaration node.
+         */
+        function visitMethodDeclaration(node) {
+            // We should only get here for methods on an object literal with regular identifier names.
+            // Methods on classes are handled in visitClassDeclaration/visitClassExpression.
+            // Methods with computed property names are handled in visitObjectLiteralExpression.
+            ts.Debug.assert(!ts.isComputedPropertyName(node.name));
+            var functionExpression = transformFunctionLikeToExpression(node, /*location*/ ts.moveRangePos(node, -1), /*name*/ undefined, /*container*/ undefined);
+            ts.setEmitFlags(functionExpression, 512 /* NoLeadingComments */ | ts.getEmitFlags(functionExpression));
+            return ts.setTextRange(ts.createPropertyAssignment(node.name, functionExpression), 
+            /*location*/ node);
+        }
+        /**
+         * Visits an AccessorDeclaration of an ObjectLiteralExpression.
+         *
+         * @param node An AccessorDeclaration node.
+         */
+        function visitAccessorDeclaration(node) {
+            ts.Debug.assert(!ts.isComputedPropertyName(node.name));
+            var savedConvertedLoopState = convertedLoopState;
+            convertedLoopState = undefined;
+            var ancestorFacts = enterSubtree(16286 /* FunctionExcludes */, 65 /* FunctionIncludes */);
+            var updated;
+            var parameters = ts.visitParameterList(node.parameters, visitor, context);
+            var body = node.transformFlags & (32768 /* ContainsCapturedLexicalThis */ | 128 /* ContainsES2015 */)
+                ? transformFunctionBody(node)
+                : visitFunctionBodyDownLevel(node);
+            if (node.kind === 156 /* GetAccessor */) {
+                updated = ts.updateGetAccessor(node, node.decorators, node.modifiers, node.name, parameters, node.type, body);
+            }
+            else {
+                updated = ts.updateSetAccessor(node, node.decorators, node.modifiers, node.name, parameters, body);
+            }
+            exitSubtree(ancestorFacts, 49152 /* PropagateNewTargetMask */, 0 /* None */);
+            convertedLoopState = savedConvertedLoopState;
+            return updated;
+        }
+        /**
+         * Visits a ShorthandPropertyAssignment and transforms it into a PropertyAssignment.
+         *
+         * @param node A ShorthandPropertyAssignment node.
+         */
+        function visitShorthandPropertyAssignment(node) {
+            return ts.setTextRange(ts.createPropertyAssignment(node.name, ts.getSynthesizedClone(node.name)), 
+            /*location*/ node);
+        }
+        function visitComputedPropertyName(node) {
+            var ancestorFacts = enterSubtree(0 /* ComputedPropertyNameExcludes */, 8192 /* ComputedPropertyNameIncludes */);
+            var updated = ts.visitEachChild(node, visitor, context);
+            exitSubtree(ancestorFacts, 49152 /* PropagateNewTargetMask */, hierarchyFacts & 49152 /* PropagateNewTargetMask */ ? 32768 /* NewTargetInComputedPropertyName */ : 0 /* None */);
+            return updated;
+        }
+        /**
+         * Visits a YieldExpression node.
+         *
+         * @param node A YieldExpression node.
+         */
+        function visitYieldExpression(node) {
+            // `yield` expressions are transformed using the generators transformer.
+            return ts.visitEachChild(node, visitor, context);
+        }
+        /**
+         * Visits an ArrayLiteralExpression that contains a spread element.
+         *
+         * @param node An ArrayLiteralExpression node.
+         */
+        function visitArrayLiteralExpression(node) {
+            if (node.transformFlags & 64 /* ES2015 */) {
+                // We are here because we contain a SpreadElementExpression.
+                return transformAndSpreadElements(node.elements, /*needsUniqueCopy*/ true, !!node.multiLine, /*hasTrailingComma*/ !!node.elements.hasTrailingComma);
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        /**
+         * Visits a CallExpression that contains either a spread element or `super`.
+         *
+         * @param node a CallExpression.
+         */
+        function visitCallExpression(node) {
+            if (ts.getEmitFlags(node) & 33554432 /* TypeScriptClassWrapper */) {
+                return visitTypeScriptClassWrapper(node);
+            }
+            if (node.transformFlags & 64 /* ES2015 */) {
+                return visitCallExpressionWithPotentialCapturedThisAssignment(node, /*assignToCapturedThis*/ true);
+            }
+            return ts.updateCall(node, ts.visitNode(node.expression, callExpressionVisitor, ts.isExpression), 
+            /*typeArguments*/ undefined, ts.visitNodes(node.arguments, visitor, ts.isExpression));
+        }
+        function visitTypeScriptClassWrapper(node) {
+            // This is a call to a class wrapper function (an IIFE) created by the 'ts' transformer.
+            // The wrapper has a form similar to:
+            //
+            //  (function() {
+            //      class C { // 1
+            //      }
+            //      C.x = 1; // 2
+            //      return C;
+            //  }())
+            //
+            // When we transform the class, we end up with something like this:
+            //
+            //  (function () {
+            //      var C = (function () { // 3
+            //          function C() {
+            //          }
+            //          return C; // 4
+            //      }());
+            //      C.x = 1;
+            //      return C;
+            //  }())
+            //
+            // We want to simplify the two nested IIFEs to end up with something like this:
+            //
+            //  (function () {
+            //      function C() {
+            //      }
+            //      C.x = 1;
+            //      return C;
+            //  }())
+            // We skip any outer expressions in a number of places to get to the innermost
+            // expression, but we will restore them later to preserve comments and source maps.
+            var body = ts.cast(ts.cast(ts.skipOuterExpressions(node.expression), ts.isArrowFunction).body, ts.isBlock);
+            // The class statements are the statements generated by visiting the first statement with initializer of the
+            // body (1), while all other statements are added to remainingStatements (2)
+            var isVariableStatementWithInitializer = function (stmt) { return ts.isVariableStatement(stmt) && !!ts.first(stmt.declarationList.declarations).initializer; };
+            var bodyStatements = ts.visitNodes(body.statements, visitor, ts.isStatement);
+            var classStatements = ts.filter(bodyStatements, isVariableStatementWithInitializer);
+            var remainingStatements = ts.filter(bodyStatements, function (stmt) { return !isVariableStatementWithInitializer(stmt); });
+            var varStatement = ts.cast(ts.first(classStatements), ts.isVariableStatement);
+            // We know there is only one variable declaration here as we verified this in an
+            // earlier call to isTypeScriptClassWrapper
+            var variable = varStatement.declarationList.declarations[0];
+            var initializer = ts.skipOuterExpressions(variable.initializer);
+            // Under certain conditions, the 'ts' transformer may introduce a class alias, which
+            // we see as an assignment, for example:
+            //
+            //  (function () {
+            //      var C_1;
+            //      var C = C_1 = (function () {
+            //          function C() {
+            //          }
+            //          C.x = function () { return C_1; }
+            //          return C;
+            //      }());
+            //      C = C_1 = __decorate([dec], C);
+            //      return C;
+            //  }())
+            //
+            var aliasAssignment = ts.tryCast(initializer, ts.isAssignmentExpression);
+            // The underlying call (3) is another IIFE that may contain a '_super' argument.
+            var call = ts.cast(aliasAssignment ? ts.skipOuterExpressions(aliasAssignment.right) : initializer, ts.isCallExpression);
+            var func = ts.cast(ts.skipOuterExpressions(call.expression), ts.isFunctionExpression);
+            var funcStatements = func.body.statements;
+            var classBodyStart = 0;
+            var classBodyEnd = -1;
+            var statements = [];
+            if (aliasAssignment) {
+                // If we have a class alias assignment, we need to move it to the down-level constructor
+                // function we generated for the class.
+                var extendsCall = ts.tryCast(funcStatements[classBodyStart], ts.isExpressionStatement);
+                if (extendsCall) {
+                    statements.push(extendsCall);
+                    classBodyStart++;
+                }
+                // The next statement is the function declaration.
+                statements.push(funcStatements[classBodyStart]);
+                classBodyStart++;
+                // Add the class alias following the declaration.
+                statements.push(ts.createStatement(ts.createAssignment(aliasAssignment.left, ts.cast(variable.name, ts.isIdentifier))));
+            }
+            // Find the trailing 'return' statement (4)
+            while (!ts.isReturnStatement(ts.elementAt(funcStatements, classBodyEnd))) {
+                classBodyEnd--;
+            }
+            // When we extract the statements of the inner IIFE, we exclude the 'return' statement (4)
+            // as we already have one that has been introduced by the 'ts' transformer.
+            ts.addRange(statements, funcStatements, classBodyStart, classBodyEnd);
+            if (classBodyEnd < -1) {
+                // If there were any hoisted declarations following the return statement, we should
+                // append them.
+                ts.addRange(statements, funcStatements, classBodyEnd + 1);
+            }
+            // Add the remaining statements of the outer wrapper.
+            ts.addRange(statements, remainingStatements);
+            // The 'es2015' class transform may add an end-of-declaration marker. If so we will add it
+            // after the remaining statements from the 'ts' transformer.
+            ts.addRange(statements, classStatements, /*start*/ 1);
+            // Recreate any outer parentheses or partially-emitted expressions to preserve source map
+            // and comment locations.
+            return ts.recreateOuterExpressions(node.expression, ts.recreateOuterExpressions(variable.initializer, ts.recreateOuterExpressions(aliasAssignment && aliasAssignment.right, ts.updateCall(call, ts.recreateOuterExpressions(call.expression, ts.updateFunctionExpression(func, 
+            /*modifiers*/ undefined, 
+            /*asteriskToken*/ undefined, 
+            /*name*/ undefined, 
+            /*typeParameters*/ undefined, func.parameters, 
+            /*type*/ undefined, ts.updateBlock(func.body, statements))), 
+            /*typeArguments*/ undefined, call.arguments))));
+        }
+        function visitImmediateSuperCallInBody(node) {
+            return visitCallExpressionWithPotentialCapturedThisAssignment(node, /*assignToCapturedThis*/ false);
+        }
+        function visitCallExpressionWithPotentialCapturedThisAssignment(node, assignToCapturedThis) {
+            // We are here either because SuperKeyword was used somewhere in the expression, or
+            // because we contain a SpreadElementExpression.
+            if (node.transformFlags & 524288 /* ContainsSpread */ ||
+                node.expression.kind === 97 /* SuperKeyword */ ||
+                ts.isSuperProperty(ts.skipOuterExpressions(node.expression))) {
+                var _a = ts.createCallBinding(node.expression, hoistVariableDeclaration), target = _a.target, thisArg = _a.thisArg;
+                if (node.expression.kind === 97 /* SuperKeyword */) {
+                    ts.setEmitFlags(thisArg, 4 /* NoSubstitution */);
+                }
+                var resultingCall = void 0;
+                if (node.transformFlags & 524288 /* ContainsSpread */) {
+                    // [source]
+                    //      f(...a, b)
+                    //      x.m(...a, b)
+                    //      super(...a, b)
+                    //      super.m(...a, b) // in static
+                    //      super.m(...a, b) // in instance
+                    //
+                    // [output]
+                    //      f.apply(void 0, a.concat([b]))
+                    //      (_a = x).m.apply(_a, a.concat([b]))
+                    //      _super.apply(this, a.concat([b]))
+                    //      _super.m.apply(this, a.concat([b]))
+                    //      _super.prototype.m.apply(this, a.concat([b]))
+                    resultingCall = ts.createFunctionApply(ts.visitNode(target, callExpressionVisitor, ts.isExpression), ts.visitNode(thisArg, visitor, ts.isExpression), transformAndSpreadElements(node.arguments, /*needsUniqueCopy*/ false, /*multiLine*/ false, /*hasTrailingComma*/ false));
+                }
+                else {
+                    // [source]
+                    //      super(a)
+                    //      super.m(a) // in static
+                    //      super.m(a) // in instance
+                    //
+                    // [output]
+                    //      _super.call(this, a)
+                    //      _super.m.call(this, a)
+                    //      _super.prototype.m.call(this, a)
+                    resultingCall = ts.createFunctionCall(ts.visitNode(target, callExpressionVisitor, ts.isExpression), ts.visitNode(thisArg, visitor, ts.isExpression), ts.visitNodes(node.arguments, visitor, ts.isExpression), 
+                    /*location*/ node);
+                }
+                if (node.expression.kind === 97 /* SuperKeyword */) {
+                    var actualThis = ts.createThis();
+                    ts.setEmitFlags(actualThis, 4 /* NoSubstitution */);
+                    var initializer = ts.createLogicalOr(resultingCall, actualThis);
+                    resultingCall = assignToCapturedThis
+                        ? ts.createAssignment(ts.createFileLevelUniqueName("_this"), initializer)
+                        : initializer;
+                }
+                return ts.setOriginalNode(resultingCall, node);
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        /**
+         * Visits a NewExpression that contains a spread element.
+         *
+         * @param node A NewExpression node.
+         */
+        function visitNewExpression(node) {
+            if (node.transformFlags & 524288 /* ContainsSpread */) {
+                // We are here because we contain a SpreadElementExpression.
+                // [source]
+                //      new C(...a)
+                //
+                // [output]
+                //      new ((_a = C).bind.apply(_a, [void 0].concat(a)))()
+                var _a = ts.createCallBinding(ts.createPropertyAccess(node.expression, "bind"), hoistVariableDeclaration), target = _a.target, thisArg = _a.thisArg;
+                return ts.createNew(ts.createFunctionApply(ts.visitNode(target, visitor, ts.isExpression), thisArg, transformAndSpreadElements(ts.createNodeArray([ts.createVoidZero()].concat(node.arguments)), /*needsUniqueCopy*/ false, /*multiLine*/ false, /*hasTrailingComma*/ false)), 
+                /*typeArguments*/ undefined, []);
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        /**
+         * Transforms an array of Expression nodes that contains a SpreadExpression.
+         *
+         * @param elements The array of Expression nodes.
+         * @param needsUniqueCopy A value indicating whether to ensure that the result is a fresh array.
+         * @param multiLine A value indicating whether the result should be emitted on multiple lines.
+         */
+        function transformAndSpreadElements(elements, needsUniqueCopy, multiLine, hasTrailingComma) {
+            // [source]
+            //      [a, ...b, c]
+            //
+            // [output]
+            //      [a].concat(b, [c])
+            // Map spans of spread expressions into their expressions and spans of other
+            // expressions into an array literal.
+            var numElements = elements.length;
+            var segments = ts.flatten(ts.spanMap(elements, partitionSpread, function (partition, visitPartition, _start, end) {
+                return visitPartition(partition, multiLine, hasTrailingComma && end === numElements);
+            }));
+            if (compilerOptions.downlevelIteration) {
+                if (segments.length === 1) {
+                    var firstSegment = segments[0];
+                    if (ts.isCallExpression(firstSegment)
+                        && ts.isIdentifier(firstSegment.expression)
+                        && (ts.getEmitFlags(firstSegment.expression) & 4096 /* HelperName */)
+                        && firstSegment.expression.escapedText === "___spread") {
+                        return segments[0];
+                    }
+                }
+                return ts.createSpreadHelper(context, segments);
+            }
+            else {
+                if (segments.length === 1) {
+                    var firstElement = elements[0];
+                    return needsUniqueCopy && ts.isSpreadElement(firstElement) && firstElement.expression.kind !== 183 /* ArrayLiteralExpression */
+                        ? ts.createArraySlice(segments[0])
+                        : segments[0];
+                }
+                // Rewrite using the pattern <segment0>.concat(<segment1>, <segment2>, ...)
+                return ts.createArrayConcat(segments.shift(), segments);
+            }
+        }
+        function partitionSpread(node) {
+            return ts.isSpreadElement(node)
+                ? visitSpanOfSpreads
+                : visitSpanOfNonSpreads;
+        }
+        function visitSpanOfSpreads(chunk) {
+            return ts.map(chunk, visitExpressionOfSpread);
+        }
+        function visitSpanOfNonSpreads(chunk, multiLine, hasTrailingComma) {
+            return ts.createArrayLiteral(ts.visitNodes(ts.createNodeArray(chunk, hasTrailingComma), visitor, ts.isExpression), multiLine);
+        }
+        function visitSpreadElement(node) {
+            return ts.visitNode(node.expression, visitor, ts.isExpression);
+        }
+        /**
+         * Transforms the expression of a SpreadExpression node.
+         *
+         * @param node A SpreadExpression node.
+         */
+        function visitExpressionOfSpread(node) {
+            return ts.visitNode(node.expression, visitor, ts.isExpression);
+        }
+        /**
+         * Visits a template literal.
+         *
+         * @param node A template literal.
+         */
+        function visitTemplateLiteral(node) {
+            return ts.setTextRange(ts.createLiteral(node.text), node);
+        }
+        /**
+         * Visits a string literal with an extended unicode escape.
+         *
+         * @param node A string literal.
+         */
+        function visitStringLiteral(node) {
+            if (node.hasExtendedUnicodeEscape) {
+                return ts.setTextRange(ts.createLiteral(node.text), node);
+            }
+            return node;
+        }
+        /**
+         * Visits a binary or octal (ES6) numeric literal.
+         *
+         * @param node A string literal.
+         */
+        function visitNumericLiteral(node) {
+            if (node.numericLiteralFlags & 384 /* BinaryOrOctalSpecifier */) {
+                return ts.setTextRange(ts.createNumericLiteral(node.text), node);
+            }
+            return node;
+        }
+        /**
+         * Visits a TaggedTemplateExpression node.
+         *
+         * @param node A TaggedTemplateExpression node.
+         */
+        function visitTaggedTemplateExpression(node) {
+            // Visit the tag expression
+            var tag = ts.visitNode(node.tag, visitor, ts.isExpression);
+            // Build up the template arguments and the raw and cooked strings for the template.
+            // We start out with 'undefined' for the first argument and revisit later
+            // to avoid walking over the template string twice and shifting all our arguments over after the fact.
+            var templateArguments = [undefined];
+            var cookedStrings = [];
+            var rawStrings = [];
+            var template = node.template;
+            if (ts.isNoSubstitutionTemplateLiteral(template)) {
+                cookedStrings.push(ts.createLiteral(template.text));
+                rawStrings.push(getRawLiteral(template));
+            }
+            else {
+                cookedStrings.push(ts.createLiteral(template.head.text));
+                rawStrings.push(getRawLiteral(template.head));
+                for (var _i = 0, _a = template.templateSpans; _i < _a.length; _i++) {
+                    var templateSpan = _a[_i];
+                    cookedStrings.push(ts.createLiteral(templateSpan.literal.text));
+                    rawStrings.push(getRawLiteral(templateSpan.literal));
+                    templateArguments.push(ts.visitNode(templateSpan.expression, visitor, ts.isExpression));
+                }
+            }
+            var helperCall = createTemplateObjectHelper(context, ts.createArrayLiteral(cookedStrings), ts.createArrayLiteral(rawStrings));
+            // Create a variable to cache the template object if we're in a module.
+            // Do not do this in the global scope, as any variable we currently generate could conflict with
+            // variables from outside of the current compilation. In the future, we can revisit this behavior.
+            if (ts.isExternalModule(currentSourceFile)) {
+                var tempVar = ts.createUniqueName("templateObject");
+                recordTaggedTemplateString(tempVar);
+                templateArguments[0] = ts.createLogicalOr(tempVar, ts.createAssignment(tempVar, helperCall));
+            }
+            else {
+                templateArguments[0] = helperCall;
+            }
+            return ts.createCall(tag, /*typeArguments*/ undefined, templateArguments);
+        }
+        /**
+         * Creates an ES5 compatible literal from an ES6 template literal.
+         *
+         * @param node The ES6 template literal.
+         */
+        function getRawLiteral(node) {
+            // Find original source text, since we need to emit the raw strings of the tagged template.
+            // The raw strings contain the (escaped) strings of what the user wrote.
+            // Examples: `\n` is converted to "\\n", a template string with a newline to "\n".
+            var text = ts.getSourceTextOfNodeFromSourceFile(currentSourceFile, node);
+            // text contains the original source, it will also contain quotes ("`"), dolar signs and braces ("${" and "}"),
+            // thus we need to remove those characters.
+            // First template piece starts with "`", others with "}"
+            // Last template piece ends with "`", others with "${"
+            var isLast = node.kind === 13 /* NoSubstitutionTemplateLiteral */ || node.kind === 16 /* TemplateTail */;
+            text = text.substring(1, text.length - (isLast ? 1 : 2));
+            // Newline normalization:
+            // ES6 Spec 11.8.6.1 - Static Semantics of TV's and TRV's
+            // <CR><LF> and <CR> LineTerminatorSequences are normalized to <LF> for both TV and TRV.
+            text = text.replace(/\r\n?/g, "\n");
+            return ts.setTextRange(ts.createLiteral(text), node);
+        }
+        /**
+         * Visits a TemplateExpression node.
+         *
+         * @param node A TemplateExpression node.
+         */
+        function visitTemplateExpression(node) {
+            var expressions = [];
+            addTemplateHead(expressions, node);
+            addTemplateSpans(expressions, node);
+            // createAdd will check if each expression binds less closely than binary '+'.
+            // If it does, it wraps the expression in parentheses. Otherwise, something like
+            //    `abc${ 1 << 2 }`
+            // becomes
+            //    "abc" + 1 << 2 + ""
+            // which is really
+            //    ("abc" + 1) << (2 + "")
+            // rather than
+            //    "abc" + (1 << 2) + ""
+            var expression = ts.reduceLeft(expressions, ts.createAdd);
+            if (ts.nodeIsSynthesized(expression)) {
+                expression.pos = node.pos;
+                expression.end = node.end;
+            }
+            return expression;
+        }
+        /**
+         * Gets a value indicating whether we need to include the head of a TemplateExpression.
+         *
+         * @param node A TemplateExpression node.
+         */
+        function shouldAddTemplateHead(node) {
+            // If this expression has an empty head literal and the first template span has a non-empty
+            // literal, then emitting the empty head literal is not necessary.
+            //     `${ foo } and ${ bar }`
+            // can be emitted as
+            //     foo + " and " + bar
+            // This is because it is only required that one of the first two operands in the emit
+            // output must be a string literal, so that the other operand and all following operands
+            // are forced into strings.
+            //
+            // If the first template span has an empty literal, then the head must still be emitted.
+            //     `${ foo }${ bar }`
+            // must still be emitted as
+            //     "" + foo + bar
+            // There is always atleast one templateSpan in this code path, since
+            // NoSubstitutionTemplateLiterals are directly emitted via emitLiteral()
+            ts.Debug.assert(node.templateSpans.length !== 0);
+            return node.head.text.length !== 0 || node.templateSpans[0].literal.text.length === 0;
+        }
+        /**
+         * Adds the head of a TemplateExpression to an array of expressions.
+         *
+         * @param expressions An array of expressions.
+         * @param node A TemplateExpression node.
+         */
+        function addTemplateHead(expressions, node) {
+            if (!shouldAddTemplateHead(node)) {
+                return;
+            }
+            expressions.push(ts.createLiteral(node.head.text));
+        }
+        /**
+         * Visits and adds the template spans of a TemplateExpression to an array of expressions.
+         *
+         * @param expressions An array of expressions.
+         * @param node A TemplateExpression node.
+         */
+        function addTemplateSpans(expressions, node) {
+            for (var _i = 0, _a = node.templateSpans; _i < _a.length; _i++) {
+                var span = _a[_i];
+                expressions.push(ts.visitNode(span.expression, visitor, ts.isExpression));
+                // Only emit if the literal is non-empty.
+                // The binary '+' operator is left-associative, so the first string concatenation
+                // with the head will force the result up to this point to be a string.
+                // Emitting a '+ ""' has no semantic effect for middles and tails.
+                if (span.literal.text.length !== 0) {
+                    expressions.push(ts.createLiteral(span.literal.text));
+                }
+            }
+        }
+        /**
+         * Visits the `super` keyword
+         */
+        function visitSuperKeyword(isExpressionOfCall) {
+            return hierarchyFacts & 8 /* NonStaticClassElement */
+                && !isExpressionOfCall
+                ? ts.createPropertyAccess(ts.createFileLevelUniqueName("_super"), "prototype")
+                : ts.createFileLevelUniqueName("_super");
+        }
+        function visitMetaProperty(node) {
+            if (node.keywordToken === 94 /* NewKeyword */ && node.name.escapedText === "target") {
+                if (hierarchyFacts & 8192 /* ComputedPropertyName */) {
+                    hierarchyFacts |= 32768 /* NewTargetInComputedPropertyName */;
+                }
+                else {
+                    hierarchyFacts |= 16384 /* NewTarget */;
+                }
+                return ts.createFileLevelUniqueName("_newTarget");
+            }
+            return node;
+        }
+        /**
+         * Called by the printer just before a node is printed.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to be printed.
+         * @param emitCallback The callback used to emit the node.
+         */
+        function onEmitNode(hint, node, emitCallback) {
+            if (enabledSubstitutions & 1 /* CapturedThis */ && ts.isFunctionLike(node)) {
+                // If we are tracking a captured `this`, keep track of the enclosing function.
+                var ancestorFacts = enterSubtree(16286 /* FunctionExcludes */, ts.getEmitFlags(node) & 8 /* CapturesThis */
+                    ? 65 /* FunctionIncludes */ | 16 /* CapturesThis */
+                    : 65 /* FunctionIncludes */);
+                previousOnEmitNode(hint, node, emitCallback);
+                exitSubtree(ancestorFacts, 0 /* None */, 0 /* None */);
+                return;
+            }
+            previousOnEmitNode(hint, node, emitCallback);
+        }
+        /**
+         * Enables a more costly code path for substitutions when we determine a source file
+         * contains block-scoped bindings (e.g. `let` or `const`).
+         */
+        function enableSubstitutionsForBlockScopedBindings() {
+            if ((enabledSubstitutions & 2 /* BlockScopedBindings */) === 0) {
+                enabledSubstitutions |= 2 /* BlockScopedBindings */;
+                context.enableSubstitution(71 /* Identifier */);
+            }
+        }
+        /**
+         * Enables a more costly code path for substitutions when we determine a source file
+         * contains a captured `this`.
+         */
+        function enableSubstitutionsForCapturedThis() {
+            if ((enabledSubstitutions & 1 /* CapturedThis */) === 0) {
+                enabledSubstitutions |= 1 /* CapturedThis */;
+                context.enableSubstitution(99 /* ThisKeyword */);
+                context.enableEmitNotification(155 /* Constructor */);
+                context.enableEmitNotification(154 /* MethodDeclaration */);
+                context.enableEmitNotification(156 /* GetAccessor */);
+                context.enableEmitNotification(157 /* SetAccessor */);
+                context.enableEmitNotification(193 /* ArrowFunction */);
+                context.enableEmitNotification(192 /* FunctionExpression */);
+                context.enableEmitNotification(234 /* FunctionDeclaration */);
+            }
+        }
+        /**
+         * Hooks node substitutions.
+         *
+         * @param hint The context for the emitter.
+         * @param node The node to substitute.
+         */
+        function onSubstituteNode(hint, node) {
+            node = previousOnSubstituteNode(hint, node);
+            if (hint === 1 /* Expression */) {
+                return substituteExpression(node);
+            }
+            if (ts.isIdentifier(node)) {
+                return substituteIdentifier(node);
+            }
+            return node;
+        }
+        /**
+         * Hooks substitutions for non-expression identifiers.
+         */
+        function substituteIdentifier(node) {
+            // Only substitute the identifier if we have enabled substitutions for block-scoped
+            // bindings.
+            if (enabledSubstitutions & 2 /* BlockScopedBindings */ && !ts.isInternalName(node)) {
+                var original = ts.getParseTreeNode(node, ts.isIdentifier);
+                if (original && isNameOfDeclarationWithCollidingName(original)) {
+                    return ts.setTextRange(ts.getGeneratedNameForNode(original), node);
+                }
+            }
+            return node;
+        }
+        /**
+         * Determines whether a name is the name of a declaration with a colliding name.
+         * NOTE: This function expects to be called with an original source tree node.
+         *
+         * @param node An original source tree node.
+         */
+        function isNameOfDeclarationWithCollidingName(node) {
+            switch (node.parent.kind) {
+                case 182 /* BindingElement */:
+                case 235 /* ClassDeclaration */:
+                case 238 /* EnumDeclaration */:
+                case 232 /* VariableDeclaration */:
+                    return node.parent.name === node
+                        && resolver.isDeclarationWithCollidingName(node.parent);
+            }
+            return false;
+        }
+        /**
+         * Substitutes an expression.
+         *
+         * @param node An Expression node.
+         */
+        function substituteExpression(node) {
+            switch (node.kind) {
+                case 71 /* Identifier */:
+                    return substituteExpressionIdentifier(node);
+                case 99 /* ThisKeyword */:
+                    return substituteThisKeyword(node);
+            }
+            return node;
+        }
+        /**
+         * Substitutes an expression identifier.
+         *
+         * @param node An Identifier node.
+         */
+        function substituteExpressionIdentifier(node) {
+            if (enabledSubstitutions & 2 /* BlockScopedBindings */ && !ts.isInternalName(node)) {
+                var declaration = resolver.getReferencedDeclarationWithCollidingName(node);
+                if (declaration && !(ts.isClassLike(declaration) && isPartOfClassBody(declaration, node))) {
+                    return ts.setTextRange(ts.getGeneratedNameForNode(ts.getNameOfDeclaration(declaration)), node);
+                }
+            }
+            return node;
+        }
+        function isPartOfClassBody(declaration, node) {
+            var currentNode = ts.getParseTreeNode(node);
+            if (!currentNode || currentNode === declaration || currentNode.end <= declaration.pos || currentNode.pos >= declaration.end) {
+                // if the node has no correlation to a parse tree node, its definitely not
+                // part of the body.
+                // if the node is outside of the document range of the declaration, its
+                // definitely not part of the body.
+                return false;
+            }
+            var blockScope = ts.getEnclosingBlockScopeContainer(declaration);
+            while (currentNode) {
+                if (currentNode === blockScope || currentNode === declaration) {
+                    // if we are in the enclosing block scope of the declaration, we are definitely
+                    // not inside the class body.
+                    return false;
+                }
+                if (ts.isClassElement(currentNode) && currentNode.parent === declaration) {
+                    return true;
+                }
+                currentNode = currentNode.parent;
+            }
+            return false;
+        }
+        /**
+         * Substitutes `this` when contained within an arrow function.
+         *
+         * @param node The ThisKeyword node.
+         */
+        function substituteThisKeyword(node) {
+            if (enabledSubstitutions & 1 /* CapturedThis */
+                && hierarchyFacts & 16 /* CapturesThis */) {
+                return ts.setTextRange(ts.createFileLevelUniqueName("_this"), node);
+            }
+            return node;
+        }
+        function getClassMemberPrefix(node, member) {
+            return ts.hasModifier(member, 32 /* Static */)
+                ? ts.getInternalName(node)
+                : ts.createPropertyAccess(ts.getInternalName(node), "prototype");
+        }
+        function hasSynthesizedDefaultSuperCall(constructor, hasExtendsClause) {
+            if (!constructor || !hasExtendsClause) {
+                return false;
+            }
+            if (ts.some(constructor.parameters)) {
+                return false;
+            }
+            var statement = ts.firstOrUndefined(constructor.body.statements);
+            if (!statement || !ts.nodeIsSynthesized(statement) || statement.kind !== 216 /* ExpressionStatement */) {
+                return false;
+            }
+            var statementExpression = statement.expression;
+            if (!ts.nodeIsSynthesized(statementExpression) || statementExpression.kind !== 187 /* CallExpression */) {
+                return false;
+            }
+            var callTarget = statementExpression.expression;
+            if (!ts.nodeIsSynthesized(callTarget) || callTarget.kind !== 97 /* SuperKeyword */) {
+                return false;
+            }
+            var callArgument = ts.singleOrUndefined(statementExpression.arguments);
+            if (!callArgument || !ts.nodeIsSynthesized(callArgument) || callArgument.kind !== 204 /* SpreadElement */) {
+                return false;
+            }
+            var expression = callArgument.expression;
+            return ts.isIdentifier(expression) && expression.escapedText === "arguments";
+        }
+    }
+    ts.transformES2015 = transformES2015;
+    function createExtendsHelper(context, name) {
+        context.requestEmitHelper(extendsHelper);
+        return ts.createCall(ts.getHelperName("__extends"), 
+        /*typeArguments*/ undefined, [
+            name,
+            ts.createFileLevelUniqueName("_super")
+        ]);
+    }
+    function createTemplateObjectHelper(context, cooked, raw) {
+        context.requestEmitHelper(templateObjectHelper);
+        return ts.createCall(ts.getHelperName("__makeTemplateObject"), 
+        /*typeArguments*/ undefined, [
+            cooked,
+            raw
+        ]);
+    }
+    var extendsHelper = {
+        name: "typescript:extends",
+        scoped: false,
+        priority: 0,
+        text: "\n            var __extends = (this && this.__extends) || (function () {\n                var extendStatics = Object.setPrototypeOf ||\n                    ({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||\n                    function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };\n                return function (d, b) {\n                    extendStatics(d, b);\n                    function __() { this.constructor = d; }\n                    d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());\n                };\n            })();"
+    };
+    var templateObjectHelper = {
+        name: "typescript:makeTemplateObject",
+        scoped: false,
+        priority: 0,
+        text: "\n            var __makeTemplateObject = (this && this.__makeTemplateObject) || function (cooked, raw) {\n                if (Object.defineProperty) { Object.defineProperty(cooked, \"raw\", { value: raw }); } else { cooked.raw = raw; }\n                return cooked;\n            };"
+    };
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    /**
+     * Transforms ES5 syntax into ES3 syntax.
+     *
+     * @param context Context and state information for the transformation.
+     */
+    function transformES5(context) {
+        var compilerOptions = context.getCompilerOptions();
+        // enable emit notification only if using --jsx preserve or react-native
+        var previousOnEmitNode;
+        var noSubstitution;
+        if (compilerOptions.jsx === 1 /* Preserve */ || compilerOptions.jsx === 3 /* ReactNative */) {
+            previousOnEmitNode = context.onEmitNode;
+            context.onEmitNode = onEmitNode;
+            context.enableEmitNotification(257 /* JsxOpeningElement */);
+            context.enableEmitNotification(258 /* JsxClosingElement */);
+            context.enableEmitNotification(256 /* JsxSelfClosingElement */);
+            noSubstitution = [];
+        }
+        var previousOnSubstituteNode = context.onSubstituteNode;
+        context.onSubstituteNode = onSubstituteNode;
+        context.enableSubstitution(185 /* PropertyAccessExpression */);
+        context.enableSubstitution(270 /* PropertyAssignment */);
+        return ts.chainBundle(transformSourceFile);
+        /**
+         * Transforms an ES5 source file to ES3.
+         *
+         * @param node A SourceFile
+         */
+        function transformSourceFile(node) {
+            return node;
+        }
+        /**
+         * Called by the printer just before a node is printed.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to emit.
+         * @param emitCallback A callback used to emit the node.
+         */
+        function onEmitNode(hint, node, emitCallback) {
+            switch (node.kind) {
+                case 257 /* JsxOpeningElement */:
+                case 258 /* JsxClosingElement */:
+                case 256 /* JsxSelfClosingElement */:
+                    var tagName = node.tagName;
+                    noSubstitution[ts.getOriginalNodeId(tagName)] = true;
+                    break;
+            }
+            previousOnEmitNode(hint, node, emitCallback);
+        }
+        /**
+         * Hooks node substitutions.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to substitute.
+         */
+        function onSubstituteNode(hint, node) {
+            if (node.id && noSubstitution && noSubstitution[node.id]) {
+                return previousOnSubstituteNode(hint, node);
+            }
+            node = previousOnSubstituteNode(hint, node);
+            if (ts.isPropertyAccessExpression(node)) {
+                return substitutePropertyAccessExpression(node);
+            }
+            else if (ts.isPropertyAssignment(node)) {
+                return substitutePropertyAssignment(node);
+            }
+            return node;
+        }
+        /**
+         * Substitutes a PropertyAccessExpression whose name is a reserved word.
+         *
+         * @param node A PropertyAccessExpression
+         */
+        function substitutePropertyAccessExpression(node) {
+            var literalName = trySubstituteReservedName(node.name);
+            if (literalName) {
+                return ts.setTextRange(ts.createElementAccess(node.expression, literalName), node);
+            }
+            return node;
+        }
+        /**
+         * Substitutes a PropertyAssignment whose name is a reserved word.
+         *
+         * @param node A PropertyAssignment
+         */
+        function substitutePropertyAssignment(node) {
+            var literalName = ts.isIdentifier(node.name) && trySubstituteReservedName(node.name);
+            if (literalName) {
+                return ts.updatePropertyAssignment(node, literalName, node.initializer);
+            }
+            return node;
+        }
+        /**
+         * If an identifier name is a reserved word, returns a string literal for the name.
+         *
+         * @param name An Identifier
+         */
+        function trySubstituteReservedName(name) {
+            var token = name.originalKeywordKind || (ts.nodeIsSynthesized(name) ? ts.stringToToken(ts.idText(name)) : undefined);
+            if (token !== undefined && token >= 72 /* FirstReservedWord */ && token <= 107 /* LastReservedWord */) {
+                return ts.setTextRange(ts.createLiteral(name), name);
+            }
+            return undefined;
+        }
+    }
+    ts.transformES5 = transformES5;
+})(ts || (ts = {}));
+// Transforms generator functions into a compatible ES5 representation with similar runtime
+// semantics. This is accomplished by first transforming the body of each generator
+// function into an intermediate representation that is the compiled into a JavaScript
+// switch statement.
+//
+// Many functions in this transformer will contain comments indicating the expected
+// intermediate representation. For illustrative purposes, the following intermediate
+// language is used to define this intermediate representation:
+//
+//  .nop                            - Performs no operation.
+//  .local NAME, ...                - Define local variable declarations.
+//  .mark LABEL                     - Mark the location of a label.
+//  .br LABEL                       - Jump to a label. If jumping out of a protected
+//                                    region, all .finally blocks are executed.
+//  .brtrue LABEL, (x)              - Jump to a label IIF the expression `x` is truthy.
+//                                    If jumping out of a protected region, all .finally
+//                                    blocks are executed.
+//  .brfalse LABEL, (x)             - Jump to a label IIF the expression `x` is falsey.
+//                                    If jumping out of a protected region, all .finally
+//                                    blocks are executed.
+//  .yield (x)                      - Yield the value of the optional expression `x`.
+//                                    Resume at the next label.
+//  .yieldstar (x)                  - Delegate yield to the value of the optional
+//                                    expression `x`. Resume at the next label.
+//                                    NOTE: `x` must be an Iterator, not an Iterable.
+//  .loop CONTINUE, BREAK           - Marks the beginning of a loop. Any "continue" or
+//                                    "break" abrupt completions jump to the CONTINUE or
+//                                    BREAK labels, respectively.
+//  .endloop                        - Marks the end of a loop.
+//  .with (x)                       - Marks the beginning of a WithStatement block, using
+//                                    the supplied expression.
+//  .endwith                        - Marks the end of a WithStatement.
+//  .switch                         - Marks the beginning of a SwitchStatement.
+//  .endswitch                      - Marks the end of a SwitchStatement.
+//  .labeled NAME                   - Marks the beginning of a LabeledStatement with the
+//                                    supplied name.
+//  .endlabeled                     - Marks the end of a LabeledStatement.
+//  .try TRY, CATCH, FINALLY, END   - Marks the beginning of a protected region, and the
+//                                    labels for each block.
+//  .catch (x)                      - Marks the beginning of a catch block.
+//  .finally                        - Marks the beginning of a finally block.
+//  .endfinally                     - Marks the end of a finally block.
+//  .endtry                         - Marks the end of a protected region.
+//  .throw (x)                      - Throws the value of the expression `x`.
+//  .return (x)                     - Returns the value of the expression `x`.
+//
+// In addition, the illustrative intermediate representation introduces some special
+// variables:
+//
+//  %sent%                          - Either returns the next value sent to the generator,
+//                                    returns the result of a delegated yield, or throws
+//                                    the exception sent to the generator.
+//  %error%                         - Returns the value of the current exception in a
+//                                    catch block.
+//
+// This intermediate representation is then compiled into JavaScript syntax. The resulting
+// compilation output looks something like the following:
+//
+//  function f() {
+//      var /*locals*/;
+//      /*functions*/
+//      return __generator(function (state) {
+//          switch (state.label) {
+//              /*cases per label*/
+//          }
+//      });
+//  }
+//
+// Each of the above instructions corresponds to JavaScript emit similar to the following:
+//
+//  .local NAME                   | var NAME;
+// -------------------------------|----------------------------------------------
+//  .mark LABEL                   | case LABEL:
+// -------------------------------|----------------------------------------------
+//  .br LABEL                     |     return [3 /*break*/, LABEL];
+// -------------------------------|----------------------------------------------
+//  .brtrue LABEL, (x)            |     if (x) return [3 /*break*/, LABEL];
+// -------------------------------|----------------------------------------------
+//  .brfalse LABEL, (x)           |     if (!(x)) return [3, /*break*/, LABEL];
+// -------------------------------|----------------------------------------------
+//  .yield (x)                    |     return [4 /*yield*/, x];
+//  .mark RESUME                  | case RESUME:
+//      a = %sent%;               |     a = state.sent();
+// -------------------------------|----------------------------------------------
+//  .yieldstar (x)                |     return [5 /*yield**/, x];
+//  .mark RESUME                  | case RESUME:
+//      a = %sent%;               |     a = state.sent();
+// -------------------------------|----------------------------------------------
+//  .with (_a)                    |     with (_a) {
+//      a();                      |         a();
+//                                |     }
+//                                |     state.label = LABEL;
+//  .mark LABEL                   | case LABEL:
+//                                |     with (_a) {
+//      b();                      |         b();
+//                                |     }
+//  .endwith                      |
+// -------------------------------|----------------------------------------------
+//                                | case 0:
+//                                |     state.trys = [];
+//                                | ...
+//  .try TRY, CATCH, FINALLY, END |
+//  .mark TRY                     | case TRY:
+//                                |     state.trys.push([TRY, CATCH, FINALLY, END]);
+//  .nop                          |
+//      a();                      |     a();
+//  .br END                       |     return [3 /*break*/, END];
+//  .catch (e)                    |
+//  .mark CATCH                   | case CATCH:
+//                                |     e = state.sent();
+//      b();                      |     b();
+//  .br END                       |     return [3 /*break*/, END];
+//  .finally                      |
+//  .mark FINALLY                 | case FINALLY:
+//      c();                      |     c();
+//  .endfinally                   |     return [7 /*endfinally*/];
+//  .endtry                       |
+//  .mark END                     | case END:
+/*@internal*/
+var ts;
+(function (ts) {
+    var OpCode;
+    (function (OpCode) {
+        OpCode[OpCode["Nop"] = 0] = "Nop";
+        OpCode[OpCode["Statement"] = 1] = "Statement";
+        OpCode[OpCode["Assign"] = 2] = "Assign";
+        OpCode[OpCode["Break"] = 3] = "Break";
+        OpCode[OpCode["BreakWhenTrue"] = 4] = "BreakWhenTrue";
+        OpCode[OpCode["BreakWhenFalse"] = 5] = "BreakWhenFalse";
+        OpCode[OpCode["Yield"] = 6] = "Yield";
+        OpCode[OpCode["YieldStar"] = 7] = "YieldStar";
+        OpCode[OpCode["Return"] = 8] = "Return";
+        OpCode[OpCode["Throw"] = 9] = "Throw";
+        OpCode[OpCode["Endfinally"] = 10] = "Endfinally"; // Marks the end of a `finally` block
+    })(OpCode || (OpCode = {}));
+    // whether a generated code block is opening or closing at the current operation for a FunctionBuilder
+    var BlockAction;
+    (function (BlockAction) {
+        BlockAction[BlockAction["Open"] = 0] = "Open";
+        BlockAction[BlockAction["Close"] = 1] = "Close";
+    })(BlockAction || (BlockAction = {}));
+    // the kind for a generated code block in a FunctionBuilder
+    var CodeBlockKind;
+    (function (CodeBlockKind) {
+        CodeBlockKind[CodeBlockKind["Exception"] = 0] = "Exception";
+        CodeBlockKind[CodeBlockKind["With"] = 1] = "With";
+        CodeBlockKind[CodeBlockKind["Switch"] = 2] = "Switch";
+        CodeBlockKind[CodeBlockKind["Loop"] = 3] = "Loop";
+        CodeBlockKind[CodeBlockKind["Labeled"] = 4] = "Labeled";
+    })(CodeBlockKind || (CodeBlockKind = {}));
+    // the state for a generated code exception block
+    var ExceptionBlockState;
+    (function (ExceptionBlockState) {
+        ExceptionBlockState[ExceptionBlockState["Try"] = 0] = "Try";
+        ExceptionBlockState[ExceptionBlockState["Catch"] = 1] = "Catch";
+        ExceptionBlockState[ExceptionBlockState["Finally"] = 2] = "Finally";
+        ExceptionBlockState[ExceptionBlockState["Done"] = 3] = "Done";
+    })(ExceptionBlockState || (ExceptionBlockState = {}));
+    // NOTE: changes to this enum should be reflected in the __generator helper.
+    var Instruction;
+    (function (Instruction) {
+        Instruction[Instruction["Next"] = 0] = "Next";
+        Instruction[Instruction["Throw"] = 1] = "Throw";
+        Instruction[Instruction["Return"] = 2] = "Return";
+        Instruction[Instruction["Break"] = 3] = "Break";
+        Instruction[Instruction["Yield"] = 4] = "Yield";
+        Instruction[Instruction["YieldStar"] = 5] = "YieldStar";
+        Instruction[Instruction["Catch"] = 6] = "Catch";
+        Instruction[Instruction["Endfinally"] = 7] = "Endfinally";
+    })(Instruction || (Instruction = {}));
+    function getInstructionName(instruction) {
+        switch (instruction) {
+            case 2 /* Return */: return "return";
+            case 3 /* Break */: return "break";
+            case 4 /* Yield */: return "yield";
+            case 5 /* YieldStar */: return "yield*";
+            case 7 /* Endfinally */: return "endfinally";
+            default: return undefined; // TODO: GH#18217
+        }
+    }
+    function transformGenerators(context) {
+        var resumeLexicalEnvironment = context.resumeLexicalEnvironment, endLexicalEnvironment = context.endLexicalEnvironment, hoistFunctionDeclaration = context.hoistFunctionDeclaration, hoistVariableDeclaration = context.hoistVariableDeclaration;
+        var compilerOptions = context.getCompilerOptions();
+        var languageVersion = ts.getEmitScriptTarget(compilerOptions);
+        var resolver = context.getEmitResolver();
+        var previousOnSubstituteNode = context.onSubstituteNode;
+        context.onSubstituteNode = onSubstituteNode;
+        var renamedCatchVariables;
+        var renamedCatchVariableDeclarations;
+        var inGeneratorFunctionBody;
+        var inStatementContainingYield;
+        // The following three arrays store information about generated code blocks.
+        // All three arrays are correlated by their index. This approach is used over allocating
+        // objects to store the same information to avoid GC overhead.
+        //
+        var blocks; // Information about the code block
+        var blockOffsets; // The operation offset at which a code block begins or ends
+        var blockActions; // Whether the code block is opened or closed
+        var blockStack; // A stack of currently open code blocks
+        // Labels are used to mark locations in the code that can be the target of a Break (jump)
+        // operation. These are translated into case clauses in a switch statement.
+        // The following two arrays are correlated by their index. This approach is used over
+        // allocating objects to store the same information to avoid GC overhead.
+        //
+        var labelOffsets; // The operation offset at which the label is defined.
+        var labelExpressions; // The NumericLiteral nodes bound to each label.
+        var nextLabelId = 1; // The next label id to use.
+        // Operations store information about generated code for the function body. This
+        // Includes things like statements, assignments, breaks (jumps), and yields.
+        // The following three arrays are correlated by their index. This approach is used over
+        // allocating objects to store the same information to avoid GC overhead.
+        //
+        var operations; // The operation to perform.
+        var operationArguments; // The arguments to the operation.
+        var operationLocations; // The source map location for the operation.
+        var state; // The name of the state object used by the generator at runtime.
+        // The following variables store information used by the `build` function:
+        //
+        var blockIndex = 0; // The index of the current block.
+        var labelNumber = 0; // The current label number.
+        var labelNumbers;
+        var lastOperationWasAbrupt; // Indicates whether the last operation was abrupt (break/continue).
+        var lastOperationWasCompletion; // Indicates whether the last operation was a completion (return/throw).
+        var clauses; // The case clauses generated for labels.
+        var statements; // The statements for the current label.
+        var exceptionBlockStack; // A stack of containing exception blocks.
+        var currentExceptionBlock; // The current exception block.
+        var withBlockStack; // A stack containing `with` blocks.
+        return ts.chainBundle(transformSourceFile);
+        function transformSourceFile(node) {
+            if (node.isDeclarationFile || (node.transformFlags & 512 /* ContainsGenerator */) === 0) {
+                return node;
+            }
+            var visited = ts.visitEachChild(node, visitor, context);
+            ts.addEmitHelpers(visited, context.readEmitHelpers());
+            return visited;
+        }
+        /**
+         * Visits a node.
+         *
+         * @param node The node to visit.
+         */
+        function visitor(node) {
+            var transformFlags = node.transformFlags;
+            if (inStatementContainingYield) {
+                return visitJavaScriptInStatementContainingYield(node);
+            }
+            else if (inGeneratorFunctionBody) {
+                return visitJavaScriptInGeneratorFunctionBody(node);
+            }
+            else if (transformFlags & 256 /* Generator */) {
+                return visitGenerator(node);
+            }
+            else if (transformFlags & 512 /* ContainsGenerator */) {
+                return ts.visitEachChild(node, visitor, context);
+            }
+            else {
+                return node;
+            }
+        }
+        /**
+         * Visits a node that is contained within a statement that contains yield.
+         *
+         * @param node The node to visit.
+         */
+        function visitJavaScriptInStatementContainingYield(node) {
+            switch (node.kind) {
+                case 218 /* DoStatement */:
+                    return visitDoStatement(node);
+                case 219 /* WhileStatement */:
+                    return visitWhileStatement(node);
+                case 227 /* SwitchStatement */:
+                    return visitSwitchStatement(node);
+                case 228 /* LabeledStatement */:
+                    return visitLabeledStatement(node);
+                default:
+                    return visitJavaScriptInGeneratorFunctionBody(node);
+            }
+        }
+        /**
+         * Visits a node that is contained within a generator function.
+         *
+         * @param node The node to visit.
+         */
+        function visitJavaScriptInGeneratorFunctionBody(node) {
+            switch (node.kind) {
+                case 234 /* FunctionDeclaration */:
+                    return visitFunctionDeclaration(node);
+                case 192 /* FunctionExpression */:
+                    return visitFunctionExpression(node);
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                    return visitAccessorDeclaration(node);
+                case 214 /* VariableStatement */:
+                    return visitVariableStatement(node);
+                case 220 /* ForStatement */:
+                    return visitForStatement(node);
+                case 221 /* ForInStatement */:
+                    return visitForInStatement(node);
+                case 224 /* BreakStatement */:
+                    return visitBreakStatement(node);
+                case 223 /* ContinueStatement */:
+                    return visitContinueStatement(node);
+                case 225 /* ReturnStatement */:
+                    return visitReturnStatement(node);
+                default:
+                    if (node.transformFlags & 16777216 /* ContainsYield */) {
+                        return visitJavaScriptContainingYield(node);
+                    }
+                    else if (node.transformFlags & (512 /* ContainsGenerator */ | 33554432 /* ContainsHoistedDeclarationOrCompletion */)) {
+                        return ts.visitEachChild(node, visitor, context);
+                    }
+                    else {
+                        return node;
+                    }
+            }
+        }
+        /**
+         * Visits a node that contains a YieldExpression.
+         *
+         * @param node The node to visit.
+         */
+        function visitJavaScriptContainingYield(node) {
+            switch (node.kind) {
+                case 200 /* BinaryExpression */:
+                    return visitBinaryExpression(node);
+                case 201 /* ConditionalExpression */:
+                    return visitConditionalExpression(node);
+                case 203 /* YieldExpression */:
+                    return visitYieldExpression(node);
+                case 183 /* ArrayLiteralExpression */:
+                    return visitArrayLiteralExpression(node);
+                case 184 /* ObjectLiteralExpression */:
+                    return visitObjectLiteralExpression(node);
+                case 186 /* ElementAccessExpression */:
+                    return visitElementAccessExpression(node);
+                case 187 /* CallExpression */:
+                    return visitCallExpression(node);
+                case 188 /* NewExpression */:
+                    return visitNewExpression(node);
+                default:
+                    return ts.visitEachChild(node, visitor, context);
+            }
+        }
+        /**
+         * Visits a generator function.
+         *
+         * @param node The node to visit.
+         */
+        function visitGenerator(node) {
+            switch (node.kind) {
+                case 234 /* FunctionDeclaration */:
+                    return visitFunctionDeclaration(node);
+                case 192 /* FunctionExpression */:
+                    return visitFunctionExpression(node);
+                default:
+                    return ts.Debug.failBadSyntaxKind(node);
+            }
+        }
+        /**
+         * Visits a function declaration.
+         *
+         * This will be called when one of the following conditions are met:
+         * - The function declaration is a generator function.
+         * - The function declaration is contained within the body of a generator function.
+         *
+         * @param node The node to visit.
+         */
+        function visitFunctionDeclaration(node) {
+            // Currently, we only support generators that were originally async functions.
+            if (node.asteriskToken) {
+                node = ts.setOriginalNode(ts.setTextRange(ts.createFunctionDeclaration(
+                /*decorators*/ undefined, node.modifiers, 
+                /*asteriskToken*/ undefined, node.name, 
+                /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+                /*type*/ undefined, transformGeneratorFunctionBody(node.body)), 
+                /*location*/ node), node);
+            }
+            else {
+                var savedInGeneratorFunctionBody = inGeneratorFunctionBody;
+                var savedInStatementContainingYield = inStatementContainingYield;
+                inGeneratorFunctionBody = false;
+                inStatementContainingYield = false;
+                node = ts.visitEachChild(node, visitor, context);
+                inGeneratorFunctionBody = savedInGeneratorFunctionBody;
+                inStatementContainingYield = savedInStatementContainingYield;
+            }
+            if (inGeneratorFunctionBody) {
+                // Function declarations in a generator function body are hoisted
+                // to the top of the lexical scope and elided from the current statement.
+                hoistFunctionDeclaration(node);
+                return undefined;
+            }
+            else {
+                return node;
+            }
+        }
+        /**
+         * Visits a function expression.
+         *
+         * This will be called when one of the following conditions are met:
+         * - The function expression is a generator function.
+         * - The function expression is contained within the body of a generator function.
+         *
+         * @param node The node to visit.
+         */
+        function visitFunctionExpression(node) {
+            // Currently, we only support generators that were originally async functions.
+            if (node.asteriskToken) {
+                node = ts.setOriginalNode(ts.setTextRange(ts.createFunctionExpression(
+                /*modifiers*/ undefined, 
+                /*asteriskToken*/ undefined, node.name, 
+                /*typeParameters*/ undefined, ts.visitParameterList(node.parameters, visitor, context), 
+                /*type*/ undefined, transformGeneratorFunctionBody(node.body)), 
+                /*location*/ node), node);
+            }
+            else {
+                var savedInGeneratorFunctionBody = inGeneratorFunctionBody;
+                var savedInStatementContainingYield = inStatementContainingYield;
+                inGeneratorFunctionBody = false;
+                inStatementContainingYield = false;
+                node = ts.visitEachChild(node, visitor, context);
+                inGeneratorFunctionBody = savedInGeneratorFunctionBody;
+                inStatementContainingYield = savedInStatementContainingYield;
+            }
+            return node;
+        }
+        /**
+         * Visits a get or set accessor declaration.
+         *
+         * This will be called when one of the following conditions are met:
+         * - The accessor is contained within the body of a generator function.
+         *
+         * @param node The node to visit.
+         */
+        function visitAccessorDeclaration(node) {
+            var savedInGeneratorFunctionBody = inGeneratorFunctionBody;
+            var savedInStatementContainingYield = inStatementContainingYield;
+            inGeneratorFunctionBody = false;
+            inStatementContainingYield = false;
+            node = ts.visitEachChild(node, visitor, context);
+            inGeneratorFunctionBody = savedInGeneratorFunctionBody;
+            inStatementContainingYield = savedInStatementContainingYield;
+            return node;
+        }
+        /**
+         * Transforms the body of a generator function declaration.
+         *
+         * @param node The function body to transform.
+         */
+        function transformGeneratorFunctionBody(body) {
+            // Save existing generator state
+            var statements = [];
+            var savedInGeneratorFunctionBody = inGeneratorFunctionBody;
+            var savedInStatementContainingYield = inStatementContainingYield;
+            var savedBlocks = blocks;
+            var savedBlockOffsets = blockOffsets;
+            var savedBlockActions = blockActions;
+            var savedBlockStack = blockStack;
+            var savedLabelOffsets = labelOffsets;
+            var savedLabelExpressions = labelExpressions;
+            var savedNextLabelId = nextLabelId;
+            var savedOperations = operations;
+            var savedOperationArguments = operationArguments;
+            var savedOperationLocations = operationLocations;
+            var savedState = state;
+            // Initialize generator state
+            inGeneratorFunctionBody = true;
+            inStatementContainingYield = false;
+            blocks = undefined;
+            blockOffsets = undefined;
+            blockActions = undefined;
+            blockStack = undefined;
+            labelOffsets = undefined;
+            labelExpressions = undefined;
+            nextLabelId = 1;
+            operations = undefined;
+            operationArguments = undefined;
+            operationLocations = undefined;
+            state = ts.createTempVariable(/*recordTempVariable*/ undefined);
+            // Build the generator
+            resumeLexicalEnvironment();
+            var statementOffset = ts.addPrologue(statements, body.statements, /*ensureUseStrict*/ false, visitor);
+            transformAndEmitStatements(body.statements, statementOffset);
+            var buildResult = build();
+            ts.prependStatements(statements, endLexicalEnvironment());
+            statements.push(ts.createReturn(buildResult));
+            // Restore previous generator state
+            inGeneratorFunctionBody = savedInGeneratorFunctionBody;
+            inStatementContainingYield = savedInStatementContainingYield;
+            blocks = savedBlocks;
+            blockOffsets = savedBlockOffsets;
+            blockActions = savedBlockActions;
+            blockStack = savedBlockStack;
+            labelOffsets = savedLabelOffsets;
+            labelExpressions = savedLabelExpressions;
+            nextLabelId = savedNextLabelId;
+            operations = savedOperations;
+            operationArguments = savedOperationArguments;
+            operationLocations = savedOperationLocations;
+            state = savedState;
+            return ts.setTextRange(ts.createBlock(statements, body.multiLine), body);
+        }
+        /**
+         * Visits a variable statement.
+         *
+         * This will be called when one of the following conditions are met:
+         * - The variable statement is contained within the body of a generator function.
+         *
+         * @param node The node to visit.
+         */
+        function visitVariableStatement(node) {
+            if (node.transformFlags & 16777216 /* ContainsYield */) {
+                transformAndEmitVariableDeclarationList(node.declarationList);
+                return undefined;
+            }
+            else {
+                // Do not hoist custom prologues.
+                if (ts.getEmitFlags(node) & 1048576 /* CustomPrologue */) {
+                    return node;
+                }
+                for (var _i = 0, _a = node.declarationList.declarations; _i < _a.length; _i++) {
+                    var variable = _a[_i];
+                    hoistVariableDeclaration(variable.name);
+                }
+                var variables = ts.getInitializedVariables(node.declarationList);
+                if (variables.length === 0) {
+                    return undefined;
+                }
+                return ts.setSourceMapRange(ts.createStatement(ts.inlineExpressions(ts.map(variables, transformInitializedVariable))), node);
+            }
+        }
+        /**
+         * Visits a binary expression.
+         *
+         * This will be called when one of the following conditions are met:
+         * - The node contains a YieldExpression.
+         *
+         * @param node The node to visit.
+         */
+        function visitBinaryExpression(node) {
+            var assoc = ts.getExpressionAssociativity(node);
+            switch (assoc) {
+                case 0 /* Left */:
+                    return visitLeftAssociativeBinaryExpression(node);
+                case 1 /* Right */:
+                    return visitRightAssociativeBinaryExpression(node);
+                default:
+                    return ts.Debug.assertNever(assoc);
+            }
+        }
+        function isCompoundAssignment(kind) {
+            return kind >= 59 /* FirstCompoundAssignment */
+                && kind <= 70 /* LastCompoundAssignment */;
+        }
+        function getOperatorForCompoundAssignment(kind) {
+            switch (kind) {
+                case 59 /* PlusEqualsToken */: return 37 /* PlusToken */;
+                case 60 /* MinusEqualsToken */: return 38 /* MinusToken */;
+                case 61 /* AsteriskEqualsToken */: return 39 /* AsteriskToken */;
+                case 62 /* AsteriskAsteriskEqualsToken */: return 40 /* AsteriskAsteriskToken */;
+                case 63 /* SlashEqualsToken */: return 41 /* SlashToken */;
+                case 64 /* PercentEqualsToken */: return 42 /* PercentToken */;
+                case 65 /* LessThanLessThanEqualsToken */: return 45 /* LessThanLessThanToken */;
+                case 66 /* GreaterThanGreaterThanEqualsToken */: return 46 /* GreaterThanGreaterThanToken */;
+                case 67 /* GreaterThanGreaterThanGreaterThanEqualsToken */: return 47 /* GreaterThanGreaterThanGreaterThanToken */;
+                case 68 /* AmpersandEqualsToken */: return 48 /* AmpersandToken */;
+                case 69 /* BarEqualsToken */: return 49 /* BarToken */;
+                case 70 /* CaretEqualsToken */: return 50 /* CaretToken */;
+            }
+        }
+        /**
+         * Visits a right-associative binary expression containing `yield`.
+         *
+         * @param node The node to visit.
+         */
+        function visitRightAssociativeBinaryExpression(node) {
+            var left = node.left, right = node.right;
+            if (containsYield(right)) {
+                var target = void 0;
+                switch (left.kind) {
+                    case 185 /* PropertyAccessExpression */:
+                        // [source]
+                        //      a.b = yield;
+                        //
+                        // [intermediate]
+                        //  .local _a
+                        //      _a = a;
+                        //  .yield resumeLabel
+                        //  .mark resumeLabel
+                        //      _a.b = %sent%;
+                        target = ts.updatePropertyAccess(left, cacheExpression(ts.visitNode(left.expression, visitor, ts.isLeftHandSideExpression)), left.name);
+                        break;
+                    case 186 /* ElementAccessExpression */:
+                        // [source]
+                        //      a[b] = yield;
+                        //
+                        // [intermediate]
+                        //  .local _a, _b
+                        //      _a = a;
+                        //      _b = b;
+                        //  .yield resumeLabel
+                        //  .mark resumeLabel
+                        //      _a[_b] = %sent%;
+                        target = ts.updateElementAccess(left, cacheExpression(ts.visitNode(left.expression, visitor, ts.isLeftHandSideExpression)), cacheExpression(ts.visitNode(left.argumentExpression, visitor, ts.isExpression)));
+                        break;
+                    default:
+                        target = ts.visitNode(left, visitor, ts.isExpression);
+                        break;
+                }
+                var operator = node.operatorToken.kind;
+                if (isCompoundAssignment(operator)) {
+                    return ts.setTextRange(ts.createAssignment(target, ts.setTextRange(ts.createBinary(cacheExpression(target), getOperatorForCompoundAssignment(operator), ts.visitNode(right, visitor, ts.isExpression)), node)), node);
+                }
+                else {
+                    return ts.updateBinary(node, target, ts.visitNode(right, visitor, ts.isExpression));
+                }
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitLeftAssociativeBinaryExpression(node) {
+            if (containsYield(node.right)) {
+                if (ts.isLogicalOperator(node.operatorToken.kind)) {
+                    return visitLogicalBinaryExpression(node);
+                }
+                else if (node.operatorToken.kind === 26 /* CommaToken */) {
+                    return visitCommaExpression(node);
+                }
+                // [source]
+                //      a() + (yield) + c()
+                //
+                // [intermediate]
+                //  .local _a
+                //      _a = a();
+                //  .yield resumeLabel
+                //      _a + %sent% + c()
+                var clone_4 = ts.getMutableClone(node);
+                clone_4.left = cacheExpression(ts.visitNode(node.left, visitor, ts.isExpression));
+                clone_4.right = ts.visitNode(node.right, visitor, ts.isExpression);
+                return clone_4;
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        /**
+         * Visits a logical binary expression containing `yield`.
+         *
+         * @param node A node to visit.
+         */
+        function visitLogicalBinaryExpression(node) {
+            // Logical binary expressions (`&&` and `||`) are shortcutting expressions and need
+            // to be transformed as such:
+            //
+            // [source]
+            //      x = a() && yield;
+            //
+            // [intermediate]
+            //  .local _a
+            //      _a = a();
+            //  .brfalse resultLabel, (_a)
+            //  .yield resumeLabel
+            //  .mark resumeLabel
+            //      _a = %sent%;
+            //  .mark resultLabel
+            //      x = _a;
+            //
+            // [source]
+            //      x = a() || yield;
+            //
+            // [intermediate]
+            //  .local _a
+            //      _a = a();
+            //  .brtrue resultLabel, (_a)
+            //  .yield resumeLabel
+            //  .mark resumeLabel
+            //      _a = %sent%;
+            //  .mark resultLabel
+            //      x = _a;
+            var resultLabel = defineLabel();
+            var resultLocal = declareLocal();
+            emitAssignment(resultLocal, ts.visitNode(node.left, visitor, ts.isExpression), /*location*/ node.left);
+            if (node.operatorToken.kind === 53 /* AmpersandAmpersandToken */) {
+                // Logical `&&` shortcuts when the left-hand operand is falsey.
+                emitBreakWhenFalse(resultLabel, resultLocal, /*location*/ node.left);
+            }
+            else {
+                // Logical `||` shortcuts when the left-hand operand is truthy.
+                emitBreakWhenTrue(resultLabel, resultLocal, /*location*/ node.left);
+            }
+            emitAssignment(resultLocal, ts.visitNode(node.right, visitor, ts.isExpression), /*location*/ node.right);
+            markLabel(resultLabel);
+            return resultLocal;
+        }
+        /**
+         * Visits a comma expression containing `yield`.
+         *
+         * @param node The node to visit.
+         */
+        function visitCommaExpression(node) {
+            // [source]
+            //      x = a(), yield, b();
+            //
+            // [intermediate]
+            //      a();
+            //  .yield resumeLabel
+            //  .mark resumeLabel
+            //      x = %sent%, b();
+            var pendingExpressions = [];
+            visit(node.left);
+            visit(node.right);
+            return ts.inlineExpressions(pendingExpressions);
+            function visit(node) {
+                if (ts.isBinaryExpression(node) && node.operatorToken.kind === 26 /* CommaToken */) {
+                    visit(node.left);
+                    visit(node.right);
+                }
+                else {
+                    if (containsYield(node) && pendingExpressions.length > 0) {
+                        emitWorker(1 /* Statement */, [ts.createStatement(ts.inlineExpressions(pendingExpressions))]);
+                        pendingExpressions = [];
+                    }
+                    pendingExpressions.push(ts.visitNode(node, visitor, ts.isExpression));
+                }
+            }
+        }
+        /**
+         * Visits a conditional expression containing `yield`.
+         *
+         * @param node The node to visit.
+         */
+        function visitConditionalExpression(node) {
+            // [source]
+            //      x = a() ? yield : b();
+            //
+            // [intermediate]
+            //  .local _a
+            //  .brfalse whenFalseLabel, (a())
+            //  .yield resumeLabel
+            //  .mark resumeLabel
+            //      _a = %sent%;
+            //  .br resultLabel
+            //  .mark whenFalseLabel
+            //      _a = b();
+            //  .mark resultLabel
+            //      x = _a;
+            // We only need to perform a specific transformation if a `yield` expression exists
+            // in either the `whenTrue` or `whenFalse` branches.
+            // A `yield` in the condition will be handled by the normal visitor.
+            if (containsYield(node.whenTrue) || containsYield(node.whenFalse)) {
+                var whenFalseLabel = defineLabel();
+                var resultLabel = defineLabel();
+                var resultLocal = declareLocal();
+                emitBreakWhenFalse(whenFalseLabel, ts.visitNode(node.condition, visitor, ts.isExpression), /*location*/ node.condition);
+                emitAssignment(resultLocal, ts.visitNode(node.whenTrue, visitor, ts.isExpression), /*location*/ node.whenTrue);
+                emitBreak(resultLabel);
+                markLabel(whenFalseLabel);
+                emitAssignment(resultLocal, ts.visitNode(node.whenFalse, visitor, ts.isExpression), /*location*/ node.whenFalse);
+                markLabel(resultLabel);
+                return resultLocal;
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        /**
+         * Visits a `yield` expression.
+         *
+         * @param node The node to visit.
+         */
+        function visitYieldExpression(node) {
+            // [source]
+            //      x = yield a();
+            //
+            // [intermediate]
+            //  .yield resumeLabel, (a())
+            //  .mark resumeLabel
+            //      x = %sent%;
+            var resumeLabel = defineLabel();
+            var expression = ts.visitNode(node.expression, visitor, ts.isExpression);
+            if (node.asteriskToken) {
+                var iterator = (ts.getEmitFlags(node.expression) & 8388608 /* Iterator */) === 0
+                    ? ts.createValuesHelper(context, expression, /*location*/ node)
+                    : expression;
+                emitYieldStar(iterator, /*location*/ node);
+            }
+            else {
+                emitYield(expression, /*location*/ node);
+            }
+            markLabel(resumeLabel);
+            return createGeneratorResume(/*location*/ node);
+        }
+        /**
+         * Visits an ArrayLiteralExpression that contains a YieldExpression.
+         *
+         * @param node The node to visit.
+         */
+        function visitArrayLiteralExpression(node) {
+            return visitElements(node.elements, /*leadingElement*/ undefined, /*location*/ undefined, node.multiLine);
+        }
+        /**
+         * Visits an array of expressions containing one or more YieldExpression nodes
+         * and returns an expression for the resulting value.
+         *
+         * @param elements The elements to visit.
+         * @param multiLine Whether array literals created should be emitted on multiple lines.
+         */
+        function visitElements(elements, leadingElement, location, multiLine) {
+            // [source]
+            //      ar = [1, yield, 2];
+            //
+            // [intermediate]
+            //  .local _a
+            //      _a = [1];
+            //  .yield resumeLabel
+            //  .mark resumeLabel
+            //      ar = _a.concat([%sent%, 2]);
+            var numInitialElements = countInitialNodesWithoutYield(elements);
+            var temp;
+            if (numInitialElements > 0) {
+                temp = declareLocal();
+                var initialElements = ts.visitNodes(elements, visitor, ts.isExpression, 0, numInitialElements);
+                emitAssignment(temp, ts.createArrayLiteral(leadingElement
+                    ? [leadingElement].concat(initialElements) : initialElements));
+                leadingElement = undefined;
+            }
+            var expressions = ts.reduceLeft(elements, reduceElement, [], numInitialElements);
+            return temp
+                ? ts.createArrayConcat(temp, [ts.createArrayLiteral(expressions, multiLine)])
+                : ts.setTextRange(ts.createArrayLiteral(leadingElement ? [leadingElement].concat(expressions) : expressions, multiLine), location);
+            function reduceElement(expressions, element) {
+                if (containsYield(element) && expressions.length > 0) {
+                    var hasAssignedTemp = temp !== undefined;
+                    if (!temp) {
+                        temp = declareLocal();
+                    }
+                    emitAssignment(temp, hasAssignedTemp
+                        ? ts.createArrayConcat(temp, [ts.createArrayLiteral(expressions, multiLine)])
+                        : ts.createArrayLiteral(leadingElement ? [leadingElement].concat(expressions) : expressions, multiLine));
+                    leadingElement = undefined;
+                    expressions = [];
+                }
+                expressions.push(ts.visitNode(element, visitor, ts.isExpression));
+                return expressions;
+            }
+        }
+        function visitObjectLiteralExpression(node) {
+            // [source]
+            //      o = {
+            //          a: 1,
+            //          b: yield,
+            //          c: 2
+            //      };
+            //
+            // [intermediate]
+            //  .local _a
+            //      _a = {
+            //          a: 1
+            //      };
+            //  .yield resumeLabel
+            //  .mark resumeLabel
+            //      o = (_a.b = %sent%,
+            //          _a.c = 2,
+            //          _a);
+            var properties = node.properties;
+            var multiLine = node.multiLine;
+            var numInitialProperties = countInitialNodesWithoutYield(properties);
+            var temp = declareLocal();
+            emitAssignment(temp, ts.createObjectLiteral(ts.visitNodes(properties, visitor, ts.isObjectLiteralElementLike, 0, numInitialProperties), multiLine));
+            var expressions = ts.reduceLeft(properties, reduceProperty, [], numInitialProperties);
+            expressions.push(multiLine ? ts.startOnNewLine(ts.getMutableClone(temp)) : temp);
+            return ts.inlineExpressions(expressions);
+            function reduceProperty(expressions, property) {
+                if (containsYield(property) && expressions.length > 0) {
+                    emitStatement(ts.createStatement(ts.inlineExpressions(expressions)));
+                    expressions = [];
+                }
+                var expression = ts.createExpressionForObjectLiteralElementLike(node, property, temp);
+                var visited = ts.visitNode(expression, visitor, ts.isExpression);
+                if (visited) {
+                    if (multiLine) {
+                        ts.startOnNewLine(visited);
+                    }
+                    expressions.push(visited);
+                }
+                return expressions;
+            }
+        }
+        /**
+         * Visits an ElementAccessExpression that contains a YieldExpression.
+         *
+         * @param node The node to visit.
+         */
+        function visitElementAccessExpression(node) {
+            if (containsYield(node.argumentExpression)) {
+                // [source]
+                //      a = x[yield];
+                //
+                // [intermediate]
+                //  .local _a
+                //      _a = x;
+                //  .yield resumeLabel
+                //  .mark resumeLabel
+                //      a = _a[%sent%]
+                var clone_5 = ts.getMutableClone(node);
+                clone_5.expression = cacheExpression(ts.visitNode(node.expression, visitor, ts.isLeftHandSideExpression));
+                clone_5.argumentExpression = ts.visitNode(node.argumentExpression, visitor, ts.isExpression);
+                return clone_5;
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitCallExpression(node) {
+            if (!ts.isImportCall(node) && ts.forEach(node.arguments, containsYield)) {
+                // [source]
+                //      a.b(1, yield, 2);
+                //
+                // [intermediate]
+                //  .local _a, _b, _c
+                //      _b = (_a = a).b;
+                //      _c = [1];
+                //  .yield resumeLabel
+                //  .mark resumeLabel
+                //      _b.apply(_a, _c.concat([%sent%, 2]));
+                var _a = ts.createCallBinding(node.expression, hoistVariableDeclaration, languageVersion, /*cacheIdentifiers*/ true), target = _a.target, thisArg = _a.thisArg;
+                return ts.setOriginalNode(ts.createFunctionApply(cacheExpression(ts.visitNode(target, visitor, ts.isLeftHandSideExpression)), thisArg, visitElements(node.arguments), 
+                /*location*/ node), node);
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function visitNewExpression(node) {
+            if (ts.forEach(node.arguments, containsYield)) {
+                // [source]
+                //      new a.b(1, yield, 2);
+                //
+                // [intermediate]
+                //  .local _a, _b, _c
+                //      _b = (_a = a.b).bind;
+                //      _c = [1];
+                //  .yield resumeLabel
+                //  .mark resumeLabel
+                //      new (_b.apply(_a, _c.concat([%sent%, 2])));
+                var _a = ts.createCallBinding(ts.createPropertyAccess(node.expression, "bind"), hoistVariableDeclaration), target = _a.target, thisArg = _a.thisArg;
+                return ts.setOriginalNode(ts.setTextRange(ts.createNew(ts.createFunctionApply(cacheExpression(ts.visitNode(target, visitor, ts.isExpression)), thisArg, visitElements(node.arguments, 
+                /*leadingElement*/ ts.createVoidZero())), 
+                /*typeArguments*/ undefined, []), node), node);
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function transformAndEmitStatements(statements, start) {
+            if (start === void 0) { start = 0; }
+            var numStatements = statements.length;
+            for (var i = start; i < numStatements; i++) {
+                transformAndEmitStatement(statements[i]);
+            }
+        }
+        function transformAndEmitEmbeddedStatement(node) {
+            if (ts.isBlock(node)) {
+                transformAndEmitStatements(node.statements);
+            }
+            else {
+                transformAndEmitStatement(node);
+            }
+        }
+        function transformAndEmitStatement(node) {
+            var savedInStatementContainingYield = inStatementContainingYield;
+            if (!inStatementContainingYield) {
+                inStatementContainingYield = containsYield(node);
+            }
+            transformAndEmitStatementWorker(node);
+            inStatementContainingYield = savedInStatementContainingYield;
+        }
+        function transformAndEmitStatementWorker(node) {
+            switch (node.kind) {
+                case 213 /* Block */:
+                    return transformAndEmitBlock(node);
+                case 216 /* ExpressionStatement */:
+                    return transformAndEmitExpressionStatement(node);
+                case 217 /* IfStatement */:
+                    return transformAndEmitIfStatement(node);
+                case 218 /* DoStatement */:
+                    return transformAndEmitDoStatement(node);
+                case 219 /* WhileStatement */:
+                    return transformAndEmitWhileStatement(node);
+                case 220 /* ForStatement */:
+                    return transformAndEmitForStatement(node);
+                case 221 /* ForInStatement */:
+                    return transformAndEmitForInStatement(node);
+                case 223 /* ContinueStatement */:
+                    return transformAndEmitContinueStatement(node);
+                case 224 /* BreakStatement */:
+                    return transformAndEmitBreakStatement(node);
+                case 225 /* ReturnStatement */:
+                    return transformAndEmitReturnStatement(node);
+                case 226 /* WithStatement */:
+                    return transformAndEmitWithStatement(node);
+                case 227 /* SwitchStatement */:
+                    return transformAndEmitSwitchStatement(node);
+                case 228 /* LabeledStatement */:
+                    return transformAndEmitLabeledStatement(node);
+                case 229 /* ThrowStatement */:
+                    return transformAndEmitThrowStatement(node);
+                case 230 /* TryStatement */:
+                    return transformAndEmitTryStatement(node);
+                default:
+                    return emitStatement(ts.visitNode(node, visitor, ts.isStatement));
+            }
+        }
+        function transformAndEmitBlock(node) {
+            if (containsYield(node)) {
+                transformAndEmitStatements(node.statements);
+            }
+            else {
+                emitStatement(ts.visitNode(node, visitor, ts.isStatement));
+            }
+        }
+        function transformAndEmitExpressionStatement(node) {
+            emitStatement(ts.visitNode(node, visitor, ts.isStatement));
+        }
+        function transformAndEmitVariableDeclarationList(node) {
+            for (var _i = 0, _a = node.declarations; _i < _a.length; _i++) {
+                var variable = _a[_i];
+                var name = ts.getSynthesizedClone(variable.name);
+                ts.setCommentRange(name, variable.name);
+                hoistVariableDeclaration(name);
+            }
+            var variables = ts.getInitializedVariables(node);
+            var numVariables = variables.length;
+            var variablesWritten = 0;
+            var pendingExpressions = [];
+            while (variablesWritten < numVariables) {
+                for (var i = variablesWritten; i < numVariables; i++) {
+                    var variable = variables[i];
+                    if (containsYield(variable.initializer) && pendingExpressions.length > 0) {
+                        break;
+                    }
+                    pendingExpressions.push(transformInitializedVariable(variable));
+                }
+                if (pendingExpressions.length) {
+                    emitStatement(ts.createStatement(ts.inlineExpressions(pendingExpressions)));
+                    variablesWritten += pendingExpressions.length;
+                    pendingExpressions = [];
+                }
+            }
+            return undefined;
+        }
+        function transformInitializedVariable(node) {
+            return ts.setSourceMapRange(ts.createAssignment(ts.setSourceMapRange(ts.getSynthesizedClone(node.name), node.name), ts.visitNode(node.initializer, visitor, ts.isExpression)), node);
+        }
+        function transformAndEmitIfStatement(node) {
+            if (containsYield(node)) {
+                // [source]
+                //      if (x)
+                //          /*thenStatement*/
+                //      else
+                //          /*elseStatement*/
+                //
+                // [intermediate]
+                //  .brfalse elseLabel, (x)
+                //      /*thenStatement*/
+                //  .br endLabel
+                //  .mark elseLabel
+                //      /*elseStatement*/
+                //  .mark endLabel
+                if (containsYield(node.thenStatement) || containsYield(node.elseStatement)) {
+                    var endLabel = defineLabel();
+                    var elseLabel = node.elseStatement ? defineLabel() : undefined;
+                    emitBreakWhenFalse(node.elseStatement ? elseLabel : endLabel, ts.visitNode(node.expression, visitor, ts.isExpression), /*location*/ node.expression);
+                    transformAndEmitEmbeddedStatement(node.thenStatement);
+                    if (node.elseStatement) {
+                        emitBreak(endLabel);
+                        markLabel(elseLabel);
+                        transformAndEmitEmbeddedStatement(node.elseStatement);
+                    }
+                    markLabel(endLabel);
+                }
+                else {
+                    emitStatement(ts.visitNode(node, visitor, ts.isStatement));
+                }
+            }
+            else {
+                emitStatement(ts.visitNode(node, visitor, ts.isStatement));
+            }
+        }
+        function transformAndEmitDoStatement(node) {
+            if (containsYield(node)) {
+                // [source]
+                //      do {
+                //          /*body*/
+                //      }
+                //      while (i < 10);
+                //
+                // [intermediate]
+                //  .loop conditionLabel, endLabel
+                //  .mark loopLabel
+                //      /*body*/
+                //  .mark conditionLabel
+                //  .brtrue loopLabel, (i < 10)
+                //  .endloop
+                //  .mark endLabel
+                var conditionLabel = defineLabel();
+                var loopLabel = defineLabel();
+                beginLoopBlock(/*continueLabel*/ conditionLabel);
+                markLabel(loopLabel);
+                transformAndEmitEmbeddedStatement(node.statement);
+                markLabel(conditionLabel);
+                emitBreakWhenTrue(loopLabel, ts.visitNode(node.expression, visitor, ts.isExpression));
+                endLoopBlock();
+            }
+            else {
+                emitStatement(ts.visitNode(node, visitor, ts.isStatement));
+            }
+        }
+        function visitDoStatement(node) {
+            if (inStatementContainingYield) {
+                beginScriptLoopBlock();
+                node = ts.visitEachChild(node, visitor, context);
+                endLoopBlock();
+                return node;
+            }
+            else {
+                return ts.visitEachChild(node, visitor, context);
+            }
+        }
+        function transformAndEmitWhileStatement(node) {
+            if (containsYield(node)) {
+                // [source]
+                //      while (i < 10) {
+                //          /*body*/
+                //      }
+                //
+                // [intermediate]
+                //  .loop loopLabel, endLabel
+                //  .mark loopLabel
+                //  .brfalse endLabel, (i < 10)
+                //      /*body*/
+                //  .br loopLabel
+                //  .endloop
+                //  .mark endLabel
+                var loopLabel = defineLabel();
+                var endLabel = beginLoopBlock(loopLabel);
+                markLabel(loopLabel);
+                emitBreakWhenFalse(endLabel, ts.visitNode(node.expression, visitor, ts.isExpression));
+                transformAndEmitEmbeddedStatement(node.statement);
+                emitBreak(loopLabel);
+                endLoopBlock();
+            }
+            else {
+                emitStatement(ts.visitNode(node, visitor, ts.isStatement));
+            }
+        }
+        function visitWhileStatement(node) {
+            if (inStatementContainingYield) {
+                beginScriptLoopBlock();
+                node = ts.visitEachChild(node, visitor, context);
+                endLoopBlock();
+                return node;
+            }
+            else {
+                return ts.visitEachChild(node, visitor, context);
+            }
+        }
+        function transformAndEmitForStatement(node) {
+            if (containsYield(node)) {
+                // [source]
+                //      for (var i = 0; i < 10; i++) {
+                //          /*body*/
+                //      }
+                //
+                // [intermediate]
+                //  .local i
+                //      i = 0;
+                //  .loop incrementLabel, endLoopLabel
+                //  .mark conditionLabel
+                //  .brfalse endLoopLabel, (i < 10)
+                //      /*body*/
+                //  .mark incrementLabel
+                //      i++;
+                //  .br conditionLabel
+                //  .endloop
+                //  .mark endLoopLabel
+                var conditionLabel = defineLabel();
+                var incrementLabel = defineLabel();
+                var endLabel = beginLoopBlock(incrementLabel);
+                if (node.initializer) {
+                    var initializer = node.initializer;
+                    if (ts.isVariableDeclarationList(initializer)) {
+                        transformAndEmitVariableDeclarationList(initializer);
+                    }
+                    else {
+                        emitStatement(ts.setTextRange(ts.createStatement(ts.visitNode(initializer, visitor, ts.isExpression)), initializer));
+                    }
+                }
+                markLabel(conditionLabel);
+                if (node.condition) {
+                    emitBreakWhenFalse(endLabel, ts.visitNode(node.condition, visitor, ts.isExpression));
+                }
+                transformAndEmitEmbeddedStatement(node.statement);
+                markLabel(incrementLabel);
+                if (node.incrementor) {
+                    emitStatement(ts.setTextRange(ts.createStatement(ts.visitNode(node.incrementor, visitor, ts.isExpression)), node.incrementor));
+                }
+                emitBreak(conditionLabel);
+                endLoopBlock();
+            }
+            else {
+                emitStatement(ts.visitNode(node, visitor, ts.isStatement));
+            }
+        }
+        function visitForStatement(node) {
+            if (inStatementContainingYield) {
+                beginScriptLoopBlock();
+            }
+            var initializer = node.initializer;
+            if (initializer && ts.isVariableDeclarationList(initializer)) {
+                for (var _i = 0, _a = initializer.declarations; _i < _a.length; _i++) {
+                    var variable = _a[_i];
+                    hoistVariableDeclaration(variable.name);
+                }
+                var variables = ts.getInitializedVariables(initializer);
+                node = ts.updateFor(node, variables.length > 0
+                    ? ts.inlineExpressions(ts.map(variables, transformInitializedVariable))
+                    : undefined, ts.visitNode(node.condition, visitor, ts.isExpression), ts.visitNode(node.incrementor, visitor, ts.isExpression), ts.visitNode(node.statement, visitor, ts.isStatement, ts.liftToBlock));
+            }
+            else {
+                node = ts.visitEachChild(node, visitor, context);
+            }
+            if (inStatementContainingYield) {
+                endLoopBlock();
+            }
+            return node;
+        }
+        function transformAndEmitForInStatement(node) {
+            // TODO(rbuckton): Source map locations
+            if (containsYield(node)) {
+                // [source]
+                //      for (var p in o) {
+                //          /*body*/
+                //      }
+                //
+                // [intermediate]
+                //  .local _a, _b, _i
+                //      _a = [];
+                //      for (_b in o) _a.push(_b);
+                //      _i = 0;
+                //  .loop incrementLabel, endLoopLabel
+                //  .mark conditionLabel
+                //  .brfalse endLoopLabel, (_i < _a.length)
+                //      p = _a[_i];
+                //      /*body*/
+                //  .mark incrementLabel
+                //      _b++;
+                //  .br conditionLabel
+                //  .endloop
+                //  .mark endLoopLabel
+                var keysArray = declareLocal(); // _a
+                var key = declareLocal(); // _b
+                var keysIndex = ts.createLoopVariable(); // _i
+                var initializer = node.initializer;
+                hoistVariableDeclaration(keysIndex);
+                emitAssignment(keysArray, ts.createArrayLiteral());
+                emitStatement(ts.createForIn(key, ts.visitNode(node.expression, visitor, ts.isExpression), ts.createStatement(ts.createCall(ts.createPropertyAccess(keysArray, "push"), 
+                /*typeArguments*/ undefined, [key]))));
+                emitAssignment(keysIndex, ts.createLiteral(0));
+                var conditionLabel = defineLabel();
+                var incrementLabel = defineLabel();
+                var endLabel = beginLoopBlock(incrementLabel);
+                markLabel(conditionLabel);
+                emitBreakWhenFalse(endLabel, ts.createLessThan(keysIndex, ts.createPropertyAccess(keysArray, "length")));
+                var variable = void 0;
+                if (ts.isVariableDeclarationList(initializer)) {
+                    for (var _i = 0, _a = initializer.declarations; _i < _a.length; _i++) {
+                        var variable_1 = _a[_i];
+                        hoistVariableDeclaration(variable_1.name);
+                    }
+                    variable = ts.getSynthesizedClone(initializer.declarations[0].name);
+                }
+                else {
+                    variable = ts.visitNode(initializer, visitor, ts.isExpression);
+                    ts.Debug.assert(ts.isLeftHandSideExpression(variable));
+                }
+                emitAssignment(variable, ts.createElementAccess(keysArray, keysIndex));
+                transformAndEmitEmbeddedStatement(node.statement);
+                markLabel(incrementLabel);
+                emitStatement(ts.createStatement(ts.createPostfixIncrement(keysIndex)));
+                emitBreak(conditionLabel);
+                endLoopBlock();
+            }
+            else {
+                emitStatement(ts.visitNode(node, visitor, ts.isStatement));
+            }
+        }
+        function visitForInStatement(node) {
+            // [source]
+            //      for (var x in a) {
+            //          /*body*/
+            //      }
+            //
+            // [intermediate]
+            //  .local x
+            //  .loop
+            //      for (x in a) {
+            //          /*body*/
+            //      }
+            //  .endloop
+            if (inStatementContainingYield) {
+                beginScriptLoopBlock();
+            }
+            var initializer = node.initializer;
+            if (ts.isVariableDeclarationList(initializer)) {
+                for (var _i = 0, _a = initializer.declarations; _i < _a.length; _i++) {
+                    var variable = _a[_i];
+                    hoistVariableDeclaration(variable.name);
+                }
+                node = ts.updateForIn(node, initializer.declarations[0].name, ts.visitNode(node.expression, visitor, ts.isExpression), ts.visitNode(node.statement, visitor, ts.isStatement, ts.liftToBlock));
+            }
+            else {
+                node = ts.visitEachChild(node, visitor, context);
+            }
+            if (inStatementContainingYield) {
+                endLoopBlock();
+            }
+            return node;
+        }
+        function transformAndEmitContinueStatement(node) {
+            var label = findContinueTarget(node.label ? ts.idText(node.label) : undefined);
+            if (label > 0) {
+                emitBreak(label, /*location*/ node);
+            }
+            else {
+                // invalid continue without a containing loop. Leave the node as is, per #17875.
+                emitStatement(node);
+            }
+        }
+        function visitContinueStatement(node) {
+            if (inStatementContainingYield) {
+                var label = findContinueTarget(node.label && ts.idText(node.label));
+                if (label > 0) {
+                    return createInlineBreak(label, /*location*/ node);
+                }
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function transformAndEmitBreakStatement(node) {
+            var label = findBreakTarget(node.label ? ts.idText(node.label) : undefined);
+            if (label > 0) {
+                emitBreak(label, /*location*/ node);
+            }
+            else {
+                // invalid break without a containing loop, switch, or labeled statement. Leave the node as is, per #17875.
+                emitStatement(node);
+            }
+        }
+        function visitBreakStatement(node) {
+            if (inStatementContainingYield) {
+                var label = findBreakTarget(node.label && ts.idText(node.label));
+                if (label > 0) {
+                    return createInlineBreak(label, /*location*/ node);
+                }
+            }
+            return ts.visitEachChild(node, visitor, context);
+        }
+        function transformAndEmitReturnStatement(node) {
+            emitReturn(ts.visitNode(node.expression, visitor, ts.isExpression), 
+            /*location*/ node);
+        }
+        function visitReturnStatement(node) {
+            return createInlineReturn(ts.visitNode(node.expression, visitor, ts.isExpression), 
+            /*location*/ node);
+        }
+        function transformAndEmitWithStatement(node) {
+            if (containsYield(node)) {
+                // [source]
+                //      with (x) {
+                //          /*body*/
+                //      }
+                //
+                // [intermediate]
+                //  .with (x)
+                //      /*body*/
+                //  .endwith
+                beginWithBlock(cacheExpression(ts.visitNode(node.expression, visitor, ts.isExpression)));
+                transformAndEmitEmbeddedStatement(node.statement);
+                endWithBlock();
+            }
+            else {
+                emitStatement(ts.visitNode(node, visitor, ts.isStatement));
+            }
+        }
+        function transformAndEmitSwitchStatement(node) {
+            if (containsYield(node.caseBlock)) {
+                // [source]
+                //      switch (x) {
+                //          case a:
+                //              /*caseStatements*/
+                //          case b:
+                //              /*caseStatements*/
+                //          default:
+                //              /*defaultStatements*/
+                //      }
+                //
+                // [intermediate]
+                //  .local _a
+                //  .switch endLabel
+                //      _a = x;
+                //      switch (_a) {
+                //          case a:
+                //  .br clauseLabels[0]
+                //      }
+                //      switch (_a) {
+                //          case b:
+                //  .br clauseLabels[1]
+                //      }
+                //  .br clauseLabels[2]
+                //  .mark clauseLabels[0]
+                //      /*caseStatements*/
+                //  .mark clauseLabels[1]
+                //      /*caseStatements*/
+                //  .mark clauseLabels[2]
+                //      /*caseStatements*/
+                //  .endswitch
+                //  .mark endLabel
+                var caseBlock = node.caseBlock;
+                var numClauses = caseBlock.clauses.length;
+                var endLabel = beginSwitchBlock();
+                var expression = cacheExpression(ts.visitNode(node.expression, visitor, ts.isExpression));
+                // Create labels for each clause and find the index of the first default clause.
+                var clauseLabels = [];
+                var defaultClauseIndex = -1;
+                for (var i = 0; i < numClauses; i++) {
+                    var clause = caseBlock.clauses[i];
+                    clauseLabels.push(defineLabel());
+                    if (clause.kind === 267 /* DefaultClause */ && defaultClauseIndex === -1) {
+                        defaultClauseIndex = i;
+                    }
+                }
+                // Emit switch statements for each run of case clauses either from the first case
+                // clause or the next case clause with a `yield` in its expression, up to the next
+                // case clause with a `yield` in its expression.
+                var clausesWritten = 0;
+                var pendingClauses = [];
+                while (clausesWritten < numClauses) {
+                    var defaultClausesSkipped = 0;
+                    for (var i = clausesWritten; i < numClauses; i++) {
+                        var clause = caseBlock.clauses[i];
+                        if (clause.kind === 266 /* CaseClause */) {
+                            if (containsYield(clause.expression) && pendingClauses.length > 0) {
+                                break;
+                            }
+                            pendingClauses.push(ts.createCaseClause(ts.visitNode(clause.expression, visitor, ts.isExpression), [
+                                createInlineBreak(clauseLabels[i], /*location*/ clause.expression)
+                            ]));
+                        }
+                        else {
+                            defaultClausesSkipped++;
+                        }
+                    }
+                    if (pendingClauses.length) {
+                        emitStatement(ts.createSwitch(expression, ts.createCaseBlock(pendingClauses)));
+                        clausesWritten += pendingClauses.length;
+                        pendingClauses = [];
+                    }
+                    if (defaultClausesSkipped > 0) {
+                        clausesWritten += defaultClausesSkipped;
+                        defaultClausesSkipped = 0;
+                    }
+                }
+                if (defaultClauseIndex >= 0) {
+                    emitBreak(clauseLabels[defaultClauseIndex]);
+                }
+                else {
+                    emitBreak(endLabel);
+                }
+                for (var i = 0; i < numClauses; i++) {
+                    markLabel(clauseLabels[i]);
+                    transformAndEmitStatements(caseBlock.clauses[i].statements);
+                }
+                endSwitchBlock();
+            }
+            else {
+                emitStatement(ts.visitNode(node, visitor, ts.isStatement));
+            }
+        }
+        function visitSwitchStatement(node) {
+            if (inStatementContainingYield) {
+                beginScriptSwitchBlock();
+            }
+            node = ts.visitEachChild(node, visitor, context);
+            if (inStatementContainingYield) {
+                endSwitchBlock();
+            }
+            return node;
+        }
+        function transformAndEmitLabeledStatement(node) {
+            if (containsYield(node)) {
+                // [source]
+                //      x: {
+                //          /*body*/
+                //      }
+                //
+                // [intermediate]
+                //  .labeled "x", endLabel
+                //      /*body*/
+                //  .endlabeled
+                //  .mark endLabel
+                beginLabeledBlock(ts.idText(node.label));
+                transformAndEmitEmbeddedStatement(node.statement);
+                endLabeledBlock();
+            }
+            else {
+                emitStatement(ts.visitNode(node, visitor, ts.isStatement));
+            }
+        }
+        function visitLabeledStatement(node) {
+            if (inStatementContainingYield) {
+                beginScriptLabeledBlock(ts.idText(node.label));
+            }
+            node = ts.visitEachChild(node, visitor, context);
+            if (inStatementContainingYield) {
+                endLabeledBlock();
+            }
+            return node;
+        }
+        function transformAndEmitThrowStatement(node) {
+            emitThrow(ts.visitNode(node.expression, visitor, ts.isExpression), 
+            /*location*/ node);
+        }
+        function transformAndEmitTryStatement(node) {
+            if (containsYield(node)) {
+                // [source]
+                //      try {
+                //          /*tryBlock*/
+                //      }
+                //      catch (e) {
+                //          /*catchBlock*/
+                //      }
+                //      finally {
+                //          /*finallyBlock*/
+                //      }
+                //
+                // [intermediate]
+                //  .local _a
+                //  .try tryLabel, catchLabel, finallyLabel, endLabel
+                //  .mark tryLabel
+                //  .nop
+                //      /*tryBlock*/
+                //  .br endLabel
+                //  .catch
+                //  .mark catchLabel
+                //      _a = %error%;
+                //      /*catchBlock*/
+                //  .br endLabel
+                //  .finally
+                //  .mark finallyLabel
+                //      /*finallyBlock*/
+                //  .endfinally
+                //  .endtry
+                //  .mark endLabel
+                beginExceptionBlock();
+                transformAndEmitEmbeddedStatement(node.tryBlock);
+                if (node.catchClause) {
+                    beginCatchBlock(node.catchClause.variableDeclaration); // TODO: GH#18217
+                    transformAndEmitEmbeddedStatement(node.catchClause.block);
+                }
+                if (node.finallyBlock) {
+                    beginFinallyBlock();
+                    transformAndEmitEmbeddedStatement(node.finallyBlock);
+                }
+                endExceptionBlock();
+            }
+            else {
+                emitStatement(ts.visitEachChild(node, visitor, context));
+            }
+        }
+        function containsYield(node) {
+            return !!node && (node.transformFlags & 16777216 /* ContainsYield */) !== 0;
+        }
+        function countInitialNodesWithoutYield(nodes) {
+            var numNodes = nodes.length;
+            for (var i = 0; i < numNodes; i++) {
+                if (containsYield(nodes[i])) {
+                    return i;
+                }
+            }
+            return -1;
+        }
+        function onSubstituteNode(hint, node) {
+            node = previousOnSubstituteNode(hint, node);
+            if (hint === 1 /* Expression */) {
+                return substituteExpression(node);
+            }
+            return node;
+        }
+        function substituteExpression(node) {
+            if (ts.isIdentifier(node)) {
+                return substituteExpressionIdentifier(node);
+            }
+            return node;
+        }
+        function substituteExpressionIdentifier(node) {
+            if (!ts.isGeneratedIdentifier(node) && renamedCatchVariables && renamedCatchVariables.has(ts.idText(node))) {
+                var original = ts.getOriginalNode(node);
+                if (ts.isIdentifier(original) && original.parent) {
+                    var declaration = resolver.getReferencedValueDeclaration(original);
+                    if (declaration) {
+                        var name = renamedCatchVariableDeclarations[ts.getOriginalNodeId(declaration)];
+                        if (name) {
+                            var clone_6 = ts.getMutableClone(name);
+                            ts.setSourceMapRange(clone_6, node);
+                            ts.setCommentRange(clone_6, node);
+                            return clone_6;
+                        }
+                    }
+                }
+            }
+            return node;
+        }
+        function cacheExpression(node) {
+            var temp;
+            if (ts.isGeneratedIdentifier(node) || ts.getEmitFlags(node) & 4096 /* HelperName */) {
+                return node;
+            }
+            temp = ts.createTempVariable(hoistVariableDeclaration);
+            emitAssignment(temp, node, /*location*/ node);
+            return temp;
+        }
+        function declareLocal(name) {
+            var temp = name
+                ? ts.createUniqueName(name)
+                : ts.createTempVariable(/*recordTempVariable*/ undefined);
+            hoistVariableDeclaration(temp);
+            return temp;
+        }
+        /**
+         * Defines a label, uses as the target of a Break operation.
+         */
+        function defineLabel() {
+            if (!labelOffsets) {
+                labelOffsets = [];
+            }
+            var label = nextLabelId;
+            nextLabelId++;
+            labelOffsets[label] = -1;
+            return label;
+        }
+        /**
+         * Marks the current operation with the specified label.
+         */
+        function markLabel(label) {
+            ts.Debug.assert(labelOffsets !== undefined, "No labels were defined.");
+            labelOffsets[label] = operations ? operations.length : 0;
+        }
+        /**
+         * Begins a block operation (With, Break/Continue, Try/Catch/Finally)
+         *
+         * @param block Information about the block.
+         */
+        function beginBlock(block) {
+            if (!blocks) {
+                blocks = [];
+                blockActions = [];
+                blockOffsets = [];
+                blockStack = [];
+            }
+            var index = blockActions.length;
+            blockActions[index] = 0 /* Open */;
+            blockOffsets[index] = operations ? operations.length : 0;
+            blocks[index] = block;
+            blockStack.push(block);
+            return index;
+        }
+        /**
+         * Ends the current block operation.
+         */
+        function endBlock() {
+            var block = peekBlock();
+            if (block === undefined)
+                return ts.Debug.fail("beginBlock was never called.");
+            var index = blockActions.length;
+            blockActions[index] = 1 /* Close */;
+            blockOffsets[index] = operations ? operations.length : 0;
+            blocks[index] = block;
+            blockStack.pop();
+            return block;
+        }
+        /**
+         * Gets the current open block.
+         */
+        function peekBlock() {
+            return ts.lastOrUndefined(blockStack);
+        }
+        /**
+         * Gets the kind of the current open block.
+         */
+        function peekBlockKind() {
+            var block = peekBlock();
+            return block && block.kind;
+        }
+        /**
+         * Begins a code block for a generated `with` statement.
+         *
+         * @param expression An identifier representing expression for the `with` block.
+         */
+        function beginWithBlock(expression) {
+            var startLabel = defineLabel();
+            var endLabel = defineLabel();
+            markLabel(startLabel);
+            beginBlock({
+                kind: 1 /* With */,
+                expression: expression,
+                startLabel: startLabel,
+                endLabel: endLabel
+            });
+        }
+        /**
+         * Ends a code block for a generated `with` statement.
+         */
+        function endWithBlock() {
+            ts.Debug.assert(peekBlockKind() === 1 /* With */);
+            var block = endBlock();
+            markLabel(block.endLabel);
+        }
+        /**
+         * Begins a code block for a generated `try` statement.
+         */
+        function beginExceptionBlock() {
+            var startLabel = defineLabel();
+            var endLabel = defineLabel();
+            markLabel(startLabel);
+            beginBlock({
+                kind: 0 /* Exception */,
+                state: 0 /* Try */,
+                startLabel: startLabel,
+                endLabel: endLabel
+            });
+            emitNop();
+            return endLabel;
+        }
+        /**
+         * Enters the `catch` clause of a generated `try` statement.
+         *
+         * @param variable The catch variable.
+         */
+        function beginCatchBlock(variable) {
+            ts.Debug.assert(peekBlockKind() === 0 /* Exception */);
+            // generated identifiers should already be unique within a file
+            var name;
+            if (ts.isGeneratedIdentifier(variable.name)) {
+                name = variable.name;
+                hoistVariableDeclaration(variable.name);
+            }
+            else {
+                var text = ts.idText(variable.name);
+                name = declareLocal(text);
+                if (!renamedCatchVariables) {
+                    renamedCatchVariables = ts.createMap();
+                    renamedCatchVariableDeclarations = [];
+                    context.enableSubstitution(71 /* Identifier */);
+                }
+                renamedCatchVariables.set(text, true);
+                renamedCatchVariableDeclarations[ts.getOriginalNodeId(variable)] = name;
+            }
+            var exception = peekBlock();
+            ts.Debug.assert(exception.state < 1 /* Catch */);
+            var endLabel = exception.endLabel;
+            emitBreak(endLabel);
+            var catchLabel = defineLabel();
+            markLabel(catchLabel);
+            exception.state = 1 /* Catch */;
+            exception.catchVariable = name;
+            exception.catchLabel = catchLabel;
+            emitAssignment(name, ts.createCall(ts.createPropertyAccess(state, "sent"), /*typeArguments*/ undefined, []));
+            emitNop();
+        }
+        /**
+         * Enters the `finally` block of a generated `try` statement.
+         */
+        function beginFinallyBlock() {
+            ts.Debug.assert(peekBlockKind() === 0 /* Exception */);
+            var exception = peekBlock();
+            ts.Debug.assert(exception.state < 2 /* Finally */);
+            var endLabel = exception.endLabel;
+            emitBreak(endLabel);
+            var finallyLabel = defineLabel();
+            markLabel(finallyLabel);
+            exception.state = 2 /* Finally */;
+            exception.finallyLabel = finallyLabel;
+        }
+        /**
+         * Ends the code block for a generated `try` statement.
+         */
+        function endExceptionBlock() {
+            ts.Debug.assert(peekBlockKind() === 0 /* Exception */);
+            var exception = endBlock();
+            var state = exception.state;
+            if (state < 2 /* Finally */) {
+                emitBreak(exception.endLabel);
+            }
+            else {
+                emitEndfinally();
+            }
+            markLabel(exception.endLabel);
+            emitNop();
+            exception.state = 3 /* Done */;
+        }
+        /**
+         * Begins a code block that supports `break` or `continue` statements that are defined in
+         * the source tree and not from generated code.
+         *
+         * @param labelText Names from containing labeled statements.
+         */
+        function beginScriptLoopBlock() {
+            beginBlock({
+                kind: 3 /* Loop */,
+                isScript: true,
+                breakLabel: -1,
+                continueLabel: -1
+            });
+        }
+        /**
+         * Begins a code block that supports `break` or `continue` statements that are defined in
+         * generated code. Returns a label used to mark the operation to which to jump when a
+         * `break` statement targets this block.
+         *
+         * @param continueLabel A Label used to mark the operation to which to jump when a
+         *                      `continue` statement targets this block.
+         */
+        function beginLoopBlock(continueLabel) {
+            var breakLabel = defineLabel();
+            beginBlock({
+                kind: 3 /* Loop */,
+                isScript: false,
+                breakLabel: breakLabel,
+                continueLabel: continueLabel,
+            });
+            return breakLabel;
+        }
+        /**
+         * Ends a code block that supports `break` or `continue` statements that are defined in
+         * generated code or in the source tree.
+         */
+        function endLoopBlock() {
+            ts.Debug.assert(peekBlockKind() === 3 /* Loop */);
+            var block = endBlock();
+            var breakLabel = block.breakLabel;
+            if (!block.isScript) {
+                markLabel(breakLabel);
+            }
+        }
+        /**
+         * Begins a code block that supports `break` statements that are defined in the source
+         * tree and not from generated code.
+         *
+         */
+        function beginScriptSwitchBlock() {
+            beginBlock({
+                kind: 2 /* Switch */,
+                isScript: true,
+                breakLabel: -1
+            });
+        }
+        /**
+         * Begins a code block that supports `break` statements that are defined in generated code.
+         * Returns a label used to mark the operation to which to jump when a `break` statement
+         * targets this block.
+         */
+        function beginSwitchBlock() {
+            var breakLabel = defineLabel();
+            beginBlock({
+                kind: 2 /* Switch */,
+                isScript: false,
+                breakLabel: breakLabel,
+            });
+            return breakLabel;
+        }
+        /**
+         * Ends a code block that supports `break` statements that are defined in generated code.
+         */
+        function endSwitchBlock() {
+            ts.Debug.assert(peekBlockKind() === 2 /* Switch */);
+            var block = endBlock();
+            var breakLabel = block.breakLabel;
+            if (!block.isScript) {
+                markLabel(breakLabel);
+            }
+        }
+        function beginScriptLabeledBlock(labelText) {
+            beginBlock({
+                kind: 4 /* Labeled */,
+                isScript: true,
+                labelText: labelText,
+                breakLabel: -1
+            });
+        }
+        function beginLabeledBlock(labelText) {
+            var breakLabel = defineLabel();
+            beginBlock({
+                kind: 4 /* Labeled */,
+                isScript: false,
+                labelText: labelText,
+                breakLabel: breakLabel
+            });
+        }
+        function endLabeledBlock() {
+            ts.Debug.assert(peekBlockKind() === 4 /* Labeled */);
+            var block = endBlock();
+            if (!block.isScript) {
+                markLabel(block.breakLabel);
+            }
+        }
+        /**
+         * Indicates whether the provided block supports `break` statements.
+         *
+         * @param block A code block.
+         */
+        function supportsUnlabeledBreak(block) {
+            return block.kind === 2 /* Switch */
+                || block.kind === 3 /* Loop */;
+        }
+        /**
+         * Indicates whether the provided block supports `break` statements with labels.
+         *
+         * @param block A code block.
+         */
+        function supportsLabeledBreakOrContinue(block) {
+            return block.kind === 4 /* Labeled */;
+        }
+        /**
+         * Indicates whether the provided block supports `continue` statements.
+         *
+         * @param block A code block.
+         */
+        function supportsUnlabeledContinue(block) {
+            return block.kind === 3 /* Loop */;
+        }
+        function hasImmediateContainingLabeledBlock(labelText, start) {
+            for (var j = start; j >= 0; j--) {
+                var containingBlock = blockStack[j];
+                if (supportsLabeledBreakOrContinue(containingBlock)) {
+                    if (containingBlock.labelText === labelText) {
+                        return true;
+                    }
+                }
+                else {
+                    break;
+                }
+            }
+            return false;
+        }
+        /**
+         * Finds the label that is the target for a `break` statement.
+         *
+         * @param labelText An optional name of a containing labeled statement.
+         */
+        function findBreakTarget(labelText) {
+            if (blockStack) {
+                if (labelText) {
+                    for (var i = blockStack.length - 1; i >= 0; i--) {
+                        var block = blockStack[i];
+                        if (supportsLabeledBreakOrContinue(block) && block.labelText === labelText) {
+                            return block.breakLabel;
+                        }
+                        else if (supportsUnlabeledBreak(block) && hasImmediateContainingLabeledBlock(labelText, i - 1)) {
+                            return block.breakLabel;
+                        }
+                    }
+                }
+                else {
+                    for (var i = blockStack.length - 1; i >= 0; i--) {
+                        var block = blockStack[i];
+                        if (supportsUnlabeledBreak(block)) {
+                            return block.breakLabel;
+                        }
+                    }
+                }
+            }
+            return 0;
+        }
+        /**
+         * Finds the label that is the target for a `continue` statement.
+         *
+         * @param labelText An optional name of a containing labeled statement.
+         */
+        function findContinueTarget(labelText) {
+            if (blockStack) {
+                if (labelText) {
+                    for (var i = blockStack.length - 1; i >= 0; i--) {
+                        var block = blockStack[i];
+                        if (supportsUnlabeledContinue(block) && hasImmediateContainingLabeledBlock(labelText, i - 1)) {
+                            return block.continueLabel;
+                        }
+                    }
+                }
+                else {
+                    for (var i = blockStack.length - 1; i >= 0; i--) {
+                        var block = blockStack[i];
+                        if (supportsUnlabeledContinue(block)) {
+                            return block.continueLabel;
+                        }
+                    }
+                }
+            }
+            return 0;
+        }
+        /**
+         * Creates an expression that can be used to indicate the value for a label.
+         *
+         * @param label A label.
+         */
+        function createLabel(label) {
+            if (label !== undefined && label > 0) {
+                if (labelExpressions === undefined) {
+                    labelExpressions = [];
+                }
+                var expression = ts.createLiteral(-1);
+                if (labelExpressions[label] === undefined) {
+                    labelExpressions[label] = [expression];
+                }
+                else {
+                    labelExpressions[label].push(expression);
+                }
+                return expression;
+            }
+            return ts.createOmittedExpression();
+        }
+        /**
+         * Creates a numeric literal for the provided instruction.
+         */
+        function createInstruction(instruction) {
+            var literal = ts.createLiteral(instruction);
+            ts.addSyntheticTrailingComment(literal, 3 /* MultiLineCommentTrivia */, getInstructionName(instruction));
+            return literal;
+        }
+        /**
+         * Creates a statement that can be used indicate a Break operation to the provided label.
+         *
+         * @param label A label.
+         * @param location An optional source map location for the statement.
+         */
+        function createInlineBreak(label, location) {
+            ts.Debug.assertLessThan(0, label, "Invalid label");
+            return ts.setTextRange(ts.createReturn(ts.createArrayLiteral([
+                createInstruction(3 /* Break */),
+                createLabel(label)
+            ])), location);
+        }
+        /**
+         * Creates a statement that can be used indicate a Return operation.
+         *
+         * @param expression The expression for the return statement.
+         * @param location An optional source map location for the statement.
+         */
+        function createInlineReturn(expression, location) {
+            return ts.setTextRange(ts.createReturn(ts.createArrayLiteral(expression
+                ? [createInstruction(2 /* Return */), expression]
+                : [createInstruction(2 /* Return */)])), location);
+        }
+        /**
+         * Creates an expression that can be used to resume from a Yield operation.
+         */
+        function createGeneratorResume(location) {
+            return ts.setTextRange(ts.createCall(ts.createPropertyAccess(state, "sent"), 
+            /*typeArguments*/ undefined, []), location);
+        }
+        /**
+         * Emits an empty instruction.
+         */
+        function emitNop() {
+            emitWorker(0 /* Nop */);
+        }
+        /**
+         * Emits a Statement.
+         *
+         * @param node A statement.
+         */
+        function emitStatement(node) {
+            if (node) {
+                emitWorker(1 /* Statement */, [node]);
+            }
+            else {
+                emitNop();
+            }
+        }
+        /**
+         * Emits an Assignment operation.
+         *
+         * @param left The left-hand side of the assignment.
+         * @param right The right-hand side of the assignment.
+         * @param location An optional source map location for the assignment.
+         */
+        function emitAssignment(left, right, location) {
+            emitWorker(2 /* Assign */, [left, right], location);
+        }
+        /**
+         * Emits a Break operation to the specified label.
+         *
+         * @param label A label.
+         * @param location An optional source map location for the assignment.
+         */
+        function emitBreak(label, location) {
+            emitWorker(3 /* Break */, [label], location);
+        }
+        /**
+         * Emits a Break operation to the specified label when a condition evaluates to a truthy
+         * value at runtime.
+         *
+         * @param label A label.
+         * @param condition The condition.
+         * @param location An optional source map location for the assignment.
+         */
+        function emitBreakWhenTrue(label, condition, location) {
+            emitWorker(4 /* BreakWhenTrue */, [label, condition], location);
+        }
+        /**
+         * Emits a Break to the specified label when a condition evaluates to a falsey value at
+         * runtime.
+         *
+         * @param label A label.
+         * @param condition The condition.
+         * @param location An optional source map location for the assignment.
+         */
+        function emitBreakWhenFalse(label, condition, location) {
+            emitWorker(5 /* BreakWhenFalse */, [label, condition], location);
+        }
+        /**
+         * Emits a YieldStar operation for the provided expression.
+         *
+         * @param expression An optional value for the yield operation.
+         * @param location An optional source map location for the assignment.
+         */
+        function emitYieldStar(expression, location) {
+            emitWorker(7 /* YieldStar */, [expression], location);
+        }
+        /**
+         * Emits a Yield operation for the provided expression.
+         *
+         * @param expression An optional value for the yield operation.
+         * @param location An optional source map location for the assignment.
+         */
+        function emitYield(expression, location) {
+            emitWorker(6 /* Yield */, [expression], location);
+        }
+        /**
+         * Emits a Return operation for the provided expression.
+         *
+         * @param expression An optional value for the operation.
+         * @param location An optional source map location for the assignment.
+         */
+        function emitReturn(expression, location) {
+            emitWorker(8 /* Return */, [expression], location);
+        }
+        /**
+         * Emits a Throw operation for the provided expression.
+         *
+         * @param expression A value for the operation.
+         * @param location An optional source map location for the assignment.
+         */
+        function emitThrow(expression, location) {
+            emitWorker(9 /* Throw */, [expression], location);
+        }
+        /**
+         * Emits an Endfinally operation. This is used to handle `finally` block semantics.
+         */
+        function emitEndfinally() {
+            emitWorker(10 /* Endfinally */);
+        }
+        /**
+         * Emits an operation.
+         *
+         * @param code The OpCode for the operation.
+         * @param args The optional arguments for the operation.
+         */
+        function emitWorker(code, args, location) {
+            if (operations === undefined) {
+                operations = [];
+                operationArguments = [];
+                operationLocations = [];
+            }
+            if (labelOffsets === undefined) {
+                // mark entry point
+                markLabel(defineLabel());
+            }
+            var operationIndex = operations.length;
+            operations[operationIndex] = code;
+            operationArguments[operationIndex] = args;
+            operationLocations[operationIndex] = location;
+        }
+        /**
+         * Builds the generator function body.
+         */
+        function build() {
+            blockIndex = 0;
+            labelNumber = 0;
+            labelNumbers = undefined;
+            lastOperationWasAbrupt = false;
+            lastOperationWasCompletion = false;
+            clauses = undefined;
+            statements = undefined;
+            exceptionBlockStack = undefined;
+            currentExceptionBlock = undefined;
+            withBlockStack = undefined;
+            var buildResult = buildStatements();
+            return createGeneratorHelper(context, ts.setEmitFlags(ts.createFunctionExpression(
+            /*modifiers*/ undefined, 
+            /*asteriskToken*/ undefined, 
+            /*name*/ undefined, 
+            /*typeParameters*/ undefined, [ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, state)], 
+            /*type*/ undefined, ts.createBlock(buildResult, 
+            /*multiLine*/ buildResult.length > 0)), 524288 /* ReuseTempVariableScope */));
+        }
+        /**
+         * Builds the statements for the generator function body.
+         */
+        function buildStatements() {
+            if (operations) {
+                for (var operationIndex = 0; operationIndex < operations.length; operationIndex++) {
+                    writeOperation(operationIndex);
+                }
+                flushFinalLabel(operations.length);
+            }
+            else {
+                flushFinalLabel(0);
+            }
+            if (clauses) {
+                var labelExpression = ts.createPropertyAccess(state, "label");
+                var switchStatement = ts.createSwitch(labelExpression, ts.createCaseBlock(clauses));
+                return [ts.startOnNewLine(switchStatement)];
+            }
+            if (statements) {
+                return statements;
+            }
+            return [];
+        }
+        /**
+         * Flush the current label and advance to a new label.
+         */
+        function flushLabel() {
+            if (!statements) {
+                return;
+            }
+            appendLabel(/*markLabelEnd*/ !lastOperationWasAbrupt);
+            lastOperationWasAbrupt = false;
+            lastOperationWasCompletion = false;
+            labelNumber++;
+        }
+        /**
+         * Flush the final label of the generator function body.
+         */
+        function flushFinalLabel(operationIndex) {
+            if (isFinalLabelReachable(operationIndex)) {
+                tryEnterLabel(operationIndex);
+                withBlockStack = undefined;
+                writeReturn(/*expression*/ undefined, /*operationLocation*/ undefined);
+            }
+            if (statements && clauses) {
+                appendLabel(/*markLabelEnd*/ false);
+            }
+            updateLabelExpressions();
+        }
+        /**
+         * Tests whether the final label of the generator function body
+         * is reachable by user code.
+         */
+        function isFinalLabelReachable(operationIndex) {
+            // if the last operation was *not* a completion (return/throw) then
+            // the final label is reachable.
+            if (!lastOperationWasCompletion) {
+                return true;
+            }
+            // if there are no labels defined or referenced, then the final label is
+            // not reachable.
+            if (!labelOffsets || !labelExpressions) {
+                return false;
+            }
+            // if the label for this offset is referenced, then the final label
+            // is reachable.
+            for (var label = 0; label < labelOffsets.length; label++) {
+                if (labelOffsets[label] === operationIndex && labelExpressions[label]) {
+                    return true;
+                }
+            }
+            return false;
+        }
+        /**
+         * Appends a case clause for the last label and sets the new label.
+         *
+         * @param markLabelEnd Indicates that the transition between labels was a fall-through
+         *                     from a previous case clause and the change in labels should be
+         *                     reflected on the `state` object.
+         */
+        function appendLabel(markLabelEnd) {
+            if (!clauses) {
+                clauses = [];
+            }
+            if (statements) {
+                if (withBlockStack) {
+                    // The previous label was nested inside one or more `with` blocks, so we
+                    // surround the statements in generated `with` blocks to create the same environment.
+                    for (var i = withBlockStack.length - 1; i >= 0; i--) {
+                        var withBlock = withBlockStack[i];
+                        statements = [ts.createWith(withBlock.expression, ts.createBlock(statements))];
+                    }
+                }
+                if (currentExceptionBlock) {
+                    // The previous label was nested inside of an exception block, so we must
+                    // indicate entry into a protected region by pushing the label numbers
+                    // for each block in the protected region.
+                    var startLabel = currentExceptionBlock.startLabel, catchLabel = currentExceptionBlock.catchLabel, finallyLabel = currentExceptionBlock.finallyLabel, endLabel = currentExceptionBlock.endLabel;
+                    statements.unshift(ts.createStatement(ts.createCall(ts.createPropertyAccess(ts.createPropertyAccess(state, "trys"), "push"), 
+                    /*typeArguments*/ undefined, [
+                        ts.createArrayLiteral([
+                            createLabel(startLabel),
+                            createLabel(catchLabel),
+                            createLabel(finallyLabel),
+                            createLabel(endLabel)
+                        ])
+                    ])));
+                    currentExceptionBlock = undefined;
+                }
+                if (markLabelEnd) {
+                    // The case clause for the last label falls through to this label, so we
+                    // add an assignment statement to reflect the change in labels.
+                    statements.push(ts.createStatement(ts.createAssignment(ts.createPropertyAccess(state, "label"), ts.createLiteral(labelNumber + 1))));
+                }
+            }
+            clauses.push(ts.createCaseClause(ts.createLiteral(labelNumber), statements || []));
+            statements = undefined;
+        }
+        /**
+         * Tries to enter into a new label at the current operation index.
+         */
+        function tryEnterLabel(operationIndex) {
+            if (!labelOffsets) {
+                return;
+            }
+            for (var label = 0; label < labelOffsets.length; label++) {
+                if (labelOffsets[label] === operationIndex) {
+                    flushLabel();
+                    if (labelNumbers === undefined) {
+                        labelNumbers = [];
+                    }
+                    if (labelNumbers[labelNumber] === undefined) {
+                        labelNumbers[labelNumber] = [label];
+                    }
+                    else {
+                        labelNumbers[labelNumber].push(label);
+                    }
+                }
+            }
+        }
+        /**
+         * Updates literal expressions for labels with actual label numbers.
+         */
+        function updateLabelExpressions() {
+            if (labelExpressions !== undefined && labelNumbers !== undefined) {
+                for (var labelNumber_1 = 0; labelNumber_1 < labelNumbers.length; labelNumber_1++) {
+                    var labels = labelNumbers[labelNumber_1];
+                    if (labels !== undefined) {
+                        for (var _i = 0, labels_1 = labels; _i < labels_1.length; _i++) {
+                            var label = labels_1[_i];
+                            var expressions = labelExpressions[label];
+                            if (expressions !== undefined) {
+                                for (var _a = 0, expressions_1 = expressions; _a < expressions_1.length; _a++) {
+                                    var expression = expressions_1[_a];
+                                    expression.text = String(labelNumber_1);
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        /**
+         * Tries to enter or leave a code block.
+         */
+        function tryEnterOrLeaveBlock(operationIndex) {
+            if (blocks) {
+                for (; blockIndex < blockActions.length && blockOffsets[blockIndex] <= operationIndex; blockIndex++) {
+                    var block = blocks[blockIndex];
+                    var blockAction = blockActions[blockIndex];
+                    switch (block.kind) {
+                        case 0 /* Exception */:
+                            if (blockAction === 0 /* Open */) {
+                                if (!exceptionBlockStack) {
+                                    exceptionBlockStack = [];
+                                }
+                                if (!statements) {
+                                    statements = [];
+                                }
+                                exceptionBlockStack.push(currentExceptionBlock);
+                                currentExceptionBlock = block;
+                            }
+                            else if (blockAction === 1 /* Close */) {
+                                currentExceptionBlock = exceptionBlockStack.pop();
+                            }
+                            break;
+                        case 1 /* With */:
+                            if (blockAction === 0 /* Open */) {
+                                if (!withBlockStack) {
+                                    withBlockStack = [];
+                                }
+                                withBlockStack.push(block);
+                            }
+                            else if (blockAction === 1 /* Close */) {
+                                withBlockStack.pop();
+                            }
+                            break;
+                        // default: do nothing
+                    }
+                }
+            }
+        }
+        /**
+         * Writes an operation as a statement to the current label's statement list.
+         *
+         * @param operation The OpCode of the operation
+         */
+        function writeOperation(operationIndex) {
+            tryEnterLabel(operationIndex);
+            tryEnterOrLeaveBlock(operationIndex);
+            // early termination, nothing else to process in this label
+            if (lastOperationWasAbrupt) {
+                return;
+            }
+            lastOperationWasAbrupt = false;
+            lastOperationWasCompletion = false;
+            var opcode = operations[operationIndex];
+            if (opcode === 0 /* Nop */) {
+                return;
+            }
+            else if (opcode === 10 /* Endfinally */) {
+                return writeEndfinally();
+            }
+            var args = operationArguments[operationIndex];
+            if (opcode === 1 /* Statement */) {
+                return writeStatement(args[0]);
+            }
+            var location = operationLocations[operationIndex];
+            switch (opcode) {
+                case 2 /* Assign */:
+                    return writeAssign(args[0], args[1], location);
+                case 3 /* Break */:
+                    return writeBreak(args[0], location);
+                case 4 /* BreakWhenTrue */:
+                    return writeBreakWhenTrue(args[0], args[1], location);
+                case 5 /* BreakWhenFalse */:
+                    return writeBreakWhenFalse(args[0], args[1], location);
+                case 6 /* Yield */:
+                    return writeYield(args[0], location);
+                case 7 /* YieldStar */:
+                    return writeYieldStar(args[0], location);
+                case 8 /* Return */:
+                    return writeReturn(args[0], location);
+                case 9 /* Throw */:
+                    return writeThrow(args[0], location);
+            }
+        }
+        /**
+         * Writes a statement to the current label's statement list.
+         *
+         * @param statement A statement to write.
+         */
+        function writeStatement(statement) {
+            if (statement) {
+                if (!statements) {
+                    statements = [statement];
+                }
+                else {
+                    statements.push(statement);
+                }
+            }
+        }
+        /**
+         * Writes an Assign operation to the current label's statement list.
+         *
+         * @param left The left-hand side of the assignment.
+         * @param right The right-hand side of the assignment.
+         * @param operationLocation The source map location for the operation.
+         */
+        function writeAssign(left, right, operationLocation) {
+            writeStatement(ts.setTextRange(ts.createStatement(ts.createAssignment(left, right)), operationLocation));
+        }
+        /**
+         * Writes a Throw operation to the current label's statement list.
+         *
+         * @param expression The value to throw.
+         * @param operationLocation The source map location for the operation.
+         */
+        function writeThrow(expression, operationLocation) {
+            lastOperationWasAbrupt = true;
+            lastOperationWasCompletion = true;
+            writeStatement(ts.setTextRange(ts.createThrow(expression), operationLocation));
+        }
+        /**
+         * Writes a Return operation to the current label's statement list.
+         *
+         * @param expression The value to return.
+         * @param operationLocation The source map location for the operation.
+         */
+        function writeReturn(expression, operationLocation) {
+            lastOperationWasAbrupt = true;
+            lastOperationWasCompletion = true;
+            writeStatement(ts.setEmitFlags(ts.setTextRange(ts.createReturn(ts.createArrayLiteral(expression
+                ? [createInstruction(2 /* Return */), expression]
+                : [createInstruction(2 /* Return */)])), operationLocation), 384 /* NoTokenSourceMaps */));
+        }
+        /**
+         * Writes a Break operation to the current label's statement list.
+         *
+         * @param label The label for the Break.
+         * @param operationLocation The source map location for the operation.
+         */
+        function writeBreak(label, operationLocation) {
+            lastOperationWasAbrupt = true;
+            writeStatement(ts.setEmitFlags(ts.setTextRange(ts.createReturn(ts.createArrayLiteral([
+                createInstruction(3 /* Break */),
+                createLabel(label)
+            ])), operationLocation), 384 /* NoTokenSourceMaps */));
+        }
+        /**
+         * Writes a BreakWhenTrue operation to the current label's statement list.
+         *
+         * @param label The label for the Break.
+         * @param condition The condition for the Break.
+         * @param operationLocation The source map location for the operation.
+         */
+        function writeBreakWhenTrue(label, condition, operationLocation) {
+            writeStatement(ts.setEmitFlags(ts.createIf(condition, ts.setEmitFlags(ts.setTextRange(ts.createReturn(ts.createArrayLiteral([
+                createInstruction(3 /* Break */),
+                createLabel(label)
+            ])), operationLocation), 384 /* NoTokenSourceMaps */)), 1 /* SingleLine */));
+        }
+        /**
+         * Writes a BreakWhenFalse operation to the current label's statement list.
+         *
+         * @param label The label for the Break.
+         * @param condition The condition for the Break.
+         * @param operationLocation The source map location for the operation.
+         */
+        function writeBreakWhenFalse(label, condition, operationLocation) {
+            writeStatement(ts.setEmitFlags(ts.createIf(ts.createLogicalNot(condition), ts.setEmitFlags(ts.setTextRange(ts.createReturn(ts.createArrayLiteral([
+                createInstruction(3 /* Break */),
+                createLabel(label)
+            ])), operationLocation), 384 /* NoTokenSourceMaps */)), 1 /* SingleLine */));
+        }
+        /**
+         * Writes a Yield operation to the current label's statement list.
+         *
+         * @param expression The expression to yield.
+         * @param operationLocation The source map location for the operation.
+         */
+        function writeYield(expression, operationLocation) {
+            lastOperationWasAbrupt = true;
+            writeStatement(ts.setEmitFlags(ts.setTextRange(ts.createReturn(ts.createArrayLiteral(expression
+                ? [createInstruction(4 /* Yield */), expression]
+                : [createInstruction(4 /* Yield */)])), operationLocation), 384 /* NoTokenSourceMaps */));
+        }
+        /**
+         * Writes a YieldStar instruction to the current label's statement list.
+         *
+         * @param expression The expression to yield.
+         * @param operationLocation The source map location for the operation.
+         */
+        function writeYieldStar(expression, operationLocation) {
+            lastOperationWasAbrupt = true;
+            writeStatement(ts.setEmitFlags(ts.setTextRange(ts.createReturn(ts.createArrayLiteral([
+                createInstruction(5 /* YieldStar */),
+                expression
+            ])), operationLocation), 384 /* NoTokenSourceMaps */));
+        }
+        /**
+         * Writes an Endfinally instruction to the current label's statement list.
+         */
+        function writeEndfinally() {
+            lastOperationWasAbrupt = true;
+            writeStatement(ts.createReturn(ts.createArrayLiteral([
+                createInstruction(7 /* Endfinally */)
+            ])));
+        }
+    }
+    ts.transformGenerators = transformGenerators;
+    function createGeneratorHelper(context, body) {
+        context.requestEmitHelper(generatorHelper);
+        return ts.createCall(ts.getHelperName("__generator"), 
+        /*typeArguments*/ undefined, [ts.createThis(), body]);
+    }
+    // The __generator helper is used by down-level transformations to emulate the runtime
+    // semantics of an ES2015 generator function. When called, this helper returns an
+    // object that implements the Iterator protocol, in that it has `next`, `return`, and
+    // `throw` methods that step through the generator when invoked.
+    //
+    // parameters:
+    //  @param thisArg  The value to use as the `this` binding for the transformed generator body.
+    //  @param body     A function that acts as the transformed generator body.
+    //
+    // variables:
+    //  _       Persistent state for the generator that is shared between the helper and the
+    //          generator body. The state object has the following members:
+    //            sent() - A method that returns or throws the current completion value.
+    //            label  - The next point at which to resume evaluation of the generator body.
+    //            trys   - A stack of protected regions (try/catch/finally blocks).
+    //            ops    - A stack of pending instructions when inside of a finally block.
+    //  f       A value indicating whether the generator is executing.
+    //  y       An iterator to delegate for a yield*.
+    //  t       A temporary variable that holds one of the following values (note that these
+    //          cases do not overlap):
+    //          - The completion value when resuming from a `yield` or `yield*`.
+    //          - The error value for a catch block.
+    //          - The current protected region (array of try/catch/finally/end labels).
+    //          - The verb (`next`, `throw`, or `return` method) to delegate to the expression
+    //            of a `yield*`.
+    //          - The result of evaluating the verb delegated to the expression of a `yield*`.
+    //
+    // functions:
+    //  verb(n)     Creates a bound callback to the `step` function for opcode `n`.
+    //  step(op)    Evaluates opcodes in a generator body until execution is suspended or
+    //              completed.
+    //
+    // The __generator helper understands a limited set of instructions:
+    //  0: next(value?)     - Start or resume the generator with the specified value.
+    //  1: throw(error)     - Resume the generator with an exception. If the generator is
+    //                        suspended inside of one or more protected regions, evaluates
+    //                        any intervening finally blocks between the current label and
+    //                        the nearest catch block or function boundary. If uncaught, the
+    //                        exception is thrown to the caller.
+    //  2: return(value?)   - Resume the generator as if with a return. If the generator is
+    //                        suspended inside of one or more protected regions, evaluates any
+    //                        intervening finally blocks.
+    //  3: break(label)     - Jump to the specified label. If the label is outside of the
+    //                        current protected region, evaluates any intervening finally
+    //                        blocks.
+    //  4: yield(value?)    - Yield execution to the caller with an optional value. When
+    //                        resumed, the generator will continue at the next label.
+    //  5: yield*(value)    - Delegates evaluation to the supplied iterator. When
+    //                        delegation completes, the generator will continue at the next
+    //                        label.
+    //  6: catch(error)     - Handles an exception thrown from within the generator body. If
+    //                        the current label is inside of one or more protected regions,
+    //                        evaluates any intervening finally blocks between the current
+    //                        label and the nearest catch block or function boundary. If
+    //                        uncaught, the exception is thrown to the caller.
+    //  7: endfinally       - Ends a finally block, resuming the last instruction prior to
+    //                        entering a finally block.
+    //
+    // For examples of how these are used, see the comments in ./transformers/generators.ts
+    var generatorHelper = {
+        name: "typescript:generator",
+        scoped: false,
+        priority: 6,
+        text: "\n            var __generator = (this && this.__generator) || function (thisArg, body) {\n                var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t, g;\n                return g = { next: verb(0), \"throw\": verb(1), \"return\": verb(2) }, typeof Symbol === \"function\" && (g[Symbol.iterator] = function() { return this; }), g;\n                function verb(n) { return function (v) { return step([n, v]); }; }\n                function step(op) {\n                    if (f) throw new TypeError(\"Generator is already executing.\");\n                    while (_) try {\n                        if (f = 1, y && (t = op[0] & 2 ? y[\"return\"] : op[0] ? y[\"throw\"] || ((t = y[\"return\"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;\n                        if (y = 0, t) op = [op[0] & 2, t.value];\n                        switch (op[0]) {\n                            case 0: case 1: t = op; break;\n                            case 4: _.label++; return { value: op[1], done: false };\n                            case 5: _.label++; y = op[1]; op = [0]; continue;\n                            case 7: op = _.ops.pop(); _.trys.pop(); continue;\n                            default:\n                                if (!(t = _.trys, t = t.length > 0 && t[t.length - 1]) && (op[0] === 6 || op[0] === 2)) { _ = 0; continue; }\n                                if (op[0] === 3 && (!t || (op[1] > t[0] && op[1] < t[3]))) { _.label = op[1]; break; }\n                                if (op[0] === 6 && _.label < t[1]) { _.label = t[1]; t = op; break; }\n                                if (t && _.label < t[2]) { _.label = t[2]; _.ops.push(op); break; }\n                                if (t[2]) _.ops.pop();\n                                _.trys.pop(); continue;\n                        }\n                        op = body.call(thisArg, _);\n                    } catch (e) { op = [6, e]; y = 0; } finally { f = t = 0; }\n                    if (op[0] & 5) throw op[1]; return { value: op[0] ? op[1] : void 0, done: true };\n                }\n            };"
+    };
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    function transformModule(context) {
+        function getTransformModuleDelegate(moduleKind) {
+            switch (moduleKind) {
+                case ts.ModuleKind.AMD: return transformAMDModule;
+                case ts.ModuleKind.UMD: return transformUMDModule;
+                default: return transformCommonJSModule;
+            }
+        }
+        var startLexicalEnvironment = context.startLexicalEnvironment, endLexicalEnvironment = context.endLexicalEnvironment, hoistVariableDeclaration = context.hoistVariableDeclaration;
+        var compilerOptions = context.getCompilerOptions();
+        var resolver = context.getEmitResolver();
+        var host = context.getEmitHost();
+        var languageVersion = ts.getEmitScriptTarget(compilerOptions);
+        var moduleKind = ts.getEmitModuleKind(compilerOptions);
+        var previousOnSubstituteNode = context.onSubstituteNode;
+        var previousOnEmitNode = context.onEmitNode;
+        context.onSubstituteNode = onSubstituteNode;
+        context.onEmitNode = onEmitNode;
+        context.enableSubstitution(71 /* Identifier */); // Substitutes expression identifiers with imported/exported symbols.
+        context.enableSubstitution(200 /* BinaryExpression */); // Substitutes assignments to exported symbols.
+        context.enableSubstitution(198 /* PrefixUnaryExpression */); // Substitutes updates to exported symbols.
+        context.enableSubstitution(199 /* PostfixUnaryExpression */); // Substitutes updates to exported symbols.
+        context.enableSubstitution(271 /* ShorthandPropertyAssignment */); // Substitutes shorthand property assignments for imported/exported symbols.
+        context.enableEmitNotification(274 /* SourceFile */); // Restore state when substituting nodes in a file.
+        var moduleInfoMap = []; // The ExternalModuleInfo for each file.
+        var deferredExports = []; // Exports to defer until an EndOfDeclarationMarker is found.
+        var currentSourceFile; // The current file.
+        var currentModuleInfo; // The ExternalModuleInfo for the current file.
+        var noSubstitution; // Set of nodes for which substitution rules should be ignored.
+        var needUMDDynamicImportHelper;
+        return ts.chainBundle(transformSourceFile);
+        /**
+         * Transforms the module aspects of a SourceFile.
+         *
+         * @param node The SourceFile node.
+         */
+        function transformSourceFile(node) {
+            if (node.isDeclarationFile || !(ts.isEffectiveExternalModule(node, compilerOptions) || node.transformFlags & 67108864 /* ContainsDynamicImport */)) {
+                return node;
+            }
+            currentSourceFile = node;
+            currentModuleInfo = ts.collectExternalModuleInfo(node, resolver, compilerOptions);
+            moduleInfoMap[ts.getOriginalNodeId(node)] = currentModuleInfo;
+            // Perform the transformation.
+            var transformModule = getTransformModuleDelegate(moduleKind);
+            var updated = transformModule(node);
+            currentSourceFile = undefined;
+            currentModuleInfo = undefined;
+            needUMDDynamicImportHelper = false;
+            return ts.aggregateTransformFlags(updated);
+        }
+        function shouldEmitUnderscoreUnderscoreESModule() {
+            if (!currentModuleInfo.exportEquals && ts.isExternalModule(currentSourceFile)) {
+                return true;
+            }
+            return false;
+        }
+        /**
+         * Transforms a SourceFile into a CommonJS module.
+         *
+         * @param node The SourceFile node.
+         */
+        function transformCommonJSModule(node) {
+            startLexicalEnvironment();
+            var statements = [];
+            var ensureUseStrict = ts.getStrictOptionValue(compilerOptions, "alwaysStrict") || (!compilerOptions.noImplicitUseStrict && ts.isExternalModule(currentSourceFile));
+            var statementOffset = ts.addPrologue(statements, node.statements, ensureUseStrict, sourceElementVisitor);
+            if (shouldEmitUnderscoreUnderscoreESModule()) {
+                ts.append(statements, createUnderscoreUnderscoreESModule());
+            }
+            ts.append(statements, ts.visitNode(currentModuleInfo.externalHelpersImportDeclaration, sourceElementVisitor, ts.isStatement));
+            ts.addRange(statements, ts.visitNodes(node.statements, sourceElementVisitor, ts.isStatement, statementOffset));
+            addExportEqualsIfNeeded(statements, /*emitAsReturn*/ false);
+            ts.prependStatements(statements, endLexicalEnvironment());
+            var updated = ts.updateSourceFileNode(node, ts.setTextRange(ts.createNodeArray(statements), node.statements));
+            if (currentModuleInfo.hasExportStarsToExportValues && !compilerOptions.importHelpers) {
+                // If we have any `export * from ...` declarations
+                // we need to inform the emitter to add the __export helper.
+                ts.addEmitHelper(updated, exportStarHelper);
+            }
+            ts.addEmitHelpers(updated, context.readEmitHelpers());
+            return updated;
+        }
+        /**
+         * Transforms a SourceFile into an AMD module.
+         *
+         * @param node The SourceFile node.
+         */
+        function transformAMDModule(node) {
+            var define = ts.createIdentifier("define");
+            var moduleName = ts.tryGetModuleNameFromFile(node, host, compilerOptions);
+            // An AMD define function has the following shape:
+            //
+            //     define(id?, dependencies?, factory);
+            //
+            // This has the shape of the following:
+            //
+            //     define(name, ["module1", "module2"], function (module1Alias) { ... }
+            //
+            // The location of the alias in the parameter list in the factory function needs to
+            // match the position of the module name in the dependency list.
+            //
+            // To ensure this is true in cases of modules with no aliases, e.g.:
+            //
+            //     import "module"
+            //
+            // or
+            //
+            //     /// <amd-dependency path= "a.css" />
+            //
+            // we need to add modules without alias names to the end of the dependencies list
+            var _a = collectAsynchronousDependencies(node, /*includeNonAmdDependencies*/ true), aliasedModuleNames = _a.aliasedModuleNames, unaliasedModuleNames = _a.unaliasedModuleNames, importAliasNames = _a.importAliasNames;
+            // Create an updated SourceFile:
+            //
+            //     define(moduleName?, ["module1", "module2"], function ...
+            var updated = ts.updateSourceFileNode(node, ts.setTextRange(ts.createNodeArray([
+                ts.createStatement(ts.createCall(define, 
+                /*typeArguments*/ undefined, (moduleName ? [moduleName] : []).concat([
+                    // Add the dependency array argument:
+                    //
+                    //     ["require", "exports", module1", "module2", ...]
+                    ts.createArrayLiteral([
+                        ts.createLiteral("require"),
+                        ts.createLiteral("exports")
+                    ].concat(aliasedModuleNames, unaliasedModuleNames)),
+                    // Add the module body function argument:
+                    //
+                    //     function (require, exports, module1, module2) ...
+                    ts.createFunctionExpression(
+                    /*modifiers*/ undefined, 
+                    /*asteriskToken*/ undefined, 
+                    /*name*/ undefined, 
+                    /*typeParameters*/ undefined, [
+                        ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, "require"),
+                        ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, "exports")
+                    ].concat(importAliasNames), 
+                    /*type*/ undefined, transformAsynchronousModuleBody(node))
+                ])))
+            ]), 
+            /*location*/ node.statements));
+            ts.addEmitHelpers(updated, context.readEmitHelpers());
+            return updated;
+        }
+        /**
+         * Transforms a SourceFile into a UMD module.
+         *
+         * @param node The SourceFile node.
+         */
+        function transformUMDModule(node) {
+            var _a = collectAsynchronousDependencies(node, /*includeNonAmdDependencies*/ false), aliasedModuleNames = _a.aliasedModuleNames, unaliasedModuleNames = _a.unaliasedModuleNames, importAliasNames = _a.importAliasNames;
+            var moduleName = ts.tryGetModuleNameFromFile(node, host, compilerOptions);
+            var umdHeader = ts.createFunctionExpression(
+            /*modifiers*/ undefined, 
+            /*asteriskToken*/ undefined, 
+            /*name*/ undefined, 
+            /*typeParameters*/ undefined, [ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, "factory")], 
+            /*type*/ undefined, ts.setTextRange(ts.createBlock([
+                ts.createIf(ts.createLogicalAnd(ts.createTypeCheck(ts.createIdentifier("module"), "object"), ts.createTypeCheck(ts.createPropertyAccess(ts.createIdentifier("module"), "exports"), "object")), ts.createBlock([
+                    ts.createVariableStatement(
+                    /*modifiers*/ undefined, [
+                        ts.createVariableDeclaration("v", 
+                        /*type*/ undefined, ts.createCall(ts.createIdentifier("factory"), 
+                        /*typeArguments*/ undefined, [
+                            ts.createIdentifier("require"),
+                            ts.createIdentifier("exports")
+                        ]))
+                    ]),
+                    ts.setEmitFlags(ts.createIf(ts.createStrictInequality(ts.createIdentifier("v"), ts.createIdentifier("undefined")), ts.createStatement(ts.createAssignment(ts.createPropertyAccess(ts.createIdentifier("module"), "exports"), ts.createIdentifier("v")))), 1 /* SingleLine */)
+                ]), ts.createIf(ts.createLogicalAnd(ts.createTypeCheck(ts.createIdentifier("define"), "function"), ts.createPropertyAccess(ts.createIdentifier("define"), "amd")), ts.createBlock([
+                    ts.createStatement(ts.createCall(ts.createIdentifier("define"), 
+                    /*typeArguments*/ undefined, (moduleName ? [moduleName] : []).concat([
+                        ts.createArrayLiteral([
+                            ts.createLiteral("require"),
+                            ts.createLiteral("exports")
+                        ].concat(aliasedModuleNames, unaliasedModuleNames)),
+                        ts.createIdentifier("factory")
+                    ])))
+                ])))
+            ], 
+            /*multiLine*/ true), 
+            /*location*/ undefined));
+            // Create an updated SourceFile:
+            //
+            //  (function (factory) {
+            //      if (typeof module === "object" && typeof module.exports === "object") {
+            //          var v = factory(require, exports);
+            //          if (v !== undefined) module.exports = v;
+            //      }
+            //      else if (typeof define === 'function' && define.amd) {
+            //          define(["require", "exports"], factory);
+            //      }
+            //  })(function ...)
+            var updated = ts.updateSourceFileNode(node, ts.setTextRange(ts.createNodeArray([
+                ts.createStatement(ts.createCall(umdHeader, 
+                /*typeArguments*/ undefined, [
+                    // Add the module body function argument:
+                    //
+                    //     function (require, exports) ...
+                    ts.createFunctionExpression(
+                    /*modifiers*/ undefined, 
+                    /*asteriskToken*/ undefined, 
+                    /*name*/ undefined, 
+                    /*typeParameters*/ undefined, [
+                        ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, "require"),
+                        ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, "exports")
+                    ].concat(importAliasNames), 
+                    /*type*/ undefined, transformAsynchronousModuleBody(node))
+                ]))
+            ]), 
+            /*location*/ node.statements));
+            ts.addEmitHelpers(updated, context.readEmitHelpers());
+            return updated;
+        }
+        /**
+         * Collect the additional asynchronous dependencies for the module.
+         *
+         * @param node The source file.
+         * @param includeNonAmdDependencies A value indicating whether to include non-AMD dependencies.
+         */
+        function collectAsynchronousDependencies(node, includeNonAmdDependencies) {
+            // names of modules with corresponding parameter in the factory function
+            var aliasedModuleNames = [];
+            // names of modules with no corresponding parameters in factory function
+            var unaliasedModuleNames = [];
+            // names of the parameters in the factory function; these
+            // parameters need to match the indexes of the corresponding
+            // module names in aliasedModuleNames.
+            var importAliasNames = [];
+            // Fill in amd-dependency tags
+            for (var _i = 0, _a = node.amdDependencies; _i < _a.length; _i++) {
+                var amdDependency = _a[_i];
+                if (amdDependency.name) {
+                    aliasedModuleNames.push(ts.createLiteral(amdDependency.path));
+                    importAliasNames.push(ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, amdDependency.name));
+                }
+                else {
+                    unaliasedModuleNames.push(ts.createLiteral(amdDependency.path));
+                }
+            }
+            for (var _b = 0, _c = currentModuleInfo.externalImports; _b < _c.length; _b++) {
+                var importNode = _c[_b];
+                // Find the name of the external module
+                var externalModuleName = ts.getExternalModuleNameLiteral(importNode, currentSourceFile, host, resolver, compilerOptions);
+                // Find the name of the module alias, if there is one
+                var importAliasName = ts.getLocalNameForExternalImport(importNode, currentSourceFile);
+                // It is possible that externalModuleName is undefined if it is not string literal.
+                // This can happen in the invalid import syntax.
+                // E.g : "import * from alias from 'someLib';"
+                if (externalModuleName) {
+                    if (includeNonAmdDependencies && importAliasName) {
+                        // Set emitFlags on the name of the classDeclaration
+                        // This is so that when printer will not substitute the identifier
+                        ts.setEmitFlags(importAliasName, 4 /* NoSubstitution */);
+                        aliasedModuleNames.push(externalModuleName);
+                        importAliasNames.push(ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, importAliasName));
+                    }
+                    else {
+                        unaliasedModuleNames.push(externalModuleName);
+                    }
+                }
+            }
+            return { aliasedModuleNames: aliasedModuleNames, unaliasedModuleNames: unaliasedModuleNames, importAliasNames: importAliasNames };
+        }
+        function getAMDImportExpressionForImport(node) {
+            if (ts.isImportEqualsDeclaration(node) || ts.isExportDeclaration(node) || !ts.getExternalModuleNameLiteral(node, currentSourceFile, host, resolver, compilerOptions)) {
+                return undefined;
+            }
+            var name = ts.getLocalNameForExternalImport(node, currentSourceFile); // TODO: GH#18217
+            var expr = getHelperExpressionForImport(node, name);
+            if (expr === name) {
+                return undefined;
+            }
+            return ts.createStatement(ts.createAssignment(name, expr));
+        }
+        /**
+         * Transforms a SourceFile into an AMD or UMD module body.
+         *
+         * @param node The SourceFile node.
+         */
+        function transformAsynchronousModuleBody(node) {
+            startLexicalEnvironment();
+            var statements = [];
+            var statementOffset = ts.addPrologue(statements, node.statements, /*ensureUseStrict*/ !compilerOptions.noImplicitUseStrict, sourceElementVisitor);
+            if (shouldEmitUnderscoreUnderscoreESModule()) {
+                ts.append(statements, createUnderscoreUnderscoreESModule());
+            }
+            // Visit each statement of the module body.
+            ts.append(statements, ts.visitNode(currentModuleInfo.externalHelpersImportDeclaration, sourceElementVisitor, ts.isStatement));
+            if (moduleKind === ts.ModuleKind.AMD) {
+                ts.addRange(statements, ts.mapDefined(currentModuleInfo.externalImports, getAMDImportExpressionForImport));
+            }
+            ts.addRange(statements, ts.visitNodes(node.statements, sourceElementVisitor, ts.isStatement, statementOffset));
+            // Append the 'export =' statement if provided.
+            addExportEqualsIfNeeded(statements, /*emitAsReturn*/ true);
+            // End the lexical environment for the module body
+            // and merge any new lexical declarations.
+            ts.prependStatements(statements, endLexicalEnvironment());
+            var body = ts.createBlock(statements, /*multiLine*/ true);
+            if (currentModuleInfo.hasExportStarsToExportValues && !compilerOptions.importHelpers) {
+                // If we have any `export * from ...` declarations
+                // we need to inform the emitter to add the __export helper.
+                ts.addEmitHelper(body, exportStarHelper);
+            }
+            if (needUMDDynamicImportHelper) {
+                ts.addEmitHelper(body, dynamicImportUMDHelper);
+            }
+            return body;
+        }
+        /**
+         * Adds the down-level representation of `export=` to the statement list if one exists
+         * in the source file.
+         *
+         * @param statements The Statement list to modify.
+         * @param emitAsReturn A value indicating whether to emit the `export=` statement as a
+         * return statement.
+         */
+        function addExportEqualsIfNeeded(statements, emitAsReturn) {
+            if (currentModuleInfo.exportEquals) {
+                var expressionResult = ts.visitNode(currentModuleInfo.exportEquals.expression, moduleExpressionElementVisitor);
+                if (expressionResult) {
+                    if (emitAsReturn) {
+                        var statement = ts.createReturn(expressionResult);
+                        ts.setTextRange(statement, currentModuleInfo.exportEquals);
+                        ts.setEmitFlags(statement, 384 /* NoTokenSourceMaps */ | 1536 /* NoComments */);
+                        statements.push(statement);
+                    }
+                    else {
+                        var statement = ts.createStatement(ts.createAssignment(ts.createPropertyAccess(ts.createIdentifier("module"), "exports"), expressionResult));
+                        ts.setTextRange(statement, currentModuleInfo.exportEquals);
+                        ts.setEmitFlags(statement, 1536 /* NoComments */);
+                        statements.push(statement);
+                    }
+                }
+            }
+        }
+        //
+        // Top-Level Source Element Visitors
+        //
+        /**
+         * Visits a node at the top level of the source file.
+         *
+         * @param node The node to visit.
+         */
+        function sourceElementVisitor(node) {
+            switch (node.kind) {
+                case 244 /* ImportDeclaration */:
+                    return visitImportDeclaration(node);
+                case 243 /* ImportEqualsDeclaration */:
+                    return visitImportEqualsDeclaration(node);
+                case 250 /* ExportDeclaration */:
+                    return visitExportDeclaration(node);
+                case 249 /* ExportAssignment */:
+                    return visitExportAssignment(node);
+                case 214 /* VariableStatement */:
+                    return visitVariableStatement(node);
+                case 234 /* FunctionDeclaration */:
+                    return visitFunctionDeclaration(node);
+                case 235 /* ClassDeclaration */:
+                    return visitClassDeclaration(node);
+                case 303 /* MergeDeclarationMarker */:
+                    return visitMergeDeclarationMarker(node);
+                case 304 /* EndOfDeclarationMarker */:
+                    return visitEndOfDeclarationMarker(node);
+                default:
+                    return ts.visitEachChild(node, moduleExpressionElementVisitor, context);
+            }
+        }
+        function moduleExpressionElementVisitor(node) {
+            // This visitor does not need to descend into the tree if there is no dynamic import or destructuring assignment,
+            // as export/import statements are only transformed at the top level of a file.
+            if (!(node.transformFlags & 67108864 /* ContainsDynamicImport */) && !(node.transformFlags & 2048 /* ContainsDestructuringAssignment */)) {
+                return node;
+            }
+            if (ts.isImportCall(node)) {
+                return visitImportCallExpression(node);
+            }
+            else if (node.transformFlags & 1024 /* DestructuringAssignment */ && ts.isBinaryExpression(node)) {
+                return visitDestructuringAssignment(node);
+            }
+            else {
+                return ts.visitEachChild(node, moduleExpressionElementVisitor, context);
+            }
+        }
+        function destructuringNeedsFlattening(node) {
+            if (ts.isObjectLiteralExpression(node)) {
+                for (var _i = 0, _a = node.properties; _i < _a.length; _i++) {
+                    var elem = _a[_i];
+                    switch (elem.kind) {
+                        case 270 /* PropertyAssignment */:
+                            if (destructuringNeedsFlattening(elem.initializer)) {
+                                return true;
+                            }
+                            break;
+                        case 271 /* ShorthandPropertyAssignment */:
+                            if (destructuringNeedsFlattening(elem.name)) {
+                                return true;
+                            }
+                            break;
+                        case 272 /* SpreadAssignment */:
+                            if (destructuringNeedsFlattening(elem.expression)) {
+                                return true;
+                            }
+                            break;
+                        case 154 /* MethodDeclaration */:
+                        case 156 /* GetAccessor */:
+                        case 157 /* SetAccessor */:
+                            return false;
+                        default: ts.Debug.assertNever(elem, "Unhandled object member kind");
+                    }
+                }
+            }
+            else if (ts.isArrayLiteralExpression(node)) {
+                for (var _b = 0, _c = node.elements; _b < _c.length; _b++) {
+                    var elem = _c[_b];
+                    if (ts.isSpreadElement(elem)) {
+                        if (destructuringNeedsFlattening(elem.expression)) {
+                            return true;
+                        }
+                    }
+                    else if (destructuringNeedsFlattening(elem)) {
+                        return true;
+                    }
+                }
+            }
+            else if (ts.isIdentifier(node)) {
+                return ts.length(getExports(node)) > (ts.isExportName(node) ? 1 : 0);
+            }
+            return false;
+        }
+        function visitDestructuringAssignment(node) {
+            if (destructuringNeedsFlattening(node.left)) {
+                return ts.flattenDestructuringAssignment(node, moduleExpressionElementVisitor, context, 0 /* All */, /*needsValue*/ false, createAllExportExpressions);
+            }
+            return ts.visitEachChild(node, moduleExpressionElementVisitor, context);
+        }
+        function visitImportCallExpression(node) {
+            var argument = ts.visitNode(ts.firstOrUndefined(node.arguments), moduleExpressionElementVisitor);
+            var containsLexicalThis = !!(node.transformFlags & 16384 /* ContainsLexicalThis */);
+            switch (compilerOptions.module) {
+                case ts.ModuleKind.AMD:
+                    return createImportCallExpressionAMD(argument, containsLexicalThis);
+                case ts.ModuleKind.UMD:
+                    return createImportCallExpressionUMD(argument, containsLexicalThis);
+                case ts.ModuleKind.CommonJS:
+                default:
+                    return createImportCallExpressionCommonJS(argument, containsLexicalThis);
+            }
+        }
+        function createImportCallExpressionUMD(arg, containsLexicalThis) {
+            // (function (factory) {
+            //      ... (regular UMD)
+            // }
+            // })(function (require, exports, useSyncRequire) {
+            //      "use strict";
+            //      Object.defineProperty(exports, "__esModule", { value: true });
+            //      var __syncRequire = typeof module === "object" && typeof module.exports === "object";
+            //      var __resolved = new Promise(function (resolve) { resolve(); });
+            //      .....
+            //      __syncRequire
+            //          ? __resolved.then(function () { return require(x); }) /*CommonJs Require*/
+            //          : new Promise(function (_a, _b) { require([x], _a, _b); }); /*Amd Require*/
+            // });
+            needUMDDynamicImportHelper = true;
+            if (ts.isSimpleCopiableExpression(arg)) {
+                var argClone = ts.isGeneratedIdentifier(arg) ? arg : ts.isStringLiteral(arg) ? ts.createLiteral(arg) : ts.setEmitFlags(ts.setTextRange(ts.getSynthesizedClone(arg), arg), 1536 /* NoComments */);
+                return ts.createConditional(
+                /*condition*/ ts.createIdentifier("__syncRequire"), 
+                /*whenTrue*/ createImportCallExpressionCommonJS(arg, containsLexicalThis), 
+                /*whenFalse*/ createImportCallExpressionAMD(argClone, containsLexicalThis));
+            }
+            else {
+                var temp = ts.createTempVariable(hoistVariableDeclaration);
+                return ts.createComma(ts.createAssignment(temp, arg), ts.createConditional(
+                /*condition*/ ts.createIdentifier("__syncRequire"), 
+                /*whenTrue*/ createImportCallExpressionCommonJS(temp, containsLexicalThis), 
+                /*whenFalse*/ createImportCallExpressionAMD(temp, containsLexicalThis)));
+            }
+        }
+        function createImportCallExpressionAMD(arg, containsLexicalThis) {
+            // improt("./blah")
+            // emit as
+            // define(["require", "exports", "blah"], function (require, exports) {
+            //     ...
+            //     new Promise(function (_a, _b) { require([x], _a, _b); }); /*Amd Require*/
+            // });
+            var resolve = ts.createUniqueName("resolve");
+            var reject = ts.createUniqueName("reject");
+            var parameters = [
+                ts.createParameter(/*decorator*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, /*name*/ resolve),
+                ts.createParameter(/*decorator*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, /*name*/ reject)
+            ];
+            var body = ts.createBlock([
+                ts.createStatement(ts.createCall(ts.createIdentifier("require"), 
+                /*typeArguments*/ undefined, [ts.createArrayLiteral([arg || ts.createOmittedExpression()]), resolve, reject]))
+            ]);
+            var func;
+            if (languageVersion >= 2 /* ES2015 */) {
+                func = ts.createArrowFunction(
+                /*modifiers*/ undefined, 
+                /*typeParameters*/ undefined, parameters, 
+                /*type*/ undefined, 
+                /*equalsGreaterThanToken*/ undefined, body);
+            }
+            else {
+                func = ts.createFunctionExpression(
+                /*modifiers*/ undefined, 
+                /*asteriskToken*/ undefined, 
+                /*name*/ undefined, 
+                /*typeParameters*/ undefined, parameters, 
+                /*type*/ undefined, body);
+                // if there is a lexical 'this' in the import call arguments, ensure we indicate
+                // that this new function expression indicates it captures 'this' so that the
+                // es2015 transformer will properly substitute 'this' with '_this'.
+                if (containsLexicalThis) {
+                    ts.setEmitFlags(func, 8 /* CapturesThis */);
+                }
+            }
+            var promise = ts.createNew(ts.createIdentifier("Promise"), /*typeArguments*/ undefined, [func]);
+            if (compilerOptions.esModuleInterop) {
+                context.requestEmitHelper(importStarHelper);
+                return ts.createCall(ts.createPropertyAccess(promise, ts.createIdentifier("then")), /*typeArguments*/ undefined, [ts.getHelperName("__importStar")]);
+            }
+            return promise;
+        }
+        function createImportCallExpressionCommonJS(arg, containsLexicalThis) {
+            // import("./blah")
+            // emit as
+            // Promise.resolve().then(function () { return require(x); }) /*CommonJs Require*/
+            // We have to wrap require in then callback so that require is done in asynchronously
+            // if we simply do require in resolve callback in Promise constructor. We will execute the loading immediately
+            var promiseResolveCall = ts.createCall(ts.createPropertyAccess(ts.createIdentifier("Promise"), "resolve"), /*typeArguments*/ undefined, /*argumentsArray*/ []);
+            var requireCall = ts.createCall(ts.createIdentifier("require"), /*typeArguments*/ undefined, arg ? [arg] : []);
+            if (compilerOptions.esModuleInterop) {
+                context.requestEmitHelper(importStarHelper);
+                requireCall = ts.createCall(ts.getHelperName("__importStar"), /*typeArguments*/ undefined, [requireCall]);
+            }
+            var func;
+            if (languageVersion >= 2 /* ES2015 */) {
+                func = ts.createArrowFunction(
+                /*modifiers*/ undefined, 
+                /*typeParameters*/ undefined, 
+                /*parameters*/ [], 
+                /*type*/ undefined, 
+                /*equalsGreaterThanToken*/ undefined, requireCall);
+            }
+            else {
+                func = ts.createFunctionExpression(
+                /*modifiers*/ undefined, 
+                /*asteriskToken*/ undefined, 
+                /*name*/ undefined, 
+                /*typeParameters*/ undefined, 
+                /*parameters*/ [], 
+                /*type*/ undefined, ts.createBlock([ts.createReturn(requireCall)]));
+                // if there is a lexical 'this' in the import call arguments, ensure we indicate
+                // that this new function expression indicates it captures 'this' so that the
+                // es2015 transformer will properly substitute 'this' with '_this'.
+                if (containsLexicalThis) {
+                    ts.setEmitFlags(func, 8 /* CapturesThis */);
+                }
+            }
+            return ts.createCall(ts.createPropertyAccess(promiseResolveCall, "then"), /*typeArguments*/ undefined, [func]);
+        }
+        function getHelperExpressionForImport(node, innerExpr) {
+            if (!compilerOptions.esModuleInterop || ts.getEmitFlags(node) & 67108864 /* NeverApplyImportHelper */) {
+                return innerExpr;
+            }
+            if (ts.getImportNeedsImportStarHelper(node)) {
+                context.requestEmitHelper(importStarHelper);
+                return ts.createCall(ts.getHelperName("__importStar"), /*typeArguments*/ undefined, [innerExpr]);
+            }
+            if (ts.getImportNeedsImportDefaultHelper(node)) {
+                context.requestEmitHelper(importDefaultHelper);
+                return ts.createCall(ts.getHelperName("__importDefault"), /*typeArguments*/ undefined, [innerExpr]);
+            }
+            return innerExpr;
+        }
+        /**
+         * Visits an ImportDeclaration node.
+         *
+         * @param node The node to visit.
+         */
+        function visitImportDeclaration(node) {
+            var statements;
+            var namespaceDeclaration = ts.getNamespaceDeclarationNode(node);
+            if (moduleKind !== ts.ModuleKind.AMD) {
+                if (!node.importClause) {
+                    // import "mod";
+                    return ts.setTextRange(ts.createStatement(createRequireCall(node)), node);
+                }
+                else {
+                    var variables = [];
+                    if (namespaceDeclaration && !ts.isDefaultImport(node)) {
+                        // import * as n from "mod";
+                        variables.push(ts.createVariableDeclaration(ts.getSynthesizedClone(namespaceDeclaration.name), 
+                        /*type*/ undefined, getHelperExpressionForImport(node, createRequireCall(node))));
+                    }
+                    else {
+                        // import d from "mod";
+                        // import { x, y } from "mod";
+                        // import d, { x, y } from "mod";
+                        // import d, * as n from "mod";
+                        variables.push(ts.createVariableDeclaration(ts.getGeneratedNameForNode(node), 
+                        /*type*/ undefined, getHelperExpressionForImport(node, createRequireCall(node))));
+                        if (namespaceDeclaration && ts.isDefaultImport(node)) {
+                            variables.push(ts.createVariableDeclaration(ts.getSynthesizedClone(namespaceDeclaration.name), 
+                            /*type*/ undefined, ts.getGeneratedNameForNode(node)));
+                        }
+                    }
+                    statements = ts.append(statements, ts.setTextRange(ts.createVariableStatement(
+                    /*modifiers*/ undefined, ts.createVariableDeclarationList(variables, languageVersion >= 2 /* ES2015 */ ? 2 /* Const */ : 0 /* None */)), 
+                    /*location*/ node));
+                }
+            }
+            else if (namespaceDeclaration && ts.isDefaultImport(node)) {
+                // import d, * as n from "mod";
+                statements = ts.append(statements, ts.createVariableStatement(
+                /*modifiers*/ undefined, ts.createVariableDeclarationList([
+                    ts.setTextRange(ts.createVariableDeclaration(ts.getSynthesizedClone(namespaceDeclaration.name), 
+                    /*type*/ undefined, ts.getGeneratedNameForNode(node)), 
+                    /*location*/ node)
+                ], languageVersion >= 2 /* ES2015 */ ? 2 /* Const */ : 0 /* None */)));
+            }
+            if (hasAssociatedEndOfDeclarationMarker(node)) {
+                // Defer exports until we encounter an EndOfDeclarationMarker node
+                var id = ts.getOriginalNodeId(node);
+                deferredExports[id] = appendExportsOfImportDeclaration(deferredExports[id], node);
+            }
+            else {
+                statements = appendExportsOfImportDeclaration(statements, node);
+            }
+            return ts.singleOrMany(statements);
+        }
+        /**
+         * Creates a `require()` call to import an external module.
+         *
+         * @param importNode The declararation to import.
+         */
+        function createRequireCall(importNode) {
+            var moduleName = ts.getExternalModuleNameLiteral(importNode, currentSourceFile, host, resolver, compilerOptions);
+            var args = [];
+            if (moduleName) {
+                args.push(moduleName);
+            }
+            return ts.createCall(ts.createIdentifier("require"), /*typeArguments*/ undefined, args);
+        }
+        /**
+         * Visits an ImportEqualsDeclaration node.
+         *
+         * @param node The node to visit.
+         */
+        function visitImportEqualsDeclaration(node) {
+            ts.Debug.assert(ts.isExternalModuleImportEqualsDeclaration(node), "import= for internal module references should be handled in an earlier transformer.");
+            var statements;
+            if (moduleKind !== ts.ModuleKind.AMD) {
+                if (ts.hasModifier(node, 1 /* Export */)) {
+                    statements = ts.append(statements, ts.setTextRange(ts.createStatement(createExportExpression(node.name, createRequireCall(node))), node));
+                }
+                else {
+                    statements = ts.append(statements, ts.setTextRange(ts.createVariableStatement(
+                    /*modifiers*/ undefined, ts.createVariableDeclarationList([
+                        ts.createVariableDeclaration(ts.getSynthesizedClone(node.name), 
+                        /*type*/ undefined, createRequireCall(node))
+                    ], 
+                    /*flags*/ languageVersion >= 2 /* ES2015 */ ? 2 /* Const */ : 0 /* None */)), node));
+                }
+            }
+            else {
+                if (ts.hasModifier(node, 1 /* Export */)) {
+                    statements = ts.append(statements, ts.setTextRange(ts.createStatement(createExportExpression(ts.getExportName(node), ts.getLocalName(node))), node));
+                }
+            }
+            if (hasAssociatedEndOfDeclarationMarker(node)) {
+                // Defer exports until we encounter an EndOfDeclarationMarker node
+                var id = ts.getOriginalNodeId(node);
+                deferredExports[id] = appendExportsOfImportEqualsDeclaration(deferredExports[id], node);
+            }
+            else {
+                statements = appendExportsOfImportEqualsDeclaration(statements, node);
+            }
+            return ts.singleOrMany(statements);
+        }
+        /**
+         * Visits an ExportDeclaration node.
+         *
+         * @param The node to visit.
+         */
+        function visitExportDeclaration(node) {
+            if (!node.moduleSpecifier) {
+                // Elide export declarations with no module specifier as they are handled
+                // elsewhere.
+                return undefined;
+            }
+            var generatedName = ts.getGeneratedNameForNode(node);
+            if (node.exportClause) {
+                var statements = [];
+                // export { x, y } from "mod";
+                if (moduleKind !== ts.ModuleKind.AMD) {
+                    statements.push(ts.setTextRange(ts.createVariableStatement(
+                    /*modifiers*/ undefined, ts.createVariableDeclarationList([
+                        ts.createVariableDeclaration(generatedName, 
+                        /*type*/ undefined, createRequireCall(node))
+                    ])), 
+                    /*location*/ node));
+                }
+                for (var _i = 0, _a = node.exportClause.elements; _i < _a.length; _i++) {
+                    var specifier = _a[_i];
+                    var exportedValue = ts.createPropertyAccess(generatedName, specifier.propertyName || specifier.name);
+                    statements.push(ts.setTextRange(ts.createStatement(createExportExpression(ts.getExportName(specifier), exportedValue)), specifier));
+                }
+                return ts.singleOrMany(statements);
+            }
+            else {
+                // export * from "mod";
+                return ts.setTextRange(ts.createStatement(createExportStarHelper(context, moduleKind !== ts.ModuleKind.AMD ? createRequireCall(node) : generatedName)), node);
+            }
+        }
+        /**
+         * Visits an ExportAssignment node.
+         *
+         * @param node The node to visit.
+         */
+        function visitExportAssignment(node) {
+            if (node.isExportEquals) {
+                return undefined;
+            }
+            var statements;
+            var original = node.original;
+            if (original && hasAssociatedEndOfDeclarationMarker(original)) {
+                // Defer exports until we encounter an EndOfDeclarationMarker node
+                var id = ts.getOriginalNodeId(node);
+                deferredExports[id] = appendExportStatement(deferredExports[id], ts.createIdentifier("default"), ts.visitNode(node.expression, moduleExpressionElementVisitor), /*location*/ node, /*allowComments*/ true);
+            }
+            else {
+                statements = appendExportStatement(statements, ts.createIdentifier("default"), ts.visitNode(node.expression, moduleExpressionElementVisitor), /*location*/ node, /*allowComments*/ true);
+            }
+            return ts.singleOrMany(statements);
+        }
+        /**
+         * Visits a FunctionDeclaration node.
+         *
+         * @param node The node to visit.
+         */
+        function visitFunctionDeclaration(node) {
+            var statements;
+            if (ts.hasModifier(node, 1 /* Export */)) {
+                statements = ts.append(statements, ts.setOriginalNode(ts.setTextRange(ts.createFunctionDeclaration(
+                /*decorators*/ undefined, ts.visitNodes(node.modifiers, modifierVisitor, ts.isModifier), node.asteriskToken, ts.getDeclarationName(node, /*allowComments*/ true, /*allowSourceMaps*/ true), 
+                /*typeParameters*/ undefined, ts.visitNodes(node.parameters, moduleExpressionElementVisitor), 
+                /*type*/ undefined, ts.visitEachChild(node.body, moduleExpressionElementVisitor, context)), 
+                /*location*/ node), 
+                /*original*/ node));
+            }
+            else {
+                statements = ts.append(statements, ts.visitEachChild(node, moduleExpressionElementVisitor, context));
+            }
+            if (hasAssociatedEndOfDeclarationMarker(node)) {
+                // Defer exports until we encounter an EndOfDeclarationMarker node
+                var id = ts.getOriginalNodeId(node);
+                deferredExports[id] = appendExportsOfHoistedDeclaration(deferredExports[id], node);
+            }
+            else {
+                statements = appendExportsOfHoistedDeclaration(statements, node);
+            }
+            return ts.singleOrMany(statements);
+        }
+        /**
+         * Visits a ClassDeclaration node.
+         *
+         * @param node The node to visit.
+         */
+        function visitClassDeclaration(node) {
+            var statements;
+            if (ts.hasModifier(node, 1 /* Export */)) {
+                statements = ts.append(statements, ts.setOriginalNode(ts.setTextRange(ts.createClassDeclaration(
+                /*decorators*/ undefined, ts.visitNodes(node.modifiers, modifierVisitor, ts.isModifier), ts.getDeclarationName(node, /*allowComments*/ true, /*allowSourceMaps*/ true), 
+                /*typeParameters*/ undefined, ts.visitNodes(node.heritageClauses, moduleExpressionElementVisitor), ts.visitNodes(node.members, moduleExpressionElementVisitor)), node), node));
+            }
+            else {
+                statements = ts.append(statements, ts.visitEachChild(node, moduleExpressionElementVisitor, context));
+            }
+            if (hasAssociatedEndOfDeclarationMarker(node)) {
+                // Defer exports until we encounter an EndOfDeclarationMarker node
+                var id = ts.getOriginalNodeId(node);
+                deferredExports[id] = appendExportsOfHoistedDeclaration(deferredExports[id], node);
+            }
+            else {
+                statements = appendExportsOfHoistedDeclaration(statements, node);
+            }
+            return ts.singleOrMany(statements);
+        }
+        /**
+         * Visits a VariableStatement node.
+         *
+         * @param node The node to visit.
+         */
+        function visitVariableStatement(node) {
+            var statements;
+            var variables;
+            var expressions;
+            if (ts.hasModifier(node, 1 /* Export */)) {
+                var modifiers = void 0;
+                // If we're exporting these variables, then these just become assignments to 'exports.x'.
+                // We only want to emit assignments for variables with initializers.
+                for (var _i = 0, _a = node.declarationList.declarations; _i < _a.length; _i++) {
+                    var variable = _a[_i];
+                    if (ts.isIdentifier(variable.name) && ts.isLocalName(variable.name)) {
+                        if (!modifiers) {
+                            modifiers = ts.visitNodes(node.modifiers, modifierVisitor, ts.isModifier);
+                        }
+                        variables = ts.append(variables, variable);
+                    }
+                    else if (variable.initializer) {
+                        expressions = ts.append(expressions, transformInitializedVariable(variable));
+                    }
+                }
+                if (variables) {
+                    statements = ts.append(statements, ts.updateVariableStatement(node, modifiers, ts.updateVariableDeclarationList(node.declarationList, variables)));
+                }
+                if (expressions) {
+                    statements = ts.append(statements, ts.setTextRange(ts.createStatement(ts.inlineExpressions(expressions)), node));
+                }
+            }
+            else {
+                statements = ts.append(statements, ts.visitEachChild(node, moduleExpressionElementVisitor, context));
+            }
+            if (hasAssociatedEndOfDeclarationMarker(node)) {
+                // Defer exports until we encounter an EndOfDeclarationMarker node
+                var id = ts.getOriginalNodeId(node);
+                deferredExports[id] = appendExportsOfVariableStatement(deferredExports[id], node);
+            }
+            else {
+                statements = appendExportsOfVariableStatement(statements, node);
+            }
+            return ts.singleOrMany(statements);
+        }
+        function createAllExportExpressions(name, value, location) {
+            var exportedNames = getExports(name);
+            if (exportedNames) {
+                // For each additional export of the declaration, apply an export assignment.
+                var expression = ts.isExportName(name) ? value : ts.createAssignment(name, value);
+                for (var _i = 0, exportedNames_1 = exportedNames; _i < exportedNames_1.length; _i++) {
+                    var exportName = exportedNames_1[_i];
+                    // Mark the node to prevent triggering substitution.
+                    ts.setEmitFlags(expression, 4 /* NoSubstitution */);
+                    expression = createExportExpression(exportName, expression, /*location*/ location);
+                }
+                return expression;
+            }
+            return ts.createAssignment(name, value);
+        }
+        /**
+         * Transforms an exported variable with an initializer into an expression.
+         *
+         * @param node The node to transform.
+         */
+        function transformInitializedVariable(node) {
+            if (ts.isBindingPattern(node.name)) {
+                return ts.flattenDestructuringAssignment(ts.visitNode(node, moduleExpressionElementVisitor), 
+                /*visitor*/ undefined, context, 0 /* All */, 
+                /*needsValue*/ false, createAllExportExpressions);
+            }
+            else {
+                return ts.createAssignment(ts.setTextRange(ts.createPropertyAccess(ts.createIdentifier("exports"), node.name), 
+                /*location*/ node.name), ts.visitNode(node.initializer, moduleExpressionElementVisitor));
+            }
+        }
+        /**
+         * Visits a MergeDeclarationMarker used as a placeholder for the beginning of a merged
+         * and transformed declaration.
+         *
+         * @param node The node to visit.
+         */
+        function visitMergeDeclarationMarker(node) {
+            // For an EnumDeclaration or ModuleDeclaration that merges with a preceeding
+            // declaration we do not emit a leading variable declaration. To preserve the
+            // begin/end semantics of the declararation and to properly handle exports
+            // we wrapped the leading variable declaration in a `MergeDeclarationMarker`.
+            //
+            // To balance the declaration, add the exports of the elided variable
+            // statement.
+            if (hasAssociatedEndOfDeclarationMarker(node) && node.original.kind === 214 /* VariableStatement */) {
+                var id = ts.getOriginalNodeId(node);
+                deferredExports[id] = appendExportsOfVariableStatement(deferredExports[id], node.original);
+            }
+            return node;
+        }
+        /**
+         * Determines whether a node has an associated EndOfDeclarationMarker.
+         *
+         * @param node The node to test.
+         */
+        function hasAssociatedEndOfDeclarationMarker(node) {
+            return (ts.getEmitFlags(node) & 4194304 /* HasEndOfDeclarationMarker */) !== 0;
+        }
+        /**
+         * Visits a DeclarationMarker used as a placeholder for the end of a transformed
+         * declaration.
+         *
+         * @param node The node to visit.
+         */
+        function visitEndOfDeclarationMarker(node) {
+            // For some transformations we emit an `EndOfDeclarationMarker` to mark the actual
+            // end of the transformed declaration. We use this marker to emit any deferred exports
+            // of the declaration.
+            var id = ts.getOriginalNodeId(node);
+            var statements = deferredExports[id];
+            if (statements) {
+                delete deferredExports[id];
+                return ts.append(statements, node);
+            }
+            return node;
+        }
+        /**
+         * Appends the exports of an ImportDeclaration to a statement list, returning the
+         * statement list.
+         *
+         * @param statements A statement list to which the down-level export statements are to be
+         * appended. If `statements` is `undefined`, a new array is allocated if statements are
+         * appended.
+         * @param decl The declaration whose exports are to be recorded.
+         */
+        function appendExportsOfImportDeclaration(statements, decl) {
+            if (currentModuleInfo.exportEquals) {
+                return statements;
+            }
+            var importClause = decl.importClause;
+            if (!importClause) {
+                return statements;
+            }
+            if (importClause.name) {
+                statements = appendExportsOfDeclaration(statements, importClause);
+            }
+            var namedBindings = importClause.namedBindings;
+            if (namedBindings) {
+                switch (namedBindings.kind) {
+                    case 246 /* NamespaceImport */:
+                        statements = appendExportsOfDeclaration(statements, namedBindings);
+                        break;
+                    case 247 /* NamedImports */:
+                        for (var _i = 0, _a = namedBindings.elements; _i < _a.length; _i++) {
+                            var importBinding = _a[_i];
+                            statements = appendExportsOfDeclaration(statements, importBinding);
+                        }
+                        break;
+                }
+            }
+            return statements;
+        }
+        /**
+         * Appends the exports of an ImportEqualsDeclaration to a statement list, returning the
+         * statement list.
+         *
+         * @param statements A statement list to which the down-level export statements are to be
+         * appended. If `statements` is `undefined`, a new array is allocated if statements are
+         * appended.
+         * @param decl The declaration whose exports are to be recorded.
+         */
+        function appendExportsOfImportEqualsDeclaration(statements, decl) {
+            if (currentModuleInfo.exportEquals) {
+                return statements;
+            }
+            return appendExportsOfDeclaration(statements, decl);
+        }
+        /**
+         * Appends the exports of a VariableStatement to a statement list, returning the statement
+         * list.
+         *
+         * @param statements A statement list to which the down-level export statements are to be
+         * appended. If `statements` is `undefined`, a new array is allocated if statements are
+         * appended.
+         * @param node The VariableStatement whose exports are to be recorded.
+         */
+        function appendExportsOfVariableStatement(statements, node) {
+            if (currentModuleInfo.exportEquals) {
+                return statements;
+            }
+            for (var _i = 0, _a = node.declarationList.declarations; _i < _a.length; _i++) {
+                var decl = _a[_i];
+                statements = appendExportsOfBindingElement(statements, decl);
+            }
+            return statements;
+        }
+        /**
+         * Appends the exports of a VariableDeclaration or BindingElement to a statement list,
+         * returning the statement list.
+         *
+         * @param statements A statement list to which the down-level export statements are to be
+         * appended. If `statements` is `undefined`, a new array is allocated if statements are
+         * appended.
+         * @param decl The declaration whose exports are to be recorded.
+         */
+        function appendExportsOfBindingElement(statements, decl) {
+            if (currentModuleInfo.exportEquals) {
+                return statements;
+            }
+            if (ts.isBindingPattern(decl.name)) {
+                for (var _i = 0, _a = decl.name.elements; _i < _a.length; _i++) {
+                    var element = _a[_i];
+                    if (!ts.isOmittedExpression(element)) {
+                        statements = appendExportsOfBindingElement(statements, element);
+                    }
+                }
+            }
+            else if (!ts.isGeneratedIdentifier(decl.name)) {
+                statements = appendExportsOfDeclaration(statements, decl);
+            }
+            return statements;
+        }
+        /**
+         * Appends the exports of a ClassDeclaration or FunctionDeclaration to a statement list,
+         * returning the statement list.
+         *
+         * @param statements A statement list to which the down-level export statements are to be
+         * appended. If `statements` is `undefined`, a new array is allocated if statements are
+         * appended.
+         * @param decl The declaration whose exports are to be recorded.
+         */
+        function appendExportsOfHoistedDeclaration(statements, decl) {
+            if (currentModuleInfo.exportEquals) {
+                return statements;
+            }
+            if (ts.hasModifier(decl, 1 /* Export */)) {
+                var exportName = ts.hasModifier(decl, 512 /* Default */) ? ts.createIdentifier("default") : ts.getDeclarationName(decl);
+                statements = appendExportStatement(statements, exportName, ts.getLocalName(decl), /*location*/ decl);
+            }
+            if (decl.name) {
+                statements = appendExportsOfDeclaration(statements, decl);
+            }
+            return statements;
+        }
+        /**
+         * Appends the exports of a declaration to a statement list, returning the statement list.
+         *
+         * @param statements A statement list to which the down-level export statements are to be
+         * appended. If `statements` is `undefined`, a new array is allocated if statements are
+         * appended.
+         * @param decl The declaration to export.
+         */
+        function appendExportsOfDeclaration(statements, decl) {
+            var name = ts.getDeclarationName(decl);
+            var exportSpecifiers = currentModuleInfo.exportSpecifiers.get(ts.idText(name));
+            if (exportSpecifiers) {
+                for (var _i = 0, exportSpecifiers_1 = exportSpecifiers; _i < exportSpecifiers_1.length; _i++) {
+                    var exportSpecifier = exportSpecifiers_1[_i];
+                    statements = appendExportStatement(statements, exportSpecifier.name, name, /*location*/ exportSpecifier.name);
+                }
+            }
+            return statements;
+        }
+        /**
+         * Appends the down-level representation of an export to a statement list, returning the
+         * statement list.
+         *
+         * @param statements A statement list to which the down-level export statements are to be
+         * appended. If `statements` is `undefined`, a new array is allocated if statements are
+         * appended.
+         * @param exportName The name of the export.
+         * @param expression The expression to export.
+         * @param location The location to use for source maps and comments for the export.
+         * @param allowComments Whether to allow comments on the export.
+         */
+        function appendExportStatement(statements, exportName, expression, location, allowComments) {
+            statements = ts.append(statements, createExportStatement(exportName, expression, location, allowComments));
+            return statements;
+        }
+        function createUnderscoreUnderscoreESModule() {
+            var statement;
+            if (languageVersion === 0 /* ES3 */) {
+                statement = ts.createStatement(createExportExpression(ts.createIdentifier("__esModule"), ts.createLiteral(/*value*/ true)));
+            }
+            else {
+                statement = ts.createStatement(ts.createCall(ts.createPropertyAccess(ts.createIdentifier("Object"), "defineProperty"), 
+                /*typeArguments*/ undefined, [
+                    ts.createIdentifier("exports"),
+                    ts.createLiteral("__esModule"),
+                    ts.createObjectLiteral([
+                        ts.createPropertyAssignment("value", ts.createLiteral(/*value*/ true))
+                    ])
+                ]));
+            }
+            ts.setEmitFlags(statement, 1048576 /* CustomPrologue */);
+            return statement;
+        }
+        /**
+         * Creates a call to the current file's export function to export a value.
+         *
+         * @param name The bound name of the export.
+         * @param value The exported value.
+         * @param location The location to use for source maps and comments for the export.
+         * @param allowComments An optional value indicating whether to emit comments for the statement.
+         */
+        function createExportStatement(name, value, location, allowComments) {
+            var statement = ts.setTextRange(ts.createStatement(createExportExpression(name, value)), location);
+            ts.startOnNewLine(statement);
+            if (!allowComments) {
+                ts.setEmitFlags(statement, 1536 /* NoComments */);
+            }
+            return statement;
+        }
+        /**
+         * Creates a call to the current file's export function to export a value.
+         *
+         * @param name The bound name of the export.
+         * @param value The exported value.
+         * @param location The location to use for source maps and comments for the export.
+         */
+        function createExportExpression(name, value, location) {
+            return ts.setTextRange(ts.createAssignment(ts.createPropertyAccess(ts.createIdentifier("exports"), ts.getSynthesizedClone(name)), value), location);
+        }
+        //
+        // Modifier Visitors
+        //
+        /**
+         * Visit nodes to elide module-specific modifiers.
+         *
+         * @param node The node to visit.
+         */
+        function modifierVisitor(node) {
+            // Elide module-specific modifiers.
+            switch (node.kind) {
+                case 84 /* ExportKeyword */:
+                case 79 /* DefaultKeyword */:
+                    return undefined;
+            }
+            return node;
+        }
+        //
+        // Emit Notification
+        //
+        /**
+         * Hook for node emit notifications.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to emit.
+         * @param emit A callback used to emit the node in the printer.
+         */
+        function onEmitNode(hint, node, emitCallback) {
+            if (node.kind === 274 /* SourceFile */) {
+                currentSourceFile = node;
+                currentModuleInfo = moduleInfoMap[ts.getOriginalNodeId(currentSourceFile)];
+                noSubstitution = [];
+                previousOnEmitNode(hint, node, emitCallback);
+                currentSourceFile = undefined;
+                currentModuleInfo = undefined;
+                noSubstitution = undefined;
+            }
+            else {
+                previousOnEmitNode(hint, node, emitCallback);
+            }
+        }
+        //
+        // Substitutions
+        //
+        /**
+         * Hooks node substitutions.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to substitute.
+         */
+        function onSubstituteNode(hint, node) {
+            node = previousOnSubstituteNode(hint, node);
+            if (node.id && noSubstitution[node.id]) {
+                return node;
+            }
+            if (hint === 1 /* Expression */) {
+                return substituteExpression(node);
+            }
+            else if (ts.isShorthandPropertyAssignment(node)) {
+                return substituteShorthandPropertyAssignment(node);
+            }
+            return node;
+        }
+        /**
+         * Substitution for a ShorthandPropertyAssignment whose declaration name is an imported
+         * or exported symbol.
+         *
+         * @param node The node to substitute.
+         */
+        function substituteShorthandPropertyAssignment(node) {
+            var name = node.name;
+            var exportedOrImportedName = substituteExpressionIdentifier(name);
+            if (exportedOrImportedName !== name) {
+                // A shorthand property with an assignment initializer is probably part of a
+                // destructuring assignment
+                if (node.objectAssignmentInitializer) {
+                    var initializer = ts.createAssignment(exportedOrImportedName, node.objectAssignmentInitializer);
+                    return ts.setTextRange(ts.createPropertyAssignment(name, initializer), node);
+                }
+                return ts.setTextRange(ts.createPropertyAssignment(name, exportedOrImportedName), node);
+            }
+            return node;
+        }
+        /**
+         * Substitution for an Expression that may contain an imported or exported symbol.
+         *
+         * @param node The node to substitute.
+         */
+        function substituteExpression(node) {
+            switch (node.kind) {
+                case 71 /* Identifier */:
+                    return substituteExpressionIdentifier(node);
+                case 200 /* BinaryExpression */:
+                    return substituteBinaryExpression(node);
+                case 199 /* PostfixUnaryExpression */:
+                case 198 /* PrefixUnaryExpression */:
+                    return substituteUnaryExpression(node);
+            }
+            return node;
+        }
+        /**
+         * Substitution for an Identifier expression that may contain an imported or exported
+         * symbol.
+         *
+         * @param node The node to substitute.
+         */
+        function substituteExpressionIdentifier(node) {
+            if (ts.getEmitFlags(node) & 4096 /* HelperName */) {
+                var externalHelpersModuleName = ts.getExternalHelpersModuleName(currentSourceFile);
+                if (externalHelpersModuleName) {
+                    return ts.createPropertyAccess(externalHelpersModuleName, node);
+                }
+                return node;
+            }
+            if (!ts.isGeneratedIdentifier(node) && !ts.isLocalName(node)) {
+                var exportContainer = resolver.getReferencedExportContainer(node, ts.isExportName(node));
+                if (exportContainer && exportContainer.kind === 274 /* SourceFile */) {
+                    return ts.setTextRange(ts.createPropertyAccess(ts.createIdentifier("exports"), ts.getSynthesizedClone(node)), 
+                    /*location*/ node);
+                }
+                var importDeclaration = resolver.getReferencedImportDeclaration(node);
+                if (importDeclaration) {
+                    if (ts.isImportClause(importDeclaration)) {
+                        return ts.setTextRange(ts.createPropertyAccess(ts.getGeneratedNameForNode(importDeclaration.parent), ts.createIdentifier("default")), 
+                        /*location*/ node);
+                    }
+                    else if (ts.isImportSpecifier(importDeclaration)) {
+                        var name = importDeclaration.propertyName || importDeclaration.name;
+                        return ts.setTextRange(ts.createPropertyAccess(ts.getGeneratedNameForNode(importDeclaration.parent.parent.parent), ts.getSynthesizedClone(name)), 
+                        /*location*/ node);
+                    }
+                }
+            }
+            return node;
+        }
+        /**
+         * Substitution for a BinaryExpression that may contain an imported or exported symbol.
+         *
+         * @param node The node to substitute.
+         */
+        function substituteBinaryExpression(node) {
+            // When we see an assignment expression whose left-hand side is an exported symbol,
+            // we should ensure all exports of that symbol are updated with the correct value.
+            //
+            // - We do not substitute generated identifiers for any reason.
+            // - We do not substitute identifiers tagged with the LocalName flag.
+            // - We do not substitute identifiers that were originally the name of an enum or
+            //   namespace due to how they are transformed in TypeScript.
+            // - We only substitute identifiers that are exported at the top level.
+            if (ts.isAssignmentOperator(node.operatorToken.kind)
+                && ts.isIdentifier(node.left)
+                && !ts.isGeneratedIdentifier(node.left)
+                && !ts.isLocalName(node.left)
+                && !ts.isDeclarationNameOfEnumOrNamespace(node.left)) {
+                var exportedNames = getExports(node.left);
+                if (exportedNames) {
+                    // For each additional export of the declaration, apply an export assignment.
+                    var expression = node;
+                    for (var _i = 0, exportedNames_2 = exportedNames; _i < exportedNames_2.length; _i++) {
+                        var exportName = exportedNames_2[_i];
+                        // Mark the node to prevent triggering this rule again.
+                        noSubstitution[ts.getNodeId(expression)] = true;
+                        expression = createExportExpression(exportName, expression, /*location*/ node);
+                    }
+                    return expression;
+                }
+            }
+            return node;
+        }
+        /**
+         * Substitution for a UnaryExpression that may contain an imported or exported symbol.
+         *
+         * @param node The node to substitute.
+         */
+        function substituteUnaryExpression(node) {
+            // When we see a prefix or postfix increment expression whose operand is an exported
+            // symbol, we should ensure all exports of that symbol are updated with the correct
+            // value.
+            //
+            // - We do not substitute generated identifiers for any reason.
+            // - We do not substitute identifiers tagged with the LocalName flag.
+            // - We do not substitute identifiers that were originally the name of an enum or
+            //   namespace due to how they are transformed in TypeScript.
+            // - We only substitute identifiers that are exported at the top level.
+            if ((node.operator === 43 /* PlusPlusToken */ || node.operator === 44 /* MinusMinusToken */)
+                && ts.isIdentifier(node.operand)
+                && !ts.isGeneratedIdentifier(node.operand)
+                && !ts.isLocalName(node.operand)
+                && !ts.isDeclarationNameOfEnumOrNamespace(node.operand)) {
+                var exportedNames = getExports(node.operand);
+                if (exportedNames) {
+                    var expression = node.kind === 199 /* PostfixUnaryExpression */
+                        ? ts.setTextRange(ts.createBinary(node.operand, ts.createToken(node.operator === 43 /* PlusPlusToken */ ? 59 /* PlusEqualsToken */ : 60 /* MinusEqualsToken */), ts.createLiteral(1)), 
+                        /*location*/ node)
+                        : node;
+                    for (var _i = 0, exportedNames_3 = exportedNames; _i < exportedNames_3.length; _i++) {
+                        var exportName = exportedNames_3[_i];
+                        // Mark the node to prevent triggering this rule again.
+                        noSubstitution[ts.getNodeId(expression)] = true;
+                        expression = createExportExpression(exportName, expression);
+                    }
+                    return expression;
+                }
+            }
+            return node;
+        }
+        /**
+         * Gets the additional exports of a name.
+         *
+         * @param name The name.
+         */
+        function getExports(name) {
+            if (!ts.isGeneratedIdentifier(name)) {
+                var valueDeclaration = resolver.getReferencedImportDeclaration(name)
+                    || resolver.getReferencedValueDeclaration(name);
+                if (valueDeclaration) {
+                    return currentModuleInfo
+                        && currentModuleInfo.exportedBindings[ts.getOriginalNodeId(valueDeclaration)];
+                }
+            }
+        }
+    }
+    ts.transformModule = transformModule;
+    // emit output for the __export helper function
+    var exportStarHelper = {
+        name: "typescript:export-star",
+        scoped: true,
+        text: "\n            function __export(m) {\n                for (var p in m) if (!exports.hasOwnProperty(p)) exports[p] = m[p];\n            }"
+    };
+    function createExportStarHelper(context, module) {
+        var compilerOptions = context.getCompilerOptions();
+        return compilerOptions.importHelpers
+            ? ts.createCall(ts.getHelperName("__exportStar"), /*typeArguments*/ undefined, [module, ts.createIdentifier("exports")])
+            : ts.createCall(ts.createIdentifier("__export"), /*typeArguments*/ undefined, [module]);
+    }
+    // emit helper for dynamic import
+    var dynamicImportUMDHelper = {
+        name: "typescript:dynamicimport-sync-require",
+        scoped: true,
+        text: "\n            var __syncRequire = typeof module === \"object\" && typeof module.exports === \"object\";"
+    };
+    // emit helper for `import * as Name from "foo"`
+    var importStarHelper = {
+        name: "typescript:commonjsimportstar",
+        scoped: false,
+        text: "\nvar __importStar = (this && this.__importStar) || function (mod) {\n    if (mod && mod.__esModule) return mod;\n    var result = {};\n    if (mod != null) for (var k in mod) if (Object.hasOwnProperty.call(mod, k)) result[k] = mod[k];\n    result[\"default\"] = mod;\n    return result;\n};"
+    };
+    // emit helper for `import Name from "foo"`
+    var importDefaultHelper = {
+        name: "typescript:commonjsimportdefault",
+        scoped: false,
+        text: "\nvar __importDefault = (this && this.__importDefault) || function (mod) {\n    return (mod && mod.__esModule) ? mod : { \"default\": mod };\n};"
+    };
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    function transformSystemModule(context) {
+        var startLexicalEnvironment = context.startLexicalEnvironment, endLexicalEnvironment = context.endLexicalEnvironment, hoistVariableDeclaration = context.hoistVariableDeclaration;
+        var compilerOptions = context.getCompilerOptions();
+        var resolver = context.getEmitResolver();
+        var host = context.getEmitHost();
+        var previousOnSubstituteNode = context.onSubstituteNode;
+        var previousOnEmitNode = context.onEmitNode;
+        context.onSubstituteNode = onSubstituteNode;
+        context.onEmitNode = onEmitNode;
+        context.enableSubstitution(71 /* Identifier */); // Substitutes expression identifiers for imported symbols.
+        context.enableSubstitution(271 /* ShorthandPropertyAssignment */); // Substitutes expression identifiers for imported symbols
+        context.enableSubstitution(200 /* BinaryExpression */); // Substitutes assignments to exported symbols.
+        context.enableSubstitution(198 /* PrefixUnaryExpression */); // Substitutes updates to exported symbols.
+        context.enableSubstitution(199 /* PostfixUnaryExpression */); // Substitutes updates to exported symbols.
+        context.enableEmitNotification(274 /* SourceFile */); // Restore state when substituting nodes in a file.
+        var moduleInfoMap = []; // The ExternalModuleInfo for each file.
+        var deferredExports = []; // Exports to defer until an EndOfDeclarationMarker is found.
+        var exportFunctionsMap = []; // The export function associated with a source file.
+        var noSubstitutionMap = []; // Set of nodes for which substitution rules should be ignored for each file.
+        var currentSourceFile; // The current file.
+        var moduleInfo; // ExternalModuleInfo for the current file.
+        var exportFunction; // The export function for the current file.
+        var contextObject; // The context object for the current file.
+        var hoistedStatements;
+        var enclosingBlockScopedContainer;
+        var noSubstitution; // Set of nodes for which substitution rules should be ignored.
+        return ts.chainBundle(transformSourceFile);
+        /**
+         * Transforms the module aspects of a SourceFile.
+         *
+         * @param node The SourceFile node.
+         */
+        function transformSourceFile(node) {
+            if (node.isDeclarationFile || !(ts.isEffectiveExternalModule(node, compilerOptions) || node.transformFlags & 67108864 /* ContainsDynamicImport */)) {
+                return node;
+            }
+            var id = ts.getOriginalNodeId(node);
+            currentSourceFile = node;
+            enclosingBlockScopedContainer = node;
+            // System modules have the following shape:
+            //
+            //     System.register(['dep-1', ... 'dep-n'], function(exports) {/* module body function */})
+            //
+            // The parameter 'exports' here is a callback '<T>(name: string, value: T) => T' that
+            // is used to publish exported values. 'exports' returns its 'value' argument so in
+            // most cases expressions that mutate exported values can be rewritten as:
+            //
+            //     expr -> exports('name', expr)
+            //
+            // The only exception in this rule is postfix unary operators,
+            // see comment to 'substitutePostfixUnaryExpression' for more details
+            // Collect information about the external module and dependency groups.
+            moduleInfo = moduleInfoMap[id] = ts.collectExternalModuleInfo(node, resolver, compilerOptions);
+            // Make sure that the name of the 'exports' function does not conflict with
+            // existing identifiers.
+            exportFunction = ts.createUniqueName("exports");
+            exportFunctionsMap[id] = exportFunction;
+            contextObject = ts.createUniqueName("context");
+            // Add the body of the module.
+            var dependencyGroups = collectDependencyGroups(moduleInfo.externalImports);
+            var moduleBodyBlock = createSystemModuleBody(node, dependencyGroups);
+            var moduleBodyFunction = ts.createFunctionExpression(
+            /*modifiers*/ undefined, 
+            /*asteriskToken*/ undefined, 
+            /*name*/ undefined, 
+            /*typeParameters*/ undefined, [
+                ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, exportFunction),
+                ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, contextObject)
+            ], 
+            /*type*/ undefined, moduleBodyBlock);
+            // Write the call to `System.register`
+            // Clear the emit-helpers flag for later passes since we'll have already used it in the module body
+            // So the helper will be emit at the correct position instead of at the top of the source-file
+            var moduleName = ts.tryGetModuleNameFromFile(node, host, compilerOptions);
+            var dependencies = ts.createArrayLiteral(ts.map(dependencyGroups, function (dependencyGroup) { return dependencyGroup.name; }));
+            var updated = ts.setEmitFlags(ts.updateSourceFileNode(node, ts.setTextRange(ts.createNodeArray([
+                ts.createStatement(ts.createCall(ts.createPropertyAccess(ts.createIdentifier("System"), "register"), 
+                /*typeArguments*/ undefined, moduleName
+                    ? [moduleName, dependencies, moduleBodyFunction]
+                    : [dependencies, moduleBodyFunction]))
+            ]), node.statements)), 1024 /* NoTrailingComments */);
+            if (!(compilerOptions.outFile || compilerOptions.out)) {
+                ts.moveEmitHelpers(updated, moduleBodyBlock, function (helper) { return !helper.scoped; });
+            }
+            if (noSubstitution) {
+                noSubstitutionMap[id] = noSubstitution;
+                noSubstitution = undefined;
+            }
+            currentSourceFile = undefined;
+            moduleInfo = undefined;
+            exportFunction = undefined;
+            contextObject = undefined;
+            hoistedStatements = undefined;
+            enclosingBlockScopedContainer = undefined;
+            return ts.aggregateTransformFlags(updated);
+        }
+        /**
+         * Collects the dependency groups for this files imports.
+         *
+         * @param externalImports The imports for the file.
+         */
+        function collectDependencyGroups(externalImports) {
+            var groupIndices = ts.createMap();
+            var dependencyGroups = [];
+            for (var _i = 0, externalImports_1 = externalImports; _i < externalImports_1.length; _i++) {
+                var externalImport = externalImports_1[_i];
+                var externalModuleName = ts.getExternalModuleNameLiteral(externalImport, currentSourceFile, host, resolver, compilerOptions);
+                if (externalModuleName) {
+                    var text = externalModuleName.text;
+                    var groupIndex = groupIndices.get(text);
+                    if (groupIndex !== undefined) {
+                        // deduplicate/group entries in dependency list by the dependency name
+                        dependencyGroups[groupIndex].externalImports.push(externalImport);
+                    }
+                    else {
+                        groupIndices.set(text, dependencyGroups.length);
+                        dependencyGroups.push({
+                            name: externalModuleName,
+                            externalImports: [externalImport]
+                        });
+                    }
+                }
+            }
+            return dependencyGroups;
+        }
+        /**
+         * Adds the statements for the module body function for the source file.
+         *
+         * @param node The source file for the module.
+         * @param dependencyGroups The grouped dependencies of the module.
+         */
+        function createSystemModuleBody(node, dependencyGroups) {
+            // Shape of the body in system modules:
+            //
+            //  function (exports) {
+            //      <list of local aliases for imports>
+            //      <hoisted variable declarations>
+            //      <hoisted function declarations>
+            //      return {
+            //          setters: [
+            //              <list of setter function for imports>
+            //          ],
+            //          execute: function() {
+            //              <module statements>
+            //          }
+            //      }
+            //      <temp declarations>
+            //  }
+            //
+            // i.e:
+            //
+            //   import {x} from 'file1'
+            //   var y = 1;
+            //   export function foo() { return y + x(); }
+            //   console.log(y);
+            //
+            // Will be transformed to:
+            //
+            //  function(exports) {
+            //      function foo() { return y + file_1.x(); }
+            //      exports("foo", foo);
+            //      var file_1, y;
+            //      return {
+            //          setters: [
+            //              function(v) { file_1 = v }
+            //          ],
+            //          execute(): function() {
+            //              y = 1;
+            //              console.log(y);
+            //          }
+            //      };
+            //  }
+            var statements = [];
+            // We start a new lexical environment in this function body, but *not* in the
+            // body of the execute function. This allows us to emit temporary declarations
+            // only in the outer module body and not in the inner one.
+            startLexicalEnvironment();
+            // Add any prologue directives.
+            var ensureUseStrict = ts.getStrictOptionValue(compilerOptions, "alwaysStrict") || (!compilerOptions.noImplicitUseStrict && ts.isExternalModule(currentSourceFile));
+            var statementOffset = ts.addPrologue(statements, node.statements, ensureUseStrict, sourceElementVisitor);
+            // var __moduleName = context_1 && context_1.id;
+            statements.push(ts.createVariableStatement(
+            /*modifiers*/ undefined, ts.createVariableDeclarationList([
+                ts.createVariableDeclaration("__moduleName", 
+                /*type*/ undefined, ts.createLogicalAnd(contextObject, ts.createPropertyAccess(contextObject, "id")))
+            ])));
+            // Visit the synthetic external helpers import declaration if present
+            ts.visitNode(moduleInfo.externalHelpersImportDeclaration, sourceElementVisitor, ts.isStatement);
+            // Visit the statements of the source file, emitting any transformations into
+            // the `executeStatements` array. We do this *before* we fill the `setters` array
+            // as we both emit transformations as well as aggregate some data used when creating
+            // setters. This allows us to reduce the number of times we need to loop through the
+            // statements of the source file.
+            var executeStatements = ts.visitNodes(node.statements, sourceElementVisitor, ts.isStatement, statementOffset);
+            // Emit early exports for function declarations.
+            ts.addRange(statements, hoistedStatements);
+            // We emit hoisted variables early to align roughly with our previous emit output.
+            // Two key differences in this approach are:
+            // - Temporary variables will appear at the top rather than at the bottom of the file
+            ts.prependStatements(statements, endLexicalEnvironment());
+            var exportStarFunction = addExportStarIfNeeded(statements); // TODO: GH#18217
+            var moduleObject = ts.createObjectLiteral([
+                ts.createPropertyAssignment("setters", createSettersArray(exportStarFunction, dependencyGroups)),
+                ts.createPropertyAssignment("execute", ts.createFunctionExpression(
+                /*modifiers*/ undefined, 
+                /*asteriskToken*/ undefined, 
+                /*name*/ undefined, 
+                /*typeParameters*/ undefined, 
+                /*parameters*/ [], 
+                /*type*/ undefined, ts.createBlock(executeStatements, /*multiLine*/ true)))
+            ]);
+            moduleObject.multiLine = true;
+            statements.push(ts.createReturn(moduleObject));
+            return ts.createBlock(statements, /*multiLine*/ true);
+        }
+        /**
+         * Adds an exportStar function to a statement list if it is needed for the file.
+         *
+         * @param statements A statement list.
+         */
+        function addExportStarIfNeeded(statements) {
+            if (!moduleInfo.hasExportStarsToExportValues) {
+                return;
+            }
+            // when resolving exports local exported entries/indirect exported entries in the module
+            // should always win over entries with similar names that were added via star exports
+            // to support this we store names of local/indirect exported entries in a set.
+            // this set is used to filter names brought by star expors.
+            // local names set should only be added if we have anything exported
+            if (!moduleInfo.exportedNames && moduleInfo.exportSpecifiers.size === 0) {
+                // no exported declarations (export var ...) or export specifiers (export {x})
+                // check if we have any non star export declarations.
+                var hasExportDeclarationWithExportClause = false;
+                for (var _i = 0, _a = moduleInfo.externalImports; _i < _a.length; _i++) {
+                    var externalImport = _a[_i];
+                    if (externalImport.kind === 250 /* ExportDeclaration */ && externalImport.exportClause) {
+                        hasExportDeclarationWithExportClause = true;
+                        break;
+                    }
+                }
+                if (!hasExportDeclarationWithExportClause) {
+                    // we still need to emit exportStar helper
+                    var exportStarFunction_1 = createExportStarFunction(/*localNames*/ undefined);
+                    statements.push(exportStarFunction_1);
+                    return exportStarFunction_1.name;
+                }
+            }
+            var exportedNames = [];
+            if (moduleInfo.exportedNames) {
+                for (var _b = 0, _c = moduleInfo.exportedNames; _b < _c.length; _b++) {
+                    var exportedLocalName = _c[_b];
+                    if (exportedLocalName.escapedText === "default") {
+                        continue;
+                    }
+                    // write name of exported declaration, i.e 'export var x...'
+                    exportedNames.push(ts.createPropertyAssignment(ts.createLiteral(exportedLocalName), ts.createTrue()));
+                }
+            }
+            for (var _d = 0, _e = moduleInfo.externalImports; _d < _e.length; _d++) {
+                var externalImport = _e[_d];
+                if (externalImport.kind !== 250 /* ExportDeclaration */) {
+                    continue;
+                }
+                if (!externalImport.exportClause) {
+                    // export * from ...
+                    continue;
+                }
+                for (var _f = 0, _g = externalImport.exportClause.elements; _f < _g.length; _f++) {
+                    var element = _g[_f];
+                    // write name of indirectly exported entry, i.e. 'export {x} from ...'
+                    exportedNames.push(ts.createPropertyAssignment(ts.createLiteral(ts.idText(element.name || element.propertyName)), ts.createTrue()));
+                }
+            }
+            var exportedNamesStorageRef = ts.createUniqueName("exportedNames");
+            statements.push(ts.createVariableStatement(
+            /*modifiers*/ undefined, ts.createVariableDeclarationList([
+                ts.createVariableDeclaration(exportedNamesStorageRef, 
+                /*type*/ undefined, ts.createObjectLiteral(exportedNames, /*multiline*/ true))
+            ])));
+            var exportStarFunction = createExportStarFunction(exportedNamesStorageRef);
+            statements.push(exportStarFunction);
+            return exportStarFunction.name;
+        }
+        /**
+         * Creates an exportStar function for the file, with an optional set of excluded local
+         * names.
+         *
+         * @param localNames An optional reference to an object containing a set of excluded local
+         * names.
+         */
+        function createExportStarFunction(localNames) {
+            var exportStarFunction = ts.createUniqueName("exportStar");
+            var m = ts.createIdentifier("m");
+            var n = ts.createIdentifier("n");
+            var exports = ts.createIdentifier("exports");
+            var condition = ts.createStrictInequality(n, ts.createLiteral("default"));
+            if (localNames) {
+                condition = ts.createLogicalAnd(condition, ts.createLogicalNot(ts.createCall(ts.createPropertyAccess(localNames, "hasOwnProperty"), 
+                /*typeArguments*/ undefined, [n])));
+            }
+            return ts.createFunctionDeclaration(
+            /*decorators*/ undefined, 
+            /*modifiers*/ undefined, 
+            /*asteriskToken*/ undefined, exportStarFunction, 
+            /*typeParameters*/ undefined, [ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, m)], 
+            /*type*/ undefined, ts.createBlock([
+                ts.createVariableStatement(
+                /*modifiers*/ undefined, ts.createVariableDeclarationList([
+                    ts.createVariableDeclaration(exports, 
+                    /*type*/ undefined, ts.createObjectLiteral([]))
+                ])),
+                ts.createForIn(ts.createVariableDeclarationList([
+                    ts.createVariableDeclaration(n, /*type*/ undefined)
+                ]), m, ts.createBlock([
+                    ts.setEmitFlags(ts.createIf(condition, ts.createStatement(ts.createAssignment(ts.createElementAccess(exports, n), ts.createElementAccess(m, n)))), 1 /* SingleLine */)
+                ])),
+                ts.createStatement(ts.createCall(exportFunction, 
+                /*typeArguments*/ undefined, [exports]))
+            ], /*multiline*/ true));
+        }
+        /**
+         * Creates an array setter callbacks for each dependency group.
+         *
+         * @param exportStarFunction A reference to an exportStarFunction for the file.
+         * @param dependencyGroups An array of grouped dependencies.
+         */
+        function createSettersArray(exportStarFunction, dependencyGroups) {
+            var setters = [];
+            for (var _i = 0, dependencyGroups_1 = dependencyGroups; _i < dependencyGroups_1.length; _i++) {
+                var group_1 = dependencyGroups_1[_i];
+                // derive a unique name for parameter from the first named entry in the group
+                var localName = ts.forEach(group_1.externalImports, function (i) { return ts.getLocalNameForExternalImport(i, currentSourceFile); });
+                var parameterName = localName ? ts.getGeneratedNameForNode(localName) : ts.createUniqueName("");
+                var statements = [];
+                for (var _a = 0, _b = group_1.externalImports; _a < _b.length; _a++) {
+                    var entry = _b[_a];
+                    var importVariableName = ts.getLocalNameForExternalImport(entry, currentSourceFile); // TODO: GH#18217
+                    switch (entry.kind) {
+                        case 244 /* ImportDeclaration */:
+                            if (!entry.importClause) {
+                                // 'import "..."' case
+                                // module is imported only for side-effects, no emit required
+                                break;
+                            }
+                        // falls through
+                        case 243 /* ImportEqualsDeclaration */:
+                            ts.Debug.assert(importVariableName !== undefined);
+                            // save import into the local
+                            statements.push(ts.createStatement(ts.createAssignment(importVariableName, parameterName)));
+                            break;
+                        case 250 /* ExportDeclaration */:
+                            ts.Debug.assert(importVariableName !== undefined);
+                            if (entry.exportClause) {
+                                //  export {a, b as c} from 'foo'
+                                //
+                                // emit as:
+                                //
+                                //  exports_({
+                                //     "a": _["a"],
+                                //     "c": _["b"]
+                                //  });
+                                var properties = [];
+                                for (var _c = 0, _d = entry.exportClause.elements; _c < _d.length; _c++) {
+                                    var e = _d[_c];
+                                    properties.push(ts.createPropertyAssignment(ts.createLiteral(ts.idText(e.name)), ts.createElementAccess(parameterName, ts.createLiteral(ts.idText(e.propertyName || e.name)))));
+                                }
+                                statements.push(ts.createStatement(ts.createCall(exportFunction, 
+                                /*typeArguments*/ undefined, [ts.createObjectLiteral(properties, /*multiline*/ true)])));
+                            }
+                            else {
+                                //  export * from 'foo'
+                                //
+                                // emit as:
+                                //
+                                //  exportStar(foo_1_1);
+                                statements.push(ts.createStatement(ts.createCall(exportStarFunction, 
+                                /*typeArguments*/ undefined, [parameterName])));
+                            }
+                            break;
+                    }
+                }
+                setters.push(ts.createFunctionExpression(
+                /*modifiers*/ undefined, 
+                /*asteriskToken*/ undefined, 
+                /*name*/ undefined, 
+                /*typeParameters*/ undefined, [ts.createParameter(/*decorators*/ undefined, /*modifiers*/ undefined, /*dotDotDotToken*/ undefined, parameterName)], 
+                /*type*/ undefined, ts.createBlock(statements, /*multiLine*/ true)));
+            }
+            return ts.createArrayLiteral(setters, /*multiLine*/ true);
+        }
+        //
+        // Top-level Source Element Visitors
+        //
+        /**
+         * Visit source elements at the top-level of a module.
+         *
+         * @param node The node to visit.
+         */
+        function sourceElementVisitor(node) {
+            switch (node.kind) {
+                case 244 /* ImportDeclaration */:
+                    return visitImportDeclaration(node);
+                case 243 /* ImportEqualsDeclaration */:
+                    return visitImportEqualsDeclaration(node);
+                case 250 /* ExportDeclaration */:
+                    // ExportDeclarations are elided as they are handled via
+                    // `appendExportsOfDeclaration`.
+                    return undefined;
+                case 249 /* ExportAssignment */:
+                    return visitExportAssignment(node);
+                default:
+                    return nestedElementVisitor(node);
+            }
+        }
+        /**
+         * Visits an ImportDeclaration node.
+         *
+         * @param node The node to visit.
+         */
+        function visitImportDeclaration(node) {
+            var statements;
+            if (node.importClause) {
+                hoistVariableDeclaration(ts.getLocalNameForExternalImport(node, currentSourceFile)); // TODO: GH#18217
+            }
+            if (hasAssociatedEndOfDeclarationMarker(node)) {
+                // Defer exports until we encounter an EndOfDeclarationMarker node
+                var id = ts.getOriginalNodeId(node);
+                deferredExports[id] = appendExportsOfImportDeclaration(deferredExports[id], node);
+            }
+            else {
+                statements = appendExportsOfImportDeclaration(statements, node);
+            }
+            return ts.singleOrMany(statements);
+        }
+        /**
+         * Visits an ImportEqualsDeclaration node.
+         *
+         * @param node The node to visit.
+         */
+        function visitImportEqualsDeclaration(node) {
+            ts.Debug.assert(ts.isExternalModuleImportEqualsDeclaration(node), "import= for internal module references should be handled in an earlier transformer.");
+            var statements;
+            hoistVariableDeclaration(ts.getLocalNameForExternalImport(node, currentSourceFile)); // TODO: GH#18217
+            if (hasAssociatedEndOfDeclarationMarker(node)) {
+                // Defer exports until we encounter an EndOfDeclarationMarker node
+                var id = ts.getOriginalNodeId(node);
+                deferredExports[id] = appendExportsOfImportEqualsDeclaration(deferredExports[id], node);
+            }
+            else {
+                statements = appendExportsOfImportEqualsDeclaration(statements, node);
+            }
+            return ts.singleOrMany(statements);
+        }
+        /**
+         * Visits an ExportAssignment node.
+         *
+         * @param node The node to visit.
+         */
+        function visitExportAssignment(node) {
+            if (node.isExportEquals) {
+                // Elide `export=` as it is illegal in a SystemJS module.
+                return undefined;
+            }
+            var expression = ts.visitNode(node.expression, destructuringAndImportCallVisitor, ts.isExpression);
+            var original = node.original;
+            if (original && hasAssociatedEndOfDeclarationMarker(original)) {
+                // Defer exports until we encounter an EndOfDeclarationMarker node
+                var id = ts.getOriginalNodeId(node);
+                deferredExports[id] = appendExportStatement(deferredExports[id], ts.createIdentifier("default"), expression, /*allowComments*/ true);
+            }
+            else {
+                return createExportStatement(ts.createIdentifier("default"), expression, /*allowComments*/ true);
+            }
+        }
+        /**
+         * Visits a FunctionDeclaration, hoisting it to the outer module body function.
+         *
+         * @param node The node to visit.
+         */
+        function visitFunctionDeclaration(node) {
+            if (ts.hasModifier(node, 1 /* Export */)) {
+                hoistedStatements = ts.append(hoistedStatements, ts.updateFunctionDeclaration(node, node.decorators, ts.visitNodes(node.modifiers, modifierVisitor, ts.isModifier), node.asteriskToken, ts.getDeclarationName(node, /*allowComments*/ true, /*allowSourceMaps*/ true), 
+                /*typeParameters*/ undefined, ts.visitNodes(node.parameters, destructuringAndImportCallVisitor, ts.isParameterDeclaration), 
+                /*type*/ undefined, ts.visitNode(node.body, destructuringAndImportCallVisitor, ts.isBlock)));
+            }
+            else {
+                hoistedStatements = ts.append(hoistedStatements, ts.visitEachChild(node, destructuringAndImportCallVisitor, context));
+            }
+            if (hasAssociatedEndOfDeclarationMarker(node)) {
+                // Defer exports until we encounter an EndOfDeclarationMarker node
+                var id = ts.getOriginalNodeId(node);
+                deferredExports[id] = appendExportsOfHoistedDeclaration(deferredExports[id], node);
+            }
+            else {
+                hoistedStatements = appendExportsOfHoistedDeclaration(hoistedStatements, node);
+            }
+            return undefined;
+        }
+        /**
+         * Visits a ClassDeclaration, hoisting its name to the outer module body function.
+         *
+         * @param node The node to visit.
+         */
+        function visitClassDeclaration(node) {
+            var statements;
+            // Hoist the name of the class declaration to the outer module body function.
+            var name = ts.getLocalName(node);
+            hoistVariableDeclaration(name);
+            // Rewrite the class declaration into an assignment of a class expression.
+            statements = ts.append(statements, ts.setTextRange(ts.createStatement(ts.createAssignment(name, ts.setTextRange(ts.createClassExpression(
+            /*modifiers*/ undefined, node.name, 
+            /*typeParameters*/ undefined, ts.visitNodes(node.heritageClauses, destructuringAndImportCallVisitor, ts.isHeritageClause), ts.visitNodes(node.members, destructuringAndImportCallVisitor, ts.isClassElement)), node))), node));
+            if (hasAssociatedEndOfDeclarationMarker(node)) {
+                // Defer exports until we encounter an EndOfDeclarationMarker node
+                var id = ts.getOriginalNodeId(node);
+                deferredExports[id] = appendExportsOfHoistedDeclaration(deferredExports[id], node);
+            }
+            else {
+                statements = appendExportsOfHoistedDeclaration(statements, node);
+            }
+            return ts.singleOrMany(statements);
+        }
+        /**
+         * Visits a variable statement, hoisting declared names to the top-level module body.
+         * Each declaration is rewritten into an assignment expression.
+         *
+         * @param node The node to visit.
+         */
+        function visitVariableStatement(node) {
+            if (!shouldHoistVariableDeclarationList(node.declarationList)) {
+                return ts.visitNode(node, destructuringAndImportCallVisitor, ts.isStatement);
+            }
+            var expressions;
+            var isExportedDeclaration = ts.hasModifier(node, 1 /* Export */);
+            var isMarkedDeclaration = hasAssociatedEndOfDeclarationMarker(node);
+            for (var _i = 0, _a = node.declarationList.declarations; _i < _a.length; _i++) {
+                var variable = _a[_i];
+                if (variable.initializer) {
+                    expressions = ts.append(expressions, transformInitializedVariable(variable, isExportedDeclaration && !isMarkedDeclaration));
+                }
+                else {
+                    hoistBindingElement(variable);
+                }
+            }
+            var statements;
+            if (expressions) {
+                statements = ts.append(statements, ts.setTextRange(ts.createStatement(ts.inlineExpressions(expressions)), node));
+            }
+            if (isMarkedDeclaration) {
+                // Defer exports until we encounter an EndOfDeclarationMarker node
+                var id = ts.getOriginalNodeId(node);
+                deferredExports[id] = appendExportsOfVariableStatement(deferredExports[id], node, isExportedDeclaration);
+            }
+            else {
+                statements = appendExportsOfVariableStatement(statements, node, /*exportSelf*/ false);
+            }
+            return ts.singleOrMany(statements);
+        }
+        /**
+         * Hoists the declared names of a VariableDeclaration or BindingElement.
+         *
+         * @param node The declaration to hoist.
+         */
+        function hoistBindingElement(node) {
+            if (ts.isBindingPattern(node.name)) {
+                for (var _i = 0, _a = node.name.elements; _i < _a.length; _i++) {
+                    var element = _a[_i];
+                    if (!ts.isOmittedExpression(element)) {
+                        hoistBindingElement(element);
+                    }
+                }
+            }
+            else {
+                hoistVariableDeclaration(ts.getSynthesizedClone(node.name));
+            }
+        }
+        /**
+         * Determines whether a VariableDeclarationList should be hoisted.
+         *
+         * @param node The node to test.
+         */
+        function shouldHoistVariableDeclarationList(node) {
+            // hoist only non-block scoped declarations or block scoped declarations parented by source file
+            return (ts.getEmitFlags(node) & 2097152 /* NoHoisting */) === 0
+                && (enclosingBlockScopedContainer.kind === 274 /* SourceFile */
+                    || (ts.getOriginalNode(node).flags & 3 /* BlockScoped */) === 0);
+        }
+        /**
+         * Transform an initialized variable declaration into an expression.
+         *
+         * @param node The node to transform.
+         * @param isExportedDeclaration A value indicating whether the variable is exported.
+         */
+        function transformInitializedVariable(node, isExportedDeclaration) {
+            var createAssignment = isExportedDeclaration ? createExportedVariableAssignment : createNonExportedVariableAssignment;
+            return ts.isBindingPattern(node.name)
+                ? ts.flattenDestructuringAssignment(node, destructuringAndImportCallVisitor, context, 0 /* All */, 
+                /*needsValue*/ false, createAssignment)
+                : node.initializer ? createAssignment(node.name, ts.visitNode(node.initializer, destructuringAndImportCallVisitor, ts.isExpression)) : node.name;
+        }
+        /**
+         * Creates an assignment expression for an exported variable declaration.
+         *
+         * @param name The name of the variable.
+         * @param value The value of the variable's initializer.
+         * @param location The source map location for the assignment.
+         */
+        function createExportedVariableAssignment(name, value, location) {
+            return createVariableAssignment(name, value, location, /*isExportedDeclaration*/ true);
+        }
+        /**
+         * Creates an assignment expression for a non-exported variable declaration.
+         *
+         * @param name The name of the variable.
+         * @param value The value of the variable's initializer.
+         * @param location The source map location for the assignment.
+         */
+        function createNonExportedVariableAssignment(name, value, location) {
+            return createVariableAssignment(name, value, location, /*isExportedDeclaration*/ false);
+        }
+        /**
+         * Creates an assignment expression for a variable declaration.
+         *
+         * @param name The name of the variable.
+         * @param value The value of the variable's initializer.
+         * @param location The source map location for the assignment.
+         * @param isExportedDeclaration A value indicating whether the variable is exported.
+         */
+        function createVariableAssignment(name, value, location, isExportedDeclaration) {
+            hoistVariableDeclaration(ts.getSynthesizedClone(name));
+            return isExportedDeclaration
+                ? createExportExpression(name, preventSubstitution(ts.setTextRange(ts.createAssignment(name, value), location)))
+                : preventSubstitution(ts.setTextRange(ts.createAssignment(name, value), location));
+        }
+        /**
+         * Visits a MergeDeclarationMarker used as a placeholder for the beginning of a merged
+         * and transformed declaration.
+         *
+         * @param node The node to visit.
+         */
+        function visitMergeDeclarationMarker(node) {
+            // For an EnumDeclaration or ModuleDeclaration that merges with a preceeding
+            // declaration we do not emit a leading variable declaration. To preserve the
+            // begin/end semantics of the declararation and to properly handle exports
+            // we wrapped the leading variable declaration in a `MergeDeclarationMarker`.
+            //
+            // To balance the declaration, we defer the exports of the elided variable
+            // statement until we visit this declaration's `EndOfDeclarationMarker`.
+            if (hasAssociatedEndOfDeclarationMarker(node) && node.original.kind === 214 /* VariableStatement */) {
+                var id = ts.getOriginalNodeId(node);
+                var isExportedDeclaration = ts.hasModifier(node.original, 1 /* Export */);
+                deferredExports[id] = appendExportsOfVariableStatement(deferredExports[id], node.original, isExportedDeclaration);
+            }
+            return node;
+        }
+        /**
+         * Determines whether a node has an associated EndOfDeclarationMarker.
+         *
+         * @param node The node to test.
+         */
+        function hasAssociatedEndOfDeclarationMarker(node) {
+            return (ts.getEmitFlags(node) & 4194304 /* HasEndOfDeclarationMarker */) !== 0;
+        }
+        /**
+         * Visits a DeclarationMarker used as a placeholder for the end of a transformed
+         * declaration.
+         *
+         * @param node The node to visit.
+         */
+        function visitEndOfDeclarationMarker(node) {
+            // For some transformations we emit an `EndOfDeclarationMarker` to mark the actual
+            // end of the transformed declaration. We use this marker to emit any deferred exports
+            // of the declaration.
+            var id = ts.getOriginalNodeId(node);
+            var statements = deferredExports[id];
+            if (statements) {
+                delete deferredExports[id];
+                return ts.append(statements, node);
+            }
+            else {
+                var original = ts.getOriginalNode(node);
+                if (ts.isModuleOrEnumDeclaration(original)) {
+                    return ts.append(appendExportsOfDeclaration(statements, original), node);
+                }
+            }
+            return node;
+        }
+        /**
+         * Appends the exports of an ImportDeclaration to a statement list, returning the
+         * statement list.
+         *
+         * @param statements A statement list to which the down-level export statements are to be
+         * appended. If `statements` is `undefined`, a new array is allocated if statements are
+         * appended.
+         * @param decl The declaration whose exports are to be recorded.
+         */
+        function appendExportsOfImportDeclaration(statements, decl) {
+            if (moduleInfo.exportEquals) {
+                return statements;
+            }
+            var importClause = decl.importClause;
+            if (!importClause) {
+                return statements;
+            }
+            if (importClause.name) {
+                statements = appendExportsOfDeclaration(statements, importClause);
+            }
+            var namedBindings = importClause.namedBindings;
+            if (namedBindings) {
+                switch (namedBindings.kind) {
+                    case 246 /* NamespaceImport */:
+                        statements = appendExportsOfDeclaration(statements, namedBindings);
+                        break;
+                    case 247 /* NamedImports */:
+                        for (var _i = 0, _a = namedBindings.elements; _i < _a.length; _i++) {
+                            var importBinding = _a[_i];
+                            statements = appendExportsOfDeclaration(statements, importBinding);
+                        }
+                        break;
+                }
+            }
+            return statements;
+        }
+        /**
+         * Appends the export of an ImportEqualsDeclaration to a statement list, returning the
+         * statement list.
+         *
+         * @param statements A statement list to which the down-level export statements are to be
+         * appended. If `statements` is `undefined`, a new array is allocated if statements are
+         * appended.
+         * @param decl The declaration whose exports are to be recorded.
+         */
+        function appendExportsOfImportEqualsDeclaration(statements, decl) {
+            if (moduleInfo.exportEquals) {
+                return statements;
+            }
+            return appendExportsOfDeclaration(statements, decl);
+        }
+        /**
+         * Appends the exports of a VariableStatement to a statement list, returning the statement
+         * list.
+         *
+         * @param statements A statement list to which the down-level export statements are to be
+         * appended. If `statements` is `undefined`, a new array is allocated if statements are
+         * appended.
+         * @param node The VariableStatement whose exports are to be recorded.
+         * @param exportSelf A value indicating whether to also export each VariableDeclaration of
+         * `nodes` declaration list.
+         */
+        function appendExportsOfVariableStatement(statements, node, exportSelf) {
+            if (moduleInfo.exportEquals) {
+                return statements;
+            }
+            for (var _i = 0, _a = node.declarationList.declarations; _i < _a.length; _i++) {
+                var decl = _a[_i];
+                if (decl.initializer || exportSelf) {
+                    statements = appendExportsOfBindingElement(statements, decl, exportSelf);
+                }
+            }
+            return statements;
+        }
+        /**
+         * Appends the exports of a VariableDeclaration or BindingElement to a statement list,
+         * returning the statement list.
+         *
+         * @param statements A statement list to which the down-level export statements are to be
+         * appended. If `statements` is `undefined`, a new array is allocated if statements are
+         * appended.
+         * @param decl The declaration whose exports are to be recorded.
+         * @param exportSelf A value indicating whether to also export the declaration itself.
+         */
+        function appendExportsOfBindingElement(statements, decl, exportSelf) {
+            if (moduleInfo.exportEquals) {
+                return statements;
+            }
+            if (ts.isBindingPattern(decl.name)) {
+                for (var _i = 0, _a = decl.name.elements; _i < _a.length; _i++) {
+                    var element = _a[_i];
+                    if (!ts.isOmittedExpression(element)) {
+                        statements = appendExportsOfBindingElement(statements, element, exportSelf);
+                    }
+                }
+            }
+            else if (!ts.isGeneratedIdentifier(decl.name)) {
+                var excludeName = void 0;
+                if (exportSelf) {
+                    statements = appendExportStatement(statements, decl.name, ts.getLocalName(decl));
+                    excludeName = ts.idText(decl.name);
+                }
+                statements = appendExportsOfDeclaration(statements, decl, excludeName);
+            }
+            return statements;
+        }
+        /**
+         * Appends the exports of a ClassDeclaration or FunctionDeclaration to a statement list,
+         * returning the statement list.
+         *
+         * @param statements A statement list to which the down-level export statements are to be
+         * appended. If `statements` is `undefined`, a new array is allocated if statements are
+         * appended.
+         * @param decl The declaration whose exports are to be recorded.
+         */
+        function appendExportsOfHoistedDeclaration(statements, decl) {
+            if (moduleInfo.exportEquals) {
+                return statements;
+            }
+            var excludeName;
+            if (ts.hasModifier(decl, 1 /* Export */)) {
+                var exportName = ts.hasModifier(decl, 512 /* Default */) ? ts.createLiteral("default") : decl.name;
+                statements = appendExportStatement(statements, exportName, ts.getLocalName(decl));
+                excludeName = ts.getTextOfIdentifierOrLiteral(exportName);
+            }
+            if (decl.name) {
+                statements = appendExportsOfDeclaration(statements, decl, excludeName);
+            }
+            return statements;
+        }
+        /**
+         * Appends the exports of a declaration to a statement list, returning the statement list.
+         *
+         * @param statements A statement list to which the down-level export statements are to be
+         * appended. If `statements` is `undefined`, a new array is allocated if statements are
+         * appended.
+         * @param decl The declaration to export.
+         * @param excludeName An optional name to exclude from exports.
+         */
+        function appendExportsOfDeclaration(statements, decl, excludeName) {
+            if (moduleInfo.exportEquals) {
+                return statements;
+            }
+            var name = ts.getDeclarationName(decl);
+            var exportSpecifiers = moduleInfo.exportSpecifiers.get(ts.idText(name));
+            if (exportSpecifiers) {
+                for (var _i = 0, exportSpecifiers_2 = exportSpecifiers; _i < exportSpecifiers_2.length; _i++) {
+                    var exportSpecifier = exportSpecifiers_2[_i];
+                    if (exportSpecifier.name.escapedText !== excludeName) {
+                        statements = appendExportStatement(statements, exportSpecifier.name, name);
+                    }
+                }
+            }
+            return statements;
+        }
+        /**
+         * Appends the down-level representation of an export to a statement list, returning the
+         * statement list.
+         *
+         * @param statements A statement list to which the down-level export statements are to be
+         * appended. If `statements` is `undefined`, a new array is allocated if statements are
+         * appended.
+         * @param exportName The name of the export.
+         * @param expression The expression to export.
+         * @param allowComments Whether to allow comments on the export.
+         */
+        function appendExportStatement(statements, exportName, expression, allowComments) {
+            statements = ts.append(statements, createExportStatement(exportName, expression, allowComments));
+            return statements;
+        }
+        /**
+         * Creates a call to the current file's export function to export a value.
+         *
+         * @param name The bound name of the export.
+         * @param value The exported value.
+         * @param allowComments An optional value indicating whether to emit comments for the statement.
+         */
+        function createExportStatement(name, value, allowComments) {
+            var statement = ts.createStatement(createExportExpression(name, value));
+            ts.startOnNewLine(statement);
+            if (!allowComments) {
+                ts.setEmitFlags(statement, 1536 /* NoComments */);
+            }
+            return statement;
+        }
+        /**
+         * Creates a call to the current file's export function to export a value.
+         *
+         * @param name The bound name of the export.
+         * @param value The exported value.
+         */
+        function createExportExpression(name, value) {
+            var exportName = ts.isIdentifier(name) ? ts.createLiteral(name) : name;
+            ts.setEmitFlags(value, ts.getEmitFlags(value) | 1536 /* NoComments */);
+            return ts.setCommentRange(ts.createCall(exportFunction, /*typeArguments*/ undefined, [exportName, value]), value);
+        }
+        //
+        // Top-Level or Nested Source Element Visitors
+        //
+        /**
+         * Visit nested elements at the top-level of a module.
+         *
+         * @param node The node to visit.
+         */
+        function nestedElementVisitor(node) {
+            switch (node.kind) {
+                case 214 /* VariableStatement */:
+                    return visitVariableStatement(node);
+                case 234 /* FunctionDeclaration */:
+                    return visitFunctionDeclaration(node);
+                case 235 /* ClassDeclaration */:
+                    return visitClassDeclaration(node);
+                case 220 /* ForStatement */:
+                    return visitForStatement(node);
+                case 221 /* ForInStatement */:
+                    return visitForInStatement(node);
+                case 222 /* ForOfStatement */:
+                    return visitForOfStatement(node);
+                case 218 /* DoStatement */:
+                    return visitDoStatement(node);
+                case 219 /* WhileStatement */:
+                    return visitWhileStatement(node);
+                case 228 /* LabeledStatement */:
+                    return visitLabeledStatement(node);
+                case 226 /* WithStatement */:
+                    return visitWithStatement(node);
+                case 227 /* SwitchStatement */:
+                    return visitSwitchStatement(node);
+                case 241 /* CaseBlock */:
+                    return visitCaseBlock(node);
+                case 266 /* CaseClause */:
+                    return visitCaseClause(node);
+                case 267 /* DefaultClause */:
+                    return visitDefaultClause(node);
+                case 230 /* TryStatement */:
+                    return visitTryStatement(node);
+                case 269 /* CatchClause */:
+                    return visitCatchClause(node);
+                case 213 /* Block */:
+                    return visitBlock(node);
+                case 303 /* MergeDeclarationMarker */:
+                    return visitMergeDeclarationMarker(node);
+                case 304 /* EndOfDeclarationMarker */:
+                    return visitEndOfDeclarationMarker(node);
+                default:
+                    return destructuringAndImportCallVisitor(node);
+            }
+        }
+        /**
+         * Visits the body of a ForStatement to hoist declarations.
+         *
+         * @param node The node to visit.
+         */
+        function visitForStatement(node) {
+            var savedEnclosingBlockScopedContainer = enclosingBlockScopedContainer;
+            enclosingBlockScopedContainer = node;
+            node = ts.updateFor(node, node.initializer && visitForInitializer(node.initializer), ts.visitNode(node.condition, destructuringAndImportCallVisitor, ts.isExpression), ts.visitNode(node.incrementor, destructuringAndImportCallVisitor, ts.isExpression), ts.visitNode(node.statement, nestedElementVisitor, ts.isStatement));
+            enclosingBlockScopedContainer = savedEnclosingBlockScopedContainer;
+            return node;
+        }
+        /**
+         * Visits the body of a ForInStatement to hoist declarations.
+         *
+         * @param node The node to visit.
+         */
+        function visitForInStatement(node) {
+            var savedEnclosingBlockScopedContainer = enclosingBlockScopedContainer;
+            enclosingBlockScopedContainer = node;
+            node = ts.updateForIn(node, visitForInitializer(node.initializer), ts.visitNode(node.expression, destructuringAndImportCallVisitor, ts.isExpression), ts.visitNode(node.statement, nestedElementVisitor, ts.isStatement, ts.liftToBlock));
+            enclosingBlockScopedContainer = savedEnclosingBlockScopedContainer;
+            return node;
+        }
+        /**
+         * Visits the body of a ForOfStatement to hoist declarations.
+         *
+         * @param node The node to visit.
+         */
+        function visitForOfStatement(node) {
+            var savedEnclosingBlockScopedContainer = enclosingBlockScopedContainer;
+            enclosingBlockScopedContainer = node;
+            node = ts.updateForOf(node, node.awaitModifier, visitForInitializer(node.initializer), ts.visitNode(node.expression, destructuringAndImportCallVisitor, ts.isExpression), ts.visitNode(node.statement, nestedElementVisitor, ts.isStatement, ts.liftToBlock));
+            enclosingBlockScopedContainer = savedEnclosingBlockScopedContainer;
+            return node;
+        }
+        /**
+         * Determines whether to hoist the initializer of a ForStatement, ForInStatement, or
+         * ForOfStatement.
+         *
+         * @param node The node to test.
+         */
+        function shouldHoistForInitializer(node) {
+            return ts.isVariableDeclarationList(node)
+                && shouldHoistVariableDeclarationList(node);
+        }
+        /**
+         * Visits the initializer of a ForStatement, ForInStatement, or ForOfStatement
+         *
+         * @param node The node to visit.
+         */
+        function visitForInitializer(node) {
+            if (shouldHoistForInitializer(node)) {
+                var expressions = void 0;
+                for (var _i = 0, _a = node.declarations; _i < _a.length; _i++) {
+                    var variable = _a[_i];
+                    expressions = ts.append(expressions, transformInitializedVariable(variable, /*isExportedDeclaration*/ false));
+                    if (!variable.initializer) {
+                        hoistBindingElement(variable);
+                    }
+                }
+                return expressions ? ts.inlineExpressions(expressions) : ts.createOmittedExpression();
+            }
+            else {
+                return ts.visitEachChild(node, nestedElementVisitor, context);
+            }
+        }
+        /**
+         * Visits the body of a DoStatement to hoist declarations.
+         *
+         * @param node The node to visit.
+         */
+        function visitDoStatement(node) {
+            return ts.updateDo(node, ts.visitNode(node.statement, nestedElementVisitor, ts.isStatement, ts.liftToBlock), ts.visitNode(node.expression, destructuringAndImportCallVisitor, ts.isExpression));
+        }
+        /**
+         * Visits the body of a WhileStatement to hoist declarations.
+         *
+         * @param node The node to visit.
+         */
+        function visitWhileStatement(node) {
+            return ts.updateWhile(node, ts.visitNode(node.expression, destructuringAndImportCallVisitor, ts.isExpression), ts.visitNode(node.statement, nestedElementVisitor, ts.isStatement, ts.liftToBlock));
+        }
+        /**
+         * Visits the body of a LabeledStatement to hoist declarations.
+         *
+         * @param node The node to visit.
+         */
+        function visitLabeledStatement(node) {
+            return ts.updateLabel(node, node.label, ts.visitNode(node.statement, nestedElementVisitor, ts.isStatement, ts.liftToBlock));
+        }
+        /**
+         * Visits the body of a WithStatement to hoist declarations.
+         *
+         * @param node The node to visit.
+         */
+        function visitWithStatement(node) {
+            return ts.updateWith(node, ts.visitNode(node.expression, destructuringAndImportCallVisitor, ts.isExpression), ts.visitNode(node.statement, nestedElementVisitor, ts.isStatement, ts.liftToBlock));
+        }
+        /**
+         * Visits the body of a SwitchStatement to hoist declarations.
+         *
+         * @param node The node to visit.
+         */
+        function visitSwitchStatement(node) {
+            return ts.updateSwitch(node, ts.visitNode(node.expression, destructuringAndImportCallVisitor, ts.isExpression), ts.visitNode(node.caseBlock, nestedElementVisitor, ts.isCaseBlock));
+        }
+        /**
+         * Visits the body of a CaseBlock to hoist declarations.
+         *
+         * @param node The node to visit.
+         */
+        function visitCaseBlock(node) {
+            var savedEnclosingBlockScopedContainer = enclosingBlockScopedContainer;
+            enclosingBlockScopedContainer = node;
+            node = ts.updateCaseBlock(node, ts.visitNodes(node.clauses, nestedElementVisitor, ts.isCaseOrDefaultClause));
+            enclosingBlockScopedContainer = savedEnclosingBlockScopedContainer;
+            return node;
+        }
+        /**
+         * Visits the body of a CaseClause to hoist declarations.
+         *
+         * @param node The node to visit.
+         */
+        function visitCaseClause(node) {
+            return ts.updateCaseClause(node, ts.visitNode(node.expression, destructuringAndImportCallVisitor, ts.isExpression), ts.visitNodes(node.statements, nestedElementVisitor, ts.isStatement));
+        }
+        /**
+         * Visits the body of a DefaultClause to hoist declarations.
+         *
+         * @param node The node to visit.
+         */
+        function visitDefaultClause(node) {
+            return ts.visitEachChild(node, nestedElementVisitor, context);
+        }
+        /**
+         * Visits the body of a TryStatement to hoist declarations.
+         *
+         * @param node The node to visit.
+         */
+        function visitTryStatement(node) {
+            return ts.visitEachChild(node, nestedElementVisitor, context);
+        }
+        /**
+         * Visits the body of a CatchClause to hoist declarations.
+         *
+         * @param node The node to visit.
+         */
+        function visitCatchClause(node) {
+            var savedEnclosingBlockScopedContainer = enclosingBlockScopedContainer;
+            enclosingBlockScopedContainer = node;
+            node = ts.updateCatchClause(node, node.variableDeclaration, ts.visitNode(node.block, nestedElementVisitor, ts.isBlock));
+            enclosingBlockScopedContainer = savedEnclosingBlockScopedContainer;
+            return node;
+        }
+        /**
+         * Visits the body of a Block to hoist declarations.
+         *
+         * @param node The node to visit.
+         */
+        function visitBlock(node) {
+            var savedEnclosingBlockScopedContainer = enclosingBlockScopedContainer;
+            enclosingBlockScopedContainer = node;
+            node = ts.visitEachChild(node, nestedElementVisitor, context);
+            enclosingBlockScopedContainer = savedEnclosingBlockScopedContainer;
+            return node;
+        }
+        //
+        // Destructuring Assignment Visitors
+        //
+        /**
+         * Visit nodes to flatten destructuring assignments to exported symbols.
+         *
+         * @param node The node to visit.
+         */
+        function destructuringAndImportCallVisitor(node) {
+            if (node.transformFlags & 1024 /* DestructuringAssignment */
+                && node.kind === 200 /* BinaryExpression */) {
+                return visitDestructuringAssignment(node);
+            }
+            else if (ts.isImportCall(node)) {
+                return visitImportCallExpression(node);
+            }
+            else if ((node.transformFlags & 2048 /* ContainsDestructuringAssignment */) || (node.transformFlags & 67108864 /* ContainsDynamicImport */)) {
+                return ts.visitEachChild(node, destructuringAndImportCallVisitor, context);
+            }
+            else {
+                return node;
+            }
+        }
+        function visitImportCallExpression(node) {
+            // import("./blah")
+            // emit as
+            // System.register([], function (_export, _context) {
+            //     return {
+            //         setters: [],
+            //         execute: () => {
+            //             _context.import('./blah');
+            //         }
+            //     };
+            // });
+            return ts.createCall(ts.createPropertyAccess(contextObject, ts.createIdentifier("import")), 
+            /*typeArguments*/ undefined, ts.some(node.arguments) ? [ts.visitNode(node.arguments[0], destructuringAndImportCallVisitor)] : []);
+        }
+        /**
+         * Visits a DestructuringAssignment to flatten destructuring to exported symbols.
+         *
+         * @param node The node to visit.
+         */
+        function visitDestructuringAssignment(node) {
+            if (hasExportedReferenceInDestructuringTarget(node.left)) {
+                return ts.flattenDestructuringAssignment(node, destructuringAndImportCallVisitor, context, 0 /* All */, 
+                /*needsValue*/ true);
+            }
+            return ts.visitEachChild(node, destructuringAndImportCallVisitor, context);
+        }
+        /**
+         * Determines whether the target of a destructuring assigment refers to an exported symbol.
+         *
+         * @param node The destructuring target.
+         */
+        function hasExportedReferenceInDestructuringTarget(node) {
+            if (ts.isAssignmentExpression(node, /*excludeCompoundAssignment*/ true)) {
+                return hasExportedReferenceInDestructuringTarget(node.left);
+            }
+            else if (ts.isSpreadElement(node)) {
+                return hasExportedReferenceInDestructuringTarget(node.expression);
+            }
+            else if (ts.isObjectLiteralExpression(node)) {
+                return ts.some(node.properties, hasExportedReferenceInDestructuringTarget);
+            }
+            else if (ts.isArrayLiteralExpression(node)) {
+                return ts.some(node.elements, hasExportedReferenceInDestructuringTarget);
+            }
+            else if (ts.isShorthandPropertyAssignment(node)) {
+                return hasExportedReferenceInDestructuringTarget(node.name);
+            }
+            else if (ts.isPropertyAssignment(node)) {
+                return hasExportedReferenceInDestructuringTarget(node.initializer);
+            }
+            else if (ts.isIdentifier(node)) {
+                var container = resolver.getReferencedExportContainer(node);
+                return container !== undefined && container.kind === 274 /* SourceFile */;
+            }
+            else {
+                return false;
+            }
+        }
+        //
+        // Modifier Visitors
+        //
+        /**
+         * Visit nodes to elide module-specific modifiers.
+         *
+         * @param node The node to visit.
+         */
+        function modifierVisitor(node) {
+            switch (node.kind) {
+                case 84 /* ExportKeyword */:
+                case 79 /* DefaultKeyword */:
+                    return undefined;
+            }
+            return node;
+        }
+        //
+        // Emit Notification
+        //
+        /**
+         * Hook for node emit notifications.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to emit.
+         * @param emitCallback A callback used to emit the node in the printer.
+         */
+        function onEmitNode(hint, node, emitCallback) {
+            if (node.kind === 274 /* SourceFile */) {
+                var id = ts.getOriginalNodeId(node);
+                currentSourceFile = node;
+                moduleInfo = moduleInfoMap[id];
+                exportFunction = exportFunctionsMap[id];
+                noSubstitution = noSubstitutionMap[id];
+                if (noSubstitution) {
+                    delete noSubstitutionMap[id];
+                }
+                previousOnEmitNode(hint, node, emitCallback);
+                currentSourceFile = undefined;
+                moduleInfo = undefined;
+                exportFunction = undefined;
+                noSubstitution = undefined;
+            }
+            else {
+                previousOnEmitNode(hint, node, emitCallback);
+            }
+        }
+        //
+        // Substitutions
+        //
+        /**
+         * Hooks node substitutions.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to substitute.
+         */
+        function onSubstituteNode(hint, node) {
+            node = previousOnSubstituteNode(hint, node);
+            if (isSubstitutionPrevented(node)) {
+                return node;
+            }
+            if (hint === 1 /* Expression */) {
+                return substituteExpression(node);
+            }
+            else if (hint === 4 /* Unspecified */) {
+                return substituteUnspecified(node);
+            }
+            return node;
+        }
+        /**
+         * Substitute the node, if necessary.
+         *
+         * @param node The node to substitute.
+         */
+        function substituteUnspecified(node) {
+            switch (node.kind) {
+                case 271 /* ShorthandPropertyAssignment */:
+                    return substituteShorthandPropertyAssignment(node);
+            }
+            return node;
+        }
+        /**
+         * Substitution for a ShorthandPropertyAssignment whose name that may contain an imported or exported symbol.
+         *
+         * @param node The node to substitute.
+         */
+        function substituteShorthandPropertyAssignment(node) {
+            var name = node.name;
+            if (!ts.isGeneratedIdentifier(name) && !ts.isLocalName(name)) {
+                var importDeclaration = resolver.getReferencedImportDeclaration(name);
+                if (importDeclaration) {
+                    if (ts.isImportClause(importDeclaration)) {
+                        return ts.setTextRange(ts.createPropertyAssignment(ts.getSynthesizedClone(name), ts.createPropertyAccess(ts.getGeneratedNameForNode(importDeclaration.parent), ts.createIdentifier("default"))), 
+                        /*location*/ node);
+                    }
+                    else if (ts.isImportSpecifier(importDeclaration)) {
+                        return ts.setTextRange(ts.createPropertyAssignment(ts.getSynthesizedClone(name), ts.createPropertyAccess(ts.getGeneratedNameForNode(importDeclaration.parent.parent.parent), ts.getSynthesizedClone(importDeclaration.propertyName || importDeclaration.name))), 
+                        /*location*/ node);
+                    }
+                }
+            }
+            return node;
+        }
+        /**
+         * Substitute the expression, if necessary.
+         *
+         * @param node The node to substitute.
+         */
+        function substituteExpression(node) {
+            switch (node.kind) {
+                case 71 /* Identifier */:
+                    return substituteExpressionIdentifier(node);
+                case 200 /* BinaryExpression */:
+                    return substituteBinaryExpression(node);
+                case 198 /* PrefixUnaryExpression */:
+                case 199 /* PostfixUnaryExpression */:
+                    return substituteUnaryExpression(node);
+            }
+            return node;
+        }
+        /**
+         * Substitution for an Identifier expression that may contain an imported or exported symbol.
+         *
+         * @param node The node to substitute.
+         */
+        function substituteExpressionIdentifier(node) {
+            if (ts.getEmitFlags(node) & 4096 /* HelperName */) {
+                var externalHelpersModuleName = ts.getExternalHelpersModuleName(currentSourceFile);
+                if (externalHelpersModuleName) {
+                    return ts.createPropertyAccess(externalHelpersModuleName, node);
+                }
+                return node;
+            }
+            // When we see an identifier in an expression position that
+            // points to an imported symbol, we should substitute a qualified
+            // reference to the imported symbol if one is needed.
+            //
+            // - We do not substitute generated identifiers for any reason.
+            // - We do not substitute identifiers tagged with the LocalName flag.
+            if (!ts.isGeneratedIdentifier(node) && !ts.isLocalName(node)) {
+                var importDeclaration = resolver.getReferencedImportDeclaration(node);
+                if (importDeclaration) {
+                    if (ts.isImportClause(importDeclaration)) {
+                        return ts.setTextRange(ts.createPropertyAccess(ts.getGeneratedNameForNode(importDeclaration.parent), ts.createIdentifier("default")), 
+                        /*location*/ node);
+                    }
+                    else if (ts.isImportSpecifier(importDeclaration)) {
+                        return ts.setTextRange(ts.createPropertyAccess(ts.getGeneratedNameForNode(importDeclaration.parent.parent.parent), ts.getSynthesizedClone(importDeclaration.propertyName || importDeclaration.name)), 
+                        /*location*/ node);
+                    }
+                }
+            }
+            return node;
+        }
+        /**
+         * Substitution for a BinaryExpression that may contain an imported or exported symbol.
+         *
+         * @param node The node to substitute.
+         */
+        function substituteBinaryExpression(node) {
+            // When we see an assignment expression whose left-hand side is an exported symbol,
+            // we should ensure all exports of that symbol are updated with the correct value.
+            //
+            // - We do not substitute generated identifiers for any reason.
+            // - We do not substitute identifiers tagged with the LocalName flag.
+            // - We do not substitute identifiers that were originally the name of an enum or
+            //   namespace due to how they are transformed in TypeScript.
+            // - We only substitute identifiers that are exported at the top level.
+            if (ts.isAssignmentOperator(node.operatorToken.kind)
+                && ts.isIdentifier(node.left)
+                && !ts.isGeneratedIdentifier(node.left)
+                && !ts.isLocalName(node.left)
+                && !ts.isDeclarationNameOfEnumOrNamespace(node.left)) {
+                var exportedNames = getExports(node.left);
+                if (exportedNames) {
+                    // For each additional export of the declaration, apply an export assignment.
+                    var expression = node;
+                    for (var _i = 0, exportedNames_4 = exportedNames; _i < exportedNames_4.length; _i++) {
+                        var exportName = exportedNames_4[_i];
+                        expression = createExportExpression(exportName, preventSubstitution(expression));
+                    }
+                    return expression;
+                }
+            }
+            return node;
+        }
+        /**
+         * Substitution for a UnaryExpression that may contain an imported or exported symbol.
+         *
+         * @param node The node to substitute.
+         */
+        function substituteUnaryExpression(node) {
+            // When we see a prefix or postfix increment expression whose operand is an exported
+            // symbol, we should ensure all exports of that symbol are updated with the correct
+            // value.
+            //
+            // - We do not substitute generated identifiers for any reason.
+            // - We do not substitute identifiers tagged with the LocalName flag.
+            // - We do not substitute identifiers that were originally the name of an enum or
+            //   namespace due to how they are transformed in TypeScript.
+            // - We only substitute identifiers that are exported at the top level.
+            if ((node.operator === 43 /* PlusPlusToken */ || node.operator === 44 /* MinusMinusToken */)
+                && ts.isIdentifier(node.operand)
+                && !ts.isGeneratedIdentifier(node.operand)
+                && !ts.isLocalName(node.operand)
+                && !ts.isDeclarationNameOfEnumOrNamespace(node.operand)) {
+                var exportedNames = getExports(node.operand);
+                if (exportedNames) {
+                    var expression = node.kind === 199 /* PostfixUnaryExpression */
+                        ? ts.setTextRange(ts.createPrefix(node.operator, node.operand), node)
+                        : node;
+                    for (var _i = 0, exportedNames_5 = exportedNames; _i < exportedNames_5.length; _i++) {
+                        var exportName = exportedNames_5[_i];
+                        expression = createExportExpression(exportName, preventSubstitution(expression));
+                    }
+                    if (node.kind === 199 /* PostfixUnaryExpression */) {
+                        expression = node.operator === 43 /* PlusPlusToken */
+                            ? ts.createSubtract(preventSubstitution(expression), ts.createLiteral(1))
+                            : ts.createAdd(preventSubstitution(expression), ts.createLiteral(1));
+                    }
+                    return expression;
+                }
+            }
+            return node;
+        }
+        /**
+         * Gets the exports of a name.
+         *
+         * @param name The name.
+         */
+        function getExports(name) {
+            var exportedNames;
+            if (!ts.isGeneratedIdentifier(name)) {
+                var valueDeclaration = resolver.getReferencedImportDeclaration(name)
+                    || resolver.getReferencedValueDeclaration(name);
+                if (valueDeclaration) {
+                    var exportContainer = resolver.getReferencedExportContainer(name, /*prefixLocals*/ false);
+                    if (exportContainer && exportContainer.kind === 274 /* SourceFile */) {
+                        exportedNames = ts.append(exportedNames, ts.getDeclarationName(valueDeclaration));
+                    }
+                    exportedNames = ts.addRange(exportedNames, moduleInfo && moduleInfo.exportedBindings[ts.getOriginalNodeId(valueDeclaration)]);
+                }
+            }
+            return exportedNames;
+        }
+        /**
+         * Prevent substitution of a node for this transformer.
+         *
+         * @param node The node which should not be substituted.
+         */
+        function preventSubstitution(node) {
+            if (noSubstitution === undefined)
+                noSubstitution = [];
+            noSubstitution[ts.getNodeId(node)] = true;
+            return node;
+        }
+        /**
+         * Determines whether a node should not be substituted.
+         *
+         * @param node The node to test.
+         */
+        function isSubstitutionPrevented(node) {
+            return noSubstitution && node.id && noSubstitution[node.id];
+        }
+    }
+    ts.transformSystemModule = transformSystemModule;
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    function transformES2015Module(context) {
+        var compilerOptions = context.getCompilerOptions();
+        var previousOnEmitNode = context.onEmitNode;
+        var previousOnSubstituteNode = context.onSubstituteNode;
+        context.onEmitNode = onEmitNode;
+        context.onSubstituteNode = onSubstituteNode;
+        context.enableEmitNotification(274 /* SourceFile */);
+        context.enableSubstitution(71 /* Identifier */);
+        var currentSourceFile;
+        return ts.chainBundle(transformSourceFile);
+        function transformSourceFile(node) {
+            if (node.isDeclarationFile) {
+                return node;
+            }
+            if (ts.isExternalModule(node) || compilerOptions.isolatedModules) {
+                var externalHelpersModuleName = ts.getOrCreateExternalHelpersModuleNameIfNeeded(node, compilerOptions);
+                if (externalHelpersModuleName) {
+                    var statements = [];
+                    var statementOffset = ts.addPrologue(statements, node.statements);
+                    var tslibImport = ts.createImportDeclaration(
+                    /*decorators*/ undefined, 
+                    /*modifiers*/ undefined, ts.createImportClause(/*name*/ undefined, ts.createNamespaceImport(externalHelpersModuleName)), ts.createLiteral(ts.externalHelpersModuleNameText));
+                    ts.addEmitFlags(tslibImport, 67108864 /* NeverApplyImportHelper */);
+                    ts.append(statements, tslibImport);
+                    ts.addRange(statements, ts.visitNodes(node.statements, visitor, ts.isStatement, statementOffset));
+                    return ts.updateSourceFileNode(node, ts.setTextRange(ts.createNodeArray(statements), node.statements));
+                }
+                else {
+                    return ts.visitEachChild(node, visitor, context);
+                }
+            }
+            return node;
+        }
+        function visitor(node) {
+            switch (node.kind) {
+                case 243 /* ImportEqualsDeclaration */:
+                    // Elide `import=` as it is not legal with --module ES6
+                    return undefined;
+                case 249 /* ExportAssignment */:
+                    return visitExportAssignment(node);
+            }
+            return node;
+        }
+        function visitExportAssignment(node) {
+            // Elide `export=` as it is not legal with --module ES6
+            return node.isExportEquals ? undefined : node;
+        }
+        //
+        // Emit Notification
+        //
+        /**
+         * Hook for node emit.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to emit.
+         * @param emit A callback used to emit the node in the printer.
+         */
+        function onEmitNode(hint, node, emitCallback) {
+            if (ts.isSourceFile(node)) {
+                currentSourceFile = node;
+                previousOnEmitNode(hint, node, emitCallback);
+                currentSourceFile = undefined;
+            }
+            else {
+                previousOnEmitNode(hint, node, emitCallback);
+            }
+        }
+        //
+        // Substitutions
+        //
+        /**
+         * Hooks node substitutions.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to substitute.
+         */
+        function onSubstituteNode(hint, node) {
+            node = previousOnSubstituteNode(hint, node);
+            if (ts.isIdentifier(node) && hint === 1 /* Expression */) {
+                return substituteExpressionIdentifier(node);
+            }
+            return node;
+        }
+        function substituteExpressionIdentifier(node) {
+            if (ts.getEmitFlags(node) & 4096 /* HelperName */) {
+                var externalHelpersModuleName = ts.getExternalHelpersModuleName(currentSourceFile);
+                if (externalHelpersModuleName) {
+                    return ts.createPropertyAccess(externalHelpersModuleName, node);
+                }
+            }
+            return node;
+        }
+    }
+    ts.transformES2015Module = transformES2015Module;
+})(ts || (ts = {}));
+/* @internal */
+var ts;
+(function (ts) {
+    function canProduceDiagnostics(node) {
+        return ts.isVariableDeclaration(node) ||
+            ts.isPropertyDeclaration(node) ||
+            ts.isPropertySignature(node) ||
+            ts.isBindingElement(node) ||
+            ts.isSetAccessor(node) ||
+            ts.isGetAccessor(node) ||
+            ts.isConstructSignatureDeclaration(node) ||
+            ts.isCallSignatureDeclaration(node) ||
+            ts.isMethodDeclaration(node) ||
+            ts.isMethodSignature(node) ||
+            ts.isFunctionDeclaration(node) ||
+            ts.isParameter(node) ||
+            ts.isTypeParameterDeclaration(node) ||
+            ts.isExpressionWithTypeArguments(node) ||
+            ts.isImportEqualsDeclaration(node) ||
+            ts.isTypeAliasDeclaration(node) ||
+            ts.isConstructorDeclaration(node) ||
+            ts.isIndexSignatureDeclaration(node);
+    }
+    ts.canProduceDiagnostics = canProduceDiagnostics;
+    function createGetSymbolAccessibilityDiagnosticForNodeName(node) {
+        if (ts.isSetAccessor(node) || ts.isGetAccessor(node)) {
+            return getAccessorNameVisibilityError;
+        }
+        else if (ts.isMethodSignature(node) || ts.isMethodDeclaration(node)) {
+            return getMethodNameVisibilityError;
+        }
+        else {
+            return createGetSymbolAccessibilityDiagnosticForNode(node);
+        }
+        function getAccessorNameVisibilityError(symbolAccessibilityResult) {
+            var diagnosticMessage = getAccessorNameVisibilityDiagnosticMessage(symbolAccessibilityResult);
+            return diagnosticMessage !== undefined ? {
+                diagnosticMessage: diagnosticMessage,
+                errorNode: node,
+                typeName: node.name
+            } : undefined;
+        }
+        function getAccessorNameVisibilityDiagnosticMessage(symbolAccessibilityResult) {
+            if (ts.hasModifier(node, 32 /* Static */)) {
+                return symbolAccessibilityResult.errorModuleName ?
+                    symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                        ts.Diagnostics.Public_static_property_0_of_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :
+                        ts.Diagnostics.Public_static_property_0_of_exported_class_has_or_is_using_name_1_from_private_module_2 :
+                    ts.Diagnostics.Public_static_property_0_of_exported_class_has_or_is_using_private_name_1;
+            }
+            else if (node.parent.kind === 235 /* ClassDeclaration */) {
+                return symbolAccessibilityResult.errorModuleName ?
+                    symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                        ts.Diagnostics.Public_property_0_of_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :
+                        ts.Diagnostics.Public_property_0_of_exported_class_has_or_is_using_name_1_from_private_module_2 :
+                    ts.Diagnostics.Public_property_0_of_exported_class_has_or_is_using_private_name_1;
+            }
+            else {
+                return symbolAccessibilityResult.errorModuleName ?
+                    ts.Diagnostics.Property_0_of_exported_interface_has_or_is_using_name_1_from_private_module_2 :
+                    ts.Diagnostics.Property_0_of_exported_interface_has_or_is_using_private_name_1;
+            }
+        }
+        function getMethodNameVisibilityError(symbolAccessibilityResult) {
+            var diagnosticMessage = getMethodNameVisibilityDiagnosticMessage(symbolAccessibilityResult);
+            return diagnosticMessage !== undefined ? {
+                diagnosticMessage: diagnosticMessage,
+                errorNode: node,
+                typeName: node.name
+            } : undefined;
+        }
+        function getMethodNameVisibilityDiagnosticMessage(symbolAccessibilityResult) {
+            if (ts.hasModifier(node, 32 /* Static */)) {
+                return symbolAccessibilityResult.errorModuleName ?
+                    symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                        ts.Diagnostics.Public_static_method_0_of_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :
+                        ts.Diagnostics.Public_static_method_0_of_exported_class_has_or_is_using_name_1_from_private_module_2 :
+                    ts.Diagnostics.Public_static_method_0_of_exported_class_has_or_is_using_private_name_1;
+            }
+            else if (node.parent.kind === 235 /* ClassDeclaration */) {
+                return symbolAccessibilityResult.errorModuleName ?
+                    symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                        ts.Diagnostics.Public_method_0_of_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :
+                        ts.Diagnostics.Public_method_0_of_exported_class_has_or_is_using_name_1_from_private_module_2 :
+                    ts.Diagnostics.Public_method_0_of_exported_class_has_or_is_using_private_name_1;
+            }
+            else {
+                return symbolAccessibilityResult.errorModuleName ?
+                    ts.Diagnostics.Method_0_of_exported_interface_has_or_is_using_name_1_from_private_module_2 :
+                    ts.Diagnostics.Method_0_of_exported_interface_has_or_is_using_private_name_1;
+            }
+        }
+    }
+    ts.createGetSymbolAccessibilityDiagnosticForNodeName = createGetSymbolAccessibilityDiagnosticForNodeName;
+    function createGetSymbolAccessibilityDiagnosticForNode(node) {
+        if (ts.isVariableDeclaration(node) || ts.isPropertyDeclaration(node) || ts.isPropertySignature(node) || ts.isBindingElement(node) || ts.isConstructorDeclaration(node)) {
+            return getVariableDeclarationTypeVisibilityError;
+        }
+        else if (ts.isSetAccessor(node) || ts.isGetAccessor(node)) {
+            return getAccessorDeclarationTypeVisibilityError;
+        }
+        else if (ts.isConstructSignatureDeclaration(node) || ts.isCallSignatureDeclaration(node) || ts.isMethodDeclaration(node) || ts.isMethodSignature(node) || ts.isFunctionDeclaration(node) || ts.isIndexSignatureDeclaration(node)) {
+            return getReturnTypeVisibilityError;
+        }
+        else if (ts.isParameter(node)) {
+            if (ts.isParameterPropertyDeclaration(node) && ts.hasModifier(node.parent, 8 /* Private */)) {
+                return getVariableDeclarationTypeVisibilityError;
+            }
+            return getParameterDeclarationTypeVisibilityError;
+        }
+        else if (ts.isTypeParameterDeclaration(node)) {
+            return getTypeParameterConstraintVisibilityError;
+        }
+        else if (ts.isExpressionWithTypeArguments(node)) {
+            return getHeritageClauseVisibilityError;
+        }
+        else if (ts.isImportEqualsDeclaration(node)) {
+            return getImportEntityNameVisibilityError;
+        }
+        else if (ts.isTypeAliasDeclaration(node)) {
+            return getTypeAliasDeclarationVisibilityError;
+        }
+        else {
+            return ts.Debug.assertNever(node, "Attempted to set a declaration diagnostic context for unhandled node kind: " + ts.SyntaxKind[node.kind]);
+        }
+        function getVariableDeclarationTypeVisibilityDiagnosticMessage(symbolAccessibilityResult) {
+            if (node.kind === 232 /* VariableDeclaration */ || node.kind === 182 /* BindingElement */) {
+                return symbolAccessibilityResult.errorModuleName ?
+                    symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                        ts.Diagnostics.Exported_variable_0_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :
+                        ts.Diagnostics.Exported_variable_0_has_or_is_using_name_1_from_private_module_2 :
+                    ts.Diagnostics.Exported_variable_0_has_or_is_using_private_name_1;
+            }
+            // This check is to ensure we don't report error on constructor parameter property as that error would be reported during parameter emit
+            // The only exception here is if the constructor was marked as private. we are not emitting the constructor parameters at all.
+            else if (node.kind === 152 /* PropertyDeclaration */ || node.kind === 151 /* PropertySignature */ ||
+                (node.kind === 149 /* Parameter */ && ts.hasModifier(node.parent, 8 /* Private */))) {
+                // TODO(jfreeman): Deal with computed properties in error reporting.
+                if (ts.hasModifier(node, 32 /* Static */)) {
+                    return symbolAccessibilityResult.errorModuleName ?
+                        symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                            ts.Diagnostics.Public_static_property_0_of_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :
+                            ts.Diagnostics.Public_static_property_0_of_exported_class_has_or_is_using_name_1_from_private_module_2 :
+                        ts.Diagnostics.Public_static_property_0_of_exported_class_has_or_is_using_private_name_1;
+                }
+                else if (node.parent.kind === 235 /* ClassDeclaration */ || node.kind === 149 /* Parameter */) {
+                    return symbolAccessibilityResult.errorModuleName ?
+                        symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                            ts.Diagnostics.Public_property_0_of_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :
+                            ts.Diagnostics.Public_property_0_of_exported_class_has_or_is_using_name_1_from_private_module_2 :
+                        ts.Diagnostics.Public_property_0_of_exported_class_has_or_is_using_private_name_1;
+                }
+                else {
+                    // Interfaces cannot have types that cannot be named
+                    return symbolAccessibilityResult.errorModuleName ?
+                        ts.Diagnostics.Property_0_of_exported_interface_has_or_is_using_name_1_from_private_module_2 :
+                        ts.Diagnostics.Property_0_of_exported_interface_has_or_is_using_private_name_1;
+                }
+            }
+        }
+        function getVariableDeclarationTypeVisibilityError(symbolAccessibilityResult) {
+            var diagnosticMessage = getVariableDeclarationTypeVisibilityDiagnosticMessage(symbolAccessibilityResult);
+            return diagnosticMessage !== undefined ? {
+                diagnosticMessage: diagnosticMessage,
+                errorNode: node,
+                typeName: node.name
+            } : undefined;
+        }
+        function getAccessorDeclarationTypeVisibilityError(symbolAccessibilityResult) {
+            var diagnosticMessage;
+            if (node.kind === 157 /* SetAccessor */) {
+                // Getters can infer the return type from the returned expression, but setters cannot, so the
+                // "_from_external_module_1_but_cannot_be_named" case cannot occur.
+                if (ts.hasModifier(node, 32 /* Static */)) {
+                    diagnosticMessage = symbolAccessibilityResult.errorModuleName ?
+                        ts.Diagnostics.Parameter_type_of_public_static_setter_0_from_exported_class_has_or_is_using_name_1_from_private_module_2 :
+                        ts.Diagnostics.Parameter_type_of_public_static_setter_0_from_exported_class_has_or_is_using_private_name_1;
+                }
+                else {
+                    diagnosticMessage = symbolAccessibilityResult.errorModuleName ?
+                        ts.Diagnostics.Parameter_type_of_public_setter_0_from_exported_class_has_or_is_using_name_1_from_private_module_2 :
+                        ts.Diagnostics.Parameter_type_of_public_setter_0_from_exported_class_has_or_is_using_private_name_1;
+                }
+            }
+            else {
+                if (ts.hasModifier(node, 32 /* Static */)) {
+                    diagnosticMessage = symbolAccessibilityResult.errorModuleName ?
+                        symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                            ts.Diagnostics.Return_type_of_public_static_getter_0_from_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :
+                            ts.Diagnostics.Return_type_of_public_static_getter_0_from_exported_class_has_or_is_using_name_1_from_private_module_2 :
+                        ts.Diagnostics.Return_type_of_public_static_getter_0_from_exported_class_has_or_is_using_private_name_1;
+                }
+                else {
+                    diagnosticMessage = symbolAccessibilityResult.errorModuleName ?
+                        symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                            ts.Diagnostics.Return_type_of_public_getter_0_from_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :
+                            ts.Diagnostics.Return_type_of_public_getter_0_from_exported_class_has_or_is_using_name_1_from_private_module_2 :
+                        ts.Diagnostics.Return_type_of_public_getter_0_from_exported_class_has_or_is_using_private_name_1;
+                }
+            }
+            return {
+                diagnosticMessage: diagnosticMessage,
+                errorNode: node.name,
+                typeName: node.name
+            };
+        }
+        function getReturnTypeVisibilityError(symbolAccessibilityResult) {
+            var diagnosticMessage;
+            switch (node.kind) {
+                case 159 /* ConstructSignature */:
+                    // Interfaces cannot have return types that cannot be named
+                    diagnosticMessage = symbolAccessibilityResult.errorModuleName ?
+                        ts.Diagnostics.Return_type_of_constructor_signature_from_exported_interface_has_or_is_using_name_0_from_private_module_1 :
+                        ts.Diagnostics.Return_type_of_constructor_signature_from_exported_interface_has_or_is_using_private_name_0;
+                    break;
+                case 158 /* CallSignature */:
+                    // Interfaces cannot have return types that cannot be named
+                    diagnosticMessage = symbolAccessibilityResult.errorModuleName ?
+                        ts.Diagnostics.Return_type_of_call_signature_from_exported_interface_has_or_is_using_name_0_from_private_module_1 :
+                        ts.Diagnostics.Return_type_of_call_signature_from_exported_interface_has_or_is_using_private_name_0;
+                    break;
+                case 160 /* IndexSignature */:
+                    // Interfaces cannot have return types that cannot be named
+                    diagnosticMessage = symbolAccessibilityResult.errorModuleName ?
+                        ts.Diagnostics.Return_type_of_index_signature_from_exported_interface_has_or_is_using_name_0_from_private_module_1 :
+                        ts.Diagnostics.Return_type_of_index_signature_from_exported_interface_has_or_is_using_private_name_0;
+                    break;
+                case 154 /* MethodDeclaration */:
+                case 153 /* MethodSignature */:
+                    if (ts.hasModifier(node, 32 /* Static */)) {
+                        diagnosticMessage = symbolAccessibilityResult.errorModuleName ?
+                            symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                                ts.Diagnostics.Return_type_of_public_static_method_from_exported_class_has_or_is_using_name_0_from_external_module_1_but_cannot_be_named :
+                                ts.Diagnostics.Return_type_of_public_static_method_from_exported_class_has_or_is_using_name_0_from_private_module_1 :
+                            ts.Diagnostics.Return_type_of_public_static_method_from_exported_class_has_or_is_using_private_name_0;
+                    }
+                    else if (node.parent.kind === 235 /* ClassDeclaration */) {
+                        diagnosticMessage = symbolAccessibilityResult.errorModuleName ?
+                            symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                                ts.Diagnostics.Return_type_of_public_method_from_exported_class_has_or_is_using_name_0_from_external_module_1_but_cannot_be_named :
+                                ts.Diagnostics.Return_type_of_public_method_from_exported_class_has_or_is_using_name_0_from_private_module_1 :
+                            ts.Diagnostics.Return_type_of_public_method_from_exported_class_has_or_is_using_private_name_0;
+                    }
+                    else {
+                        // Interfaces cannot have return types that cannot be named
+                        diagnosticMessage = symbolAccessibilityResult.errorModuleName ?
+                            ts.Diagnostics.Return_type_of_method_from_exported_interface_has_or_is_using_name_0_from_private_module_1 :
+                            ts.Diagnostics.Return_type_of_method_from_exported_interface_has_or_is_using_private_name_0;
+                    }
+                    break;
+                case 234 /* FunctionDeclaration */:
+                    diagnosticMessage = symbolAccessibilityResult.errorModuleName ?
+                        symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                            ts.Diagnostics.Return_type_of_exported_function_has_or_is_using_name_0_from_external_module_1_but_cannot_be_named :
+                            ts.Diagnostics.Return_type_of_exported_function_has_or_is_using_name_0_from_private_module_1 :
+                        ts.Diagnostics.Return_type_of_exported_function_has_or_is_using_private_name_0;
+                    break;
+                default:
+                    return ts.Debug.fail("This is unknown kind for signature: " + node.kind);
+            }
+            return {
+                diagnosticMessage: diagnosticMessage,
+                errorNode: node.name || node
+            };
+        }
+        function getParameterDeclarationTypeVisibilityError(symbolAccessibilityResult) {
+            var diagnosticMessage = getParameterDeclarationTypeVisibilityDiagnosticMessage(symbolAccessibilityResult);
+            return diagnosticMessage !== undefined ? {
+                diagnosticMessage: diagnosticMessage,
+                errorNode: node,
+                typeName: node.name
+            } : undefined;
+        }
+        function getParameterDeclarationTypeVisibilityDiagnosticMessage(symbolAccessibilityResult) {
+            switch (node.parent.kind) {
+                case 155 /* Constructor */:
+                    return symbolAccessibilityResult.errorModuleName ?
+                        symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                            ts.Diagnostics.Parameter_0_of_constructor_from_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :
+                            ts.Diagnostics.Parameter_0_of_constructor_from_exported_class_has_or_is_using_name_1_from_private_module_2 :
+                        ts.Diagnostics.Parameter_0_of_constructor_from_exported_class_has_or_is_using_private_name_1;
+                case 159 /* ConstructSignature */:
+                case 164 /* ConstructorType */:
+                    // Interfaces cannot have parameter types that cannot be named
+                    return symbolAccessibilityResult.errorModuleName ?
+                        ts.Diagnostics.Parameter_0_of_constructor_signature_from_exported_interface_has_or_is_using_name_1_from_private_module_2 :
+                        ts.Diagnostics.Parameter_0_of_constructor_signature_from_exported_interface_has_or_is_using_private_name_1;
+                case 158 /* CallSignature */:
+                    // Interfaces cannot have parameter types that cannot be named
+                    return symbolAccessibilityResult.errorModuleName ?
+                        ts.Diagnostics.Parameter_0_of_call_signature_from_exported_interface_has_or_is_using_name_1_from_private_module_2 :
+                        ts.Diagnostics.Parameter_0_of_call_signature_from_exported_interface_has_or_is_using_private_name_1;
+                case 160 /* IndexSignature */:
+                    // Interfaces cannot have parameter types that cannot be named
+                    return symbolAccessibilityResult.errorModuleName ?
+                        ts.Diagnostics.Parameter_0_of_index_signature_from_exported_interface_has_or_is_using_name_1_from_private_module_2 :
+                        ts.Diagnostics.Parameter_0_of_index_signature_from_exported_interface_has_or_is_using_private_name_1;
+                case 154 /* MethodDeclaration */:
+                case 153 /* MethodSignature */:
+                    if (ts.hasModifier(node.parent, 32 /* Static */)) {
+                        return symbolAccessibilityResult.errorModuleName ?
+                            symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                                ts.Diagnostics.Parameter_0_of_public_static_method_from_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :
+                                ts.Diagnostics.Parameter_0_of_public_static_method_from_exported_class_has_or_is_using_name_1_from_private_module_2 :
+                            ts.Diagnostics.Parameter_0_of_public_static_method_from_exported_class_has_or_is_using_private_name_1;
+                    }
+                    else if (node.parent.parent.kind === 235 /* ClassDeclaration */) {
+                        return symbolAccessibilityResult.errorModuleName ?
+                            symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                                ts.Diagnostics.Parameter_0_of_public_method_from_exported_class_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :
+                                ts.Diagnostics.Parameter_0_of_public_method_from_exported_class_has_or_is_using_name_1_from_private_module_2 :
+                            ts.Diagnostics.Parameter_0_of_public_method_from_exported_class_has_or_is_using_private_name_1;
+                    }
+                    else {
+                        // Interfaces cannot have parameter types that cannot be named
+                        return symbolAccessibilityResult.errorModuleName ?
+                            ts.Diagnostics.Parameter_0_of_method_from_exported_interface_has_or_is_using_name_1_from_private_module_2 :
+                            ts.Diagnostics.Parameter_0_of_method_from_exported_interface_has_or_is_using_private_name_1;
+                    }
+                case 234 /* FunctionDeclaration */:
+                case 163 /* FunctionType */:
+                    return symbolAccessibilityResult.errorModuleName ?
+                        symbolAccessibilityResult.accessibility === 2 /* CannotBeNamed */ ?
+                            ts.Diagnostics.Parameter_0_of_exported_function_has_or_is_using_name_1_from_external_module_2_but_cannot_be_named :
+                            ts.Diagnostics.Parameter_0_of_exported_function_has_or_is_using_name_1_from_private_module_2 :
+                        ts.Diagnostics.Parameter_0_of_exported_function_has_or_is_using_private_name_1;
+                default:
+                    return ts.Debug.fail("Unknown parent for parameter: " + ts.SyntaxKind[node.parent.kind]);
+            }
+        }
+        function getTypeParameterConstraintVisibilityError() {
+            // Type parameter constraints are named by user so we should always be able to name it
+            var diagnosticMessage;
+            switch (node.parent.kind) {
+                case 235 /* ClassDeclaration */:
+                    diagnosticMessage = ts.Diagnostics.Type_parameter_0_of_exported_class_has_or_is_using_private_name_1;
+                    break;
+                case 236 /* InterfaceDeclaration */:
+                    diagnosticMessage = ts.Diagnostics.Type_parameter_0_of_exported_interface_has_or_is_using_private_name_1;
+                    break;
+                case 159 /* ConstructSignature */:
+                    diagnosticMessage = ts.Diagnostics.Type_parameter_0_of_constructor_signature_from_exported_interface_has_or_is_using_private_name_1;
+                    break;
+                case 158 /* CallSignature */:
+                    diagnosticMessage = ts.Diagnostics.Type_parameter_0_of_call_signature_from_exported_interface_has_or_is_using_private_name_1;
+                    break;
+                case 154 /* MethodDeclaration */:
+                case 153 /* MethodSignature */:
+                    if (ts.hasModifier(node.parent, 32 /* Static */)) {
+                        diagnosticMessage = ts.Diagnostics.Type_parameter_0_of_public_static_method_from_exported_class_has_or_is_using_private_name_1;
+                    }
+                    else if (node.parent.parent.kind === 235 /* ClassDeclaration */) {
+                        diagnosticMessage = ts.Diagnostics.Type_parameter_0_of_public_method_from_exported_class_has_or_is_using_private_name_1;
+                    }
+                    else {
+                        diagnosticMessage = ts.Diagnostics.Type_parameter_0_of_method_from_exported_interface_has_or_is_using_private_name_1;
+                    }
+                    break;
+                case 234 /* FunctionDeclaration */:
+                    diagnosticMessage = ts.Diagnostics.Type_parameter_0_of_exported_function_has_or_is_using_private_name_1;
+                    break;
+                case 237 /* TypeAliasDeclaration */:
+                    diagnosticMessage = ts.Diagnostics.Type_parameter_0_of_exported_type_alias_has_or_is_using_private_name_1;
+                    break;
+                default:
+                    return ts.Debug.fail("This is unknown parent for type parameter: " + node.parent.kind);
+            }
+            return {
+                diagnosticMessage: diagnosticMessage,
+                errorNode: node,
+                typeName: node.name
+            };
+        }
+        function getHeritageClauseVisibilityError() {
+            var diagnosticMessage;
+            // Heritage clause is written by user so it can always be named
+            if (node.parent.parent.kind === 235 /* ClassDeclaration */) {
+                // Class or Interface implemented/extended is inaccessible
+                diagnosticMessage = node.parent.token === 108 /* ImplementsKeyword */ ?
+                    ts.Diagnostics.Implements_clause_of_exported_class_0_has_or_is_using_private_name_1 :
+                    ts.Diagnostics.extends_clause_of_exported_class_0_has_or_is_using_private_name_1;
+            }
+            else {
+                // interface is inaccessible
+                diagnosticMessage = ts.Diagnostics.extends_clause_of_exported_interface_0_has_or_is_using_private_name_1;
+            }
+            return {
+                diagnosticMessage: diagnosticMessage,
+                errorNode: node,
+                typeName: ts.getNameOfDeclaration(node.parent.parent)
+            };
+        }
+        function getImportEntityNameVisibilityError() {
+            return {
+                diagnosticMessage: ts.Diagnostics.Import_declaration_0_is_using_private_name_1,
+                errorNode: node,
+                typeName: node.name
+            };
+        }
+        function getTypeAliasDeclarationVisibilityError() {
+            return {
+                diagnosticMessage: ts.Diagnostics.Exported_type_alias_0_has_or_is_using_private_name_1,
+                errorNode: node.type,
+                typeName: node.name
+            };
+        }
+    }
+    ts.createGetSymbolAccessibilityDiagnosticForNode = createGetSymbolAccessibilityDiagnosticForNode;
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    function getDeclarationDiagnostics(host, resolver, file) {
+        if (file && ts.isSourceFileJavaScript(file)) {
+            return []; // No declaration diagnostics for js for now
+        }
+        var compilerOptions = host.getCompilerOptions();
+        var result = ts.transformNodes(resolver, host, compilerOptions, file ? [file] : ts.filter(host.getSourceFiles(), ts.isSourceFileNotJavaScript), [transformDeclarations], /*allowDtsFiles*/ false);
+        return result.diagnostics;
+    }
+    ts.getDeclarationDiagnostics = getDeclarationDiagnostics;
+    var declarationEmitNodeBuilderFlags = 1024 /* MultilineObjectLiterals */ |
+        2048 /* WriteClassExpressionAsTypeLiteral */ |
+        4096 /* UseTypeOfFunction */ |
+        8 /* UseStructuralFallback */ |
+        524288 /* AllowEmptyTuple */ |
+        4 /* GenerateNamesForShadowedTypeParams */;
+    /**
+     * Transforms a ts file into a .d.ts file
+     * This process requires type information, which is retrieved through the emit resolver. Because of this,
+     * in many places this transformer assumes it will be operating on parse tree nodes directly.
+     * This means that _no transforms should be allowed to occur before this one_.
+     */
+    function transformDeclarations(context) {
+        var throwDiagnostic = function () { return ts.Debug.fail("Diagnostic emitted without context"); };
+        var getSymbolAccessibilityDiagnostic = throwDiagnostic;
+        var needsDeclare = true;
+        var isBundledEmit = false;
+        var resultHasExternalModuleIndicator = false;
+        var needsScopeFixMarker = false;
+        var resultHasScopeMarker = false;
+        var enclosingDeclaration;
+        var necessaryTypeRefernces;
+        var lateMarkedStatements;
+        var lateStatementReplacementMap;
+        var suppressNewDiagnosticContexts;
+        var host = context.getEmitHost();
+        var symbolTracker = {
+            trackSymbol: trackSymbol,
+            reportInaccessibleThisError: reportInaccessibleThisError,
+            reportInaccessibleUniqueSymbolError: reportInaccessibleUniqueSymbolError,
+            reportPrivateInBaseOfClassExpression: reportPrivateInBaseOfClassExpression,
+            moduleResolverHost: host,
+            trackReferencedAmbientModule: trackReferencedAmbientModule,
+        };
+        var errorNameNode;
+        var currentSourceFile;
+        var refs;
+        var resolver = context.getEmitResolver();
+        var options = context.getCompilerOptions();
+        var newLine = ts.getNewLineCharacter(options);
+        var noResolve = options.noResolve, stripInternal = options.stripInternal;
+        return transformRoot;
+        function recordTypeReferenceDirectivesIfNecessary(typeReferenceDirectives) {
+            if (!typeReferenceDirectives) {
+                return;
+            }
+            necessaryTypeRefernces = necessaryTypeRefernces || ts.createMap();
+            for (var _i = 0, typeReferenceDirectives_2 = typeReferenceDirectives; _i < typeReferenceDirectives_2.length; _i++) {
+                var ref = typeReferenceDirectives_2[_i];
+                necessaryTypeRefernces.set(ref, true);
+            }
+        }
+        function trackReferencedAmbientModule(node) {
+            var container = ts.getSourceFileOfNode(node);
+            refs.set("" + ts.getOriginalNodeId(container), container);
+        }
+        function handleSymbolAccessibilityError(symbolAccessibilityResult) {
+            if (symbolAccessibilityResult.accessibility === 0 /* Accessible */) {
+                // Add aliases back onto the possible imports list if they're not there so we can try them again with updated visibility info
+                if (symbolAccessibilityResult && symbolAccessibilityResult.aliasesToMakeVisible) {
+                    if (!lateMarkedStatements) {
+                        lateMarkedStatements = symbolAccessibilityResult.aliasesToMakeVisible;
+                    }
+                    else {
+                        for (var _i = 0, _a = symbolAccessibilityResult.aliasesToMakeVisible; _i < _a.length; _i++) {
+                            var ref = _a[_i];
+                            ts.pushIfUnique(lateMarkedStatements, ref);
+                        }
+                    }
+                }
+                // TODO: Do all these accessibility checks inside/after the first pass in the checker when declarations are enabled, if possible
+            }
+            else {
+                // Report error
+                var errorInfo = getSymbolAccessibilityDiagnostic(symbolAccessibilityResult);
+                if (errorInfo) {
+                    if (errorInfo.typeName) {
+                        context.addDiagnostic(ts.createDiagnosticForNode(symbolAccessibilityResult.errorNode || errorInfo.errorNode, errorInfo.diagnosticMessage, ts.getTextOfNode(errorInfo.typeName), symbolAccessibilityResult.errorSymbolName, symbolAccessibilityResult.errorModuleName));
+                    }
+                    else {
+                        context.addDiagnostic(ts.createDiagnosticForNode(symbolAccessibilityResult.errorNode || errorInfo.errorNode, errorInfo.diagnosticMessage, symbolAccessibilityResult.errorSymbolName, symbolAccessibilityResult.errorModuleName));
+                    }
+                }
+            }
+        }
+        function trackSymbol(symbol, enclosingDeclaration, meaning) {
+            if (symbol.flags & 262144 /* TypeParameter */)
+                return;
+            handleSymbolAccessibilityError(resolver.isSymbolAccessible(symbol, enclosingDeclaration, meaning, /*shouldComputeAliasesToMakeVisible*/ true));
+            recordTypeReferenceDirectivesIfNecessary(resolver.getTypeReferenceDirectivesForSymbol(symbol, meaning));
+        }
+        function reportPrivateInBaseOfClassExpression(propertyName) {
+            if (errorNameNode) {
+                context.addDiagnostic(ts.createDiagnosticForNode(errorNameNode, ts.Diagnostics.Property_0_of_exported_class_expression_may_not_be_private_or_protected, propertyName));
+            }
+        }
+        function reportInaccessibleUniqueSymbolError() {
+            if (errorNameNode) {
+                context.addDiagnostic(ts.createDiagnosticForNode(errorNameNode, ts.Diagnostics.The_inferred_type_of_0_references_an_inaccessible_1_type_A_type_annotation_is_necessary, ts.declarationNameToString(errorNameNode), "unique symbol"));
+            }
+        }
+        function reportInaccessibleThisError() {
+            if (errorNameNode) {
+                context.addDiagnostic(ts.createDiagnosticForNode(errorNameNode, ts.Diagnostics.The_inferred_type_of_0_references_an_inaccessible_1_type_A_type_annotation_is_necessary, ts.declarationNameToString(errorNameNode), "this"));
+            }
+        }
+        function transformRoot(node) {
+            if (node.kind === 274 /* SourceFile */ && (node.isDeclarationFile || ts.isSourceFileJavaScript(node))) {
+                return node;
+            }
+            if (node.kind === 275 /* Bundle */) {
+                isBundledEmit = true;
+                var refs_1 = ts.createMap();
+                var hasNoDefaultLib_1 = false;
+                var bundle = ts.createBundle(ts.map(node.sourceFiles, function (sourceFile) {
+                    if (sourceFile.isDeclarationFile || ts.isSourceFileJavaScript(sourceFile))
+                        return undefined; // Omit declaration files from bundle results, too // TODO: GH#18217
+                    hasNoDefaultLib_1 = hasNoDefaultLib_1 || sourceFile.hasNoDefaultLib;
+                    currentSourceFile = sourceFile;
+                    enclosingDeclaration = sourceFile;
+                    lateMarkedStatements = undefined;
+                    suppressNewDiagnosticContexts = false;
+                    lateStatementReplacementMap = ts.createMap();
+                    getSymbolAccessibilityDiagnostic = throwDiagnostic;
+                    needsScopeFixMarker = false;
+                    resultHasScopeMarker = false;
+                    collectReferences(sourceFile, refs_1);
+                    if (ts.isExternalModule(sourceFile)) {
+                        resultHasExternalModuleIndicator = false; // unused in external module bundle emit (all external modules are within module blocks, therefore are known to be modules)
+                        needsDeclare = false;
+                        var statements_5 = ts.visitNodes(sourceFile.statements, visitDeclarationStatements);
+                        var newFile = ts.updateSourceFileNode(sourceFile, [ts.createModuleDeclaration([], [ts.createModifier(124 /* DeclareKeyword */)], ts.createLiteral(ts.getResolvedExternalModuleName(context.getEmitHost(), sourceFile)), ts.createModuleBlock(ts.setTextRange(ts.createNodeArray(transformAndReplaceLatePaintedStatements(statements_5)), sourceFile.statements)))], /*isDeclarationFile*/ true, /*referencedFiles*/ [], /*typeReferences*/ [], /*hasNoDefaultLib*/ false, /*libReferences*/ []);
+                        return newFile;
+                    }
+                    needsDeclare = true;
+                    var updated = ts.visitNodes(sourceFile.statements, visitDeclarationStatements);
+                    return ts.updateSourceFileNode(sourceFile, transformAndReplaceLatePaintedStatements(updated), /*isDeclarationFile*/ true, /*referencedFiles*/ [], /*typeReferences*/ [], /*hasNoDefaultLib*/ false, /*libReferences*/ []);
+                }), ts.mapDefined(node.prepends, function (prepend) {
+                    if (prepend.kind === 277 /* InputFiles */) {
+                        return ts.createUnparsedSourceFile(prepend.declarationText, prepend.declarationMapText);
+                    }
+                }));
+                bundle.syntheticFileReferences = [];
+                bundle.syntheticTypeReferences = getFileReferencesForUsedTypeReferences();
+                bundle.hasNoDefaultLib = hasNoDefaultLib_1;
+                var outputFilePath_1 = ts.getDirectoryPath(ts.normalizeSlashes(ts.getOutputPathsFor(node, host, /*forceDtsPaths*/ true).declarationFilePath));
+                var referenceVisitor_1 = mapReferencesIntoArray(bundle.syntheticFileReferences, outputFilePath_1);
+                refs_1.forEach(referenceVisitor_1);
+                return bundle;
+            }
+            // Single source file
+            needsDeclare = true;
+            needsScopeFixMarker = false;
+            resultHasScopeMarker = false;
+            enclosingDeclaration = node;
+            currentSourceFile = node;
+            getSymbolAccessibilityDiagnostic = throwDiagnostic;
+            isBundledEmit = false;
+            resultHasExternalModuleIndicator = false;
+            suppressNewDiagnosticContexts = false;
+            lateMarkedStatements = undefined;
+            lateStatementReplacementMap = ts.createMap();
+            necessaryTypeRefernces = undefined;
+            refs = collectReferences(currentSourceFile, ts.createMap());
+            var references = [];
+            var outputFilePath = ts.getDirectoryPath(ts.normalizeSlashes(ts.getOutputPathsFor(node, host, /*forceDtsPaths*/ true).declarationFilePath));
+            var referenceVisitor = mapReferencesIntoArray(references, outputFilePath);
+            var statements = ts.visitNodes(node.statements, visitDeclarationStatements);
+            var combinedStatements = ts.setTextRange(ts.createNodeArray(transformAndReplaceLatePaintedStatements(statements)), node.statements);
+            refs.forEach(referenceVisitor);
+            var emittedImports = ts.filter(combinedStatements, ts.isAnyImportSyntax);
+            if (ts.isExternalModule(node) && (!resultHasExternalModuleIndicator || (needsScopeFixMarker && !resultHasScopeMarker))) {
+                combinedStatements = ts.setTextRange(ts.createNodeArray(combinedStatements.concat([ts.createExportDeclaration(/*decorators*/ undefined, /*modifiers*/ undefined, ts.createNamedExports([]), /*moduleSpecifier*/ undefined)])), combinedStatements);
+            }
+            var updated = ts.updateSourceFileNode(node, combinedStatements, /*isDeclarationFile*/ true, references, getFileReferencesForUsedTypeReferences(), node.hasNoDefaultLib);
+            return updated;
+            function getFileReferencesForUsedTypeReferences() {
+                return necessaryTypeRefernces ? ts.mapDefined(ts.arrayFrom(necessaryTypeRefernces.keys()), getFileReferenceForTypeName) : [];
+            }
+            function getFileReferenceForTypeName(typeName) {
+                // Elide type references for which we have imports
+                if (emittedImports) {
+                    for (var _i = 0, emittedImports_1 = emittedImports; _i < emittedImports_1.length; _i++) {
+                        var importStatement = emittedImports_1[_i];
+                        if (ts.isImportEqualsDeclaration(importStatement) && ts.isExternalModuleReference(importStatement.moduleReference)) {
+                            var expr = importStatement.moduleReference.expression;
+                            if (ts.isStringLiteralLike(expr) && expr.text === typeName) {
+                                return undefined;
+                            }
+                        }
+                        else if (ts.isImportDeclaration(importStatement) && ts.isStringLiteral(importStatement.moduleSpecifier) && importStatement.moduleSpecifier.text === typeName) {
+                            return undefined;
+                        }
+                    }
+                }
+                return { fileName: typeName, pos: -1, end: -1 };
+            }
+            function mapReferencesIntoArray(references, outputFilePath) {
+                return function (file) {
+                    var declFileName;
+                    if (file.isDeclarationFile) { // Neither decl files or js should have their refs changed
+                        declFileName = file.fileName;
+                    }
+                    else {
+                        if (isBundledEmit && ts.contains(node.sourceFiles, file))
+                            return; // Omit references to files which are being merged
+                        var paths = ts.getOutputPathsFor(file, host, /*forceDtsPaths*/ true);
+                        declFileName = paths.declarationFilePath || paths.jsFilePath;
+                    }
+                    if (declFileName) {
+                        var fileName = ts.getRelativePathToDirectoryOrUrl(outputFilePath, declFileName, host.getCurrentDirectory(), host.getCanonicalFileName, 
+                        /*isAbsolutePathAnUrl*/ false);
+                        if (ts.startsWith(fileName, "./") && ts.hasExtension(fileName)) {
+                            fileName = fileName.substring(2);
+                        }
+                        references.push({ pos: -1, end: -1, fileName: fileName });
+                    }
+                };
+            }
+        }
+        function collectReferences(sourceFile, ret) {
+            if (noResolve || ts.isSourceFileJavaScript(sourceFile))
+                return ret;
+            ts.forEach(sourceFile.referencedFiles, function (f) {
+                var elem = ts.tryResolveScriptReference(host, sourceFile, f);
+                if (elem) {
+                    ret.set("" + ts.getOriginalNodeId(elem), elem);
+                }
+            });
+            return ret;
+        }
+        function filterBindingPatternInitializers(name) {
+            if (name.kind === 71 /* Identifier */) {
+                return name;
+            }
+            else {
+                if (name.kind === 181 /* ArrayBindingPattern */) {
+                    return ts.updateArrayBindingPattern(name, ts.visitNodes(name.elements, visitBindingElement));
+                }
+                else {
+                    return ts.updateObjectBindingPattern(name, ts.visitNodes(name.elements, visitBindingElement));
+                }
+            }
+            function visitBindingElement(elem) {
+                if (elem.kind === 206 /* OmittedExpression */) {
+                    return elem;
+                }
+                return ts.updateBindingElement(elem, elem.dotDotDotToken, elem.propertyName, filterBindingPatternInitializers(elem.name), shouldPrintWithInitializer(elem) ? elem.initializer : undefined);
+            }
+        }
+        function ensureParameter(p, modifierMask) {
+            var oldDiag;
+            if (!suppressNewDiagnosticContexts) {
+                oldDiag = getSymbolAccessibilityDiagnostic;
+                getSymbolAccessibilityDiagnostic = ts.createGetSymbolAccessibilityDiagnosticForNode(p);
+            }
+            var newParam = ts.updateParameter(p, 
+            /*decorators*/ undefined, maskModifiers(p, modifierMask), p.dotDotDotToken, filterBindingPatternInitializers(p.name), resolver.isOptionalParameter(p) ? (p.questionToken || ts.createToken(55 /* QuestionToken */)) : undefined, ensureType(p, p.type, /*ignorePrivate*/ true), // Ignore private param props, since this type is going straight back into a param
+            ensureNoInitializer(p));
+            if (!suppressNewDiagnosticContexts) {
+                getSymbolAccessibilityDiagnostic = oldDiag;
+            }
+            return newParam;
+        }
+        function shouldPrintWithInitializer(node) {
+            return canHaveLiteralInitializer(node) && resolver.isLiteralConstDeclaration(ts.getParseTreeNode(node)); // TODO: Make safe
+        }
+        function ensureNoInitializer(node) {
+            if (shouldPrintWithInitializer(node)) {
+                return resolver.createLiteralConstValue(ts.getParseTreeNode(node)); // TODO: Make safe
+            }
+            return undefined;
+        }
+        function ensureType(node, type, ignorePrivate) {
+            if (!ignorePrivate && ts.hasModifier(node, 8 /* Private */)) {
+                // Private nodes emit no types (except private parameter properties, whose parameter types are actually visible)
+                return;
+            }
+            if (shouldPrintWithInitializer(node)) {
+                // Literal const declarations will have an initializer ensured rather than a type
+                return;
+            }
+            var shouldUseResolverType = node.kind === 149 /* Parameter */ &&
+                (resolver.isRequiredInitializedParameter(node) ||
+                    resolver.isOptionalUninitializedParameterProperty(node));
+            if (type && !shouldUseResolverType) {
+                return ts.visitNode(type, visitDeclarationSubtree);
+            }
+            if (!ts.getParseTreeNode(node)) {
+                return type ? ts.visitNode(type, visitDeclarationSubtree) : ts.createKeywordTypeNode(119 /* AnyKeyword */);
+            }
+            if (node.kind === 157 /* SetAccessor */) {
+                // Set accessors with no associated type node (from it's param or get accessor return) are `any` since they are never contextually typed right now
+                // (The inferred type here will be void, but the old declaration emitter printed `any`, so this replicates that)
+                return ts.createKeywordTypeNode(119 /* AnyKeyword */);
+            }
+            errorNameNode = node.name;
+            var oldDiag;
+            if (!suppressNewDiagnosticContexts) {
+                oldDiag = getSymbolAccessibilityDiagnostic;
+                getSymbolAccessibilityDiagnostic = ts.createGetSymbolAccessibilityDiagnosticForNode(node);
+            }
+            if (node.kind === 232 /* VariableDeclaration */ || node.kind === 182 /* BindingElement */) {
+                return cleanup(resolver.createTypeOfDeclaration(node, enclosingDeclaration, declarationEmitNodeBuilderFlags, symbolTracker));
+            }
+            if (node.kind === 149 /* Parameter */
+                || node.kind === 152 /* PropertyDeclaration */
+                || node.kind === 151 /* PropertySignature */) {
+                if (!node.initializer)
+                    return cleanup(resolver.createTypeOfDeclaration(node, enclosingDeclaration, declarationEmitNodeBuilderFlags, symbolTracker, shouldUseResolverType));
+                return cleanup(resolver.createTypeOfDeclaration(node, enclosingDeclaration, declarationEmitNodeBuilderFlags, symbolTracker, shouldUseResolverType) || resolver.createTypeOfExpression(node.initializer, enclosingDeclaration, declarationEmitNodeBuilderFlags, symbolTracker));
+            }
+            return cleanup(resolver.createReturnTypeOfSignatureDeclaration(node, enclosingDeclaration, declarationEmitNodeBuilderFlags, symbolTracker));
+            function cleanup(returnValue) {
+                errorNameNode = undefined;
+                if (!suppressNewDiagnosticContexts) {
+                    getSymbolAccessibilityDiagnostic = oldDiag;
+                }
+                return returnValue || ts.createKeywordTypeNode(119 /* AnyKeyword */);
+            }
+        }
+        function isDeclarationAndNotVisible(node) {
+            node = ts.getParseTreeNode(node);
+            switch (node.kind) {
+                case 234 /* FunctionDeclaration */:
+                case 239 /* ModuleDeclaration */:
+                case 236 /* InterfaceDeclaration */:
+                case 235 /* ClassDeclaration */:
+                case 237 /* TypeAliasDeclaration */:
+                case 238 /* EnumDeclaration */:
+                    return !resolver.isDeclarationVisible(node);
+                // The following should be doing their own visibility checks based on filtering their members
+                case 232 /* VariableDeclaration */:
+                    return !getBindingNameVisible(node);
+                case 243 /* ImportEqualsDeclaration */:
+                case 244 /* ImportDeclaration */:
+                case 250 /* ExportDeclaration */:
+                case 249 /* ExportAssignment */:
+                    return false;
+            }
+            return false;
+        }
+        function getBindingNameVisible(elem) {
+            if (ts.isOmittedExpression(elem)) {
+                return false;
+            }
+            if (ts.isBindingPattern(elem.name)) {
+                // If any child binding pattern element has been marked visible (usually by collect linked aliases), then this is visible
+                return ts.some(elem.name.elements, getBindingNameVisible);
+            }
+            else {
+                return resolver.isDeclarationVisible(elem);
+            }
+        }
+        function updateParamsList(node, params, modifierMask) {
+            if (ts.hasModifier(node, 8 /* Private */)) {
+                return undefined; // TODO: GH#18217
+            }
+            var newParams = ts.map(params, function (p) { return ensureParameter(p, modifierMask); });
+            if (!newParams) {
+                return undefined; // TODO: GH#18217
+            }
+            return ts.createNodeArray(newParams, params.hasTrailingComma);
+        }
+        function ensureTypeParams(node, params) {
+            return ts.hasModifier(node, 8 /* Private */) ? undefined : ts.visitNodes(params, visitDeclarationSubtree);
+        }
+        function isEnclosingDeclaration(node) {
+            return ts.isSourceFile(node)
+                || ts.isTypeAliasDeclaration(node)
+                || ts.isModuleDeclaration(node)
+                || ts.isClassDeclaration(node)
+                || ts.isInterfaceDeclaration(node)
+                || ts.isFunctionLike(node)
+                || ts.isIndexSignatureDeclaration(node)
+                || ts.isMappedTypeNode(node);
+        }
+        function checkEntityNameVisibility(entityName, enclosingDeclaration) {
+            var visibilityResult = resolver.isEntityNameVisible(entityName, enclosingDeclaration);
+            handleSymbolAccessibilityError(visibilityResult);
+            recordTypeReferenceDirectivesIfNecessary(resolver.getTypeReferenceDirectivesForEntityName(entityName));
+        }
+        function preserveJsDoc(updated, original) {
+            if (ts.hasJSDocNodes(updated) && ts.hasJSDocNodes(original)) {
+                updated.jsDoc = original.jsDoc;
+            }
+            return ts.setCommentRange(updated, ts.getCommentRange(original));
+        }
+        function rewriteModuleSpecifier(parent, input) {
+            if (!input)
+                return undefined; // TODO: GH#18217
+            resultHasExternalModuleIndicator = resultHasExternalModuleIndicator || (parent.kind !== 239 /* ModuleDeclaration */ && parent.kind !== 179 /* ImportType */);
+            if (input.kind === 9 /* StringLiteral */ && isBundledEmit) {
+                var newName = ts.getExternalModuleNameFromDeclaration(context.getEmitHost(), resolver, parent);
+                if (newName) {
+                    return ts.createLiteral(newName);
+                }
+            }
+            return input;
+        }
+        function transformImportEqualsDeclaration(decl) {
+            if (!resolver.isDeclarationVisible(decl))
+                return;
+            if (decl.moduleReference.kind === 254 /* ExternalModuleReference */) {
+                // Rewrite external module names if necessary
+                var specifier = ts.getExternalModuleImportEqualsDeclarationExpression(decl);
+                return ts.updateImportEqualsDeclaration(decl, 
+                /*decorators*/ undefined, decl.modifiers, decl.name, ts.updateExternalModuleReference(decl.moduleReference, rewriteModuleSpecifier(decl, specifier)));
+            }
+            else {
+                var oldDiag = getSymbolAccessibilityDiagnostic;
+                getSymbolAccessibilityDiagnostic = ts.createGetSymbolAccessibilityDiagnosticForNode(decl);
+                checkEntityNameVisibility(decl.moduleReference, enclosingDeclaration);
+                getSymbolAccessibilityDiagnostic = oldDiag;
+                return decl;
+            }
+        }
+        function transformImportDeclaration(decl) {
+            if (!decl.importClause) {
+                // import "mod" - possibly needed for side effects? (global interface patches, module augmentations, etc)
+                return ts.updateImportDeclaration(decl, 
+                /*decorators*/ undefined, decl.modifiers, decl.importClause, rewriteModuleSpecifier(decl, decl.moduleSpecifier));
+            }
+            // The `importClause` visibility corresponds to the default's visibility.
+            var visibleDefaultBinding = decl.importClause && decl.importClause.name && resolver.isDeclarationVisible(decl.importClause) ? decl.importClause.name : undefined;
+            if (!decl.importClause.namedBindings) {
+                // No named bindings (either namespace or list), meaning the import is just default or should be elided
+                return visibleDefaultBinding && ts.updateImportDeclaration(decl, /*decorators*/ undefined, decl.modifiers, ts.updateImportClause(decl.importClause, visibleDefaultBinding, 
+                /*namedBindings*/ undefined), rewriteModuleSpecifier(decl, decl.moduleSpecifier));
+            }
+            if (decl.importClause.namedBindings.kind === 246 /* NamespaceImport */) {
+                // Namespace import (optionally with visible default)
+                var namedBindings = resolver.isDeclarationVisible(decl.importClause.namedBindings) ? decl.importClause.namedBindings : /*namedBindings*/ undefined;
+                return visibleDefaultBinding || namedBindings ? ts.updateImportDeclaration(decl, /*decorators*/ undefined, decl.modifiers, ts.updateImportClause(decl.importClause, visibleDefaultBinding, namedBindings), rewriteModuleSpecifier(decl, decl.moduleSpecifier)) : undefined;
+            }
+            // Named imports (optionally with visible default)
+            var bindingList = ts.mapDefined(decl.importClause.namedBindings.elements, function (b) { return resolver.isDeclarationVisible(b) ? b : undefined; });
+            if ((bindingList && bindingList.length) || visibleDefaultBinding) {
+                return ts.updateImportDeclaration(decl, 
+                /*decorators*/ undefined, decl.modifiers, ts.updateImportClause(decl.importClause, visibleDefaultBinding, bindingList && bindingList.length ? ts.updateNamedImports(decl.importClause.namedBindings, bindingList) : undefined), rewriteModuleSpecifier(decl, decl.moduleSpecifier));
+            }
+            // Nothing visible
+        }
+        function transformAndReplaceLatePaintedStatements(statements) {
+            // This is a `while` loop because `handleSymbolAccessibilityError` can see additional import aliases marked as visible during
+            // error handling which must now be included in the output and themselves checked for errors.
+            // For example:
+            // ```
+            // module A {
+            //   export module Q {}
+            //   import B = Q;
+            //   import C = B;
+            //   export import D = C;
+            // }
+            // ```
+            // In such a scenario, only Q and D are initially visible, but we don't consider imports as private names - instead we say they if they are referenced they must
+            // be recorded. So while checking D's visibility we mark C as visible, then we must check C which in turn marks B, completing the chain of
+            // dependent imports and allowing a valid declaration file output. Today, this dependent alias marking only happens for internal import aliases.
+            while (ts.length(lateMarkedStatements)) {
+                var i = lateMarkedStatements.shift();
+                if (!ts.isLateVisibilityPaintedStatement(i)) {
+                    return ts.Debug.fail("Late replaced statement was found which is not handled by the declaration transformer!: " + (ts.SyntaxKind ? ts.SyntaxKind[i.kind] : i.kind));
+                }
+                var result = transformTopLevelDeclaration(i, /*privateDeclaration*/ true);
+                lateStatementReplacementMap.set("" + ts.getOriginalNodeId(i), result);
+            }
+            // And lastly, we need to get the final form of all those indetermine import declarations from before and add them to the output list
+            // (and remove them from the set to examine for outter declarations)
+            return ts.visitNodes(statements, visitLateVisibilityMarkedStatements);
+            function visitLateVisibilityMarkedStatements(statement) {
+                if (ts.isLateVisibilityPaintedStatement(statement)) {
+                    var key = "" + ts.getOriginalNodeId(statement);
+                    if (lateStatementReplacementMap.has(key)) {
+                        var result = lateStatementReplacementMap.get(key);
+                        lateStatementReplacementMap.delete(key);
+                        if (result && ts.isSourceFile(statement.parent)) {
+                            if (ts.isArray(result) ? ts.some(result, needsScopeMarker) : needsScopeMarker(result)) {
+                                // Top-level declarations in .d.ts files are always considered exported even without a modifier unless there's an export assignment or specifier
+                                needsScopeFixMarker = true;
+                            }
+                            if (ts.isArray(result) ? ts.some(result, isExternalModuleIndicator) : isExternalModuleIndicator(result)) {
+                                resultHasExternalModuleIndicator = true;
+                            }
+                        }
+                        return result;
+                    }
+                }
+                return statement;
+            }
+        }
+        function isExternalModuleIndicator(result) {
+            // Exported top-level member indicates moduleness
+            return ts.isAnyImportOrReExport(result) || ts.isExportAssignment(result) || ts.hasModifier(result, 1 /* Export */);
+        }
+        function needsScopeMarker(result) {
+            return !ts.isAnyImportOrReExport(result) && !ts.isExportAssignment(result) && !ts.hasModifier(result, 1 /* Export */) && !ts.isAmbientModule(result);
+        }
+        function visitDeclarationSubtree(input) {
+            if (shouldStripInternal(input))
+                return;
+            if (ts.isDeclaration(input)) {
+                if (isDeclarationAndNotVisible(input))
+                    return;
+                if (ts.hasDynamicName(input) && !resolver.isLateBound(ts.getParseTreeNode(input))) {
+                    return;
+                }
+            }
+            // Elide implementation signatures from overload sets
+            if (ts.isFunctionLike(input) && resolver.isImplementationOfOverload(input))
+                return;
+            // Elide semicolon class statements
+            if (ts.isSemicolonClassElement(input))
+                return;
+            var previousEnclosingDeclaration;
+            if (isEnclosingDeclaration(input)) {
+                previousEnclosingDeclaration = enclosingDeclaration;
+                enclosingDeclaration = input;
+            }
+            var oldDiag = getSymbolAccessibilityDiagnostic;
+            // Emit methods which are private as properties with no type information
+            if (ts.isMethodDeclaration(input) || ts.isMethodSignature(input)) {
+                if (ts.hasModifier(input, 8 /* Private */)) {
+                    if (input.symbol && input.symbol.declarations && input.symbol.declarations[0] !== input)
+                        return; // Elide all but the first overload
+                    return cleanup(ts.createProperty(/*decorators*/ undefined, ensureModifiers(input), input.name, /*questionToken*/ undefined, /*type*/ undefined, /*initializer*/ undefined));
+                }
+            }
+            var canProdiceDiagnostic = ts.canProduceDiagnostics(input);
+            if (canProdiceDiagnostic && !suppressNewDiagnosticContexts) {
+                getSymbolAccessibilityDiagnostic = ts.createGetSymbolAccessibilityDiagnosticForNode(input);
+            }
+            if (ts.isTypeQueryNode(input)) {
+                checkEntityNameVisibility(input.exprName, enclosingDeclaration);
+            }
+            var oldWithinObjectLiteralType = suppressNewDiagnosticContexts;
+            var shouldEnterSuppressNewDiagnosticsContextContext = ((input.kind === 166 /* TypeLiteral */ || input.kind === 177 /* MappedType */) && input.parent.kind !== 237 /* TypeAliasDeclaration */);
+            if (shouldEnterSuppressNewDiagnosticsContextContext) {
+                // We stop making new diagnostic contexts within object literal types. Unless it's an object type on the RHS of a type alias declaration. Then we do.
+                suppressNewDiagnosticContexts = true;
+            }
+            if (isProcessedComponent(input)) {
+                switch (input.kind) {
+                    case 207 /* ExpressionWithTypeArguments */: {
+                        if ((ts.isEntityName(input.expression) || ts.isEntityNameExpression(input.expression))) {
+                            checkEntityNameVisibility(input.expression, enclosingDeclaration);
+                        }
+                        var node = ts.visitEachChild(input, visitDeclarationSubtree, context);
+                        return cleanup(ts.updateExpressionWithTypeArguments(node, ts.parenthesizeTypeParameters(node.typeArguments), node.expression));
+                    }
+                    case 162 /* TypeReference */: {
+                        checkEntityNameVisibility(input.typeName, enclosingDeclaration);
+                        var node = ts.visitEachChild(input, visitDeclarationSubtree, context);
+                        return cleanup(ts.updateTypeReferenceNode(node, node.typeName, ts.parenthesizeTypeParameters(node.typeArguments)));
+                    }
+                    case 159 /* ConstructSignature */:
+                        return cleanup(ts.updateConstructSignature(input, ensureTypeParams(input, input.typeParameters), updateParamsList(input, input.parameters), ensureType(input, input.type)));
+                    case 155 /* Constructor */: {
+                        var isPrivate = ts.hasModifier(input, 8 /* Private */);
+                        // A constructor declaration may not have a type annotation
+                        var ctor = ts.createSignatureDeclaration(155 /* Constructor */, isPrivate ? undefined : ensureTypeParams(input, input.typeParameters), 
+                        // TODO: GH#18217
+                        isPrivate ? undefined : updateParamsList(input, input.parameters, 0 /* None */), 
+                        /*type*/ undefined);
+                        ctor.modifiers = ts.createNodeArray(ensureModifiers(input));
+                        return cleanup(ctor);
+                    }
+                    case 154 /* MethodDeclaration */: {
+                        var sig = ts.createSignatureDeclaration(153 /* MethodSignature */, ensureTypeParams(input, input.typeParameters), updateParamsList(input, input.parameters), ensureType(input, input.type));
+                        sig.name = input.name;
+                        sig.modifiers = ts.createNodeArray(ensureModifiers(input));
+                        sig.questionToken = input.questionToken;
+                        return cleanup(sig);
+                    }
+                    case 156 /* GetAccessor */: {
+                        var newNode = ensureAccessor(input);
+                        return cleanup(newNode);
+                    }
+                    case 157 /* SetAccessor */: {
+                        var newNode = ensureAccessor(input);
+                        return cleanup(newNode);
+                    }
+                    case 152 /* PropertyDeclaration */:
+                        return cleanup(ts.updateProperty(input, 
+                        /*decorators*/ undefined, ensureModifiers(input), input.name, input.questionToken, !ts.hasModifier(input, 8 /* Private */) ? ensureType(input, input.type) : undefined, ensureNoInitializer(input)));
+                    case 151 /* PropertySignature */:
+                        return cleanup(ts.updatePropertySignature(input, ensureModifiers(input), input.name, input.questionToken, !ts.hasModifier(input, 8 /* Private */) ? ensureType(input, input.type) : undefined, ensureNoInitializer(input)));
+                    case 153 /* MethodSignature */: {
+                        return cleanup(ts.updateMethodSignature(input, ensureTypeParams(input, input.typeParameters), updateParamsList(input, input.parameters), ensureType(input, input.type), input.name, input.questionToken));
+                    }
+                    case 158 /* CallSignature */: {
+                        return cleanup(ts.updateCallSignature(input, ensureTypeParams(input, input.typeParameters), updateParamsList(input, input.parameters), ensureType(input, input.type)));
+                    }
+                    case 160 /* IndexSignature */: {
+                        return cleanup(ts.updateIndexSignature(input, 
+                        /*decorators*/ undefined, ensureModifiers(input), updateParamsList(input, input.parameters), ts.visitNode(input.type, visitDeclarationSubtree) || ts.createKeywordTypeNode(119 /* AnyKeyword */)));
+                    }
+                    case 232 /* VariableDeclaration */: {
+                        if (ts.isBindingPattern(input.name)) {
+                            return recreateBindingPattern(input.name);
+                        }
+                        shouldEnterSuppressNewDiagnosticsContextContext = true;
+                        suppressNewDiagnosticContexts = true; // Variable declaration types also suppress new diagnostic contexts, provided the contexts wouldn't be made for binding pattern types
+                        return cleanup(ts.updateVariableDeclaration(input, input.name, ensureType(input, input.type), ensureNoInitializer(input)));
+                    }
+                    case 148 /* TypeParameter */: {
+                        if (isPrivateMethodTypeParameter(input) && (input.default || input.constraint)) {
+                            return cleanup(ts.updateTypeParameterDeclaration(input, input.name, /*constraint*/ undefined, /*defaultType*/ undefined));
+                        }
+                        return cleanup(ts.visitEachChild(input, visitDeclarationSubtree, context));
+                    }
+                    case 171 /* ConditionalType */: {
+                        // We have to process conditional types in a special way because for visibility purposes we need to push a new enclosingDeclaration
+                        // just for the `infer` types in the true branch. It's an implicit declaration scope that only applies to _part_ of the type.
+                        var checkType = ts.visitNode(input.checkType, visitDeclarationSubtree);
+                        var extendsType = ts.visitNode(input.extendsType, visitDeclarationSubtree);
+                        var oldEnclosingDecl = enclosingDeclaration;
+                        enclosingDeclaration = input.trueType;
+                        var trueType = ts.visitNode(input.trueType, visitDeclarationSubtree);
+                        enclosingDeclaration = oldEnclosingDecl;
+                        var falseType = ts.visitNode(input.falseType, visitDeclarationSubtree);
+                        return cleanup(ts.updateConditionalTypeNode(input, checkType, extendsType, trueType, falseType));
+                    }
+                    case 163 /* FunctionType */: {
+                        return cleanup(ts.updateFunctionTypeNode(input, ts.visitNodes(input.typeParameters, visitDeclarationSubtree), updateParamsList(input, input.parameters), ts.visitNode(input.type, visitDeclarationSubtree)));
+                    }
+                    case 164 /* ConstructorType */: {
+                        return cleanup(ts.updateConstructorTypeNode(input, ts.visitNodes(input.typeParameters, visitDeclarationSubtree), updateParamsList(input, input.parameters), ts.visitNode(input.type, visitDeclarationSubtree)));
+                    }
+                    case 179 /* ImportType */: {
+                        if (!ts.isLiteralImportTypeNode(input))
+                            return cleanup(input);
+                        return cleanup(ts.updateImportTypeNode(input, ts.updateLiteralTypeNode(input.argument, rewriteModuleSpecifier(input, input.argument.literal)), input.qualifier, ts.visitNodes(input.typeArguments, visitDeclarationSubtree, ts.isTypeNode), input.isTypeOf));
+                    }
+                    default: ts.Debug.assertNever(input, "Attempted to process unhandled node kind: " + ts.SyntaxKind[input.kind]);
+                }
+            }
+            return cleanup(ts.visitEachChild(input, visitDeclarationSubtree, context));
+            function cleanup(returnValue) {
+                if (returnValue && canProdiceDiagnostic && ts.hasDynamicName(input)) {
+                    checkName(input);
+                }
+                if (isEnclosingDeclaration(input)) {
+                    enclosingDeclaration = previousEnclosingDeclaration;
+                }
+                if (canProdiceDiagnostic && !suppressNewDiagnosticContexts) {
+                    getSymbolAccessibilityDiagnostic = oldDiag;
+                }
+                if (shouldEnterSuppressNewDiagnosticsContextContext) {
+                    suppressNewDiagnosticContexts = oldWithinObjectLiteralType;
+                }
+                if (returnValue === input) {
+                    return returnValue;
+                }
+                return returnValue && ts.setOriginalNode(preserveJsDoc(returnValue, input), input);
+            }
+        }
+        function isPrivateMethodTypeParameter(node) {
+            return node.parent.kind === 154 /* MethodDeclaration */ && ts.hasModifier(node.parent, 8 /* Private */);
+        }
+        function visitDeclarationStatements(input) {
+            if (!isPreservedDeclarationStatement(input)) {
+                // return undefined for unmatched kinds to omit them from the tree
+                return;
+            }
+            if (shouldStripInternal(input))
+                return;
+            switch (input.kind) {
+                case 250 /* ExportDeclaration */: {
+                    if (ts.isSourceFile(input.parent)) {
+                        resultHasExternalModuleIndicator = true;
+                        resultHasScopeMarker = true;
+                    }
+                    // Always visible if the parent node isn't dropped for being not visible
+                    // Rewrite external module names if necessary
+                    return ts.updateExportDeclaration(input, /*decorators*/ undefined, input.modifiers, input.exportClause, rewriteModuleSpecifier(input, input.moduleSpecifier));
+                }
+                case 249 /* ExportAssignment */: {
+                    // Always visible if the parent node isn't dropped for being not visible
+                    if (ts.isSourceFile(input.parent)) {
+                        resultHasExternalModuleIndicator = true;
+                        resultHasScopeMarker = true;
+                    }
+                    if (input.expression.kind === 71 /* Identifier */) {
+                        return input;
+                    }
+                    else {
+                        var newId = ts.createOptimisticUniqueName("_default");
+                        getSymbolAccessibilityDiagnostic = function () { return ({
+                            diagnosticMessage: ts.Diagnostics.Default_export_of_the_module_has_or_is_using_private_name_0,
+                            errorNode: input
+                        }); };
+                        var varDecl = ts.createVariableDeclaration(newId, resolver.createTypeOfExpression(input.expression, input, declarationEmitNodeBuilderFlags, symbolTracker), /*initializer*/ undefined);
+                        var statement = ts.createVariableStatement(needsDeclare ? [ts.createModifier(124 /* DeclareKeyword */)] : [], ts.createVariableDeclarationList([varDecl], 2 /* Const */));
+                        return [statement, ts.updateExportAssignment(input, input.decorators, input.modifiers, newId)];
+                    }
+                }
+            }
+            var result = transformTopLevelDeclaration(input);
+            // Don't actually transform yet; just leave as original node - will be elided/swapped by late pass
+            lateStatementReplacementMap.set("" + ts.getOriginalNodeId(input), result);
+            return input;
+        }
+        function transformTopLevelDeclaration(input, isPrivate) {
+            if (shouldStripInternal(input))
+                return;
+            switch (input.kind) {
+                case 243 /* ImportEqualsDeclaration */: {
+                    return transformImportEqualsDeclaration(input);
+                }
+                case 244 /* ImportDeclaration */: {
+                    return transformImportDeclaration(input);
+                }
+            }
+            if (ts.isDeclaration(input) && isDeclarationAndNotVisible(input))
+                return;
+            // Elide implementation signatures from overload sets
+            if (ts.isFunctionLike(input) && resolver.isImplementationOfOverload(input))
+                return;
+            var previousEnclosingDeclaration;
+            if (isEnclosingDeclaration(input)) {
+                previousEnclosingDeclaration = enclosingDeclaration;
+                enclosingDeclaration = input;
+            }
+            var canProdiceDiagnostic = ts.canProduceDiagnostics(input);
+            var oldDiag = getSymbolAccessibilityDiagnostic;
+            if (canProdiceDiagnostic) {
+                getSymbolAccessibilityDiagnostic = ts.createGetSymbolAccessibilityDiagnosticForNode(input);
+            }
+            var previousNeedsDeclare = needsDeclare;
+            switch (input.kind) {
+                case 237 /* TypeAliasDeclaration */: // Type aliases get `declare`d if need be (for legacy support), but that's all
+                    return cleanup(ts.updateTypeAliasDeclaration(input, 
+                    /*decorators*/ undefined, ensureModifiers(input, isPrivate), input.name, ts.visitNodes(input.typeParameters, visitDeclarationSubtree, ts.isTypeParameterDeclaration), ts.visitNode(input.type, visitDeclarationSubtree, ts.isTypeNode)));
+                case 236 /* InterfaceDeclaration */: {
+                    return cleanup(ts.updateInterfaceDeclaration(input, 
+                    /*decorators*/ undefined, ensureModifiers(input, isPrivate), input.name, ensureTypeParams(input, input.typeParameters), transformHeritageClauses(input.heritageClauses), ts.visitNodes(input.members, visitDeclarationSubtree)));
+                }
+                case 234 /* FunctionDeclaration */: {
+                    // Generators lose their generator-ness, excepting their return type
+                    return cleanup(ts.updateFunctionDeclaration(input, 
+                    /*decorators*/ undefined, ensureModifiers(input, isPrivate), 
+                    /*asteriskToken*/ undefined, input.name, ensureTypeParams(input, input.typeParameters), updateParamsList(input, input.parameters), ensureType(input, input.type), 
+                    /*body*/ undefined));
+                }
+                case 239 /* ModuleDeclaration */: {
+                    needsDeclare = false;
+                    var inner = input.body;
+                    if (inner && inner.kind === 240 /* ModuleBlock */) {
+                        var statements = ts.visitNodes(inner.statements, visitDeclarationStatements);
+                        var body = ts.updateModuleBlock(inner, transformAndReplaceLatePaintedStatements(statements));
+                        needsDeclare = previousNeedsDeclare;
+                        var mods = ensureModifiers(input, isPrivate);
+                        return cleanup(ts.updateModuleDeclaration(input, 
+                        /*decorators*/ undefined, mods, ts.isExternalModuleAugmentation(input) ? rewriteModuleSpecifier(input, input.name) : input.name, body));
+                    }
+                    else {
+                        needsDeclare = previousNeedsDeclare;
+                        var mods = ensureModifiers(input, isPrivate);
+                        needsDeclare = false;
+                        ts.visitNode(inner, visitDeclarationStatements);
+                        // eagerly transform nested namespaces (the nesting doesn't need any elision or painting done)
+                        var id = "" + ts.getOriginalNodeId(inner); // TODO: GH#18217
+                        var body = lateStatementReplacementMap.get(id);
+                        lateStatementReplacementMap.delete(id);
+                        return cleanup(ts.updateModuleDeclaration(input, 
+                        /*decorators*/ undefined, mods, input.name, body));
+                    }
+                }
+                case 235 /* ClassDeclaration */: {
+                    var modifiers = ts.createNodeArray(ensureModifiers(input, isPrivate));
+                    var typeParameters = ensureTypeParams(input, input.typeParameters);
+                    var ctor = ts.getFirstConstructorWithBody(input);
+                    var parameterProperties = void 0;
+                    if (ctor) {
+                        var oldDiag_1 = getSymbolAccessibilityDiagnostic;
+                        parameterProperties = ts.compact(ts.flatMap(ctor.parameters, function (param) {
+                            if (!ts.hasModifier(param, 92 /* ParameterPropertyModifier */))
+                                return;
+                            getSymbolAccessibilityDiagnostic = ts.createGetSymbolAccessibilityDiagnosticForNode(param);
+                            if (param.name.kind === 71 /* Identifier */) {
+                                return preserveJsDoc(ts.createProperty(
+                                /*decorators*/ undefined, ensureModifiers(param), param.name, param.questionToken, ensureType(param, param.type), ensureNoInitializer(param)), param);
+                            }
+                            else {
+                                // Pattern - this is currently an error, but we emit declarations for it somewhat correctly
+                                return walkBindingPattern(param.name);
+                            }
+                            function walkBindingPattern(pattern) {
+                                var elems;
+                                for (var _i = 0, _a = pattern.elements; _i < _a.length; _i++) {
+                                    var elem = _a[_i];
+                                    if (ts.isOmittedExpression(elem))
+                                        continue;
+                                    if (ts.isBindingPattern(elem.name)) {
+                                        elems = ts.concatenate(elems, walkBindingPattern(elem.name));
+                                    }
+                                    elems = elems || [];
+                                    elems.push(ts.createProperty(
+                                    /*decorators*/ undefined, ensureModifiers(param), elem.name, 
+                                    /*questionToken*/ undefined, ensureType(elem, /*type*/ undefined), 
+                                    /*initializer*/ undefined));
+                                }
+                                return elems;
+                            }
+                        }));
+                        getSymbolAccessibilityDiagnostic = oldDiag_1;
+                    }
+                    var members = ts.createNodeArray(ts.concatenate(parameterProperties, ts.visitNodes(input.members, visitDeclarationSubtree)));
+                    var extendsClause_1 = ts.getClassExtendsHeritageClauseElement(input);
+                    if (extendsClause_1 && !ts.isEntityNameExpression(extendsClause_1.expression) && extendsClause_1.expression.kind !== 95 /* NullKeyword */) {
+                        // We must add a temporary declaration for the extends clause expression
+                        var newId_1 = ts.createOptimisticUniqueName(ts.unescapeLeadingUnderscores(input.name.escapedText) + "_base"); // TODO: GH#18217
+                        getSymbolAccessibilityDiagnostic = function () { return ({
+                            diagnosticMessage: ts.Diagnostics.extends_clause_of_exported_class_0_has_or_is_using_private_name_1,
+                            errorNode: extendsClause_1,
+                            typeName: input.name
+                        }); };
+                        var varDecl = ts.createVariableDeclaration(newId_1, resolver.createTypeOfExpression(extendsClause_1.expression, input, declarationEmitNodeBuilderFlags, symbolTracker), /*initializer*/ undefined);
+                        var statement = ts.createVariableStatement(needsDeclare ? [ts.createModifier(124 /* DeclareKeyword */)] : [], ts.createVariableDeclarationList([varDecl], 2 /* Const */));
+                        var heritageClauses = ts.createNodeArray(ts.map(input.heritageClauses, function (clause) {
+                            if (clause.token === 85 /* ExtendsKeyword */) {
+                                var oldDiag_2 = getSymbolAccessibilityDiagnostic;
+                                getSymbolAccessibilityDiagnostic = ts.createGetSymbolAccessibilityDiagnosticForNode(clause.types[0]);
+                                var newClause = ts.updateHeritageClause(clause, ts.map(clause.types, function (t) { return ts.updateExpressionWithTypeArguments(t, ts.visitNodes(t.typeArguments, visitDeclarationSubtree), newId_1); }));
+                                getSymbolAccessibilityDiagnostic = oldDiag_2;
+                                return newClause;
+                            }
+                            return ts.updateHeritageClause(clause, ts.visitNodes(ts.createNodeArray(ts.filter(clause.types, function (t) { return ts.isEntityNameExpression(t.expression) || t.expression.kind === 95 /* NullKeyword */; })), visitDeclarationSubtree));
+                        }));
+                        return [statement, cleanup(ts.updateClassDeclaration(input, 
+                            /*decorators*/ undefined, modifiers, input.name, typeParameters, heritageClauses, members))]; // TODO: GH#18217
+                    }
+                    else {
+                        var heritageClauses = transformHeritageClauses(input.heritageClauses);
+                        return cleanup(ts.updateClassDeclaration(input, 
+                        /*decorators*/ undefined, modifiers, input.name, typeParameters, heritageClauses, members));
+                    }
+                }
+                case 214 /* VariableStatement */: {
+                    return cleanup(transformVariableStatement(input, isPrivate));
+                }
+                case 238 /* EnumDeclaration */: {
+                    return cleanup(ts.updateEnumDeclaration(input, /*decorators*/ undefined, ts.createNodeArray(ensureModifiers(input, isPrivate)), input.name, ts.createNodeArray(ts.mapDefined(input.members, function (m) {
+                        if (shouldStripInternal(m))
+                            return;
+                        // Rewrite enum values to their constants, if available
+                        var constValue = resolver.getConstantValue(m);
+                        return preserveJsDoc(ts.updateEnumMember(m, m.name, constValue !== undefined ? ts.createLiteral(constValue) : undefined), m);
+                    }))));
+                }
+            }
+            // Anything left unhandled is an error, so this should be unreachable
+            return ts.Debug.assertNever(input, "Unhandled top-level node in declaration emit: " + ts.SyntaxKind[input.kind]);
+            function cleanup(node) {
+                if (isEnclosingDeclaration(input)) {
+                    enclosingDeclaration = previousEnclosingDeclaration;
+                }
+                if (canProdiceDiagnostic) {
+                    getSymbolAccessibilityDiagnostic = oldDiag;
+                }
+                if (input.kind === 239 /* ModuleDeclaration */) {
+                    needsDeclare = previousNeedsDeclare;
+                }
+                if (node === input) {
+                    return node;
+                }
+                return node && ts.setOriginalNode(preserveJsDoc(node, input), input);
+            }
+        }
+        function transformVariableStatement(input, privateDeclaration) {
+            if (!ts.forEach(input.declarationList.declarations, getBindingNameVisible))
+                return;
+            var nodes = ts.visitNodes(input.declarationList.declarations, visitDeclarationSubtree);
+            if (!ts.length(nodes))
+                return;
+            return ts.updateVariableStatement(input, ts.createNodeArray(ensureModifiers(input, privateDeclaration)), ts.updateVariableDeclarationList(input.declarationList, nodes));
+        }
+        function recreateBindingPattern(d) {
+            return ts.flatten(ts.mapDefined(d.elements, function (e) { return recreateBindingElement(e); }));
+        }
+        function recreateBindingElement(e) {
+            if (e.kind === 206 /* OmittedExpression */) {
+                return;
+            }
+            if (e.name) {
+                if (!getBindingNameVisible(e))
+                    return;
+                if (ts.isBindingPattern(e.name)) {
+                    return recreateBindingPattern(e.name);
+                }
+                else {
+                    return ts.createVariableDeclaration(e.name, ensureType(e, /*type*/ undefined), /*initializer*/ undefined);
+                }
+            }
+        }
+        function checkName(node) {
+            var oldDiag;
+            if (!suppressNewDiagnosticContexts) {
+                oldDiag = getSymbolAccessibilityDiagnostic;
+                getSymbolAccessibilityDiagnostic = ts.createGetSymbolAccessibilityDiagnosticForNodeName(node);
+            }
+            errorNameNode = node.name;
+            ts.Debug.assert(resolver.isLateBound(ts.getParseTreeNode(node))); // Should only be called with dynamic names
+            var decl = node;
+            var entityName = decl.name.expression;
+            checkEntityNameVisibility(entityName, enclosingDeclaration);
+            if (!suppressNewDiagnosticContexts) {
+                getSymbolAccessibilityDiagnostic = oldDiag;
+            }
+            errorNameNode = undefined;
+        }
+        function hasInternalAnnotation(range) {
+            var comment = currentSourceFile.text.substring(range.pos, range.end);
+            return ts.stringContains(comment, "@internal");
+        }
+        function shouldStripInternal(node) {
+            if (stripInternal && node) {
+                var leadingCommentRanges = ts.getLeadingCommentRangesOfNode(ts.getParseTreeNode(node), currentSourceFile);
+                if (ts.forEach(leadingCommentRanges, hasInternalAnnotation)) {
+                    return true;
+                }
+            }
+            return false;
+        }
+        function ensureModifiers(node, privateDeclaration) {
+            var currentFlags = ts.getModifierFlags(node);
+            var newFlags = ensureModifierFlags(node, privateDeclaration);
+            if (currentFlags === newFlags) {
+                return node.modifiers;
+            }
+            return ts.createModifiersFromModifierFlags(newFlags);
+        }
+        function ensureModifierFlags(node, privateDeclaration) {
+            var mask = 3071 /* All */ ^ (4 /* Public */ | 256 /* Async */); // No async modifiers in declaration files
+            var additions = (needsDeclare && !isAlwaysType(node)) ? 2 /* Ambient */ : 0 /* None */;
+            var parentIsFile = node.parent.kind === 274 /* SourceFile */;
+            if (!parentIsFile || (isBundledEmit && parentIsFile && ts.isExternalModule(node.parent))) {
+                mask ^= ((privateDeclaration || (isBundledEmit && parentIsFile) ? 0 : 1 /* Export */) | 512 /* Default */ | 2 /* Ambient */);
+                additions = 0 /* None */;
+            }
+            return maskModifierFlags(node, mask, additions);
+        }
+        function ensureAccessor(node) {
+            var accessors = resolver.getAllAccessorDeclarations(node);
+            if (node.kind !== accessors.firstAccessor.kind) {
+                return;
+            }
+            var accessorType = getTypeAnnotationFromAccessor(node);
+            if (!accessorType && accessors.secondAccessor) {
+                accessorType = getTypeAnnotationFromAccessor(accessors.secondAccessor);
+                // If we end up pulling the type from the second accessor, we also need to change the diagnostic context to get the expected error message
+                getSymbolAccessibilityDiagnostic = ts.createGetSymbolAccessibilityDiagnosticForNode(accessors.secondAccessor);
+            }
+            var prop = ts.createProperty(/*decorators*/ undefined, maskModifiers(node, /*mask*/ undefined, (!accessors.setAccessor) ? 64 /* Readonly */ : 0 /* None */), node.name, node.questionToken, ensureType(node, accessorType), /*initializer*/ undefined);
+            var leadingsSyntheticCommentRanges = accessors.secondAccessor && ts.getLeadingCommentRangesOfNode(accessors.secondAccessor, currentSourceFile);
+            if (leadingsSyntheticCommentRanges) {
+                var _loop_10 = function (range) {
+                    if (range.kind === 3 /* MultiLineCommentTrivia */) {
+                        var text = currentSourceFile.text.slice(range.pos + 2, range.end - 2);
+                        var lines = text.split(/\r\n?|\n/g);
+                        if (lines.length > 1) {
+                            var lastLines = lines.slice(1);
+                            var indentation_1 = ts.guessIndentation(lastLines);
+                            text = [lines[0]].concat(ts.map(lastLines, function (l) { return l.slice(indentation_1); })).join(newLine);
+                        }
+                        ts.addSyntheticLeadingComment(prop, range.kind, text, range.hasTrailingNewLine);
+                    }
+                };
+                for (var _i = 0, leadingsSyntheticCommentRanges_1 = leadingsSyntheticCommentRanges; _i < leadingsSyntheticCommentRanges_1.length; _i++) {
+                    var range = leadingsSyntheticCommentRanges_1[_i];
+                    _loop_10(range);
+                }
+            }
+            return prop;
+        }
+        function transformHeritageClauses(nodes) {
+            return ts.createNodeArray(ts.filter(ts.map(nodes, function (clause) { return ts.updateHeritageClause(clause, ts.visitNodes(ts.createNodeArray(ts.filter(clause.types, function (t) {
+                return ts.isEntityNameExpression(t.expression) || (clause.token === 85 /* ExtendsKeyword */ && t.expression.kind === 95 /* NullKeyword */);
+            })), visitDeclarationSubtree)); }), function (clause) { return clause.types && !!clause.types.length; }));
+        }
+    }
+    ts.transformDeclarations = transformDeclarations;
+    function isAlwaysType(node) {
+        if (node.kind === 236 /* InterfaceDeclaration */) {
+            return true;
+        }
+        return false;
+    }
+    // Elide "public" modifier, as it is the default
+    function maskModifiers(node, modifierMask, modifierAdditions) {
+        return ts.createModifiersFromModifierFlags(maskModifierFlags(node, modifierMask, modifierAdditions));
+    }
+    function maskModifierFlags(node, modifierMask, modifierAdditions) {
+        if (modifierMask === void 0) { modifierMask = 3071 /* All */ ^ 4 /* Public */; }
+        if (modifierAdditions === void 0) { modifierAdditions = 0 /* None */; }
+        var flags = (ts.getModifierFlags(node) & modifierMask) | modifierAdditions;
+        if (flags & 512 /* Default */ && flags & 2 /* Ambient */) {
+            flags ^= 2 /* Ambient */; // `declare` is never required alongside `default` (and would be an error if printed)
+        }
+        return flags;
+    }
+    function getTypeAnnotationFromAccessor(accessor) {
+        if (accessor) {
+            return accessor.kind === 156 /* GetAccessor */
+                ? accessor.type // Getter - return type
+                : accessor.parameters.length > 0
+                    ? accessor.parameters[0].type // Setter parameter type
+                    : undefined;
+        }
+    }
+    function canHaveLiteralInitializer(node) {
+        switch (node.kind) {
+            case 232 /* VariableDeclaration */:
+            case 152 /* PropertyDeclaration */:
+            case 151 /* PropertySignature */:
+            case 149 /* Parameter */:
+                return true;
+        }
+        return false;
+    }
+    function isPreservedDeclarationStatement(node) {
+        switch (node.kind) {
+            case 234 /* FunctionDeclaration */:
+            case 239 /* ModuleDeclaration */:
+            case 243 /* ImportEqualsDeclaration */:
+            case 236 /* InterfaceDeclaration */:
+            case 235 /* ClassDeclaration */:
+            case 237 /* TypeAliasDeclaration */:
+            case 238 /* EnumDeclaration */:
+            case 214 /* VariableStatement */:
+            case 244 /* ImportDeclaration */:
+            case 250 /* ExportDeclaration */:
+            case 249 /* ExportAssignment */:
+                return true;
+        }
+        return false;
+    }
+    function isProcessedComponent(node) {
+        switch (node.kind) {
+            case 159 /* ConstructSignature */:
+            case 155 /* Constructor */:
+            case 154 /* MethodDeclaration */:
+            case 156 /* GetAccessor */:
+            case 157 /* SetAccessor */:
+            case 152 /* PropertyDeclaration */:
+            case 151 /* PropertySignature */:
+            case 153 /* MethodSignature */:
+            case 158 /* CallSignature */:
+            case 160 /* IndexSignature */:
+            case 232 /* VariableDeclaration */:
+            case 148 /* TypeParameter */:
+            case 207 /* ExpressionWithTypeArguments */:
+            case 162 /* TypeReference */:
+            case 171 /* ConditionalType */:
+            case 163 /* FunctionType */:
+            case 164 /* ConstructorType */:
+            case 179 /* ImportType */:
+                return true;
+        }
+        return false;
+    }
+})(ts || (ts = {}));
+/* @internal */
+var ts;
+(function (ts) {
+    function getModuleTransformer(moduleKind) {
+        switch (moduleKind) {
+            case ts.ModuleKind.ESNext:
+            case ts.ModuleKind.ES2015:
+                return ts.transformES2015Module;
+            case ts.ModuleKind.System:
+                return ts.transformSystemModule;
+            default:
+                return ts.transformModule;
+        }
+    }
+    var TransformationState;
+    (function (TransformationState) {
+        TransformationState[TransformationState["Uninitialized"] = 0] = "Uninitialized";
+        TransformationState[TransformationState["Initialized"] = 1] = "Initialized";
+        TransformationState[TransformationState["Completed"] = 2] = "Completed";
+        TransformationState[TransformationState["Disposed"] = 3] = "Disposed";
+    })(TransformationState || (TransformationState = {}));
+    var SyntaxKindFeatureFlags;
+    (function (SyntaxKindFeatureFlags) {
+        SyntaxKindFeatureFlags[SyntaxKindFeatureFlags["Substitution"] = 1] = "Substitution";
+        SyntaxKindFeatureFlags[SyntaxKindFeatureFlags["EmitNotifications"] = 2] = "EmitNotifications";
+    })(SyntaxKindFeatureFlags || (SyntaxKindFeatureFlags = {}));
+    function getTransformers(compilerOptions, customTransformers) {
+        var jsx = compilerOptions.jsx;
+        var languageVersion = ts.getEmitScriptTarget(compilerOptions);
+        var moduleKind = ts.getEmitModuleKind(compilerOptions);
+        var transformers = [];
+        ts.addRange(transformers, customTransformers && customTransformers.before);
+        transformers.push(ts.transformTypeScript);
+        if (jsx === 2 /* React */) {
+            transformers.push(ts.transformJsx);
+        }
+        if (languageVersion < 6 /* ESNext */) {
+            transformers.push(ts.transformESNext);
+        }
+        if (languageVersion < 4 /* ES2017 */) {
+            transformers.push(ts.transformES2017);
+        }
+        if (languageVersion < 3 /* ES2016 */) {
+            transformers.push(ts.transformES2016);
+        }
+        if (languageVersion < 2 /* ES2015 */) {
+            transformers.push(ts.transformES2015);
+            transformers.push(ts.transformGenerators);
+        }
+        transformers.push(getModuleTransformer(moduleKind));
+        // The ES5 transformer is last so that it can substitute expressions like `exports.default`
+        // for ES3.
+        if (languageVersion < 1 /* ES5 */) {
+            transformers.push(ts.transformES5);
+        }
+        ts.addRange(transformers, customTransformers && customTransformers.after);
+        return transformers;
+    }
+    ts.getTransformers = getTransformers;
+    /**
+     * Transforms an array of SourceFiles by passing them through each transformer.
+     *
+     * @param resolver The emit resolver provided by the checker.
+     * @param host The emit host object used to interact with the file system.
+     * @param options Compiler options to surface in the `TransformationContext`.
+     * @param nodes An array of nodes to transform.
+     * @param transforms An array of `TransformerFactory` callbacks.
+     * @param allowDtsFiles A value indicating whether to allow the transformation of .d.ts files.
+     */
+    function transformNodes(resolver, host, options, nodes, transformers, allowDtsFiles) {
+        var enabledSyntaxKindFeatures = new Array(305 /* Count */);
+        var lexicalEnvironmentVariableDeclarations;
+        var lexicalEnvironmentFunctionDeclarations;
+        var lexicalEnvironmentVariableDeclarationsStack = [];
+        var lexicalEnvironmentFunctionDeclarationsStack = [];
+        var lexicalEnvironmentStackOffset = 0;
+        var lexicalEnvironmentSuspended = false;
+        var emitHelpers;
+        var onSubstituteNode = function (_, node) { return node; };
+        var onEmitNode = function (hint, node, callback) { return callback(hint, node); };
+        var state = 0 /* Uninitialized */;
+        var diagnostics = [];
+        // The transformation context is provided to each transformer as part of transformer
+        // initialization.
+        var context = {
+            getCompilerOptions: function () { return options; },
+            getEmitResolver: function () { return resolver; },
+            getEmitHost: function () { return host; },
+            startLexicalEnvironment: startLexicalEnvironment,
+            suspendLexicalEnvironment: suspendLexicalEnvironment,
+            resumeLexicalEnvironment: resumeLexicalEnvironment,
+            endLexicalEnvironment: endLexicalEnvironment,
+            hoistVariableDeclaration: hoistVariableDeclaration,
+            hoistFunctionDeclaration: hoistFunctionDeclaration,
+            requestEmitHelper: requestEmitHelper,
+            readEmitHelpers: readEmitHelpers,
+            enableSubstitution: enableSubstitution,
+            enableEmitNotification: enableEmitNotification,
+            isSubstitutionEnabled: isSubstitutionEnabled,
+            isEmitNotificationEnabled: isEmitNotificationEnabled,
+            get onSubstituteNode() { return onSubstituteNode; },
+            set onSubstituteNode(value) {
+                ts.Debug.assert(state < 1 /* Initialized */, "Cannot modify transformation hooks after initialization has completed.");
+                ts.Debug.assert(value !== undefined, "Value must not be 'undefined'");
+                onSubstituteNode = value;
+            },
+            get onEmitNode() { return onEmitNode; },
+            set onEmitNode(value) {
+                ts.Debug.assert(state < 1 /* Initialized */, "Cannot modify transformation hooks after initialization has completed.");
+                ts.Debug.assert(value !== undefined, "Value must not be 'undefined'");
+                onEmitNode = value;
+            },
+            addDiagnostic: function (diag) {
+                diagnostics.push(diag);
+            }
+        };
+        // Ensure the parse tree is clean before applying transformations
+        for (var _i = 0, nodes_4 = nodes; _i < nodes_4.length; _i++) {
+            var node = nodes_4[_i];
+            ts.disposeEmitNodes(ts.getSourceFileOfNode(ts.getParseTreeNode(node)));
+        }
+        ts.performance.mark("beforeTransform");
+        // Chain together and initialize each transformer.
+        var transformation = ts.chain.apply(void 0, transformers)(context);
+        // prevent modification of transformation hooks.
+        state = 1 /* Initialized */;
+        // Transform each node.
+        var transformed = ts.map(nodes, allowDtsFiles ? transformation : transformRoot);
+        // prevent modification of the lexical environment.
+        state = 2 /* Completed */;
+        ts.performance.mark("afterTransform");
+        ts.performance.measure("transformTime", "beforeTransform", "afterTransform");
+        return {
+            transformed: transformed,
+            substituteNode: substituteNode,
+            emitNodeWithNotification: emitNodeWithNotification,
+            dispose: dispose,
+            diagnostics: diagnostics
+        };
+        function transformRoot(node) {
+            return node && (!ts.isSourceFile(node) || !node.isDeclarationFile) ? transformation(node) : node;
+        }
+        /**
+         * Enables expression substitutions in the pretty printer for the provided SyntaxKind.
+         */
+        function enableSubstitution(kind) {
+            ts.Debug.assert(state < 2 /* Completed */, "Cannot modify the transformation context after transformation has completed.");
+            enabledSyntaxKindFeatures[kind] |= 1 /* Substitution */;
+        }
+        /**
+         * Determines whether expression substitutions are enabled for the provided node.
+         */
+        function isSubstitutionEnabled(node) {
+            return (enabledSyntaxKindFeatures[node.kind] & 1 /* Substitution */) !== 0
+                && (ts.getEmitFlags(node) & 4 /* NoSubstitution */) === 0;
+        }
+        /**
+         * Emits a node with possible substitution.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to emit.
+         * @param emitCallback The callback used to emit the node or its substitute.
+         */
+        function substituteNode(hint, node) {
+            ts.Debug.assert(state < 3 /* Disposed */, "Cannot substitute a node after the result is disposed.");
+            return node && isSubstitutionEnabled(node) && onSubstituteNode(hint, node) || node;
+        }
+        /**
+         * Enables before/after emit notifications in the pretty printer for the provided SyntaxKind.
+         */
+        function enableEmitNotification(kind) {
+            ts.Debug.assert(state < 2 /* Completed */, "Cannot modify the transformation context after transformation has completed.");
+            enabledSyntaxKindFeatures[kind] |= 2 /* EmitNotifications */;
+        }
+        /**
+         * Determines whether before/after emit notifications should be raised in the pretty
+         * printer when it emits a node.
+         */
+        function isEmitNotificationEnabled(node) {
+            return (enabledSyntaxKindFeatures[node.kind] & 2 /* EmitNotifications */) !== 0
+                || (ts.getEmitFlags(node) & 2 /* AdviseOnEmitNode */) !== 0;
+        }
+        /**
+         * Emits a node with possible emit notification.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to emit.
+         * @param emitCallback The callback used to emit the node.
+         */
+        function emitNodeWithNotification(hint, node, emitCallback) {
+            ts.Debug.assert(state < 3 /* Disposed */, "Cannot invoke TransformationResult callbacks after the result is disposed.");
+            if (node) {
+                if (isEmitNotificationEnabled(node)) {
+                    onEmitNode(hint, node, emitCallback);
+                }
+                else {
+                    emitCallback(hint, node);
+                }
+            }
+        }
+        /**
+         * Records a hoisted variable declaration for the provided name within a lexical environment.
+         */
+        function hoistVariableDeclaration(name) {
+            ts.Debug.assert(state > 0 /* Uninitialized */, "Cannot modify the lexical environment during initialization.");
+            ts.Debug.assert(state < 2 /* Completed */, "Cannot modify the lexical environment after transformation has completed.");
+            var decl = ts.setEmitFlags(ts.createVariableDeclaration(name), 64 /* NoNestedSourceMaps */);
+            if (!lexicalEnvironmentVariableDeclarations) {
+                lexicalEnvironmentVariableDeclarations = [decl];
+            }
+            else {
+                lexicalEnvironmentVariableDeclarations.push(decl);
+            }
+        }
+        /**
+         * Records a hoisted function declaration within a lexical environment.
+         */
+        function hoistFunctionDeclaration(func) {
+            ts.Debug.assert(state > 0 /* Uninitialized */, "Cannot modify the lexical environment during initialization.");
+            ts.Debug.assert(state < 2 /* Completed */, "Cannot modify the lexical environment after transformation has completed.");
+            if (!lexicalEnvironmentFunctionDeclarations) {
+                lexicalEnvironmentFunctionDeclarations = [func];
+            }
+            else {
+                lexicalEnvironmentFunctionDeclarations.push(func);
+            }
+        }
+        /**
+         * Starts a new lexical environment. Any existing hoisted variable or function declarations
+         * are pushed onto a stack, and the related storage variables are reset.
+         */
+        function startLexicalEnvironment() {
+            ts.Debug.assert(state > 0 /* Uninitialized */, "Cannot modify the lexical environment during initialization.");
+            ts.Debug.assert(state < 2 /* Completed */, "Cannot modify the lexical environment after transformation has completed.");
+            ts.Debug.assert(!lexicalEnvironmentSuspended, "Lexical environment is suspended.");
+            // Save the current lexical environment. Rather than resizing the array we adjust the
+            // stack size variable. This allows us to reuse existing array slots we've
+            // already allocated between transformations to avoid allocation and GC overhead during
+            // transformation.
+            lexicalEnvironmentVariableDeclarationsStack[lexicalEnvironmentStackOffset] = lexicalEnvironmentVariableDeclarations;
+            lexicalEnvironmentFunctionDeclarationsStack[lexicalEnvironmentStackOffset] = lexicalEnvironmentFunctionDeclarations;
+            lexicalEnvironmentStackOffset++;
+            lexicalEnvironmentVariableDeclarations = undefined;
+            lexicalEnvironmentFunctionDeclarations = undefined;
+        }
+        /** Suspends the current lexical environment, usually after visiting a parameter list. */
+        function suspendLexicalEnvironment() {
+            ts.Debug.assert(state > 0 /* Uninitialized */, "Cannot modify the lexical environment during initialization.");
+            ts.Debug.assert(state < 2 /* Completed */, "Cannot modify the lexical environment after transformation has completed.");
+            ts.Debug.assert(!lexicalEnvironmentSuspended, "Lexical environment is already suspended.");
+            lexicalEnvironmentSuspended = true;
+        }
+        /** Resumes a suspended lexical environment, usually before visiting a function body. */
+        function resumeLexicalEnvironment() {
+            ts.Debug.assert(state > 0 /* Uninitialized */, "Cannot modify the lexical environment during initialization.");
+            ts.Debug.assert(state < 2 /* Completed */, "Cannot modify the lexical environment after transformation has completed.");
+            ts.Debug.assert(lexicalEnvironmentSuspended, "Lexical environment is not suspended.");
+            lexicalEnvironmentSuspended = false;
+        }
+        /**
+         * Ends a lexical environment. The previous set of hoisted declarations are restored and
+         * any hoisted declarations added in this environment are returned.
+         */
+        function endLexicalEnvironment() {
+            ts.Debug.assert(state > 0 /* Uninitialized */, "Cannot modify the lexical environment during initialization.");
+            ts.Debug.assert(state < 2 /* Completed */, "Cannot modify the lexical environment after transformation has completed.");
+            ts.Debug.assert(!lexicalEnvironmentSuspended, "Lexical environment is suspended.");
+            var statements;
+            if (lexicalEnvironmentVariableDeclarations || lexicalEnvironmentFunctionDeclarations) {
+                if (lexicalEnvironmentFunctionDeclarations) {
+                    statements = lexicalEnvironmentFunctionDeclarations.slice();
+                }
+                if (lexicalEnvironmentVariableDeclarations) {
+                    var statement = ts.createVariableStatement(
+                    /*modifiers*/ undefined, ts.createVariableDeclarationList(lexicalEnvironmentVariableDeclarations));
+                    if (!statements) {
+                        statements = [statement];
+                    }
+                    else {
+                        statements.push(statement);
+                    }
+                }
+            }
+            // Restore the previous lexical environment.
+            lexicalEnvironmentStackOffset--;
+            lexicalEnvironmentVariableDeclarations = lexicalEnvironmentVariableDeclarationsStack[lexicalEnvironmentStackOffset];
+            lexicalEnvironmentFunctionDeclarations = lexicalEnvironmentFunctionDeclarationsStack[lexicalEnvironmentStackOffset];
+            if (lexicalEnvironmentStackOffset === 0) {
+                lexicalEnvironmentVariableDeclarationsStack = [];
+                lexicalEnvironmentFunctionDeclarationsStack = [];
+            }
+            return statements;
+        }
+        function requestEmitHelper(helper) {
+            ts.Debug.assert(state > 0 /* Uninitialized */, "Cannot modify the transformation context during initialization.");
+            ts.Debug.assert(state < 2 /* Completed */, "Cannot modify the transformation context after transformation has completed.");
+            ts.Debug.assert(!helper.scoped, "Cannot request a scoped emit helper.");
+            emitHelpers = ts.append(emitHelpers, helper);
+        }
+        function readEmitHelpers() {
+            ts.Debug.assert(state > 0 /* Uninitialized */, "Cannot modify the transformation context during initialization.");
+            ts.Debug.assert(state < 2 /* Completed */, "Cannot modify the transformation context after transformation has completed.");
+            var helpers = emitHelpers;
+            emitHelpers = undefined;
+            return helpers;
+        }
+        function dispose() {
+            if (state < 3 /* Disposed */) {
+                // Clean up emit nodes on parse tree
+                for (var _i = 0, nodes_5 = nodes; _i < nodes_5.length; _i++) {
+                    var node = nodes_5[_i];
+                    ts.disposeEmitNodes(ts.getSourceFileOfNode(ts.getParseTreeNode(node)));
+                }
+                // Release references to external entries for GC purposes.
+                lexicalEnvironmentVariableDeclarations = undefined;
+                lexicalEnvironmentVariableDeclarationsStack = undefined;
+                lexicalEnvironmentFunctionDeclarations = undefined;
+                lexicalEnvironmentFunctionDeclarationsStack = undefined;
+                onSubstituteNode = undefined;
+                onEmitNode = undefined;
+                emitHelpers = undefined;
+                // Prevent further use of the transformation result.
+                state = 3 /* Disposed */;
+            }
+        }
+    }
+    ts.transformNodes = transformNodes;
+})(ts || (ts = {}));
+/* @internal */
+var ts;
+(function (ts) {
+    // Used for initialize lastEncodedSourceMapSpan and reset lastEncodedSourceMapSpan when updateLastEncodedAndRecordedSpans
+    var defaultLastEncodedSourceMapSpan = {
+        emittedLine: 1,
+        emittedColumn: 1,
+        sourceLine: 1,
+        sourceColumn: 1,
+        sourceIndex: 0
+    };
+    function createSourceMapWriter(host, writer, compilerOptions) {
+        if (compilerOptions === void 0) { compilerOptions = host.getCompilerOptions(); }
+        var extendedDiagnostics = compilerOptions.extendedDiagnostics;
+        var currentSource;
+        var currentSourceText;
+        var sourceMapDir; // The directory in which sourcemap will be
+        // Current source map file and its index in the sources list
+        var sourceMapSourceIndex;
+        // Last recorded and encoded spans
+        var lastRecordedSourceMapSpan;
+        var lastEncodedSourceMapSpan;
+        var lastEncodedNameIndex;
+        // Source map data
+        var sourceMapData;
+        var sourceMapDataList;
+        var disabled = !(compilerOptions.sourceMap || compilerOptions.inlineSourceMap);
+        var completedSections;
+        var sectionStartLine;
+        var sectionStartColumn;
+        return {
+            initialize: initialize,
+            reset: reset,
+            setSourceFile: setSourceFile,
+            emitPos: emitPos,
+            emitNodeWithSourceMap: emitNodeWithSourceMap,
+            emitTokenWithSourceMap: emitTokenWithSourceMap,
+            getText: getText,
+            getSourceMappingURL: getSourceMappingURL,
+        };
+        /**
+         * Skips trivia such as comments and white-space that can optionally overriden by the source map source
+         */
+        function skipSourceTrivia(pos) {
+            return currentSource.skipTrivia ? currentSource.skipTrivia(pos) : ts.skipTrivia(currentSourceText, pos);
+        }
+        /**
+         * Initialize the SourceMapWriter for a new output file.
+         *
+         * @param filePath The path to the generated output file.
+         * @param sourceMapFilePath The path to the output source map file.
+         * @param sourceFileOrBundle The input source file or bundle for the program.
+         */
+        function initialize(filePath, sourceMapFilePath, sourceFileOrBundle, outputSourceMapDataList) {
+            if (disabled || ts.fileExtensionIs(filePath, ".json" /* Json */)) {
+                return;
+            }
+            if (sourceMapData) {
+                reset();
+            }
+            sourceMapDataList = outputSourceMapDataList;
+            currentSource = undefined;
+            currentSourceText = undefined;
+            // Current source map file and its index in the sources list
+            sourceMapSourceIndex = -1;
+            // Last recorded and encoded spans
+            lastRecordedSourceMapSpan = undefined;
+            lastEncodedSourceMapSpan = defaultLastEncodedSourceMapSpan;
+            lastEncodedNameIndex = 0;
+            // Initialize source map data
+            completedSections = [];
+            sectionStartLine = 1;
+            sectionStartColumn = 1;
+            sourceMapData = {
+                sourceMapFilePath: sourceMapFilePath,
+                jsSourceMappingURL: !compilerOptions.inlineSourceMap ? ts.getBaseFileName(ts.normalizeSlashes(sourceMapFilePath)) : undefined,
+                sourceMapFile: ts.getBaseFileName(ts.normalizeSlashes(filePath)),
+                sourceMapSourceRoot: compilerOptions.sourceRoot || "",
+                sourceMapSources: [],
+                inputSourceFileNames: [],
+                sourceMapNames: [],
+                sourceMapMappings: "",
+                sourceMapSourcesContent: compilerOptions.inlineSources ? [] : undefined,
+                sourceMapDecodedMappings: []
+            };
+            // Normalize source root and make sure it has trailing "/" so that it can be used to combine paths with the
+            // relative paths of the sources list in the sourcemap
+            sourceMapData.sourceMapSourceRoot = ts.normalizeSlashes(sourceMapData.sourceMapSourceRoot);
+            if (sourceMapData.sourceMapSourceRoot.length && sourceMapData.sourceMapSourceRoot.charCodeAt(sourceMapData.sourceMapSourceRoot.length - 1) !== 47 /* slash */) {
+                sourceMapData.sourceMapSourceRoot += ts.directorySeparator;
+            }
+            if (compilerOptions.mapRoot) {
+                sourceMapDir = ts.normalizeSlashes(compilerOptions.mapRoot);
+                if (sourceFileOrBundle.kind === 274 /* SourceFile */) { // emitting single module file
+                    // For modules or multiple emit files the mapRoot will have directory structure like the sources
+                    // So if src\a.ts and src\lib\b.ts are compiled together user would be moving the maps into mapRoot\a.js.map and mapRoot\lib\b.js.map
+                    sourceMapDir = ts.getDirectoryPath(ts.getSourceFilePathInNewDir(sourceFileOrBundle, host, sourceMapDir));
+                }
+                if (!ts.isRootedDiskPath(sourceMapDir) && !ts.isUrl(sourceMapDir)) {
+                    // The relative paths are relative to the common directory
+                    sourceMapDir = ts.combinePaths(host.getCommonSourceDirectory(), sourceMapDir);
+                    sourceMapData.jsSourceMappingURL = ts.getRelativePathToDirectoryOrUrl(ts.getDirectoryPath(ts.normalizePath(filePath)), // get the relative sourceMapDir path based on jsFilePath
+                    ts.combinePaths(sourceMapDir, sourceMapData.jsSourceMappingURL), // this is where user expects to see sourceMap
+                    host.getCurrentDirectory(), host.getCanonicalFileName, 
+                    /*isAbsolutePathAnUrl*/ true);
+                }
+                else {
+                    sourceMapData.jsSourceMappingURL = ts.combinePaths(sourceMapDir, sourceMapData.jsSourceMappingURL);
+                }
+            }
+            else {
+                sourceMapDir = ts.getDirectoryPath(ts.normalizePath(filePath));
+            }
+        }
+        /**
+         * Reset the SourceMapWriter to an empty state.
+         */
+        function reset() {
+            if (disabled) {
+                return;
+            }
+            // Record source map data for the test harness.
+            if (sourceMapDataList) {
+                sourceMapDataList.push(sourceMapData);
+            }
+            currentSource = undefined;
+            sourceMapDir = undefined;
+            sourceMapSourceIndex = undefined;
+            lastRecordedSourceMapSpan = undefined;
+            lastEncodedSourceMapSpan = undefined;
+            lastEncodedNameIndex = undefined;
+            sourceMapData = undefined;
+            sourceMapDataList = undefined;
+            completedSections = undefined;
+            sectionStartLine = undefined;
+            sectionStartColumn = undefined;
+        }
+        function captureSection() {
+            return {
+                version: 3,
+                file: sourceMapData.sourceMapFile,
+                sourceRoot: sourceMapData.sourceMapSourceRoot,
+                sources: sourceMapData.sourceMapSources,
+                names: sourceMapData.sourceMapNames,
+                mappings: sourceMapData.sourceMapMappings,
+                sourcesContent: sourceMapData.sourceMapSourcesContent,
+            };
+        }
+        function resetSectionalData() {
+            sourceMapData.sourceMapSources = [];
+            sourceMapData.sourceMapNames = [];
+            sourceMapData.sourceMapMappings = "";
+            sourceMapData.sourceMapSourcesContent = compilerOptions.inlineSources ? [] : undefined;
+        }
+        function generateMap() {
+            if (completedSections.length) {
+                captureSectionalSpanIfNeeded(/*reset*/ false);
+                return {
+                    version: 3,
+                    file: sourceMapData.sourceMapFile,
+                    sections: completedSections
+                };
+            }
+            else {
+                return captureSection();
+            }
+        }
+        // Encoding for sourcemap span
+        function encodeLastRecordedSourceMapSpan() {
+            if (!lastRecordedSourceMapSpan || lastRecordedSourceMapSpan === lastEncodedSourceMapSpan) {
+                return;
+            }
+            var prevEncodedEmittedColumn = lastEncodedSourceMapSpan.emittedColumn;
+            // Line/Comma delimiters
+            if (lastEncodedSourceMapSpan.emittedLine === lastRecordedSourceMapSpan.emittedLine) {
+                // Emit comma to separate the entry
+                if (sourceMapData.sourceMapMappings) {
+                    sourceMapData.sourceMapMappings += ",";
+                }
+            }
+            else {
+                // Emit line delimiters
+                for (var encodedLine = lastEncodedSourceMapSpan.emittedLine; encodedLine < lastRecordedSourceMapSpan.emittedLine; encodedLine++) {
+                    sourceMapData.sourceMapMappings += ";";
+                }
+                prevEncodedEmittedColumn = 1;
+            }
+            // 1. Relative Column 0 based
+            sourceMapData.sourceMapMappings += base64VLQFormatEncode(lastRecordedSourceMapSpan.emittedColumn - prevEncodedEmittedColumn);
+            // 2. Relative sourceIndex
+            sourceMapData.sourceMapMappings += base64VLQFormatEncode(lastRecordedSourceMapSpan.sourceIndex - lastEncodedSourceMapSpan.sourceIndex);
+            // 3. Relative sourceLine 0 based
+            sourceMapData.sourceMapMappings += base64VLQFormatEncode(lastRecordedSourceMapSpan.sourceLine - lastEncodedSourceMapSpan.sourceLine);
+            // 4. Relative sourceColumn 0 based
+            sourceMapData.sourceMapMappings += base64VLQFormatEncode(lastRecordedSourceMapSpan.sourceColumn - lastEncodedSourceMapSpan.sourceColumn);
+            // 5. Relative namePosition 0 based
+            if (lastRecordedSourceMapSpan.nameIndex >= 0) {
+                ts.Debug.assert(false, "We do not support name index right now, Make sure to update updateLastEncodedAndRecordedSpans when we start using this");
+                sourceMapData.sourceMapMappings += base64VLQFormatEncode(lastRecordedSourceMapSpan.nameIndex - lastEncodedNameIndex);
+                lastEncodedNameIndex = lastRecordedSourceMapSpan.nameIndex;
+            }
+            lastEncodedSourceMapSpan = lastRecordedSourceMapSpan;
+            sourceMapData.sourceMapDecodedMappings.push(lastEncodedSourceMapSpan);
+        }
+        /**
+         * Emits a mapping.
+         *
+         * If the position is synthetic (undefined or a negative value), no mapping will be
+         * created.
+         *
+         * @param pos The position.
+         */
+        function emitPos(pos) {
+            if (disabled || ts.positionIsSynthesized(pos) || isJsonSourceMapSource(currentSource)) {
+                return;
+            }
+            if (extendedDiagnostics) {
+                ts.performance.mark("beforeSourcemap");
+            }
+            var sourceLinePos = ts.getLineAndCharacterOfPosition(currentSource, pos);
+            // Convert the location to be one-based.
+            sourceLinePos.line++;
+            sourceLinePos.character++;
+            var emittedLine = writer.getLine() - sectionStartLine + 1;
+            var emittedColumn = emittedLine === 0 ? (writer.getColumn() - sectionStartColumn + 1) : writer.getColumn();
+            // If this location wasn't recorded or the location in source is going backwards, record the span
+            if (!lastRecordedSourceMapSpan ||
+                lastRecordedSourceMapSpan.emittedLine !== emittedLine ||
+                lastRecordedSourceMapSpan.emittedColumn !== emittedColumn ||
+                (lastRecordedSourceMapSpan.sourceIndex === sourceMapSourceIndex &&
+                    (lastRecordedSourceMapSpan.sourceLine > sourceLinePos.line ||
+                        (lastRecordedSourceMapSpan.sourceLine === sourceLinePos.line && lastRecordedSourceMapSpan.sourceColumn > sourceLinePos.character)))) {
+                // Encode the last recordedSpan before assigning new
+                encodeLastRecordedSourceMapSpan();
+                // New span
+                lastRecordedSourceMapSpan = {
+                    emittedLine: emittedLine,
+                    emittedColumn: emittedColumn,
+                    sourceLine: sourceLinePos.line,
+                    sourceColumn: sourceLinePos.character,
+                    sourceIndex: sourceMapSourceIndex
+                };
+            }
+            else {
+                // Take the new pos instead since there is no change in emittedLine and column since last location
+                lastRecordedSourceMapSpan.sourceLine = sourceLinePos.line;
+                lastRecordedSourceMapSpan.sourceColumn = sourceLinePos.character;
+                lastRecordedSourceMapSpan.sourceIndex = sourceMapSourceIndex;
+            }
+            if (extendedDiagnostics) {
+                ts.performance.mark("afterSourcemap");
+                ts.performance.measure("Source Map", "beforeSourcemap", "afterSourcemap");
+            }
+        }
+        function captureSectionalSpanIfNeeded(reset) {
+            if (lastRecordedSourceMapSpan && lastRecordedSourceMapSpan === lastEncodedSourceMapSpan) { // If we've recorded some spans, save them
+                completedSections.push({ offset: { line: sectionStartLine - 1, column: sectionStartColumn - 1 }, map: captureSection() });
+                if (reset) {
+                    resetSectionalData();
+                }
+            }
+        }
+        /**
+         * Emits a node with possible leading and trailing source maps.
+         *
+         * @param hint A hint as to the intended usage of the node.
+         * @param node The node to emit.
+         * @param emitCallback The callback used to emit the node.
+         */
+        function emitNodeWithSourceMap(hint, node, emitCallback) {
+            if (disabled || ts.isInJsonFile(node)) {
+                return emitCallback(hint, node);
+            }
+            if (node) {
+                if (ts.isUnparsedSource(node) && node.sourceMapText !== undefined) {
+                    captureSectionalSpanIfNeeded(/*reset*/ true);
+                    var text = node.sourceMapText;
+                    var parsed = void 0;
+                    try {
+                        parsed = JSON.parse(text);
+                    }
+                    catch (_a) {
+                        // empty
+                    }
+                    var offset = { line: writer.getLine() - 1, column: writer.getColumn() - 1 };
+                    completedSections.push(parsed
+                        ? {
+                            offset: offset,
+                            map: parsed
+                        }
+                        : {
+                            offset: offset,
+                            // This is just passes the buck on sourcemaps we don't really understand, instead of issuing an error (which would be difficult this late)
+                            url: "data:application/json;charset=utf-8;base64," + ts.base64encode(ts.sys, text)
+                        });
+                    var emitResult = emitCallback(hint, node);
+                    sectionStartLine = writer.getLine();
+                    sectionStartColumn = writer.getColumn();
+                    lastRecordedSourceMapSpan = undefined;
+                    lastEncodedSourceMapSpan = defaultLastEncodedSourceMapSpan;
+                    return emitResult;
+                }
+                var emitNode = node.emitNode;
+                var emitFlags = emitNode && emitNode.flags || 0 /* None */;
+                var range = emitNode && emitNode.sourceMapRange;
+                var _b = range || node, pos = _b.pos, end = _b.end;
+                var source = range && range.source;
+                var oldSource = currentSource;
+                if (source === oldSource)
+                    source = undefined;
+                if (source)
+                    setSourceFile(source);
+                if (node.kind !== 300 /* NotEmittedStatement */
+                    && (emitFlags & 16 /* NoLeadingSourceMap */) === 0
+                    && pos >= 0) {
+                    emitPos(skipSourceTrivia(pos));
+                }
+                if (source)
+                    setSourceFile(oldSource);
+                if (emitFlags & 64 /* NoNestedSourceMaps */) {
+                    disabled = true;
+                    emitCallback(hint, node);
+                    disabled = false;
+                }
+                else {
+                    emitCallback(hint, node);
+                }
+                if (source)
+                    setSourceFile(source);
+                if (node.kind !== 300 /* NotEmittedStatement */
+                    && (emitFlags & 32 /* NoTrailingSourceMap */) === 0
+                    && end >= 0) {
+                    emitPos(end);
+                }
+                if (source)
+                    setSourceFile(oldSource);
+            }
+        }
+        /**
+         * Emits a token of a node with possible leading and trailing source maps.
+         *
+         * @param node The node containing the token.
+         * @param token The token to emit.
+         * @param tokenStartPos The start pos of the token.
+         * @param emitCallback The callback used to emit the token.
+         */
+        function emitTokenWithSourceMap(node, token, writer, tokenPos, emitCallback) {
+            if (disabled || ts.isInJsonFile(node)) {
+                return emitCallback(token, writer, tokenPos);
+            }
+            var emitNode = node && node.emitNode;
+            var emitFlags = emitNode && emitNode.flags || 0 /* None */;
+            var range = emitNode && emitNode.tokenSourceMapRanges && emitNode.tokenSourceMapRanges[token];
+            tokenPos = skipSourceTrivia(range ? range.pos : tokenPos);
+            if ((emitFlags & 128 /* NoTokenLeadingSourceMaps */) === 0 && tokenPos >= 0) {
+                emitPos(tokenPos);
+            }
+            tokenPos = emitCallback(token, writer, tokenPos);
+            if (range)
+                tokenPos = range.end;
+            if ((emitFlags & 256 /* NoTokenTrailingSourceMaps */) === 0 && tokenPos >= 0) {
+                emitPos(tokenPos);
+            }
+            return tokenPos;
+        }
+        function isJsonSourceMapSource(sourceFile) {
+            return ts.fileExtensionIs(sourceFile.fileName, ".json" /* Json */);
+        }
+        /**
+         * Set the current source file.
+         *
+         * @param sourceFile The source file.
+         */
+        function setSourceFile(sourceFile) {
+            if (disabled) {
+                return;
+            }
+            currentSource = sourceFile;
+            currentSourceText = currentSource.text;
+            if (isJsonSourceMapSource(sourceFile)) {
+                return;
+            }
+            // Add the file to tsFilePaths
+            // If sourceroot option: Use the relative path corresponding to the common directory path
+            // otherwise source locations relative to map file location
+            var sourcesDirectoryPath = compilerOptions.sourceRoot ? host.getCommonSourceDirectory() : sourceMapDir;
+            var source = ts.getRelativePathToDirectoryOrUrl(sourcesDirectoryPath, currentSource.fileName, host.getCurrentDirectory(), host.getCanonicalFileName, 
+            /*isAbsolutePathAnUrl*/ true);
+            sourceMapSourceIndex = sourceMapData.sourceMapSources.indexOf(source);
+            if (sourceMapSourceIndex === -1) {
+                sourceMapSourceIndex = sourceMapData.sourceMapSources.length;
+                sourceMapData.sourceMapSources.push(source);
+                // The one that can be used from program to get the actual source file
+                sourceMapData.inputSourceFileNames.push(currentSource.fileName);
+                if (compilerOptions.inlineSources) {
+                    sourceMapData.sourceMapSourcesContent.push(currentSource.text);
+                }
+            }
+        }
+        /**
+         * Gets the text for the source map.
+         */
+        function getText() {
+            if (disabled || isJsonSourceMapSource(currentSource)) {
+                return undefined; // TODO: GH#18217
+            }
+            encodeLastRecordedSourceMapSpan();
+            return JSON.stringify(generateMap());
+        }
+        /**
+         * Gets the SourceMappingURL for the source map.
+         */
+        function getSourceMappingURL() {
+            if (disabled || isJsonSourceMapSource(currentSource)) {
+                return undefined; // TODO: GH#18217
+            }
+            if (compilerOptions.inlineSourceMap) {
+                // Encode the sourceMap into the sourceMap url
+                var base64SourceMapText = ts.base64encode(ts.sys, getText());
+                return sourceMapData.jsSourceMappingURL = "data:application/json;base64," + base64SourceMapText;
+            }
+            else {
+                return sourceMapData.jsSourceMappingURL;
+            }
+        }
+    }
+    ts.createSourceMapWriter = createSourceMapWriter;
+    var base64Chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
+    function base64FormatEncode(inValue) {
+        if (inValue < 64) {
+            return base64Chars.charAt(inValue);
+        }
+        throw TypeError(inValue + ": not a 64 based value");
+    }
+    function base64VLQFormatEncode(inValue) {
+        // Add a new least significant bit that has the sign of the value.
+        // if negative number the least significant bit that gets added to the number has value 1
+        // else least significant bit value that gets added is 0
+        // eg. -1 changes to binary : 01 [1] => 3
+        //     +1 changes to binary : 01 [0] => 2
+        if (inValue < 0) {
+            inValue = ((-inValue) << 1) + 1;
+        }
+        else {
+            inValue = inValue << 1;
+        }
+        // Encode 5 bits at a time starting from least significant bits
+        var encodedStr = "";
+        do {
+            var currentDigit = inValue & 31; // 11111
+            inValue = inValue >> 5;
+            if (inValue > 0) {
+                // There are still more digits to decode, set the msb (6th bit)
+                currentDigit = currentDigit | 32;
+            }
+            encodedStr = encodedStr + base64FormatEncode(currentDigit);
+        } while (inValue > 0);
+        return encodedStr;
+    }
+})(ts || (ts = {}));
+/* @internal */
+var ts;
+(function (ts) {
+    function createCommentWriter(printerOptions, emitPos) {
+        var extendedDiagnostics = printerOptions.extendedDiagnostics;
+        var newLine = ts.getNewLineCharacter(printerOptions);
+        var writer;
+        var containerPos = -1;
+        var containerEnd = -1;
+        var declarationListContainerEnd = -1;
+        var currentSourceFile;
+        var currentText;
+        var currentLineMap;
+        var detachedCommentsInfo;
+        var hasWrittenComment = false;
+        var disabled = !!printerOptions.removeComments;
+        return {
+            reset: reset,
+            setWriter: setWriter,
+            setSourceFile: setSourceFile,
+            emitNodeWithComments: emitNodeWithComments,
+            emitBodyWithDetachedComments: emitBodyWithDetachedComments,
+            emitTrailingCommentsOfPosition: emitTrailingCommentsOfPosition,
+            emitLeadingCommentsOfPosition: emitLeadingCommentsOfPosition,
+        };
+        function emitNodeWithComments(hint, node, emitCallback) {
+            if (disabled) {
+                emitCallback(hint, node);
+                return;
+            }
+            if (node) {
+                hasWrittenComment = false;
+                var emitNode = node.emitNode;
+                var emitFlags = emitNode && emitNode.flags || 0;
+                var _a = emitNode && emitNode.commentRange || node, pos = _a.pos, end = _a.end;
+                if ((pos < 0 && end < 0) || (pos === end)) {
+                    // Both pos and end are synthesized, so just emit the node without comments.
+                    emitNodeWithSynthesizedComments(hint, node, emitNode, emitFlags, emitCallback);
+                }
+                else {
+                    if (extendedDiagnostics) {
+                        ts.performance.mark("preEmitNodeWithComment");
+                    }
+                    var isEmittedNode = node.kind !== 300 /* NotEmittedStatement */;
+                    // We have to explicitly check that the node is JsxText because if the compilerOptions.jsx is "preserve" we will not do any transformation.
+                    // It is expensive to walk entire tree just to set one kind of node to have no comments.
+                    var skipLeadingComments = pos < 0 || (emitFlags & 512 /* NoLeadingComments */) !== 0 || node.kind === 10 /* JsxText */;
+                    var skipTrailingComments = end < 0 || (emitFlags & 1024 /* NoTrailingComments */) !== 0 || node.kind === 10 /* JsxText */;
+                    // Emit leading comments if the position is not synthesized and the node
+                    // has not opted out from emitting leading comments.
+                    if (!skipLeadingComments) {
+                        emitLeadingComments(pos, isEmittedNode);
+                    }
+                    // Save current container state on the stack.
+                    var savedContainerPos = containerPos;
+                    var savedContainerEnd = containerEnd;
+                    var savedDeclarationListContainerEnd = declarationListContainerEnd;
+                    if (!skipLeadingComments) {
+                        containerPos = pos;
+                    }
+                    if (!skipTrailingComments) {
+                        containerEnd = end;
+                        // To avoid invalid comment emit in a down-level binding pattern, we
+                        // keep track of the last declaration list container's end
+                        if (node.kind === 233 /* VariableDeclarationList */) {
+                            declarationListContainerEnd = end;
+                        }
+                    }
+                    if (extendedDiagnostics) {
+                        ts.performance.measure("commentTime", "preEmitNodeWithComment");
+                    }
+                    emitNodeWithSynthesizedComments(hint, node, emitNode, emitFlags, emitCallback);
+                    if (extendedDiagnostics) {
+                        ts.performance.mark("postEmitNodeWithComment");
+                    }
+                    // Restore previous container state.
+                    containerPos = savedContainerPos;
+                    containerEnd = savedContainerEnd;
+                    declarationListContainerEnd = savedDeclarationListContainerEnd;
+                    // Emit trailing comments if the position is not synthesized and the node
+                    // has not opted out from emitting leading comments and is an emitted node.
+                    if (!skipTrailingComments && isEmittedNode) {
+                        emitTrailingComments(end);
+                    }
+                    if (extendedDiagnostics) {
+                        ts.performance.measure("commentTime", "postEmitNodeWithComment");
+                    }
+                }
+            }
+        }
+        function emitNodeWithSynthesizedComments(hint, node, emitNode, emitFlags, emitCallback) {
+            var leadingComments = emitNode && emitNode.leadingComments;
+            if (ts.some(leadingComments)) {
+                if (extendedDiagnostics) {
+                    ts.performance.mark("preEmitNodeWithSynthesizedComments");
+                }
+                ts.forEach(leadingComments, emitLeadingSynthesizedComment);
+                if (extendedDiagnostics) {
+                    ts.performance.measure("commentTime", "preEmitNodeWithSynthesizedComments");
+                }
+            }
+            emitNodeWithNestedComments(hint, node, emitFlags, emitCallback);
+            var trailingComments = emitNode && emitNode.trailingComments;
+            if (ts.some(trailingComments)) {
+                if (extendedDiagnostics) {
+                    ts.performance.mark("postEmitNodeWithSynthesizedComments");
+                }
+                ts.forEach(trailingComments, emitTrailingSynthesizedComment);
+                if (extendedDiagnostics) {
+                    ts.performance.measure("commentTime", "postEmitNodeWithSynthesizedComments");
+                }
+            }
+        }
+        function emitLeadingSynthesizedComment(comment) {
+            if (comment.kind === 2 /* SingleLineCommentTrivia */) {
+                writer.writeLine();
+            }
+            writeSynthesizedComment(comment);
+            if (comment.hasTrailingNewLine || comment.kind === 2 /* SingleLineCommentTrivia */) {
+                writer.writeLine();
+            }
+            else {
+                writer.write(" ");
+            }
+        }
+        function emitTrailingSynthesizedComment(comment) {
+            if (!writer.isAtStartOfLine()) {
+                writer.write(" ");
+            }
+            writeSynthesizedComment(comment);
+            if (comment.hasTrailingNewLine) {
+                writer.writeLine();
+            }
+        }
+        function writeSynthesizedComment(comment) {
+            var text = formatSynthesizedComment(comment);
+            var lineMap = comment.kind === 3 /* MultiLineCommentTrivia */ ? ts.computeLineStarts(text) : undefined;
+            ts.writeCommentRange(text, lineMap, writer, 0, text.length, newLine);
+        }
+        function formatSynthesizedComment(comment) {
+            return comment.kind === 3 /* MultiLineCommentTrivia */
+                ? "/*" + comment.text + "*/"
+                : "//" + comment.text;
+        }
+        function emitNodeWithNestedComments(hint, node, emitFlags, emitCallback) {
+            if (emitFlags & 2048 /* NoNestedComments */) {
+                disabled = true;
+                emitCallback(hint, node);
+                disabled = false;
+            }
+            else {
+                emitCallback(hint, node);
+            }
+        }
+        function emitBodyWithDetachedComments(node, detachedRange, emitCallback) {
+            if (extendedDiagnostics) {
+                ts.performance.mark("preEmitBodyWithDetachedComments");
+            }
+            var pos = detachedRange.pos, end = detachedRange.end;
+            var emitFlags = ts.getEmitFlags(node);
+            var skipLeadingComments = pos < 0 || (emitFlags & 512 /* NoLeadingComments */) !== 0;
+            var skipTrailingComments = disabled || end < 0 || (emitFlags & 1024 /* NoTrailingComments */) !== 0;
+            if (!skipLeadingComments) {
+                emitDetachedCommentsAndUpdateCommentsInfo(detachedRange);
+            }
+            if (extendedDiagnostics) {
+                ts.performance.measure("commentTime", "preEmitBodyWithDetachedComments");
+            }
+            if (emitFlags & 2048 /* NoNestedComments */ && !disabled) {
+                disabled = true;
+                emitCallback(node);
+                disabled = false;
+            }
+            else {
+                emitCallback(node);
+            }
+            if (extendedDiagnostics) {
+                ts.performance.mark("beginEmitBodyWithDetachedCommetns");
+            }
+            if (!skipTrailingComments) {
+                emitLeadingComments(detachedRange.end, /*isEmittedNode*/ true);
+                if (hasWrittenComment && !writer.isAtStartOfLine()) {
+                    writer.writeLine();
+                }
+            }
+            if (extendedDiagnostics) {
+                ts.performance.measure("commentTime", "beginEmitBodyWithDetachedCommetns");
+            }
+        }
+        function emitLeadingComments(pos, isEmittedNode) {
+            hasWrittenComment = false;
+            if (isEmittedNode) {
+                forEachLeadingCommentToEmit(pos, emitLeadingComment);
+            }
+            else if (pos === 0) {
+                // If the node will not be emitted in JS, remove all the comments(normal, pinned and ///) associated with the node,
+                // unless it is a triple slash comment at the top of the file.
+                // For Example:
+                //      /// <reference-path ...>
+                //      declare var x;
+                //      /// <reference-path ...>
+                //      interface F {}
+                //  The first /// will NOT be removed while the second one will be removed even though both node will not be emitted
+                forEachLeadingCommentToEmit(pos, emitTripleSlashLeadingComment);
+            }
+        }
+        function emitTripleSlashLeadingComment(commentPos, commentEnd, kind, hasTrailingNewLine, rangePos) {
+            if (isTripleSlashComment(commentPos, commentEnd)) {
+                emitLeadingComment(commentPos, commentEnd, kind, hasTrailingNewLine, rangePos);
+            }
+        }
+        function shouldWriteComment(text, pos) {
+            if (printerOptions.onlyPrintJsDocStyle) {
+                return (ts.isJSDocLikeText(text, pos) || ts.isPinnedComment(text, pos));
+            }
+            return true;
+        }
+        function emitLeadingComment(commentPos, commentEnd, kind, hasTrailingNewLine, rangePos) {
+            if (!shouldWriteComment(currentText, commentPos))
+                return;
+            if (!hasWrittenComment) {
+                ts.emitNewLineBeforeLeadingCommentOfPosition(currentLineMap, writer, rangePos, commentPos);
+                hasWrittenComment = true;
+            }
+            // Leading comments are emitted at /*leading comment1 */space/*leading comment*/space
+            if (emitPos)
+                emitPos(commentPos);
+            ts.writeCommentRange(currentText, currentLineMap, writer, commentPos, commentEnd, newLine);
+            if (emitPos)
+                emitPos(commentEnd);
+            if (hasTrailingNewLine) {
+                writer.writeLine();
+            }
+            else if (kind === 3 /* MultiLineCommentTrivia */) {
+                writer.write(" ");
+            }
+        }
+        function emitLeadingCommentsOfPosition(pos) {
+            if (disabled || pos === -1) {
+                return;
+            }
+            emitLeadingComments(pos, /*isEmittedNode*/ true);
+        }
+        function emitTrailingComments(pos) {
+            forEachTrailingCommentToEmit(pos, emitTrailingComment);
+        }
+        function emitTrailingComment(commentPos, commentEnd, _kind, hasTrailingNewLine) {
+            if (!shouldWriteComment(currentText, commentPos))
+                return;
+            // trailing comments are emitted at space/*trailing comment1 */space/*trailing comment2*/
+            if (!writer.isAtStartOfLine()) {
+                writer.write(" ");
+            }
+            if (emitPos)
+                emitPos(commentPos);
+            ts.writeCommentRange(currentText, currentLineMap, writer, commentPos, commentEnd, newLine);
+            if (emitPos)
+                emitPos(commentEnd);
+            if (hasTrailingNewLine) {
+                writer.writeLine();
+            }
+        }
+        function emitTrailingCommentsOfPosition(pos, prefixSpace) {
+            if (disabled) {
+                return;
+            }
+            if (extendedDiagnostics) {
+                ts.performance.mark("beforeEmitTrailingCommentsOfPosition");
+            }
+            forEachTrailingCommentToEmit(pos, prefixSpace ? emitTrailingComment : emitTrailingCommentOfPosition);
+            if (extendedDiagnostics) {
+                ts.performance.measure("commentTime", "beforeEmitTrailingCommentsOfPosition");
+            }
+        }
+        function emitTrailingCommentOfPosition(commentPos, commentEnd, _kind, hasTrailingNewLine) {
+            // trailing comments of a position are emitted at /*trailing comment1 */space/*trailing comment*/space
+            if (emitPos)
+                emitPos(commentPos);
+            ts.writeCommentRange(currentText, currentLineMap, writer, commentPos, commentEnd, newLine);
+            if (emitPos)
+                emitPos(commentEnd);
+            if (hasTrailingNewLine) {
+                writer.writeLine();
+            }
+            else {
+                writer.write(" ");
+            }
+        }
+        function forEachLeadingCommentToEmit(pos, cb) {
+            // Emit the leading comments only if the container's pos doesn't match because the container should take care of emitting these comments
+            if (containerPos === -1 || pos !== containerPos) {
+                if (hasDetachedComments(pos)) {
+                    forEachLeadingCommentWithoutDetachedComments(cb);
+                }
+                else {
+                    ts.forEachLeadingCommentRange(currentText, pos, cb, /*state*/ pos);
+                }
+            }
+        }
+        function forEachTrailingCommentToEmit(end, cb) {
+            // Emit the trailing comments only if the container's end doesn't match because the container should take care of emitting these comments
+            if (containerEnd === -1 || (end !== containerEnd && end !== declarationListContainerEnd)) {
+                ts.forEachTrailingCommentRange(currentText, end, cb);
+            }
+        }
+        function reset() {
+            currentSourceFile = undefined;
+            currentText = undefined;
+            currentLineMap = undefined;
+            detachedCommentsInfo = undefined;
+        }
+        function setWriter(output) {
+            writer = output;
+        }
+        function setSourceFile(sourceFile) {
+            currentSourceFile = sourceFile;
+            currentText = currentSourceFile.text;
+            currentLineMap = ts.getLineStarts(currentSourceFile);
+            detachedCommentsInfo = undefined;
+        }
+        function hasDetachedComments(pos) {
+            return detachedCommentsInfo !== undefined && ts.last(detachedCommentsInfo).nodePos === pos;
+        }
+        function forEachLeadingCommentWithoutDetachedComments(cb) {
+            // get the leading comments from detachedPos
+            var pos = ts.last(detachedCommentsInfo).detachedCommentEndPos;
+            if (detachedCommentsInfo.length - 1) {
+                detachedCommentsInfo.pop();
+            }
+            else {
+                detachedCommentsInfo = undefined;
+            }
+            ts.forEachLeadingCommentRange(currentText, pos, cb, /*state*/ pos);
+        }
+        function emitDetachedCommentsAndUpdateCommentsInfo(range) {
+            var currentDetachedCommentInfo = ts.emitDetachedComments(currentText, currentLineMap, writer, writeComment, range, newLine, disabled);
+            if (currentDetachedCommentInfo) {
+                if (detachedCommentsInfo) {
+                    detachedCommentsInfo.push(currentDetachedCommentInfo);
+                }
+                else {
+                    detachedCommentsInfo = [currentDetachedCommentInfo];
+                }
+            }
+        }
+        function writeComment(text, lineMap, writer, commentPos, commentEnd, newLine) {
+            if (!shouldWriteComment(currentText, commentPos))
+                return;
+            if (emitPos)
+                emitPos(commentPos);
+            ts.writeCommentRange(text, lineMap, writer, commentPos, commentEnd, newLine);
+            if (emitPos)
+                emitPos(commentEnd);
+        }
+        /**
+         * Determine if the given comment is a triple-slash
+         *
+         * @return true if the comment is a triple-slash comment else false
+         */
+        function isTripleSlashComment(commentPos, commentEnd) {
+            return ts.isRecognizedTripleSlashComment(currentText, commentPos, commentEnd);
+        }
+    }
+    ts.createCommentWriter = createCommentWriter;
+})(ts || (ts = {}));
+var ts;
+(function (ts) {
+    var infoExtension = ".tsbundleinfo";
+    var brackets = createBracketsMap();
+    /*@internal*/
+    /**
+     * Iterates over the source files that are expected to have an emit output.
+     *
+     * @param host An EmitHost.
+     * @param action The action to execute.
+     * @param sourceFilesOrTargetSourceFile
+     *   If an array, the full list of source files to emit.
+     *   Else, calls `getSourceFilesToEmit` with the (optional) target source file to determine the list of source files to emit.
+     */
+    function forEachEmittedFile(host, action, sourceFilesOrTargetSourceFile, emitOnlyDtsFiles) {
+        if (emitOnlyDtsFiles === void 0) { emitOnlyDtsFiles = false; }
+        var sourceFiles = ts.isArray(sourceFilesOrTargetSourceFile) ? sourceFilesOrTargetSourceFile : ts.getSourceFilesToEmit(host, sourceFilesOrTargetSourceFile);
+        var options = host.getCompilerOptions();
+        if (options.outFile || options.out) {
+            if (sourceFiles.length) {
+                var bundle = ts.createBundle(sourceFiles, host.getPrependNodes());
+                var result = action(getOutputPathsFor(bundle, host, emitOnlyDtsFiles), bundle);
+                if (result) {
+                    return result;
+                }
+            }
+        }
+        else {
+            for (var _a = 0, sourceFiles_1 = sourceFiles; _a < sourceFiles_1.length; _a++) {
+                var sourceFile = sourceFiles_1[_a];
+                var result = action(getOutputPathsFor(sourceFile, host, emitOnlyDtsFiles), sourceFile);
+                if (result) {
+                    return result;
+                }
+            }
+        }
+    }
+    ts.forEachEmittedFile = forEachEmittedFile;
+    /*@internal*/
+    function getOutputPathsFor(sourceFile, host, forceDtsPaths) {
+        var options = host.getCompilerOptions();
+        if (sourceFile.kind === 275 /* Bundle */) {
+            var jsFilePath = options.outFile || options.out;
+            var sourceMapFilePath = getSourceMapFilePath(jsFilePath, options);
+            var declarationFilePath = (forceDtsPaths || options.declaration) ? ts.removeFileExtension(jsFilePath) + ".d.ts" /* Dts */ : undefined;
+            var declarationMapPath = ts.getAreDeclarationMapsEnabled(options) ? declarationFilePath + ".map" : undefined;
+            var bundleInfoPath = options.references && jsFilePath ? (ts.removeFileExtension(jsFilePath) + infoExtension) : undefined;
+            return { jsFilePath: jsFilePath, sourceMapFilePath: sourceMapFilePath, declarationFilePath: declarationFilePath, declarationMapPath: declarationMapPath, bundleInfoPath: bundleInfoPath };
+        }
+        else {
+            var jsFilePath = ts.getOwnEmitOutputFilePath(sourceFile, host, getOutputExtension(sourceFile, options));
+            var sourceMapFilePath = ts.isJsonSourceFile(sourceFile) ? undefined : getSourceMapFilePath(jsFilePath, options);
+            // For legacy reasons (ie, we have baselines capturing the behavior), js files don't report a .d.ts output path - this would only matter if `declaration` and `allowJs` were both on, which is currently an error
+            var isJs = ts.isSourceFileJavaScript(sourceFile);
+            var declarationFilePath = ((forceDtsPaths || options.declaration) && !isJs) ? ts.getDeclarationEmitOutputFilePath(sourceFile, host) : undefined;
+            var declarationMapPath = ts.getAreDeclarationMapsEnabled(options) ? declarationFilePath + ".map" : undefined;
+            return { jsFilePath: jsFilePath, sourceMapFilePath: sourceMapFilePath, declarationFilePath: declarationFilePath, declarationMapPath: declarationMapPath, bundleInfoPath: undefined };
+        }
+    }
+    ts.getOutputPathsFor = getOutputPathsFor;
+    function getSourceMapFilePath(jsFilePath, options) {
+        return (options.sourceMap && !options.inlineSourceMap) ? jsFilePath + ".map" : undefined;
+    }
+    function createDefaultBundleInfo() {
+        return {
+            originalOffset: -1,
+            totalLength: -1
+        };
+    }
+    // JavaScript files are always LanguageVariant.JSX, as JSX syntax is allowed in .js files also.
+    // So for JavaScript files, '.jsx' is only emitted if the input was '.jsx', and JsxEmit.Preserve.
+    // For TypeScript, the only time to emit with a '.jsx' extension, is on JSX input, and JsxEmit.Preserve
+    /* @internal */
+    function getOutputExtension(sourceFile, options) {
+        if (ts.isJsonSourceFile(sourceFile)) {
+            return ".json" /* Json */;
+        }
+        if (options.jsx === 1 /* Preserve */) {
+            if (ts.isSourceFileJavaScript(sourceFile)) {
+                if (ts.fileExtensionIs(sourceFile.fileName, ".jsx" /* Jsx */)) {
+                    return ".jsx" /* Jsx */;
+                }
+            }
+            else if (sourceFile.languageVariant === 1 /* JSX */) {
+                // TypeScript source file preserving JSX syntax
+                return ".jsx" /* Jsx */;
+            }
+        }
+        return ".js" /* Js */;
+    }
+    ts.getOutputExtension = getOutputExtension;
+    /*@internal*/
+    // targetSourceFile is when users only want one file in entire project to be emitted. This is used in compileOnSave feature
+    function emitFiles(resolver, host, targetSourceFile, emitOnlyDtsFiles, transformers, declarationTransformers) {
+        var compilerOptions = host.getCompilerOptions();
+        var sourceMapDataList = (compilerOptions.sourceMap || compilerOptions.inlineSourceMap || ts.getAreDeclarationMapsEnabled(compilerOptions)) ? [] : undefined;
+        var emittedFilesList = compilerOptions.listEmittedFiles ? [] : undefined;
+        var emitterDiagnostics = ts.createDiagnosticCollection();
+        var newLine = host.getNewLine();
+        var writer = ts.createTextWriter(newLine);
+        var sourceMap = ts.createSourceMapWriter(host, writer);
+        var declarationSourceMap = ts.createSourceMapWriter(host, writer, {
+            sourceMap: compilerOptions.declarationMap,
+            sourceRoot: compilerOptions.sourceRoot,
+            mapRoot: compilerOptions.mapRoot,
+            extendedDiagnostics: compilerOptions.extendedDiagnostics,
+        });
+        var bundleInfo = createDefaultBundleInfo();
+        var emitSkipped = false;
+        // Emit each output file
+        ts.performance.mark("beforePrint");
+        forEachEmittedFile(host, emitSourceFileOrBundle, ts.getSourceFilesToEmit(host, targetSourceFile), emitOnlyDtsFiles);
+        ts.performance.measure("printTime", "beforePrint");
+        return {
+            emitSkipped: emitSkipped,
+            diagnostics: emitterDiagnostics.getDiagnostics(),
+            emittedFiles: emittedFilesList,
+            sourceMaps: sourceMapDataList,
+        };
+        function emitSourceFileOrBundle(_a, sourceFileOrBundle) {
+            var jsFilePath = _a.jsFilePath, sourceMapFilePath = _a.sourceMapFilePath, declarationFilePath = _a.declarationFilePath, declarationMapPath = _a.declarationMapPath, bundleInfoPath = _a.bundleInfoPath;
+            emitJsFileOrBundle(sourceFileOrBundle, jsFilePath, sourceMapFilePath, bundleInfoPath);
+            emitDeclarationFileOrBundle(sourceFileOrBundle, declarationFilePath, declarationMapPath);
+            if (!emitSkipped && emittedFilesList) {
+                if (!emitOnlyDtsFiles) {
+                    emittedFilesList.push(jsFilePath);
+                }
+                if (sourceMapFilePath) {
+                    emittedFilesList.push(sourceMapFilePath);
+                }
+                if (declarationFilePath) {
+                    emittedFilesList.push(declarationFilePath);
+                }
+                if (bundleInfoPath) {
+                    emittedFilesList.push(bundleInfoPath);
+                }
+            }
+        }
+        function emitJsFileOrBundle(sourceFileOrBundle, jsFilePath, sourceMapFilePath, bundleInfoPath) {
+            // Make sure not to write js file and source map file if any of them cannot be written
+            if (host.isEmitBlocked(jsFilePath) || compilerOptions.noEmit || compilerOptions.emitDeclarationOnly) {
+                emitSkipped = true;
+                return;
+            }
+            if (emitOnlyDtsFiles) {
+                return;
+            }
+            // Transform the source files
+            var transform = ts.transformNodes(resolver, host, compilerOptions, [sourceFileOrBundle], transformers, /*allowDtsFiles*/ false);
+            // Create a printer to print the nodes
+            var printer = createPrinter(__assign({}, compilerOptions, { noEmitHelpers: compilerOptions.noEmitHelpers }), {
+                // resolver hooks
+                hasGlobalName: resolver.hasGlobalName,
+                // transform hooks
+                onEmitNode: transform.emitNodeWithNotification,
+                substituteNode: transform.substituteNode,
+                // sourcemap hooks
+                onEmitSourceMapOfNode: sourceMap.emitNodeWithSourceMap,
+                onEmitSourceMapOfToken: sourceMap.emitTokenWithSourceMap,
+                onEmitSourceMapOfPosition: sourceMap.emitPos,
+                // emitter hooks
+                onSetSourceFile: setSourceFile,
+            });
+            ts.Debug.assert(transform.transformed.length === 1, "Should only see one output from the transform");
+            printSourceFileOrBundle(jsFilePath, sourceMapFilePath, transform.transformed[0], bundleInfoPath, printer, sourceMap);
+            // Clean up emit nodes on parse tree
+            transform.dispose();
+        }
+        function emitDeclarationFileOrBundle(sourceFileOrBundle, declarationFilePath, declarationMapPath) {
+            if (!(declarationFilePath && !ts.isInJavaScriptFile(sourceFileOrBundle))) {
+                return;
+            }
+            var sourceFiles = ts.isSourceFile(sourceFileOrBundle) ? [sourceFileOrBundle] : sourceFileOrBundle.sourceFiles;
+            // Setup and perform the transformation to retrieve declarations from the input files
+            var nonJsFiles = ts.filter(sourceFiles, ts.isSourceFileNotJavaScript);
+            var inputListOrBundle = (compilerOptions.outFile || compilerOptions.out) ? [ts.createBundle(nonJsFiles, !ts.isSourceFile(sourceFileOrBundle) ? sourceFileOrBundle.prepends : undefined)] : nonJsFiles;
+            var declarationTransform = ts.transformNodes(resolver, host, compilerOptions, inputListOrBundle, ts.concatenate([ts.transformDeclarations], declarationTransformers), /*allowDtsFiles*/ false);
+            if (ts.length(declarationTransform.diagnostics)) {
+                for (var _a = 0, _b = declarationTransform.diagnostics; _a < _b.length; _a++) {
+                    var diagnostic = _b[_a];
+                    emitterDiagnostics.add(diagnostic);
+                }
+            }
+            var declarationPrinter = createPrinter(__assign({}, compilerOptions, { onlyPrintJsDocStyle: true, noEmitHelpers: true }), {
+                // resolver hooks
+                hasGlobalName: resolver.hasGlobalName,
+                // sourcemap hooks
+                onEmitSourceMapOfNode: declarationSourceMap.emitNodeWithSourceMap,
+                onEmitSourceMapOfToken: declarationSourceMap.emitTokenWithSourceMap,
+                onEmitSourceMapOfPosition: declarationSourceMap.emitPos,
+                onSetSourceFile: setSourceFileForDeclarationSourceMaps,
+                // transform hooks
+                onEmitNode: declarationTransform.emitNodeWithNotification,
+                substituteNode: declarationTransform.substituteNode,
+            });
+            var declBlocked = (!!declarationTransform.diagnostics && !!declarationTransform.diagnostics.length) || !!host.isEmitBlocked(declarationFilePath) || !!compilerOptions.noEmit;
+            emitSkipped = emitSkipped || declBlocked;
+            if (!declBlocked || emitOnlyDtsFiles) {
+                ts.Debug.assert(declarationTransform.transformed.length === 1, "Should only see one output from the decl transform");
+                printSourceFileOrBundle(declarationFilePath, declarationMapPath, declarationTransform.transformed[0], /* bundleInfopath*/ undefined, declarationPrinter, declarationSourceMap);
+            }
+            declarationTransform.dispose();
+        }
+        function printSourceFileOrBundle(jsFilePath, sourceMapFilePath, sourceFileOrBundle, bundleInfoPath, printer, mapRecorder) {
+            var bundle = sourceFileOrBundle.kind === 275 /* Bundle */ ? sourceFileOrBundle : undefined;
+            var sourceFile = sourceFileOrBundle.kind === 274 /* SourceFile */ ? sourceFileOrBundle : undefined;
+            var sourceFiles = bundle ? bundle.sourceFiles : [sourceFile];
+            mapRecorder.initialize(jsFilePath, sourceMapFilePath || "", sourceFileOrBundle, sourceMapDataList);
+            if (bundle) {
+                printer.writeBundle(bundle, writer, bundleInfo);
+            }
+            else {
+                printer.writeFile(sourceFile, writer);
+            }
+            writer.writeLine();
+            var sourceMappingURL = mapRecorder.getSourceMappingURL();
+            if (sourceMappingURL) {
+                writer.write("//# " + "sourceMappingURL" + "=" + sourceMappingURL); // Sometimes tools can sometimes see this line as a source mapping url comment
+            }
+            // Write the source map
+            if (sourceMapFilePath) {
+                ts.writeFile(host, emitterDiagnostics, sourceMapFilePath, mapRecorder.getText(), /*writeByteOrderMark*/ false, sourceFiles);
+            }
+            // Write the output file
+            ts.writeFile(host, emitterDiagnostics, jsFilePath, writer.getText(), !!compilerOptions.emitBOM, sourceFiles);
+            // Write bundled offset information if applicable
+            if (bundleInfoPath) {
+                bundleInfo.totalLength = writer.getTextPos();
+                ts.writeFile(host, emitterDiagnostics, bundleInfoPath, JSON.stringify(bundleInfo, undefined, 2), /*writeByteOrderMark*/ false);
+            }
+            // Reset state
+            mapRecorder.reset();
+            writer.clear();
+            bundleInfo = createDefaultBundleInfo();
+        }
+        function setSourceFile(node) {
+            sourceMap.setSourceFile(node);
+        }
+        function setSourceFileForDeclarationSourceMaps(node) {
+            declarationSourceMap.setSourceFile(node);
+        }
+    }
+    ts.emitFiles = emitFiles;
+    var PipelinePhase;
+    (function (PipelinePhase) {
+        PipelinePhase[PipelinePhase["Notification"] = 0] = "Notification";
+        PipelinePhase[PipelinePhase["Comments"] = 1] = "Comments";
+        PipelinePhase[PipelinePhase["SourceMaps"] = 2] = "SourceMaps";
+        PipelinePhase[PipelinePhase["Emit"] = 3] = "Emit";
+    })(PipelinePhase || (PipelinePhase = {}));
+    function createPrinter(printerOptions, handlers) {
+        if (printerOptions === void 0) { printerOptions = {}; }
+        if (handlers === void 0) { handlers = {}; }
+        var hasGlobalName = handlers.hasGlobalName, onEmitSourceMapOfNode = handlers.onEmitSourceMapOfNode, onEmitSourceMapOfToken = handlers.onEmitSourceMapOfToken, onEmitSourceMapOfPosition = handlers.onEmitSourceMapOfPosition, onEmitNode = handlers.onEmitNode, onSetSourceFile = handlers.onSetSourceFile, substituteNode = handlers.substituteNode, onBeforeEmitNodeArray = handlers.onBeforeEmitNodeArray, onAfterEmitNodeArray = handlers.onAfterEmitNodeArray, onBeforeEmitToken = handlers.onBeforeEmitToken, onAfterEmitToken = handlers.onAfterEmitToken;
+        var newLine = ts.getNewLineCharacter(printerOptions);
+        var comments = ts.createCommentWriter(printerOptions, onEmitSourceMapOfPosition);
+        var emitNodeWithComments = comments.emitNodeWithComments, emitBodyWithDetachedComments = comments.emitBodyWithDetachedComments, emitTrailingCommentsOfPosition = comments.emitTrailingCommentsOfPosition, emitLeadingCommentsOfPosition = comments.emitLeadingCommentsOfPosition;
+        var currentSourceFile;
+        var nodeIdToGeneratedName; // Map of generated names for specific nodes.
+        var autoGeneratedIdToGeneratedName; // Map of generated names for temp and loop variables.
+        var generatedNames; // Set of names generated by the NameGenerator.
+        var tempFlagsStack; // Stack of enclosing name generation scopes.
+        var tempFlags; // TempFlags for the current name generation scope.
+        var reservedNamesStack; // Stack of TempFlags reserved in enclosing name generation scopes.
+        var reservedNames; // TempFlags to reserve in nested name generation scopes.
+        var writer;
+        var ownWriter;
+        var write = writeBase;
+        var commitPendingSemicolon = ts.noop;
+        var writeSemicolon = writeSemicolonInternal;
+        var pendingSemicolon = false;
+        if (printerOptions.omitTrailingSemicolon) {
+            commitPendingSemicolon = commitPendingSemicolonInternal;
+            writeSemicolon = deferWriteSemicolon;
+        }
+        var syntheticParent = { pos: -1, end: -1 };
+        var moduleKind = ts.getEmitModuleKind(printerOptions);
+        var bundledHelpers = ts.createMap();
+        var isOwnFileEmit;
+        reset();
+        return {
+            // public API
+            printNode: printNode,
+            printList: printList,
+            printFile: printFile,
+            printBundle: printBundle,
+            // internal API
+            writeNode: writeNode,
+            writeList: writeList,
+            writeFile: writeFile,
+            writeBundle: writeBundle
+        };
+        function printNode(hint, node, sourceFile) {
+            switch (hint) {
+                case 0 /* SourceFile */:
+                    ts.Debug.assert(ts.isSourceFile(node), "Expected a SourceFile node.");
+                    break;
+                case 2 /* IdentifierName */:
+                    ts.Debug.assert(ts.isIdentifier(node), "Expected an Identifier node.");
+                    break;
+                case 1 /* Expression */:
+                    ts.Debug.assert(ts.isExpression(node), "Expected an Expression node.");
+                    break;
+            }
+            switch (node.kind) {
+                case 274 /* SourceFile */: return printFile(node);
+                case 275 /* Bundle */: return printBundle(node);
+                case 276 /* UnparsedSource */: return printUnparsedSource(node);
+            }
+            writeNode(hint, node, sourceFile, beginPrint());
+            return endPrint();
+        }
+        function printList(format, nodes, sourceFile) {
+            writeList(format, nodes, sourceFile, beginPrint());
+            return endPrint();
+        }
+        function printBundle(bundle) {
+            writeBundle(bundle, beginPrint());
+            return endPrint();
+        }
+        function printFile(sourceFile) {
+            writeFile(sourceFile, beginPrint());
+            return endPrint();
+        }
+        function printUnparsedSource(unparsed) {
+            writeUnparsedSource(unparsed, beginPrint());
+            return endPrint();
+        }
+        function writeNode(hint, node, sourceFile, output) {
+            var previousWriter = writer;
+            setWriter(output);
+            print(hint, node, sourceFile);
+            reset();
+            writer = previousWriter;
+        }
+        function writeList(format, nodes, sourceFile, output) {
+            var previousWriter = writer;
+            setWriter(output);
+            if (sourceFile) {
+                setSourceFile(sourceFile);
+            }
+            emitList(syntheticParent, nodes, format);
+            reset();
+            writer = previousWriter;
+        }
+        function writeBundle(bundle, output, bundleInfo) {
+            isOwnFileEmit = false;
+            var previousWriter = writer;
+            setWriter(output);
+            emitShebangIfNeeded(bundle);
+            emitPrologueDirectivesIfNeeded(bundle);
+            emitHelpers(bundle);
+            emitSyntheticTripleSlashReferencesIfNeeded(bundle);
+            for (var _a = 0, _b = bundle.prepends; _a < _b.length; _a++) {
+                var prepend = _b[_a];
+                print(4 /* Unspecified */, prepend, /*sourceFile*/ undefined);
+                writeLine();
+            }
+            if (bundleInfo) {
+                bundleInfo.originalOffset = writer.getTextPos();
+            }
+            for (var _c = 0, _d = bundle.sourceFiles; _c < _d.length; _c++) {
+                var sourceFile = _d[_c];
+                print(0 /* SourceFile */, sourceFile, sourceFile);
+            }
+            reset();
+            writer = previousWriter;
+        }
+        function writeUnparsedSource(unparsed, output) {
+            var previousWriter = writer;
+            setWriter(output);
+            print(4 /* Unspecified */, unparsed, /*sourceFile*/ undefined);
+            reset();
+            writer = previousWriter;
+        }
+        function writeFile(sourceFile, output) {
+            isOwnFileEmit = true;
+            var previousWriter = writer;
+            setWriter(output);
+            emitShebangIfNeeded(sourceFile);
+            emitPrologueDirectivesIfNeeded(sourceFile);
+            print(0 /* SourceFile */, sourceFile, sourceFile);
+            reset();
+            writer = previousWriter;
+        }
+        function beginPrint() {
+            return ownWriter || (ownWriter = ts.createTextWriter(newLine));
+        }
+        function endPrint() {
+            var text = ownWriter.getText();
+            ownWriter.clear();
+            return text;
+        }
+        function print(hint, node, sourceFile) {
+            if (sourceFile) {
+                setSourceFile(sourceFile);
+            }
+            var pipelinePhase = getPipelinePhase(0 /* Notification */, hint);
+            pipelinePhase(hint, node);
+        }
+        function setSourceFile(sourceFile) {
+            currentSourceFile = sourceFile;
+            comments.setSourceFile(sourceFile);
+            if (onSetSourceFile) {
+                onSetSourceFile(sourceFile);
+            }
+        }
+        function setWriter(output) {
+            writer = output; // TODO: GH#18217
+            comments.setWriter(output);
+        }
+        function reset() {
+            nodeIdToGeneratedName = [];
+            autoGeneratedIdToGeneratedName = [];
+            generatedNames = ts.createMap();
+            tempFlagsStack = [];
+            tempFlags = 0 /* Auto */;
+            reservedNamesStack = [];
+            comments.reset();
+            setWriter(/*output*/ undefined);
+        }
+        function emit(node) {
+            if (!node)
+                return;
+            var pipelinePhase = getPipelinePhase(0 /* Notification */, 4 /* Unspecified */);
+            pipelinePhase(4 /* Unspecified */, node);
+        }
+        function emitIdentifierName(node) {
+            if (!node)
+                return;
+            var pipelinePhase = getPipelinePhase(0 /* Notification */, 2 /* IdentifierName */);
+            pipelinePhase(2 /* IdentifierName */, node);
+        }
+        function emitExpression(node) {
+            if (!node)
+                return;
+            var pipelinePhase = getPipelinePhase(0 /* Notification */, 1 /* Expression */);
+            pipelinePhase(1 /* Expression */, node);
+        }
+        function getPipelinePhase(phase, hint) {
+            switch (phase) {
+                case 0 /* Notification */:
+                    if (onEmitNode) {
+                        return pipelineEmitWithNotification;
+                    }
+                // falls through
+                case 1 /* Comments */:
+                    if (emitNodeWithComments && hint !== 0 /* SourceFile */) {
+                        return pipelineEmitWithComments;
+                    }
+                    return pipelineEmitWithoutComments;
+                case 2 /* SourceMaps */:
+                    if (onEmitSourceMapOfNode && hint !== 0 /* SourceFile */ && hint !== 2 /* IdentifierName */) {
+                        return pipelineEmitWithSourceMap;
+                    }
+                // falls through
+                case 3 /* Emit */:
+                    return pipelineEmitWithHint;
+                default:
+                    return ts.Debug.assertNever(phase, "Unexpected value for PipelinePhase: " + phase);
+            }
+        }
+        function getNextPipelinePhase(currentPhase, hint) {
+            return getPipelinePhase(currentPhase + 1, hint);
+        }
+        function pipelineEmitWithNotification(hint, node) {
+            ts.Debug.assertDefined(onEmitNode)(hint, node, getNextPipelinePhase(0 /* Notification */, hint));
+        }
+        function pipelineEmitWithComments(hint, node) {
+            ts.Debug.assertDefined(emitNodeWithComments);
+            ts.Debug.assert(hint !== 0 /* SourceFile */);
+            emitNodeWithComments(hint, trySubstituteNode(hint, node), getNextPipelinePhase(1 /* Comments */, hint));
+        }
+        function pipelineEmitWithoutComments(hint, node) {
+            var pipelinePhase = getNextPipelinePhase(1 /* Comments */, hint);
+            pipelinePhase(hint, trySubstituteNode(hint, node));
+        }
+        function pipelineEmitWithSourceMap(hint, node) {
+            ts.Debug.assert(hint !== 0 /* SourceFile */ && hint !== 2 /* IdentifierName */);
+            ts.Debug.assertDefined(onEmitSourceMapOfNode)(hint, node, pipelineEmitWithHint);
+        }
+        function pipelineEmitWithHint(hint, node) {
+            if (hint === 0 /* SourceFile */)
+                return emitSourceFile(ts.cast(node, ts.isSourceFile));
+            if (hint === 2 /* IdentifierName */)
+                return emitIdentifier(ts.cast(node, ts.isIdentifier));
+            if (hint === 3 /* MappedTypeParameter */)
+                return emitMappedTypeParameter(ts.cast(node, ts.isTypeParameterDeclaration));
+            if (hint === 4 /* Unspecified */) {
+                if (ts.isKeyword(node.kind))
+                    return writeTokenNode(node, writeKeyword);
+                switch (node.kind) {
+                    // Pseudo-literals
+                    case 14 /* TemplateHead */:
+                    case 15 /* TemplateMiddle */:
+                    case 16 /* TemplateTail */:
+                        return emitLiteral(node);
+                    case 276 /* UnparsedSource */:
+                        return emitUnparsedSource(node);
+                    // Identifiers
+                    case 71 /* Identifier */:
+                        return emitIdentifier(node);
+                    // Parse tree nodes
+                    // Names
+                    case 146 /* QualifiedName */:
+                        return emitQualifiedName(node);
+                    case 147 /* ComputedPropertyName */:
+                        return emitComputedPropertyName(node);
+                    // Signature elements
+                    case 148 /* TypeParameter */:
+                        return emitTypeParameter(node);
+                    case 149 /* Parameter */:
+                        return emitParameter(node);
+                    case 150 /* Decorator */:
+                        return emitDecorator(node);
+                    // Type members
+                    case 151 /* PropertySignature */:
+                        return emitPropertySignature(node);
+                    case 152 /* PropertyDeclaration */:
+                        return emitPropertyDeclaration(node);
+                    case 153 /* MethodSignature */:
+                        return emitMethodSignature(node);
+                    case 154 /* MethodDeclaration */:
+                        return emitMethodDeclaration(node);
+                    case 155 /* Constructor */:
+                        return emitConstructor(node);
+                    case 156 /* GetAccessor */:
+                    case 157 /* SetAccessor */:
+                        return emitAccessorDeclaration(node);
+                    case 158 /* CallSignature */:
+                        return emitCallSignature(node);
+                    case 159 /* ConstructSignature */:
+                        return emitConstructSignature(node);
+                    case 160 /* IndexSignature */:
+                        return emitIndexSignature(node);
+                    // Types
+                    case 161 /* TypePredicate */:
+                        return emitTypePredicate(node);
+                    case 162 /* TypeReference */:
+                        return emitTypeReference(node);
+                    case 163 /* FunctionType */:
+                        return emitFunctionType(node);
+                    case 284 /* JSDocFunctionType */:
+                        return emitJSDocFunctionType(node);
+                    case 164 /* ConstructorType */:
+                        return emitConstructorType(node);
+                    case 165 /* TypeQuery */:
+                        return emitTypeQuery(node);
+                    case 166 /* TypeLiteral */:
+                        return emitTypeLiteral(node);
+                    case 167 /* ArrayType */:
+                        return emitArrayType(node);
+                    case 168 /* TupleType */:
+                        return emitTupleType(node);
+                    case 169 /* UnionType */:
+                        return emitUnionType(node);
+                    case 170 /* IntersectionType */:
+                        return emitIntersectionType(node);
+                    case 171 /* ConditionalType */:
+                        return emitConditionalType(node);
+                    case 172 /* InferType */:
+                        return emitInferType(node);
+                    case 173 /* ParenthesizedType */:
+                        return emitParenthesizedType(node);
+                    case 207 /* ExpressionWithTypeArguments */:
+                        return emitExpressionWithTypeArguments(node);
+                    case 174 /* ThisType */:
+                        return emitThisType();
+                    case 175 /* TypeOperator */:
+                        return emitTypeOperator(node);
+                    case 176 /* IndexedAccessType */:
+                        return emitIndexedAccessType(node);
+                    case 177 /* MappedType */:
+                        return emitMappedType(node);
+                    case 178 /* LiteralType */:
+                        return emitLiteralType(node);
+                    case 179 /* ImportType */:
+                        return emitImportTypeNode(node);
+                    case 279 /* JSDocAllType */:
+                        write("*");
+                        return;
+                    case 280 /* JSDocUnknownType */:
+                        write("?");
+                        return;
+                    case 281 /* JSDocNullableType */:
+                        return emitJSDocNullableType(node);
+                    case 282 /* JSDocNonNullableType */:
+                        return emitJSDocNonNullableType(node);
+                    case 283 /* JSDocOptionalType */:
+                        return emitJSDocOptionalType(node);
+                    case 285 /* JSDocVariadicType */:
+                        return emitJSDocVariadicType(node);
+                    // Binding patterns
+                    case 180 /* ObjectBindingPattern */:
+                        return emitObjectBindingPattern(node);
+                    case 181 /* ArrayBindingPattern */:
+                        return emitArrayBindingPattern(node);
+                    case 182 /* BindingElement */:
+                        return emitBindingElement(node);
+                    // Misc
+                    case 211 /* TemplateSpan */:
+                        return emitTemplateSpan(node);
+                    case 212 /* SemicolonClassElement */:
+                        return emitSemicolonClassElement();
+                    // Statements
+                    case 213 /* Block */:
+                        return emitBlock(node);
+                    case 214 /* VariableStatement */:
+                        return emitVariableStatement(node);
+                    case 215 /* EmptyStatement */:
+                        return emitEmptyStatement();
+                    case 216 /* ExpressionStatement */:
+                        return emitExpressionStatement(node);
+                    case 217 /* IfStatement */:
+                        return emitIfStatement(node);
+                    case 218 /* DoStatement */:
+                        return emitDoStatement(node);
+                    case 219 /* WhileStatement */:
+                        return emitWhileStatement(node);
+                    case 220 /* ForStatement */:
+                        return emitForStatement(node);
+                    case 221 /* ForInStatement */:
+                        return emitForInStatement(node);
+                    case 222 /* ForOfStatement */:
+                        return emitForOfStatement(node);
+                    case 223 /* ContinueStatement */:
+                        return emitContinueStatement(node);
+                    case 224 /* BreakStatement */:
+                        return emitBreakStatement(node);
+                    case 225 /* ReturnStatement */:
+                        return emitReturnStatement(node);
+                    case 226 /* WithStatement */:
+                        return emitWithStatement(node);
+                    case 227 /* SwitchStatement */:
+                        return emitSwitchStatement(node);
+                    case 228 /* LabeledStatement */:
+                        return emitLabeledStatement(node);
+                    case 229 /* ThrowStatement */:
+                        return emitThrowStatement(node);
+                    case 230 /* TryStatement */:
+                        return emitTryStatement(node);
+                    case 231 /* DebuggerStatement */:
+                        return emitDebuggerStatement(node);
+                    // Declarations
+                    case 232 /* VariableDeclaration */:
+                        return emitVariableDeclaration(node);
+                    case 233 /* VariableDeclarationList */:
+                        return emitVariableDeclarationList(node);
+                    case 234 /* FunctionDeclaration */:
+                        return emitFunctionDeclaration(node);
+                    case 235 /* ClassDeclaration */:
+                        return emitClassDeclaration(node);
+                    case 236 /* InterfaceDeclaration */:
+                        return emitInterfaceDeclaration(node);
+                    case 237 /* TypeAliasDeclaration */:
+                        return emitTypeAliasDeclaration(node);
+                    case 238 /* EnumDeclaration */:
+                        return emitEnumDeclaration(node);
+                    case 239 /* ModuleDeclaration */:
+                        return emitModuleDeclaration(node);
+                    case 240 /* ModuleBlock */:
+                        return emitModuleBlock(node);
+                    case 241 /* CaseBlock */:
+                        return emitCaseBlock(node);
+                    case 242 /* NamespaceExportDeclaration */:
+                        return emitNamespaceExportDeclaration(node);
+                    case 243 /* ImportEqualsDeclaration */:
+                        return emitImportEqualsDeclaration(node);
+                    case 244 /* ImportDeclaration */:
+                        return emitImportDeclaration(node);
+                    case 245 /* ImportClause */:
+                        return emitImportClause(node);
+                    case 246 /* NamespaceImport */:
+                        return emitNamespaceImport(node);
+                    case 247 /* NamedImports */:
+                        return emitNamedImports(node);
+                    case 248 /* ImportSpecifier */:
+                        return emitImportSpecifier(node);
+                    case 249 /* ExportAssignment */:
+                        return emitExportAssignment(node);
+                    case 250 /* ExportDeclaration */:
+                        return emitExportDeclaration(node);
+                    case 251 /* NamedExports */:
+                        return emitNamedExports(node);
+                    case 252 /* ExportSpecifier */:
+                        return emitExportSpecifier(node);
+                    case 253 /* MissingDeclaration */:
+                        return;
+                    // Module references
+                    case 254 /* ExternalModuleReference */:
+                        return emitExternalModuleReference(node);
+                    // JSX (non-expression)
+                    case 10 /* JsxText */:
+                        return emitJsxText(node);
+                    case 257 /* JsxOpeningElement */:
+                    case 260 /* JsxOpeningFragment */:
+                        return emitJsxOpeningElementOrFragment(node);
+                    case 258 /* JsxClosingElement */:
+                    case 261 /* JsxClosingFragment */:
+                        return emitJsxClosingElementOrFragment(node);
+                    case 262 /* JsxAttribute */:
+                        return emitJsxAttribute(node);
+                    case 263 /* JsxAttributes */:
+                        return emitJsxAttributes(node);
+                    case 264 /* JsxSpreadAttribute */:
+                        return emitJsxSpreadAttribute(node);
+                    case 265 /* JsxExpression */:
+                        return emitJsxExpression(node);
+                    // Clauses
+                    case 266 /* CaseClause */:
+                        return emitCaseClause(node);
+                    case 267 /* DefaultClause */:
+                        return emitDefaultClause(node);
+                    case 268 /* HeritageClause */:
+                        return emitHeritageClause(node);
+                    case 269 /* CatchClause */:
+                        return emitCatchClause(node);
+                    // Property assignments
+                    case 270 /* PropertyAssignment */:
+                        return emitPropertyAssignment(node);
+                    case 271 /* ShorthandPropertyAssignment */:
+                        return emitShorthandPropertyAssignment(node);
+                    case 272 /* SpreadAssignment */:
+                        return emitSpreadAssignment(node);
+                    // Enum
+                    case 273 /* EnumMember */:
+                        return emitEnumMember(node);
+                    // JSDoc nodes (ignored)
+                    // Transformation nodes (ignored)
+                }
+                if (ts.isExpression(node)) {
+                    hint = 1 /* Expression */;
+                    node = trySubstituteNode(1 /* Expression */, node);
+                }
+                else if (ts.isToken(node)) {
+                    return writeTokenNode(node, writePunctuation);
+                }
+            }
+            if (hint === 1 /* Expression */) {
+                switch (node.kind) {
+                    // Literals
+                    case 8 /* NumericLiteral */:
+                        return emitNumericLiteral(node);
+                    case 9 /* StringLiteral */:
+                    case 12 /* RegularExpressionLiteral */:
+                    case 13 /* NoSubstitutionTemplateLiteral */:
+                        return emitLiteral(node);
+                    // Identifiers
+                    case 71 /* Identifier */:
+                        return emitIdentifier(node);
+                    // Reserved words
+                    case 86 /* FalseKeyword */:
+                    case 95 /* NullKeyword */:
+                    case 97 /* SuperKeyword */:
+                    case 101 /* TrueKeyword */:
+                    case 99 /* ThisKeyword */:
+                    case 91 /* ImportKeyword */:
+                        writeTokenNode(node, writeKeyword);
+                        return;
+                    // Expressions
+                    case 183 /* ArrayLiteralExpression */:
+                        return emitArrayLiteralExpression(node);
+                    case 184 /* ObjectLiteralExpression */:
+                        return emitObjectLiteralExpression(node);
+                    case 185 /* PropertyAccessExpression */:
+                        return emitPropertyAccessExpression(node);
+                    case 186 /* ElementAccessExpression */:
+                        return emitElementAccessExpression(node);
+                    case 187 /* CallExpression */:
+                        return emitCallExpression(node);
+                    case 188 /* NewExpression */:
+                        return emitNewExpression(node);
+                    case 189 /* TaggedTemplateExpression */:
+                        return emitTaggedTemplateExpression(node);
+                    case 190 /* TypeAssertionExpression */:
+                        return emitTypeAssertionExpression(node);
+                    case 191 /* ParenthesizedExpression */:
+                        return emitParenthesizedExpression(node);
+                    case 192 /* FunctionExpression */:
+                        return emitFunctionExpression(node);
+                    case 193 /* ArrowFunction */:
+                        return emitArrowFunction(node);
+                    case 194 /* DeleteExpression */:
+                        return emitDeleteExpression(node);
+                    case 195 /* TypeOfExpression */:
+                        return emitTypeOfExpression(node);
+                    case 196 /* VoidExpression */:
+                        return emitVoidExpression(node);
+                    case 197 /* AwaitExpression */:
+                        return emitAwaitExpression(node);
+                    case 198 /* PrefixUnaryExpression */:
+                        return emitPrefixUnaryExpression(node);
+                    case 199 /* PostfixUnaryExpression */:
+                        return emitPostfixUnaryExpression(node);
+                    case 200 /* BinaryExpression */:
+                        return emitBinaryExpression(node);
+                    case 201 /* ConditionalExpression */:
+                        return emitConditionalExpression(node);
+                    case 202 /* TemplateExpression */:
+                        return emitTemplateExpression(node);
+                    case 203 /* YieldExpression */:
+                        return emitYieldExpression(node);
+                    case 204 /* SpreadElement */:
+                        return emitSpreadExpression(node);
+                    case 205 /* ClassExpression */:
+                        return emitClassExpression(node);
+                    case 206 /* OmittedExpression */:
+                        return;
+                    case 208 /* AsExpression */:
+                        return emitAsExpression(node);
+                    case 209 /* NonNullExpression */:
+                        return emitNonNullExpression(node);
+                    case 210 /* MetaProperty */:
+                        return emitMetaProperty(node);
+                    // JSX
+                    case 255 /* JsxElement */:
+                        return emitJsxElement(node);
+                    case 256 /* JsxSelfClosingElement */:
+                        return emitJsxSelfClosingElement(node);
+                    case 259 /* JsxFragment */:
+                        return emitJsxFragment(node);
+                    // Transformation nodes
+                    case 301 /* PartiallyEmittedExpression */:
+                        return emitPartiallyEmittedExpression(node);
+                    case 302 /* CommaListExpression */:
+                        return emitCommaList(node);
+                }
+            }
+        }
+        function emitMappedTypeParameter(node) {
+            emit(node.name);
+            writeSpace();
+            writeKeyword("in");
+            writeSpace();
+            emit(node.constraint);
+        }
+        function trySubstituteNode(hint, node) {
+            return node && substituteNode && substituteNode(hint, node) || node;
+        }
+        function emitHelpers(node) {
+            var helpersEmitted = false;
+            var bundle = node.kind === 275 /* Bundle */ ? node : undefined;
+            if (bundle && moduleKind === ts.ModuleKind.None) {
+                return;
+            }
+            var numNodes = bundle ? bundle.sourceFiles.length : 1;
+            for (var i = 0; i < numNodes; i++) {
+                var currentNode = bundle ? bundle.sourceFiles[i] : node;
+                var sourceFile = ts.isSourceFile(currentNode) ? currentNode : currentSourceFile;
+                var shouldSkip = printerOptions.noEmitHelpers || ts.getExternalHelpersModuleName(sourceFile) !== undefined;
+                var shouldBundle = ts.isSourceFile(currentNode) && !isOwnFileEmit;
+                var helpers = ts.getEmitHelpers(currentNode);
+                if (helpers) {
+                    for (var _a = 0, _b = ts.stableSort(helpers, ts.compareEmitHelpers); _a < _b.length; _a++) {
+                        var helper = _b[_a];
+                        if (!helper.scoped) {
+                            // Skip the helper if it can be skipped and the noEmitHelpers compiler
+                            // option is set, or if it can be imported and the importHelpers compiler
+                            // option is set.
+                            if (shouldSkip)
+                                continue;
+                            // Skip the helper if it can be bundled but hasn't already been emitted and we
+                            // are emitting a bundled module.
+                            if (shouldBundle) {
+                                if (bundledHelpers.get(helper.name)) {
+                                    continue;
+                                }
+                                bundledHelpers.set(helper.name, true);
+                            }
+                        }
+                        else if (bundle) {
+                            // Skip the helper if it is scoped and we are emitting bundled helpers
+                            continue;
+                        }
+                        if (typeof helper.text === "string") {
+                            writeLines(helper.text);
+                        }
+                        else {
+                            writeLines(helper.text(makeFileLevelOptmiisticUniqueName));
+                        }
+                        helpersEmitted = true;
+                    }
+                }
+            }
+            return helpersEmitted;
+        }
+        //
+        // Literals/Pseudo-literals
+        //
+        // SyntaxKind.NumericLiteral
+        function emitNumericLiteral(node) {
+            emitLiteral(node);
+        }
+        // SyntaxKind.StringLiteral
+        // SyntaxKind.RegularExpressionLiteral
+        // SyntaxKind.NoSubstitutionTemplateLiteral
+        // SyntaxKind.TemplateHead
+        // SyntaxKind.TemplateMiddle
+        // SyntaxKind.TemplateTail
+        function emitLiteral(node) {
+            var text = getLiteralTextOfNode(node);
+            if ((printerOptions.sourceMap || printerOptions.inlineSourceMap)
+                && (node.kind === 9 /* StringLiteral */ || ts.isTemplateLiteralKind(node.kind))) {
+                writeLiteral(text);
+            }
+            else {
+                // Quick info expects all literals to be called with writeStringLiteral, as there's no specific type for numberLiterals
+                writeStringLiteral(text);
+            }
+        }
+        // SyntaxKind.UnparsedSource
+        function emitUnparsedSource(unparsed) {
+            writer.rawWrite(unparsed.text);
+        }
+        //
+        // Identifiers
+        //
+        function emitIdentifier(node) {
+            var writeText = node.symbol ? writeSymbol : write;
+            writeText(getTextOfNode(node, /*includeTrivia*/ false), node.symbol);
+            emitList(node, node.typeArguments, 26896 /* TypeParameters */); // Call emitList directly since it could be an array of TypeParameterDeclarations _or_ type arguments
+        }
+        //
+        // Names
+        //
+        function emitQualifiedName(node) {
+            emitEntityName(node.left);
+            writePunctuation(".");
+            emit(node.right);
+        }
+        function emitEntityName(node) {
+            if (node.kind === 71 /* Identifier */) {
+                emitExpression(node);
+            }
+            else {
+                emit(node);
+            }
+        }
+        function emitComputedPropertyName(node) {
+            writePunctuation("[");
+            emitExpression(node.expression);
+            writePunctuation("]");
+        }
+        //
+        // Signature elements
+        //
+        function emitTypeParameter(node) {
+            emit(node.name);
+            if (node.constraint) {
+                writeSpace();
+                writeKeyword("extends");
+                writeSpace();
+                emit(node.constraint);
+            }
+            if (node.default) {
+                writeSpace();
+                writeOperator("=");
+                writeSpace();
+                emit(node.default);
+            }
+        }
+        function emitParameter(node) {
+            emitDecorators(node, node.decorators);
+            emitModifiers(node, node.modifiers);
+            emit(node.dotDotDotToken);
+            emitNodeWithWriter(node.name, writeParameter);
+            emit(node.questionToken);
+            if (node.parent && node.parent.kind === 284 /* JSDocFunctionType */ && !node.name) {
+                emit(node.type);
+            }
+            else {
+                emitTypeAnnotation(node.type);
+            }
+            // The comment position has to fallback to any present node within the parameterdeclaration because as it turns out, the parser can make parameter declarations with _just_ an initializer.
+            emitInitializer(node.initializer, node.type ? node.type.end : node.questionToken ? node.questionToken.end : node.name ? node.name.end : node.modifiers ? node.modifiers.end : node.decorators ? node.decorators.end : node.pos, node);
+        }
+        function emitDecorator(decorator) {
+            writePunctuation("@");
+            emitExpression(decorator.expression);
+        }
+        //
+        // Type members
+        //
+        function emitPropertySignature(node) {
+            emitDecorators(node, node.decorators);
+            emitModifiers(node, node.modifiers);
+            emitNodeWithWriter(node.name, writeProperty);
+            emit(node.questionToken);
+            emitTypeAnnotation(node.type);
+            writeSemicolon();
+        }
+        function emitPropertyDeclaration(node) {
+            emitDecorators(node, node.decorators);
+            emitModifiers(node, node.modifiers);
+            emit(node.name);
+            emit(node.questionToken);
+            emit(node.exclamationToken);
+            emitTypeAnnotation(node.type);
+            emitInitializer(node.initializer, node.type ? node.type.end : node.questionToken ? node.questionToken.end : node.name.end, node);
+            writeSemicolon();
+        }
+        function emitMethodSignature(node) {
+            pushNameGenerationScope(node);
+            emitDecorators(node, node.decorators);
+            emitModifiers(node, node.modifiers);
+            emit(node.name);
+            emit(node.questionToken);
+            emitTypeParameters(node, node.typeParameters);
+            emitParameters(node, node.parameters);
+            emitTypeAnnotation(node.type);
+            writeSemicolon();
+            popNameGenerationScope(node);
+        }
+        function emitMethodDeclaration(node) {
+            emitDecorators(node, node.decorators);
+            emitModifiers(node, node.modifiers);
+            emit(node.asteriskToken);
+            emit(node.name);
+            emit(node.questionToken);
+            emitSignatureAndBody(node, emitSignatureHead);
+        }
+        function emitConstructor(node) {
+            emitModifiers(node, node.modifiers);
+            writeKeyword("constructor");
+            emitSignatureAndBody(node, emitSignatureHead);
+        }
+        function emitAccessorDeclaration(node) {
+            emitDecorators(node, node.decorators);
+            emitModifiers(node, node.modifiers);
+            writeKeyword(node.kind === 156 /* GetAccessor */ ? "get" : "set");
+            writeSpace();
+            emit(node.name);
+            emitSignatureAndBody(node, emitSignatureHead);
+        }
+        function emitCallSignature(node) {
+            pushNameGenerationScope(node);
+            emitDecorators(node, node.decorators);
+            emitModifiers(node, node.modifiers);
+            emitTypeParameters(node, node.typeParameters);
+            emitParameters(node, node.parameters);
+            emitTypeAnnotation(node.type);
+            writeSemicolon();
+            popNameGenerationScope(node);
+        }
+        function emitConstructSignature(node) {
+            pushNameGenerationScope(node);
+            emitDecorators(node, node.decorators);
+            emitModifiers(node, node.modifiers);
+            writeKeyword("new");
+            writeSpace();
+            emitTypeParameters(node, node.typeParameters);
+            emitParameters(node, node.parameters);
+            emitTypeAnnotation(node.type);
+            writeSemicolon();
+            popNameGenerationScope(node);
+        }
+        function emitIndexSignature(node) {
+            emitDecorators(node, node.decorators);
+            emitModifiers(node, node.modifiers);
+            emitParametersForIndexSignature(node, node.parameters);
+            emitTypeAnnotation(node.type);
+            writeSemicolon();
+        }
+        function emitSemicolonClassElement() {
+            writeSemicolon();
+        }
+        //
+        // Types
+        //
+        function emitTypePredicate(node) {
+            emit(node.parameterName);
+            writeSpace();
+            writeKeyword("is");
+            writeSpace();
+            emit(node.type);
+        }
+        function emitTypeReference(node) {
+            emit(node.typeName);
+            emitTypeArguments(node, node.typeArguments);
+        }
+        function emitFunctionType(node) {
+            pushNameGenerationScope(node);
+            emitTypeParameters(node, node.typeParameters);
+            emitParametersForArrow(node, node.parameters);
+            writeSpace();
+            writePunctuation("=>");
+            writeSpace();
+            emit(node.type);
+            popNameGenerationScope(node);
+        }
+        function emitJSDocFunctionType(node) {
+            write("function");
+            emitParameters(node, node.parameters);
+            write(":");
+            emit(node.type);
+        }
+        function emitJSDocNullableType(node) {
+            write("?");
+            emit(node.type);
+        }
+        function emitJSDocNonNullableType(node) {
+            write("!");
+            emit(node.type);
+        }
+        function emitJSDocOptionalType(node) {
+            emit(node.type);
+            write("=");
+        }
+        function emitConstructorType(node) {
+            pushNameGenerationScope(node);
+            writeKeyword("new");
+            writeSpace();
+            emitTypeParameters(node, node.typeParameters);
+            emitParameters(node, node.parameters);
+            writeSpace();
+            writePunctuation("=>");
+            writeSpace();
+            emit(node.type);
+            popNameGenerationScope(node);
+        }
+        function emitTypeQuery(node) {
+            writeKeyword("typeof");
+            writeSpace();
+            emit(node.exprName);
+        }
+        function emitTypeLiteral(node) {
+            writePunctuation("{");
+            var flags = ts.getEmitFlags(node) & 1 /* SingleLine */ ? 384 /* SingleLineTypeLiteralMembers */ : 16449 /* MultiLineTypeLiteralMembers */;
+            emitList(node, node.members, flags | 262144 /* NoSpaceIfEmpty */);
+            writePunctuation("}");
+        }
+        function emitArrayType(node) {
+            emit(node.elementType);
+            writePunctuation("[");
+            writePunctuation("]");
+        }
+        function emitJSDocVariadicType(node) {
+            write("...");
+            emit(node.type);
+        }
+        function emitTupleType(node) {
+            writePunctuation("[");
+            emitList(node, node.elementTypes, 272 /* TupleTypeElements */);
+            writePunctuation("]");
+        }
+        function emitUnionType(node) {
+            emitList(node, node.types, 260 /* UnionTypeConstituents */);
+        }
+        function emitIntersectionType(node) {
+            emitList(node, node.types, 264 /* IntersectionTypeConstituents */);
+        }
+        function emitConditionalType(node) {
+            emit(node.checkType);
+            writeSpace();
+            writeKeyword("extends");
+            writeSpace();
+            emit(node.extendsType);
+            writeSpace();
+            writePunctuation("?");
+            writeSpace();
+            emit(node.trueType);
+            writeSpace();
+            writePunctuation(":");
+            writeSpace();
+            emit(node.falseType);
+        }
+        function emitInferType(node) {
+            writeKeyword("infer");
+            writeSpace();
+            emit(node.typeParameter);
+        }
+        function emitParenthesizedType(node) {
+            writePunctuation("(");
+            emit(node.type);
+            writePunctuation(")");
+        }
+        function emitThisType() {
+            writeKeyword("this");
+        }
+        function emitTypeOperator(node) {
+            writeTokenText(node.operator, writeKeyword);
+            writeSpace();
+            emit(node.type);
+        }
+        function emitIndexedAccessType(node) {
+            emit(node.objectType);
+            writePunctuation("[");
+            emit(node.indexType);
+            writePunctuation("]");
+        }
+        function emitMappedType(node) {
+            var emitFlags = ts.getEmitFlags(node);
+            writePunctuation("{");
+            if (emitFlags & 1 /* SingleLine */) {
+                writeSpace();
+            }
+            else {
+                writeLine();
+                increaseIndent();
+            }
+            if (node.readonlyToken) {
+                emit(node.readonlyToken);
+                if (node.readonlyToken.kind !== 132 /* ReadonlyKeyword */) {
+                    writeKeyword("readonly");
+                }
+                writeSpace();
+            }
+            writePunctuation("[");
+            var pipelinePhase = getPipelinePhase(0 /* Notification */, 3 /* MappedTypeParameter */);
+            pipelinePhase(3 /* MappedTypeParameter */, node.typeParameter);
+            writePunctuation("]");
+            if (node.questionToken) {
+                emit(node.questionToken);
+                if (node.questionToken.kind !== 55 /* QuestionToken */) {
+                    writePunctuation("?");
+                }
+            }
+            writePunctuation(":");
+            writeSpace();
+            emit(node.type);
+            writeSemicolon();
+            if (emitFlags & 1 /* SingleLine */) {
+                writeSpace();
+            }
+            else {
+                writeLine();
+                decreaseIndent();
+            }
+            writePunctuation("}");
+        }
+        function emitLiteralType(node) {
+            emitExpression(node.literal);
+        }
+        function emitImportTypeNode(node) {
+            if (node.isTypeOf) {
+                writeKeyword("typeof");
+                writeSpace();
+            }
+            writeKeyword("import");
+            writePunctuation("(");
+            emit(node.argument);
+            writePunctuation(")");
+            if (node.qualifier) {
+                writePunctuation(".");
+                emit(node.qualifier);
+            }
+            emitTypeArguments(node, node.typeArguments);
+        }
+        //
+        // Binding patterns
+        //
+        function emitObjectBindingPattern(node) {
+            writePunctuation("{");
+            emitList(node, node.elements, 262576 /* ObjectBindingPatternElements */);
+            writePunctuation("}");
+        }
+        function emitArrayBindingPattern(node) {
+            writePunctuation("[");
+            emitList(node, node.elements, 262448 /* ArrayBindingPatternElements */);
+            writePunctuation("]");
+        }
+        function emitBindingElement(node) {
+            emit(node.dotDotDotToken);
+            if (node.propertyName) {
+                emit(node.propertyName);
+                writePunctuation(":");
+                writeSpace();
+            }
+            emit(node.name);
+            emitInitializer(node.initializer, node.name.end, node);
+        }
+        //
+        // Expressions
+        //
+        function emitArrayLiteralExpression(node) {
+            var elements = node.elements;
+            var preferNewLine = node.multiLine ? 32768 /* PreferNewLine */ : 0 /* None */;
+            emitExpressionList(node, elements, 4466 /* ArrayLiteralExpressionElements */ | preferNewLine);
+        }
+        function emitObjectLiteralExpression(node) {
+            ts.forEach(node.properties, generateMemberNames);
+            var indentedFlag = ts.getEmitFlags(node) & 65536 /* Indented */;
+            if (indentedFlag) {
+                increaseIndent();
+            }
+            var preferNewLine = node.multiLine ? 32768 /* PreferNewLine */ : 0 /* None */;
+            var allowTrailingComma = currentSourceFile.languageVersion >= 1 /* ES5 */ && !ts.isJsonSourceFile(currentSourceFile) ? 32 /* AllowTrailingComma */ : 0 /* None */;
+            emitList(node, node.properties, 263122 /* ObjectLiteralExpressionProperties */ | allowTrailingComma | preferNewLine);
+            if (indentedFlag) {
+                decreaseIndent();
+            }
+        }
+        function emitPropertyAccessExpression(node) {
+            var indentBeforeDot = false;
+            var indentAfterDot = false;
+            if (!(ts.getEmitFlags(node) & 131072 /* NoIndentation */)) {
+                var dotRangeStart = node.expression.end;
+                var dotRangeEnd = ts.skipTrivia(currentSourceFile.text, node.expression.end) + 1;
+                var dotToken = ts.createToken(23 /* DotToken */);
+                dotToken.pos = dotRangeStart;
+                dotToken.end = dotRangeEnd;
+                indentBeforeDot = needsIndentation(node, node.expression, dotToken);
+                indentAfterDot = needsIndentation(node, dotToken, node.name);
+            }
+            emitExpression(node.expression);
+            increaseIndentIf(indentBeforeDot);
+            var shouldEmitDotDot = !indentBeforeDot && needsDotDotForPropertyAccess(node.expression);
+            if (shouldEmitDotDot) {
+                writePunctuation(".");
+            }
+            emitTokenWithComment(23 /* DotToken */, node.expression.end, writePunctuation, node);
+            increaseIndentIf(indentAfterDot);
+            emit(node.name);
+            decreaseIndentIf(indentBeforeDot, indentAfterDot);
+        }
+        // 1..toString is a valid property access, emit a dot after the literal
+        // Also emit a dot if expression is a integer const enum value - it will appear in generated code as numeric literal
+        function needsDotDotForPropertyAccess(expression) {
+            expression = ts.skipPartiallyEmittedExpressions(expression);
+            if (ts.isNumericLiteral(expression)) {
+                // check if numeric literal is a decimal literal that was originally written with a dot
+                var text = getLiteralTextOfNode(expression);
+                return !expression.numericLiteralFlags
+                    && !ts.stringContains(text, ts.tokenToString(23 /* DotToken */));
+            }
+            else if (ts.isPropertyAccessExpression(expression) || ts.isElementAccessExpression(expression)) {
+                // check if constant enum value is integer
+                var constantValue = ts.getConstantValue(expression);
+                // isFinite handles cases when constantValue is undefined
+                return typeof constantValue === "number" && isFinite(constantValue)
+                    && Math.floor(constantValue) === constantValue
+                    && printerOptions.removeComments;
+            }
+        }
+        function emitElementAccessExpression(node) {
+            emitExpression(node.expression);
+            emitTokenWithComment(21 /* OpenBracketToken */, node.expression.end, writePunctuation, node);
+            emitExpression(node.argumentExpression);
+            emitTokenWithComment(22 /* CloseBracketToken */, node.argumentExpression.end, writePunctuation, node);
+        }
+        function emitCallExpression(node) {
+            emitExpression(node.expression);
+            emitTypeArguments(node, node.typeArguments);
+            emitExpressionList(node, node.arguments, 1296 /* CallExpressionArguments */);
+        }
+        function emitNewExpression(node) {
+            emitTokenWithComment(94 /* NewKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            emitExpression(node.expression);
+            emitTypeArguments(node, node.typeArguments);
+            emitExpressionList(node, node.arguments, 9488 /* NewExpressionArguments */);
+        }
+        function emitTaggedTemplateExpression(node) {
+            emitExpression(node.tag);
+            emitTypeArguments(node, node.typeArguments);
+            writeSpace();
+            emitExpression(node.template);
+        }
+        function emitTypeAssertionExpression(node) {
+            writePunctuation("<");
+            emit(node.type);
+            writePunctuation(">");
+            emitExpression(node.expression);
+        }
+        function emitParenthesizedExpression(node) {
+            var openParenPos = emitTokenWithComment(19 /* OpenParenToken */, node.pos, writePunctuation, node);
+            emitExpression(node.expression);
+            emitTokenWithComment(20 /* CloseParenToken */, node.expression ? node.expression.end : openParenPos, writePunctuation, node);
+        }
+        function emitFunctionExpression(node) {
+            generateNameIfNeeded(node.name);
+            emitFunctionDeclarationOrExpression(node);
+        }
+        function emitArrowFunction(node) {
+            emitDecorators(node, node.decorators);
+            emitModifiers(node, node.modifiers);
+            emitSignatureAndBody(node, emitArrowFunctionHead);
+        }
+        function emitArrowFunctionHead(node) {
+            emitTypeParameters(node, node.typeParameters);
+            emitParametersForArrow(node, node.parameters);
+            emitTypeAnnotation(node.type);
+            writeSpace();
+            emit(node.equalsGreaterThanToken);
+        }
+        function emitDeleteExpression(node) {
+            emitTokenWithComment(80 /* DeleteKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            emitExpression(node.expression);
+        }
+        function emitTypeOfExpression(node) {
+            emitTokenWithComment(103 /* TypeOfKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            emitExpression(node.expression);
+        }
+        function emitVoidExpression(node) {
+            emitTokenWithComment(105 /* VoidKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            emitExpression(node.expression);
+        }
+        function emitAwaitExpression(node) {
+            emitTokenWithComment(121 /* AwaitKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            emitExpression(node.expression);
+        }
+        function emitPrefixUnaryExpression(node) {
+            writeTokenText(node.operator, writeOperator);
+            if (shouldEmitWhitespaceBeforeOperand(node)) {
+                writeSpace();
+            }
+            emitExpression(node.operand);
+        }
+        function shouldEmitWhitespaceBeforeOperand(node) {
+            // In some cases, we need to emit a space between the operator and the operand. One obvious case
+            // is when the operator is an identifier, like delete or typeof. We also need to do this for plus
+            // and minus expressions in certain cases. Specifically, consider the following two cases (parens
+            // are just for clarity of exposition, and not part of the source code):
+            //
+            //  (+(+1))
+            //  (+(++1))
+            //
+            // We need to emit a space in both cases. In the first case, the absence of a space will make
+            // the resulting expression a prefix increment operation. And in the second, it will make the resulting
+            // expression a prefix increment whose operand is a plus expression - (++(+x))
+            // The same is true of minus of course.
+            var operand = node.operand;
+            return operand.kind === 198 /* PrefixUnaryExpression */
+                && ((node.operator === 37 /* PlusToken */ && (operand.operator === 37 /* PlusToken */ || operand.operator === 43 /* PlusPlusToken */))
+                    || (node.operator === 38 /* MinusToken */ && (operand.operator === 38 /* MinusToken */ || operand.operator === 44 /* MinusMinusToken */)));
+        }
+        function emitPostfixUnaryExpression(node) {
+            emitExpression(node.operand);
+            writeTokenText(node.operator, writeOperator);
+        }
+        function emitBinaryExpression(node) {
+            var isCommaOperator = node.operatorToken.kind !== 26 /* CommaToken */;
+            var indentBeforeOperator = needsIndentation(node, node.left, node.operatorToken);
+            var indentAfterOperator = needsIndentation(node, node.operatorToken, node.right);
+            emitExpression(node.left);
+            increaseIndentIf(indentBeforeOperator, isCommaOperator ? " " : undefined);
+            emitLeadingCommentsOfPosition(node.operatorToken.pos);
+            writeTokenNode(node.operatorToken, writeOperator);
+            emitTrailingCommentsOfPosition(node.operatorToken.end, /*prefixSpace*/ true); // Binary operators should have a space before the comment starts
+            increaseIndentIf(indentAfterOperator, " ");
+            emitExpression(node.right);
+            decreaseIndentIf(indentBeforeOperator, indentAfterOperator);
+        }
+        function emitConditionalExpression(node) {
+            var indentBeforeQuestion = needsIndentation(node, node.condition, node.questionToken);
+            var indentAfterQuestion = needsIndentation(node, node.questionToken, node.whenTrue);
+            var indentBeforeColon = needsIndentation(node, node.whenTrue, node.colonToken);
+            var indentAfterColon = needsIndentation(node, node.colonToken, node.whenFalse);
+            emitExpression(node.condition);
+            increaseIndentIf(indentBeforeQuestion, " ");
+            emit(node.questionToken);
+            increaseIndentIf(indentAfterQuestion, " ");
+            emitExpression(node.whenTrue);
+            decreaseIndentIf(indentBeforeQuestion, indentAfterQuestion);
+            increaseIndentIf(indentBeforeColon, " ");
+            emit(node.colonToken);
+            increaseIndentIf(indentAfterColon, " ");
+            emitExpression(node.whenFalse);
+            decreaseIndentIf(indentBeforeColon, indentAfterColon);
+        }
+        function emitTemplateExpression(node) {
+            emit(node.head);
+            emitList(node, node.templateSpans, 131072 /* TemplateExpressionSpans */);
+        }
+        function emitYieldExpression(node) {
+            emitTokenWithComment(116 /* YieldKeyword */, node.pos, writeKeyword, node);
+            emit(node.asteriskToken);
+            emitExpressionWithLeadingSpace(node.expression);
+        }
+        function emitSpreadExpression(node) {
+            writePunctuation("...");
+            emitExpression(node.expression);
+        }
+        function emitClassExpression(node) {
+            generateNameIfNeeded(node.name);
+            emitClassDeclarationOrExpression(node);
+        }
+        function emitExpressionWithTypeArguments(node) {
+            emitExpression(node.expression);
+            emitTypeArguments(node, node.typeArguments);
+        }
+        function emitAsExpression(node) {
+            emitExpression(node.expression);
+            if (node.type) {
+                writeSpace();
+                writeKeyword("as");
+                writeSpace();
+                emit(node.type);
+            }
+        }
+        function emitNonNullExpression(node) {
+            emitExpression(node.expression);
+            writeOperator("!");
+        }
+        function emitMetaProperty(node) {
+            writeToken(node.keywordToken, node.pos, writePunctuation);
+            writePunctuation(".");
+            emit(node.name);
+        }
+        //
+        // Misc
+        //
+        function emitTemplateSpan(node) {
+            emitExpression(node.expression);
+            emit(node.literal);
+        }
+        //
+        // Statements
+        //
+        function emitBlock(node) {
+            emitBlockStatements(node, /*forceSingleLine*/ !node.multiLine && isEmptyBlock(node));
+        }
+        function emitBlockStatements(node, forceSingleLine) {
+            emitTokenWithComment(17 /* OpenBraceToken */, node.pos, writePunctuation, /*contextNode*/ node);
+            var format = forceSingleLine || ts.getEmitFlags(node) & 1 /* SingleLine */ ? 384 /* SingleLineBlockStatements */ : 65 /* MultiLineBlockStatements */;
+            emitList(node, node.statements, format);
+            emitTokenWithComment(18 /* CloseBraceToken */, node.statements.end, writePunctuation, /*contextNode*/ node, /*indentLeading*/ !!(format & 1 /* MultiLine */));
+        }
+        function emitVariableStatement(node) {
+            emitModifiers(node, node.modifiers);
+            emit(node.declarationList);
+            writeSemicolon();
+        }
+        function emitEmptyStatement() {
+            writeSemicolon();
+        }
+        function emitExpressionStatement(node) {
+            emitExpression(node.expression);
+            if (!ts.isJsonSourceFile(currentSourceFile)) {
+                writeSemicolon();
+            }
+        }
+        function emitIfStatement(node) {
+            var openParenPos = emitTokenWithComment(90 /* IfKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            emitTokenWithComment(19 /* OpenParenToken */, openParenPos, writePunctuation, node);
+            emitExpression(node.expression);
+            emitTokenWithComment(20 /* CloseParenToken */, node.expression.end, writePunctuation, node);
+            emitEmbeddedStatement(node, node.thenStatement);
+            if (node.elseStatement) {
+                writeLineOrSpace(node);
+                emitTokenWithComment(82 /* ElseKeyword */, node.thenStatement.end, writeKeyword, node);
+                if (node.elseStatement.kind === 217 /* IfStatement */) {
+                    writeSpace();
+                    emit(node.elseStatement);
+                }
+                else {
+                    emitEmbeddedStatement(node, node.elseStatement);
+                }
+            }
+        }
+        function emitWhileClause(node, startPos) {
+            var openParenPos = emitTokenWithComment(106 /* WhileKeyword */, startPos, writeKeyword, node);
+            writeSpace();
+            emitTokenWithComment(19 /* OpenParenToken */, openParenPos, writePunctuation, node);
+            emitExpression(node.expression);
+            emitTokenWithComment(20 /* CloseParenToken */, node.expression.end, writePunctuation, node);
+        }
+        function emitDoStatement(node) {
+            emitTokenWithComment(81 /* DoKeyword */, node.pos, writeKeyword, node);
+            emitEmbeddedStatement(node, node.statement);
+            if (ts.isBlock(node.statement)) {
+                writeSpace();
+            }
+            else {
+                writeLineOrSpace(node);
+            }
+            emitWhileClause(node, node.statement.end);
+            writePunctuation(";");
+        }
+        function emitWhileStatement(node) {
+            emitWhileClause(node, node.pos);
+            emitEmbeddedStatement(node, node.statement);
+        }
+        function emitForStatement(node) {
+            var openParenPos = emitTokenWithComment(88 /* ForKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            var pos = emitTokenWithComment(19 /* OpenParenToken */, openParenPos, writePunctuation, /*contextNode*/ node);
+            emitForBinding(node.initializer);
+            pos = emitTokenWithComment(25 /* SemicolonToken */, node.initializer ? node.initializer.end : pos, writeSemicolon, node);
+            emitExpressionWithLeadingSpace(node.condition);
+            pos = emitTokenWithComment(25 /* SemicolonToken */, node.condition ? node.condition.end : pos, writeSemicolon, node);
+            emitExpressionWithLeadingSpace(node.incrementor);
+            emitTokenWithComment(20 /* CloseParenToken */, node.incrementor ? node.incrementor.end : pos, writePunctuation, node);
+            emitEmbeddedStatement(node, node.statement);
+        }
+        function emitForInStatement(node) {
+            var openParenPos = emitTokenWithComment(88 /* ForKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            emitTokenWithComment(19 /* OpenParenToken */, openParenPos, writePunctuation, node);
+            emitForBinding(node.initializer);
+            writeSpace();
+            emitTokenWithComment(92 /* InKeyword */, node.initializer.end, writeKeyword, node);
+            writeSpace();
+            emitExpression(node.expression);
+            emitTokenWithComment(20 /* CloseParenToken */, node.expression.end, writePunctuation, node);
+            emitEmbeddedStatement(node, node.statement);
+        }
+        function emitForOfStatement(node) {
+            var openParenPos = emitTokenWithComment(88 /* ForKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            emitWithTrailingSpace(node.awaitModifier);
+            emitTokenWithComment(19 /* OpenParenToken */, openParenPos, writePunctuation, node);
+            emitForBinding(node.initializer);
+            writeSpace();
+            emitTokenWithComment(145 /* OfKeyword */, node.initializer.end, writeKeyword, node);
+            writeSpace();
+            emitExpression(node.expression);
+            emitTokenWithComment(20 /* CloseParenToken */, node.expression.end, writePunctuation, node);
+            emitEmbeddedStatement(node, node.statement);
+        }
+        function emitForBinding(node) {
+            if (node !== undefined) {
+                if (node.kind === 233 /* VariableDeclarationList */) {
+                    emit(node);
+                }
+                else {
+                    emitExpression(node);
+                }
+            }
+        }
+        function emitContinueStatement(node) {
+            emitTokenWithComment(77 /* ContinueKeyword */, node.pos, writeKeyword, node);
+            emitWithLeadingSpace(node.label);
+            writeSemicolon();
+        }
+        function emitBreakStatement(node) {
+            emitTokenWithComment(72 /* BreakKeyword */, node.pos, writeKeyword, node);
+            emitWithLeadingSpace(node.label);
+            writeSemicolon();
+        }
+        function emitTokenWithComment(token, pos, writer, contextNode, indentLeading) {
+            var node = ts.getParseTreeNode(contextNode);
+            var isSimilarNode = node && node.kind === contextNode.kind;
+            var startPos = pos;
+            if (isSimilarNode) {
+                pos = ts.skipTrivia(currentSourceFile.text, pos);
+            }
+            if (emitLeadingCommentsOfPosition && isSimilarNode && contextNode.pos !== startPos) {
+                var needsIndent = indentLeading && !ts.positionsAreOnSameLine(startPos, pos, currentSourceFile);
+                if (needsIndent) {
+                    increaseIndent();
+                }
+                emitLeadingCommentsOfPosition(startPos);
+                if (needsIndent) {
+                    decreaseIndent();
+                }
+            }
+            pos = writeTokenText(token, writer, pos);
+            if (emitTrailingCommentsOfPosition && isSimilarNode && contextNode.end !== pos) {
+                emitTrailingCommentsOfPosition(pos, /*prefixSpace*/ true);
+            }
+            return pos;
+        }
+        function emitReturnStatement(node) {
+            emitTokenWithComment(96 /* ReturnKeyword */, node.pos, writeKeyword, /*contextNode*/ node);
+            emitExpressionWithLeadingSpace(node.expression);
+            writeSemicolon();
+        }
+        function emitWithStatement(node) {
+            var openParenPos = emitTokenWithComment(107 /* WithKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            emitTokenWithComment(19 /* OpenParenToken */, openParenPos, writePunctuation, node);
+            emitExpression(node.expression);
+            emitTokenWithComment(20 /* CloseParenToken */, node.expression.end, writePunctuation, node);
+            emitEmbeddedStatement(node, node.statement);
+        }
+        function emitSwitchStatement(node) {
+            var openParenPos = emitTokenWithComment(98 /* SwitchKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            emitTokenWithComment(19 /* OpenParenToken */, openParenPos, writePunctuation, node);
+            emitExpression(node.expression);
+            emitTokenWithComment(20 /* CloseParenToken */, node.expression.end, writePunctuation, node);
+            writeSpace();
+            emit(node.caseBlock);
+        }
+        function emitLabeledStatement(node) {
+            emit(node.label);
+            emitTokenWithComment(56 /* ColonToken */, node.label.end, writePunctuation, node);
+            writeSpace();
+            emit(node.statement);
+        }
+        function emitThrowStatement(node) {
+            emitTokenWithComment(100 /* ThrowKeyword */, node.pos, writeKeyword, node);
+            emitExpressionWithLeadingSpace(node.expression);
+            writeSemicolon();
+        }
+        function emitTryStatement(node) {
+            emitTokenWithComment(102 /* TryKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            emit(node.tryBlock);
+            if (node.catchClause) {
+                writeLineOrSpace(node);
+                emit(node.catchClause);
+            }
+            if (node.finallyBlock) {
+                writeLineOrSpace(node);
+                emitTokenWithComment(87 /* FinallyKeyword */, (node.catchClause || node.tryBlock).end, writeKeyword, node);
+                writeSpace();
+                emit(node.finallyBlock);
+            }
+        }
+        function emitDebuggerStatement(node) {
+            writeToken(78 /* DebuggerKeyword */, node.pos, writeKeyword);
+            writeSemicolon();
+        }
+        //
+        // Declarations
+        //
+        function emitVariableDeclaration(node) {
+            emit(node.name);
+            emitTypeAnnotation(node.type);
+            emitInitializer(node.initializer, node.type ? node.type.end : node.name.end, node);
+        }
+        function emitVariableDeclarationList(node) {
+            writeKeyword(ts.isLet(node) ? "let" : ts.isConst(node) ? "const" : "var");
+            writeSpace();
+            emitList(node, node.declarations, 272 /* VariableDeclarationList */);
+        }
+        function emitFunctionDeclaration(node) {
+            emitFunctionDeclarationOrExpression(node);
+        }
+        function emitFunctionDeclarationOrExpression(node) {
+            emitDecorators(node, node.decorators);
+            emitModifiers(node, node.modifiers);
+            writeKeyword("function");
+            emit(node.asteriskToken);
+            writeSpace();
+            emitIdentifierName(node.name); // TODO: GH#18217
+            emitSignatureAndBody(node, emitSignatureHead);
+        }
+        function emitBlockCallback(_hint, body) {
+            emitBlockFunctionBody(body);
+        }
+        function emitSignatureAndBody(node, emitSignatureHead) {
+            var body = node.body;
+            if (body) {
+                if (ts.isBlock(body)) {
+                    var indentedFlag = ts.getEmitFlags(node) & 65536 /* Indented */;
+                    if (indentedFlag) {
+                        increaseIndent();
+                    }
+                    pushNameGenerationScope(node);
+                    ts.forEach(node.parameters, generateNames);
+                    generateNames(node.body);
+                    emitSignatureHead(node);
+                    if (onEmitNode) {
+                        onEmitNode(4 /* Unspecified */, body, emitBlockCallback);
+                    }
+                    else {
+                        emitBlockFunctionBody(body);
+                    }
+                    popNameGenerationScope(node);
+                    if (indentedFlag) {
+                        decreaseIndent();
+                    }
+                }
+                else {
+                    emitSignatureHead(node);
+                    writeSpace();
+                    emitExpression(body);
+                }
+            }
+            else {
+                emitSignatureHead(node);
+                writeSemicolon();
+            }
+        }
+        function emitSignatureHead(node) {
+            emitTypeParameters(node, node.typeParameters);
+            emitParameters(node, node.parameters);
+            emitTypeAnnotation(node.type);
+        }
+        function shouldEmitBlockFunctionBodyOnSingleLine(body) {
+            // We must emit a function body as a single-line body in the following case:
+            // * The body has NodeEmitFlags.SingleLine specified.
+            // We must emit a function body as a multi-line body in the following cases:
+            // * The body is explicitly marked as multi-line.
+            // * A non-synthesized body's start and end position are on different lines.
+            // * Any statement in the body starts on a new line.
+            if (ts.getEmitFlags(body) & 1 /* SingleLine */) {
+                return true;
+            }
+            if (body.multiLine) {
+                return false;
+            }
+            if (!ts.nodeIsSynthesized(body) && !ts.rangeIsOnSingleLine(body, currentSourceFile)) {
+                return false;
+            }
+            if (shouldWriteLeadingLineTerminator(body, body.statements, 2 /* PreserveLines */)
+                || shouldWriteClosingLineTerminator(body, body.statements, 2 /* PreserveLines */)) {
+                return false;
+            }
+            var previousStatement;
+            for (var _a = 0, _b = body.statements; _a < _b.length; _a++) {
+                var statement = _b[_a];
+                if (shouldWriteSeparatingLineTerminator(previousStatement, statement, 2 /* PreserveLines */)) {
+                    return false;
+                }
+                previousStatement = statement;
+            }
+            return true;
+        }
+        function emitBlockFunctionBody(body) {
+            writeSpace();
+            writePunctuation("{");
+            increaseIndent();
+            var emitBlockFunctionBody = shouldEmitBlockFunctionBodyOnSingleLine(body)
+                ? emitBlockFunctionBodyOnSingleLine
+                : emitBlockFunctionBodyWorker;
+            if (emitBodyWithDetachedComments) {
+                emitBodyWithDetachedComments(body, body.statements, emitBlockFunctionBody);
+            }
+            else {
+                emitBlockFunctionBody(body);
+            }
+            decreaseIndent();
+            writeToken(18 /* CloseBraceToken */, body.statements.end, writePunctuation, body);
+        }
+        function emitBlockFunctionBodyOnSingleLine(body) {
+            emitBlockFunctionBodyWorker(body, /*emitBlockFunctionBodyOnSingleLine*/ true);
+        }
+        function emitBlockFunctionBodyWorker(body, emitBlockFunctionBodyOnSingleLine) {
+            // Emit all the prologue directives (like "use strict").
+            var statementOffset = emitPrologueDirectives(body.statements, /*startWithNewLine*/ true);
+            var pos = writer.getTextPos();
+            emitHelpers(body);
+            if (statementOffset === 0 && pos === writer.getTextPos() && emitBlockFunctionBodyOnSingleLine) {
+                decreaseIndent();
+                emitList(body, body.statements, 384 /* SingleLineFunctionBodyStatements */);
+                increaseIndent();
+            }
+            else {
+                emitList(body, body.statements, 1 /* MultiLineFunctionBodyStatements */, statementOffset);
+            }
+        }
+        function emitClassDeclaration(node) {
+            emitClassDeclarationOrExpression(node);
+        }
+        function emitClassDeclarationOrExpression(node) {
+            ts.forEach(node.members, generateMemberNames);
+            emitDecorators(node, node.decorators);
+            emitModifiers(node, node.modifiers);
+            writeKeyword("class");
+            if (node.name) {
+                writeSpace();
+                emitIdentifierName(node.name);
+            }
+            var indentedFlag = ts.getEmitFlags(node) & 65536 /* Indented */;
+            if (indentedFlag) {
+                increaseIndent();
+            }
+            emitTypeParameters(node, node.typeParameters);
+            emitList(node, node.heritageClauses, 0 /* ClassHeritageClauses */);
+            writeSpace();
+            writePunctuation("{");
+            emitList(node, node.members, 65 /* ClassMembers */);
+            writePunctuation("}");
+            if (indentedFlag) {
+                decreaseIndent();
+            }
+        }
+        function emitInterfaceDeclaration(node) {
+            emitDecorators(node, node.decorators);
+            emitModifiers(node, node.modifiers);
+            writeKeyword("interface");
+            writeSpace();
+            emit(node.name);
+            emitTypeParameters(node, node.typeParameters);
+            emitList(node, node.heritageClauses, 256 /* HeritageClauses */);
+            writeSpace();
+            writePunctuation("{");
+            emitList(node, node.members, 65 /* InterfaceMembers */);
+            writePunctuation("}");
+        }
+        function emitTypeAliasDeclaration(node) {
+            emitDecorators(node, node.decorators);
+            emitModifiers(node, node.modifiers);
+            writeKeyword("type");
+            writeSpace();
+            emit(node.name);
+            emitTypeParameters(node, node.typeParameters);
+            writeSpace();
+            writePunctuation("=");
+            writeSpace();
+            emit(node.type);
+            writeSemicolon();
+        }
+        function emitEnumDeclaration(node) {
+            emitModifiers(node, node.modifiers);
+            writeKeyword("enum");
+            writeSpace();
+            emit(node.name);
+            writeSpace();
+            writePunctuation("{");
+            emitList(node, node.members, 81 /* EnumMembers */);
+            writePunctuation("}");
+        }
+        function emitModuleDeclaration(node) {
+            emitModifiers(node, node.modifiers);
+            if (~node.flags & 512 /* GlobalAugmentation */) {
+                writeKeyword(node.flags & 16 /* Namespace */ ? "namespace" : "module");
+                writeSpace();
+            }
+            emit(node.name);
+            var body = node.body;
+            if (!body)
+                return writeSemicolon();
+            while (body.kind === 239 /* ModuleDeclaration */) {
+                writePunctuation(".");
+                emit(body.name);
+                body = body.body;
+            }
+            writeSpace();
+            emit(body);
+        }
+        function emitModuleBlock(node) {
+            pushNameGenerationScope(node);
+            ts.forEach(node.statements, generateNames);
+            emitBlockStatements(node, /*forceSingleLine*/ isEmptyBlock(node));
+            popNameGenerationScope(node);
+        }
+        function emitCaseBlock(node) {
+            emitTokenWithComment(17 /* OpenBraceToken */, node.pos, writePunctuation, node);
+            emitList(node, node.clauses, 65 /* CaseBlockClauses */);
+            emitTokenWithComment(18 /* CloseBraceToken */, node.clauses.end, writePunctuation, node, /*indentLeading*/ true);
+        }
+        function emitImportEqualsDeclaration(node) {
+            emitModifiers(node, node.modifiers);
+            emitTokenWithComment(91 /* ImportKeyword */, node.modifiers ? node.modifiers.end : node.pos, writeKeyword, node);
+            writeSpace();
+            emit(node.name);
+            writeSpace();
+            emitTokenWithComment(58 /* EqualsToken */, node.name.end, writePunctuation, node);
+            writeSpace();
+            emitModuleReference(node.moduleReference);
+            writeSemicolon();
+        }
+        function emitModuleReference(node) {
+            if (node.kind === 71 /* Identifier */) {
+                emitExpression(node);
+            }
+            else {
+                emit(node);
+            }
+        }
+        function emitImportDeclaration(node) {
+            emitModifiers(node, node.modifiers);
+            emitTokenWithComment(91 /* ImportKeyword */, node.modifiers ? node.modifiers.end : node.pos, writeKeyword, node);
+            writeSpace();
+            if (node.importClause) {
+                emit(node.importClause);
+                writeSpace();
+                emitTokenWithComment(143 /* FromKeyword */, node.importClause.end, writeKeyword, node);
+                writeSpace();
+            }
+            emitExpression(node.moduleSpecifier);
+            writeSemicolon();
+        }
+        function emitImportClause(node) {
+            emit(node.name);
+            if (node.name && node.namedBindings) {
+                emitTokenWithComment(26 /* CommaToken */, node.name.end, writePunctuation, node);
+                writeSpace();
+            }
+            emit(node.namedBindings);
+        }
+        function emitNamespaceImport(node) {
+            var asPos = emitTokenWithComment(39 /* AsteriskToken */, node.pos, writePunctuation, node);
+            writeSpace();
+            emitTokenWithComment(118 /* AsKeyword */, asPos, writeKeyword, node);
+            writeSpace();
+            emit(node.name);
+        }
+        function emitNamedImports(node) {
+            emitNamedImportsOrExports(node);
+        }
+        function emitImportSpecifier(node) {
+            emitImportOrExportSpecifier(node);
+        }
+        function emitExportAssignment(node) {
+            var nextPos = emitTokenWithComment(84 /* ExportKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            if (node.isExportEquals) {
+                emitTokenWithComment(58 /* EqualsToken */, nextPos, writeOperator, node);
+            }
+            else {
+                emitTokenWithComment(79 /* DefaultKeyword */, nextPos, writeKeyword, node);
+            }
+            writeSpace();
+            emitExpression(node.expression);
+            writeSemicolon();
+        }
+        function emitExportDeclaration(node) {
+            var nextPos = emitTokenWithComment(84 /* ExportKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            if (node.exportClause) {
+                emit(node.exportClause);
+            }
+            else {
+                nextPos = emitTokenWithComment(39 /* AsteriskToken */, nextPos, writePunctuation, node);
+            }
+            if (node.moduleSpecifier) {
+                writeSpace();
+                var fromPos = node.exportClause ? node.exportClause.end : nextPos;
+                emitTokenWithComment(143 /* FromKeyword */, fromPos, writeKeyword, node);
+                writeSpace();
+                emitExpression(node.moduleSpecifier);
+            }
+            writeSemicolon();
+        }
+        function emitNamespaceExportDeclaration(node) {
+            var nextPos = emitTokenWithComment(84 /* ExportKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            nextPos = emitTokenWithComment(118 /* AsKeyword */, nextPos, writeKeyword, node);
+            writeSpace();
+            nextPos = emitTokenWithComment(130 /* NamespaceKeyword */, nextPos, writeKeyword, node);
+            writeSpace();
+            emit(node.name);
+            writeSemicolon();
+        }
+        function emitNamedExports(node) {
+            emitNamedImportsOrExports(node);
+        }
+        function emitExportSpecifier(node) {
+            emitImportOrExportSpecifier(node);
+        }
+        function emitNamedImportsOrExports(node) {
+            writePunctuation("{");
+            emitList(node, node.elements, 262576 /* NamedImportsOrExportsElements */);
+            writePunctuation("}");
+        }
+        function emitImportOrExportSpecifier(node) {
+            if (node.propertyName) {
+                emit(node.propertyName);
+                writeSpace();
+                emitTokenWithComment(118 /* AsKeyword */, node.propertyName.end, writeKeyword, node);
+                writeSpace();
+            }
+            emit(node.name);
+        }
+        //
+        // Module references
+        //
+        function emitExternalModuleReference(node) {
+            writeKeyword("require");
+            writePunctuation("(");
+            emitExpression(node.expression);
+            writePunctuation(")");
+        }
+        //
+        // JSX
+        //
+        function emitJsxElement(node) {
+            emit(node.openingElement);
+            emitList(node, node.children, 131072 /* JsxElementOrFragmentChildren */);
+            emit(node.closingElement);
+        }
+        function emitJsxSelfClosingElement(node) {
+            writePunctuation("<");
+            emitJsxTagName(node.tagName);
+            writeSpace();
+            emit(node.attributes);
+            writePunctuation("/>");
+        }
+        function emitJsxFragment(node) {
+            emit(node.openingFragment);
+            emitList(node, node.children, 131072 /* JsxElementOrFragmentChildren */);
+            emit(node.closingFragment);
+        }
+        function emitJsxOpeningElementOrFragment(node) {
+            writePunctuation("<");
+            if (ts.isJsxOpeningElement(node)) {
+                emitJsxTagName(node.tagName);
+                if (node.attributes.properties && node.attributes.properties.length > 0) {
+                    writeSpace();
+                }
+                emit(node.attributes);
+            }
+            writePunctuation(">");
+        }
+        function emitJsxText(node) {
+            commitPendingSemicolon();
+            writer.writeLiteral(getTextOfNode(node, /*includeTrivia*/ true));
+        }
+        function emitJsxClosingElementOrFragment(node) {
+            writePunctuation("</");
+            if (ts.isJsxClosingElement(node)) {
+                emitJsxTagName(node.tagName);
+            }
+            writePunctuation(">");
+        }
+        function emitJsxAttributes(node) {
+            emitList(node, node.properties, 131328 /* JsxElementAttributes */);
+        }
+        function emitJsxAttribute(node) {
+            emit(node.name);
+            emitNodeWithPrefix("=", writePunctuation, node.initializer, emit); // TODO: GH#18217
+        }
+        function emitJsxSpreadAttribute(node) {
+            writePunctuation("{...");
+            emitExpression(node.expression);
+            writePunctuation("}");
+        }
+        function emitJsxExpression(node) {
+            if (node.expression) {
+                writePunctuation("{");
+                emit(node.dotDotDotToken);
+                emitExpression(node.expression);
+                writePunctuation("}");
+            }
+        }
+        function emitJsxTagName(node) {
+            if (node.kind === 71 /* Identifier */) {
+                emitExpression(node);
+            }
+            else {
+                emit(node);
+            }
+        }
+        //
+        // Clauses
+        //
+        function emitCaseClause(node) {
+            emitTokenWithComment(73 /* CaseKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            emitExpression(node.expression);
+            emitCaseOrDefaultClauseRest(node, node.statements, node.expression.end);
+        }
+        function emitDefaultClause(node) {
+            var pos = emitTokenWithComment(79 /* DefaultKeyword */, node.pos, writeKeyword, node);
+            emitCaseOrDefaultClauseRest(node, node.statements, pos);
+        }
+        function emitCaseOrDefaultClauseRest(parentNode, statements, colonPos) {
+            var emitAsSingleStatement = statements.length === 1 &&
+                (
+                // treat synthesized nodes as located on the same line for emit purposes
+                ts.nodeIsSynthesized(parentNode) ||
+                    ts.nodeIsSynthesized(statements[0]) ||
+                    ts.rangeStartPositionsAreOnSameLine(parentNode, statements[0], currentSourceFile));
+            var format = 81985 /* CaseOrDefaultClauseStatements */;
+            if (emitAsSingleStatement) {
+                writeToken(56 /* ColonToken */, colonPos, writePunctuation, parentNode);
+                writeSpace();
+                format &= ~(1 /* MultiLine */ | 64 /* Indented */);
+            }
+            else {
+                emitTokenWithComment(56 /* ColonToken */, colonPos, writePunctuation, parentNode);
+            }
+            emitList(parentNode, statements, format);
+        }
+        function emitHeritageClause(node) {
+            writeSpace();
+            writeTokenText(node.token, writeKeyword);
+            writeSpace();
+            emitList(node, node.types, 272 /* HeritageClauseTypes */);
+        }
+        function emitCatchClause(node) {
+            var openParenPos = emitTokenWithComment(74 /* CatchKeyword */, node.pos, writeKeyword, node);
+            writeSpace();
+            if (node.variableDeclaration) {
+                emitTokenWithComment(19 /* OpenParenToken */, openParenPos, writePunctuation, node);
+                emit(node.variableDeclaration);
+                emitTokenWithComment(20 /* CloseParenToken */, node.variableDeclaration.end, writePunctuation, node);
+                writeSpace();
+            }
+            emit(node.block);
+        }
+        //
+        // Property assignments
+        //
+        function emitPropertyAssignment(node) {
+            emit(node.name);
+            writePunctuation(":");
+            writeSpace();
+            // This is to ensure that we emit comment in the following case:
+            //      For example:
+            //          obj = {
+            //              id: /*comment1*/ ()=>void
+            //          }
+            // "comment1" is not considered to be leading comment for node.initializer
+            // but rather a trailing comment on the previous node.
+            var initializer = node.initializer;
+            if (emitTrailingCommentsOfPosition && (ts.getEmitFlags(initializer) & 512 /* NoLeadingComments */) === 0) {
+                var commentRange = ts.getCommentRange(initializer);
+                emitTrailingCommentsOfPosition(commentRange.pos);
+            }
+            emitExpression(initializer);
+        }
+        function emitShorthandPropertyAssignment(node) {
+            emit(node.name);
+            if (node.objectAssignmentInitializer) {
+                writeSpace();
+                writePunctuation("=");
+                writeSpace();
+                emitExpression(node.objectAssignmentInitializer);
+            }
+        }
+        function emitSpreadAssignment(node) {
+            if (node.expression) {
+                writePunctuation("...");
+                emitExpression(node.expression);
+            }
+        }
+        //
+        // Enum
+        //
+        function emitEnumMember(node) {
+            emit(node.name);
+            emitInitializer(node.initializer, node.name.end, node);
+        }
+        //
+        // Top-level nodes
+        //
+        function emitSourceFile(node) {
+            writeLine();
+            var statements = node.statements;
+            if (emitBodyWithDetachedComments) {
+                // Emit detached comment if there are no prologue directives or if the first node is synthesized.
+                // The synthesized node will have no leading comment so some comments may be missed.
+                var shouldEmitDetachedComment = statements.length === 0 ||
+                    !ts.isPrologueDirective(statements[0]) ||
+                    ts.nodeIsSynthesized(statements[0]);
+                if (shouldEmitDetachedComment) {
+                    emitBodyWithDetachedComments(node, statements, emitSourceFileWorker);
+                    return;
+                }
+            }
+            emitSourceFileWorker(node);
+        }
+        function emitSyntheticTripleSlashReferencesIfNeeded(node) {
+            emitTripleSlashDirectives(!!node.hasNoDefaultLib, node.syntheticFileReferences || [], node.syntheticTypeReferences || []);
+        }
+        function emitTripleSlashDirectivesIfNeeded(node) {
+            if (node.isDeclarationFile)
+                emitTripleSlashDirectives(node.hasNoDefaultLib, node.referencedFiles, node.typeReferenceDirectives);
+        }
+        function emitTripleSlashDirectives(hasNoDefaultLib, files, types) {
+            if (hasNoDefaultLib) {
+                write("/// <reference no-default-lib=\"true\"/>");
+                writeLine();
+            }
+            if (currentSourceFile && currentSourceFile.moduleName) {
+                write("/// <amd-module name=\"" + currentSourceFile.moduleName + "\" />");
+                writeLine();
+            }
+            if (currentSourceFile && currentSourceFile.amdDependencies) {
+                for (var _a = 0, _b = currentSourceFile.amdDependencies; _a < _b.length; _a++) {
+                    var dep = _b[_a];
+                    if (dep.name) {
+                        write("/// <amd-dependency name=\"" + dep.name + "\" path=\"" + dep.path + "\" />");
+                    }
+                    else {
+                        write("/// <amd-dependency path=\"" + dep.path + "\" />");
+                    }
+                    writeLine();
+                }
+            }
+            for (var _c = 0, files_1 = files; _c < files_1.length; _c++) {
+                var directive = files_1[_c];
+                write("/// <reference path=\"" + directive.fileName + "\" />");
+                writeLine();
+            }
+            for (var _d = 0, types_17 = types; _d < types_17.length; _d++) {
+                var directive = types_17[_d];
+                write("/// <reference types=\"" + directive.fileName + "\" />");
+                writeLine();
+            }
+        }
+        function emitSourceFileWorker(node) {
+            var statements = node.statements;
+            pushNameGenerationScope(node);
+            ts.forEach(node.statements, generateNames);
+            emitHelpers(node);
+            var index = ts.findIndex(statements, function (statement) { return !ts.isPrologueDirective(statement); });
+            emitTripleSlashDirectivesIfNeeded(node);
+            emitList(node, statements, 1 /* MultiLine */, index === -1 ? statements.length : index);
+            popNameGenerationScope(node);
+        }
+        // Transformation nodes
+        function emitPartiallyEmittedExpression(node) {
+            emitExpression(node.expression);
+        }
+        function emitCommaList(node) {
+            emitExpressionList(node, node.elements, 272 /* CommaListElements */);
+        }
+        /**
+         * Emits any prologue directives at the start of a Statement list, returning the
+         * number of prologue directives written to the output.
+         */
+        function emitPrologueDirectives(statements, startWithNewLine, seenPrologueDirectives) {
+            for (var i = 0; i < statements.length; i++) {
+                var statement = statements[i];
+                if (ts.isPrologueDirective(statement)) {
+                    var shouldEmitPrologueDirective = seenPrologueDirectives ? !seenPrologueDirectives.has(statement.expression.text) : true;
+                    if (shouldEmitPrologueDirective) {
+                        if (startWithNewLine || i > 0) {
+                            writeLine();
+                        }
+                        emit(statement);
+                        if (seenPrologueDirectives) {
+                            seenPrologueDirectives.set(statement.expression.text, true);
+                        }
+                    }
+                }
+                else {
+                    // return index of the first non prologue directive
+                    return i;
+                }
+            }
+            return statements.length;
+        }
+        function emitPrologueDirectivesIfNeeded(sourceFileOrBundle) {
+            if (ts.isSourceFile(sourceFileOrBundle)) {
+                setSourceFile(sourceFileOrBundle);
+                emitPrologueDirectives(sourceFileOrBundle.statements);
+            }
+            else {
+                var seenPrologueDirectives = ts.createMap();
+                for (var _a = 0, _b = sourceFileOrBundle.sourceFiles; _a < _b.length; _a++) {
+                    var sourceFile = _b[_a];
+                    setSourceFile(sourceFile);
+                    emitPrologueDirectives(sourceFile.statements, /*startWithNewLine*/ true, seenPrologueDirectives);
+                }
+            }
+        }
+        function emitShebangIfNeeded(sourceFileOrBundle) {
+            if (ts.isSourceFile(sourceFileOrBundle)) {
+                var shebang = ts.getShebang(sourceFileOrBundle.text);
+                if (shebang) {
+                    write(shebang);
+                    writeLine();
+                    return true;
+                }
+            }
+            else {
+                for (var _a = 0, _b = sourceFileOrBundle.sourceFiles; _a < _b.length; _a++) {
+                    var sourceFile = _b[_a];
+                    // Emit only the first encountered shebang
+                    if (emitShebangIfNeeded(sourceFile)) {
+                        break;
+                    }
+                }
+            }
+        }
+        //
+        // Helpers
+        //
+        function emitNodeWithWriter(node, writer) {
+            if (!node)
+                return;
+            var savedWrite = write;
+            write = writer;
+            emit(node);
+            write = savedWrite;
+        }
+        function emitModifiers(node, modifiers) {
+            if (modifiers && modifiers.length) {
+                emitList(node, modifiers, 131328 /* Modifiers */);
+                writeSpace();
+            }
+        }
+        function emitTypeAnnotation(node) {
+            if (node) {
+                writePunctuation(":");
+                writeSpace();
+                emit(node);
+            }
+        }
+        function emitInitializer(node, equalCommentStartPos, container) {
+            if (node) {
+                writeSpace();
+                emitTokenWithComment(58 /* EqualsToken */, equalCommentStartPos, writeOperator, container);
+                writeSpace();
+                emitExpression(node);
+            }
+        }
+        function emitNodeWithPrefix(prefix, prefixWriter, node, emit) {
+            if (node) {
+                prefixWriter(prefix);
+                emit(node);
+            }
+        }
+        function emitWithLeadingSpace(node) {
+            if (node) {
+                writeSpace();
+                emit(node);
+            }
+        }
+        function emitExpressionWithLeadingSpace(node) {
+            if (node) {
+                writeSpace();
+                emitExpression(node);
+            }
+        }
+        function emitWithTrailingSpace(node) {
+            if (node) {
+                emit(node);
+                writeSpace();
+            }
+        }
+        function emitEmbeddedStatement(parent, node) {
+            if (ts.isBlock(node) || ts.getEmitFlags(parent) & 1 /* SingleLine */) {
+                writeSpace();
+                emit(node);
+            }
+            else {
+                writeLine();
+                increaseIndent();
+                emit(node);
+                decreaseIndent();
+            }
+        }
+        function emitDecorators(parentNode, decorators) {
+            emitList(parentNode, decorators, 24577 /* Decorators */);
+        }
+        function emitTypeArguments(parentNode, typeArguments) {
+            emitList(parentNode, typeArguments, 26896 /* TypeArguments */);
+        }
+        function emitTypeParameters(parentNode, typeParameters) {
+            if (ts.isFunctionLike(parentNode) && parentNode.typeArguments) { // Quick info uses type arguments in place of type parameters on instantiated signatures
+                return emitTypeArguments(parentNode, parentNode.typeArguments);
+            }
+            emitList(parentNode, typeParameters, 26896 /* TypeParameters */);
+        }
+        function emitParameters(parentNode, parameters) {
+            emitList(parentNode, parameters, 1296 /* Parameters */);
+        }
+        function canEmitSimpleArrowHead(parentNode, parameters) {
+            var parameter = ts.singleOrUndefined(parameters);
+            return parameter
+                && parameter.pos === parentNode.pos // may not have parsed tokens between parent and parameter
+                && !(ts.isArrowFunction(parentNode) && parentNode.type) // arrow function may not have return type annotation
+                && !ts.some(parentNode.decorators) // parent may not have decorators
+                && !ts.some(parentNode.modifiers) // parent may not have modifiers
+                && !ts.some(parentNode.typeParameters) // parent may not have type parameters
+                && !ts.some(parameter.decorators) // parameter may not have decorators
+                && !ts.some(parameter.modifiers) // parameter may not have modifiers
+                && !parameter.dotDotDotToken // parameter may not be rest
+                && !parameter.questionToken // parameter may not be optional
+                && !parameter.type // parameter may not have a type annotation
+                && !parameter.initializer // parameter may not have an initializer
+                && ts.isIdentifier(parameter.name); // parameter name must be identifier
+        }
+        function emitParametersForArrow(parentNode, parameters) {
+            if (canEmitSimpleArrowHead(parentNode, parameters)) {
+                emitList(parentNode, parameters, 1296 /* Parameters */ & ~1024 /* Parenthesis */);
+            }
+            else {
+                emitParameters(parentNode, parameters);
+            }
+        }
+        function emitParametersForIndexSignature(parentNode, parameters) {
+            emitList(parentNode, parameters, 4432 /* IndexSignatureParameters */);
+        }
+        function emitList(parentNode, children, format, start, count) {
+            emitNodeList(emit, parentNode, children, format, start, count);
+        }
+        function emitExpressionList(parentNode, children, format, start, count) {
+            emitNodeList(emitExpression, parentNode, children, format, start, count); // TODO: GH#18217
+        }
+        function writeDelimiter(format) {
+            switch (format & 28 /* DelimitersMask */) {
+                case 0 /* None */:
+                    break;
+                case 16 /* CommaDelimited */:
+                    writePunctuation(",");
+                    break;
+                case 4 /* BarDelimited */:
+                    writeSpace();
+                    writePunctuation("|");
+                    break;
+                case 8 /* AmpersandDelimited */:
+                    writeSpace();
+                    writePunctuation("&");
+                    break;
+            }
+        }
+        function emitNodeList(emit, parentNode, children, format, start, count) {
+            if (start === void 0) { start = 0; }
+            if (count === void 0) { count = children ? children.length - start : 0; }
+            var isUndefined = children === undefined;
+            if (isUndefined && format & 8192 /* OptionalIfUndefined */) {
+                return;
+            }
+            var isEmpty = children === undefined || start >= children.length || count === 0;
+            if (isEmpty && format & 16384 /* OptionalIfEmpty */) {
+                if (onBeforeEmitNodeArray) {
+                    onBeforeEmitNodeArray(children);
+                }
+                if (onAfterEmitNodeArray) {
+                    onAfterEmitNodeArray(children);
+                }
+                return;
+            }
+            if (format & 7680 /* BracketsMask */) {
+                writePunctuation(getOpeningBracket(format));
+                if (isEmpty && !isUndefined) {
+                    // TODO: GH#18217
+                    emitTrailingCommentsOfPosition(children.pos, /*prefixSpace*/ true); // Emit comments within empty bracketed lists
+                }
+            }
+            if (onBeforeEmitNodeArray) {
+                onBeforeEmitNodeArray(children);
+            }
+            if (isEmpty) {
+                // Write a line terminator if the parent node was multi-line
+                if (format & 1 /* MultiLine */) {
+                    writeLine();
+                }
+                else if (format & 128 /* SpaceBetweenBraces */ && !(format & 262144 /* NoSpaceIfEmpty */)) {
+                    writeSpace();
+                }
+            }
+            else {
+                // Write the opening line terminator or leading whitespace.
+                var mayEmitInterveningComments = (format & 131072 /* NoInterveningComments */) === 0;
+                var shouldEmitInterveningComments = mayEmitInterveningComments;
+                if (shouldWriteLeadingLineTerminator(parentNode, children, format)) { // TODO: GH#18217
+                    writeLine();
+                    shouldEmitInterveningComments = false;
+                }
+                else if (format & 128 /* SpaceBetweenBraces */) {
+                    writeSpace();
+                }
+                // Increase the indent, if requested.
+                if (format & 64 /* Indented */) {
+                    increaseIndent();
+                }
+                // Emit each child.
+                var previousSibling = void 0;
+                var shouldDecreaseIndentAfterEmit = false;
+                for (var i = 0; i < count; i++) {
+                    var child = children[start + i];
+                    // Write the delimiter if this is not the first node.
+                    if (previousSibling) {
+                        // i.e
+                        //      function commentedParameters(
+                        //          /* Parameter a */
+                        //          a
+                        //          /* End of parameter a */ -> this comment isn't considered to be trailing comment of parameter "a" due to newline
+                        //          ,
+                        if (format & 28 /* DelimitersMask */ && previousSibling.end !== parentNode.end) {
+                            emitLeadingCommentsOfPosition(previousSibling.end);
+                        }
+                        writeDelimiter(format);
+                        // Write either a line terminator or whitespace to separate the elements.
+                        if (shouldWriteSeparatingLineTerminator(previousSibling, child, format)) {
+                            // If a synthesized node in a single-line list starts on a new
+                            // line, we should increase the indent.
+                            if ((format & (3 /* LinesMask */ | 64 /* Indented */)) === 0 /* SingleLine */) {
+                                increaseIndent();
+                                shouldDecreaseIndentAfterEmit = true;
+                            }
+                            writeLine();
+                            shouldEmitInterveningComments = false;
+                        }
+                        else if (previousSibling && format & 256 /* SpaceBetweenSiblings */) {
+                            writeSpace();
+                        }
+                    }
+                    // Emit this child.
+                    if (shouldEmitInterveningComments) {
+                        if (emitTrailingCommentsOfPosition) {
+                            var commentRange = ts.getCommentRange(child);
+                            emitTrailingCommentsOfPosition(commentRange.pos);
+                        }
+                    }
+                    else {
+                        shouldEmitInterveningComments = mayEmitInterveningComments;
+                    }
+                    emit(child);
+                    if (shouldDecreaseIndentAfterEmit) {
+                        decreaseIndent();
+                        shouldDecreaseIndentAfterEmit = false;
+                    }
+                    previousSibling = child;
+                }
+                // Write a trailing comma, if requested.
+                var hasTrailingComma = (format & 32 /* AllowTrailingComma */) && children.hasTrailingComma;
+                if (format & 16 /* CommaDelimited */ && hasTrailingComma) {
+                    writePunctuation(",");
+                }
+                // Emit any trailing comment of the last element in the list
+                // i.e
+                //       var array = [...
+                //          2
+                //          /* end of element 2 */
+                //       ];
+                if (previousSibling && format & 28 /* DelimitersMask */ && previousSibling.end !== parentNode.end && !(ts.getEmitFlags(previousSibling) & 1024 /* NoTrailingComments */)) {
+                    emitLeadingCommentsOfPosition(previousSibling.end);
+                }
+                // Decrease the indent, if requested.
+                if (format & 64 /* Indented */) {
+                    decreaseIndent();
+                }
+                // Write the closing line terminator or closing whitespace.
+                if (shouldWriteClosingLineTerminator(parentNode, children, format)) {
+                    writeLine();
+                }
+                else if (format & 128 /* SpaceBetweenBraces */) {
+                    writeSpace();
+                }
+            }
+            if (onAfterEmitNodeArray) {
+                onAfterEmitNodeArray(children);
+            }
+            if (format & 7680 /* BracketsMask */) {
+                if (isEmpty && !isUndefined) {
+                    // TODO: GH#18217
+                    emitLeadingCommentsOfPosition(children.end); // Emit leading comments within empty lists
+                }
+                writePunctuation(getClosingBracket(format));
+            }
+        }
+        function commitPendingSemicolonInternal() {
+            if (pendingSemicolon) {
+                writeSemicolonInternal();
+                pendingSemicolon = false;
+            }
+        }
+        function writeLiteral(s) {
+            commitPendingSemicolon();
+            writer.writeLiteral(s);
+        }
+        function writeStringLiteral(s) {
+            commitPendingSemicolon();
+            writer.writeStringLiteral(s);
+        }
+        function writeBase(s) {
+            commitPendingSemicolon();
+            writer.write(s);
+        }
+        function writeSymbol(s, sym) {
+            commitPendingSemicolon();
+            writer.writeSymbol(s, sym);
+        }
+        function writePunctuation(s) {
+            commitPendingSemicolon();
+            writer.writePunctuation(s);
+        }
+        function deferWriteSemicolon() {
+            pendingSemicolon = true;
+        }
+        function writeSemicolonInternal() {
+            writer.writePunctuation(";");
+        }
+        function writeKeyword(s) {
+            commitPendingSemicolon();
+            writer.writeKeyword(s);
+        }
+        function writeOperator(s) {
+            commitPendingSemicolon();
+            writer.writeOperator(s);
+        }
+        function writeParameter(s) {
+            commitPendingSemicolon();
+            writer.writeParameter(s);
+        }
+        function writeSpace() {
+            commitPendingSemicolon();
+            writer.writeSpace(" ");
+        }
+        function writeProperty(s) {
+            commitPendingSemicolon();
+            writer.writeProperty(s);
+        }
+        function writeLine() {
+            commitPendingSemicolon();
+            writer.writeLine();
+        }
+        function increaseIndent() {
+            commitPendingSemicolon();
+            writer.increaseIndent();
+        }
+        function decreaseIndent() {
+            commitPendingSemicolon();
+            writer.decreaseIndent();
+        }
+        function writeToken(token, pos, writer, contextNode) {
+            return onEmitSourceMapOfToken
+                ? onEmitSourceMapOfToken(contextNode, token, writer, pos, writeTokenText)
+                : writeTokenText(token, writer, pos);
+        }
+        function writeTokenNode(node, writer) {
+            if (onBeforeEmitToken) {
+                onBeforeEmitToken(node);
+            }
+            writer(ts.tokenToString(node.kind));
+            if (onAfterEmitToken) {
+                onAfterEmitToken(node);
+            }
+        }
+        function writeTokenText(token, writer, pos) {
+            var tokenString = ts.tokenToString(token);
+            writer(tokenString);
+            return pos < 0 ? pos : pos + tokenString.length;
+        }
+        function writeLineOrSpace(node) {
+            if (ts.getEmitFlags(node) & 1 /* SingleLine */) {
+                writeSpace();
+            }
+            else {
+                writeLine();
+            }
+        }
+        function writeLines(text) {
+            var lines = text.split(/\r\n?|\n/g);
+            var indentation = ts.guessIndentation(lines);
+            for (var _a = 0, lines_2 = lines; _a < lines_2.length; _a++) {
+                var lineText = lines_2[_a];
+                var line = indentation ? lineText.slice(indentation) : lineText;
+                if (line.length) {
+                    writeLine();
+                    write(line);
+                    writeLine();
+                }
+            }
+        }
+        function increaseIndentIf(value, valueToWriteWhenNotIndenting) {
+            if (value) {
+                increaseIndent();
+                writeLine();
+            }
+            else if (valueToWriteWhenNotIndenting) {
+                write(valueToWriteWhenNotIndenting);
+            }
+        }
+        // Helper function to decrease the indent if we previously indented.  Allows multiple
+        // previous indent values to be considered at a time.  This also allows caller to just
+        // call this once, passing in all their appropriate indent values, instead of needing
+        // to call this helper function multiple times.
+        function decreaseIndentIf(value1, value2) {
+            if (value1) {
+                decreaseIndent();
+            }
+            if (value2) {
+                decreaseIndent();
+            }
+        }
+        function shouldWriteLeadingLineTerminator(parentNode, children, format) {
+            if (format & 1 /* MultiLine */) {
+                return true;
+            }
+            if (format & 2 /* PreserveLines */) {
+                if (format & 32768 /* PreferNewLine */) {
+                    return true;
+                }
+                var firstChild = children[0];
+                if (firstChild === undefined) {
+                    return !ts.rangeIsOnSingleLine(parentNode, currentSourceFile);
+                }
+                else if (ts.positionIsSynthesized(parentNode.pos) || ts.nodeIsSynthesized(firstChild)) {
+                    return synthesizedNodeStartsOnNewLine(firstChild, format);
+                }
+                else {
+                    return !ts.rangeStartPositionsAreOnSameLine(parentNode, firstChild, currentSourceFile);
+                }
+            }
+            else {
+                return false;
+            }
+        }
+        function shouldWriteSeparatingLineTerminator(previousNode, nextNode, format) {
+            if (format & 1 /* MultiLine */) {
+                return true;
+            }
+            else if (format & 2 /* PreserveLines */) {
+                if (previousNode === undefined || nextNode === undefined) {
+                    return false;
+                }
+                else if (ts.nodeIsSynthesized(previousNode) || ts.nodeIsSynthesized(nextNode)) {
+                    return synthesizedNodeStartsOnNewLine(previousNode, format) || synthesizedNodeStartsOnNewLine(nextNode, format);
+                }
+                else {
+                    return !ts.rangeEndIsOnSameLineAsRangeStart(previousNode, nextNode, currentSourceFile);
+                }
+            }
+            else {
+                return ts.getStartsOnNewLine(nextNode);
+            }
+        }
+        function shouldWriteClosingLineTerminator(parentNode, children, format) {
+            if (format & 1 /* MultiLine */) {
+                return (format & 65536 /* NoTrailingNewLine */) === 0;
+            }
+            else if (format & 2 /* PreserveLines */) {
+                if (format & 32768 /* PreferNewLine */) {
+                    return true;
+                }
+                var lastChild = ts.lastOrUndefined(children);
+                if (lastChild === undefined) {
+                    return !ts.rangeIsOnSingleLine(parentNode, currentSourceFile);
+                }
+                else if (ts.positionIsSynthesized(parentNode.pos) || ts.nodeIsSynthesized(lastChild)) {
+                    return synthesizedNodeStartsOnNewLine(lastChild, format);
+                }
+                else {
+                    return !ts.rangeEndPositionsAreOnSameLine(parentNode, lastChild, currentSourceFile);
+                }
+            }
+            else {
+                return false;
+            }
+        }
+        function synthesizedNodeStartsOnNewLine(node, format) {
+            if (ts.nodeIsSynthesized(node)) {
+                var startsOnNewLine = ts.getStartsOnNewLine(node);
+                if (startsOnNewLine === undefined) {
+                    return (format & 32768 /* PreferNewLine */) !== 0;
+                }
+                return startsOnNewLine;
+            }
+            return (format & 32768 /* PreferNewLine */) !== 0;
+        }
+        function needsIndentation(parent, node1, node2) {
+            parent = skipSynthesizedParentheses(parent);
+            node1 = skipSynthesizedParentheses(node1);
+            node2 = skipSynthesizedParentheses(node2);
+            // Always use a newline for synthesized code if the synthesizer desires it.
+            if (ts.getStartsOnNewLine(node2)) {
+                return true;
+            }
+            return !ts.nodeIsSynthesized(parent)
+                && !ts.nodeIsSynthesized(node1)
+                && !ts.nodeIsSynthesized(node2)
+                && !ts.rangeEndIsOnSameLineAsRangeStart(node1, node2, currentSourceFile);
+        }
+        function isEmptyBlock(block) {
+            return block.statements.length === 0
+                && ts.rangeEndIsOnSameLineAsRangeStart(block, block, currentSourceFile);
+        }
+        function skipSynthesizedParentheses(node) {
+            while (node.kind === 191 /* ParenthesizedExpression */ && ts.nodeIsSynthesized(node)) {
+                node = node.expression;
+            }
+            return node;
+        }
+        function getTextOfNode(node, includeTrivia) {
+            if (ts.isGeneratedIdentifier(node)) {
+                return generateName(node);
+            }
+            else if (ts.isIdentifier(node) && (ts.nodeIsSynthesized(node) || !node.parent || !currentSourceFile || (node.parent && currentSourceFile && ts.getSourceFileOfNode(node) !== ts.getOriginalNode(currentSourceFile)))) {
+                return ts.idText(node);
+            }
+            else if (node.kind === 9 /* StringLiteral */ && node.textSourceNode) {
+                return getTextOfNode(node.textSourceNode, includeTrivia);
+            }
+            else if (ts.isLiteralExpression(node) && (ts.nodeIsSynthesized(node) || !node.parent)) {
+                return node.text;
+            }
+            return ts.getSourceTextOfNodeFromSourceFile(currentSourceFile, node, includeTrivia);
+        }
+        function getLiteralTextOfNode(node) {
+            if (node.kind === 9 /* StringLiteral */ && node.textSourceNode) {
+                var textSourceNode = node.textSourceNode;
+                if (ts.isIdentifier(textSourceNode)) {
+                    return ts.getEmitFlags(node) & 16777216 /* NoAsciiEscaping */ ?
+                        "\"" + ts.escapeString(getTextOfNode(textSourceNode)) + "\"" :
+                        "\"" + ts.escapeNonAsciiString(getTextOfNode(textSourceNode)) + "\"";
+                }
+                else {
+                    return getLiteralTextOfNode(textSourceNode);
+                }
+            }
+            return ts.getLiteralText(node, currentSourceFile);
+        }
+        /**
+         * Push a new name generation scope.
+         */
+        function pushNameGenerationScope(node) {
+            if (node && ts.getEmitFlags(node) & 524288 /* ReuseTempVariableScope */) {
+                return;
+            }
+            tempFlagsStack.push(tempFlags);
+            tempFlags = 0;
+            reservedNamesStack.push(reservedNames);
+        }
+        /**
+         * Pop the current name generation scope.
+         */
+        function popNameGenerationScope(node) {
+            if (node && ts.getEmitFlags(node) & 524288 /* ReuseTempVariableScope */) {
+                return;
+            }
+            tempFlags = tempFlagsStack.pop();
+            reservedNames = reservedNamesStack.pop();
+        }
+        function reserveNameInNestedScopes(name) {
+            if (!reservedNames || reservedNames === ts.lastOrUndefined(reservedNamesStack)) {
+                reservedNames = ts.createMap();
+            }
+            reservedNames.set(name, true);
+        }
+        function generateNames(node) {
+            if (!node)
+                return;
+            switch (node.kind) {
+                case 213 /* Block */:
+                    ts.forEach(node.statements, generateNames);
+                    break;
+                case 228 /* LabeledStatement */:
+                case 226 /* WithStatement */:
+                case 218 /* DoStatement */:
+                case 219 /* WhileStatement */:
+                    generateNames(node.statement);
+                    break;
+                case 217 /* IfStatement */:
+                    generateNames(node.thenStatement);
+                    generateNames(node.elseStatement);
+                    break;
+                case 220 /* ForStatement */:
+                case 222 /* ForOfStatement */:
+                case 221 /* ForInStatement */:
+                    generateNames(node.initializer);
+                    generateNames(node.statement);
+                    break;
+                case 227 /* SwitchStatement */:
+                    generateNames(node.caseBlock);
+                    break;
+                case 241 /* CaseBlock */:
+                    ts.forEach(node.clauses, generateNames);
+                    break;
+                case 266 /* CaseClause */:
+                case 267 /* DefaultClause */:
+                    ts.forEach(node.statements, generateNames);
+                    break;
+                case 230 /* TryStatement */:
+                    generateNames(node.tryBlock);
+                    generateNames(node.catchClause);
+                    generateNames(node.finallyBlock);
+                    break;
+                case 269 /* CatchClause */:
+                    generateNames(node.variableDeclaration);
+                    generateNames(node.block);
+                    break;
+                case 214 /* VariableStatement */:
+                    generateNames(node.declarationList);
+                    break;
+                case 233 /* VariableDeclarationList */:
+                    ts.forEach(node.declarations, generateNames);
+                    break;
+                case 232 /* VariableDeclaration */:
+                case 149 /* Parameter */:
+                case 182 /* BindingElement */:
+                case 235 /* ClassDeclaration */:
+                    generateNameIfNeeded(node.name);
+                    break;
+                case 234 /* FunctionDeclaration */:
+                    generateNameIfNeeded(node.name);
+                    if (ts.getEmitFlags(node) & 524288 /* ReuseTempVariableScope */) {
+                        ts.forEach(node.parameters, generateNames);
+                        generateNames(node.body);
+                    }
+                    break;
+                case 180 /* ObjectBindingPattern */:
+                case 181 /* ArrayBindingPattern */:
+                    ts.forEach(node.elements, generateNames);
+                    break;
+                case 244 /* ImportDeclaration */:
+                    generateNames(node.importClause);
+                    break;
+                case 245 /* ImportClause */:
+                    generateNameIfNeeded(node.name);
+                    generateNames(node.namedBindings);
+                    break;
+                case 246 /* NamespaceImport */:
+                    generateNameIfNeeded(node.name);
+                    break;
+                case 247 /* NamedImports */:
+                    ts.forEach(node.elements, generateNames);
+                    break;
+                case 248 /* ImportSpecifier */:
+                    generateNameIfNeeded(node.propertyName || node.name);
+                    break;
+            }
+        }
+        function generateMemberNames(node) {
+            if (!node)
+                return;
+            switch (node.kind) {
+                case 270 /* PropertyAssignment */:
+                case 271 /* ShorthandPropertyAssignment */:
+                case 152 /* PropertyDeclaration */:
+                case 154 /* MethodDeclaration */:
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                    generateNameIfNeeded(node.name);
+                    break;
+            }
+        }
+        function generateNameIfNeeded(name) {
+            if (name) {
+                if (ts.isGeneratedIdentifier(name)) {
+                    generateName(name);
+                }
+                else if (ts.isBindingPattern(name)) {
+                    generateNames(name);
+                }
+            }
+        }
+        /**
+         * Generate the text for a generated identifier.
+         */
+        function generateName(name) {
+            if ((name.autoGenerateFlags & 7 /* KindMask */) === 4 /* Node */) {
+                // Node names generate unique names based on their original node
+                // and are cached based on that node's id.
+                return generateNameCached(getNodeForGeneratedName(name), name.autoGenerateFlags);
+            }
+            else {
+                // Auto, Loop, and Unique names are cached based on their unique
+                // autoGenerateId.
+                var autoGenerateId = name.autoGenerateId;
+                return autoGeneratedIdToGeneratedName[autoGenerateId] || (autoGeneratedIdToGeneratedName[autoGenerateId] = makeName(name));
+            }
+        }
+        function generateNameCached(node, flags) {
+            var nodeId = ts.getNodeId(node);
+            return nodeIdToGeneratedName[nodeId] || (nodeIdToGeneratedName[nodeId] = generateNameForNode(node, flags));
+        }
+        /**
+         * Returns a value indicating whether a name is unique globally, within the current file,
+         * or within the NameGenerator.
+         */
+        function isUniqueName(name) {
+            return isFileLevelUniqueName(name)
+                && !generatedNames.has(name)
+                && !(reservedNames && reservedNames.has(name));
+        }
+        /**
+         * Returns a value indicating whether a name is unique globally or within the current file.
+         */
+        function isFileLevelUniqueName(name) {
+            return currentSourceFile ? ts.isFileLevelUniqueName(currentSourceFile, name, hasGlobalName) : true;
+        }
+        /**
+         * Returns a value indicating whether a name is unique within a container.
+         */
+        function isUniqueLocalName(name, container) {
+            for (var node = container; ts.isNodeDescendantOf(node, container); node = node.nextContainer) {
+                if (node.locals) {
+                    var local = node.locals.get(ts.escapeLeadingUnderscores(name));
+                    // We conservatively include alias symbols to cover cases where they're emitted as locals
+                    if (local && local.flags & (67216319 /* Value */ | 1048576 /* ExportValue */ | 2097152 /* Alias */)) {
+                        return false;
+                    }
+                }
+            }
+            return true;
+        }
+        /**
+         * Return the next available name in the pattern _a ... _z, _0, _1, ...
+         * TempFlags._i or TempFlags._n may be used to express a preference for that dedicated name.
+         * Note that names generated by makeTempVariableName and makeUniqueName will never conflict.
+         */
+        function makeTempVariableName(flags, reservedInNestedScopes) {
+            if (flags && !(tempFlags & flags)) {
+                var name = flags === 268435456 /* _i */ ? "_i" : "_n";
+                if (isUniqueName(name)) {
+                    tempFlags |= flags;
+                    if (reservedInNestedScopes) {
+                        reserveNameInNestedScopes(name);
+                    }
+                    return name;
+                }
+            }
+            while (true) {
+                var count = tempFlags & 268435455 /* CountMask */;
+                tempFlags++;
+                // Skip over 'i' and 'n'
+                if (count !== 8 && count !== 13) {
+                    var name = count < 26
+                        ? "_" + String.fromCharCode(97 /* a */ + count)
+                        : "_" + (count - 26);
+                    if (isUniqueName(name)) {
+                        if (reservedInNestedScopes) {
+                            reserveNameInNestedScopes(name);
+                        }
+                        return name;
+                    }
+                }
+            }
+        }
+        /**
+         * Generate a name that is unique within the current file and doesn't conflict with any names
+         * in global scope. The name is formed by adding an '_n' suffix to the specified base name,
+         * where n is a positive integer. Note that names generated by makeTempVariableName and
+         * makeUniqueName are guaranteed to never conflict.
+         * If `optimistic` is set, the first instance will use 'baseName' verbatim instead of 'baseName_1'
+         */
+        function makeUniqueName(baseName, checkFn, optimistic, scoped) {
+            if (checkFn === void 0) { checkFn = isUniqueName; }
+            if (optimistic) {
+                if (checkFn(baseName)) {
+                    if (scoped) {
+                        reserveNameInNestedScopes(baseName);
+                    }
+                    else {
+                        generatedNames.set(baseName, true);
+                    }
+                    return baseName;
+                }
+            }
+            // Find the first unique 'name_n', where n is a positive number
+            if (baseName.charCodeAt(baseName.length - 1) !== 95 /* _ */) {
+                baseName += "_";
+            }
+            var i = 1;
+            while (true) {
+                var generatedName = baseName + i;
+                if (checkFn(generatedName)) {
+                    if (scoped) {
+                        reserveNameInNestedScopes(generatedName);
+                    }
+                    else {
+                        generatedNames.set(generatedName, true);
+                    }
+                    return generatedName;
+                }
+                i++;
+            }
+        }
+        function makeFileLevelOptmiisticUniqueName(name) {
+            return makeUniqueName(name, isFileLevelUniqueName, /*optimistic*/ true);
+        }
+        /**
+         * Generates a unique name for a ModuleDeclaration or EnumDeclaration.
+         */
+        function generateNameForModuleOrEnum(node) {
+            var name = getTextOfNode(node.name);
+            // Use module/enum name itself if it is unique, otherwise make a unique variation
+            return isUniqueLocalName(name, node) ? name : makeUniqueName(name);
+        }
+        /**
+         * Generates a unique name for an ImportDeclaration or ExportDeclaration.
+         */
+        function generateNameForImportOrExportDeclaration(node) {
+            var expr = ts.getExternalModuleName(node); // TODO: GH#18217
+            var baseName = ts.isStringLiteral(expr) ?
+                ts.makeIdentifierFromModuleName(expr.text) : "module";
+            return makeUniqueName(baseName);
+        }
+        /**
+         * Generates a unique name for a default export.
+         */
+        function generateNameForExportDefault() {
+            return makeUniqueName("default");
+        }
+        /**
+         * Generates a unique name for a class expression.
+         */
+        function generateNameForClassExpression() {
+            return makeUniqueName("class");
+        }
+        function generateNameForMethodOrAccessor(node) {
+            if (ts.isIdentifier(node.name)) {
+                return generateNameCached(node.name);
+            }
+            return makeTempVariableName(0 /* Auto */);
+        }
+        /**
+         * Generates a unique name from a node.
+         */
+        function generateNameForNode(node, flags) {
+            switch (node.kind) {
+                case 71 /* Identifier */:
+                    return makeUniqueName(getTextOfNode(node), isUniqueName, !!(flags & 16 /* Optimistic */), !!(flags & 8 /* ReservedInNestedScopes */));
+                case 239 /* ModuleDeclaration */:
+                case 238 /* EnumDeclaration */:
+                    return generateNameForModuleOrEnum(node);
+                case 244 /* ImportDeclaration */:
+                case 250 /* ExportDeclaration */:
+                    return generateNameForImportOrExportDeclaration(node);
+                case 234 /* FunctionDeclaration */:
+                case 235 /* ClassDeclaration */:
+                case 249 /* ExportAssignment */:
+                    return generateNameForExportDefault();
+                case 205 /* ClassExpression */:
+                    return generateNameForClassExpression();
+                case 154 /* MethodDeclaration */:
+                case 156 /* GetAccessor */:
+                case 157 /* SetAccessor */:
+                    return generateNameForMethodOrAccessor(node);
+                default:
+                    return makeTempVariableName(0 /* Auto */);
+            }
+        }
+        /**
+         * Generates a unique identifier for a node.
+         */
+        function makeName(name) {
+            switch (name.autoGenerateFlags & 7 /* KindMask */) {
+                case 1 /* Auto */:
+                    return makeTempVariableName(0 /* Auto */, !!(name.autoGenerateFlags & 8 /* ReservedInNestedScopes */));
+                case 2 /* Loop */:
+                    return makeTempVariableName(268435456 /* _i */, !!(name.autoGenerateFlags & 8 /* ReservedInNestedScopes */));
+                case 3 /* Unique */:
+                    return makeUniqueName(ts.idText(name), (name.autoGenerateFlags & 32 /* FileLevel */) ? isFileLevelUniqueName : isUniqueName, !!(name.autoGenerateFlags & 16 /* Optimistic */), !!(name.autoGenerateFlags & 8 /* ReservedInNestedScopes */));
+            }
+            return ts.Debug.fail("Unsupported GeneratedIdentifierKind.");
+        }
+        /**
+         * Gets the node from which a name should be generated.
+         */
+        function getNodeForGeneratedName(name) {
+            var autoGenerateId = name.autoGenerateId;
+            var node = name;
+            var original = node.original;
+            while (original) {
+                node = original;
+                // if "node" is a different generated name (having a different
+                // "autoGenerateId"), use it and stop traversing.
+                if (ts.isIdentifier(node)
+                    && !!(node.autoGenerateFlags & 4 /* Node */)
+                    && node.autoGenerateId !== autoGenerateId) {
+                    break;
+                }
+                original = node.original;
+            }
+            // otherwise, return the original node for the source;
+            return node;
+        }
+    }
+    ts.createPrinter = createPrinter;
+    function createBracketsMap() {
+        var brackets = [];
+        brackets[512 /* Braces */] = ["{", "}"];
+        brackets[1024 /* Parenthesis */] = ["(", ")"];
+        brackets[2048 /* AngleBrackets */] = ["<", ">"];
+        brackets[4096 /* SquareBrackets */] = ["[", "]"];
+        return brackets;
+    }
+    function getOpeningBracket(format) {
+        return brackets[format & 7680 /* BracketsMask */][0];
+    }
+    function getClosingBracket(format) {
+        return brackets[format & 7680 /* BracketsMask */][1];
+    }
+    // Flags enum to track count of temp variables and a few dedicated names
+    var TempFlags;
+    (function (TempFlags) {
+        TempFlags[TempFlags["Auto"] = 0] = "Auto";
+        TempFlags[TempFlags["CountMask"] = 268435455] = "CountMask";
+        TempFlags[TempFlags["_i"] = 268435456] = "_i";
+    })(TempFlags || (TempFlags = {}));
+})(ts || (ts = {}));
+/* @internal */
+var ts;
+(function (ts) {
+    function createCachedDirectoryStructureHost(host, currentDirectory, useCaseSensitiveFileNames) {
+        if (!host.getDirectories || !host.readDirectory) {
+            return undefined;
+        }
+        var cachedReadDirectoryResult = ts.createMap();
+        var getCanonicalFileName = ts.createGetCanonicalFileName(useCaseSensitiveFileNames);
+        return {
+            useCaseSensitiveFileNames: useCaseSensitiveFileNames,
+            fileExists: fileExists,
+            readFile: function (path, encoding) { return host.readFile(path, encoding); },
+            directoryExists: host.directoryExists && directoryExists,
+            getDirectories: getDirectories,
+            readDirectory: readDirectory,
+            createDirectory: host.createDirectory && createDirectory,
+            writeFile: host.writeFile && writeFile,
+            addOrDeleteFileOrDirectory: addOrDeleteFileOrDirectory,
+            addOrDeleteFile: addOrDeleteFile,
+            clearCache: clearCache
+        };
+        function toPath(fileName) {
+            return ts.toPath(fileName, currentDirectory, getCanonicalFileName);
+        }
+        function getCachedFileSystemEntries(rootDirPath) {
+            return cachedReadDirectoryResult.get(ts.ensureTrailingDirectorySeparator(rootDirPath));
+        }
+        function getCachedFileSystemEntriesForBaseDir(path) {
+            return getCachedFileSystemEntries(ts.getDirectoryPath(path));
+        }
+        function getBaseNameOfFileName(fileName) {
+            return ts.getBaseFileName(ts.normalizePath(fileName));
+        }
+        function createCachedFileSystemEntries(rootDir, rootDirPath) {
+            var resultFromHost = {
+                files: ts.map(host.readDirectory(rootDir, /*extensions*/ undefined, /*exclude*/ undefined, /*include*/ ["*.*"]), getBaseNameOfFileName) || [],
+                directories: host.getDirectories(rootDir) || []
+            };
+            cachedReadDirectoryResult.set(ts.ensureTrailingDirectorySeparator(rootDirPath), resultFromHost);
+            return resultFromHost;
+        }
+        /**
+         * If the readDirectory result was already cached, it returns that
+         * Otherwise gets result from host and caches it.
+         * The host request is done under try catch block to avoid caching incorrect result
+         */
+        function tryReadDirectory(rootDir, rootDirPath) {
+            rootDirPath = ts.ensureTrailingDirectorySeparator(rootDirPath);
+            var cachedResult = getCachedFileSystemEntries(rootDirPath);
+            if (cachedResult) {
+                return cachedResult;
+            }
+            try {
+                return createCachedFileSystemEntries(rootDir, rootDirPath);
+            }
+            catch (_e) {
+                // If there is exception to read directories, dont cache the result and direct the calls to host
+                ts.Debug.assert(!cachedReadDirectoryResult.has(ts.ensureTrailingDirectorySeparator(rootDirPath)));
+                return undefined;
+            }
+        }
+        function fileNameEqual(name1, name2) {
+            return getCanonicalFileName(name1) === getCanonicalFileName(name2);
+        }
+        function hasEntry(entries, name) {
+            return ts.some(entries, function (file) { return fileNameEqual(file, name); });
+        }
+        function updateFileSystemEntry(entries, baseName, isValid) {
+            if (hasEntry(entries, baseName)) {
+                if (!isValid) {
+                    return ts.filterMutate(entries, function (entry) { return !fileNameEqual(entry, baseName); });
+                }
+            }
+            else if (isValid) {
+                return entries.push(baseName);
+            }
+        }
+        function writeFile(fileName, data, writeByteOrderMark) {
+            var path = toPath(fileName);
+            var result = getCachedFileSystemEntriesForBaseDir(path);
+            if (result) {
+                updateFilesOfFileSystemEntry(result, getBaseNameOfFileName(fileName), /*fileExists*/ true);
+            }
+            return host.writeFile(fileName, data, writeByteOrderMark);
+        }
+        function fileExists(fileName) {
+            var path = toPath(fileName);
+            var result = getCachedFileSystemEntriesForBaseDir(path);
+            return result && hasEntry(result.files, getBaseNameOfFileName(fileName)) ||
+                host.fileExists(fileName);
+        }
+        function directoryExists(dirPath) {
+            var path = toPath(dirPath);
+            return cachedReadDirectoryResult.has(ts.ensureTrailingDirectorySeparator(path)) || host.directoryExists(dirPath);
+        }
+        function createDirectory(dirPath) {
+            var path = toPath(dirPath);
+            var result = getCachedFileSystemEntriesForBaseDir(path);
+            var baseFileName = getBaseNameOfFileName(dirPath);
+            if (result) {
+                updateFileSystemEntry(result.directories, baseFileName, /*isValid*/ true);
+            }
+            host.createDirectory(dirPath);
+        }
+        function getDirectories(rootDir) {
+            var rootDirPath = toPath(rootDir);
+            var result = tryReadDirectory(rootDir, rootDirPath);
+            if (result) {
+                return result.directories.slice();
+            }
+            return host.getDirectories(rootDir);
+        }
+        function readDirectory(rootDir, extensions, excludes, includes, depth) {
+            var rootDirPath = toPath(rootDir);
+            var result = tryReadDirectory(rootDir, rootDirPath);
+            if (result) {
+                return ts.matchFiles(rootDir, extensions, excludes, includes, useCaseSensitiveFileNames, currentDirectory, depth, getFileSystemEntries);
+            }
+            return host.readDirectory(rootDir, extensions, excludes, includes, depth);
+            function getFileSystemEntries(dir) {
+                var path = toPath(dir);
+                if (path === rootDirPath) {
+                    return result;
+                }
+                return tryReadDirectory(dir, path) || ts.emptyFileSystemEntries;
+            }
+        }
+        function addOrDeleteFileOrDirectory(fileOrDirectory, fileOrDirectoryPath) {
+            var existingResult = getCachedFileSystemEntries(fileOrDirectoryPath);
+            if (existingResult) {
+                // Just clear the cache for now
+                // For now just clear the cache, since this could mean that multiple level entries might need to be re-evaluated
+                clearCache();
+                return undefined;
+            }
+            var parentResult = getCachedFileSystemEntriesForBaseDir(fileOrDirectoryPath);
+            if (!parentResult) {
+                return undefined;
+            }
+            // This was earlier a file (hence not in cached directory contents)
+            // or we never cached the directory containing it
+            if (!host.directoryExists) {
+                // Since host doesnt support directory exists, clear the cache as otherwise it might not be same
+                clearCache();
+                return undefined;
+            }
+            var baseName = getBaseNameOfFileName(fileOrDirectory);
+            var fsQueryResult = {
+                fileExists: host.fileExists(fileOrDirectoryPath),
+                directoryExists: host.directoryExists(fileOrDirectoryPath)
+            };
+            if (fsQueryResult.directoryExists || hasEntry(parentResult.directories, baseName)) {
+                // Folder added or removed, clear the cache instead of updating the folder and its structure
+                clearCache();
+            }
+            else {
+                // No need to update the directory structure, just files
+                updateFilesOfFileSystemEntry(parentResult, baseName, fsQueryResult.fileExists);
+            }
+            return fsQueryResult;
+        }
+        function addOrDeleteFile(fileName, filePath, eventKind) {
+            if (eventKind === ts.FileWatcherEventKind.Changed) {
+                return;
+            }
+            var parentResult = getCachedFileSystemEntriesForBaseDir(filePath);
+            if (parentResult) {
+                updateFilesOfFileSystemEntry(parentResult, getBaseNameOfFileName(fileName), eventKind === ts.FileWatcherEventKind.Created);
+            }
+        }
+        function updateFilesOfFileSystemEntry(parentResult, baseName, fileExists) {
+            updateFileSystemEntry(parentResult.files, baseName, fileExists);
+        }
+        function clearCache() {
+            cachedReadDirectoryResult.clear();
+        }
+    }
+    ts.createCachedDirectoryStructureHost = createCachedDirectoryStructureHost;
+    var ConfigFileProgramReloadLevel;
+    (function (ConfigFileProgramReloadLevel) {
+        ConfigFileProgramReloadLevel[ConfigFileProgramReloadLevel["None"] = 0] = "None";
+        /** Update the file name list from the disk */
+        ConfigFileProgramReloadLevel[ConfigFileProgramReloadLevel["Partial"] = 1] = "Partial";
+        /** Reload completely by re-reading contents of config file from disk and updating program */
+        ConfigFileProgramReloadLevel[ConfigFileProgramReloadLevel["Full"] = 2] = "Full";
+    })(ConfigFileProgramReloadLevel = ts.ConfigFileProgramReloadLevel || (ts.ConfigFileProgramReloadLevel = {}));
+    /**
+     * Updates the existing missing file watches with the new set of missing files after new program is created
+     */
+    function updateMissingFilePathsWatch(program, missingFileWatches, createMissingFileWatch) {
+        var missingFilePaths = program.getMissingFilePaths();
+        var newMissingFilePathMap = ts.arrayToSet(missingFilePaths);
+        // Update the missing file paths watcher
+        ts.mutateMap(missingFileWatches, newMissingFilePathMap, {
+            // Watch the missing files
+            createNewValue: createMissingFileWatch,
+            // Files that are no longer missing (e.g. because they are no longer required)
+            // should no longer be watched.
+            onDeleteValue: ts.closeFileWatcher
+        });
+    }
+    ts.updateMissingFilePathsWatch = updateMissingFilePathsWatch;
+    /**
+     * Updates the existing wild card directory watches with the new set of wild card directories from the config file
+     * after new program is created because the config file was reloaded or program was created first time from the config file
+     * Note that there is no need to call this function when the program is updated with additional files without reloading config files,
+     * as wildcard directories wont change unless reloading config file
+     */
+    function updateWatchingWildcardDirectories(existingWatchedForWildcards, wildcardDirectories, watchDirectory) {
+        ts.mutateMap(existingWatchedForWildcards, wildcardDirectories, {
+            // Create new watch and recursive info
+            createNewValue: createWildcardDirectoryWatcher,
+            // Close existing watch thats not needed any more
+            onDeleteValue: closeFileWatcherOf,
+            // Close existing watch that doesnt match in the flags
+            onExistingValue: updateWildcardDirectoryWatcher
+        });
+        function createWildcardDirectoryWatcher(directory, flags) {
+            // Create new watch and recursive info
+            return {
+                watcher: watchDirectory(directory, flags),
+                flags: flags
+            };
+        }
+        function updateWildcardDirectoryWatcher(existingWatcher, flags, directory) {
+            // Watcher needs to be updated if the recursive flags dont match
+            if (existingWatcher.flags === flags) {
+                return;
+            }
+            existingWatcher.watcher.close();
+            existingWatchedForWildcards.set(directory, createWildcardDirectoryWatcher(directory, flags));
+        }
+    }
+    ts.updateWatchingWildcardDirectories = updateWatchingWildcardDirectories;
+    function isEmittedFileOfProgram(program, file) {
+        if (!program) {
+            return false;
+        }
+        return program.isEmittedFile(file);
+    }
+    ts.isEmittedFileOfProgram = isEmittedFileOfProgram;
+    var WatchLogLevel;
+    (function (WatchLogLevel) {
+        WatchLogLevel[WatchLogLevel["None"] = 0] = "None";
+        WatchLogLevel[WatchLogLevel["TriggerOnly"] = 1] = "TriggerOnly";
+        WatchLogLevel[WatchLogLevel["Verbose"] = 2] = "Verbose";
+    })(WatchLogLevel = ts.WatchLogLevel || (ts.WatchLogLevel = {}));
+    function getWatchFactory(watchLogLevel, log, getDetailWatchInfo) {
+        return getWatchFactoryWith(watchLogLevel, log, getDetailWatchInfo, watchFile, watchDirectory);
+    }
+    ts.getWatchFactory = getWatchFactory;
+    function getWatchFactoryWith(watchLogLevel, log, getDetailWatchInfo, watchFile, watchDirectory) {
+        var createFileWatcher = getCreateFileWatcher(watchLogLevel, watchFile);
+        var createFilePathWatcher = watchLogLevel === WatchLogLevel.None ? watchFilePath : createFileWatcher;
+        var createDirectoryWatcher = getCreateFileWatcher(watchLogLevel, watchDirectory);
+        return {
+            watchFile: function (host, file, callback, pollingInterval, detailInfo1, detailInfo2) {
+                return createFileWatcher(host, file, callback, pollingInterval, /*passThrough*/ undefined, detailInfo1, detailInfo2, watchFile, log, "FileWatcher", getDetailWatchInfo);
+            },
+            watchFilePath: function (host, file, callback, pollingInterval, path, detailInfo1, detailInfo2) {
+                return createFilePathWatcher(host, file, callback, pollingInterval, path, detailInfo1, detailInfo2, watchFile, log, "FileWatcher", getDetailWatchInfo);
+            },
+            watchDirectory: function (host, directory, callback, flags, detailInfo1, detailInfo2) {
+                return createDirectoryWatcher(host, directory, callback, flags, /*passThrough*/ undefined, detailInfo1, detailInfo2, watchDirectory, log, "DirectoryWatcher", getDetailWatchInfo);
+            }
+        };
+        function watchFilePath(host, file, callback, pollingInterval, path) {
+            return watchFile(host, file, function (fileName, eventKind) { return callback(fileName, eventKind, path); }, pollingInterval);
+        }
+    }
+    function watchFile(host, file, callback, pollingInterval) {
+        return host.watchFile(file, callback, pollingInterval);
+    }
+    function watchDirectory(host, directory, callback, flags) {
+        return host.watchDirectory(directory, callback, (flags & 1 /* Recursive */) !== 0);
+    }
+    function getCreateFileWatcher(watchLogLevel, addWatch) {
+        switch (watchLogLevel) {
+            case WatchLogLevel.None:
+                return addWatch;
+            case WatchLogLevel.TriggerOnly:
+                return createFileWatcherWithTriggerLogging;
+            case WatchLogLevel.Verbose:
+                return createFileWatcherWithLogging;
+        }
+    }
+    function createFileWatcherWithLogging(host, file, cb, flags, passThrough, detailInfo1, detailInfo2, addWatch, log, watchCaption, getDetailWatchInfo) {
+        log(watchCaption + ":: Added:: " + getWatchInfo(file, flags, detailInfo1, detailInfo2, getDetailWatchInfo));
+        var watcher = createFileWatcherWithTriggerLogging(host, file, cb, flags, passThrough, detailInfo1, detailInfo2, addWatch, log, watchCaption, getDetailWatchInfo);
+        return {
+            close: function () {
+                log(watchCaption + ":: Close:: " + getWatchInfo(file, flags, detailInfo1, detailInfo2, getDetailWatchInfo));
+                watcher.close();
+            }
+        };
+    }
+    function createFileWatcherWithTriggerLogging(host, file, cb, flags, passThrough, detailInfo1, detailInfo2, addWatch, log, watchCaption, getDetailWatchInfo) {
+        return addWatch(host, file, function (fileName, cbOptional) {
+            var triggerredInfo = watchCaption + ":: Triggered with " + fileName + (cbOptional !== undefined ? cbOptional : "") + ":: " + getWatchInfo(file, flags, detailInfo1, detailInfo2, getDetailWatchInfo);
+            log(triggerredInfo);
+            var start = ts.timestamp();
+            cb(fileName, cbOptional, passThrough);
+            var elapsed = ts.timestamp() - start;
+            log("Elapsed:: " + elapsed + "ms " + triggerredInfo);
+        }, flags);
+    }
+    function getWatchInfo(file, flags, detailInfo1, detailInfo2, getDetailWatchInfo) {
+        return "WatchInfo: " + file + " " + flags + " " + (getDetailWatchInfo ? getDetailWatchInfo(detailInfo1, detailInfo2) : detailInfo1);
+    }
+    function closeFileWatcherOf(objWithWatcher) {
+        objWithWatcher.watcher.close();
+    }
+    ts.closeFileWatcherOf = closeFileWatcherOf;
+})(ts || (ts = {}));
+var ts;
+(function (ts) {
+    var ignoreDiagnosticCommentRegEx = /(^\s*$)|(^\s*\/\/\/?\s*(@ts-ignore)?)/;
+    function findConfigFile(searchPath, fileExists, configName) {
+        if (configName === void 0) { configName = "tsconfig.json"; }
+        return ts.forEachAncestorDirectory(searchPath, function (ancestor) {
+            var fileName = ts.combinePaths(ancestor, configName);
+            return fileExists(fileName) ? fileName : undefined;
+        });
+    }
+    ts.findConfigFile = findConfigFile;
+    function resolveTripleslashReference(moduleName, containingFile) {
+        var basePath = ts.getDirectoryPath(containingFile);
+        var referencedFileName = ts.isRootedDiskPath(moduleName) ? moduleName : ts.combinePaths(basePath, moduleName);
+        return ts.normalizePath(referencedFileName);
+    }
+    ts.resolveTripleslashReference = resolveTripleslashReference;
+    /* @internal */
+    function computeCommonSourceDirectoryOfFilenames(fileNames, currentDirectory, getCanonicalFileName) {
+        var commonPathComponents;
+        var failed = ts.forEach(fileNames, function (sourceFile) {
+            // Each file contributes into common source file path
+            var sourcePathComponents = ts.getNormalizedPathComponents(sourceFile, currentDirectory);
+            sourcePathComponents.pop(); // The base file name is not part of the common directory path
+            if (!commonPathComponents) {
+                // first file
+                commonPathComponents = sourcePathComponents;
+                return;
+            }
+            var n = Math.min(commonPathComponents.length, sourcePathComponents.length);
+            for (var i = 0; i < n; i++) {
+                if (getCanonicalFileName(commonPathComponents[i]) !== getCanonicalFileName(sourcePathComponents[i])) {
+                    if (i === 0) {
+                        // Failed to find any common path component
+                        return true;
+                    }
+                    // New common path found that is 0 -> i-1
+                    commonPathComponents.length = i;
+                    break;
+                }
+            }
+            // If the sourcePathComponents was shorter than the commonPathComponents, truncate to the sourcePathComponents
+            if (sourcePathComponents.length < commonPathComponents.length) {
+                commonPathComponents.length = sourcePathComponents.length;
+            }
+        });
+        // A common path can not be found when paths span multiple drives on windows, for example
+        if (failed) {
+            return "";
+        }
+        if (!commonPathComponents) { // Can happen when all input files are .d.ts files
+            return currentDirectory;
+        }
+        return ts.getPathFromPathComponents(commonPathComponents);
+    }
+    ts.computeCommonSourceDirectoryOfFilenames = computeCommonSourceDirectoryOfFilenames;
+    function createCompilerHost(options, setParentNodes) {
+        var existingDirectories = ts.createMap();
+        function getCanonicalFileName(fileName) {
+            // if underlying system can distinguish between two files whose names differs only in cases then file name already in canonical form.
+            // otherwise use toLowerCase as a canonical form.
+            return ts.sys.useCaseSensitiveFileNames ? fileName : fileName.toLowerCase();
+        }
+        function getSourceFile(fileName, languageVersion, onError) {
+            var text;
+            try {
+                ts.performance.mark("beforeIORead");
+                text = ts.sys.readFile(fileName, options.charset);
+                ts.performance.mark("afterIORead");
+                ts.performance.measure("I/O Read", "beforeIORead", "afterIORead");
+            }
+            catch (e) {
+                if (onError) {
+                    onError(e.message);
+                }
+                text = "";
+            }
+            return text !== undefined ? ts.createSourceFile(fileName, text, languageVersion, setParentNodes) : undefined;
+        }
+        function directoryExists(directoryPath) {
+            if (existingDirectories.has(directoryPath)) {
+                return true;
+            }
+            if (ts.sys.directoryExists(directoryPath)) {
+                existingDirectories.set(directoryPath, true);
+                return true;
+            }
+            return false;
+        }
+        function ensureDirectoriesExist(directoryPath) {
+            if (directoryPath.length > ts.getRootLength(directoryPath) && !directoryExists(directoryPath)) {
+                var parentDirectory = ts.getDirectoryPath(directoryPath);
+                ensureDirectoriesExist(parentDirectory);
+                ts.sys.createDirectory(directoryPath);
+            }
+        }
+        var outputFingerprints;
+        function writeFileIfUpdated(fileName, data, writeByteOrderMark) {
+            if (!outputFingerprints) {
+                outputFingerprints = ts.createMap();
+            }
+            var hash = ts.sys.createHash(data); // TODO: GH#18217
+            var mtimeBefore = ts.sys.getModifiedTime(fileName); // TODO: GH#18217
+            if (mtimeBefore) {
+                var fingerprint = outputFingerprints.get(fileName);
+                // If output has not been changed, and the file has no external modification
+                if (fingerprint &&
+                    fingerprint.byteOrderMark === writeByteOrderMark &&
+                    fingerprint.hash === hash &&
+                    fingerprint.mtime.getTime() === mtimeBefore.getTime()) {
+                    return;
+                }
+            }
+            ts.sys.writeFile(fileName, data, writeByteOrderMark);
+            var mtimeAfter = ts.sys.getModifiedTime(fileName); // TODO: GH#18217
+            outputFingerprints.set(fileName, {
+                hash: hash,
+                byteOrderMark: writeByteOrderMark,
+                mtime: mtimeAfter
+            });
+        }
+        function writeFile(fileName, data, writeByteOrderMark, onError) {
+            try {
+                ts.performance.mark("beforeIOWrite");
+                ensureDirectoriesExist(ts.getDirectoryPath(ts.normalizePath(fileName)));
+                if (ts.isWatchSet(options) && ts.sys.createHash && ts.sys.getModifiedTime) {
+                    writeFileIfUpdated(fileName, data, writeByteOrderMark);
+                }
+                else {
+                    ts.sys.writeFile(fileName, data, writeByteOrderMark);
+                }
+                ts.performance.mark("afterIOWrite");
+                ts.performance.measure("I/O Write", "beforeIOWrite", "afterIOWrite");
+            }
+            catch (e) {
+                if (onError) {
+                    onError(e.message);
+                }
+            }
+        }
+        function getDefaultLibLocation() {
+            return ts.getDirectoryPath(ts.normalizePath(ts.sys.getExecutingFilePath()));
+        }
+        var newLine = ts.getNewLineCharacter(options);
+        var realpath = ts.sys.realpath && (function (path) { return ts.sys.realpath(path); });
+        return {
+            getSourceFile: getSourceFile,
+            getDefaultLibLocation: getDefaultLibLocation,
+            getDefaultLibFileName: function (options) { return ts.combinePaths(getDefaultLibLocation(), ts.getDefaultLibFileName(options)); },
+            writeFile: writeFile,
+            getCurrentDirectory: ts.memoize(function () { return ts.sys.getCurrentDirectory(); }),
+            useCaseSensitiveFileNames: function () { return ts.sys.useCaseSensitiveFileNames; },
+            getCanonicalFileName: getCanonicalFileName,
+            getNewLine: function () { return newLine; },
+            fileExists: function (fileName) { return ts.sys.fileExists(fileName); },
+            readFile: function (fileName) { return ts.sys.readFile(fileName); },
+            trace: function (s) { return ts.sys.write(s + newLine); },
+            directoryExists: function (directoryName) { return ts.sys.directoryExists(directoryName); },
+            getEnvironmentVariable: function (name) { return ts.sys.getEnvironmentVariable ? ts.sys.getEnvironmentVariable(name) : ""; },
+            getDirectories: function (path) { return ts.sys.getDirectories(path); },
+            realpath: realpath,
+            readDirectory: function (path, extensions, include, exclude, depth) { return ts.sys.readDirectory(path, extensions, include, exclude, depth); },
+            getModifiedTime: ts.sys.getModifiedTime && (function (path) { return ts.sys.getModifiedTime(path); }),
+            setModifiedTime: ts.sys.setModifiedTime && (function (path, date) { return ts.sys.setModifiedTime(path, date); }),
+            deleteFile: ts.sys.deleteFile && (function (path) { return ts.sys.deleteFile(path); })
+        };
+    }
+    ts.createCompilerHost = createCompilerHost;
+    function getPreEmitDiagnostics(program, sourceFile, cancellationToken) {
+        var diagnostics = program.getConfigFileParsingDiagnostics().concat(program.getOptionsDiagnostics(cancellationToken), program.getSyntacticDiagnostics(sourceFile, cancellationToken), program.getGlobalDiagnostics(cancellationToken), program.getSemanticDiagnostics(sourceFile, cancellationToken));
+        if (program.getCompilerOptions().declaration) {
+            ts.addRange(diagnostics, program.getDeclarationDiagnostics(sourceFile, cancellationToken));
+        }
+        return ts.sortAndDeduplicateDiagnostics(diagnostics);
+    }
+    ts.getPreEmitDiagnostics = getPreEmitDiagnostics;
+    function formatDiagnostics(diagnostics, host) {
+        var output = "";
+        for (var _i = 0, diagnostics_1 = diagnostics; _i < diagnostics_1.length; _i++) {
+            var diagnostic = diagnostics_1[_i];
+            output += formatDiagnostic(diagnostic, host);
+        }
+        return output;
+    }
+    ts.formatDiagnostics = formatDiagnostics;
+    function formatDiagnostic(diagnostic, host) {
+        var errorMessage = ts.diagnosticCategoryName(diagnostic) + " TS" + diagnostic.code + ": " + flattenDiagnosticMessageText(diagnostic.messageText, host.getNewLine()) + host.getNewLine();
+        if (diagnostic.file) {
+            var _a = ts.getLineAndCharacterOfPosition(diagnostic.file, diagnostic.start), line = _a.line, character = _a.character; // TODO: GH#18217
+            var fileName = diagnostic.file.fileName;
+            var relativeFileName = ts.convertToRelativePath(fileName, host.getCurrentDirectory(), function (fileName) { return host.getCanonicalFileName(fileName); });
+            return relativeFileName + "(" + (line + 1) + "," + (character + 1) + "): " + errorMessage;
+        }
+        return errorMessage;
+    }
+    ts.formatDiagnostic = formatDiagnostic;
+    /** @internal */
+    var ForegroundColorEscapeSequences;
+    (function (ForegroundColorEscapeSequences) {
+        ForegroundColorEscapeSequences["Grey"] = "\u001B[90m";
+        ForegroundColorEscapeSequences["Red"] = "\u001B[91m";
+        ForegroundColorEscapeSequences["Yellow"] = "\u001B[93m";
+        ForegroundColorEscapeSequences["Blue"] = "\u001B[94m";
+        ForegroundColorEscapeSequences["Cyan"] = "\u001B[96m";
+    })(ForegroundColorEscapeSequences = ts.ForegroundColorEscapeSequences || (ts.ForegroundColorEscapeSequences = {}));
+    var gutterStyleSequence = "\u001b[30;47m";
+    var gutterSeparator = " ";
+    var resetEscapeSequence = "\u001b[0m";
+    var ellipsis = "...";
+    function getCategoryFormat(category) {
+        switch (category) {
+            case ts.DiagnosticCategory.Error: return ForegroundColorEscapeSequences.Red;
+            case ts.DiagnosticCategory.Warning: return ForegroundColorEscapeSequences.Yellow;
+            case ts.DiagnosticCategory.Suggestion: return ts.Debug.fail("Should never get an Info diagnostic on the command line.");
+            case ts.DiagnosticCategory.Message: return ForegroundColorEscapeSequences.Blue;
+        }
+    }
+    /** @internal */
+    function formatColorAndReset(text, formatStyle) {
+        return formatStyle + text + resetEscapeSequence;
+    }
+    ts.formatColorAndReset = formatColorAndReset;
+    function padLeft(s, length) {
+        while (s.length < length) {
+            s = " " + s;
+        }
+        return s;
+    }
+    function formatDiagnosticsWithColorAndContext(diagnostics, host) {
+        var output = "";
+        for (var _i = 0, diagnostics_2 = diagnostics; _i < diagnostics_2.length; _i++) {
+            var diagnostic = diagnostics_2[_i];
+            var context = "";
+            if (diagnostic.file) {
+                var start = diagnostic.start, length_4 = diagnostic.length, file = diagnostic.file;
+                var _a = ts.getLineAndCharacterOfPosition(file, start), firstLine = _a.line, firstLineChar = _a.character; // TODO: GH#18217
+                var _b = ts.getLineAndCharacterOfPosition(file, start + length_4), lastLine = _b.line, lastLineChar = _b.character;
+                var lastLineInFile = ts.getLineAndCharacterOfPosition(file, file.text.length).line;
+                var relativeFileName = host ? ts.convertToRelativePath(file.fileName, host.getCurrentDirectory(), function (fileName) { return host.getCanonicalFileName(fileName); }) : file.fileName;
+                var hasMoreThanFiveLines = (lastLine - firstLine) >= 4;
+                var gutterWidth = (lastLine + 1 + "").length;
+                if (hasMoreThanFiveLines) {
+                    gutterWidth = Math.max(ellipsis.length, gutterWidth);
+                }
+                for (var i = firstLine; i <= lastLine; i++) {
+                    context += host.getNewLine();
+                    // If the error spans over 5 lines, we'll only show the first 2 and last 2 lines,
+                    // so we'll skip ahead to the second-to-last line.
+                    if (hasMoreThanFiveLines && firstLine + 1 < i && i < lastLine - 1) {
+                        context += formatColorAndReset(padLeft(ellipsis, gutterWidth), gutterStyleSequence) + gutterSeparator + host.getNewLine();
+                        i = lastLine - 1;
+                    }
+                    var lineStart = ts.getPositionOfLineAndCharacter(file, i, 0);
+                    var lineEnd = i < lastLineInFile ? ts.getPositionOfLineAndCharacter(file, i + 1, 0) : file.text.length;
+                    var lineContent = file.text.slice(lineStart, lineEnd);
+                    lineContent = lineContent.replace(/\s+$/g, ""); // trim from end
+                    lineContent = lineContent.replace("\t", " "); // convert tabs to single spaces
+                    // Output the gutter and the actual contents of the line.
+                    context += formatColorAndReset(padLeft(i + 1 + "", gutterWidth), gutterStyleSequence) + gutterSeparator;
+                    context += lineContent + host.getNewLine();
+                    // Output the gutter and the error span for the line using tildes.
+                    context += formatColorAndReset(padLeft("", gutterWidth), gutterStyleSequence) + gutterSeparator;
+                    context += ForegroundColorEscapeSequences.Red;
+                    if (i === firstLine) {
+                        // If we're on the last line, then limit it to the last character of the last line.
+                        // Otherwise, we'll just squiggle the rest of the line, giving 'slice' no end position.
+                        var lastCharForLine = i === lastLine ? lastLineChar : undefined;
+                        context += lineContent.slice(0, firstLineChar).replace(/\S/g, " ");
+                        context += lineContent.slice(firstLineChar, lastCharForLine).replace(/./g, "~");
+                    }
+                    else if (i === lastLine) {
+                        context += lineContent.slice(0, lastLineChar).replace(/./g, "~");
+                    }
+                    else {
+                        // Squiggle the entire line.
+                        context += lineContent.replace(/./g, "~");
+                    }
+                    context += resetEscapeSequence;
+                }
+                output += formatColorAndReset(relativeFileName, ForegroundColorEscapeSequences.Cyan);
+                output += ":";
+                output += formatColorAndReset("" + (firstLine + 1), ForegroundColorEscapeSequences.Yellow);
+                output += ":";
+                output += formatColorAndReset("" + (firstLineChar + 1), ForegroundColorEscapeSequences.Yellow);
+                output += " - ";
+            }
+            output += formatColorAndReset(ts.diagnosticCategoryName(diagnostic), getCategoryFormat(diagnostic.category));
+            output += formatColorAndReset(" TS" + diagnostic.code + ": ", ForegroundColorEscapeSequences.Grey);
+            output += flattenDiagnosticMessageText(diagnostic.messageText, host.getNewLine());
+            if (diagnostic.file) {
+                output += host.getNewLine();
+                output += context;
+            }
+            output += host.getNewLine();
+        }
+        return output;
+    }
+    ts.formatDiagnosticsWithColorAndContext = formatDiagnosticsWithColorAndContext;
+    function flattenDiagnosticMessageText(messageText, newLine) {
+        if (ts.isString(messageText)) {
+            return messageText;
+        }
+        else {
+            var diagnosticChain = messageText;
+            var result = "";
+            var indent = 0;
+            while (diagnosticChain) {
+                if (indent) {
+                    result += newLine;
+                    for (var i = 0; i < indent; i++) {
+                        result += "  ";
+                    }
+                }
+                result += diagnosticChain.messageText;
+                indent++;
+                diagnosticChain = diagnosticChain.next;
+            }
+            return result;
+        }
+    }
+    ts.flattenDiagnosticMessageText = flattenDiagnosticMessageText;
+    function loadWithLocalCache(names, containingFile, loader) {
+        if (names.length === 0) {
+            return [];
+        }
+        var resolutions = [];
+        var cache = ts.createMap();
+        for (var _i = 0, names_1 = names; _i < names_1.length; _i++) {
+            var name = names_1[_i];
+            var result = void 0;
+            if (cache.has(name)) {
+                result = cache.get(name);
+            }
+            else {
+                cache.set(name, result = loader(name, containingFile));
+            }
+            resolutions.push(result);
+        }
+        return resolutions;
+    }
+    /**
+     * Determines if program structure is upto date or needs to be recreated
+     */
+    /* @internal */
+    function isProgramUptoDate(program, rootFileNames, newOptions, getSourceVersion, fileExists, hasInvalidatedResolution, hasChangedAutomaticTypeDirectiveNames) {
+        // If we haven't created a program yet or have changed automatic type directives, then it is not up-to-date
+        if (!program || hasChangedAutomaticTypeDirectiveNames) {
+            return false;
+        }
+        // If number of files in the program do not match, it is not up-to-date
+        if (program.getRootFileNames().length !== rootFileNames.length) {
+            return false;
+        }
+        // If any file is not up-to-date, then the whole program is not up-to-date
+        if (program.getSourceFiles().some(sourceFileNotUptoDate)) {
+            return false;
+        }
+        // If any of the missing file paths are now created
+        if (program.getMissingFilePaths().some(fileExists)) {
+            return false;
+        }
+        var currentOptions = program.getCompilerOptions();
+        // If the compilation settings do no match, then the program is not up-to-date
+        if (!ts.compareDataObjects(currentOptions, newOptions)) {
+            return false;
+        }
+        // If everything matches but the text of config file is changed,
+        // error locations can change for program options, so update the program
+        if (currentOptions.configFile && newOptions.configFile) {
+            return currentOptions.configFile.text === newOptions.configFile.text;
+        }
+        return true;
+        function sourceFileNotUptoDate(sourceFile) {
+            return sourceFile.version !== getSourceVersion(sourceFile.path) ||
+                hasInvalidatedResolution(sourceFile.path);
+        }
+    }
+    ts.isProgramUptoDate = isProgramUptoDate;
+    function getConfigFileParsingDiagnostics(configFileParseResult) {
+        return configFileParseResult.options.configFile ? configFileParseResult.options.configFile.parseDiagnostics.concat(configFileParseResult.errors) :
+            configFileParseResult.errors;
+    }
+    ts.getConfigFileParsingDiagnostics = getConfigFileParsingDiagnostics;
+    /**
+     * Determined if source file needs to be re-created even if its text hasn't changed
+     */
+    function shouldProgramCreateNewSourceFiles(program, newOptions) {
+        // If any of these options change, we can't reuse old source file even if version match
+        // The change in options like these could result in change in syntax tree change
+        var oldOptions = program && program.getCompilerOptions();
+        return oldOptions && (oldOptions.target !== newOptions.target ||
+            oldOptions.module !== newOptions.module ||
+            oldOptions.moduleResolution !== newOptions.moduleResolution ||
+            oldOptions.noResolve !== newOptions.noResolve ||
+            oldOptions.jsx !== newOptions.jsx ||
+            oldOptions.allowJs !== newOptions.allowJs ||
+            oldOptions.disableSizeLimit !== newOptions.disableSizeLimit ||
+            oldOptions.baseUrl !== newOptions.baseUrl ||
+            !ts.equalOwnProperties(oldOptions.paths, newOptions.paths));
+    }
+    function createCreateProgramOptions(rootNames, options, host, oldProgram, configFileParsingDiagnostics) {
+        return {
+            rootNames: rootNames,
+            options: options,
+            host: host,
+            oldProgram: oldProgram,
+            configFileParsingDiagnostics: configFileParsingDiagnostics
+        };
+    }
+    function createProgram(rootNamesOrOptions, _options, _host, _oldProgram, _configFileParsingDiagnostics) {
+        var createProgramOptions = ts.isArray(rootNamesOrOptions) ? createCreateProgramOptions(rootNamesOrOptions, _options, _host, _oldProgram, _configFileParsingDiagnostics) : rootNamesOrOptions; // TODO: GH#18217
+        var rootNames = createProgramOptions.rootNames, options = createProgramOptions.options, configFileParsingDiagnostics = createProgramOptions.configFileParsingDiagnostics, projectReferences = createProgramOptions.projectReferences;
+        var oldProgram = createProgramOptions.oldProgram;
+        var program;
+        var processingDefaultLibFiles;
+        var processingOtherFiles;
+        var files;
+        var commonSourceDirectory;
+        var diagnosticsProducingTypeChecker;
+        var noDiagnosticsTypeChecker;
+        var classifiableNames;
+        var modifiedFilePaths;
+        var cachedSemanticDiagnosticsForFile = {};
+        var cachedDeclarationDiagnosticsForFile = {};
+        var resolvedTypeReferenceDirectives = ts.createMap();
+        var fileProcessingDiagnostics = ts.createDiagnosticCollection();
+        // The below settings are to track if a .js file should be add to the program if loaded via searching under node_modules.
+        // This works as imported modules are discovered recursively in a depth first manner, specifically:
+        // - For each root file, findSourceFile is called.
+        // - This calls processImportedModules for each module imported in the source file.
+        // - This calls resolveModuleNames, and then calls findSourceFile for each resolved module.
+        // As all these operations happen - and are nested - within the createProgram call, they close over the below variables.
+        // The current resolution depth is tracked by incrementing/decrementing as the depth first search progresses.
+        var maxNodeModuleJsDepth = typeof options.maxNodeModuleJsDepth === "number" ? options.maxNodeModuleJsDepth : 0;
+        var currentNodeModulesDepth = 0;
+        // If a module has some of its imports skipped due to being at the depth limit under node_modules, then track
+        // this, as it may be imported at a shallower depth later, and then it will need its skipped imports processed.
+        var modulesWithElidedImports = ts.createMap();
+        // Track source files that are source files found by searching under node_modules, as these shouldn't be compiled.
+        var sourceFilesFoundSearchingNodeModules = ts.createMap();
+        ts.performance.mark("beforeProgram");
+        var host = createProgramOptions.host || createCompilerHost(options);
+        var configParsingHost = parseConfigHostFromCompilerHost(host);
+        var skipDefaultLib = options.noLib;
+        var getDefaultLibraryFileName = ts.memoize(function () { return host.getDefaultLibFileName(options); });
+        var defaultLibraryPath = host.getDefaultLibLocation ? host.getDefaultLibLocation() : ts.getDirectoryPath(getDefaultLibraryFileName());
+        var programDiagnostics = ts.createDiagnosticCollection();
+        var currentDirectory = host.getCurrentDirectory();
+        var supportedExtensions = ts.getSupportedExtensions(options);
+        // Map storing if there is emit blocking diagnostics for given input
+        var hasEmitBlockingDiagnostics = ts.createMap();
+        var _compilerOptionsObjectLiteralSyntax;
+        var _referencesArrayLiteralSyntax;
+        var moduleResolutionCache;
+        var resolveModuleNamesWorker;
+        var hasInvalidatedResolution = host.hasInvalidatedResolution || ts.returnFalse;
+        if (host.resolveModuleNames) {
+            resolveModuleNamesWorker = function (moduleNames, containingFile, reusedNames) { return host.resolveModuleNames(ts.Debug.assertEachDefined(moduleNames), containingFile, reusedNames).map(function (resolved) {
+                // An older host may have omitted extension, in which case we should infer it from the file extension of resolvedFileName.
+                if (!resolved || resolved.extension !== undefined) {
+                    return resolved;
+                }
+                var withExtension = ts.clone(resolved);
+                withExtension.extension = ts.extensionFromPath(resolved.resolvedFileName);
+                return withExtension;
+            }); };
+        }
+        else {
+            moduleResolutionCache = ts.createModuleResolutionCache(currentDirectory, function (x) { return host.getCanonicalFileName(x); });
+            var loader_1 = function (moduleName, containingFile) { return ts.resolveModuleName(moduleName, containingFile, options, host, moduleResolutionCache).resolvedModule; }; // TODO: GH#18217
+            resolveModuleNamesWorker = function (moduleNames, containingFile) { return loadWithLocalCache(ts.Debug.assertEachDefined(moduleNames), containingFile, loader_1); };
+        }
+        var resolveTypeReferenceDirectiveNamesWorker;
+        if (host.resolveTypeReferenceDirectives) {
+            resolveTypeReferenceDirectiveNamesWorker = function (typeDirectiveNames, containingFile) { return host.resolveTypeReferenceDirectives(ts.Debug.assertEachDefined(typeDirectiveNames), containingFile); };
+        }
+        else {
+            var loader_2 = function (typesRef, containingFile) { return ts.resolveTypeReferenceDirective(typesRef, containingFile, options, host).resolvedTypeReferenceDirective; }; // TODO: GH#18217
+            resolveTypeReferenceDirectiveNamesWorker = function (typeReferenceDirectiveNames, containingFile) { return loadWithLocalCache(ts.Debug.assertEachDefined(typeReferenceDirectiveNames), containingFile, loader_2); };
+        }
+        // Map from a stringified PackageId to the source file with that id.
+        // Only one source file may have a given packageId. Others become redirects (see createRedirectSourceFile).
+        // `packageIdToSourceFile` is only used while building the program, while `sourceFileToPackageName` and `isSourceFileTargetOfRedirect` are kept around.
+        var packageIdToSourceFile = ts.createMap();
+        // Maps from a SourceFile's `.path` to the name of the package it was imported with.
+        var sourceFileToPackageName = ts.createMap();
+        var redirectTargetsSet = ts.createMap();
+        var filesByName = ts.createMap();
+        var missingFilePaths;
+        // stores 'filename -> file association' ignoring case
+        // used to track cases when two file names differ only in casing
+        var filesByNameIgnoreCase = host.useCaseSensitiveFileNames() ? ts.createMap() : undefined;
+        // A parallel array to projectReferences storing the results of reading in the referenced tsconfig files
+        var resolvedProjectReferences = projectReferences ? [] : undefined;
+        var projectReferenceRedirects = ts.createMap();
+        var shouldCreateNewSourceFile = shouldProgramCreateNewSourceFiles(oldProgram, options);
+        var structuralIsReused = tryReuseStructureFromOldProgram();
+        if (structuralIsReused !== 2 /* Completely */) {
+            processingDefaultLibFiles = [];
+            processingOtherFiles = [];
+            if (projectReferences) {
+                for (var _i = 0, projectReferences_1 = projectReferences; _i < projectReferences_1.length; _i++) {
+                    var ref = projectReferences_1[_i];
+                    var parsedRef = parseProjectReferenceConfigFile(ref);
+                    resolvedProjectReferences.push(parsedRef);
+                    if (parsedRef) {
+                        if (parsedRef.commandLine.options.outFile) {
+                            var dtsOutfile = ts.changeExtension(parsedRef.commandLine.options.outFile, ".d.ts");
+                            processSourceFile(dtsOutfile, /*isDefaultLib*/ false, /*ignoreNoDefaultLib*/ false, /*packageId*/ undefined);
+                        }
+                        addProjectReferenceRedirects(parsedRef.commandLine, projectReferenceRedirects);
+                    }
+                }
+            }
+            ts.forEach(rootNames, function (name) { return processRootFile(name, /*isDefaultLib*/ false, /*ignoreNoDefaultLib*/ false); });
+            // load type declarations specified via 'types' argument or implicitly from types/ and node_modules/@types folders
+            var typeReferences = ts.getAutomaticTypeDirectiveNames(options, host);
+            if (typeReferences.length) {
+                // This containingFilename needs to match with the one used in managed-side
+                var containingDirectory = options.configFilePath ? ts.getDirectoryPath(options.configFilePath) : host.getCurrentDirectory();
+                var containingFilename = ts.combinePaths(containingDirectory, "__inferred type names__.ts");
+                var resolutions = resolveTypeReferenceDirectiveNamesWorker(typeReferences, containingFilename);
+                for (var i = 0; i < typeReferences.length; i++) {
+                    processTypeReferenceDirective(typeReferences[i], resolutions[i]);
+                }
+            }
+            // Do not process the default library if:
+            //  - The '--noLib' flag is used.
+            //  - A 'no-default-lib' reference comment is encountered in
+            //      processing the root files.
+            if (!skipDefaultLib) {
+                // If '--lib' is not specified, include default library file according to '--target'
+                // otherwise, using options specified in '--lib' instead of '--target' default library file
+                var defaultLibraryFileName = getDefaultLibraryFileName();
+                if (!options.lib && defaultLibraryFileName) {
+                    processRootFile(defaultLibraryFileName, /*isDefaultLib*/ true, /*ignoreNoDefaultLib*/ false);
+                }
+                else {
+                    ts.forEach(options.lib, function (libFileName) {
+                        processRootFile(ts.combinePaths(defaultLibraryPath, libFileName), /*isDefaultLib*/ true, /*ignoreNoDefaultLib*/ false);
+                    });
+                }
+            }
+            missingFilePaths = ts.arrayFrom(filesByName.keys(), function (p) { return p; }).filter(function (p) { return !filesByName.get(p); });
+            files = ts.stableSort(processingDefaultLibFiles, compareDefaultLibFiles).concat(processingOtherFiles);
+            processingDefaultLibFiles = undefined;
+            processingOtherFiles = undefined;
+        }
+        ts.Debug.assert(!!missingFilePaths);
+        // Release any files we have acquired in the old program but are
+        // not part of the new program.
+        if (oldProgram && host.onReleaseOldSourceFile) {
+            var oldSourceFiles = oldProgram.getSourceFiles();
+            for (var _a = 0, oldSourceFiles_1 = oldSourceFiles; _a < oldSourceFiles_1.length; _a++) {
+                var oldSourceFile = oldSourceFiles_1[_a];
+                if (!getSourceFile(oldSourceFile.path) || shouldCreateNewSourceFile) {
+                    host.onReleaseOldSourceFile(oldSourceFile, oldProgram.getCompilerOptions());
+                }
+            }
+        }
+        // unconditionally set oldProgram to undefined to prevent it from being captured in closure
+        oldProgram = undefined;
+        program = {
+            getRootFileNames: function () { return rootNames; },
+            getSourceFile: getSourceFile,
+            getSourceFileByPath: getSourceFileByPath,
+            getSourceFiles: function () { return files; },
+            getMissingFilePaths: function () { return missingFilePaths; },
+            getCompilerOptions: function () { return options; },
+            getSyntacticDiagnostics: getSyntacticDiagnostics,
+            getOptionsDiagnostics: getOptionsDiagnostics,
+            getGlobalDiagnostics: getGlobalDiagnostics,
+            getSemanticDiagnostics: getSemanticDiagnostics,
+            getSuggestionDiagnostics: getSuggestionDiagnostics,
+            getDeclarationDiagnostics: getDeclarationDiagnostics,
+            getTypeChecker: getTypeChecker,
+            getClassifiableNames: getClassifiableNames,
+            getDiagnosticsProducingTypeChecker: getDiagnosticsProducingTypeChecker,
+            getCommonSourceDirectory: getCommonSourceDirectory,
+            emit: emit,
+            getCurrentDirectory: function () { return currentDirectory; },
+            getNodeCount: function () { return getDiagnosticsProducingTypeChecker().getNodeCount(); },
+            getIdentifierCount: function () { return getDiagnosticsProducingTypeChecker().getIdentifierCount(); },
+            getSymbolCount: function () { return getDiagnosticsProducingTypeChecker().getSymbolCount(); },
+            getTypeCount: function () { return getDiagnosticsProducingTypeChecker().getTypeCount(); },
+            getFileProcessingDiagnostics: function () { return fileProcessingDiagnostics; },
+            getResolvedTypeReferenceDirectives: function () { return resolvedTypeReferenceDirectives; },
+            isSourceFileFromExternalLibrary: isSourceFileFromExternalLibrary,
+            isSourceFileDefaultLibrary: isSourceFileDefaultLibrary,
+            dropDiagnosticsProducingTypeChecker: dropDiagnosticsProducingTypeChecker,
+            getSourceFileFromReference: getSourceFileFromReference,
+            getLibFileFromReference: getLibFileFromReference,
+            sourceFileToPackageName: sourceFileToPackageName,
+            redirectTargetsSet: redirectTargetsSet,
+            isEmittedFile: isEmittedFile,
+            getConfigFileParsingDiagnostics: getConfigFileParsingDiagnostics,
+            getResolvedModuleWithFailedLookupLocationsFromCache: getResolvedModuleWithFailedLookupLocationsFromCache,
+            getProjectReferences: getProjectReferences
+        };
+        verifyCompilerOptions();
+        ts.performance.mark("afterProgram");
+        ts.performance.measure("Program", "beforeProgram", "afterProgram");
+        return program;
+        function compareDefaultLibFiles(a, b) {
+            return ts.compareValues(getDefaultLibFilePriority(a), getDefaultLibFilePriority(b));
+        }
+        function getDefaultLibFilePriority(a) {
+            if (ts.containsPath(defaultLibraryPath, a.fileName, /*ignoreCase*/ false)) {
+                var basename = ts.getBaseFileName(a.fileName);
+                if (basename === "lib.d.ts" || basename === "lib.es6.d.ts")
+                    return 0;
+                var name = ts.removeSuffix(ts.removePrefix(basename, "lib."), ".d.ts");
+                var index = ts.libs.indexOf(name);
+                if (index !== -1)
+                    return index + 1;
+            }
+            return ts.libs.length + 2;
+        }
+        function getResolvedModuleWithFailedLookupLocationsFromCache(moduleName, containingFile) {
+            return moduleResolutionCache && ts.resolveModuleNameFromCache(moduleName, containingFile, moduleResolutionCache);
+        }
+        function toPath(fileName) {
+            return ts.toPath(fileName, currentDirectory, getCanonicalFileName);
+        }
+        function getCommonSourceDirectory() {
+            if (commonSourceDirectory === undefined) {
+                var emittedFiles = ts.filter(files, function (file) { return ts.sourceFileMayBeEmitted(file, options, isSourceFileFromExternalLibrary); });
+                if (options.rootDir && checkSourceFilesBelongToPath(emittedFiles, options.rootDir)) {
+                    // If a rootDir is specified use it as the commonSourceDirectory
+                    commonSourceDirectory = ts.getNormalizedAbsolutePath(options.rootDir, currentDirectory);
+                }
+                else if (options.composite) {
+                    // Project compilations never infer their root from the input source paths
+                    commonSourceDirectory = ts.getDirectoryPath(ts.normalizeSlashes(options.configFilePath)); // TODO: GH#18217
+                    checkSourceFilesBelongToPath(emittedFiles, commonSourceDirectory);
+                }
+                else {
+                    commonSourceDirectory = computeCommonSourceDirectory(emittedFiles);
+                }
+                if (commonSourceDirectory && commonSourceDirectory[commonSourceDirectory.length - 1] !== ts.directorySeparator) {
+                    // Make sure directory path ends with directory separator so this string can directly
+                    // used to replace with "" to get the relative path of the source file and the relative path doesn't
+                    // start with / making it rooted path
+                    commonSourceDirectory += ts.directorySeparator;
+                }
+            }
+            return commonSourceDirectory;
+        }
+        function getClassifiableNames() {
+            if (!classifiableNames) {
+                // Initialize a checker so that all our files are bound.
+                getTypeChecker();
+                classifiableNames = ts.createUnderscoreEscapedMap();
+                for (var _i = 0, files_2 = files; _i < files_2.length; _i++) {
+                    var sourceFile = files_2[_i];
+                    ts.copyEntries(sourceFile.classifiableNames, classifiableNames);
+                }
+            }
+            return classifiableNames;
+        }
+        function resolveModuleNamesReusingOldState(moduleNames, containingFile, file, oldProgramState) {
+            if (structuralIsReused === 0 /* Not */ && !file.ambientModuleNames.length) {
+                // If the old program state does not permit reusing resolutions and `file` does not contain locally defined ambient modules,
+                // the best we can do is fallback to the default logic.
+                return resolveModuleNamesWorker(moduleNames, containingFile);
+            }
+            var oldSourceFile = oldProgramState.program && oldProgramState.program.getSourceFile(containingFile);
+            if (oldSourceFile !== file && file.resolvedModules) {
+                // `file` was created for the new program.
+                //
+                // We only set `file.resolvedModules` via work from the current function,
+                // so it is defined iff we already called the current function on `file`.
+                // That call happened no later than the creation of the `file` object,
+                // which per above occurred during the current program creation.
+                // Since we assume the filesystem does not change during program creation,
+                // it is safe to reuse resolutions from the earlier call.
+                var result_4 = [];
+                for (var _i = 0, moduleNames_1 = moduleNames; _i < moduleNames_1.length; _i++) {
+                    var moduleName = moduleNames_1[_i];
+                    var resolvedModule = file.resolvedModules.get(moduleName);
+                    result_4.push(resolvedModule);
+                }
+                return result_4;
+            }
+            // At this point, we know at least one of the following hold:
+            // - file has local declarations for ambient modules
+            // - old program state is available
+            // With this information, we can infer some module resolutions without performing resolution.
+            /** An ordered list of module names for which we cannot recover the resolution. */
+            var unknownModuleNames;
+            /**
+             * The indexing of elements in this list matches that of `moduleNames`.
+             *
+             * Before combining results, result[i] is in one of the following states:
+             * * undefined: needs to be recomputed,
+             * * predictedToResolveToAmbientModuleMarker: known to be an ambient module.
+             * Needs to be reset to undefined before returning,
+             * * ResolvedModuleFull instance: can be reused.
+             */
+            var result;
+            var reusedNames;
+            /** A transient placeholder used to mark predicted resolution in the result list. */
+            var predictedToResolveToAmbientModuleMarker = {};
+            for (var i = 0; i < moduleNames.length; i++) {
+                var moduleName = moduleNames[i];
+                // If the source file is unchanged and doesnt have invalidated resolution, reuse the module resolutions
+                if (file === oldSourceFile && !hasInvalidatedResolution(oldSourceFile.path)) {
+                    var oldResolvedModule = oldSourceFile && oldSourceFile.resolvedModules.get(moduleName);
+                    if (oldResolvedModule) {
+                        if (ts.isTraceEnabled(options, host)) {
+                            ts.trace(host, ts.Diagnostics.Reusing_resolution_of_module_0_to_file_1_from_old_program, moduleName, containingFile);
+                        }
+                        (result || (result = new Array(moduleNames.length)))[i] = oldResolvedModule;
+                        (reusedNames || (reusedNames = [])).push(moduleName);
+                        continue;
+                    }
+                }
+                // We know moduleName resolves to an ambient module provided that moduleName:
+                // - is in the list of ambient modules locally declared in the current source file.
+                // - resolved to an ambient module in the old program whose declaration is in an unmodified file
+                //   (so the same module declaration will land in the new program)
+                var resolvesToAmbientModuleInNonModifiedFile = false;
+                if (ts.contains(file.ambientModuleNames, moduleName)) {
+                    resolvesToAmbientModuleInNonModifiedFile = true;
+                    if (ts.isTraceEnabled(options, host)) {
+                        ts.trace(host, ts.Diagnostics.Module_0_was_resolved_as_locally_declared_ambient_module_in_file_1, moduleName, containingFile);
+                    }
+                }
+                else {
+                    resolvesToAmbientModuleInNonModifiedFile = moduleNameResolvesToAmbientModuleInNonModifiedFile(moduleName, oldProgramState);
+                }
+                if (resolvesToAmbientModuleInNonModifiedFile) {
+                    (result || (result = new Array(moduleNames.length)))[i] = predictedToResolveToAmbientModuleMarker;
+                }
+                else {
+                    // Resolution failed in the old program, or resolved to an ambient module for which we can't reuse the result.
+                    (unknownModuleNames || (unknownModuleNames = [])).push(moduleName);
+                }
+            }
+            var resolutions = unknownModuleNames && unknownModuleNames.length
+                ? resolveModuleNamesWorker(unknownModuleNames, containingFile, reusedNames)
+                : ts.emptyArray;
+            // Combine results of resolutions and predicted results
+            if (!result) {
+                // There were no unresolved/ambient resolutions.
+                ts.Debug.assert(resolutions.length === moduleNames.length);
+                return resolutions;
+            }
+            var j = 0;
+            for (var i = 0; i < result.length; i++) {
+                if (result[i]) {
+                    // `result[i]` is either a `ResolvedModuleFull` or a marker.
+                    // If it is the former, we can leave it as is.
+                    if (result[i] === predictedToResolveToAmbientModuleMarker) {
+                        result[i] = undefined; // TODO: GH#18217
+                    }
+                }
+                else {
+                    result[i] = resolutions[j];
+                    j++;
+                }
+            }
+            ts.Debug.assert(j === resolutions.length);
+            return result;
+            // If we change our policy of rechecking failed lookups on each program create,
+            // we should adjust the value returned here.
+            function moduleNameResolvesToAmbientModuleInNonModifiedFile(moduleName, oldProgramState) {
+                var resolutionToFile = ts.getResolvedModule(oldProgramState.oldSourceFile, moduleName); // TODO: GH#18217
+                var resolvedFile = resolutionToFile && oldProgramState.program && oldProgramState.program.getSourceFile(resolutionToFile.resolvedFileName);
+                if (resolutionToFile && resolvedFile && !resolvedFile.externalModuleIndicator) {
+                    // In the old program, we resolved to an ambient module that was in the same
+                    //   place as we expected to find an actual module file.
+                    // We actually need to return 'false' here even though this seems like a 'true' case
+                    //   because the normal module resolution algorithm will find this anyway.
+                    return false;
+                }
+                var ambientModule = oldProgramState.program && oldProgramState.program.getTypeChecker().tryFindAmbientModuleWithoutAugmentations(moduleName);
+                if (!(ambientModule && ambientModule.declarations)) {
+                    return false;
+                }
+                // at least one of declarations should come from non-modified source file
+                var firstUnmodifiedFile = ts.forEach(ambientModule.declarations, function (d) {
+                    var f = ts.getSourceFileOfNode(d);
+                    return !ts.contains(oldProgramState.modifiedFilePaths, f.path) && f;
+                });
+                if (!firstUnmodifiedFile) {
+                    return false;
+                }
+                if (ts.isTraceEnabled(options, host)) {
+                    ts.trace(host, ts.Diagnostics.Module_0_was_resolved_as_ambient_module_declared_in_1_since_this_file_was_not_modified, moduleName, firstUnmodifiedFile.fileName);
+                }
+                return true;
+            }
+        }
+        function tryReuseStructureFromOldProgram() {
+            if (!oldProgram) {
+                return 0 /* Not */;
+            }
+            // check properties that can affect structure of the program or module resolution strategy
+            // if any of these properties has changed - structure cannot be reused
+            var oldOptions = oldProgram.getCompilerOptions();
+            if (ts.changesAffectModuleResolution(oldOptions, options)) {
+                return oldProgram.structureIsReused = 0 /* Not */;
+            }
+            ts.Debug.assert(!(oldProgram.structureIsReused & (2 /* Completely */ | 1 /* SafeModules */)));
+            // there is an old program, check if we can reuse its structure
+            var oldRootNames = oldProgram.getRootFileNames();
+            if (!ts.arrayIsEqualTo(oldRootNames, rootNames)) {
+                return oldProgram.structureIsReused = 0 /* Not */;
+            }
+            if (!ts.arrayIsEqualTo(options.types, oldOptions.types)) {
+                return oldProgram.structureIsReused = 0 /* Not */;
+            }
+            // Check if any referenced project tsconfig files are different
+            var oldRefs = oldProgram.getProjectReferences();
+            if (projectReferences) {
+                if (!oldRefs) {
+                    return oldProgram.structureIsReused = 0 /* Not */;
+                }
+                for (var i = 0; i < projectReferences.length; i++) {
+                    var oldRef = oldRefs[i];
+                    if (oldRef) {
+                        var newRef = parseProjectReferenceConfigFile(projectReferences[i]);
+                        if (!newRef || newRef.sourceFile !== oldRef.sourceFile) {
+                            // Resolved project reference has gone missing or changed
+                            return oldProgram.structureIsReused = 0 /* Not */;
+                        }
+                    }
+                    else {
+                        // A previously-unresolved reference may be resolved now
+                        if (parseProjectReferenceConfigFile(projectReferences[i]) !== undefined) {
+                            return oldProgram.structureIsReused = 0 /* Not */;
+                        }
+                    }
+                }
+            }
+            else {
+                if (oldRefs) {
+                    return oldProgram.structureIsReused = 0 /* Not */;
+                }
+            }
+            // check if program source files has changed in the way that can affect structure of the program
+            var newSourceFiles = [];
+            var filePaths = [];
+            var modifiedSourceFiles = [];
+            oldProgram.structureIsReused = 2 /* Completely */;
+            // If the missing file paths are now present, it can change the progam structure,
+            // and hence cant reuse the structure.
+            // This is same as how we dont reuse the structure if one of the file from old program is now missing
+            if (oldProgram.getMissingFilePaths().some(function (missingFilePath) { return host.fileExists(missingFilePath); })) {
+                return oldProgram.structureIsReused = 0 /* Not */;
+            }
+            var oldSourceFiles = oldProgram.getSourceFiles();
+            var SeenPackageName;
+            (function (SeenPackageName) {
+                SeenPackageName[SeenPackageName["Exists"] = 0] = "Exists";
+                SeenPackageName[SeenPackageName["Modified"] = 1] = "Modified";
+            })(SeenPackageName || (SeenPackageName = {}));
+            var seenPackageNames = ts.createMap();
+            for (var _i = 0, oldSourceFiles_2 = oldSourceFiles; _i < oldSourceFiles_2.length; _i++) {
+                var oldSourceFile = oldSourceFiles_2[_i];
+                var newSourceFile = host.getSourceFileByPath
+                    ? host.getSourceFileByPath(oldSourceFile.fileName, oldSourceFile.resolvedPath || oldSourceFile.path, options.target, /*onError*/ undefined, shouldCreateNewSourceFile)
+                    : host.getSourceFile(oldSourceFile.fileName, options.target, /*onError*/ undefined, shouldCreateNewSourceFile); // TODO: GH#18217
+                if (!newSourceFile) {
+                    return oldProgram.structureIsReused = 0 /* Not */;
+                }
+                ts.Debug.assert(!newSourceFile.redirectInfo, "Host should not return a redirect source file from `getSourceFile`");
+                var fileChanged = void 0;
+                if (oldSourceFile.redirectInfo) {
+                    // We got `newSourceFile` by path, so it is actually for the unredirected file.
+                    // This lets us know if the unredirected file has changed. If it has we should break the redirect.
+                    if (newSourceFile !== oldSourceFile.redirectInfo.unredirected) {
+                        // Underlying file has changed. Might not redirect anymore. Must rebuild program.
+                        return oldProgram.structureIsReused = 0 /* Not */;
+                    }
+                    fileChanged = false;
+                    newSourceFile = oldSourceFile; // Use the redirect.
+                }
+                else if (oldProgram.redirectTargetsSet.has(oldSourceFile.path)) {
+                    // If a redirected-to source file changes, the redirect may be broken.
+                    if (newSourceFile !== oldSourceFile) {
+                        return oldProgram.structureIsReused = 0 /* Not */;
+                    }
+                    fileChanged = false;
+                }
+                else {
+                    fileChanged = newSourceFile !== oldSourceFile;
+                }
+                newSourceFile.path = oldSourceFile.path;
+                filePaths.push(newSourceFile.path);
+                var packageName = oldProgram.sourceFileToPackageName.get(oldSourceFile.path);
+                if (packageName !== undefined) {
+                    // If there are 2 different source files for the same package name and at least one of them changes,
+                    // they might become redirects. So we must rebuild the program.
+                    var prevKind = seenPackageNames.get(packageName);
+                    var newKind = fileChanged ? 1 /* Modified */ : 0 /* Exists */;
+                    if ((prevKind !== undefined && newKind === 1 /* Modified */) || prevKind === 1 /* Modified */) {
+                        return oldProgram.structureIsReused = 0 /* Not */;
+                    }
+                    seenPackageNames.set(packageName, newKind);
+                }
+                if (fileChanged) {
+                    // The `newSourceFile` object was created for the new program.
+                    if (!ts.arrayIsEqualTo(oldSourceFile.libReferenceDirectives, newSourceFile.libReferenceDirectives, fileReferenceIsEqualTo)) {
+                        // 'lib' references has changed. Matches behavior in changesAffectModuleResolution
+                        return oldProgram.structureIsReused = 0 /* Not */;
+                    }
+                    if (oldSourceFile.hasNoDefaultLib !== newSourceFile.hasNoDefaultLib) {
+                        // value of no-default-lib has changed
+                        // this will affect if default library is injected into the list of files
+                        oldProgram.structureIsReused = 1 /* SafeModules */;
+                    }
+                    // check tripleslash references
+                    if (!ts.arrayIsEqualTo(oldSourceFile.referencedFiles, newSourceFile.referencedFiles, fileReferenceIsEqualTo)) {
+                        // tripleslash references has changed
+                        oldProgram.structureIsReused = 1 /* SafeModules */;
+                    }
+                    // check imports and module augmentations
+                    collectExternalModuleReferences(newSourceFile);
+                    if (!ts.arrayIsEqualTo(oldSourceFile.imports, newSourceFile.imports, moduleNameIsEqualTo)) {
+                        // imports has changed
+                        oldProgram.structureIsReused = 1 /* SafeModules */;
+                    }
+                    if (!ts.arrayIsEqualTo(oldSourceFile.moduleAugmentations, newSourceFile.moduleAugmentations, moduleNameIsEqualTo)) {
+                        // moduleAugmentations has changed
+                        oldProgram.structureIsReused = 1 /* SafeModules */;
+                    }
+                    if ((oldSourceFile.flags & 1572864 /* PermanentlySetIncrementalFlags */) !== (newSourceFile.flags & 1572864 /* PermanentlySetIncrementalFlags */)) {
+                        // dynamicImport has changed
+                        oldProgram.structureIsReused = 1 /* SafeModules */;
+                    }
+                    if (!ts.arrayIsEqualTo(oldSourceFile.typeReferenceDirectives, newSourceFile.typeReferenceDirectives, fileReferenceIsEqualTo)) {
+                        // 'types' references has changed
+                        oldProgram.structureIsReused = 1 /* SafeModules */;
+                    }
+                    // tentatively approve the file
+                    modifiedSourceFiles.push({ oldFile: oldSourceFile, newFile: newSourceFile });
+                }
+                else if (hasInvalidatedResolution(oldSourceFile.path)) {
+                    // 'module/types' references could have changed
+                    oldProgram.structureIsReused = 1 /* SafeModules */;
+                    // add file to the modified list so that we will resolve it later
+                    modifiedSourceFiles.push({ oldFile: oldSourceFile, newFile: newSourceFile });
+                }
+                // if file has passed all checks it should be safe to reuse it
+                newSourceFiles.push(newSourceFile);
+            }
+            if (oldProgram.structureIsReused !== 2 /* Completely */) {
+                return oldProgram.structureIsReused;
+            }
+            modifiedFilePaths = modifiedSourceFiles.map(function (f) { return f.newFile.path; });
+            // try to verify results of module resolution
+            for (var _a = 0, modifiedSourceFiles_1 = modifiedSourceFiles; _a < modifiedSourceFiles_1.length; _a++) {
+                var _b = modifiedSourceFiles_1[_a], oldSourceFile = _b.oldFile, newSourceFile = _b.newFile;
+                var newSourceFilePath = ts.getNormalizedAbsolutePath(newSourceFile.fileName, currentDirectory);
+                if (resolveModuleNamesWorker) {
+                    var moduleNames = getModuleNames(newSourceFile);
+                    var oldProgramState = { program: oldProgram, oldSourceFile: oldSourceFile, modifiedFilePaths: modifiedFilePaths };
+                    var resolutions = resolveModuleNamesReusingOldState(moduleNames, newSourceFilePath, newSourceFile, oldProgramState);
+                    // ensure that module resolution results are still correct
+                    var resolutionsChanged = ts.hasChangesInResolutions(moduleNames, resolutions, oldSourceFile.resolvedModules, ts.moduleResolutionIsEqualTo);
+                    if (resolutionsChanged) {
+                        oldProgram.structureIsReused = 1 /* SafeModules */;
+                        newSourceFile.resolvedModules = ts.zipToMap(moduleNames, resolutions);
+                    }
+                    else {
+                        newSourceFile.resolvedModules = oldSourceFile.resolvedModules;
+                    }
+                }
+                if (resolveTypeReferenceDirectiveNamesWorker) {
+                    var typesReferenceDirectives = ts.map(newSourceFile.typeReferenceDirectives, function (x) { return x.fileName; });
+                    var resolutions = resolveTypeReferenceDirectiveNamesWorker(typesReferenceDirectives, newSourceFilePath);
+                    // ensure that types resolutions are still correct
+                    var resolutionsChanged = ts.hasChangesInResolutions(typesReferenceDirectives, resolutions, oldSourceFile.resolvedTypeReferenceDirectiveNames, ts.typeDirectiveIsEqualTo);
+                    if (resolutionsChanged) {
+                        oldProgram.structureIsReused = 1 /* SafeModules */;
+                        newSourceFile.resolvedTypeReferenceDirectiveNames = ts.zipToMap(typesReferenceDirectives, resolutions);
+                    }
+                    else {
+                        newSourceFile.resolvedTypeReferenceDirectiveNames = oldSourceFile.resolvedTypeReferenceDirectiveNames;
+                    }
+                }
+            }
+            if (oldProgram.structureIsReused !== 2 /* Completely */) {
+                return oldProgram.structureIsReused;
+            }
+            if (host.hasChangedAutomaticTypeDirectiveNames) {
+                return oldProgram.structureIsReused = 1 /* SafeModules */;
+            }
+            missingFilePaths = oldProgram.getMissingFilePaths();
+            // update fileName -> file mapping
+            for (var i = 0; i < newSourceFiles.length; i++) {
+                filesByName.set(filePaths[i], newSourceFiles[i]);
+                // Set the file as found during node modules search if it was found that way in old progra,
+                if (oldProgram.isSourceFileFromExternalLibrary(oldProgram.getSourceFileByPath(filePaths[i]))) {
+                    sourceFilesFoundSearchingNodeModules.set(filePaths[i], true);
+                }
+            }
+            files = newSourceFiles;
+            fileProcessingDiagnostics = oldProgram.getFileProcessingDiagnostics();
+            for (var _c = 0, modifiedSourceFiles_2 = modifiedSourceFiles; _c < modifiedSourceFiles_2.length; _c++) {
+                var modifiedFile = modifiedSourceFiles_2[_c];
+                fileProcessingDiagnostics.reattachFileDiagnostics(modifiedFile.newFile);
+            }
+            resolvedTypeReferenceDirectives = oldProgram.getResolvedTypeReferenceDirectives();
+            sourceFileToPackageName = oldProgram.sourceFileToPackageName;
+            redirectTargetsSet = oldProgram.redirectTargetsSet;
+            return oldProgram.structureIsReused = 2 /* Completely */;
+        }
+        function getEmitHost(writeFileCallback) {
+            return __assign({ getPrependNodes: getPrependNodes,
+                getCanonicalFileName: getCanonicalFileName, getCommonSourceDirectory: program.getCommonSourceDirectory, getCompilerOptions: program.getCompilerOptions, getCurrentDirectory: function () { return currentDirectory; }, getNewLine: function () { return host.getNewLine(); }, getSourceFile: program.getSourceFile, getSourceFileByPath: program.getSourceFileByPath, getSourceFiles: program.getSourceFiles, isSourceFileFromExternalLibrary: isSourceFileFromExternalLibrary, writeFile: writeFileCallback || (function (fileName, data, writeByteOrderMark, onError, sourceFiles) { return host.writeFile(fileName, data, writeByteOrderMark, onError, sourceFiles); }), isEmitBlocked: isEmitBlocked, readFile: function (f) { return host.readFile(f); }, fileExists: function (f) { return host.fileExists(f); } }, (host.directoryExists ? { directoryExists: function (f) { return host.directoryExists(f); } } : {}));
+        }
+        function getProjectReferences() {
+            if (!resolvedProjectReferences)
+                return;
+            return resolvedProjectReferences;
+        }
+        function getPrependNodes() {
+            if (!projectReferences) {
+                return ts.emptyArray;
+            }
+            var nodes = [];
+            for (var i = 0; i < projectReferences.length; i++) {
+                var ref = projectReferences[i];
+                var resolvedRefOpts = resolvedProjectReferences[i].commandLine;
+                if (ref.prepend && resolvedRefOpts && resolvedRefOpts.options) {
+                    // Upstream project didn't have outFile set -- skip (error will have been issued earlier)
+                    if (!resolvedRefOpts.options.outFile)
+                        continue;
+                    var dtsFilename = ts.changeExtension(resolvedRefOpts.options.outFile, ".d.ts");
+                    var js = host.readFile(resolvedRefOpts.options.outFile) || "/* Input file " + resolvedRefOpts.options.outFile + " was missing */\r\n";
+                    var jsMap = host.readFile(resolvedRefOpts.options.outFile + ".map"); // TODO: try to read sourceMappingUrl comment from the js file
+                    var dts = host.readFile(dtsFilename) || "/* Input file " + dtsFilename + " was missing */\r\n";
+                    var dtsMap = host.readFile(dtsFilename + ".map");
+                    var node = ts.createInputFiles(js, dts, jsMap, dtsMap);
+                    nodes.push(node);
+                }
+            }
+            return nodes;
+        }
+        function isSourceFileFromExternalLibrary(file) {
+            return !!sourceFilesFoundSearchingNodeModules.get(file.path);
+        }
+        function isSourceFileDefaultLibrary(file) {
+            if (file.hasNoDefaultLib) {
+                return true;
+            }
+            if (!options.noLib) {
+                return false;
+            }
+            // If '--lib' is not specified, include default library file according to '--target'
+            // otherwise, using options specified in '--lib' instead of '--target' default library file
+            var equalityComparer = host.useCaseSensitiveFileNames() ? ts.equateStringsCaseSensitive : ts.equateStringsCaseInsensitive;
+            if (!options.lib) {
+                return equalityComparer(file.fileName, getDefaultLibraryFileName());
+            }
+            else {
+                return ts.some(options.lib, function (libFileName) { return equalityComparer(file.fileName, ts.combinePaths(defaultLibraryPath, libFileName)); });
+            }
+        }
+        function getDiagnosticsProducingTypeChecker() {
+            return diagnosticsProducingTypeChecker || (diagnosticsProducingTypeChecker = ts.createTypeChecker(program, /*produceDiagnostics:*/ true));
+        }
+        function dropDiagnosticsProducingTypeChecker() {
+            diagnosticsProducingTypeChecker = undefined;
+        }
+        function getTypeChecker() {
+            return noDiagnosticsTypeChecker || (noDiagnosticsTypeChecker = ts.createTypeChecker(program, /*produceDiagnostics:*/ false));
+        }
+        function emit(sourceFile, writeFileCallback, cancellationToken, emitOnlyDtsFiles, transformers) {
+            return runWithCancellationToken(function () { return emitWorker(program, sourceFile, writeFileCallback, cancellationToken, emitOnlyDtsFiles, transformers); });
+        }
+        function isEmitBlocked(emitFileName) {
+            return hasEmitBlockingDiagnostics.has(toPath(emitFileName));
+        }
+        function emitWorker(program, sourceFile, writeFileCallback, cancellationToken, emitOnlyDtsFiles, customTransformers) {
+            var declarationDiagnostics = [];
+            if (!emitOnlyDtsFiles) {
+                if (options.noEmit) {
+                    return { diagnostics: declarationDiagnostics, sourceMaps: undefined, emittedFiles: undefined, emitSkipped: true };
+                }
+                // If the noEmitOnError flag is set, then check if we have any errors so far.  If so,
+                // immediately bail out.  Note that we pass 'undefined' for 'sourceFile' so that we
+                // get any preEmit diagnostics, not just the ones
+                if (options.noEmitOnError) {
+                    var diagnostics = program.getOptionsDiagnostics(cancellationToken).concat(program.getSyntacticDiagnostics(sourceFile, cancellationToken), program.getGlobalDiagnostics(cancellationToken), program.getSemanticDiagnostics(sourceFile, cancellationToken));
+                    if (diagnostics.length === 0 && program.getCompilerOptions().declaration) {
+                        declarationDiagnostics = program.getDeclarationDiagnostics(/*sourceFile*/ undefined, cancellationToken);
+                    }
+                    if (diagnostics.length > 0 || declarationDiagnostics.length > 0) {
+                        return {
+                            diagnostics: ts.concatenate(diagnostics, declarationDiagnostics),
+                            sourceMaps: undefined,
+                            emittedFiles: undefined,
+                            emitSkipped: true
+                        };
+                    }
+                }
+            }
+            // Create the emit resolver outside of the "emitTime" tracking code below.  That way
+            // any cost associated with it (like type checking) are appropriate associated with
+            // the type-checking counter.
+            //
+            // If the -out option is specified, we should not pass the source file to getEmitResolver.
+            // This is because in the -out scenario all files need to be emitted, and therefore all
+            // files need to be type checked. And the way to specify that all files need to be type
+            // checked is to not pass the file to getEmitResolver.
+            var emitResolver = getDiagnosticsProducingTypeChecker().getEmitResolver((options.outFile || options.out) ? undefined : sourceFile, cancellationToken);
+            ts.performance.mark("beforeEmit");
+            var transformers = emitOnlyDtsFiles ? [] : ts.getTransformers(options, customTransformers);
+            var emitResult = ts.emitFiles(emitResolver, getEmitHost(writeFileCallback), sourceFile, // TODO: GH#18217
+            emitOnlyDtsFiles, transformers, customTransformers && customTransformers.afterDeclarations);
+            ts.performance.mark("afterEmit");
+            ts.performance.measure("Emit", "beforeEmit", "afterEmit");
+            return emitResult;
+        }
+        function getSourceFile(fileName) {
+            return getSourceFileByPath(toPath(fileName));
+        }
+        function getSourceFileByPath(path) {
+            return filesByName.get(path);
+        }
+        function getDiagnosticsHelper(sourceFile, getDiagnostics, cancellationToken) {
+            if (sourceFile) {
+                return getDiagnostics(sourceFile, cancellationToken);
+            }
+            return ts.sortAndDeduplicateDiagnostics(ts.flatMap(program.getSourceFiles(), function (sourceFile) {
+                if (cancellationToken) {
+                    cancellationToken.throwIfCancellationRequested();
+                }
+                return getDiagnostics(sourceFile, cancellationToken);
+            }));
+        }
+        function getSyntacticDiagnostics(sourceFile, cancellationToken) {
+            return getDiagnosticsHelper(sourceFile, getSyntacticDiagnosticsForFile, cancellationToken);
+        }
+        function getSemanticDiagnostics(sourceFile, cancellationToken) {
+            return getDiagnosticsHelper(sourceFile, getSemanticDiagnosticsForFile, cancellationToken);
+        }
+        function getDeclarationDiagnostics(sourceFile, cancellationToken) {
+            var options = program.getCompilerOptions();
+            // collect diagnostics from the program only once if either no source file was specified or out/outFile is set (bundled emit)
+            if (!sourceFile || options.out || options.outFile) {
+                return getDeclarationDiagnosticsWorker(sourceFile, cancellationToken);
+            }
+            else {
+                return getDiagnosticsHelper(sourceFile, getDeclarationDiagnosticsForFile, cancellationToken);
+            }
+        }
+        function getSyntacticDiagnosticsForFile(sourceFile) {
+            // For JavaScript files, we report semantic errors for using TypeScript-only
+            // constructs from within a JavaScript file as syntactic errors.
+            if (ts.isSourceFileJavaScript(sourceFile)) {
+                if (!sourceFile.additionalSyntacticDiagnostics) {
+                    sourceFile.additionalSyntacticDiagnostics = getJavaScriptSyntacticDiagnosticsForFile(sourceFile);
+                }
+                return ts.concatenate(sourceFile.additionalSyntacticDiagnostics, sourceFile.parseDiagnostics);
+            }
+            return sourceFile.parseDiagnostics;
+        }
+        function runWithCancellationToken(func) {
+            try {
+                return func();
+            }
+            catch (e) {
+                if (e instanceof ts.OperationCanceledException) {
+                    // We were canceled while performing the operation.  Because our type checker
+                    // might be a bad state, we need to throw it away.
+                    //
+                    // Note: we are overly aggressive here.  We do not actually *have* to throw away
+                    // the "noDiagnosticsTypeChecker".  However, for simplicity, i'd like to keep
+                    // the lifetimes of these two TypeCheckers the same.  Also, we generally only
+                    // cancel when the user has made a change anyways.  And, in that case, we (the
+                    // program instance) will get thrown away anyways.  So trying to keep one of
+                    // these type checkers alive doesn't serve much purpose.
+                    noDiagnosticsTypeChecker = undefined;
+                    diagnosticsProducingTypeChecker = undefined;
+                }
+                throw e;
+            }
+        }
+        function getSemanticDiagnosticsForFile(sourceFile, cancellationToken) {
+            return getAndCacheDiagnostics(sourceFile, cancellationToken, cachedSemanticDiagnosticsForFile, getSemanticDiagnosticsForFileNoCache);
+        }
+        function getSemanticDiagnosticsForFileNoCache(sourceFile, cancellationToken) {
+            return runWithCancellationToken(function () {
+                // If skipLibCheck is enabled, skip reporting errors if file is a declaration file.
+                // If skipDefaultLibCheck is enabled, skip reporting errors if file contains a
+                // '/// <reference no-default-lib="true"/>' directive.
+                if (options.skipLibCheck && sourceFile.isDeclarationFile || options.skipDefaultLibCheck && sourceFile.hasNoDefaultLib) {
+                    return ts.emptyArray;
+                }
+                var typeChecker = getDiagnosticsProducingTypeChecker();
+                ts.Debug.assert(!!sourceFile.bindDiagnostics);
+                var isCheckJs = ts.isCheckJsEnabledForFile(sourceFile, options);
+                // By default, only type-check .ts, .tsx, 'Deferred' and 'External' files (external files are added by plugins)
+                var includeBindAndCheckDiagnostics = sourceFile.scriptKind === 3 /* TS */ || sourceFile.scriptKind === 4 /* TSX */ ||
+                    sourceFile.scriptKind === 5 /* External */ || isCheckJs || sourceFile.scriptKind === 7 /* Deferred */;
+                var bindDiagnostics = includeBindAndCheckDiagnostics ? sourceFile.bindDiagnostics : ts.emptyArray;
+                var checkDiagnostics = includeBindAndCheckDiagnostics ? typeChecker.getDiagnostics(sourceFile, cancellationToken) : ts.emptyArray;
+                var fileProcessingDiagnosticsInFile = fileProcessingDiagnostics.getDiagnostics(sourceFile.fileName);
+                var programDiagnosticsInFile = programDiagnostics.getDiagnostics(sourceFile.fileName);
+                var diagnostics;
+                for (var _i = 0, _a = [bindDiagnostics, checkDiagnostics, fileProcessingDiagnosticsInFile, programDiagnosticsInFile, isCheckJs ? sourceFile.jsDocDiagnostics : undefined]; _i < _a.length; _i++) {
+                    var diags = _a[_i];
+                    if (diags) {
+                        for (var _b = 0, diags_1 = diags; _b < diags_1.length; _b++) {
+                            var diag = diags_1[_b];
+                            if (shouldReportDiagnostic(diag)) {
+                                diagnostics = ts.append(diagnostics, diag);
+                            }
+                        }
+                    }
+                }
+                return diagnostics;
+            });
+        }
+        function getSuggestionDiagnostics(sourceFile, cancellationToken) {
+            return runWithCancellationToken(function () {
+                return getDiagnosticsProducingTypeChecker().getSuggestionDiagnostics(sourceFile, cancellationToken);
+            });
+        }
+        /**
+         * Skip errors if previous line start with '// @ts-ignore' comment, not counting non-empty non-comment lines
+         */
+        function shouldReportDiagnostic(diagnostic) {
+            var file = diagnostic.file, start = diagnostic.start;
+            if (file) {
+                var lineStarts = ts.getLineStarts(file);
+                var line = ts.computeLineAndCharacterOfPosition(lineStarts, start).line; // TODO: GH#18217
+                while (line > 0) {
+                    var previousLineText = file.text.slice(lineStarts[line - 1], lineStarts[line]);
+                    var result = ignoreDiagnosticCommentRegEx.exec(previousLineText);
+                    if (!result) {
+                        // non-empty line
+                        return true;
+                    }
+                    if (result[3]) {
+                        // @ts-ignore
+                        return false;
+                    }
+                    line--;
+                }
+            }
+            return true;
+        }
+        function getJavaScriptSyntacticDiagnosticsForFile(sourceFile) {
+            return runWithCancellationToken(function () {
+                var diagnostics = [];
+                var parent = sourceFile;
+                walk(sourceFile);
+                return diagnostics;
+                function walk(node) {
+                    // Return directly from the case if the given node doesnt want to visit each child
+                    // Otherwise break to visit each child
+                    switch (parent.kind) {
+                        case 149 /* Parameter */:
+                        case 152 /* PropertyDeclaration */:
+                            if (parent.questionToken === node) {
+                                diagnostics.push(createDiagnosticForNode(node, ts.Diagnostics._0_can_only_be_used_in_a_ts_file, "?"));
+                                return;
+                            }
+                        // falls through
+                        case 154 /* MethodDeclaration */:
+                        case 153 /* MethodSignature */:
+                        case 155 /* Constructor */:
+                        case 156 /* GetAccessor */:
+                        case 157 /* SetAccessor */:
+                        case 192 /* FunctionExpression */:
+                        case 234 /* FunctionDeclaration */:
+                        case 193 /* ArrowFunction */:
+                        case 232 /* VariableDeclaration */:
+                            // type annotation
+                            if (parent.type === node) {
+                                diagnostics.push(createDiagnosticForNode(node, ts.Diagnostics.types_can_only_be_used_in_a_ts_file));
+                                return;
+                            }
+                    }
+                    switch (node.kind) {
+                        case 243 /* ImportEqualsDeclaration */:
+                            diagnostics.push(createDiagnosticForNode(node, ts.Diagnostics.import_can_only_be_used_in_a_ts_file));
+                            return;
+                        case 249 /* ExportAssignment */:
+                            if (node.isExportEquals) {
+                                diagnostics.push(createDiagnosticForNode(node, ts.Diagnostics.export_can_only_be_used_in_a_ts_file));
+                                return;
+                            }
+                            break;
+                        case 268 /* HeritageClause */:
+                            var heritageClause = node;
+                            if (heritageClause.token === 108 /* ImplementsKeyword */) {
+                                diagnostics.push(createDiagnosticForNode(node, ts.Diagnostics.implements_clauses_can_only_be_used_in_a_ts_file));
+                                return;
+                            }
+                            break;
+                        case 236 /* InterfaceDeclaration */:
+                            diagnostics.push(createDiagnosticForNode(node, ts.Diagnostics.interface_declarations_can_only_be_used_in_a_ts_file));
+                            return;
+                        case 239 /* ModuleDeclaration */:
+                            diagnostics.push(createDiagnosticForNode(node, ts.Diagnostics.module_declarations_can_only_be_used_in_a_ts_file));
+                            return;
+                        case 237 /* TypeAliasDeclaration */:
+                            diagnostics.push(createDiagnosticForNode(node, ts.Diagnostics.type_aliases_can_only_be_used_in_a_ts_file));
+                            return;
+                        case 238 /* EnumDeclaration */:
+                            diagnostics.push(createDiagnosticForNode(node, ts.Diagnostics.enum_declarations_can_only_be_used_in_a_ts_file));
+                            return;
+                        case 209 /* NonNullExpression */:
+                            diagnostics.push(createDiagnosticForNode(node, ts.Diagnostics.non_null_assertions_can_only_be_used_in_a_ts_file));
+                            return;
+                        case 208 /* AsExpression */:
+                            diagnostics.push(createDiagnosticForNode(node.type, ts.Diagnostics.type_assertion_expressions_can_only_be_used_in_a_ts_file));
+                            return;
+                        case 190 /* TypeAssertionExpression */:
+                            ts.Debug.fail(); // Won't parse these in a JS file anyway, as they are interpreted as JSX.
+                    }
+                    var prevParent = parent;
+                    parent = node;
+                    ts.forEachChild(node, walk, walkArray);
+                    parent = prevParent;
+                }
+                function walkArray(nodes) {
+                    if (parent.decorators === nodes && !options.experimentalDecorators) {
+                        diagnostics.push(createDiagnosticForNode(parent, ts.Diagnostics.Experimental_support_for_decorators_is_a_feature_that_is_subject_to_change_in_a_future_release_Set_the_experimentalDecorators_option_to_remove_this_warning));
+                    }
+                    switch (parent.kind) {
+                        case 235 /* ClassDeclaration */:
+                        case 154 /* MethodDeclaration */:
+                        case 153 /* MethodSignature */:
+                        case 155 /* Constructor */:
+                        case 156 /* GetAccessor */:
+                        case 157 /* SetAccessor */:
+                        case 192 /* FunctionExpression */:
+                        case 234 /* FunctionDeclaration */:
+                        case 193 /* ArrowFunction */:
+                            // Check type parameters
+                            if (nodes === parent.typeParameters) {
+                                diagnostics.push(createDiagnosticForNodeArray(nodes, ts.Diagnostics.type_parameter_declarations_can_only_be_used_in_a_ts_file));
+                                return;
+                            }
+                        // falls through
+                        case 214 /* VariableStatement */:
+                            // Check modifiers
+                            if (nodes === parent.modifiers) {
+                                return checkModifiers(nodes, parent.kind === 214 /* VariableStatement */);
+                            }
+                            break;
+                        case 152 /* PropertyDeclaration */:
+                            // Check modifiers of property declaration
+                            if (nodes === parent.modifiers) {
+                                for (var _i = 0, _a = nodes; _i < _a.length; _i++) {
+                                    var modifier = _a[_i];
+                                    if (modifier.kind !== 115 /* StaticKeyword */) {
+                                        diagnostics.push(createDiagnosticForNode(modifier, ts.Diagnostics._0_can_only_be_used_in_a_ts_file, ts.tokenToString(modifier.kind)));
+                                    }
+                                }
+                                return;
+                            }
+                            break;
+                        case 149 /* Parameter */:
+                            // Check modifiers of parameter declaration
+                            if (nodes === parent.modifiers) {
+                                diagnostics.push(createDiagnosticForNodeArray(nodes, ts.Diagnostics.parameter_modifiers_can_only_be_used_in_a_ts_file));
+                                return;
+                            }
+                            break;
+                        case 187 /* CallExpression */:
+                        case 188 /* NewExpression */:
+                        case 207 /* ExpressionWithTypeArguments */:
+                        case 256 /* JsxSelfClosingElement */:
+                        case 257 /* JsxOpeningElement */:
+                            // Check type arguments
+                            if (nodes === parent.typeArguments) {
+                                diagnostics.push(createDiagnosticForNodeArray(nodes, ts.Diagnostics.type_arguments_can_only_be_used_in_a_ts_file));
+                                return;
+                            }
+                            break;
+                    }
+                    for (var _b = 0, nodes_6 = nodes; _b < nodes_6.length; _b++) {
+                        var node = nodes_6[_b];
+                        walk(node);
+                    }
+                }
+                function checkModifiers(modifiers, isConstValid) {
+                    for (var _i = 0, modifiers_1 = modifiers; _i < modifiers_1.length; _i++) {
+                        var modifier = modifiers_1[_i];
+                        switch (modifier.kind) {
+                            case 76 /* ConstKeyword */:
+                                if (isConstValid) {
+                                    continue;
+                                }
+                            // to report error,
+                            // falls through
+                            case 114 /* PublicKeyword */:
+                            case 112 /* PrivateKeyword */:
+                            case 113 /* ProtectedKeyword */:
+                            case 132 /* ReadonlyKeyword */:
+                            case 124 /* DeclareKeyword */:
+                            case 117 /* AbstractKeyword */:
+                                diagnostics.push(createDiagnosticForNode(modifier, ts.Diagnostics._0_can_only_be_used_in_a_ts_file, ts.tokenToString(modifier.kind)));
+                                break;
+                            // These are all legal modifiers.
+                            case 115 /* StaticKeyword */:
+                            case 84 /* ExportKeyword */:
+                            case 79 /* DefaultKeyword */:
+                        }
+                    }
+                }
+                function createDiagnosticForNodeArray(nodes, message, arg0, arg1, arg2) {
+                    var start = nodes.pos;
+                    return ts.createFileDiagnostic(sourceFile, start, nodes.end - start, message, arg0, arg1, arg2);
+                }
+                // Since these are syntactic diagnostics, parent might not have been set
+                // this means the sourceFile cannot be infered from the node
+                function createDiagnosticForNode(node, message, arg0, arg1, arg2) {
+                    return ts.createDiagnosticForNodeInSourceFile(sourceFile, node, message, arg0, arg1, arg2);
+                }
+            });
+        }
+        function getDeclarationDiagnosticsWorker(sourceFile, cancellationToken) {
+            return getAndCacheDiagnostics(sourceFile, cancellationToken, cachedDeclarationDiagnosticsForFile, getDeclarationDiagnosticsForFileNoCache);
+        }
+        function getDeclarationDiagnosticsForFileNoCache(sourceFile, cancellationToken) {
+            return runWithCancellationToken(function () {
+                var resolver = getDiagnosticsProducingTypeChecker().getEmitResolver(sourceFile, cancellationToken);
+                // Don't actually write any files since we're just getting diagnostics.
+                return ts.getDeclarationDiagnostics(getEmitHost(ts.noop), resolver, sourceFile);
+            });
+        }
+        function getAndCacheDiagnostics(sourceFile, cancellationToken, cache, getDiagnostics) {
+            var cachedResult = sourceFile
+                ? cache.perFile && cache.perFile.get(sourceFile.path)
+                : cache.allDiagnostics;
+            if (cachedResult) {
+                return cachedResult;
+            }
+            var result = getDiagnostics(sourceFile, cancellationToken) || ts.emptyArray; // TODO: GH#18217
+            if (sourceFile) {
+                if (!cache.perFile) {
+                    cache.perFile = ts.createMap();
+                }
+                cache.perFile.set(sourceFile.path, result);
+            }
+            else {
+                cache.allDiagnostics = result;
+            }
+            return result;
+        }
+        function getDeclarationDiagnosticsForFile(sourceFile, cancellationToken) {
+            return sourceFile.isDeclarationFile ? [] : getDeclarationDiagnosticsWorker(sourceFile, cancellationToken);
+        }
+        function getOptionsDiagnostics() {
+            return ts.sortAndDeduplicateDiagnostics(ts.concatenate(fileProcessingDiagnostics.getGlobalDiagnostics(), ts.concatenate(programDiagnostics.getGlobalDiagnostics(), options.configFile ? programDiagnostics.getDiagnostics(options.configFile.fileName) : [])));
+        }
+        function getGlobalDiagnostics() {
+            return ts.sortAndDeduplicateDiagnostics(getDiagnosticsProducingTypeChecker().getGlobalDiagnostics().slice());
+        }
+        function getConfigFileParsingDiagnostics() {
+            return configFileParsingDiagnostics || ts.emptyArray;
+        }
+        function processRootFile(fileName, isDefaultLib, ignoreNoDefaultLib) {
+            processSourceFile(ts.normalizePath(fileName), isDefaultLib, ignoreNoDefaultLib, /*packageId*/ undefined);
+        }
+        function fileReferenceIsEqualTo(a, b) {
+            return a.fileName === b.fileName;
+        }
+        function moduleNameIsEqualTo(a, b) {
+            return a.kind === 71 /* Identifier */
+                ? b.kind === 71 /* Identifier */ && a.escapedText === b.escapedText
+                : b.kind === 9 /* StringLiteral */ && a.text === b.text;
+        }
+        function collectExternalModuleReferences(file) {
+            if (file.imports) {
+                return;
+            }
+            var isJavaScriptFile = ts.isSourceFileJavaScript(file);
+            var isExternalModuleFile = ts.isExternalModule(file);
+            // file.imports may not be undefined if there exists dynamic import
+            var imports;
+            var moduleAugmentations;
+            var ambientModules;
+            // If we are importing helpers, we need to add a synthetic reference to resolve the
+            // helpers library.
+            if (options.importHelpers
+                && (options.isolatedModules || isExternalModuleFile)
+                && !file.isDeclarationFile) {
+                // synthesize 'import "tslib"' declaration
+                var externalHelpersModuleReference = ts.createLiteral(ts.externalHelpersModuleNameText);
+                var importDecl = ts.createImportDeclaration(/*decorators*/ undefined, /*modifiers*/ undefined, /*importClause*/ undefined, externalHelpersModuleReference);
+                ts.addEmitFlags(importDecl, 67108864 /* NeverApplyImportHelper */);
+                externalHelpersModuleReference.parent = importDecl;
+                importDecl.parent = file;
+                imports = [externalHelpersModuleReference];
+            }
+            for (var _i = 0, _a = file.statements; _i < _a.length; _i++) {
+                var node = _a[_i];
+                collectModuleReferences(node, /*inAmbientModule*/ false);
+                if ((file.flags & 524288 /* PossiblyContainsDynamicImport */) || isJavaScriptFile) {
+                    collectDynamicImportOrRequireCalls(node);
+                }
+            }
+            if ((file.flags & 524288 /* PossiblyContainsDynamicImport */) || isJavaScriptFile) {
+                collectDynamicImportOrRequireCalls(file.endOfFileToken);
+            }
+            file.imports = imports || ts.emptyArray;
+            file.moduleAugmentations = moduleAugmentations || ts.emptyArray;
+            file.ambientModuleNames = ambientModules || ts.emptyArray;
+            return;
+            function collectModuleReferences(node, inAmbientModule) {
+                if (ts.isAnyImportOrReExport(node)) {
+                    var moduleNameExpr = ts.getExternalModuleName(node);
+                    // TypeScript 1.0 spec (April 2014): 12.1.6
+                    // An ExternalImportDeclaration in an AmbientExternalModuleDeclaration may reference other external modules
+                    // only through top - level external module names. Relative external module names are not permitted.
+                    if (moduleNameExpr && ts.isStringLiteral(moduleNameExpr) && moduleNameExpr.text && (!inAmbientModule || !ts.isExternalModuleNameRelative(moduleNameExpr.text))) {
+                        imports = ts.append(imports, moduleNameExpr);
+                    }
+                }
+                else if (ts.isModuleDeclaration(node)) {
+                    if (ts.isAmbientModule(node) && (inAmbientModule || ts.hasModifier(node, 2 /* Ambient */) || file.isDeclarationFile)) {
+                        var nameText = ts.getTextOfIdentifierOrLiteral(node.name);
+                        // Ambient module declarations can be interpreted as augmentations for some existing external modules.
+                        // This will happen in two cases:
+                        // - if current file is external module then module augmentation is a ambient module declaration defined in the top level scope
+                        // - if current file is not external module then module augmentation is an ambient module declaration with non-relative module name
+                        //   immediately nested in top level ambient module declaration .
+                        if (isExternalModuleFile || (inAmbientModule && !ts.isExternalModuleNameRelative(nameText))) {
+                            (moduleAugmentations || (moduleAugmentations = [])).push(node.name);
+                        }
+                        else if (!inAmbientModule) {
+                            if (file.isDeclarationFile) {
+                                // for global .d.ts files record name of ambient module
+                                (ambientModules || (ambientModules = [])).push(nameText);
+                            }
+                            // An AmbientExternalModuleDeclaration declares an external module.
+                            // This type of declaration is permitted only in the global module.
+                            // The StringLiteral must specify a top - level external module name.
+                            // Relative external module names are not permitted
+                            // NOTE: body of ambient module is always a module block, if it exists
+                            var body = node.body;
+                            if (body) {
+                                for (var _i = 0, _a = body.statements; _i < _a.length; _i++) {
+                                    var statement = _a[_i];
+                                    collectModuleReferences(statement, /*inAmbientModule*/ true);
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+            function collectDynamicImportOrRequireCalls(node) {
+                if (ts.isRequireCall(node, /*checkArgumentIsStringLiteralLike*/ true)) {
+                    imports = ts.append(imports, node.arguments[0]);
+                }
+                // we have to check the argument list has length of 1. We will still have to process these even though we have parsing error.
+                else if (ts.isImportCall(node) && node.arguments.length === 1 && ts.isStringLiteralLike(node.arguments[0])) {
+                    imports = ts.append(imports, node.arguments[0]);
+                }
+                else if (ts.isLiteralImportTypeNode(node)) {
+                    imports = ts.append(imports, node.argument.literal);
+                }
+                collectDynamicImportOrRequireCallsForEachChild(node);
+                if (ts.hasJSDocNodes(node)) {
+                    ts.forEach(node.jsDoc, collectDynamicImportOrRequireCallsForEachChild);
+                }
+            }
+            function collectDynamicImportOrRequireCallsForEachChild(node) {
+                ts.forEachChild(node, collectDynamicImportOrRequireCalls);
+            }
+        }
+        function getLibFileFromReference(ref) {
+            var libName = ref.fileName.toLocaleLowerCase();
+            var libFileName = ts.libMap.get(libName);
+            if (libFileName) {
+                return getSourceFile(ts.combinePaths(defaultLibraryPath, libFileName));
+            }
+        }
+        /** This should have similar behavior to 'processSourceFile' without diagnostics or mutation. */
+        function getSourceFileFromReference(referencingFile, ref) {
+            return getSourceFileFromReferenceWorker(resolveTripleslashReference(ref.fileName, referencingFile.fileName), function (fileName) { return filesByName.get(toPath(fileName)); });
+        }
+        function getSourceFileFromReferenceWorker(fileName, getSourceFile, fail, refFile) {
+            if (ts.hasExtension(fileName)) {
+                if (!options.allowNonTsExtensions && !ts.forEach(supportedExtensions, function (extension) { return ts.fileExtensionIs(host.getCanonicalFileName(fileName), extension); })) {
+                    if (fail)
+                        fail(ts.Diagnostics.File_0_has_unsupported_extension_The_only_supported_extensions_are_1, fileName, "'" + supportedExtensions.join("', '") + "'");
+                    return undefined;
+                }
+                var sourceFile = getSourceFile(fileName);
+                if (fail) {
+                    if (!sourceFile) {
+                        var redirect = getProjectReferenceRedirect(fileName);
+                        if (redirect) {
+                            fail(ts.Diagnostics.Output_file_0_has_not_been_built_from_source_file_1, redirect, fileName);
+                        }
+                        else {
+                            fail(ts.Diagnostics.File_0_not_found, fileName);
+                        }
+                    }
+                    else if (refFile && host.getCanonicalFileName(fileName) === host.getCanonicalFileName(refFile.fileName)) {
+                        fail(ts.Diagnostics.A_file_cannot_have_a_reference_to_itself);
+                    }
+                }
+                return sourceFile;
+            }
+            else {
+                var sourceFileNoExtension = options.allowNonTsExtensions && getSourceFile(fileName);
+                if (sourceFileNoExtension)
+                    return sourceFileNoExtension;
+                if (fail && options.allowNonTsExtensions) {
+                    fail(ts.Diagnostics.File_0_not_found, fileName);
+                    return undefined;
+                }
+                var sourceFileWithAddedExtension = ts.forEach(supportedExtensions, function (extension) { return getSourceFile(fileName + extension); });
+                if (fail && !sourceFileWithAddedExtension)
+                    fail(ts.Diagnostics.File_0_not_found, fileName + ".ts" /* Ts */);
+                return sourceFileWithAddedExtension;
+            }
+        }
+        /** This has side effects through `findSourceFile`. */
+        function processSourceFile(fileName, isDefaultLib, ignoreNoDefaultLib, packageId, refFile, refPos, refEnd) {
+            getSourceFileFromReferenceWorker(fileName, function (fileName) { return findSourceFile(fileName, toPath(fileName), isDefaultLib, ignoreNoDefaultLib, refFile, refPos, refEnd, packageId); }, // TODO: GH#18217
+            function (diagnostic) {
+                var args = [];
+                for (var _i = 1; _i < arguments.length; _i++) {
+                    args[_i - 1] = arguments[_i];
+                }
+                fileProcessingDiagnostics.add(refFile !== undefined && refEnd !== undefined && refPos !== undefined
+                    ? ts.createFileDiagnostic.apply(void 0, [refFile, refPos, refEnd - refPos, diagnostic].concat(args)) : ts.createCompilerDiagnostic.apply(void 0, [diagnostic].concat(args)));
+            }, refFile);
+        }
+        function reportFileNamesDifferOnlyInCasingError(fileName, existingFileName, refFile, refPos, refEnd) {
+            if (refFile !== undefined && refPos !== undefined && refEnd !== undefined) {
+                fileProcessingDiagnostics.add(ts.createFileDiagnostic(refFile, refPos, refEnd - refPos, ts.Diagnostics.File_name_0_differs_from_already_included_file_name_1_only_in_casing, fileName, existingFileName));
+            }
+            else {
+                fileProcessingDiagnostics.add(ts.createCompilerDiagnostic(ts.Diagnostics.File_name_0_differs_from_already_included_file_name_1_only_in_casing, fileName, existingFileName));
+            }
+        }
+        function createRedirectSourceFile(redirectTarget, unredirected, fileName, path) {
+            var redirect = Object.create(redirectTarget);
+            redirect.fileName = fileName;
+            redirect.path = path;
+            redirect.redirectInfo = { redirectTarget: redirectTarget, unredirected: unredirected };
+            Object.defineProperties(redirect, {
+                id: {
+                    get: function () { return this.redirectInfo.redirectTarget.id; },
+                    set: function (value) { this.redirectInfo.redirectTarget.id = value; },
+                },
+                symbol: {
+                    get: function () { return this.redirectInfo.redirectTarget.symbol; },
+                    set: function (value) { this.redirectInfo.redirectTarget.symbol = value; },
+                },
+            });
+            return redirect;
+        }
+        // Get source file from normalized fileName
+        function findSourceFile(fileName, path, isDefaultLib, ignoreNoDefaultLib, refFile, refPos, refEnd, packageId) {
+            if (filesByName.has(path)) {
+                var file_1 = filesByName.get(path);
+                // try to check if we've already seen this file but with a different casing in path
+                // NOTE: this only makes sense for case-insensitive file systems
+                if (file_1 && options.forceConsistentCasingInFileNames && ts.getNormalizedAbsolutePath(file_1.fileName, currentDirectory) !== ts.getNormalizedAbsolutePath(fileName, currentDirectory)) {
+                    reportFileNamesDifferOnlyInCasingError(fileName, file_1.fileName, refFile, refPos, refEnd);
+                }
+                // If the file was previously found via a node_modules search, but is now being processed as a root file,
+                // then everything it sucks in may also be marked incorrectly, and needs to be checked again.
+                if (file_1 && sourceFilesFoundSearchingNodeModules.get(file_1.path) && currentNodeModulesDepth === 0) {
+                    sourceFilesFoundSearchingNodeModules.set(file_1.path, false);
+                    if (!options.noResolve) {
+                        processReferencedFiles(file_1, isDefaultLib);
+                        processTypeReferenceDirectives(file_1);
+                    }
+                    processLibReferenceDirectives(file_1);
+                    modulesWithElidedImports.set(file_1.path, false);
+                    processImportedModules(file_1);
+                }
+                // See if we need to reprocess the imports due to prior skipped imports
+                else if (file_1 && modulesWithElidedImports.get(file_1.path)) {
+                    if (currentNodeModulesDepth < maxNodeModuleJsDepth) {
+                        modulesWithElidedImports.set(file_1.path, false);
+                        processImportedModules(file_1);
+                    }
+                }
+                return file_1;
+            }
+            var redirectedPath;
+            if (refFile) {
+                var redirect = getProjectReferenceRedirect(fileName);
+                if (redirect) {
+                    (refFile.redirectedReferences || (refFile.redirectedReferences = [])).push(fileName);
+                    fileName = redirect;
+                    // Once we start redirecting to a file, we can potentially come back to it
+                    // via a back-reference from another file in the .d.ts folder. If that happens we'll
+                    // end up trying to add it to the program *again* because we were tracking it via its
+                    // original (un-redirected) name. So we have to map both the original path and the redirected path
+                    // to the source file we're about to find/create
+                    redirectedPath = toPath(redirect);
+                }
+            }
+            // We haven't looked for this file, do so now and cache result
+            var file = host.getSourceFile(fileName, options.target, function (hostErrorMessage) {
+                if (refFile !== undefined && refPos !== undefined && refEnd !== undefined) {
+                    fileProcessingDiagnostics.add(ts.createFileDiagnostic(refFile, refPos, refEnd - refPos, ts.Diagnostics.Cannot_read_file_0_Colon_1, fileName, hostErrorMessage));
+                }
+                else {
+                    fileProcessingDiagnostics.add(ts.createCompilerDiagnostic(ts.Diagnostics.Cannot_read_file_0_Colon_1, fileName, hostErrorMessage));
+                }
+            }, shouldCreateNewSourceFile);
+            if (packageId) {
+                var packageIdKey = ts.packageIdToString(packageId);
+                var fileFromPackageId = packageIdToSourceFile.get(packageIdKey);
+                if (fileFromPackageId) {
+                    // Some other SourceFile already exists with this package name and version.
+                    // Instead of creating a duplicate, just redirect to the existing one.
+                    var dupFile = createRedirectSourceFile(fileFromPackageId, file, fileName, path); // TODO: GH#18217
+                    redirectTargetsSet.set(fileFromPackageId.path, true);
+                    filesByName.set(path, dupFile);
+                    sourceFileToPackageName.set(path, packageId.name);
+                    processingOtherFiles.push(dupFile);
+                    return dupFile;
+                }
+                else if (file) {
+                    // This is the first source file to have this packageId.
+                    packageIdToSourceFile.set(packageIdKey, file);
+                    sourceFileToPackageName.set(path, packageId.name);
+                }
+            }
+            filesByName.set(path, file);
+            if (redirectedPath) {
+                filesByName.set(redirectedPath, file);
+            }
+            if (file) {
+                sourceFilesFoundSearchingNodeModules.set(path, currentNodeModulesDepth > 0);
+                file.path = path;
+                file.resolvedPath = toPath(fileName);
+                if (host.useCaseSensitiveFileNames()) {
+                    var pathLowerCase = path.toLowerCase();
+                    // for case-sensitive file systems check if we've already seen some file with similar filename ignoring case
+                    var existingFile = filesByNameIgnoreCase.get(pathLowerCase);
+                    if (existingFile) {
+                        reportFileNamesDifferOnlyInCasingError(fileName, existingFile.fileName, refFile, refPos, refEnd);
+                    }
+                    else {
+                        filesByNameIgnoreCase.set(pathLowerCase, file);
+                    }
+                }
+                skipDefaultLib = skipDefaultLib || (file.hasNoDefaultLib && !ignoreNoDefaultLib);
+                if (!options.noResolve) {
+                    processReferencedFiles(file, isDefaultLib);
+                    processTypeReferenceDirectives(file);
+                }
+                processLibReferenceDirectives(file);
+                // always process imported modules to record module name resolutions
+                processImportedModules(file);
+                if (isDefaultLib) {
+                    processingDefaultLibFiles.push(file);
+                }
+                else {
+                    processingOtherFiles.push(file);
+                }
+            }
+            return file;
+        }
+        function getProjectReferenceRedirect(fileName) {
+            var path = toPath(fileName);
+            // If this file is produced by a referenced project, we need to rewrite it to
+            // look in the output folder of the referenced project rather than the input
+            var normalized = ts.getNormalizedAbsolutePath(fileName, path);
+            var result;
+            projectReferenceRedirects.forEach(function (v, k) {
+                if (result !== undefined) {
+                    return undefined;
+                }
+                if (normalized.indexOf(k) === 0) {
+                    result = ts.changeExtension(fileName.replace(k, v), ".d.ts");
+                }
+            });
+            return result;
+        }
+        function processReferencedFiles(file, isDefaultLib) {
+            ts.forEach(file.referencedFiles, function (ref) {
+                var referencedFileName = resolveTripleslashReference(ref.fileName, file.fileName);
+                processSourceFile(referencedFileName, isDefaultLib, /*ignoreNoDefaultLib*/ false, /*packageId*/ undefined, file, ref.pos, ref.end);
+            });
+        }
+        function processTypeReferenceDirectives(file) {
+            // We lower-case all type references because npm automatically lowercases all packages. See GH#9824.
+            var typeDirectives = ts.map(file.typeReferenceDirectives, function (ref) { return ref.fileName.toLocaleLowerCase(); });
+            if (!typeDirectives) {
+                return;
+            }
+            var resolutions = resolveTypeReferenceDirectiveNamesWorker(typeDirectives, file.fileName);
+            for (var i = 0; i < typeDirectives.length; i++) {
+                var ref = file.typeReferenceDirectives[i];
+                var resolvedTypeReferenceDirective = resolutions[i];
+                // store resolved type directive on the file
+                var fileName = ref.fileName.toLocaleLowerCase();
+                ts.setResolvedTypeReferenceDirective(file, fileName, resolvedTypeReferenceDirective);
+                processTypeReferenceDirective(fileName, resolvedTypeReferenceDirective, file, ref.pos, ref.end);
+            }
+        }
+        function processTypeReferenceDirective(typeReferenceDirective, resolvedTypeReferenceDirective, refFile, refPos, refEnd) {
+            // If we already found this library as a primary reference - nothing to do
+            var previousResolution = resolvedTypeReferenceDirectives.get(typeReferenceDirective);
+            if (previousResolution && previousResolution.primary) {
+                return;
+            }
+            var saveResolution = true;
+            if (resolvedTypeReferenceDirective) {
+                if (resolvedTypeReferenceDirective.primary) {
+                    // resolved from the primary path
+                    processSourceFile(resolvedTypeReferenceDirective.resolvedFileName, /*isDefaultLib*/ false, /*ignoreNoDefaultLib*/ false, resolvedTypeReferenceDirective.packageId, refFile, refPos, refEnd); // TODO: GH#18217
+                }
+                else {
+                    // If we already resolved to this file, it must have been a secondary reference. Check file contents
+                    // for sameness and possibly issue an error
+                    if (previousResolution) {
+                        // Don't bother reading the file again if it's the same file.
+                        if (resolvedTypeReferenceDirective.resolvedFileName !== previousResolution.resolvedFileName) {
+                            var otherFileText = host.readFile(resolvedTypeReferenceDirective.resolvedFileName);
+                            if (otherFileText !== getSourceFile(previousResolution.resolvedFileName).text) {
+                                fileProcessingDiagnostics.add(createDiagnostic(refFile, refPos, refEnd, // TODO: GH#18217
+                                ts.Diagnostics.Conflicting_definitions_for_0_found_at_1_and_2_Consider_installing_a_specific_version_of_this_library_to_resolve_the_conflict, typeReferenceDirective, resolvedTypeReferenceDirective.resolvedFileName, previousResolution.resolvedFileName));
+                            }
+                        }
+                        // don't overwrite previous resolution result
+                        saveResolution = false;
+                    }
+                    else {
+                        // First resolution of this library
+                        processSourceFile(resolvedTypeReferenceDirective.resolvedFileName, /*isDefaultLib*/ false, /*ignoreNoDefaultLib*/ false, resolvedTypeReferenceDirective.packageId, refFile, refPos, refEnd);
+                    }
+                }
+            }
+            else {
+                fileProcessingDiagnostics.add(createDiagnostic(refFile, refPos, refEnd, ts.Diagnostics.Cannot_find_type_definition_file_for_0, typeReferenceDirective)); // TODO: GH#18217
+            }
+            if (saveResolution) {
+                resolvedTypeReferenceDirectives.set(typeReferenceDirective, resolvedTypeReferenceDirective);
+            }
+        }
+        function processLibReferenceDirectives(file) {
+            ts.forEach(file.libReferenceDirectives, function (libReference) {
+                var libName = libReference.fileName.toLocaleLowerCase();
+                var libFileName = ts.libMap.get(libName);
+                if (libFileName) {
+                    // we ignore any 'no-default-lib' reference set on this file.
+                    processRootFile(ts.combinePaths(defaultLibraryPath, libFileName), /*isDefaultLib*/ true, /*ignoreNoDefaultLib*/ true);
+                }
+                else {
+                    var unqualifiedLibName = ts.removeSuffix(ts.removePrefix(libName, "lib."), ".d.ts");
+                    var suggestion = ts.getSpellingSuggestion(unqualifiedLibName, ts.libs, ts.identity);
+                    var message = suggestion ? ts.Diagnostics.Cannot_find_lib_definition_for_0_Did_you_mean_1 : ts.Diagnostics.Cannot_find_lib_definition_for_0;
+                    fileProcessingDiagnostics.add(createDiagnostic(file, libReference.pos, libReference.end, message, libName, suggestion));
+                }
+            });
+        }
+        function createDiagnostic(refFile, refPos, refEnd, message) {
+            var args = [];
+            for (var _i = 4; _i < arguments.length; _i++) {
+                args[_i - 4] = arguments[_i];
+            }
+            if (refFile === undefined || refPos === undefined || refEnd === undefined) {
+                return ts.createCompilerDiagnostic.apply(void 0, [message].concat(args));
+            }
+            else {
+                return ts.createFileDiagnostic.apply(void 0, [refFile, refPos, refEnd - refPos, message].concat(args));
+            }
+        }
+        function getCanonicalFileName(fileName) {
+            return host.getCanonicalFileName(fileName);
+        }
+        function processImportedModules(file) {
+            collectExternalModuleReferences(file);
+            if (file.imports.length || file.moduleAugmentations.length) {
+                // Because global augmentation doesn't have string literal name, we can check for global augmentation as such.
+                var moduleNames = getModuleNames(file);
+                var oldProgramState = { program: oldProgram, oldSourceFile: oldProgram && oldProgram.getSourceFile(file.fileName), modifiedFilePaths: modifiedFilePaths };
+                var resolutions = resolveModuleNamesReusingOldState(moduleNames, ts.getNormalizedAbsolutePath(file.fileName, currentDirectory), file, oldProgramState);
+                ts.Debug.assert(resolutions.length === moduleNames.length);
+                for (var i = 0; i < moduleNames.length; i++) {
+                    var resolution = resolutions[i];
+                    ts.setResolvedModule(file, moduleNames[i], resolution);
+                    if (!resolution) {
+                        continue;
+                    }
+                    var isFromNodeModulesSearch = resolution.isExternalLibraryImport;
+                    var isJsFile = !ts.resolutionExtensionIsTypeScriptOrJson(resolution.extension);
+                    var isJsFileFromNodeModules = isFromNodeModulesSearch && isJsFile;
+                    var resolvedFileName = resolution.resolvedFileName;
+                    if (isFromNodeModulesSearch) {
+                        currentNodeModulesDepth++;
+                    }
+                    // add file to program only if:
+                    // - resolution was successful
+                    // - noResolve is falsy
+                    // - module name comes from the list of imports
+                    // - it's not a top level JavaScript module that exceeded the search max
+                    var elideImport = isJsFileFromNodeModules && currentNodeModulesDepth > maxNodeModuleJsDepth;
+                    // Don't add the file if it has a bad extension (e.g. 'tsx' if we don't have '--allowJs')
+                    // This may still end up being an untyped module -- the file won't be included but imports will be allowed.
+                    var shouldAddFile = resolvedFileName
+                        && !getResolutionDiagnostic(options, resolution)
+                        && !options.noResolve
+                        && i < file.imports.length
+                        && !elideImport
+                        && !(isJsFile && !options.allowJs)
+                        && (ts.isInJavaScriptFile(file.imports[i]) || !(file.imports[i].flags & 2097152 /* JSDoc */));
+                    if (elideImport) {
+                        modulesWithElidedImports.set(file.path, true);
+                    }
+                    else if (shouldAddFile) {
+                        var path = toPath(resolvedFileName);
+                        var pos = ts.skipTrivia(file.text, file.imports[i].pos);
+                        findSourceFile(resolvedFileName, path, /*isDefaultLib*/ false, /*ignoreNoDefaultLib*/ false, file, pos, file.imports[i].end, resolution.packageId);
+                    }
+                    if (isFromNodeModulesSearch) {
+                        currentNodeModulesDepth--;
+                    }
+                }
+            }
+            else {
+                // no imports - drop cached module resolutions
+                file.resolvedModules = undefined;
+            }
+        }
+        function computeCommonSourceDirectory(sourceFiles) {
+            var fileNames = [];
+            for (var _i = 0, sourceFiles_2 = sourceFiles; _i < sourceFiles_2.length; _i++) {
+                var file = sourceFiles_2[_i];
+                if (!file.isDeclarationFile) {
+                    fileNames.push(file.fileName);
+                }
+            }
+            return computeCommonSourceDirectoryOfFilenames(fileNames, currentDirectory, getCanonicalFileName);
+        }
+        function checkSourceFilesBelongToPath(sourceFiles, rootDirectory) {
+            var allFilesBelongToPath = true;
+            if (sourceFiles) {
+                var absoluteRootDirectoryPath = host.getCanonicalFileName(ts.getNormalizedAbsolutePath(rootDirectory, currentDirectory));
+                for (var _i = 0, sourceFiles_3 = sourceFiles; _i < sourceFiles_3.length; _i++) {
+                    var sourceFile = sourceFiles_3[_i];
+                    if (!sourceFile.isDeclarationFile) {
+                        var absoluteSourceFilePath = host.getCanonicalFileName(ts.getNormalizedAbsolutePath(sourceFile.fileName, currentDirectory));
+                        if (absoluteSourceFilePath.indexOf(absoluteRootDirectoryPath) !== 0) {
+                            programDiagnostics.add(ts.createCompilerDiagnostic(ts.Diagnostics.File_0_is_not_under_rootDir_1_rootDir_is_expected_to_contain_all_source_files, sourceFile.fileName, options.rootDir));
+                            allFilesBelongToPath = false;
+                        }
+                    }
+                }
+            }
+            return allFilesBelongToPath;
+        }
+        function parseProjectReferenceConfigFile(ref) {
+            // The actual filename (i.e. add "/tsconfig.json" if necessary)
+            var refPath = resolveProjectReferencePath(host, ref); // TODO: GH#18217
+            // An absolute path pointing to the containing directory of the config file
+            var basePath = ts.getNormalizedAbsolutePath(ts.getDirectoryPath(refPath), host.getCurrentDirectory());
+            var sourceFile = host.getSourceFile(refPath, 100 /* JSON */);
+            if (sourceFile === undefined) {
+                return undefined;
+            }
+            var commandLine = ts.parseJsonSourceFileConfigFileContent(sourceFile, configParsingHost, basePath, /*existingOptions*/ undefined, refPath);
+            return { commandLine: commandLine, sourceFile: sourceFile };
+        }
+        function addProjectReferenceRedirects(referencedProject, target) {
+            var rootDir = ts.normalizePath(referencedProject.options.rootDir || ts.getDirectoryPath(referencedProject.options.configFilePath)); // TODO: GH#18217
+            target.set(rootDir, getDeclarationOutputDirectory(referencedProject));
+        }
+        function getDeclarationOutputDirectory(proj) {
+            return proj.options.declarationDir ||
+                proj.options.outDir ||
+                ts.getDirectoryPath(proj.options.configFilePath); // TODO: GH#18217
+        }
+        function verifyCompilerOptions() {
+            if (options.strictPropertyInitialization && !options.strictNullChecks) {
+                createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_without_specifying_option_1, "strictPropertyInitialization", "strictNullChecks");
+            }
+            if (options.isolatedModules) {
+                if (options.declaration) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_with_option_1, "declaration", "isolatedModules");
+                }
+                if (options.noEmitOnError) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_with_option_1, "noEmitOnError", "isolatedModules");
+                }
+                if (options.out) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_with_option_1, "out", "isolatedModules");
+                }
+                if (options.outFile) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_with_option_1, "outFile", "isolatedModules");
+                }
+            }
+            if (options.inlineSourceMap) {
+                if (options.sourceMap) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_with_option_1, "sourceMap", "inlineSourceMap");
+                }
+                if (options.mapRoot) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_with_option_1, "mapRoot", "inlineSourceMap");
+                }
+            }
+            if (options.paths && options.baseUrl === undefined) {
+                createDiagnosticForOptionName(ts.Diagnostics.Option_paths_cannot_be_used_without_specifying_baseUrl_option, "paths");
+            }
+            if (options.composite) {
+                if (options.declaration === false) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Composite_projects_may_not_disable_declaration_emit, "declaration");
+                }
+            }
+            if (projectReferences) {
+                for (var i = 0; i < projectReferences.length; i++) {
+                    var ref = projectReferences[i];
+                    var resolvedRefOpts = resolvedProjectReferences[i] && resolvedProjectReferences[i].commandLine.options;
+                    if (resolvedRefOpts === undefined) {
+                        createDiagnosticForReference(i, ts.Diagnostics.File_0_does_not_exist, ref.path);
+                        continue;
+                    }
+                    if (!resolvedRefOpts.composite) {
+                        createDiagnosticForReference(i, ts.Diagnostics.Referenced_project_0_must_have_setting_composite_Colon_true, ref.path);
+                    }
+                    if (ref.prepend) {
+                        if (resolvedRefOpts.outFile) {
+                            if (!host.fileExists(resolvedRefOpts.outFile)) {
+                                createDiagnosticForReference(i, ts.Diagnostics.Output_file_0_from_project_1_does_not_exist, resolvedRefOpts.outFile, ref.path);
+                            }
+                        }
+                        else {
+                            createDiagnosticForReference(i, ts.Diagnostics.Cannot_prepend_project_0_because_it_does_not_have_outFile_set, ref.path);
+                        }
+                    }
+                }
+            }
+            // List of collected files is complete; validate exhautiveness if this is a project with a file list
+            if (options.composite && rootNames.length < files.length) {
+                var normalizedRootNames = rootNames.map(function (r) { return ts.normalizePath(r).toLowerCase(); });
+                var sourceFiles = files.filter(function (f) { return !f.isDeclarationFile; }).map(function (f) { return ts.normalizePath(f.path).toLowerCase(); });
+                var _loop_11 = function (file) {
+                    if (normalizedRootNames.every(function (r) { return r !== file; })) {
+                        programDiagnostics.add(ts.createCompilerDiagnostic(ts.Diagnostics.File_0_is_not_in_project_file_list_Projects_must_list_all_files_or_use_an_include_pattern, file));
+                    }
+                };
+                for (var _i = 0, sourceFiles_4 = sourceFiles; _i < sourceFiles_4.length; _i++) {
+                    var file = sourceFiles_4[_i];
+                    _loop_11(file);
+                }
+            }
+            if (options.paths) {
+                for (var key in options.paths) {
+                    if (!ts.hasProperty(options.paths, key)) {
+                        continue;
+                    }
+                    if (!ts.hasZeroOrOneAsteriskCharacter(key)) {
+                        createDiagnosticForOptionPaths(/*onKey*/ true, key, ts.Diagnostics.Pattern_0_can_have_at_most_one_Asterisk_character, key);
+                    }
+                    if (ts.isArray(options.paths[key])) {
+                        var len = options.paths[key].length;
+                        if (len === 0) {
+                            createDiagnosticForOptionPaths(/*onKey*/ false, key, ts.Diagnostics.Substitutions_for_pattern_0_shouldn_t_be_an_empty_array, key);
+                        }
+                        for (var i = 0; i < len; i++) {
+                            var subst = options.paths[key][i];
+                            var typeOfSubst = typeof subst;
+                            if (typeOfSubst === "string") {
+                                if (!ts.hasZeroOrOneAsteriskCharacter(subst)) {
+                                    createDiagnosticForOptionPathKeyValue(key, i, ts.Diagnostics.Substitution_0_in_pattern_1_in_can_have_at_most_one_Asterisk_character, subst, key);
+                                }
+                            }
+                            else {
+                                createDiagnosticForOptionPathKeyValue(key, i, ts.Diagnostics.Substitution_0_for_pattern_1_has_incorrect_type_expected_string_got_2, subst, key, typeOfSubst);
+                            }
+                        }
+                    }
+                    else {
+                        createDiagnosticForOptionPaths(/*onKey*/ false, key, ts.Diagnostics.Substitutions_for_pattern_0_should_be_an_array, key);
+                    }
+                }
+            }
+            if (!options.sourceMap && !options.inlineSourceMap) {
+                if (options.inlineSources) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_0_can_only_be_used_when_either_option_inlineSourceMap_or_option_sourceMap_is_provided, "inlineSources");
+                }
+                if (options.sourceRoot) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_0_can_only_be_used_when_either_option_inlineSourceMap_or_option_sourceMap_is_provided, "sourceRoot");
+                }
+            }
+            if (options.out && options.outFile) {
+                createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_with_option_1, "out", "outFile");
+            }
+            if (options.mapRoot && !(options.sourceMap || options.declarationMap)) {
+                // Error to specify --mapRoot without --sourcemap
+                createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_without_specifying_option_1_or_option_2, "mapRoot", "sourceMap", "declarationMap");
+            }
+            if (options.declarationDir) {
+                if (!options.declaration) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_without_specifying_option_1, "declarationDir", "declaration");
+                }
+                if (options.out || options.outFile) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_with_option_1, "declarationDir", options.out ? "out" : "outFile");
+                }
+            }
+            if (options.declarationMap && !options.declaration) {
+                createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_without_specifying_option_1, "declarationMap", "declaration");
+            }
+            if (options.lib && options.noLib) {
+                createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_with_option_1, "lib", "noLib");
+            }
+            if (options.noImplicitUseStrict && ts.getStrictOptionValue(options, "alwaysStrict")) {
+                createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_with_option_1, "noImplicitUseStrict", "alwaysStrict");
+            }
+            var languageVersion = options.target || 0 /* ES3 */;
+            var outFile = options.outFile || options.out;
+            var firstNonAmbientExternalModuleSourceFile = ts.forEach(files, function (f) { return ts.isExternalModule(f) && !f.isDeclarationFile ? f : undefined; });
+            if (options.isolatedModules) {
+                if (options.module === ts.ModuleKind.None && languageVersion < 2 /* ES2015 */) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_isolatedModules_can_only_be_used_when_either_option_module_is_provided_or_option_target_is_ES2015_or_higher, "isolatedModules", "target");
+                }
+                var firstNonExternalModuleSourceFile = ts.forEach(files, function (f) { return !ts.isExternalModule(f) && !f.isDeclarationFile ? f : undefined; });
+                if (firstNonExternalModuleSourceFile) {
+                    var span = ts.getErrorSpanForNode(firstNonExternalModuleSourceFile, firstNonExternalModuleSourceFile);
+                    programDiagnostics.add(ts.createFileDiagnostic(firstNonExternalModuleSourceFile, span.start, span.length, ts.Diagnostics.Cannot_compile_namespaces_when_the_isolatedModules_flag_is_provided));
+                }
+            }
+            else if (firstNonAmbientExternalModuleSourceFile && languageVersion < 2 /* ES2015 */ && options.module === ts.ModuleKind.None) {
+                // We cannot use createDiagnosticFromNode because nodes do not have parents yet
+                var span = ts.getErrorSpanForNode(firstNonAmbientExternalModuleSourceFile, firstNonAmbientExternalModuleSourceFile.externalModuleIndicator);
+                programDiagnostics.add(ts.createFileDiagnostic(firstNonAmbientExternalModuleSourceFile, span.start, span.length, ts.Diagnostics.Cannot_use_imports_exports_or_module_augmentations_when_module_is_none));
+            }
+            // Cannot specify module gen that isn't amd or system with --out
+            if (outFile) {
+                if (options.module && !(options.module === ts.ModuleKind.AMD || options.module === ts.ModuleKind.System)) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Only_amd_and_system_modules_are_supported_alongside_0, options.out ? "out" : "outFile", "module");
+                }
+                else if (options.module === undefined && firstNonAmbientExternalModuleSourceFile) {
+                    var span = ts.getErrorSpanForNode(firstNonAmbientExternalModuleSourceFile, firstNonAmbientExternalModuleSourceFile.externalModuleIndicator);
+                    programDiagnostics.add(ts.createFileDiagnostic(firstNonAmbientExternalModuleSourceFile, span.start, span.length, ts.Diagnostics.Cannot_compile_modules_using_option_0_unless_the_module_flag_is_amd_or_system, options.out ? "out" : "outFile"));
+                }
+            }
+            if (options.resolveJsonModule) {
+                if (ts.getEmitModuleResolutionKind(options) !== ts.ModuleResolutionKind.NodeJs) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_resolveJsonModule_cannot_be_specified_without_node_module_resolution_strategy, "resolveJsonModule");
+                }
+            }
+            // there has to be common source directory if user specified --outdir || --sourceRoot
+            // if user specified --mapRoot, there needs to be common source directory if there would be multiple files being emitted
+            if (options.outDir || // there is --outDir specified
+                options.sourceRoot || // there is --sourceRoot specified
+                options.mapRoot) { // there is --mapRoot specified
+                // Precalculate and cache the common source directory
+                var dir = getCommonSourceDirectory();
+                // If we failed to find a good common directory, but outDir is specified and at least one of our files is on a windows drive/URL/other resource, add a failure
+                if (options.outDir && dir === "" && ts.forEach(files, function (file) { return ts.getRootLength(file.fileName) > 1; })) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Cannot_find_the_common_subdirectory_path_for_the_input_files, "outDir");
+                }
+            }
+            if (!options.noEmit && options.allowJs && options.declaration) {
+                createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_with_option_1, "allowJs", "declaration");
+            }
+            if (options.checkJs && !options.allowJs) {
+                programDiagnostics.add(ts.createCompilerDiagnostic(ts.Diagnostics.Option_0_cannot_be_specified_without_specifying_option_1, "checkJs", "allowJs"));
+            }
+            if (options.emitDeclarationOnly) {
+                if (!options.declaration) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_without_specifying_option_1, "emitDeclarationOnly", "declaration");
+                }
+                if (options.noEmit) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_with_option_1, "emitDeclarationOnly", "noEmit");
+                }
+            }
+            if (options.emitDecoratorMetadata &&
+                !options.experimentalDecorators) {
+                createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_without_specifying_option_1, "emitDecoratorMetadata", "experimentalDecorators");
+            }
+            if (options.jsxFactory) {
+                if (options.reactNamespace) {
+                    createDiagnosticForOptionName(ts.Diagnostics.Option_0_cannot_be_specified_with_option_1, "reactNamespace", "jsxFactory");
+                }
+                if (!ts.parseIsolatedEntityName(options.jsxFactory, languageVersion)) {
+                    createOptionValueDiagnostic("jsxFactory", ts.Diagnostics.Invalid_value_for_jsxFactory_0_is_not_a_valid_identifier_or_qualified_name, options.jsxFactory);
+                }
+            }
+            else if (options.reactNamespace && !ts.isIdentifierText(options.reactNamespace, languageVersion)) {
+                createOptionValueDiagnostic("reactNamespace", ts.Diagnostics.Invalid_value_for_reactNamespace_0_is_not_a_valid_identifier, options.reactNamespace);
+            }
+            // If the emit is enabled make sure that every output file is unique and not overwriting any of the input files
+            if (!options.noEmit && !options.suppressOutputPathCheck) {
+                var emitHost = getEmitHost();
+                var emitFilesSeen_1 = ts.createMap();
+                ts.forEachEmittedFile(emitHost, function (emitFileNames) {
+                    if (!options.emitDeclarationOnly) {
+                        verifyEmitFilePath(emitFileNames.jsFilePath, emitFilesSeen_1);
+                    }
+                    verifyEmitFilePath(emitFileNames.declarationFilePath, emitFilesSeen_1);
+                });
+            }
+            // Verify that all the emit files are unique and don't overwrite input files
+            function verifyEmitFilePath(emitFileName, emitFilesSeen) {
+                if (emitFileName) {
+                    var emitFilePath = toPath(emitFileName);
+                    // Report error if the output overwrites input file
+                    if (filesByName.has(emitFilePath)) {
+                        var chain_2;
+                        if (!options.configFilePath) {
+                            // The program is from either an inferred project or an external project
+                            chain_2 = ts.chainDiagnosticMessages(/*details*/ undefined, ts.Diagnostics.Adding_a_tsconfig_json_file_will_help_organize_projects_that_contain_both_TypeScript_and_JavaScript_files_Learn_more_at_https_Colon_Slash_Slashaka_ms_Slashtsconfig);
+                        }
+                        chain_2 = ts.chainDiagnosticMessages(chain_2, ts.Diagnostics.Cannot_write_file_0_because_it_would_overwrite_input_file, emitFileName);
+                        blockEmittingOfFile(emitFileName, ts.createCompilerDiagnosticFromMessageChain(chain_2));
+                    }
+                    var emitFileKey = !host.useCaseSensitiveFileNames() ? emitFilePath.toLocaleLowerCase() : emitFilePath;
+                    // Report error if multiple files write into same file
+                    if (emitFilesSeen.has(emitFileKey)) {
+                        // Already seen the same emit file - report error
+                        blockEmittingOfFile(emitFileName, ts.createCompilerDiagnostic(ts.Diagnostics.Cannot_write_file_0_because_it_would_be_overwritten_by_multiple_input_files, emitFileName));
+                    }
+                    else {
+                        emitFilesSeen.set(emitFileKey, true);
+                    }
+                }
+            }
+        }
+        function createDiagnosticForOptionPathKeyValue(key, valueIndex, message, arg0, arg1, arg2) {
+            var needCompilerDiagnostic = true;
+            var pathsSyntax = getOptionPathsSyntax();
+            for (var _i = 0, pathsSyntax_1 = pathsSyntax; _i < pathsSyntax_1.length; _i++) {
+                var pathProp = pathsSyntax_1[_i];
+                if (ts.isObjectLiteralExpression(pathProp.initializer)) {
+                    for (var _a = 0, _b = ts.getPropertyAssignment(pathProp.initializer, key); _a < _b.length; _a++) {
+                        var keyProps = _b[_a];
+                        var initializer = keyProps.initializer;
+                        if (ts.isArrayLiteralExpression(initializer) && initializer.elements.length > valueIndex) {
+                            programDiagnostics.add(ts.createDiagnosticForNodeInSourceFile(options.configFile, initializer.elements[valueIndex], message, arg0, arg1, arg2));
+                            needCompilerDiagnostic = false;
+                        }
+                    }
+                }
+            }
+            if (needCompilerDiagnostic) {
+                programDiagnostics.add(ts.createCompilerDiagnostic(message, arg0, arg1, arg2));
+            }
+        }
+        function createDiagnosticForOptionPaths(onKey, key, message, arg0) {
+            var needCompilerDiagnostic = true;
+            var pathsSyntax = getOptionPathsSyntax();
+            for (var _i = 0, pathsSyntax_2 = pathsSyntax; _i < pathsSyntax_2.length; _i++) {
+                var pathProp = pathsSyntax_2[_i];
+                if (ts.isObjectLiteralExpression(pathProp.initializer) &&
+                    createOptionDiagnosticInObjectLiteralSyntax(pathProp.initializer, onKey, key, /*key2*/ undefined, message, arg0)) {
+                    needCompilerDiagnostic = false;
+                }
+            }
+            if (needCompilerDiagnostic) {
+                programDiagnostics.add(ts.createCompilerDiagnostic(message, arg0));
+            }
+        }
+        function getOptionsSyntaxByName(name) {
+            var compilerOptionsObjectLiteralSyntax = getCompilerOptionsObjectLiteralSyntax();
+            if (compilerOptionsObjectLiteralSyntax) {
+                return ts.getPropertyAssignment(compilerOptionsObjectLiteralSyntax, name);
+            }
+            return undefined;
+        }
+        function getOptionPathsSyntax() {
+            return getOptionsSyntaxByName("paths") || ts.emptyArray;
+        }
+        function createDiagnosticForOptionName(message, option1, option2, option3) {
+            createDiagnosticForOption(/*onKey*/ true, option1, option2, message, option1, option2, option3);
+        }
+        function createOptionValueDiagnostic(option1, message, arg0) {
+            createDiagnosticForOption(/*onKey*/ false, option1, /*option2*/ undefined, message, arg0);
+        }
+        function createDiagnosticForReference(index, message, arg0, arg1) {
+            var referencesSyntax = getProjectReferencesSyntax();
+            if (referencesSyntax) {
+                if (createOptionDiagnosticInArrayLiteralSyntax(referencesSyntax, index, message, arg0, arg1)) {
+                    return;
+                }
+            }
+            programDiagnostics.add(ts.createCompilerDiagnostic(message, arg0, arg1));
+        }
+        function createDiagnosticForOption(onKey, option1, option2, message, arg0, arg1, arg2) {
+            var compilerOptionsObjectLiteralSyntax = getCompilerOptionsObjectLiteralSyntax();
+            var needCompilerDiagnostic = !compilerOptionsObjectLiteralSyntax ||
+                !createOptionDiagnosticInObjectLiteralSyntax(compilerOptionsObjectLiteralSyntax, onKey, option1, option2, message, arg0, arg1, arg2);
+            if (needCompilerDiagnostic) {
+                programDiagnostics.add(ts.createCompilerDiagnostic(message, arg0, arg1, arg2));
+            }
+        }
+        function getProjectReferencesSyntax() {
+            if (_referencesArrayLiteralSyntax === undefined) {
+                _referencesArrayLiteralSyntax = null; // tslint:disable-line:no-null-keyword
+                if (options.configFile) {
+                    var jsonObjectLiteral = ts.getTsConfigObjectLiteralExpression(options.configFile); // TODO: GH#18217
+                    for (var _i = 0, _a = ts.getPropertyAssignment(jsonObjectLiteral, "references"); _i < _a.length; _i++) {
+                        var prop = _a[_i];
+                        if (ts.isArrayLiteralExpression(prop.initializer)) {
+                            _referencesArrayLiteralSyntax = prop.initializer;
+                            break;
+                        }
+                    }
+                }
+            }
+            return _referencesArrayLiteralSyntax;
+        }
+        function getCompilerOptionsObjectLiteralSyntax() {
+            if (_compilerOptionsObjectLiteralSyntax === undefined) {
+                _compilerOptionsObjectLiteralSyntax = null; // tslint:disable-line:no-null-keyword
+                var jsonObjectLiteral = ts.getTsConfigObjectLiteralExpression(options.configFile);
+                if (jsonObjectLiteral) {
+                    for (var _i = 0, _a = ts.getPropertyAssignment(jsonObjectLiteral, "compilerOptions"); _i < _a.length; _i++) {
+                        var prop = _a[_i];
+                        if (ts.isObjectLiteralExpression(prop.initializer)) {
+                            _compilerOptionsObjectLiteralSyntax = prop.initializer;
+                            break;
+                        }
+                    }
+                }
+            }
+            return _compilerOptionsObjectLiteralSyntax;
+        }
+        function createOptionDiagnosticInObjectLiteralSyntax(objectLiteral, onKey, key1, key2, message, arg0, arg1, arg2) {
+            var props = ts.getPropertyAssignment(objectLiteral, key1, key2);
+            for (var _i = 0, props_2 = props; _i < props_2.length; _i++) {
+                var prop = props_2[_i];
+                programDiagnostics.add(ts.createDiagnosticForNodeInSourceFile(options.configFile, onKey ? prop.name : prop.initializer, message, arg0, arg1, arg2));
+            }
+            return !!props.length;
+        }
+        function createOptionDiagnosticInArrayLiteralSyntax(arrayLiteral, index, message, arg0, arg1, arg2) {
+            if (arrayLiteral.elements.length <= index) {
+                // Out-of-bounds
+                return false;
+            }
+            programDiagnostics.add(ts.createDiagnosticForNodeInSourceFile(options.configFile, arrayLiteral.elements[index], message, arg0, arg1, arg2));
+            return false; // TODO: GH#18217 This function always returns `false`!`
+        }
+        function blockEmittingOfFile(emitFileName, diag) {
+            hasEmitBlockingDiagnostics.set(toPath(emitFileName), true);
+            programDiagnostics.add(diag);
+        }
+        function isEmittedFile(file) {
+            if (options.noEmit) {
+                return false;
+            }
+            // If this is source file, its not emitted file
+            var filePath = toPath(file);
+            if (getSourceFileByPath(filePath)) {
+                return false;
+            }
+            // If options have --outFile or --out just check that
+            var out = options.outFile || options.out;
+            if (out) {
+                return isSameFile(filePath, out) || isSameFile(filePath, ts.removeFileExtension(out) + ".d.ts" /* Dts */);
+            }
+            // If declarationDir is specified, return if its a file in that directory
+            if (options.declarationDir && ts.containsPath(options.declarationDir, filePath, currentDirectory, !host.useCaseSensitiveFileNames())) {
+                return true;
+            }
+            // If --outDir, check if file is in that directory
+            if (options.outDir) {
+                return ts.containsPath(options.outDir, filePath, currentDirectory, !host.useCaseSensitiveFileNames());
+            }
+            if (ts.fileExtensionIsOneOf(filePath, ts.supportedJavascriptExtensions) || ts.fileExtensionIs(filePath, ".d.ts" /* Dts */)) {
+                // Otherwise just check if sourceFile with the name exists
+                var filePathWithoutExtension = ts.removeFileExtension(filePath);
+                return !!getSourceFileByPath((filePathWithoutExtension + ".ts" /* Ts */)) ||
+                    !!getSourceFileByPath((filePathWithoutExtension + ".tsx" /* Tsx */));
+            }
+            return false;
+        }
+        function isSameFile(file1, file2) {
+            return ts.comparePaths(file1, file2, currentDirectory, !host.useCaseSensitiveFileNames()) === 0 /* EqualTo */;
+        }
+    }
+    ts.createProgram = createProgram;
+    /* @internal */
+    function parseConfigHostFromCompilerHost(host) {
+        return {
+            fileExists: function (f) { return host.fileExists(f); },
+            readDirectory: function (root, extensions, includes, depth) { return host.readDirectory ? host.readDirectory(root, extensions, includes, depth) : []; },
+            readFile: function (f) { return host.readFile(f); },
+            useCaseSensitiveFileNames: host.useCaseSensitiveFileNames(),
+            getCurrentDirectory: function () { return host.getCurrentDirectory(); },
+            onUnRecoverableConfigFileDiagnostic: function () { return undefined; }
+        };
+    }
+    ts.parseConfigHostFromCompilerHost = parseConfigHostFromCompilerHost;
+    /**
+     * Returns the target config filename of a project reference
+     */
+    function resolveProjectReferencePath(host, ref) {
+        if (!host.fileExists(ref.path)) {
+            return ts.combinePaths(ref.path, "tsconfig.json");
+        }
+        return ref.path;
+    }
+    ts.resolveProjectReferencePath = resolveProjectReferencePath;
+    /* @internal */
+    /**
+     * Returns a DiagnosticMessage if we won't include a resolved module due to its extension.
+     * The DiagnosticMessage's parameters are the imported module name, and the filename it resolved to.
+     * This returns a diagnostic even if the module will be an untyped module.
+     */
+    function getResolutionDiagnostic(options, _a) {
+        var extension = _a.extension;
+        switch (extension) {
+            case ".ts" /* Ts */:
+            case ".d.ts" /* Dts */:
+            case ".json" /* Json */: // Since module is resolved to json file only when --resolveJsonModule, we dont need further check
+                // These are always allowed.
+                return undefined;
+            case ".tsx" /* Tsx */:
+                return needJsx();
+            case ".jsx" /* Jsx */:
+                return needJsx() || needAllowJs();
+            case ".js" /* Js */:
+                return needAllowJs();
+        }
+        function needJsx() {
+            return options.jsx ? undefined : ts.Diagnostics.Module_0_was_resolved_to_1_but_jsx_is_not_set;
+        }
+        function needAllowJs() {
+            return options.allowJs || !ts.getStrictOptionValue(options, "noImplicitAny") ? undefined : ts.Diagnostics.Could_not_find_a_declaration_file_for_module_0_1_implicitly_has_an_any_type;
+        }
+    }
+    ts.getResolutionDiagnostic = getResolutionDiagnostic;
+    function getModuleNames(_a) {
+        var imports = _a.imports, moduleAugmentations = _a.moduleAugmentations;
+        var res = imports.map(function (i) { return i.text; });
+        for (var _i = 0, moduleAugmentations_1 = moduleAugmentations; _i < moduleAugmentations_1.length; _i++) {
+            var aug = moduleAugmentations_1[_i];
+            if (aug.kind === 9 /* StringLiteral */) {
+                res.push(aug.text);
+            }
+            // Do nothing if it's an Identifier; we don't need to do module resolution for `declare global`.
+        }
+        return res;
+    }
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    function getFileEmitOutput(program, sourceFile, emitOnlyDtsFiles, cancellationToken, customTransformers) {
+        var outputFiles = [];
+        var emitResult = program.emit(sourceFile, writeFile, cancellationToken, emitOnlyDtsFiles, customTransformers);
+        return { outputFiles: outputFiles, emitSkipped: emitResult.emitSkipped };
+        function writeFile(fileName, text, writeByteOrderMark) {
+            outputFiles.push({ name: fileName, writeByteOrderMark: writeByteOrderMark, text: text });
+        }
+    }
+    ts.getFileEmitOutput = getFileEmitOutput;
+})(ts || (ts = {}));
+/*@internal*/
+(function (ts) {
+    var BuilderState;
+    (function (BuilderState) {
+        /**
+         * Gets the referenced files for a file from the program with values for the keys as referenced file's path to be true
+         */
+        function getReferencedFiles(program, sourceFile, getCanonicalFileName) {
+            var referencedFiles;
+            // We need to use a set here since the code can contain the same import twice,
+            // but that will only be one dependency.
+            // To avoid invernal conversion, the key of the referencedFiles map must be of type Path
+            if (sourceFile.imports && sourceFile.imports.length > 0) {
+                var checker = program.getTypeChecker();
+                for (var _i = 0, _a = sourceFile.imports; _i < _a.length; _i++) {
+                    var importName = _a[_i];
+                    var symbol = checker.getSymbolAtLocation(importName);
+                    if (symbol && symbol.declarations && symbol.declarations[0]) {
+                        var declarationSourceFile = ts.getSourceFileOfNode(symbol.declarations[0]);
+                        if (declarationSourceFile) {
+                            addReferencedFile(declarationSourceFile.path);
+                        }
+                    }
+                }
+            }
+            var sourceFileDirectory = ts.getDirectoryPath(sourceFile.path);
+            // Handle triple slash references
+            if (sourceFile.referencedFiles && sourceFile.referencedFiles.length > 0) {
+                for (var _b = 0, _c = sourceFile.referencedFiles; _b < _c.length; _b++) {
+                    var referencedFile = _c[_b];
+                    var referencedPath = ts.toPath(referencedFile.fileName, sourceFileDirectory, getCanonicalFileName);
+                    addReferencedFile(referencedPath);
+                }
+            }
+            // Handle type reference directives
+            if (sourceFile.resolvedTypeReferenceDirectiveNames) {
+                sourceFile.resolvedTypeReferenceDirectiveNames.forEach(function (resolvedTypeReferenceDirective) {
+                    if (!resolvedTypeReferenceDirective) {
+                        return;
+                    }
+                    var fileName = resolvedTypeReferenceDirective.resolvedFileName; // TODO: GH#18217
+                    var typeFilePath = ts.toPath(fileName, sourceFileDirectory, getCanonicalFileName);
+                    addReferencedFile(typeFilePath);
+                });
+            }
+            return referencedFiles;
+            function addReferencedFile(referencedPath) {
+                if (!referencedFiles) {
+                    referencedFiles = ts.createMap();
+                }
+                referencedFiles.set(referencedPath, true);
+            }
+        }
+        /**
+         * Returns true if oldState is reusable, that is the emitKind = module/non module has not changed
+         */
+        function canReuseOldState(newReferencedMap, oldState) {
+            return oldState && !oldState.referencedMap === !newReferencedMap;
+        }
+        BuilderState.canReuseOldState = canReuseOldState;
+        /**
+         * Creates the state of file references and signature for the new program from oldState if it is safe
+         */
+        function create(newProgram, getCanonicalFileName, oldState) {
+            var fileInfos = ts.createMap();
+            var referencedMap = newProgram.getCompilerOptions().module !== ts.ModuleKind.None ? ts.createMap() : undefined;
+            var hasCalledUpdateShapeSignature = ts.createMap();
+            var useOldState = canReuseOldState(referencedMap, oldState);
+            // Create the reference map, and set the file infos
+            for (var _i = 0, _a = newProgram.getSourceFiles(); _i < _a.length; _i++) {
+                var sourceFile = _a[_i];
+                var version_1 = sourceFile.version;
+                var oldInfo = useOldState ? oldState.fileInfos.get(sourceFile.path) : undefined;
+                if (referencedMap) {
+                    var newReferences = getReferencedFiles(newProgram, sourceFile, getCanonicalFileName);
+                    if (newReferences) {
+                        referencedMap.set(sourceFile.path, newReferences);
+                    }
+                }
+                fileInfos.set(sourceFile.path, { version: version_1, signature: oldInfo && oldInfo.signature });
+            }
+            return {
+                fileInfos: fileInfos,
+                referencedMap: referencedMap,
+                hasCalledUpdateShapeSignature: hasCalledUpdateShapeSignature,
+                allFilesExcludingDefaultLibraryFile: undefined,
+                allFileNames: undefined
+            };
+        }
+        BuilderState.create = create;
+        /**
+         * Gets the files affected by the path from the program
+         */
+        function getFilesAffectedBy(state, programOfThisState, path, cancellationToken, computeHash, cacheToUpdateSignature) {
+            // Since the operation could be cancelled, the signatures are always stored in the cache
+            // They will be commited once it is safe to use them
+            // eg when calling this api from tsserver, if there is no cancellation of the operation
+            // In the other cases the affected files signatures are commited only after the iteration through the result is complete
+            var signatureCache = cacheToUpdateSignature || ts.createMap();
+            var sourceFile = programOfThisState.getSourceFileByPath(path);
+            if (!sourceFile) {
+                return ts.emptyArray;
+            }
+            if (!updateShapeSignature(state, programOfThisState, sourceFile, signatureCache, cancellationToken, computeHash)) {
+                return [sourceFile];
+            }
+            var result = (state.referencedMap ? getFilesAffectedByUpdatedShapeWhenModuleEmit : getFilesAffectedByUpdatedShapeWhenNonModuleEmit)(state, programOfThisState, sourceFile, signatureCache, cancellationToken, computeHash);
+            if (!cacheToUpdateSignature) {
+                // Commit all the signatures in the signature cache
+                updateSignaturesFromCache(state, signatureCache);
+            }
+            return result;
+        }
+        BuilderState.getFilesAffectedBy = getFilesAffectedBy;
+        /**
+         * Updates the signatures from the cache into state's fileinfo signatures
+         * This should be called whenever it is safe to commit the state of the builder
+         */
+        function updateSignaturesFromCache(state, signatureCache) {
+            signatureCache.forEach(function (signature, path) {
+                state.fileInfos.get(path).signature = signature;
+                state.hasCalledUpdateShapeSignature.set(path, true);
+            });
+        }
+        BuilderState.updateSignaturesFromCache = updateSignaturesFromCache;
+        /**
+         * Returns if the shape of the signature has changed since last emit
+         */
+        function updateShapeSignature(state, programOfThisState, sourceFile, cacheToUpdateSignature, cancellationToken, computeHash) {
+            ts.Debug.assert(!!sourceFile);
+            // If we have cached the result for this file, that means hence forth we should assume file shape is uptodate
+            if (state.hasCalledUpdateShapeSignature.has(sourceFile.path) || cacheToUpdateSignature.has(sourceFile.path)) {
+                return false;
+            }
+            var info = state.fileInfos.get(sourceFile.path);
+            if (!info)
+                return ts.Debug.fail();
+            var prevSignature = info.signature;
+            var latestSignature;
+            if (sourceFile.isDeclarationFile) {
+                latestSignature = sourceFile.version;
+            }
+            else {
+                var emitOutput = ts.getFileEmitOutput(programOfThisState, sourceFile, /*emitOnlyDtsFiles*/ true, cancellationToken);
+                if (emitOutput.outputFiles && emitOutput.outputFiles.length > 0) {
+                    latestSignature = computeHash(emitOutput.outputFiles[0].text);
+                }
+                else {
+                    latestSignature = prevSignature; // TODO: GH#18217
+                }
+            }
+            cacheToUpdateSignature.set(sourceFile.path, latestSignature);
+            return !prevSignature || latestSignature !== prevSignature;
+        }
+        /**
+         * Get all the dependencies of the sourceFile
+         */
+        function getAllDependencies(state, programOfThisState, sourceFile) {
+            var _a;
+            var compilerOptions = programOfThisState.getCompilerOptions();
+            // With --out or --outFile all outputs go into single file, all files depend on each other
+            if (compilerOptions.outFile || compilerOptions.out) {
+                return getAllFileNames(state, programOfThisState);
+            }
+            // If this is non module emit, or its a global file, it depends on all the source files
+            if (!state.referencedMap || (!ts.isExternalModule(sourceFile) && !containsOnlyAmbientModules(sourceFile))) {
+                return getAllFileNames(state, programOfThisState);
+            }
+            // Get the references, traversing deep from the referenceMap
+            var seenMap = ts.createMap();
+            var queue = [sourceFile.path];
+            while (queue.length) {
+                var path = queue.pop();
+                if (!seenMap.has(path)) {
+                    seenMap.set(path, true);
+                    var references = state.referencedMap.get(path);
+                    if (references) {
+                        var iterator = references.keys();
+                        for (var _b = iterator.next(), value = _b.value, done = _b.done; !done; _a = iterator.next(), value = _a.value, done = _a.done, _a) {
+                            queue.push(value);
+                        }
+                    }
+                }
+            }
+            return ts.arrayFrom(ts.mapDefinedIterator(seenMap.keys(), function (path) {
+                var file = programOfThisState.getSourceFileByPath(path);
+                return file ? file.fileName : path;
+            }));
+        }
+        BuilderState.getAllDependencies = getAllDependencies;
+        /**
+         * Gets the names of all files from the program
+         */
+        function getAllFileNames(state, programOfThisState) {
+            if (!state.allFileNames) {
+                var sourceFiles = programOfThisState.getSourceFiles();
+                state.allFileNames = sourceFiles === ts.emptyArray ? ts.emptyArray : sourceFiles.map(function (file) { return file.fileName; });
+            }
+            return state.allFileNames;
+        }
+        /**
+         * Gets the files referenced by the the file path
+         */
+        function getReferencedByPaths(state, referencedFilePath) {
+            return ts.arrayFrom(ts.mapDefinedIterator(state.referencedMap.entries(), function (_a) {
+                var filePath = _a[0], referencesInFile = _a[1];
+                return referencesInFile.has(referencedFilePath) ? filePath : undefined;
+            }));
+        }
+        /**
+         * For script files that contains only ambient external modules, although they are not actually external module files,
+         * they can only be consumed via importing elements from them. Regular script files cannot consume them. Therefore,
+         * there are no point to rebuild all script files if these special files have changed. However, if any statement
+         * in the file is not ambient external module, we treat it as a regular script file.
+         */
+        function containsOnlyAmbientModules(sourceFile) {
+            for (var _i = 0, _a = sourceFile.statements; _i < _a.length; _i++) {
+                var statement = _a[_i];
+                if (!ts.isModuleWithStringLiteralName(statement)) {
+                    return false;
+                }
+            }
+            return true;
+        }
+        /**
+         * Gets all files of the program excluding the default library file
+         */
+        function getAllFilesExcludingDefaultLibraryFile(state, programOfThisState, firstSourceFile) {
+            // Use cached result
+            if (state.allFilesExcludingDefaultLibraryFile) {
+                return state.allFilesExcludingDefaultLibraryFile;
+            }
+            var result;
+            addSourceFile(firstSourceFile);
+            for (var _i = 0, _a = programOfThisState.getSourceFiles(); _i < _a.length; _i++) {
+                var sourceFile = _a[_i];
+                if (sourceFile !== firstSourceFile) {
+                    addSourceFile(sourceFile);
+                }
+            }
+            state.allFilesExcludingDefaultLibraryFile = result || ts.emptyArray;
+            return state.allFilesExcludingDefaultLibraryFile;
+            function addSourceFile(sourceFile) {
+                if (!programOfThisState.isSourceFileDefaultLibrary(sourceFile)) {
+                    (result || (result = [])).push(sourceFile);
+                }
+            }
+        }
+        /**
+         * When program emits non modular code, gets the files affected by the sourceFile whose shape has changed
+         */
+        function getFilesAffectedByUpdatedShapeWhenNonModuleEmit(state, programOfThisState, sourceFileWithUpdatedShape) {
+            var compilerOptions = programOfThisState.getCompilerOptions();
+            // If `--out` or `--outFile` is specified, any new emit will result in re-emitting the entire project,
+            // so returning the file itself is good enough.
+            if (compilerOptions && (compilerOptions.out || compilerOptions.outFile)) {
+                return [sourceFileWithUpdatedShape];
+            }
+            return getAllFilesExcludingDefaultLibraryFile(state, programOfThisState, sourceFileWithUpdatedShape);
+        }
+        /**
+         * When program emits modular code, gets the files affected by the sourceFile whose shape has changed
+         */
+        function getFilesAffectedByUpdatedShapeWhenModuleEmit(state, programOfThisState, sourceFileWithUpdatedShape, cacheToUpdateSignature, cancellationToken, computeHash) {
+            if (!ts.isExternalModule(sourceFileWithUpdatedShape) && !containsOnlyAmbientModules(sourceFileWithUpdatedShape)) {
+                return getAllFilesExcludingDefaultLibraryFile(state, programOfThisState, sourceFileWithUpdatedShape);
+            }
+            var compilerOptions = programOfThisState.getCompilerOptions();
+            if (compilerOptions && (compilerOptions.isolatedModules || compilerOptions.out || compilerOptions.outFile)) {
+                return [sourceFileWithUpdatedShape];
+            }
+            // Now we need to if each file in the referencedBy list has a shape change as well.
+            // Because if so, its own referencedBy files need to be saved as well to make the
+            // emitting result consistent with files on disk.
+            var seenFileNamesMap = ts.createMap();
+            // Start with the paths this file was referenced by
+            seenFileNamesMap.set(sourceFileWithUpdatedShape.path, sourceFileWithUpdatedShape);
+            var queue = getReferencedByPaths(state, sourceFileWithUpdatedShape.path);
+            while (queue.length > 0) {
+                var currentPath = queue.pop();
+                if (!seenFileNamesMap.has(currentPath)) {
+                    var currentSourceFile = programOfThisState.getSourceFileByPath(currentPath);
+                    seenFileNamesMap.set(currentPath, currentSourceFile);
+                    if (currentSourceFile && updateShapeSignature(state, programOfThisState, currentSourceFile, cacheToUpdateSignature, cancellationToken, computeHash)) { // TODO: GH#18217
+                        queue.push.apply(// TODO: GH#18217
+                        queue, getReferencedByPaths(state, currentPath));
+                    }
+                }
+            }
+            // Return array of values that needs emit
+            // Return array of values that needs emit
+            return ts.arrayFrom(ts.mapDefinedIterator(seenFileNamesMap.values(), function (value) { return value; }));
+        }
+    })(BuilderState = ts.BuilderState || (ts.BuilderState = {}));
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    function hasSameKeys(map1, map2) {
+        // Has same size and every key is present in both maps
+        return map1 === map2 || map1 !== undefined && map2 !== undefined && map1.size === map2.size && !ts.forEachKey(map1, function (key) { return !map2.has(key); });
+    }
+    /**
+     * Create the state so that we can iterate on changedFiles/affected files
+     */
+    function createBuilderProgramState(newProgram, getCanonicalFileName, oldState) {
+        var state = ts.BuilderState.create(newProgram, getCanonicalFileName, oldState);
+        state.program = newProgram;
+        var compilerOptions = newProgram.getCompilerOptions();
+        if (!compilerOptions.outFile && !compilerOptions.out) {
+            state.semanticDiagnosticsPerFile = ts.createMap();
+        }
+        state.changedFilesSet = ts.createMap();
+        var useOldState = ts.BuilderState.canReuseOldState(state.referencedMap, oldState);
+        var canCopySemanticDiagnostics = useOldState && oldState.semanticDiagnosticsPerFile && !!state.semanticDiagnosticsPerFile;
+        if (useOldState) {
+            // Verify the sanity of old state
+            if (!oldState.currentChangedFilePath) {
+                ts.Debug.assert(!oldState.affectedFiles && (!oldState.currentAffectedFilesSignatures || !oldState.currentAffectedFilesSignatures.size), "Cannot reuse if only few affected files of currentChangedFile were iterated");
+            }
+            if (canCopySemanticDiagnostics) {
+                ts.Debug.assert(!ts.forEachKey(oldState.changedFilesSet, function (path) { return oldState.semanticDiagnosticsPerFile.has(path); }), "Semantic diagnostics shouldnt be available for changed files");
+            }
+            // Copy old state's changed files set
+            ts.copyEntries(oldState.changedFilesSet, state.changedFilesSet);
+        }
+        // Update changed files and copy semantic diagnostics if we can
+        var referencedMap = state.referencedMap;
+        var oldReferencedMap = useOldState ? oldState.referencedMap : undefined;
+        state.fileInfos.forEach(function (info, sourceFilePath) {
+            var oldInfo;
+            var newReferences;
+            // if not using old state, every file is changed
+            if (!useOldState ||
+                // File wasnt present in old state
+                !(oldInfo = oldState.fileInfos.get(sourceFilePath)) ||
+                // versions dont match
+                oldInfo.version !== info.version ||
+                // Referenced files changed
+                !hasSameKeys(newReferences = referencedMap && referencedMap.get(sourceFilePath), oldReferencedMap && oldReferencedMap.get(sourceFilePath)) ||
+                // Referenced file was deleted in the new program
+                newReferences && ts.forEachKey(newReferences, function (path) { return !state.fileInfos.has(path) && oldState.fileInfos.has(path); })) {
+                // Register file as changed file and do not copy semantic diagnostics, since all changed files need to be re-evaluated
+                state.changedFilesSet.set(sourceFilePath, true);
+            }
+            else if (canCopySemanticDiagnostics) {
+                // Unchanged file copy diagnostics
+                var diagnostics = oldState.semanticDiagnosticsPerFile.get(sourceFilePath);
+                if (diagnostics) {
+                    state.semanticDiagnosticsPerFile.set(sourceFilePath, diagnostics);
+                }
+            }
+        });
+        return state;
+    }
+    /**
+     * Verifies that source file is ok to be used in calls that arent handled by next
+     */
+    function assertSourceFileOkWithoutNextAffectedCall(state, sourceFile) {
+        ts.Debug.assert(!sourceFile || !state.affectedFiles || state.affectedFiles[state.affectedFilesIndex - 1] !== sourceFile || !state.semanticDiagnosticsPerFile.has(sourceFile.path));
+    }
+    /**
+     * This function returns the next affected file to be processed.
+     * Note that until doneAffected is called it would keep reporting same result
+     * This is to allow the callers to be able to actually remove affected file only when the operation is complete
+     * eg. if during diagnostics check cancellation token ends up cancelling the request, the affected file should be retained
+     */
+    function getNextAffectedFile(state, cancellationToken, computeHash) {
+        while (true) {
+            var affectedFiles = state.affectedFiles;
+            if (affectedFiles) {
+                var seenAffectedFiles = state.seenAffectedFiles, semanticDiagnosticsPerFile = state.semanticDiagnosticsPerFile;
+                var affectedFilesIndex = state.affectedFilesIndex; // TODO: GH#18217
+                while (affectedFilesIndex < affectedFiles.length) {
+                    var affectedFile = affectedFiles[affectedFilesIndex];
+                    if (!seenAffectedFiles.has(affectedFile.path)) {
+                        // Set the next affected file as seen and remove the cached semantic diagnostics
+                        state.affectedFilesIndex = affectedFilesIndex;
+                        semanticDiagnosticsPerFile.delete(affectedFile.path);
+                        return affectedFile;
+                    }
+                    seenAffectedFiles.set(affectedFile.path, true);
+                    affectedFilesIndex++;
+                }
+                // Remove the changed file from the change set
+                state.changedFilesSet.delete(state.currentChangedFilePath);
+                state.currentChangedFilePath = undefined;
+                // Commit the changes in file signature
+                ts.BuilderState.updateSignaturesFromCache(state, state.currentAffectedFilesSignatures);
+                state.currentAffectedFilesSignatures.clear();
+                state.affectedFiles = undefined;
+            }
+            // Get next changed file
+            var nextKey = state.changedFilesSet.keys().next();
+            if (nextKey.done) {
+                // Done
+                return undefined;
+            }
+            // With --out or --outFile all outputs go into single file
+            // so operations are performed directly on program, return program
+            var compilerOptions = state.program.getCompilerOptions();
+            if (compilerOptions.outFile || compilerOptions.out) {
+                ts.Debug.assert(!state.semanticDiagnosticsPerFile);
+                return state.program;
+            }
+            // Get next batch of affected files
+            state.currentAffectedFilesSignatures = state.currentAffectedFilesSignatures || ts.createMap();
+            state.affectedFiles = ts.BuilderState.getFilesAffectedBy(state, state.program, nextKey.value, cancellationToken, computeHash, state.currentAffectedFilesSignatures);
+            state.currentChangedFilePath = nextKey.value;
+            state.semanticDiagnosticsPerFile.delete(nextKey.value);
+            state.affectedFilesIndex = 0;
+            state.seenAffectedFiles = state.seenAffectedFiles || ts.createMap();
+        }
+    }
+    /**
+     * This is called after completing operation on the next affected file.
+     * The operations here are postponed to ensure that cancellation during the iteration is handled correctly
+     */
+    function doneWithAffectedFile(state, affected) {
+        if (affected === state.program) {
+            state.changedFilesSet.clear();
+        }
+        else {
+            state.seenAffectedFiles.set(affected.path, true);
+            state.affectedFilesIndex++;
+        }
+    }
+    /**
+     * Returns the result with affected file
+     */
+    function toAffectedFileResult(state, result, affected) {
+        doneWithAffectedFile(state, affected);
+        return { result: result, affected: affected };
+    }
+    /**
+     * Gets the semantic diagnostics either from cache if present, or otherwise from program and caches it
+     * Note that it is assumed that the when asked about semantic diagnostics, the file has been taken out of affected files/changed file set
+     */
+    function getSemanticDiagnosticsOfFile(state, sourceFile, cancellationToken) {
+        var path = sourceFile.path;
+        var cachedDiagnostics = state.semanticDiagnosticsPerFile.get(path);
+        // Report the semantic diagnostics from the cache if we already have those diagnostics present
+        if (cachedDiagnostics) {
+            return cachedDiagnostics;
+        }
+        // Diagnostics werent cached, get them from program, and cache the result
+        var diagnostics = state.program.getSemanticDiagnostics(sourceFile, cancellationToken);
+        state.semanticDiagnosticsPerFile.set(path, diagnostics);
+        return diagnostics;
+    }
+    var BuilderProgramKind;
+    (function (BuilderProgramKind) {
+        BuilderProgramKind[BuilderProgramKind["SemanticDiagnosticsBuilderProgram"] = 0] = "SemanticDiagnosticsBuilderProgram";
+        BuilderProgramKind[BuilderProgramKind["EmitAndSemanticDiagnosticsBuilderProgram"] = 1] = "EmitAndSemanticDiagnosticsBuilderProgram";
+    })(BuilderProgramKind = ts.BuilderProgramKind || (ts.BuilderProgramKind = {}));
+    function getBuilderCreationParameters(newProgramOrRootNames, hostOrOptions, oldProgramOrHost, configFileParsingDiagnosticsOrOldProgram, configFileParsingDiagnostics) {
+        var host;
+        var newProgram;
+        var oldProgram;
+        if (newProgramOrRootNames === undefined) {
+            ts.Debug.assert(hostOrOptions === undefined);
+            host = oldProgramOrHost;
+            oldProgram = configFileParsingDiagnosticsOrOldProgram;
+            ts.Debug.assert(!!oldProgram);
+            newProgram = oldProgram.getProgram();
+        }
+        else if (ts.isArray(newProgramOrRootNames)) {
+            oldProgram = configFileParsingDiagnosticsOrOldProgram;
+            newProgram = ts.createProgram(newProgramOrRootNames, hostOrOptions, oldProgramOrHost, oldProgram && oldProgram.getProgram(), configFileParsingDiagnostics);
+            host = oldProgramOrHost;
+        }
+        else {
+            newProgram = newProgramOrRootNames;
+            host = hostOrOptions;
+            oldProgram = oldProgramOrHost;
+            configFileParsingDiagnostics = configFileParsingDiagnosticsOrOldProgram;
+        }
+        return { host: host, newProgram: newProgram, oldProgram: oldProgram, configFileParsingDiagnostics: configFileParsingDiagnostics || ts.emptyArray };
+    }
+    ts.getBuilderCreationParameters = getBuilderCreationParameters;
+    function createBuilderProgram(kind, _a) {
+        var newProgram = _a.newProgram, host = _a.host, oldProgram = _a.oldProgram, configFileParsingDiagnostics = _a.configFileParsingDiagnostics;
+        // Return same program if underlying program doesnt change
+        var oldState = oldProgram && oldProgram.getState();
+        if (oldState && newProgram === oldState.program && configFileParsingDiagnostics === newProgram.getConfigFileParsingDiagnostics()) {
+            newProgram = undefined; // TODO: GH#18217
+            oldState = undefined;
+            return oldProgram;
+        }
+        /**
+         * Create the canonical file name for identity
+         */
+        var getCanonicalFileName = ts.createGetCanonicalFileName(host.useCaseSensitiveFileNames());
+        /**
+         * Computing hash to for signature verification
+         */
+        var computeHash = host.createHash || ts.identity;
+        var state = createBuilderProgramState(newProgram, getCanonicalFileName, oldState);
+        // To ensure that we arent storing any references to old program or new program without state
+        newProgram = undefined; // TODO: GH#18217
+        oldProgram = undefined;
+        oldState = undefined;
+        var result = {
+            getState: function () { return state; },
+            getProgram: function () { return state.program; },
+            getCompilerOptions: function () { return state.program.getCompilerOptions(); },
+            getSourceFile: function (fileName) { return state.program.getSourceFile(fileName); },
+            getSourceFiles: function () { return state.program.getSourceFiles(); },
+            getOptionsDiagnostics: function (cancellationToken) { return state.program.getOptionsDiagnostics(cancellationToken); },
+            getGlobalDiagnostics: function (cancellationToken) { return state.program.getGlobalDiagnostics(cancellationToken); },
+            getConfigFileParsingDiagnostics: function () { return configFileParsingDiagnostics || state.program.getConfigFileParsingDiagnostics(); },
+            getSyntacticDiagnostics: function (sourceFile, cancellationToken) { return state.program.getSyntacticDiagnostics(sourceFile, cancellationToken); },
+            getSemanticDiagnostics: getSemanticDiagnostics,
+            emit: emit,
+            getAllDependencies: function (sourceFile) { return ts.BuilderState.getAllDependencies(state, state.program, sourceFile); },
+            getCurrentDirectory: function () { return state.program.getCurrentDirectory(); }
+        };
+        if (kind === BuilderProgramKind.SemanticDiagnosticsBuilderProgram) {
+            result.getSemanticDiagnosticsOfNextAffectedFile = getSemanticDiagnosticsOfNextAffectedFile;
+        }
+        else if (kind === BuilderProgramKind.EmitAndSemanticDiagnosticsBuilderProgram) {
+            result.emitNextAffectedFile = emitNextAffectedFile;
+        }
+        else {
+            ts.notImplemented();
+        }
+        return result;
+        /**
+         * Emits the next affected file's emit result (EmitResult and sourceFiles emitted) or returns undefined if iteration is complete
+         * The first of writeFile if provided, writeFile of BuilderProgramHost if provided, writeFile of compiler host
+         * in that order would be used to write the files
+         */
+        function emitNextAffectedFile(writeFile, cancellationToken, emitOnlyDtsFiles, customTransformers) {
+            var affected = getNextAffectedFile(state, cancellationToken, computeHash);
+            if (!affected) {
+                // Done
+                return undefined;
+            }
+            return toAffectedFileResult(state, 
+            // When whole program is affected, do emit only once (eg when --out or --outFile is specified)
+            // Otherwise just affected file
+            state.program.emit(affected === state.program ? undefined : affected, writeFile || host.writeFile, cancellationToken, emitOnlyDtsFiles, customTransformers), affected);
+        }
+        /**
+         * Emits the JavaScript and declaration files.
+         * When targetSource file is specified, emits the files corresponding to that source file,
+         * otherwise for the whole program.
+         * In case of EmitAndSemanticDiagnosticsBuilderProgram, when targetSourceFile is specified,
+         * it is assumed that that file is handled from affected file list. If targetSourceFile is not specified,
+         * it will only emit all the affected files instead of whole program
+         *
+         * The first of writeFile if provided, writeFile of BuilderProgramHost if provided, writeFile of compiler host
+         * in that order would be used to write the files
+         */
+        function emit(targetSourceFile, writeFile, cancellationToken, emitOnlyDtsFiles, customTransformers) {
+            if (kind === BuilderProgramKind.EmitAndSemanticDiagnosticsBuilderProgram) {
+                assertSourceFileOkWithoutNextAffectedCall(state, targetSourceFile);
+                if (!targetSourceFile) {
+                    // Emit and report any errors we ran into.
+                    var sourceMaps = [];
+                    var emitSkipped = false;
+                    var diagnostics = void 0;
+                    var emittedFiles = [];
+                    var affectedEmitResult = void 0;
+                    while (affectedEmitResult = emitNextAffectedFile(writeFile, cancellationToken, emitOnlyDtsFiles, customTransformers)) {
+                        emitSkipped = emitSkipped || affectedEmitResult.result.emitSkipped;
+                        diagnostics = ts.addRange(diagnostics, affectedEmitResult.result.diagnostics);
+                        emittedFiles = ts.addRange(emittedFiles, affectedEmitResult.result.emittedFiles);
+                        sourceMaps = ts.addRange(sourceMaps, affectedEmitResult.result.sourceMaps);
+                    }
+                    return {
+                        emitSkipped: emitSkipped,
+                        diagnostics: diagnostics || ts.emptyArray,
+                        emittedFiles: emittedFiles,
+                        sourceMaps: sourceMaps
+                    };
+                }
+            }
+            return state.program.emit(targetSourceFile, writeFile || host.writeFile, cancellationToken, emitOnlyDtsFiles, customTransformers);
+        }
+        /**
+         * Return the semantic diagnostics for the next affected file or undefined if iteration is complete
+         * If provided ignoreSourceFile would be called before getting the diagnostics and would ignore the sourceFile if the returned value was true
+         */
+        function getSemanticDiagnosticsOfNextAffectedFile(cancellationToken, ignoreSourceFile) {
+            while (true) {
+                var affected = getNextAffectedFile(state, cancellationToken, computeHash);
+                if (!affected) {
+                    // Done
+                    return undefined;
+                }
+                else if (affected === state.program) {
+                    // When whole program is affected, get all semantic diagnostics (eg when --out or --outFile is specified)
+                    return toAffectedFileResult(state, state.program.getSemanticDiagnostics(/*targetSourceFile*/ undefined, cancellationToken), affected);
+                }
+                // Get diagnostics for the affected file if its not ignored
+                if (ignoreSourceFile && ignoreSourceFile(affected)) {
+                    // Get next affected file
+                    doneWithAffectedFile(state, affected);
+                    continue;
+                }
+                return toAffectedFileResult(state, getSemanticDiagnosticsOfFile(state, affected, cancellationToken), affected);
+            }
+        }
+        /**
+         * Gets the semantic diagnostics from the program corresponding to this state of file (if provided) or whole program
+         * The semantic diagnostics are cached and managed here
+         * Note that it is assumed that when asked about semantic diagnostics through this API,
+         * the file has been taken out of affected files so it is safe to use cache or get from program and cache the diagnostics
+         * In case of SemanticDiagnosticsBuilderProgram if the source file is not provided,
+         * it will iterate through all the affected files, to ensure that cache stays valid and yet provide a way to get all semantic diagnostics
+         */
+        function getSemanticDiagnostics(sourceFile, cancellationToken) {
+            assertSourceFileOkWithoutNextAffectedCall(state, sourceFile);
+            var compilerOptions = state.program.getCompilerOptions();
+            if (compilerOptions.outFile || compilerOptions.out) {
+                ts.Debug.assert(!state.semanticDiagnosticsPerFile);
+                // We dont need to cache the diagnostics just return them from program
+                return state.program.getSemanticDiagnostics(sourceFile, cancellationToken);
+            }
+            if (sourceFile) {
+                return getSemanticDiagnosticsOfFile(state, sourceFile, cancellationToken);
+            }
+            if (kind === BuilderProgramKind.SemanticDiagnosticsBuilderProgram) {
+                // When semantic builder asks for diagnostics of the whole program,
+                // ensure that all the affected files are handled
+                var affected = void 0;
+                while (affected = getNextAffectedFile(state, cancellationToken, computeHash)) {
+                    doneWithAffectedFile(state, affected);
+                }
+            }
+            var diagnostics;
+            for (var _i = 0, _a = state.program.getSourceFiles(); _i < _a.length; _i++) {
+                var sourceFile_2 = _a[_i];
+                diagnostics = ts.addRange(diagnostics, getSemanticDiagnosticsOfFile(state, sourceFile_2, cancellationToken));
+            }
+            return diagnostics || ts.emptyArray;
+        }
+    }
+    ts.createBuilderProgram = createBuilderProgram;
+})(ts || (ts = {}));
+(function (ts) {
+    function createSemanticDiagnosticsBuilderProgram(newProgramOrRootNames, hostOrOptions, oldProgramOrHost, configFileParsingDiagnosticsOrOldProgram, configFileParsingDiagnostics) {
+        return ts.createBuilderProgram(ts.BuilderProgramKind.SemanticDiagnosticsBuilderProgram, ts.getBuilderCreationParameters(newProgramOrRootNames, hostOrOptions, oldProgramOrHost, configFileParsingDiagnosticsOrOldProgram, configFileParsingDiagnostics));
+    }
+    ts.createSemanticDiagnosticsBuilderProgram = createSemanticDiagnosticsBuilderProgram;
+    function createEmitAndSemanticDiagnosticsBuilderProgram(newProgramOrRootNames, hostOrOptions, oldProgramOrHost, configFileParsingDiagnosticsOrOldProgram, configFileParsingDiagnostics) {
+        return ts.createBuilderProgram(ts.BuilderProgramKind.EmitAndSemanticDiagnosticsBuilderProgram, ts.getBuilderCreationParameters(newProgramOrRootNames, hostOrOptions, oldProgramOrHost, configFileParsingDiagnosticsOrOldProgram, configFileParsingDiagnostics));
+    }
+    ts.createEmitAndSemanticDiagnosticsBuilderProgram = createEmitAndSemanticDiagnosticsBuilderProgram;
+    function createAbstractBuilder(newProgramOrRootNames, hostOrOptions, oldProgramOrHost, configFileParsingDiagnosticsOrOldProgram, configFileParsingDiagnostics) {
+        var program = ts.getBuilderCreationParameters(newProgramOrRootNames, hostOrOptions, oldProgramOrHost, configFileParsingDiagnosticsOrOldProgram, configFileParsingDiagnostics).newProgram;
+        return {
+            // Only return program, all other methods are not implemented
+            getProgram: function () { return program; },
+            getState: ts.notImplemented,
+            getCompilerOptions: ts.notImplemented,
+            getSourceFile: ts.notImplemented,
+            getSourceFiles: ts.notImplemented,
+            getOptionsDiagnostics: ts.notImplemented,
+            getGlobalDiagnostics: ts.notImplemented,
+            getConfigFileParsingDiagnostics: ts.notImplemented,
+            getSyntacticDiagnostics: ts.notImplemented,
+            getSemanticDiagnostics: ts.notImplemented,
+            emit: ts.notImplemented,
+            getAllDependencies: ts.notImplemented,
+            getCurrentDirectory: ts.notImplemented
+        };
+    }
+    ts.createAbstractBuilder = createAbstractBuilder;
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    ts.maxNumberOfFilesToIterateForInvalidation = 256;
+    function createResolutionCache(resolutionHost, rootDirForResolution, logChangesWhenResolvingModule) {
+        var filesWithChangedSetOfUnresolvedImports;
+        var filesWithInvalidatedResolutions;
+        var filesWithInvalidatedNonRelativeUnresolvedImports;
+        var allFilesHaveInvalidatedResolution = false;
+        var getCurrentDirectory = ts.memoize(function () { return resolutionHost.getCurrentDirectory(); }); // TODO: GH#18217
+        var cachedDirectoryStructureHost = resolutionHost.getCachedDirectoryStructureHost();
+        // The resolvedModuleNames and resolvedTypeReferenceDirectives are the cache of resolutions per file.
+        // The key in the map is source file's path.
+        // The values are Map of resolutions with key being name lookedup.
+        var resolvedModuleNames = ts.createMap();
+        var perDirectoryResolvedModuleNames = ts.createMap();
+        var nonRelaticeModuleNameCache = ts.createMap();
+        var moduleResolutionCache = ts.createModuleResolutionCacheWithMaps(perDirectoryResolvedModuleNames, nonRelaticeModuleNameCache, getCurrentDirectory(), resolutionHost.getCanonicalFileName);
+        var resolvedTypeReferenceDirectives = ts.createMap();
+        var perDirectoryResolvedTypeReferenceDirectives = ts.createMap();
+        /**
+         * These are the extensions that failed lookup files will have by default,
+         * any other extension of failed lookup will be store that path in custom failed lookup path
+         * This helps in not having to comb through all resolutions when files are added/removed
+         * Note that .d.ts file also has .d.ts extension hence will be part of default extensions
+         */
+        var failedLookupDefaultExtensions = [".ts" /* Ts */, ".tsx" /* Tsx */, ".js" /* Js */, ".jsx" /* Jsx */, ".json" /* Json */];
+        var customFailedLookupPaths = ts.createMap();
+        var directoryWatchesOfFailedLookups = ts.createMap();
+        var rootDir = rootDirForResolution && ts.removeTrailingDirectorySeparator(ts.getNormalizedAbsolutePath(rootDirForResolution, getCurrentDirectory()));
+        var rootPath = (rootDir && resolutionHost.toPath(rootDir)); // TODO: GH#18217
+        // TypeRoot watches for the types that get added as part of getAutomaticTypeDirectiveNames
+        var typeRootsWatches = ts.createMap();
+        return {
+            startRecordingFilesWithChangedResolutions: startRecordingFilesWithChangedResolutions,
+            finishRecordingFilesWithChangedResolutions: finishRecordingFilesWithChangedResolutions,
+            // perDirectoryResolvedModuleNames and perDirectoryResolvedTypeReferenceDirectives could be non empty if there was exception during program update
+            // (between startCachingPerDirectoryResolution and finishCachingPerDirectoryResolution)
+            startCachingPerDirectoryResolution: clearPerDirectoryResolutions,
+            finishCachingPerDirectoryResolution: finishCachingPerDirectoryResolution,
+            resolveModuleNames: resolveModuleNames,
+            getResolvedModuleWithFailedLookupLocationsFromCache: getResolvedModuleWithFailedLookupLocationsFromCache,
+            resolveTypeReferenceDirectives: resolveTypeReferenceDirectives,
+            removeResolutionsOfFile: removeResolutionsOfFile,
+            invalidateResolutionOfFile: invalidateResolutionOfFile,
+            setFilesWithInvalidatedNonRelativeUnresolvedImports: setFilesWithInvalidatedNonRelativeUnresolvedImports,
+            createHasInvalidatedResolution: createHasInvalidatedResolution,
+            updateTypeRootsWatch: updateTypeRootsWatch,
+            closeTypeRootsWatch: closeTypeRootsWatch,
+            clear: clear
+        };
+        function getResolvedModule(resolution) {
+            return resolution.resolvedModule;
+        }
+        function getResolvedTypeReferenceDirective(resolution) {
+            return resolution.resolvedTypeReferenceDirective;
+        }
+        function isInDirectoryPath(dir, file) {
+            if (dir === undefined || file.length <= dir.length) {
+                return false;
+            }
+            return ts.startsWith(file, dir) && file[dir.length] === ts.directorySeparator;
+        }
+        function clear() {
+            ts.clearMap(directoryWatchesOfFailedLookups, ts.closeFileWatcherOf);
+            customFailedLookupPaths.clear();
+            closeTypeRootsWatch();
+            resolvedModuleNames.clear();
+            resolvedTypeReferenceDirectives.clear();
+            allFilesHaveInvalidatedResolution = false;
+            // perDirectoryResolvedModuleNames and perDirectoryResolvedTypeReferenceDirectives could be non empty if there was exception during program update
+            // (between startCachingPerDirectoryResolution and finishCachingPerDirectoryResolution)
+            clearPerDirectoryResolutions();
+        }
+        function startRecordingFilesWithChangedResolutions() {
+            filesWithChangedSetOfUnresolvedImports = [];
+        }
+        function finishRecordingFilesWithChangedResolutions() {
+            var collected = filesWithChangedSetOfUnresolvedImports;
+            filesWithChangedSetOfUnresolvedImports = undefined;
+            return collected;
+        }
+        function isFileWithInvalidatedNonRelativeUnresolvedImports(path) {
+            if (!filesWithInvalidatedNonRelativeUnresolvedImports) {
+                return false;
+            }
+            // Invalidated if file has unresolved imports
+            var value = filesWithInvalidatedNonRelativeUnresolvedImports.get(path);
+            return !!value && !!value.length;
+        }
+        function createHasInvalidatedResolution(forceAllFilesAsInvalidated) {
+            if (allFilesHaveInvalidatedResolution || forceAllFilesAsInvalidated) {
+                // Any file asked would have invalidated resolution
+                filesWithInvalidatedResolutions = undefined;
+                return ts.returnTrue;
+            }
+            var collected = filesWithInvalidatedResolutions;
+            filesWithInvalidatedResolutions = undefined;
+            return function (path) { return (!!collected && collected.has(path)) ||
+                isFileWithInvalidatedNonRelativeUnresolvedImports(path); };
+        }
+        function clearPerDirectoryResolutions() {
+            perDirectoryResolvedModuleNames.clear();
+            nonRelaticeModuleNameCache.clear();
+            perDirectoryResolvedTypeReferenceDirectives.clear();
+        }
+        function finishCachingPerDirectoryResolution() {
+            allFilesHaveInvalidatedResolution = false;
+            filesWithInvalidatedNonRelativeUnresolvedImports = undefined;
+            directoryWatchesOfFailedLookups.forEach(function (watcher, path) {
+                if (watcher.refCount === 0) {
+                    directoryWatchesOfFailedLookups.delete(path);
+                    watcher.watcher.close();
+                }
+            });
+            clearPerDirectoryResolutions();
+        }
+        function resolveModuleName(moduleName, containingFile, compilerOptions, host) {
+            var primaryResult = ts.resolveModuleName(moduleName, containingFile, compilerOptions, host, moduleResolutionCache);
+            // return result immediately only if global cache support is not enabled or if it is .ts, .tsx or .d.ts
+            if (!resolutionHost.getGlobalCache) {
+                return primaryResult;
+            }
+            // otherwise try to load typings from @types
+            var globalCache = resolutionHost.getGlobalCache();
+            if (globalCache !== undefined && !ts.isExternalModuleNameRelative(moduleName) && !(primaryResult.resolvedModule && ts.extensionIsTypeScript(primaryResult.resolvedModule.extension))) {
+                // create different collection of failed lookup locations for second pass
+                // if it will fail and we've already found something during the first pass - we don't want to pollute its results
+                var _a = ts.loadModuleFromGlobalCache(moduleName, resolutionHost.projectName, compilerOptions, host, globalCache), resolvedModule = _a.resolvedModule, failedLookupLocations = _a.failedLookupLocations;
+                if (resolvedModule) {
+                    return { resolvedModule: resolvedModule, failedLookupLocations: ts.addRange(primaryResult.failedLookupLocations, failedLookupLocations) };
+                }
+            }
+            // Default return the result from the first pass
+            return primaryResult;
+        }
+        function resolveNamesWithLocalCache(names, containingFile, cache, perDirectoryCache, loader, getResolutionWithResolvedFileName, reusedNames, logChanges) {
+            var path = resolutionHost.toPath(containingFile);
+            var resolutionsInFile = cache.get(path) || cache.set(path, ts.createMap()).get(path);
+            var dirPath = ts.getDirectoryPath(path);
+            var perDirectoryResolution = perDirectoryCache.get(dirPath);
+            if (!perDirectoryResolution) {
+                perDirectoryResolution = ts.createMap();
+                perDirectoryCache.set(dirPath, perDirectoryResolution);
+            }
+            var resolvedModules = [];
+            var compilerOptions = resolutionHost.getCompilationSettings();
+            var hasInvalidatedNonRelativeUnresolvedImport = logChanges && isFileWithInvalidatedNonRelativeUnresolvedImports(path);
+            var seenNamesInFile = ts.createMap();
+            for (var _i = 0, names_2 = names; _i < names_2.length; _i++) {
+                var name = names_2[_i];
+                var resolution = resolutionsInFile.get(name);
+                // Resolution is valid if it is present and not invalidated
+                if (!seenNamesInFile.has(name) &&
+                    allFilesHaveInvalidatedResolution || !resolution || resolution.isInvalidated ||
+                    // If the name is unresolved import that was invalidated, recalculate
+                    (hasInvalidatedNonRelativeUnresolvedImport && !ts.isExternalModuleNameRelative(name) && !getResolutionWithResolvedFileName(resolution))) {
+                    var existingResolution = resolution;
+                    var resolutionInDirectory = perDirectoryResolution.get(name);
+                    if (resolutionInDirectory) {
+                        resolution = resolutionInDirectory;
+                    }
+                    else {
+                        resolution = loader(name, containingFile, compilerOptions, resolutionHost);
+                        perDirectoryResolution.set(name, resolution);
+                    }
+                    resolutionsInFile.set(name, resolution);
+                    watchFailedLookupLocationOfResolution(resolution);
+                    if (existingResolution) {
+                        stopWatchFailedLookupLocationOfResolution(existingResolution);
+                    }
+                    if (logChanges && filesWithChangedSetOfUnresolvedImports && !resolutionIsEqualTo(existingResolution, resolution)) {
+                        filesWithChangedSetOfUnresolvedImports.push(path);
+                        // reset log changes to avoid recording the same file multiple times
+                        logChanges = false;
+                    }
+                }
+                ts.Debug.assert(resolution !== undefined && !resolution.isInvalidated);
+                seenNamesInFile.set(name, true);
+                resolvedModules.push(getResolutionWithResolvedFileName(resolution)); // TODO: GH#18217
+            }
+            // Stop watching and remove the unused name
+            resolutionsInFile.forEach(function (resolution, name) {
+                if (!seenNamesInFile.has(name) && !ts.contains(reusedNames, name)) {
+                    stopWatchFailedLookupLocationOfResolution(resolution);
+                    resolutionsInFile.delete(name);
+                }
+            });
+            return resolvedModules;
+            function resolutionIsEqualTo(oldResolution, newResolution) {
+                if (oldResolution === newResolution) {
+                    return true;
+                }
+                if (!oldResolution || !newResolution) {
+                    return false;
+                }
+                var oldResult = getResolutionWithResolvedFileName(oldResolution);
+                var newResult = getResolutionWithResolvedFileName(newResolution);
+                if (oldResult === newResult) {
+                    return true;
+                }
+                if (!oldResult || !newResult) {
+                    return false;
+                }
+                return oldResult.resolvedFileName === newResult.resolvedFileName;
+            }
+        }
+        function resolveTypeReferenceDirectives(typeDirectiveNames, containingFile) {
+            return resolveNamesWithLocalCache(typeDirectiveNames, containingFile, resolvedTypeReferenceDirectives, perDirectoryResolvedTypeReferenceDirectives, ts.resolveTypeReferenceDirective, getResolvedTypeReferenceDirective, 
+            /*reusedNames*/ undefined, /*logChanges*/ false);
+        }
+        function resolveModuleNames(moduleNames, containingFile, reusedNames) {
+            return resolveNamesWithLocalCache(moduleNames, containingFile, resolvedModuleNames, perDirectoryResolvedModuleNames, resolveModuleName, getResolvedModule, reusedNames, logChangesWhenResolvingModule);
+        }
+        function getResolvedModuleWithFailedLookupLocationsFromCache(moduleName, containingFile) {
+            var cache = resolvedModuleNames.get(resolutionHost.toPath(containingFile));
+            return cache && cache.get(moduleName);
+        }
+        function isNodeModulesDirectory(dirPath) {
+            return ts.endsWith(dirPath, "/node_modules");
+        }
+        function isNodeModulesAtTypesDirectory(dirPath) {
+            return ts.endsWith(dirPath, "/node_modules/@types");
+        }
+        /**
+         * Filter out paths like
+         * "/", "/user", "/user/username", "/user/username/folderAtRoot",
+         * "c:/", "c:/users", "c:/users/username", "c:/users/username/folderAtRoot", "c:/folderAtRoot"
+         * @param dirPath
+         */
+        function canWatchDirectory(dirPath) {
+            var rootLength = ts.getRootLength(dirPath);
+            if (dirPath.length === rootLength) {
+                // Ignore "/", "c:/"
+                return false;
+            }
+            var nextDirectorySeparator = dirPath.indexOf(ts.directorySeparator, rootLength);
+            if (nextDirectorySeparator === -1) {
+                // ignore "/user", "c:/users" or "c:/folderAtRoot"
+                return false;
+            }
+            if (dirPath.charCodeAt(0) !== 47 /* slash */ &&
+                dirPath.substr(rootLength, nextDirectorySeparator).search(/users/i) === -1) {
+                // Paths like c:/folderAtRoot/subFolder are allowed
+                return true;
+            }
+            for (var searchIndex = nextDirectorySeparator + 1, searchLevels = 2; searchLevels > 0; searchLevels--) {
+                searchIndex = dirPath.indexOf(ts.directorySeparator, searchIndex) + 1;
+                if (searchIndex === 0) {
+                    // Folder isnt at expected minimun levels
+                    return false;
+                }
+            }
+            return true;
+        }
+        function filterFSRootDirectoriesToWatch(watchPath, dirPath) {
+            if (!canWatchDirectory(dirPath)) {
+                watchPath.ignore = true;
+            }
+            return watchPath;
+        }
+        function getDirectoryToWatchFailedLookupLocation(failedLookupLocation, failedLookupLocationPath) {
+            if (isInDirectoryPath(rootPath, failedLookupLocationPath)) {
+                return { dir: rootDir, dirPath: rootPath }; // TODO: GH#18217
+            }
+            return getDirectoryToWatchFromFailedLookupLocationDirectory(ts.getDirectoryPath(ts.getNormalizedAbsolutePath(failedLookupLocation, getCurrentDirectory())), ts.getDirectoryPath(failedLookupLocationPath));
+        }
+        function getDirectoryToWatchFromFailedLookupLocationDirectory(dir, dirPath) {
+            // If directory path contains node module, get the most parent node_modules directory for watching
+            while (ts.stringContains(dirPath, "/node_modules/")) {
+                dir = ts.getDirectoryPath(dir);
+                dirPath = ts.getDirectoryPath(dirPath);
+            }
+            // If the directory is node_modules use it to watch
+            if (isNodeModulesDirectory(dirPath)) {
+                return filterFSRootDirectoriesToWatch({ dir: dir, dirPath: dirPath }, ts.getDirectoryPath(dirPath));
+            }
+            // Use some ancestor of the root directory
+            var subDirectoryPath, subDirectory;
+            if (rootPath !== undefined) {
+                while (!isInDirectoryPath(dirPath, rootPath)) {
+                    var parentPath = ts.getDirectoryPath(dirPath);
+                    if (parentPath === dirPath) {
+                        break;
+                    }
+                    subDirectoryPath = dirPath;
+                    subDirectory = dir;
+                    dirPath = parentPath;
+                    dir = ts.getDirectoryPath(dir);
+                }
+            }
+            return filterFSRootDirectoriesToWatch({ dir: subDirectory || dir, dirPath: subDirectoryPath || dirPath }, dirPath);
+        }
+        function isPathWithDefaultFailedLookupExtension(path) {
+            return ts.fileExtensionIsOneOf(path, failedLookupDefaultExtensions);
+        }
+        function watchFailedLookupLocationOfResolution(resolution) {
+            // No need to set the resolution refCount
+            if (!resolution.failedLookupLocations || !resolution.failedLookupLocations.length) {
+                return;
+            }
+            if (resolution.refCount !== undefined) {
+                resolution.refCount++;
+                return;
+            }
+            resolution.refCount = 1;
+            var failedLookupLocations = resolution.failedLookupLocations;
+            var setAtRoot = false;
+            for (var _i = 0, failedLookupLocations_1 = failedLookupLocations; _i < failedLookupLocations_1.length; _i++) {
+                var failedLookupLocation = failedLookupLocations_1[_i];
+                var failedLookupLocationPath = resolutionHost.toPath(failedLookupLocation);
+                var _a = getDirectoryToWatchFailedLookupLocation(failedLookupLocation, failedLookupLocationPath), dir = _a.dir, dirPath = _a.dirPath, ignore = _a.ignore;
+                if (!ignore) {
+                    // If the failed lookup location path is not one of the supported extensions,
+                    // store it in the custom path
+                    if (!isPathWithDefaultFailedLookupExtension(failedLookupLocationPath)) {
+                        var refCount = customFailedLookupPaths.get(failedLookupLocationPath) || 0;
+                        customFailedLookupPaths.set(failedLookupLocationPath, refCount + 1);
+                    }
+                    if (dirPath === rootPath) {
+                        setAtRoot = true;
+                    }
+                    else {
+                        setDirectoryWatcher(dir, dirPath);
+                    }
+                }
+            }
+            if (setAtRoot) {
+                setDirectoryWatcher(rootDir, rootPath); // TODO: GH#18217
+            }
+        }
+        function setDirectoryWatcher(dir, dirPath) {
+            var dirWatcher = directoryWatchesOfFailedLookups.get(dirPath);
+            if (dirWatcher) {
+                dirWatcher.refCount++;
+            }
+            else {
+                directoryWatchesOfFailedLookups.set(dirPath, { watcher: createDirectoryWatcher(dir, dirPath), refCount: 1 });
+            }
+        }
+        function stopWatchFailedLookupLocationOfResolution(resolution) {
+            if (!resolution.failedLookupLocations || !resolution.failedLookupLocations.length) {
+                return;
+            }
+            resolution.refCount--;
+            if (resolution.refCount) {
+                return;
+            }
+            var failedLookupLocations = resolution.failedLookupLocations;
+            var removeAtRoot = false;
+            for (var _i = 0, failedLookupLocations_2 = failedLookupLocations; _i < failedLookupLocations_2.length; _i++) {
+                var failedLookupLocation = failedLookupLocations_2[_i];
+                var failedLookupLocationPath = resolutionHost.toPath(failedLookupLocation);
+                var _a = getDirectoryToWatchFailedLookupLocation(failedLookupLocation, failedLookupLocationPath), dirPath = _a.dirPath, ignore = _a.ignore;
+                if (!ignore) {
+                    var refCount = customFailedLookupPaths.get(failedLookupLocationPath);
+                    if (refCount) {
+                        if (refCount === 1) {
+                            customFailedLookupPaths.delete(failedLookupLocationPath);
+                        }
+                        else {
+                            ts.Debug.assert(refCount > 1);
+                            customFailedLookupPaths.set(failedLookupLocationPath, refCount - 1);
+                        }
+                    }
+                    if (dirPath === rootPath) {
+                        removeAtRoot = true;
+                    }
+                    else {
+                        removeDirectoryWatcher(dirPath);
+                    }
+                }
+            }
+            if (removeAtRoot) {
+                removeDirectoryWatcher(rootPath);
+            }
+        }
+        function removeDirectoryWatcher(dirPath) {
+            var dirWatcher = directoryWatchesOfFailedLookups.get(dirPath);
+            // Do not close the watcher yet since it might be needed by other failed lookup locations.
+            dirWatcher.refCount--;
+        }
+        function createDirectoryWatcher(directory, dirPath) {
+            return resolutionHost.watchDirectoryOfFailedLookupLocation(directory, function (fileOrDirectory) {
+                var fileOrDirectoryPath = resolutionHost.toPath(fileOrDirectory);
+                if (cachedDirectoryStructureHost) {
+                    // Since the file existence changed, update the sourceFiles cache
+                    cachedDirectoryStructureHost.addOrDeleteFileOrDirectory(fileOrDirectory, fileOrDirectoryPath);
+                }
+                if (!allFilesHaveInvalidatedResolution && invalidateResolutionOfFailedLookupLocation(fileOrDirectoryPath, dirPath === fileOrDirectoryPath)) {
+                    resolutionHost.onInvalidatedResolution();
+                }
+            }, 1 /* Recursive */);
+        }
+        function removeResolutionsOfFileFromCache(cache, filePath) {
+            // Deleted file, stop watching failed lookups for all the resolutions in the file
+            var resolutions = cache.get(filePath);
+            if (resolutions) {
+                resolutions.forEach(stopWatchFailedLookupLocationOfResolution);
+                cache.delete(filePath);
+            }
+        }
+        function removeResolutionsOfFile(filePath) {
+            removeResolutionsOfFileFromCache(resolvedModuleNames, filePath);
+            removeResolutionsOfFileFromCache(resolvedTypeReferenceDirectives, filePath);
+        }
+        function invalidateResolutionCache(cache, isInvalidatedResolution, getResolutionWithResolvedFileName) {
+            var seen = ts.createMap();
+            cache.forEach(function (resolutions, containingFilePath) {
+                var dirPath = ts.getDirectoryPath(containingFilePath);
+                var seenInDir = seen.get(dirPath);
+                if (!seenInDir) {
+                    seenInDir = ts.createMap();
+                    seen.set(dirPath, seenInDir);
+                }
+                resolutions.forEach(function (resolution, name) {
+                    if (seenInDir.has(name)) {
+                        return;
+                    }
+                    seenInDir.set(name, true);
+                    if (!resolution.isInvalidated && isInvalidatedResolution(resolution, getResolutionWithResolvedFileName)) {
+                        // Mark the file as needing re-evaluation of module resolution instead of using it blindly.
+                        resolution.isInvalidated = true;
+                        (filesWithInvalidatedResolutions || (filesWithInvalidatedResolutions = ts.createMap())).set(containingFilePath, true);
+                    }
+                });
+            });
+        }
+        function hasReachedResolutionIterationLimit() {
+            var maxSize = resolutionHost.maxNumberOfFilesToIterateForInvalidation || ts.maxNumberOfFilesToIterateForInvalidation;
+            return resolvedModuleNames.size > maxSize || resolvedTypeReferenceDirectives.size > maxSize;
+        }
+        function invalidateResolutions(isInvalidatedResolution) {
+            // If more than maxNumberOfFilesToIterateForInvalidation present,
+            // just invalidated all files and recalculate the resolutions for files instead
+            if (hasReachedResolutionIterationLimit()) {
+                allFilesHaveInvalidatedResolution = true;
+                return;
+            }
+            invalidateResolutionCache(resolvedModuleNames, isInvalidatedResolution, getResolvedModule);
+            invalidateResolutionCache(resolvedTypeReferenceDirectives, isInvalidatedResolution, getResolvedTypeReferenceDirective);
+        }
+        function invalidateResolutionOfFile(filePath) {
+            removeResolutionsOfFile(filePath);
+            invalidateResolutions(
+            // Resolution is invalidated if the resulting file name is same as the deleted file path
+            function (resolution, getResolutionWithResolvedFileName) {
+                var result = getResolutionWithResolvedFileName(resolution);
+                return !!result && resolutionHost.toPath(result.resolvedFileName) === filePath; // TODO: GH#18217
+            });
+        }
+        function setFilesWithInvalidatedNonRelativeUnresolvedImports(filesMap) {
+            ts.Debug.assert(filesWithInvalidatedNonRelativeUnresolvedImports === filesMap || filesWithInvalidatedNonRelativeUnresolvedImports === undefined);
+            filesWithInvalidatedNonRelativeUnresolvedImports = filesMap;
+        }
+        function invalidateResolutionOfFailedLookupLocation(fileOrDirectoryPath, isCreatingWatchedDirectory) {
+            var isChangedFailedLookupLocation;
+            if (isCreatingWatchedDirectory) {
+                // Watching directory is created
+                // Invalidate any resolution has failed lookup in this directory
+                isChangedFailedLookupLocation = function (location) { return isInDirectoryPath(fileOrDirectoryPath, resolutionHost.toPath(location)); };
+            }
+            else {
+                // Some file or directory in the watching directory is created
+                // Return early if it does not have any of the watching extension or not the custom failed lookup path
+                var dirOfFileOrDirectory = ts.getDirectoryPath(fileOrDirectoryPath);
+                if (isNodeModulesAtTypesDirectory(fileOrDirectoryPath) || isNodeModulesDirectory(fileOrDirectoryPath) ||
+                    isNodeModulesAtTypesDirectory(dirOfFileOrDirectory) || isNodeModulesDirectory(dirOfFileOrDirectory)) {
+                    // Invalidate any resolution from this directory
+                    isChangedFailedLookupLocation = function (location) {
+                        var locationPath = resolutionHost.toPath(location);
+                        return locationPath === fileOrDirectoryPath || ts.startsWith(resolutionHost.toPath(location), fileOrDirectoryPath);
+                    };
+                }
+                else {
+                    if (!isPathWithDefaultFailedLookupExtension(fileOrDirectoryPath) && !customFailedLookupPaths.has(fileOrDirectoryPath)) {
+                        return false;
+                    }
+                    // Ignore emits from the program
+                    if (ts.isEmittedFileOfProgram(resolutionHost.getCurrentProgram(), fileOrDirectoryPath)) {
+                        return false;
+                    }
+                    // Resolution need to be invalidated if failed lookup location is same as the file or directory getting created
+                    isChangedFailedLookupLocation = function (location) { return resolutionHost.toPath(location) === fileOrDirectoryPath; };
+                }
+            }
+            var hasChangedFailedLookupLocation = function (resolution) { return ts.some(resolution.failedLookupLocations, isChangedFailedLookupLocation); };
+            var invalidatedFilesCount = filesWithInvalidatedResolutions && filesWithInvalidatedResolutions.size;
+            invalidateResolutions(
+            // Resolution is invalidated if the resulting file name is same as the deleted file path
+            hasChangedFailedLookupLocation);
+            return allFilesHaveInvalidatedResolution || filesWithInvalidatedResolutions && filesWithInvalidatedResolutions.size !== invalidatedFilesCount;
+        }
+        function closeTypeRootsWatch() {
+            ts.clearMap(typeRootsWatches, ts.closeFileWatcher);
+        }
+        function getDirectoryToWatchFailedLookupLocationFromTypeRoot(typeRoot, typeRootPath) {
+            if (allFilesHaveInvalidatedResolution) {
+                return undefined;
+            }
+            if (isInDirectoryPath(rootPath, typeRootPath)) {
+                return rootPath;
+            }
+            var _a = getDirectoryToWatchFromFailedLookupLocationDirectory(typeRoot, typeRootPath), dirPath = _a.dirPath, ignore = _a.ignore;
+            return !ignore && directoryWatchesOfFailedLookups.has(dirPath) ? dirPath : undefined;
+        }
+        function createTypeRootsWatch(typeRootPath, typeRoot) {
+            // Create new watch and recursive info
+            return resolutionHost.watchTypeRootsDirectory(typeRoot, function (fileOrDirectory) {
+                var fileOrDirectoryPath = resolutionHost.toPath(fileOrDirectory);
+                if (cachedDirectoryStructureHost) {
+                    // Since the file existence changed, update the sourceFiles cache
+                    cachedDirectoryStructureHost.addOrDeleteFileOrDirectory(fileOrDirectory, fileOrDirectoryPath);
+                }
+                // For now just recompile
+                // We could potentially store more data here about whether it was/would be really be used or not
+                // and with that determine to trigger compilation but for now this is enough
+                resolutionHost.onChangedAutomaticTypeDirectiveNames();
+                // Since directory watchers invoked are flaky, the failed lookup location events might not be triggered
+                // So handle to failed lookup locations here as well to ensure we are invalidating resolutions
+                var dirPath = getDirectoryToWatchFailedLookupLocationFromTypeRoot(typeRoot, typeRootPath);
+                if (dirPath && invalidateResolutionOfFailedLookupLocation(fileOrDirectoryPath, dirPath === fileOrDirectoryPath)) {
+                    resolutionHost.onInvalidatedResolution();
+                }
+            }, 1 /* Recursive */);
+        }
+        /**
+         * Watches the types that would get added as part of getAutomaticTypeDirectiveNames
+         * To be called when compiler options change
+         */
+        function updateTypeRootsWatch() {
+            var options = resolutionHost.getCompilationSettings();
+            if (options.types) {
+                // No need to do any watch since resolution cache is going to handle the failed lookups
+                // for the types added by this
+                closeTypeRootsWatch();
+                return;
+            }
+            // we need to assume the directories exist to ensure that we can get all the type root directories that get included
+            // But filter directories that are at root level to say directory doesnt exist, so that we arent watching them
+            var typeRoots = ts.getEffectiveTypeRoots(options, { directoryExists: directoryExistsForTypeRootWatch, getCurrentDirectory: getCurrentDirectory });
+            if (typeRoots) {
+                ts.mutateMap(typeRootsWatches, ts.arrayToMap(typeRoots, function (tr) { return resolutionHost.toPath(tr); }), {
+                    createNewValue: createTypeRootsWatch,
+                    onDeleteValue: ts.closeFileWatcher
+                });
+            }
+            else {
+                closeTypeRootsWatch();
+            }
+        }
+        /**
+         * Use this function to return if directory exists to get type roots to watch
+         * If we return directory exists then only the paths will be added to type roots
+         * Hence return true for all directories except root directories which are filtered from watching
+         */
+        function directoryExistsForTypeRootWatch(nodeTypesDirectory) {
+            var dir = ts.getDirectoryPath(ts.getDirectoryPath(nodeTypesDirectory));
+            var dirPath = resolutionHost.toPath(dir);
+            return dirPath === rootPath || canWatchDirectory(dirPath);
+        }
+    }
+    ts.createResolutionCache = createResolutionCache;
+})(ts || (ts = {}));
+// Used by importFixes to synthesize import module specifiers.
+/* @internal */
+var ts;
+(function (ts) {
+    var moduleSpecifiers;
+    (function (moduleSpecifiers) {
+        // Note: fromSourceFile is just for usesJsExtensionOnImports
+        function getModuleSpecifier(compilerOptions, fromSourceFile, fromSourceFileName, toFileName, host, preferences) {
+            if (preferences === void 0) { preferences = {}; }
+            var info = getInfo(compilerOptions, fromSourceFile, fromSourceFileName, host);
+            return getGlobalModuleSpecifier(toFileName, info, host, compilerOptions) ||
+                ts.first(getLocalModuleSpecifiers(toFileName, info, compilerOptions, preferences));
+        }
+        moduleSpecifiers.getModuleSpecifier = getModuleSpecifier;
+        // For each symlink/original for a module, returns a list of ways to import that file.
+        function getModuleSpecifiers(moduleSymbol, program, importingSourceFile, host, preferences) {
+            var ambient = tryGetModuleNameFromAmbientModule(moduleSymbol);
+            if (ambient)
+                return [[ambient]];
+            var compilerOptions = program.getCompilerOptions();
+            var info = getInfo(compilerOptions, importingSourceFile, importingSourceFile.fileName, host);
+            var modulePaths = getAllModulePaths(program, ts.getSourceFileOfNode(moduleSymbol.valueDeclaration));
+            var global = ts.mapDefined(modulePaths, function (moduleFileName) { return getGlobalModuleSpecifier(moduleFileName, info, host, compilerOptions); });
+            return global.length ? global.map(function (g) { return [g]; }) : modulePaths.map(function (moduleFileName) {
+                return getLocalModuleSpecifiers(moduleFileName, info, compilerOptions, preferences);
+            });
+        }
+        moduleSpecifiers.getModuleSpecifiers = getModuleSpecifiers;
+        // importingSourceFileName is separate because getEditsForFileRename may need to specify an updated path
+        function getInfo(compilerOptions, importingSourceFile, importingSourceFileName, host) {
+            var moduleResolutionKind = ts.getEmitModuleResolutionKind(compilerOptions);
+            var addJsExtension = usesJsExtensionOnImports(importingSourceFile);
+            var getCanonicalFileName = ts.createGetCanonicalFileName(host.useCaseSensitiveFileNames ? host.useCaseSensitiveFileNames() : true);
+            var sourceDirectory = ts.getDirectoryPath(importingSourceFileName);
+            return { moduleResolutionKind: moduleResolutionKind, addJsExtension: addJsExtension, getCanonicalFileName: getCanonicalFileName, sourceDirectory: sourceDirectory };
+        }
+        function getGlobalModuleSpecifier(moduleFileName, _a, host, compilerOptions) {
+            var addJsExtension = _a.addJsExtension, getCanonicalFileName = _a.getCanonicalFileName, sourceDirectory = _a.sourceDirectory;
+            return tryGetModuleNameFromTypeRoots(compilerOptions, host, getCanonicalFileName, moduleFileName, addJsExtension)
+                || tryGetModuleNameAsNodeModule(compilerOptions, moduleFileName, host, getCanonicalFileName, sourceDirectory)
+                || compilerOptions.rootDirs && tryGetModuleNameFromRootDirs(compilerOptions.rootDirs, moduleFileName, sourceDirectory, getCanonicalFileName);
+        }
+        function getLocalModuleSpecifiers(moduleFileName, _a, compilerOptions, preferences) {
+            var moduleResolutionKind = _a.moduleResolutionKind, addJsExtension = _a.addJsExtension, getCanonicalFileName = _a.getCanonicalFileName, sourceDirectory = _a.sourceDirectory;
+            var baseUrl = compilerOptions.baseUrl, paths = compilerOptions.paths;
+            var relativePath = removeExtensionAndIndexPostFix(ts.ensurePathIsNonModuleName(ts.getRelativePathFromDirectory(sourceDirectory, moduleFileName, getCanonicalFileName)), moduleResolutionKind, addJsExtension);
+            if (!baseUrl || preferences.importModuleSpecifierPreference === "relative") {
+                return [relativePath];
+            }
+            var relativeToBaseUrl = getRelativePathIfInDirectory(moduleFileName, baseUrl, getCanonicalFileName);
+            if (!relativeToBaseUrl) {
+                return [relativePath];
+            }
+            var importRelativeToBaseUrl = removeExtensionAndIndexPostFix(relativeToBaseUrl, moduleResolutionKind, addJsExtension);
+            if (paths) {
+                var fromPaths = tryGetModuleNameFromPaths(ts.removeFileExtension(relativeToBaseUrl), importRelativeToBaseUrl, paths);
+                if (fromPaths) {
+                    return [fromPaths];
+                }
+            }
+            if (preferences.importModuleSpecifierPreference === "non-relative") {
+                return [importRelativeToBaseUrl];
+            }
+            if (preferences.importModuleSpecifierPreference !== undefined)
+                ts.Debug.assertNever(preferences.importModuleSpecifierPreference);
+            if (isPathRelativeToParent(relativeToBaseUrl)) {
+                return [relativePath];
+            }
+            /*
+            Prefer a relative import over a baseUrl import if it doesn't traverse up to baseUrl.
+    
+            Suppose we have:
+                baseUrl = /base
+                sourceDirectory = /base/a/b
+                moduleFileName = /base/foo/bar
+            Then:
+                relativePath = ../../foo/bar
+                getRelativePathNParents(relativePath) = 2
+                pathFromSourceToBaseUrl = ../../
+                getRelativePathNParents(pathFromSourceToBaseUrl) = 2
+                2 < 2 = false
+            In this case we should prefer using the baseUrl path "/a/b" instead of the relative path "../../foo/bar".
+    
+            Suppose we have:
+                baseUrl = /base
+                sourceDirectory = /base/foo/a
+                moduleFileName = /base/foo/bar
+            Then:
+                relativePath = ../a
+                getRelativePathNParents(relativePath) = 1
+                pathFromSourceToBaseUrl = ../../
+                getRelativePathNParents(pathFromSourceToBaseUrl) = 2
+                1 < 2 = true
+            In this case we should prefer using the relative path "../a" instead of the baseUrl path "foo/a".
+            */
+            var pathFromSourceToBaseUrl = ts.ensurePathIsNonModuleName(ts.getRelativePathFromDirectory(sourceDirectory, baseUrl, getCanonicalFileName));
+            var relativeFirst = getRelativePathNParents(relativePath) < getRelativePathNParents(pathFromSourceToBaseUrl);
+            return relativeFirst ? [relativePath, importRelativeToBaseUrl] : [importRelativeToBaseUrl, relativePath];
+        }
+        function usesJsExtensionOnImports(_a) {
+            var imports = _a.imports;
+            return ts.firstDefined(imports, function (_a) {
+                var text = _a.text;
+                return ts.pathIsRelative(text) ? ts.fileExtensionIs(text, ".js" /* Js */) : undefined;
+            }) || false;
+        }
+        /**
+         * Looks for a existing imports that use symlinks to this module.
+         * Only if no symlink is available, the real path will be used.
+         */
+        function getAllModulePaths(program, _a) {
+            var fileName = _a.fileName;
+            var symlinks = ts.mapDefined(program.getSourceFiles(), function (sf) {
+                return sf.resolvedModules && ts.firstDefinedIterator(sf.resolvedModules.values(), function (res) {
+                    return res && res.resolvedFileName === fileName ? res.originalPath : undefined;
+                });
+            });
+            return symlinks.length === 0 ? [fileName] : symlinks;
+        }
+        function getRelativePathNParents(relativePath) {
+            var components = ts.getPathComponents(relativePath);
+            if (components[0] || components.length === 1)
+                return 0;
+            for (var i = 1; i < components.length; i++) {
+                if (components[i] !== "..")
+                    return i - 1;
+            }
+            return components.length - 1;
+        }
+        function tryGetModuleNameFromAmbientModule(moduleSymbol) {
+            var decl = moduleSymbol.valueDeclaration;
+            if (ts.isModuleDeclaration(decl) && ts.isStringLiteral(decl.name)) {
+                return decl.name.text;
+            }
+        }
+        function tryGetModuleNameFromPaths(relativeToBaseUrlWithIndex, relativeToBaseUrl, paths) {
+            for (var key in paths) {
+                for (var _i = 0, _a = paths[key]; _i < _a.length; _i++) {
+                    var patternText_1 = _a[_i];
+                    var pattern = ts.removeFileExtension(ts.normalizePath(patternText_1));
+                    var indexOfStar = pattern.indexOf("*");
+                    if (indexOfStar === 0 && pattern.length === 1) {
+                        continue;
+                    }
+                    else if (indexOfStar !== -1) {
+                        var prefix = pattern.substr(0, indexOfStar);
+                        var suffix = pattern.substr(indexOfStar + 1);
+                        if (relativeToBaseUrl.length >= prefix.length + suffix.length &&
+                            ts.startsWith(relativeToBaseUrl, prefix) &&
+                            ts.endsWith(relativeToBaseUrl, suffix)) {
+                            var matchedStar = relativeToBaseUrl.substr(prefix.length, relativeToBaseUrl.length - suffix.length);
+                            return key.replace("*", matchedStar);
+                        }
+                    }
+                    else if (pattern === relativeToBaseUrl || pattern === relativeToBaseUrlWithIndex) {
+                        return key;
+                    }
+                }
+            }
+        }
+        function tryGetModuleNameFromRootDirs(rootDirs, moduleFileName, sourceDirectory, getCanonicalFileName) {
+            var normalizedTargetPath = getPathRelativeToRootDirs(moduleFileName, rootDirs, getCanonicalFileName);
+            if (normalizedTargetPath === undefined) {
+                return undefined;
+            }
+            var normalizedSourcePath = getPathRelativeToRootDirs(sourceDirectory, rootDirs, getCanonicalFileName);
+            var relativePath = normalizedSourcePath !== undefined ? ts.ensurePathIsNonModuleName(ts.getRelativePathFromDirectory(normalizedSourcePath, normalizedTargetPath, getCanonicalFileName)) : normalizedTargetPath;
+            return ts.removeFileExtension(relativePath);
+        }
+        function tryGetModuleNameFromTypeRoots(options, host, getCanonicalFileName, moduleFileName, addJsExtension) {
+            var roots = ts.getEffectiveTypeRoots(options, host);
+            return ts.firstDefined(roots, function (unNormalizedTypeRoot) {
+                var typeRoot = ts.toPath(unNormalizedTypeRoot, /*basePath*/ undefined, getCanonicalFileName);
+                if (ts.startsWith(moduleFileName, typeRoot)) {
+                    // For a type definition, we can strip `/index` even with classic resolution.
+                    return removeExtensionAndIndexPostFix(moduleFileName.substring(typeRoot.length + 1), ts.ModuleResolutionKind.NodeJs, addJsExtension);
+                }
+            });
+        }
+        function tryGetModuleNameAsNodeModule(options, moduleFileName, host, getCanonicalFileName, sourceDirectory) {
+            if (ts.getEmitModuleResolutionKind(options) !== ts.ModuleResolutionKind.NodeJs) {
+                // nothing to do here
+                return undefined;
+            }
+            var parts = getNodeModulePathParts(moduleFileName);
+            if (!parts) {
+                return undefined;
+            }
+            // Simplify the full file path to something that can be resolved by Node.
+            // If the module could be imported by a directory name, use that directory's name
+            var moduleSpecifier = getDirectoryOrExtensionlessFileName(moduleFileName);
+            // Get a path that's relative to node_modules or the importing file's path
+            // if node_modules folder is in this folder or any of its parent folders, no need to keep it.
+            if (!ts.startsWith(sourceDirectory, moduleSpecifier.substring(0, parts.topLevelNodeModulesIndex)))
+                return undefined;
+            // If the module was found in @types, get the actual Node package name
+            return ts.getPackageNameFromAtTypesDirectory(moduleSpecifier.substring(parts.topLevelPackageNameIndex + 1));
+            function getDirectoryOrExtensionlessFileName(path) {
+                // If the file is the main module, it can be imported by the package name
+                var packageRootPath = path.substring(0, parts.packageRootIndex);
+                var packageJsonPath = ts.combinePaths(packageRootPath, "package.json");
+                if (host.fileExists(packageJsonPath)) { // TODO: GH#18217
+                    var packageJsonContent = JSON.parse(host.readFile(packageJsonPath));
+                    if (packageJsonContent) {
+                        var mainFileRelative = packageJsonContent.typings || packageJsonContent.types || packageJsonContent.main;
+                        if (mainFileRelative) {
+                            var mainExportFile = ts.toPath(mainFileRelative, packageRootPath, getCanonicalFileName);
+                            if (ts.removeFileExtension(mainExportFile) === ts.removeFileExtension(getCanonicalFileName(path))) {
+                                return packageRootPath;
+                            }
+                        }
+                    }
+                }
+                // We still have a file name - remove the extension
+                var fullModulePathWithoutExtension = ts.removeFileExtension(path);
+                // If the file is /index, it can be imported by its directory name
+                // IFF there is not _also_ a file by the same name
+                if (getCanonicalFileName(fullModulePathWithoutExtension.substring(parts.fileNameIndex)) === "/index" && !tryGetAnyFileFromPath(host, fullModulePathWithoutExtension.substring(0, parts.fileNameIndex))) {
+                    return fullModulePathWithoutExtension.substring(0, parts.fileNameIndex);
+                }
+                return fullModulePathWithoutExtension;
+            }
+        }
+        function tryGetAnyFileFromPath(host, path) {
+            // We check all js, `node` and `json` extensions in addition to TS, since node module resolution would also choose those over the directory
+            var extensions = ts.getSupportedExtensions({ allowJs: true }, [{ extension: "node", isMixedContent: false }, { extension: "json", isMixedContent: false, scriptKind: 6 /* JSON */ }]);
+            for (var _i = 0, extensions_3 = extensions; _i < extensions_3.length; _i++) {
+                var e = extensions_3[_i];
+                var fullPath = path + e;
+                if (host.fileExists(fullPath)) { // TODO: GH#18217
+                    return fullPath;
+                }
+            }
+        }
+        function getNodeModulePathParts(fullPath) {
+            // If fullPath can't be valid module file within node_modules, returns undefined.
+            // Example of expected pattern: /base/path/node_modules/[@scope/otherpackage/@otherscope/node_modules/]package/[subdirectory/]file.js
+            // Returns indices:                       ^            ^                                                      ^             ^
+            var topLevelNodeModulesIndex = 0;
+            var topLevelPackageNameIndex = 0;
+            var packageRootIndex = 0;
+            var fileNameIndex = 0;
+            var States;
+            (function (States) {
+                States[States["BeforeNodeModules"] = 0] = "BeforeNodeModules";
+                States[States["NodeModules"] = 1] = "NodeModules";
+                States[States["Scope"] = 2] = "Scope";
+                States[States["PackageContent"] = 3] = "PackageContent";
+            })(States || (States = {}));
+            var partStart = 0;
+            var partEnd = 0;
+            var state = 0 /* BeforeNodeModules */;
+            while (partEnd >= 0) {
+                partStart = partEnd;
+                partEnd = fullPath.indexOf("/", partStart + 1);
+                switch (state) {
+                    case 0 /* BeforeNodeModules */:
+                        if (fullPath.indexOf("/node_modules/", partStart) === partStart) {
+                            topLevelNodeModulesIndex = partStart;
+                            topLevelPackageNameIndex = partEnd;
+                            state = 1 /* NodeModules */;
+                        }
+                        break;
+                    case 1 /* NodeModules */:
+                    case 2 /* Scope */:
+                        if (state === 1 /* NodeModules */ && fullPath.charAt(partStart + 1) === "@") {
+                            state = 2 /* Scope */;
+                        }
+                        else {
+                            packageRootIndex = partEnd;
+                            state = 3 /* PackageContent */;
+                        }
+                        break;
+                    case 3 /* PackageContent */:
+                        if (fullPath.indexOf("/node_modules/", partStart) === partStart) {
+                            state = 1 /* NodeModules */;
+                        }
+                        else {
+                            state = 3 /* PackageContent */;
+                        }
+                        break;
+                }
+            }
+            fileNameIndex = partStart;
+            return state > 1 /* NodeModules */ ? { topLevelNodeModulesIndex: topLevelNodeModulesIndex, topLevelPackageNameIndex: topLevelPackageNameIndex, packageRootIndex: packageRootIndex, fileNameIndex: fileNameIndex } : undefined;
+        }
+        function getPathRelativeToRootDirs(path, rootDirs, getCanonicalFileName) {
+            return ts.firstDefined(rootDirs, function (rootDir) {
+                var relativePath = getRelativePathIfInDirectory(path, rootDir, getCanonicalFileName); // TODO: GH#18217
+                return isPathRelativeToParent(relativePath) ? undefined : relativePath;
+            });
+        }
+        function removeExtensionAndIndexPostFix(fileName, moduleResolutionKind, addJsExtension) {
+            var noExtension = ts.removeFileExtension(fileName);
+            return addJsExtension
+                ? noExtension + ".js"
+                : moduleResolutionKind === ts.ModuleResolutionKind.NodeJs
+                    ? ts.removeSuffix(noExtension, "/index")
+                    : noExtension;
+        }
+        function getRelativePathIfInDirectory(path, directoryPath, getCanonicalFileName) {
+            var relativePath = ts.getRelativePathToDirectoryOrUrl(directoryPath, path, directoryPath, getCanonicalFileName, /*isAbsolutePathAnUrl*/ false);
+            return ts.isRootedDiskPath(relativePath) ? undefined : relativePath;
+        }
+        function isPathRelativeToParent(path) {
+            return ts.startsWith(path, "..");
+        }
+    })(moduleSpecifiers = ts.moduleSpecifiers || (ts.moduleSpecifiers = {}));
+})(ts || (ts = {}));
+/*@internal*/
+var ts;
+(function (ts) {
+    var sysFormatDiagnosticsHost = ts.sys ? {
+        getCurrentDirectory: function () { return ts.sys.getCurrentDirectory(); },
+        getNewLine: function () { return ts.sys.newLine; },
+        getCanonicalFileName: ts.createGetCanonicalFileName(ts.sys.useCaseSensitiveFileNames)
+    } : undefined; // TODO: GH#18217
+    /**
+     * Create a function that reports error by writing to the system and handles the formating of the diagnostic
+     */
+    function createDiagnosticReporter(system, pretty) {
+        var host = system === ts.sys ? sysFormatDiagnosticsHost : {
+            getCurrentDirectory: function () { return system.getCurrentDirectory(); },
+            getNewLine: function () { return system.newLine; },
+            getCanonicalFileName: ts.createGetCanonicalFileName(system.useCaseSensitiveFileNames),
+        };
+        if (!pretty) {
+            return function (diagnostic) { return system.write(ts.formatDiagnostic(diagnostic, host)); };
+        }
+        var diagnostics = new Array(1);
+        return function (diagnostic) {
+            diagnostics[0] = diagnostic;
+            system.write(ts.formatDiagnosticsWithColorAndContext(diagnostics, host) + host.getNewLine());
+            diagnostics[0] = undefined; // TODO: GH#18217
+        };
+    }
+    ts.createDiagnosticReporter = createDiagnosticReporter;
+    /** @internal */
+    ts.nonClearingMessageCodes = [
+        ts.Diagnostics.Found_1_error_Watching_for_file_changes.code,
+        ts.Diagnostics.Found_0_errors_Watching_for_file_changes.code
+    ];
+    /**
+     * @returns Whether the screen was cleared.
+     */
+    function clearScreenIfNotWatchingForFileChanges(system, diagnostic, options) {
+        if (system.clearScreen &&
+            !options.preserveWatchOutput &&
+            !options.extendedDiagnostics &&
+            !options.diagnostics &&
+            !ts.contains(ts.nonClearingMessageCodes, diagnostic.code)) {
+            system.clearScreen();
+            return true;
+        }
+        return false;
+    }
+    /** @internal */
+    ts.screenStartingMessageCodes = [
+        ts.Diagnostics.Starting_compilation_in_watch_mode.code,
+        ts.Diagnostics.File_change_detected_Starting_incremental_compilation.code,
+    ];
+    function getPlainDiagnosticFollowingNewLines(diagnostic, newLine) {
+        return ts.contains(ts.screenStartingMessageCodes, diagnostic.code)
+            ? newLine + newLine
+            : newLine;
+    }
+    /**
+     * Create a function that reports watch status by writing to the system and handles the formating of the diagnostic
+     */
+    function createWatchStatusReporter(system, pretty) {
+        return pretty ?
+            function (diagnostic, newLine, options) {
+                clearScreenIfNotWatchingForFileChanges(system, diagnostic, options);
+                var output = "[" + ts.formatColorAndReset(new Date().toLocaleTimeString(), ts.ForegroundColorEscapeSequences.Grey) + "] ";
+                output += "" + ts.flattenDiagnosticMessageText(diagnostic.messageText, system.newLine) + (newLine + newLine);
+                system.write(output);
+            } :
+            function (diagnostic, newLine, options) {
+                var output = "";
+                if (!clearScreenIfNotWatchingForFileChanges(system, diagnostic, options)) {
+                    output += newLine;
+                }
+                output += new Date().toLocaleTimeString() + " - ";
+                output += "" + ts.flattenDiagnosticMessageText(diagnostic.messageText, system.newLine) + getPlainDiagnosticFollowingNewLines(diagnostic, newLine);
+                system.write(output);
+            };
+    }
+    ts.createWatchStatusReporter = createWatchStatusReporter;
+    /** Parses config file using System interface */
+    function parseConfigFileWithSystem(configFileName, optionsToExtend, system, reportDiagnostic) {
+        var host = system;
+        host.onUnRecoverableConfigFileDiagnostic = function (diagnostic) { return reportUnrecoverableDiagnostic(ts.sys, reportDiagnostic, diagnostic); };
+        var result = ts.getParsedCommandLineOfConfigFile(configFileName, optionsToExtend, host);
+        host.onUnRecoverableConfigFileDiagnostic = undefined; // TODO: GH#18217
+        return result;
+    }
+    ts.parseConfigFileWithSystem = parseConfigFileWithSystem;
+    /**
+     * Helper that emit files, report diagnostics and lists emitted and/or source files depending on compiler options
+     */
+    function emitFilesAndReportErrors(program, reportDiagnostic, writeFileName, reportSummary) {
+        // First get and report any syntactic errors.
+        var diagnostics = program.getConfigFileParsingDiagnostics().slice();
+        var configFileParsingDiagnosticsLength = diagnostics.length;
+        ts.addRange(diagnostics, program.getSyntacticDiagnostics());
+        var reportSemanticDiagnostics = false;
+        // If we didn't have any syntactic errors, then also try getting the global and
+        // semantic errors.
+        if (diagnostics.length === configFileParsingDiagnosticsLength) {
+            ts.addRange(diagnostics, program.getOptionsDiagnostics());
+            ts.addRange(diagnostics, program.getGlobalDiagnostics());
+            if (diagnostics.length === configFileParsingDiagnosticsLength) {
+                reportSemanticDiagnostics = true;
+            }
+        }
+        // Emit and report any errors we ran into.
+        var _a = program.emit(), emittedFiles = _a.emittedFiles, emitSkipped = _a.emitSkipped, emitDiagnostics = _a.diagnostics;
+        ts.addRange(diagnostics, emitDiagnostics);
+        if (reportSemanticDiagnostics) {
+            ts.addRange(diagnostics, program.getSemanticDiagnostics());
+        }
+        ts.sortAndDeduplicateDiagnostics(diagnostics).forEach(reportDiagnostic);
+        if (writeFileName) {
+            var currentDir_1 = program.getCurrentDirectory();
+            ts.forEach(emittedFiles, function (file) {
+                var filepath = ts.getNormalizedAbsolutePath(file, currentDir_1);
+                writeFileName("TSFILE: " + filepath);
+            });
+            if (program.getCompilerOptions().listFiles) {
+                ts.forEach(program.getSourceFiles(), function (file) {
+                    writeFileName(file.fileName);
+                });
+            }
+        }
+        if (reportSummary) {
+            reportSummary(diagnostics.filter(function (diagnostic) { return diagnostic.category === ts.DiagnosticCategory.Error; }).length);
+        }
+        if (emitSkipped && diagnostics.length > 0) {
+            // If the emitter didn't emit anything, then pass that value along.
+            return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
+        }
+        else if (diagnostics.length > 0) {
+            // The emitter emitted something, inform the caller if that happened in the presence
+            // of diagnostics or not.
+            return ts.ExitStatus.DiagnosticsPresent_OutputsGenerated;
+        }
+        return ts.ExitStatus.Success;
+    }
+    ts.emitFilesAndReportErrors = emitFilesAndReportErrors;
+    var noopFileWatcher = { close: ts.noop };
+    /**
+     * Creates the watch compiler host that can be extended with config file or root file names and options host
+     */
+    function createWatchCompilerHost(system, createProgram, reportDiagnostic, reportWatchStatus) {
+        if (system === void 0) { system = ts.sys; }
+        if (!createProgram) {
+            createProgram = ts.createEmitAndSemanticDiagnosticsBuilderProgram;
+        }
+        var host = system;
+        var useCaseSensitiveFileNames = function () { return system.useCaseSensitiveFileNames; };
+        var writeFileName = function (s) { return system.write(s + system.newLine); };
+        var onWatchStatusChange = reportWatchStatus || createWatchStatusReporter(system);
+        return {
+            useCaseSensitiveFileNames: useCaseSensitiveFileNames,
+            getNewLine: function () { return system.newLine; },
+            getCurrentDirectory: function () { return system.getCurrentDirectory(); },
+            getDefaultLibLocation: getDefaultLibLocation,
+            getDefaultLibFileName: function (options) { return ts.combinePaths(getDefaultLibLocation(), ts.getDefaultLibFileName(options)); },
+            fileExists: function (path) { return system.fileExists(path); },
+            readFile: function (path, encoding) { return system.readFile(path, encoding); },
+            directoryExists: function (path) { return system.directoryExists(path); },
+            getDirectories: function (path) { return system.getDirectories(path); },
+            readDirectory: function (path, extensions, exclude, include, depth) { return system.readDirectory(path, extensions, exclude, include, depth); },
+            realpath: system.realpath && (function (path) { return system.realpath(path); }),
+            getEnvironmentVariable: system.getEnvironmentVariable && (function (name) { return system.getEnvironmentVariable(name); }),
+            watchFile: system.watchFile ? (function (path, callback, pollingInterval) { return system.watchFile(path, callback, pollingInterval); }) : function () { return noopFileWatcher; },
+            watchDirectory: system.watchDirectory ? (function (path, callback, recursive) { return system.watchDirectory(path, callback, recursive); }) : function () { return noopFileWatcher; },
+            setTimeout: system.setTimeout ? (function (callback, ms) {
+                var args = [];
+                for (var _i = 2; _i < arguments.length; _i++) {
+                    args[_i - 2] = arguments[_i];
+                }
+                var _a;
+                return (_a = system.setTimeout).call.apply(_a, [system, callback, ms].concat(args));
+            }) : ts.noop,
+            clearTimeout: system.clearTimeout ? (function (timeoutId) { return system.clearTimeout(timeoutId); }) : ts.noop,
+            trace: function (s) { return system.write(s); },
+            onWatchStatusChange: onWatchStatusChange,
+            createDirectory: function (path) { return system.createDirectory(path); },
+            writeFile: function (path, data, writeByteOrderMark) { return system.writeFile(path, data, writeByteOrderMark); },
+            onCachedDirectoryStructureHostCreate: function (cacheHost) { return host = cacheHost || system; },
+            createHash: system.createHash && (function (s) { return system.createHash(s); }),
+            createProgram: createProgram,
+            afterProgramCreate: emitFilesAndReportErrorUsingBuilder
+        };
+        function getDefaultLibLocation() {
+            return ts.getDirectoryPath(ts.normalizePath(system.getExecutingFilePath()));
+        }
+        function emitFilesAndReportErrorUsingBuilder(builderProgram) {
+            var compilerOptions = builderProgram.getCompilerOptions();
+            var newLine = ts.getNewLineCharacter(compilerOptions, function () { return system.newLine; });
+            var reportSummary = function (errorCount) {
+                if (errorCount === 1) {
+                    onWatchStatusChange(ts.createCompilerDiagnostic(ts.Diagnostics.Found_1_error_Watching_for_file_changes, errorCount), newLine, compilerOptions);
+                }
+                else {
+                    onWatchStatusChange(ts.createCompilerDiagnostic(ts.Diagnostics.Found_0_errors_Watching_for_file_changes, errorCount, errorCount), newLine, compilerOptions);
+                }
+            };
+            emitFilesAndReportErrors(builderProgram, reportDiagnostic, writeFileName, reportSummary);
+        }
+    }
+    /**
+     * Report error and exit
+     */
+    function reportUnrecoverableDiagnostic(system, reportDiagnostic, diagnostic) {
+        reportDiagnostic(diagnostic);
+        system.exit(ts.ExitStatus.DiagnosticsPresent_OutputsSkipped);
+    }
+    /**
+     * Creates the watch compiler host from system for config file in watch mode
+     */
+    function createWatchCompilerHostOfConfigFile(configFileName, optionsToExtend, system, createProgram, reportDiagnostic, reportWatchStatus) {
+        var diagnosticReporter = reportDiagnostic || createDiagnosticReporter(system);
+        var host = createWatchCompilerHost(system, createProgram, diagnosticReporter, reportWatchStatus);
+        host.onUnRecoverableConfigFileDiagnostic = function (diagnostic) { return reportUnrecoverableDiagnostic(system, diagnosticReporter, diagnostic); };
+        host.configFileName = configFileName;
+        host.optionsToExtend = optionsToExtend;
+        return host;
+    }
+    ts.createWatchCompilerHostOfConfigFile = createWatchCompilerHostOfConfigFile;
+    /**
+     * Creates the watch compiler host from system for compiling root files and options in watch mode
+     */
+    function createWatchCompilerHostOfFilesAndCompilerOptions(rootFiles, options, system, createProgram, reportDiagnostic, reportWatchStatus) {
+        var host = createWatchCompilerHost(system, createProgram, reportDiagnostic || createDiagnosticReporter(system), reportWatchStatus);
+        host.rootFiles = rootFiles;
+        host.options = options;
+        return host;
+    }
+    ts.createWatchCompilerHostOfFilesAndCompilerOptions = createWatchCompilerHostOfFilesAndCompilerOptions;
+})(ts || (ts = {}));
+(function (ts) {
+    function createWatchCompilerHost(rootFilesOrConfigFileName, options, system, createProgram, reportDiagnostic, reportWatchStatus) {
+        if (ts.isArray(rootFilesOrConfigFileName)) {
+            return ts.createWatchCompilerHostOfFilesAndCompilerOptions(rootFilesOrConfigFileName, options, system, createProgram, reportDiagnostic, reportWatchStatus); // TODO: GH#18217
+        }
+        else {
+            return ts.createWatchCompilerHostOfConfigFile(rootFilesOrConfigFileName, options, system, createProgram, reportDiagnostic, reportWatchStatus);
+        }
+    }
+    ts.createWatchCompilerHost = createWatchCompilerHost;
+    var initialVersion = 1;
+    function createWatchProgram(host) {
+        var builderProgram;
+        var reloadLevel; // level to indicate if the program needs to be reloaded from config file/just filenames etc
+        var missingFilesMap; // Map of file watchers for the missing files
+        var watchedWildcardDirectories; // map of watchers for the wild card directories in the config file
+        var timerToUpdateProgram; // timer callback to recompile the program
+        var sourceFilesCache = ts.createMap(); // Cache that stores the source file and version info
+        var missingFilePathsRequestedForRelease; // These paths are held temparirly so that we can remove the entry from source file cache if the file is not tracked by missing files
+        var hasChangedCompilerOptions = false; // True if the compiler options have changed between compilations
+        var hasChangedAutomaticTypeDirectiveNames = false; // True if the automatic type directives have changed
+        var useCaseSensitiveFileNames = host.useCaseSensitiveFileNames();
+        var currentDirectory = host.getCurrentDirectory();
+        var getCurrentDirectory = function () { return currentDirectory; };
+        var readFile = function (path, encoding) { return host.readFile(path, encoding); };
+        var configFileName = host.configFileName, _a = host.optionsToExtend, optionsToExtendForConfigFile = _a === void 0 ? {} : _a, createProgram = host.createProgram;
+        var rootFileNames = host.rootFiles, compilerOptions = host.options;
+        var configFileSpecs;
+        var configFileParsingDiagnostics;
+        var hasChangedConfigFileParsingErrors = false;
+        var cachedDirectoryStructureHost = configFileName === undefined ? undefined : ts.createCachedDirectoryStructureHost(host, currentDirectory, useCaseSensitiveFileNames);
+        if (cachedDirectoryStructureHost && host.onCachedDirectoryStructureHostCreate) {
+            host.onCachedDirectoryStructureHostCreate(cachedDirectoryStructureHost);
+        }
+        var directoryStructureHost = cachedDirectoryStructureHost || host;
+        var parseConfigFileHost = {
+            useCaseSensitiveFileNames: useCaseSensitiveFileNames,
+            readDirectory: function (path, extensions, exclude, include, depth) { return directoryStructureHost.readDirectory(path, extensions, exclude, include, depth); },
+            fileExists: function (path) { return host.fileExists(path); },
+            readFile: readFile,
+            getCurrentDirectory: getCurrentDirectory,
+            onUnRecoverableConfigFileDiagnostic: host.onUnRecoverableConfigFileDiagnostic
+        };
+        // From tsc we want to get already parsed result and hence check for rootFileNames
+        var newLine = updateNewLine();
+        reportWatchDiagnostic(ts.Diagnostics.Starting_compilation_in_watch_mode);
+        if (configFileName) {
+            newLine = ts.getNewLineCharacter(optionsToExtendForConfigFile, function () { return host.getNewLine(); });
+            if (host.configFileParsingResult) {
+                setConfigFileParsingResult(host.configFileParsingResult);
+            }
+            else {
+                ts.Debug.assert(!rootFileNames);
+                parseConfigFile();
+            }
+            newLine = updateNewLine();
+        }
+        var trace = host.trace && (function (s) { host.trace(s + newLine); });
+        var watchLogLevel = trace ? compilerOptions.extendedDiagnostics ? ts.WatchLogLevel.Verbose :
+            compilerOptions.diagnostis ? ts.WatchLogLevel.TriggerOnly : ts.WatchLogLevel.None : ts.WatchLogLevel.None;
+        var writeLog = watchLogLevel !== ts.WatchLogLevel.None ? trace : ts.noop; // TODO: GH#18217
+        var _b = ts.getWatchFactory(watchLogLevel, writeLog), watchFile = _b.watchFile, watchFilePath = _b.watchFilePath, watchDirectory = _b.watchDirectory;
+        var getCanonicalFileName = ts.createGetCanonicalFileName(useCaseSensitiveFileNames);
+        writeLog("Current directory: " + currentDirectory + " CaseSensitiveFileNames: " + useCaseSensitiveFileNames);
+        if (configFileName) {
+            watchFile(host, configFileName, scheduleProgramReload, ts.PollingInterval.High, "Config file");
+        }
+        var compilerHost = {
+            // Members for CompilerHost
+            getSourceFile: function (fileName, languageVersion, onError, shouldCreateNewSourceFile) { return getVersionedSourceFileByPath(fileName, toPath(fileName), languageVersion, onError, shouldCreateNewSourceFile); },
+            getSourceFileByPath: getVersionedSourceFileByPath,
+            getDefaultLibLocation: host.getDefaultLibLocation && (function () { return host.getDefaultLibLocation(); }),
+            getDefaultLibFileName: function (options) { return host.getDefaultLibFileName(options); },
+            writeFile: writeFile,
+            getCurrentDirectory: getCurrentDirectory,
+            useCaseSensitiveFileNames: function () { return useCaseSensitiveFileNames; },
+            getCanonicalFileName: getCanonicalFileName,
+            getNewLine: function () { return newLine; },
+            fileExists: fileExists,
+            readFile: readFile,
+            trace: trace,
+            directoryExists: directoryStructureHost.directoryExists && (function (path) { return directoryStructureHost.directoryExists(path); }),
+            getDirectories: (directoryStructureHost.getDirectories && (function (path) { return directoryStructureHost.getDirectories(path); })),
+            realpath: host.realpath && (function (s) { return host.realpath(s); }),
+            getEnvironmentVariable: host.getEnvironmentVariable ? (function (name) { return host.getEnvironmentVariable(name); }) : (function () { return ""; }),
+            onReleaseOldSourceFile: onReleaseOldSourceFile,
+            createHash: host.createHash && (function (data) { return host.createHash(data); }),
+            // Members for ResolutionCacheHost
+            toPath: toPath,
+            getCompilationSettings: function () { return compilerOptions; },
+            watchDirectoryOfFailedLookupLocation: function (dir, cb, flags) { return watchDirectory(host, dir, cb, flags, "Failed Lookup Locations"); },
+            watchTypeRootsDirectory: function (dir, cb, flags) { return watchDirectory(host, dir, cb, flags, "Type roots"); },
+            getCachedDirectoryStructureHost: function () { return cachedDirectoryStructureHost; },
+            onInvalidatedResolution: scheduleProgramUpdate,
+            onChangedAutomaticTypeDirectiveNames: function () {
+                hasChangedAutomaticTypeDirectiveNames = true;
+                scheduleProgramUpdate();
+            },
+            maxNumberOfFilesToIterateForInvalidation: host.maxNumberOfFilesToIterateForInvalidation,
+            getCurrentProgram: getCurrentProgram,
+            writeLog: writeLog
+        };
+        // Cache for the module resolution
+        var resolutionCache = ts.createResolutionCache(compilerHost, configFileName ?
+            ts.getDirectoryPath(ts.getNormalizedAbsolutePath(configFileName, currentDirectory)) :
+            currentDirectory, 
+        /*logChangesWhenResolvingModule*/ false);
+        // Resolve module using host module resolution strategy if provided otherwise use resolution cache to resolve module names
+        compilerHost.resolveModuleNames = host.resolveModuleNames ?
+            (function (moduleNames, containingFile, reusedNames) { return host.resolveModuleNames(moduleNames, containingFile, reusedNames); }) :
+            (function (moduleNames, containingFile, reusedNames) { return resolutionCache.resolveModuleNames(moduleNames, containingFile, reusedNames); });
+        compilerHost.resolveTypeReferenceDirectives = host.resolveTypeReferenceDirectives ?
+            (function (typeDirectiveNames, containingFile) { return host.resolveTypeReferenceDirectives(typeDirectiveNames, containingFile); }) :
+            (function (typeDirectiveNames, containingFile) { return resolutionCache.resolveTypeReferenceDirectives(typeDirectiveNames, containingFile); });
+        var userProvidedResolution = !!host.resolveModuleNames || !!host.resolveTypeReferenceDirectives;
+        synchronizeProgram();
+        // Update the wild card directory watch
+        watchConfigFileWildCardDirectories();
+        return configFileName ?
+            { getCurrentProgram: getCurrentBuilderProgram, getProgram: synchronizeProgram } :
+            { getCurrentProgram: getCurrentBuilderProgram, getProgram: synchronizeProgram, updateRootFileNames: updateRootFileNames };
+        function getCurrentBuilderProgram() {
+            return builderProgram;
+        }
+        function getCurrentProgram() {
+            return builderProgram && builderProgram.getProgram();
+        }
+        function synchronizeProgram() {
+            writeLog("Synchronizing program");
+            var program = getCurrentProgram();
+            if (hasChangedCompilerOptions) {
+                newLine = updateNewLine();
+                if (program && ts.changesAffectModuleResolution(program.getCompilerOptions(), compilerOptions)) {
+                    resolutionCache.clear();
+                }
+            }
+            // All resolutions are invalid if user provided resolutions
+            var hasInvalidatedResolution = resolutionCache.createHasInvalidatedResolution(userProvidedResolution);
+            if (ts.isProgramUptoDate(getCurrentProgram(), rootFileNames, compilerOptions, getSourceVersion, fileExists, hasInvalidatedResolution, hasChangedAutomaticTypeDirectiveNames)) {
+                if (hasChangedConfigFileParsingErrors) {
+                    builderProgram = createProgram(/*rootNames*/ undefined, /*options*/ undefined, compilerHost, builderProgram, configFileParsingDiagnostics);
+                    hasChangedConfigFileParsingErrors = false;
+                }
+            }
+            else {
+                createNewProgram(program, hasInvalidatedResolution);
+            }
+            if (host.afterProgramCreate) {
+                host.afterProgramCreate(builderProgram);
+            }
+            return builderProgram;
+        }
+        function createNewProgram(program, hasInvalidatedResolution) {
+            // Compile the program
+            if (watchLogLevel !== ts.WatchLogLevel.None) {
+                writeLog("CreatingProgramWith::");
+                writeLog("  roots: " + JSON.stringify(rootFileNames));
+                writeLog("  options: " + JSON.stringify(compilerOptions));
+            }
+            var needsUpdateInTypeRootWatch = hasChangedCompilerOptions || !program;
+            hasChangedCompilerOptions = false;
+            hasChangedConfigFileParsingErrors = false;
+            resolutionCache.startCachingPerDirectoryResolution();
+            compilerHost.hasInvalidatedResolution = hasInvalidatedResolution;
+            compilerHost.hasChangedAutomaticTypeDirectiveNames = hasChangedAutomaticTypeDirectiveNames;
+            builderProgram = createProgram(rootFileNames, compilerOptions, compilerHost, builderProgram, configFileParsingDiagnostics);
+            resolutionCache.finishCachingPerDirectoryResolution();
+            // Update watches
+            ts.updateMissingFilePathsWatch(builderProgram.getProgram(), missingFilesMap || (missingFilesMap = ts.createMap()), watchMissingFilePath);
+            if (needsUpdateInTypeRootWatch) {
+                resolutionCache.updateTypeRootsWatch();
+            }
+            if (missingFilePathsRequestedForRelease) {
+                // These are the paths that program creater told us as not in use any more but were missing on the disk.
+                // We didnt remove the entry for them from sourceFiles cache so that we dont have to do File IO,
+                // if there is already watcher for it (for missing files)
+                // At this point our watches were updated, hence now we know that these paths are not tracked and need to be removed
+                // so that at later time we have correct result of their presence
+                for (var _i = 0, missingFilePathsRequestedForRelease_1 = missingFilePathsRequestedForRelease; _i < missingFilePathsRequestedForRelease_1.length; _i++) {
+                    var missingFilePath = missingFilePathsRequestedForRelease_1[_i];
+                    if (!missingFilesMap.has(missingFilePath)) {
+                        sourceFilesCache.delete(missingFilePath);
+                    }
+                }
+                missingFilePathsRequestedForRelease = undefined;
+            }
+        }
+        function updateRootFileNames(files) {
+            ts.Debug.assert(!configFileName, "Cannot update root file names with config file watch mode");
+            rootFileNames = files;
+            scheduleProgramUpdate();
+        }
+        function updateNewLine() {
+            return ts.getNewLineCharacter(compilerOptions || optionsToExtendForConfigFile, function () { return host.getNewLine(); });
+        }
+        function toPath(fileName) {
+            return ts.toPath(fileName, currentDirectory, getCanonicalFileName);
+        }
+        function isFileMissingOnHost(hostSourceFile) {
+            return typeof hostSourceFile === "number";
+        }
+        function isFilePresentOnHost(hostSourceFile) {
+            return !!hostSourceFile.sourceFile;
+        }
+        function fileExists(fileName) {
+            var path = toPath(fileName);
+            // If file is missing on host from cache, we can definitely say file doesnt exist
+            // otherwise we need to ensure from the disk
+            if (isFileMissingOnHost(sourceFilesCache.get(path))) {
+                return true;
+            }
+            return directoryStructureHost.fileExists(fileName);
+        }
+        function getVersionedSourceFileByPath(fileName, path, languageVersion, onError, shouldCreateNewSourceFile) {
+            var hostSourceFile = sourceFilesCache.get(path);
+            // No source file on the host
+            if (isFileMissingOnHost(hostSourceFile)) {
+                return undefined;
+            }
+            // Create new source file if requested or the versions dont match
+            if (!hostSourceFile || shouldCreateNewSourceFile || !isFilePresentOnHost(hostSourceFile) || hostSourceFile.version.toString() !== hostSourceFile.sourceFile.version) {
+                var sourceFile = getNewSourceFile();
+                if (hostSourceFile) {
+                    if (shouldCreateNewSourceFile) {
+                        hostSourceFile.version++;
+                    }
+                    if (sourceFile) {
+                        // Set the source file and create file watcher now that file was present on the disk
+                        hostSourceFile.sourceFile = sourceFile;
+                        sourceFile.version = hostSourceFile.version.toString();
+                        if (!hostSourceFile.fileWatcher) {
+                            hostSourceFile.fileWatcher = watchFilePath(host, fileName, onSourceFileChange, ts.PollingInterval.Low, path, "Source file");
+                        }
+                    }
+                    else {
+                        // There is no source file on host any more, close the watch, missing file paths will track it
+                        if (isFilePresentOnHost(hostSourceFile)) {
+                            hostSourceFile.fileWatcher.close();
+                        }
+                        sourceFilesCache.set(path, hostSourceFile.version);
+                    }
+                }
+                else {
+                    if (sourceFile) {
+                        sourceFile.version = initialVersion.toString();
+                        var fileWatcher = watchFilePath(host, fileName, onSourceFileChange, ts.PollingInterval.Low, path, "Source file");
+                        sourceFilesCache.set(path, { sourceFile: sourceFile, version: initialVersion, fileWatcher: fileWatcher });
+                    }
+                    else {
+                        sourceFilesCache.set(path, initialVersion);
+                    }
+                }
+                return sourceFile;
+            }
+            return hostSourceFile.sourceFile;
+            function getNewSourceFile() {
+                var text;
+                try {
+                    ts.performance.mark("beforeIORead");
+                    text = host.readFile(fileName, compilerOptions.charset);
+                    ts.performance.mark("afterIORead");
+                    ts.performance.measure("I/O Read", "beforeIORead", "afterIORead");
+                }
+                catch (e) {
+                    if (onError) {
+                        onError(e.message);
+                    }
+                }
+                return text !== undefined ? ts.createSourceFile(fileName, text, languageVersion) : undefined;
+            }
+        }
+        function nextSourceFileVersion(path) {
+            var hostSourceFile = sourceFilesCache.get(path);
+            if (hostSourceFile !== undefined) {
+                if (isFileMissingOnHost(hostSourceFile)) {
+                    // The next version, lets set it as presence unknown file
+                    sourceFilesCache.set(path, { version: Number(hostSourceFile) + 1 });
+                }
+                else {
+                    hostSourceFile.version++;
+                }
+            }
+        }
+        function getSourceVersion(path) {
+            var hostSourceFile = sourceFilesCache.get(path);
+            return !hostSourceFile || isFileMissingOnHost(hostSourceFile) ? undefined : hostSourceFile.version.toString();
+        }
+        function onReleaseOldSourceFile(oldSourceFile, _oldOptions) {
+            var hostSourceFileInfo = sourceFilesCache.get(oldSourceFile.path);
+            // If this is the source file thats in the cache and new program doesnt need it,
+            // remove the cached entry.
+            // Note we arent deleting entry if file became missing in new program or
+            // there was version update and new source file was created.
+            if (hostSourceFileInfo) {
+                // record the missing file paths so they can be removed later if watchers arent tracking them
+                if (isFileMissingOnHost(hostSourceFileInfo)) {
+                    (missingFilePathsRequestedForRelease || (missingFilePathsRequestedForRelease = [])).push(oldSourceFile.path);
+                }
+                else if (hostSourceFileInfo.sourceFile === oldSourceFile) {
+                    if (hostSourceFileInfo.fileWatcher) {
+                        hostSourceFileInfo.fileWatcher.close();
+                    }
+                    sourceFilesCache.delete(oldSourceFile.path);
+                    resolutionCache.removeResolutionsOfFile(oldSourceFile.path);
+                }
+            }
+        }
+        function reportWatchDiagnostic(message) {
+            if (host.onWatchStatusChange) {
+                host.onWatchStatusChange(ts.createCompilerDiagnostic(message), newLine, compilerOptions || optionsToExtendForConfigFile);
+            }
+        }
+        // Upon detecting a file change, wait for 250ms and then perform a recompilation. This gives batch
+        // operations (such as saving all modified files in an editor) a chance to complete before we kick
+        // off a new compilation.
+        function scheduleProgramUpdate() {
+            if (!host.setTimeout || !host.clearTimeout) {
+                return;
+            }
+            if (timerToUpdateProgram) {
+                host.clearTimeout(timerToUpdateProgram);
+            }
+            writeLog("Scheduling update");
+            timerToUpdateProgram = host.setTimeout(updateProgram, 250);
+        }
+        function scheduleProgramReload() {
+            ts.Debug.assert(!!configFileName);
+            reloadLevel = ts.ConfigFileProgramReloadLevel.Full;
+            scheduleProgramUpdate();
+        }
+        function updateProgram() {
+            timerToUpdateProgram = undefined;
+            reportWatchDiagnostic(ts.Diagnostics.File_change_detected_Starting_incremental_compilation);
+            switch (reloadLevel) {
+                case ts.ConfigFileProgramReloadLevel.Partial:
+                    return reloadFileNamesFromConfigFile();
+                case ts.ConfigFileProgramReloadLevel.Full:
+                    return reloadConfigFile();
+                default:
+                    synchronizeProgram();
+                    return;
+            }
+        }
+        function reloadFileNamesFromConfigFile() {
+            writeLog("Reloading new file names and options");
+            var result = ts.getFileNamesFromConfigSpecs(configFileSpecs, ts.getDirectoryPath(configFileName), compilerOptions, parseConfigFileHost);
+            if (result.fileNames.length) {
+                configFileParsingDiagnostics = ts.filter(configFileParsingDiagnostics, function (error) { return !ts.isErrorNoInputFiles(error); });
+                hasChangedConfigFileParsingErrors = true;
+            }
+            else if (!configFileSpecs.filesSpecs && !ts.some(configFileParsingDiagnostics, ts.isErrorNoInputFiles)) {
+                configFileParsingDiagnostics = configFileParsingDiagnostics.concat(ts.getErrorForNoInputFiles(configFileSpecs, configFileName));
+                hasChangedConfigFileParsingErrors = true;
+            }
+            rootFileNames = result.fileNames;
+            // Update the program
+            synchronizeProgram();
+        }
+        function reloadConfigFile() {
+            writeLog("Reloading config file: " + configFileName);
+            reloadLevel = ts.ConfigFileProgramReloadLevel.None;
+            if (cachedDirectoryStructureHost) {
+                cachedDirectoryStructureHost.clearCache();
+            }
+            parseConfigFile();
+            hasChangedCompilerOptions = true;
+            synchronizeProgram();
+            // Update the wild card directory watch
+            watchConfigFileWildCardDirectories();
+        }
+        function parseConfigFile() {
+            setConfigFileParsingResult(ts.getParsedCommandLineOfConfigFile(configFileName, optionsToExtendForConfigFile, parseConfigFileHost)); // TODO: GH#18217
+        }
+        function setConfigFileParsingResult(configFileParseResult) {
+            rootFileNames = configFileParseResult.fileNames;
+            compilerOptions = configFileParseResult.options;
+            configFileSpecs = configFileParseResult.configFileSpecs; // TODO: GH#18217
+            configFileParsingDiagnostics = ts.getConfigFileParsingDiagnostics(configFileParseResult);
+            hasChangedConfigFileParsingErrors = true;
+        }
+        function onSourceFileChange(fileName, eventKind, path) {
+            updateCachedSystemWithFile(fileName, path, eventKind);
+            // Update the source file cache
+            if (eventKind === ts.FileWatcherEventKind.Deleted && sourceFilesCache.get(path)) {
+                resolutionCache.invalidateResolutionOfFile(path);
+            }
+            nextSourceFileVersion(path);
+            // Update the program
+            scheduleProgramUpdate();
+        }
+        function updateCachedSystemWithFile(fileName, path, eventKind) {
+            if (cachedDirectoryStructureHost) {
+                cachedDirectoryStructureHost.addOrDeleteFile(fileName, path, eventKind);
+            }
+        }
+        function watchMissingFilePath(missingFilePath) {
+            return watchFilePath(host, missingFilePath, onMissingFileChange, ts.PollingInterval.Medium, missingFilePath, "Missing file");
+        }
+        function onMissingFileChange(fileName, eventKind, missingFilePath) {
+            updateCachedSystemWithFile(fileName, missingFilePath, eventKind);
+            if (eventKind === ts.FileWatcherEventKind.Created && missingFilesMap.has(missingFilePath)) {
+                missingFilesMap.get(missingFilePath).close();
+                missingFilesMap.delete(missingFilePath);
+                // Delete the entry in the source files cache so that new source file is created
+                nextSourceFileVersion(missingFilePath);
+                // When a missing file is created, we should update the graph.
+                scheduleProgramUpdate();
+            }
+        }
+        function watchConfigFileWildCardDirectories() {
+            if (configFileSpecs) {
+                ts.updateWatchingWildcardDirectories(watchedWildcardDirectories || (watchedWildcardDirectories = ts.createMap()), ts.createMapFromTemplate(configFileSpecs.wildcardDirectories), watchWildcardDirectory);
+            }
+            else if (watchedWildcardDirectories) {
+                ts.clearMap(watchedWildcardDirectories, ts.closeFileWatcherOf);
+            }
+        }
+        function watchWildcardDirectory(directory, flags) {
+            return watchDirectory(host, directory, function (fileOrDirectory) {
+                ts.Debug.assert(!!configFileName);
+                var fileOrDirectoryPath = toPath(fileOrDirectory);
+                // Since the file existance changed, update the sourceFiles cache
+                if (cachedDirectoryStructureHost) {
+                    cachedDirectoryStructureHost.addOrDeleteFileOrDirectory(fileOrDirectory, fileOrDirectoryPath);
+                }
+                nextSourceFileVersion(fileOrDirectoryPath);
+                // If the the added or created file or directory is not supported file name, ignore the file
+                // But when watched directory is added/removed, we need to reload the file list
+                if (fileOrDirectoryPath !== directory && ts.hasExtension(fileOrDirectoryPath) && !ts.isSupportedSourceFileName(fileOrDirectory, compilerOptions)) {
+                    writeLog("Project: " + configFileName + " Detected file add/remove of non supported extension: " + fileOrDirectory);
+                    return;
+                }
+                // Reload is pending, do the reload
+                if (reloadLevel !== ts.ConfigFileProgramReloadLevel.Full) {
+                    reloadLevel = ts.ConfigFileProgramReloadLevel.Partial;
+                    // Schedule Update the program
+                    scheduleProgramUpdate();
+                }
+            }, flags, "Wild card directories");
+        }
+        function ensureDirectoriesExist(directoryPath) {
+            if (directoryPath.length > ts.getRootLength(directoryPath) && !host.directoryExists(directoryPath)) {
+                var parentDirectory = ts.getDirectoryPath(directoryPath);
+                ensureDirectoriesExist(parentDirectory);
+                host.createDirectory(directoryPath);
+            }
+        }
+        function writeFile(fileName, text, writeByteOrderMark, onError) {
+            try {
+                ts.performance.mark("beforeIOWrite");
+                ensureDirectoriesExist(ts.getDirectoryPath(ts.normalizePath(fileName)));
+                host.writeFile(fileName, text, writeByteOrderMark);
+                ts.performance.mark("afterIOWrite");
+                ts.performance.measure("I/O Write", "beforeIOWrite", "afterIOWrite");
+            }
+            catch (e) {
+                if (onError) {
+                    onError(e.message);
+                }
+            }
+        }
+    }
+    ts.createWatchProgram = createWatchProgram;
+})(ts || (ts = {}));
+var ts;
+(function (ts) {
+    var minimumDate = new Date(-8640000000000000);
+    var maximumDate = new Date(8640000000000000);
+    var BuildResultFlags;
+    (function (BuildResultFlags) {
+        BuildResultFlags[BuildResultFlags["None"] = 0] = "None";
+        /**
+         * No errors of any kind occurred during build
+         */
+        BuildResultFlags[BuildResultFlags["Success"] = 1] = "Success";
+        /**
+         * None of the .d.ts files emitted by this build were
+         * different from the existing files on disk
+         */
+        BuildResultFlags[BuildResultFlags["DeclarationOutputUnchanged"] = 2] = "DeclarationOutputUnchanged";
+        BuildResultFlags[BuildResultFlags["ConfigFileErrors"] = 4] = "ConfigFileErrors";
+        BuildResultFlags[BuildResultFlags["SyntaxErrors"] = 8] = "SyntaxErrors";
+        BuildResultFlags[BuildResultFlags["TypeErrors"] = 16] = "TypeErrors";
+        BuildResultFlags[BuildResultFlags["DeclarationEmitErrors"] = 32] = "DeclarationEmitErrors";
+        BuildResultFlags[BuildResultFlags["AnyErrors"] = 60] = "AnyErrors";
+    })(BuildResultFlags || (BuildResultFlags = {}));
+    var UpToDateStatusType;
+    (function (UpToDateStatusType) {
+        UpToDateStatusType[UpToDateStatusType["Unbuildable"] = 0] = "Unbuildable";
+        UpToDateStatusType[UpToDateStatusType["UpToDate"] = 1] = "UpToDate";
+        /**
+         * The project appears out of date because its upstream inputs are newer than its outputs,
+         * but all of its outputs are actually newer than the previous identical outputs of its (.d.ts) inputs.
+         * This means we can Pseudo-build (just touch timestamps), as if we had actually built this project.
+         */
+        UpToDateStatusType[UpToDateStatusType["UpToDateWithUpstreamTypes"] = 2] = "UpToDateWithUpstreamTypes";
+        UpToDateStatusType[UpToDateStatusType["OutputMissing"] = 3] = "OutputMissing";
+        UpToDateStatusType[UpToDateStatusType["OutOfDateWithSelf"] = 4] = "OutOfDateWithSelf";
+        UpToDateStatusType[UpToDateStatusType["OutOfDateWithUpstream"] = 5] = "OutOfDateWithUpstream";
+        UpToDateStatusType[UpToDateStatusType["UpstreamOutOfDate"] = 6] = "UpstreamOutOfDate";
+        UpToDateStatusType[UpToDateStatusType["UpstreamBlocked"] = 7] = "UpstreamBlocked";
+        /**
+         * Projects with no outputs (i.e. "solution" files)
+         */
+        UpToDateStatusType[UpToDateStatusType["ContainerOnly"] = 8] = "ContainerOnly";
+    })(UpToDateStatusType = ts.UpToDateStatusType || (ts.UpToDateStatusType = {}));
+    /**
+     * A FileMap maintains a normalized-key to value relationship
+     */
+    function createFileMap() {
+        // tslint:disable-next-line:no-null-keyword
+        var lookup = ts.createMap();
+        return {
+            setValue: setValue,
+            getValue: getValue,
+            getValueOrUndefined: getValueOrUndefined,
+            removeKey: removeKey,
+            getKeys: getKeys,
+            hasKey: hasKey
+        };
+        function getKeys() {
+            return Object.keys(lookup);
+        }
+        function hasKey(fileName) {
+            return lookup.has(ts.normalizePath(fileName));
+        }
+        function removeKey(fileName) {
+            lookup.delete(ts.normalizePath(fileName));
+        }
+        function setValue(fileName, value) {
+            lookup.set(ts.normalizePath(fileName), value);
+        }
+        function getValue(fileName) {
+            var f = ts.normalizePath(fileName);
+            if (lookup.has(f)) {
+                return lookup.get(f);
+            }
+            else {
+                throw new Error("No value corresponding to " + fileName + " exists in this map");
+            }
+        }
+        function getValueOrUndefined(fileName) {
+            var f = ts.normalizePath(fileName);
+            return lookup.get(f);
+        }
+    }
+    function createDependencyMapper() {
+        var childToParents = createFileMap();
+        var parentToChildren = createFileMap();
+        var allKeys = createFileMap();
+        function addReference(childConfigFileName, parentConfigFileName) {
+            addEntry(childToParents, childConfigFileName, parentConfigFileName);
+            addEntry(parentToChildren, parentConfigFileName, childConfigFileName);
+        }
+        function getReferencesTo(parentConfigFileName) {
+            return parentToChildren.getValueOrUndefined(parentConfigFileName) || [];
+        }
+        function getReferencesOf(childConfigFileName) {
+            return childToParents.getValueOrUndefined(childConfigFileName) || [];
+        }
+        function getKeys() {
+            return allKeys.getKeys();
+        }
+        function addEntry(mapToAddTo, key, element) {
+            key = ts.normalizePath(key);
+            element = ts.normalizePath(element);
+            var arr = mapToAddTo.getValueOrUndefined(key);
+            if (arr === undefined) {
+                mapToAddTo.setValue(key, arr = []);
+            }
+            if (arr.indexOf(element) < 0) {
+                arr.push(element);
+            }
+            allKeys.setValue(key, true);
+            allKeys.setValue(element, true);
+        }
+        return {
+            addReference: addReference,
+            getReferencesTo: getReferencesTo,
+            getReferencesOf: getReferencesOf,
+            getKeys: getKeys
+        };
+    }
+    function getOutputDeclarationFileName(inputFileName, configFile) {
+        var relativePath = ts.getRelativePathFromDirectory(rootDirOfOptions(configFile.options, configFile.options.configFilePath), inputFileName, /*ignoreCase*/ true);
+        var outputPath = ts.resolvePath(configFile.options.declarationDir || configFile.options.outDir || ts.getDirectoryPath(configFile.options.configFilePath), relativePath);
+        return ts.changeExtension(outputPath, ".d.ts" /* Dts */);
+    }
+    function getOutputJavaScriptFileName(inputFileName, configFile) {
+        var relativePath = ts.getRelativePathFromDirectory(rootDirOfOptions(configFile.options, configFile.options.configFilePath), inputFileName, /*ignoreCase*/ true);
+        var outputPath = ts.resolvePath(configFile.options.outDir || ts.getDirectoryPath(configFile.options.configFilePath), relativePath);
+        return ts.changeExtension(outputPath, (ts.fileExtensionIs(inputFileName, ".tsx" /* Tsx */) && configFile.options.jsx === 1 /* Preserve */) ? ".jsx" /* Jsx */ : ".js" /* Js */);
+    }
+    function getOutputFileNames(inputFileName, configFile) {
+        if (configFile.options.outFile) {
+            return ts.emptyArray;
+        }
+        var outputs = [];
+        outputs.push(getOutputJavaScriptFileName(inputFileName, configFile));
+        if (configFile.options.declaration) {
+            var dts = outputs.push(getOutputDeclarationFileName(inputFileName, configFile));
+            if (configFile.options.declarationMap) {
+                outputs.push(dts + ".map");
+            }
+        }
+        return outputs;
+    }
+    function getOutFileOutputs(project) {
+        if (!project.options.outFile) {
+            return ts.Debug.fail("outFile must be set");
+        }
+        var outputs = [];
+        outputs.push(project.options.outFile);
+        if (project.options.declaration) {
+            var dts = ts.changeExtension(project.options.outFile, ".d.ts" /* Dts */);
+            outputs.push(dts);
+            if (project.options.declarationMap) {
+                outputs.push(dts + ".map");
+            }
+        }
+        return outputs;
+    }
+    function rootDirOfOptions(opts, configFileName) {
+        return opts.rootDir || ts.getDirectoryPath(configFileName);
+    }
+    function createConfigFileCache(host) {
+        var cache = createFileMap();
+        var configParseHost = ts.parseConfigHostFromCompilerHost(host);
+        function parseConfigFile(configFilePath) {
+            var sourceFile = host.getSourceFile(configFilePath, 100 /* JSON */);
+            if (sourceFile === undefined) {
+                return undefined;
+            }
+            var parsed = ts.parseJsonSourceFileConfigFileContent(sourceFile, configParseHost, ts.getDirectoryPath(configFilePath));
+            parsed.options.configFilePath = configFilePath;
+            cache.setValue(configFilePath, parsed);
+            return parsed;
+        }
+        function removeKey(configFilePath) {
+            cache.removeKey(configFilePath);
+        }
+        return {
+            parseConfigFile: parseConfigFile,
+            removeKey: removeKey
+        };
+    }
+    function newer(date1, date2) {
+        return date2 > date1 ? date2 : date1;
+    }
+    function isDeclarationFile(fileName) {
+        return ts.fileExtensionIs(fileName, ".d.ts" /* Dts */);
+    }
+    function createBuildContext(options) {
+        var invalidatedProjects = createFileMap();
+        var queuedProjects = createFileMap();
+        var missingRoots = ts.createMap();
+        return {
+            options: options,
+            projectStatus: createFileMap(),
+            unchangedOutputs: createFileMap(),
+            invalidatedProjects: invalidatedProjects,
+            missingRoots: missingRoots,
+            queuedProjects: queuedProjects
+        };
+    }
+    ts.createBuildContext = createBuildContext;
+    var buildOpts = [
+        {
+            name: "verbose",
+            shortName: "v",
+            category: ts.Diagnostics.Command_line_Options,
+            description: ts.Diagnostics.Enable_verbose_logging,
+            type: "boolean"
+        },
+        {
+            name: "dry",
+            shortName: "d",
+            category: ts.Diagnostics.Command_line_Options,
+            description: ts.Diagnostics.Show_what_would_be_built_or_deleted_if_specified_with_clean,
+            type: "boolean"
+        },
+        {
+            name: "force",
+            shortName: "f",
+            category: ts.Diagnostics.Command_line_Options,
+            description: ts.Diagnostics.Build_all_projects_including_those_that_appear_to_be_up_to_date,
+            type: "boolean"
+        },
+        {
+            name: "clean",
+            category: ts.Diagnostics.Command_line_Options,
+            description: ts.Diagnostics.Delete_the_outputs_of_all_projects,
+            type: "boolean"
+        },
+        {
+            name: "watch",
+            category: ts.Diagnostics.Command_line_Options,
+            description: ts.Diagnostics.Watch_input_files,
+            type: "boolean"
+        }
+    ];
+    function performBuild(args, compilerHost, buildHost, system) {
+        var verbose = false;
+        var dry = false;
+        var force = false;
+        var clean = false;
+        var watch = false;
+        var projects = [];
+        for (var _i = 0, args_6 = args; _i < args_6.length; _i++) {
+            var arg = args_6[_i];
+            switch (arg.toLowerCase()) {
+                case "-v":
+                case "--verbose":
+                    verbose = true;
+                    continue;
+                case "-d":
+                case "--dry":
+                    dry = true;
+                    continue;
+                case "-f":
+                case "--force":
+                    force = true;
+                    continue;
+                case "--clean":
+                    clean = true;
+                    continue;
+                case "--watch":
+                case "-w":
+                    watch = true;
+                    continue;
+                case "--?":
+                case "-?":
+                case "--help":
+                    ts.printHelp(buildOpts, "--build ");
+                    return ts.ExitStatus.Success;
+            }
+            // Not a flag, parse as filename
+            addProject(arg);
+        }
+        // Nonsensical combinations
+        if (clean && force) {
+            buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "force");
+            return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
+        }
+        if (clean && verbose) {
+            buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "verbose");
+            return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
+        }
+        if (clean && watch) {
+            buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "clean", "watch");
+            return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
+        }
+        if (watch && dry) {
+            buildHost.error(ts.Diagnostics.Options_0_and_1_cannot_be_combined, "watch", "dry");
+            return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
+        }
+        if (projects.length === 0) {
+            // tsc -b invoked with no extra arguments; act as if invoked with "tsc -b ."
+            addProject(".");
+        }
+        var builder = createSolutionBuilder(compilerHost, buildHost, projects, { dry: dry, force: force, verbose: verbose }, system);
+        if (clean) {
+            return builder.cleanAllProjects();
+        }
+        if (watch) {
+            builder.startWatching();
+            return undefined;
+        }
+        return builder.buildAllProjects();
+        function addProject(projectSpecification) {
+            var fileName = ts.resolvePath(compilerHost.getCurrentDirectory(), projectSpecification);
+            var refPath = ts.resolveProjectReferencePath(compilerHost, { path: fileName });
+            if (!refPath) {
+                return buildHost.error(ts.Diagnostics.File_0_does_not_exist, projectSpecification);
+            }
+            if (!compilerHost.fileExists(refPath)) {
+                return buildHost.error(ts.Diagnostics.File_0_does_not_exist, fileName);
+            }
+            projects.push(refPath);
+        }
+    }
+    ts.performBuild = performBuild;
+    /**
+     * A SolutionBuilder has an immutable set of rootNames that are the "entry point" projects, but
+     * can dynamically add/remove other projects based on changes on the rootNames' references
+     */
+    function createSolutionBuilder(compilerHost, buildHost, rootNames, defaultOptions, system) {
+        if (!compilerHost.getModifiedTime || !compilerHost.setModifiedTime) {
+            throw new Error("Host must support timestamp APIs");
+        }
+        var configFileCache = createConfigFileCache(compilerHost);
+        var context = createBuildContext(defaultOptions);
+        var existingWatchersForWildcards = ts.createMap();
+        return {
+            buildAllProjects: buildAllProjects,
+            getUpToDateStatus: getUpToDateStatus,
+            getUpToDateStatusOfFile: getUpToDateStatusOfFile,
+            cleanAllProjects: cleanAllProjects,
+            resetBuildContext: resetBuildContext,
+            getBuildGraph: getBuildGraph,
+            invalidateProject: invalidateProject,
+            buildInvalidatedProjects: buildInvalidatedProjects,
+            buildDependentInvalidatedProjects: buildDependentInvalidatedProjects,
+            resolveProjectName: resolveProjectName,
+            startWatching: startWatching
+        };
+        function startWatching() {
+            if (!system)
+                throw new Error("System host must be provided if using --watch");
+            if (!system.watchFile || !system.watchDirectory || !system.setTimeout)
+                throw new Error("System host must support watchFile / watchDirectory / setTimeout if using --watch");
+            var graph = getGlobalDependencyGraph();
+            if (!graph.buildQueue) {
+                // Everything is broken - we don't even know what to watch. Give up.
+                return;
+            }
+            var _loop_12 = function (resolved) {
+                var cfg = configFileCache.parseConfigFile(resolved);
+                if (cfg) {
+                    // Watch this file
+                    system.watchFile(resolved, function () {
+                        configFileCache.removeKey(resolved);
+                        invalidateProjectAndScheduleBuilds(resolved);
+                    });
+                    // Update watchers for wildcard directories
+                    if (cfg.configFileSpecs) {
+                        ts.updateWatchingWildcardDirectories(existingWatchersForWildcards, ts.createMapFromTemplate(cfg.configFileSpecs.wildcardDirectories), function (dir, flags) {
+                            return system.watchDirectory(dir, function () {
+                                invalidateProjectAndScheduleBuilds(resolved);
+                            }, !!(flags & 1 /* Recursive */));
+                        });
+                    }
+                    // Watch input files
+                    for (var _i = 0, _a = cfg.fileNames; _i < _a.length; _i++) {
+                        var input = _a[_i];
+                        system.watchFile(input, function () {
+                            invalidateProjectAndScheduleBuilds(resolved);
+                        });
+                    }
+                }
+            };
+            for (var _i = 0, _a = graph.buildQueue; _i < _a.length; _i++) {
+                var resolved = _a[_i];
+                _loop_12(resolved);
+            }
+            function invalidateProjectAndScheduleBuilds(resolved) {
+                invalidateProject(resolved);
+                system.setTimeout(buildInvalidatedProjects, 100);
+                system.setTimeout(buildDependentInvalidatedProjects, 3000);
+            }
+        }
+        function resetBuildContext(opts) {
+            if (opts === void 0) { opts = defaultOptions; }
+            context = createBuildContext(opts);
+        }
+        function getUpToDateStatusOfFile(configFileName) {
+            return getUpToDateStatus(configFileCache.parseConfigFile(configFileName));
+        }
+        function getBuildGraph(configFileNames) {
+            var resolvedNames = resolveProjectNames(configFileNames);
+            if (resolvedNames === undefined)
+                return undefined;
+            return createDependencyGraph(resolvedNames);
+        }
+        function getGlobalDependencyGraph() {
+            return getBuildGraph(rootNames);
+        }
+        function getUpToDateStatus(project) {
+            if (project === undefined) {
+                return { type: UpToDateStatusType.Unbuildable, reason: "File deleted mid-build" };
+            }
+            var prior = context.projectStatus.getValueOrUndefined(project.options.configFilePath);
+            if (prior !== undefined) {
+                return prior;
+            }
+            var actual = getUpToDateStatusWorker(project);
+            context.projectStatus.setValue(project.options.configFilePath, actual);
+            return actual;
+        }
+        function invalidateProject(configFileName) {
+            var resolved = resolveProjectName(configFileName);
+            if (resolved === undefined) {
+                // If this was a rootName, we need to track it as missing.
+                // Otherwise we can just ignore it and have it possibly surface as an error in any downstream projects,
+                // if they exist
+                // TODO: do those things
+                return;
+            }
+            configFileCache.removeKey(resolved);
+            context.invalidatedProjects.setValue(resolved, true);
+            context.projectStatus.removeKey(resolved);
+            var graph = getGlobalDependencyGraph();
+            if (graph) {
+                queueBuildForDownstreamReferences(resolved);
+            }
+            // Mark all downstream projects of this one needing to be built "later"
+            function queueBuildForDownstreamReferences(root) {
+                debugger;
+                var deps = graph.dependencyMap.getReferencesTo(root);
+                for (var _i = 0, deps_1 = deps; _i < deps_1.length; _i++) {
+                    var ref = deps_1[_i];
+                    // Can skip circular references
+                    if (!context.queuedProjects.hasKey(ref)) {
+                        context.queuedProjects.setValue(ref, true);
+                        queueBuildForDownstreamReferences(ref);
+                    }
+                }
+            }
+        }
+        function buildInvalidatedProjects() {
+            buildSomeProjects(function (p) { return context.invalidatedProjects.hasKey(p); });
+        }
+        function buildDependentInvalidatedProjects() {
+            buildSomeProjects(function (p) { return context.queuedProjects.hasKey(p); });
+        }
+        function buildSomeProjects(predicate) {
+            var resolvedNames = resolveProjectNames(rootNames);
+            if (resolvedNames === undefined)
+                return;
+            var graph = createDependencyGraph(resolvedNames);
+            for (var _i = 0, _a = graph.buildQueue; _i < _a.length; _i++) {
+                var next = _a[_i];
+                if (!predicate(next))
+                    continue;
+                var resolved = resolveProjectName(next);
+                if (!resolved)
+                    continue; // ??
+                var proj = configFileCache.parseConfigFile(resolved);
+                if (!proj)
+                    continue; // ?
+                var status = getUpToDateStatus(proj);
+                verboseReportProjectStatus(next, status);
+                if (status.type === UpToDateStatusType.UpstreamBlocked) {
+                    if (context.options.verbose)
+                        buildHost.verbose(ts.Diagnostics.Skipping_build_of_project_0_because_its_dependency_1_has_errors, resolved, status.upstreamProjectName);
+                    continue;
+                }
+                buildSingleProject(next);
+            }
+        }
+        function getAllProjectOutputs(project) {
+            if (project.options.outFile) {
+                return getOutFileOutputs(project);
+            }
+            else {
+                var outputs = [];
+                for (var _i = 0, _a = project.fileNames; _i < _a.length; _i++) {
+                    var inputFile = _a[_i];
+                    outputs.push.apply(outputs, getOutputFileNames(inputFile, project));
+                }
+                return outputs;
+            }
+        }
+        function getUpToDateStatusWorker(project) {
+            var newestInputFileName = undefined;
+            var newestInputFileTime = minimumDate;
+            // Get timestamps of input files
+            for (var _i = 0, _a = project.fileNames; _i < _a.length; _i++) {
+                var inputFile = _a[_i];
+                if (!compilerHost.fileExists(inputFile)) {
+                    return {
+                        type: UpToDateStatusType.Unbuildable,
+                        reason: inputFile + " does not exist"
+                    };
+                }
+                var inputTime = compilerHost.getModifiedTime(inputFile);
+                if (inputTime > newestInputFileTime) {
+                    newestInputFileName = inputFile;
+                    newestInputFileTime = inputTime;
+                }
+            }
+            // Collect the expected outputs of this project
+            var outputs = getAllProjectOutputs(project);
+            if (outputs.length === 0) {
+                return {
+                    type: UpToDateStatusType.ContainerOnly
+                };
+            }
+            // Now see if all outputs are newer than the newest input
+            var oldestOutputFileName = "(none)";
+            var oldestOutputFileTime = maximumDate;
+            var newestOutputFileName = "(none)";
+            var newestOutputFileTime = minimumDate;
+            var missingOutputFileName;
+            var newestDeclarationFileContentChangedTime = minimumDate;
+            var isOutOfDateWithInputs = false;
+            for (var _b = 0, outputs_1 = outputs; _b < outputs_1.length; _b++) {
+                var output = outputs_1[_b];
+                // Output is missing; can stop checking
+                // Don't immediately return because we can still be upstream-blocked, which is a higher-priority status
+                if (!compilerHost.fileExists(output)) {
+                    missingOutputFileName = output;
+                    break;
+                }
+                var outputTime = compilerHost.getModifiedTime(output);
+                if (outputTime < oldestOutputFileTime) {
+                    oldestOutputFileTime = outputTime;
+                    oldestOutputFileName = output;
+                }
+                // If an output is older than the newest input, we can stop checking
+                // Don't immediately return because we can still be upstream-blocked, which is a higher-priority status
+                if (outputTime < newestInputFileTime) {
+                    isOutOfDateWithInputs = true;
+                    break;
+                }
+                if (outputTime > newestOutputFileTime) {
+                    newestOutputFileTime = outputTime;
+                    newestOutputFileName = output;
+                }
+                // Keep track of when the most recent time a .d.ts file was changed.
+                // In addition to file timestamps, we also keep track of when a .d.ts file
+                // had its file touched but not had its contents changed - this allows us
+                // to skip a downstream typecheck
+                if (isDeclarationFile(output)) {
+                    var unchangedTime = context.unchangedOutputs.getValueOrUndefined(output);
+                    if (unchangedTime !== undefined) {
+                        newestDeclarationFileContentChangedTime = newer(unchangedTime, newestDeclarationFileContentChangedTime);
+                    }
+                    else {
+                        newestDeclarationFileContentChangedTime = newer(newestDeclarationFileContentChangedTime, compilerHost.getModifiedTime(output));
+                    }
+                }
+            }
+            var pseudoUpToDate = false;
+            var usesPrepend = false;
+            if (project.projectReferences) {
+                for (var _c = 0, _d = project.projectReferences; _c < _d.length; _c++) {
+                    var ref = _d[_c];
+                    usesPrepend = usesPrepend || !!(ref.prepend);
+                    var resolvedRef = ts.resolveProjectReferencePath(compilerHost, ref);
+                    var refStatus = getUpToDateStatus(configFileCache.parseConfigFile(resolvedRef));
+                    // An upstream project is blocked
+                    if (refStatus.type === UpToDateStatusType.Unbuildable) {
+                        return {
+                            type: UpToDateStatusType.UpstreamBlocked,
+                            upstreamProjectName: ref.path
+                        };
+                    }
+                    // If the upstream project is out of date, then so are we (someone shouldn't have asked, though?)
+                    if (refStatus.type !== UpToDateStatusType.UpToDate) {
+                        return {
+                            type: UpToDateStatusType.UpstreamOutOfDate,
+                            upstreamProjectName: ref.path
+                        };
+                    }
+                    // If the upstream project's newest file is older than our oldest output, we
+                    // can't be out of date because of it
+                    if (refStatus.newestInputFileTime <= oldestOutputFileTime) {
+                        continue;
+                    }
+                    // If the upstream project has only change .d.ts files, and we've built
+                    // *after* those files, then we're "psuedo up to date" and eligible for a fast rebuild
+                    if (refStatus.newestDeclarationFileContentChangedTime <= oldestOutputFileTime) {
+                        pseudoUpToDate = true;
+                        continue;
+                    }
+                    // We have an output older than an upstream output - we are out of date
+                    ts.Debug.assert(oldestOutputFileName !== undefined, "Should have an oldest output filename here");
+                    return {
+                        type: UpToDateStatusType.OutOfDateWithUpstream,
+                        outOfDateOutputFileName: oldestOutputFileName,
+                        newerProjectName: ref.path
+                    };
+                }
+            }
+            if (missingOutputFileName !== undefined) {
+                return {
+                    type: UpToDateStatusType.OutputMissing,
+                    missingOutputFileName: missingOutputFileName
+                };
+            }
+            if (isOutOfDateWithInputs) {
+                return {
+                    type: UpToDateStatusType.OutOfDateWithSelf,
+                    outOfDateOutputFileName: oldestOutputFileName,
+                    newerInputFileName: newestInputFileName
+                };
+            }
+            if (usesPrepend) {
+                pseudoUpToDate = false;
+            }
+            // Up to date
+            return {
+                type: pseudoUpToDate ? UpToDateStatusType.UpToDateWithUpstreamTypes : UpToDateStatusType.UpToDate,
+                newestDeclarationFileContentChangedTime: newestDeclarationFileContentChangedTime,
+                newestInputFileTime: newestInputFileTime,
+                newestOutputFileTime: newestOutputFileTime,
+                newestInputFileName: newestInputFileName,
+                newestOutputFileName: newestOutputFileName,
+                oldestOutputFileName: oldestOutputFileName
+            };
+        }
+        function createDependencyGraph(roots) {
+            var temporaryMarks = {};
+            var permanentMarks = {};
+            var circularityReportStack = [];
+            var buildOrder = [];
+            var graph = createDependencyMapper();
+            var hadError = false;
+            for (var _i = 0, roots_1 = roots; _i < roots_1.length; _i++) {
+                var root = roots_1[_i];
+                visit(root);
+            }
+            if (hadError) {
+                return undefined;
+            }
+            return {
+                buildQueue: buildOrder,
+                dependencyMap: graph
+            };
+            function visit(projPath, inCircularContext) {
+                if (inCircularContext === void 0) { inCircularContext = false; }
+                // Already visited
+                if (permanentMarks[projPath])
+                    return;
+                // Circular
+                if (temporaryMarks[projPath]) {
+                    if (!inCircularContext) {
+                        hadError = true;
+                        buildHost.error(ts.Diagnostics.Project_references_may_not_form_a_circular_graph_Cycle_detected_Colon_0, circularityReportStack.join("\r\n"));
+                        return;
+                    }
+                }
+                temporaryMarks[projPath] = true;
+                circularityReportStack.push(projPath);
+                var parsed = configFileCache.parseConfigFile(projPath);
+                if (parsed === undefined) {
+                    hadError = true;
+                    return;
+                }
+                if (parsed.projectReferences) {
+                    for (var _i = 0, _a = parsed.projectReferences; _i < _a.length; _i++) {
+                        var ref = _a[_i];
+                        var resolvedRefPath = resolveProjectName(ref.path);
+                        if (resolvedRefPath === undefined) {
+                            hadError = true;
+                            break;
+                        }
+                        visit(resolvedRefPath, inCircularContext || ref.circular);
+                        graph.addReference(projPath, resolvedRefPath);
+                    }
+                }
+                circularityReportStack.pop();
+                permanentMarks[projPath] = true;
+                buildOrder.push(projPath);
+            }
+        }
+        function buildSingleProject(proj) {
+            if (context.options.dry) {
+                buildHost.message(ts.Diagnostics.A_non_dry_build_would_build_project_0, proj);
+                return BuildResultFlags.Success;
+            }
+            if (context.options.verbose)
+                buildHost.verbose(ts.Diagnostics.Building_project_0, proj);
+            var resultFlags = BuildResultFlags.None;
+            resultFlags |= BuildResultFlags.DeclarationOutputUnchanged;
+            var configFile = configFileCache.parseConfigFile(proj);
+            if (!configFile) {
+                // Failed to read the config file
+                resultFlags |= BuildResultFlags.ConfigFileErrors;
+                context.projectStatus.setValue(proj, { type: UpToDateStatusType.Unbuildable, reason: "Config file errors" });
+                return resultFlags;
+            }
+            if (configFile.fileNames.length === 0) {
+                // Nothing to build - must be a solution file, basically
+                return BuildResultFlags.None;
+            }
+            var programOptions = {
+                projectReferences: configFile.projectReferences,
+                host: compilerHost,
+                rootNames: configFile.fileNames,
+                options: configFile.options
+            };
+            var program = ts.createProgram(programOptions);
+            // Don't emit anything in the presence of syntactic errors or options diagnostics
+            var syntaxDiagnostics = program.getOptionsDiagnostics().concat(program.getSyntacticDiagnostics());
+            if (syntaxDiagnostics.length) {
+                resultFlags |= BuildResultFlags.SyntaxErrors;
+                for (var _i = 0, syntaxDiagnostics_1 = syntaxDiagnostics; _i < syntaxDiagnostics_1.length; _i++) {
+                    var diag = syntaxDiagnostics_1[_i];
+                    buildHost.errorDiagnostic(diag);
+                }
+                context.projectStatus.setValue(proj, { type: UpToDateStatusType.Unbuildable, reason: "Syntactic errors" });
+                return resultFlags;
+            }
+            // Don't emit .d.ts if there are decl file errors
+            if (program.getCompilerOptions().declaration) {
+                var declDiagnostics = program.getDeclarationDiagnostics();
+                if (declDiagnostics.length) {
+                    resultFlags |= BuildResultFlags.DeclarationEmitErrors;
+                    for (var _a = 0, declDiagnostics_1 = declDiagnostics; _a < declDiagnostics_1.length; _a++) {
+                        var diag = declDiagnostics_1[_a];
+                        buildHost.errorDiagnostic(diag);
+                    }
+                    context.projectStatus.setValue(proj, { type: UpToDateStatusType.Unbuildable, reason: "Declaration file errors" });
+                    return resultFlags;
+                }
+            }
+            // Same as above but now for semantic diagnostics
+            var semanticDiagnostics = program.getSemanticDiagnostics();
+            if (semanticDiagnostics.length) {
+                resultFlags |= BuildResultFlags.TypeErrors;
+                for (var _b = 0, semanticDiagnostics_1 = semanticDiagnostics; _b < semanticDiagnostics_1.length; _b++) {
+                    var diag = semanticDiagnostics_1[_b];
+                    buildHost.errorDiagnostic(diag);
+                }
+                context.projectStatus.setValue(proj, { type: UpToDateStatusType.Unbuildable, reason: "Semantic errors" });
+                return resultFlags;
+            }
+            var newestDeclarationFileContentChangedTime = minimumDate;
+            program.emit(/*targetSourceFile*/ undefined, function (fileName, content, writeBom, onError) {
+                var priorChangeTime;
+                if (isDeclarationFile(fileName) && compilerHost.fileExists(fileName)) {
+                    if (compilerHost.readFile(fileName) === content) {
+                        // Check for unchanged .d.ts files
+                        resultFlags &= ~BuildResultFlags.DeclarationOutputUnchanged;
+                        priorChangeTime = compilerHost.getModifiedTime && compilerHost.getModifiedTime(fileName);
+                    }
+                }
+                compilerHost.writeFile(fileName, content, writeBom, onError, ts.emptyArray);
+                if (priorChangeTime !== undefined) {
+                    newestDeclarationFileContentChangedTime = newer(priorChangeTime, newestDeclarationFileContentChangedTime);
+                    context.unchangedOutputs.setValue(fileName, priorChangeTime);
+                }
+            });
+            context.projectStatus.setValue(proj, { type: UpToDateStatusType.UpToDate, newestDeclarationFileContentChangedTime: newestDeclarationFileContentChangedTime });
+            return resultFlags;
+        }
+        function updateOutputTimestamps(proj) {
+            if (context.options.dry) {
+                return buildHost.message(ts.Diagnostics.A_non_dry_build_would_build_project_0, proj.options.configFilePath);
+            }
+            if (context.options.verbose)
+                buildHost.verbose(ts.Diagnostics.Updating_output_timestamps_of_project_0, proj.options.configFilePath);
+            var now = new Date();
+            var outputs = getAllProjectOutputs(proj);
+            var priorNewestUpdateTime = minimumDate;
+            for (var _i = 0, outputs_2 = outputs; _i < outputs_2.length; _i++) {
+                var file = outputs_2[_i];
+                if (isDeclarationFile(file)) {
+                    priorNewestUpdateTime = newer(priorNewestUpdateTime, compilerHost.getModifiedTime(file));
+                }
+                compilerHost.setModifiedTime(file, now);
+            }
+            context.projectStatus.setValue(proj.options.configFilePath, { type: UpToDateStatusType.UpToDate, newestDeclarationFileContentChangedTime: priorNewestUpdateTime });
+        }
+        function getFilesToClean(configFileNames) {
+            var resolvedNames = resolveProjectNames(configFileNames);
+            if (resolvedNames === undefined)
+                return undefined;
+            // Get the same graph for cleaning we'd use for building
+            var graph = createDependencyGraph(resolvedNames);
+            if (graph === undefined)
+                return undefined;
+            var filesToDelete = [];
+            for (var _i = 0, _a = graph.buildQueue; _i < _a.length; _i++) {
+                var proj = _a[_i];
+                var parsed = configFileCache.parseConfigFile(proj);
+                if (parsed === undefined) {
+                    // File has gone missing; fine to ignore here
+                    continue;
+                }
+                var outputs = getAllProjectOutputs(parsed);
+                for (var _b = 0, outputs_3 = outputs; _b < outputs_3.length; _b++) {
+                    var output = outputs_3[_b];
+                    if (compilerHost.fileExists(output)) {
+                        filesToDelete.push(output);
+                    }
+                }
+            }
+            return filesToDelete;
+        }
+        function getAllProjectsInScope() {
+            var resolvedNames = resolveProjectNames(rootNames);
+            if (resolvedNames === undefined)
+                return undefined;
+            var graph = createDependencyGraph(resolvedNames);
+            if (graph === undefined)
+                return undefined;
+            return graph.buildQueue;
+        }
+        function cleanAllProjects() {
+            var resolvedNames = getAllProjectsInScope();
+            if (resolvedNames === undefined) {
+                buildHost.message(ts.Diagnostics.Skipping_clean_because_not_all_projects_could_be_located);
+                return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
+            }
+            var filesToDelete = getFilesToClean(resolvedNames);
+            if (filesToDelete === undefined) {
+                buildHost.message(ts.Diagnostics.Skipping_clean_because_not_all_projects_could_be_located);
+                return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
+            }
+            if (context.options.dry) {
+                buildHost.message(ts.Diagnostics.A_non_dry_build_would_delete_the_following_files_Colon_0, filesToDelete.map(function (f) { return "\r\n * " + f; }).join(""));
+                return ts.ExitStatus.Success;
+            }
+            // Do this check later to allow --clean --dry to function even if the host can't delete files
+            if (!compilerHost.deleteFile) {
+                throw new Error("Host does not support deleting files");
+            }
+            for (var _i = 0, filesToDelete_1 = filesToDelete; _i < filesToDelete_1.length; _i++) {
+                var output = filesToDelete_1[_i];
+                compilerHost.deleteFile(output);
+            }
+            return ts.ExitStatus.Success;
+        }
+        function resolveProjectName(name) {
+            var fullPath = ts.resolvePath(compilerHost.getCurrentDirectory(), name);
+            if (compilerHost.fileExists(fullPath)) {
+                return fullPath;
+            }
+            var fullPathWithTsconfig = ts.combinePaths(fullPath, "tsconfig.json");
+            if (compilerHost.fileExists(fullPathWithTsconfig)) {
+                return fullPathWithTsconfig;
+            }
+            buildHost.error(ts.Diagnostics.File_0_not_found, relName(fullPath));
+            return undefined;
+        }
+        function resolveProjectNames(configFileNames) {
+            var resolvedNames = [];
+            for (var _i = 0, configFileNames_1 = configFileNames; _i < configFileNames_1.length; _i++) {
+                var name = configFileNames_1[_i];
+                var resolved = resolveProjectName(name);
+                if (resolved === undefined) {
+                    return undefined;
+                }
+                resolvedNames.push(resolved);
+            }
+            return resolvedNames;
+        }
+        function buildAllProjects() {
+            var graph = getGlobalDependencyGraph();
+            if (graph === undefined)
+                return ts.ExitStatus.DiagnosticsPresent_OutputsSkipped;
+            var queue = graph.buildQueue;
+            reportBuildQueue(graph);
+            var anyFailed = false;
+            for (var _i = 0, queue_1 = queue; _i < queue_1.length; _i++) {
+                var next = queue_1[_i];
+                var proj = configFileCache.parseConfigFile(next);
+                if (proj === undefined) {
+                    anyFailed = true;
+                    break;
+                }
+                var status = getUpToDateStatus(proj);
+                verboseReportProjectStatus(next, status);
+                var projName = proj.options.configFilePath;
+                if (status.type === UpToDateStatusType.UpToDate && !context.options.force) {
+                    // Up to date, skip
+                    if (defaultOptions.dry) {
+                        // In a dry build, inform the user of this fact
+                        buildHost.message(ts.Diagnostics.Project_0_is_up_to_date, projName);
+                    }
+                    continue;
+                }
+                if (status.type === UpToDateStatusType.UpToDateWithUpstreamTypes && !context.options.force) {
+                    // Fake build
+                    updateOutputTimestamps(proj);
+                    continue;
+                }
+                if (status.type === UpToDateStatusType.UpstreamBlocked) {
+                    if (context.options.verbose)
+                        buildHost.verbose(ts.Diagnostics.Skipping_build_of_project_0_because_its_dependency_1_has_errors, projName, status.upstreamProjectName);
+                    continue;
+                }
+                if (status.type === UpToDateStatusType.ContainerOnly) {
+                    // Do nothing
+                    continue;
+                }
+                var buildResult = buildSingleProject(next);
+                anyFailed = anyFailed || !!(buildResult & BuildResultFlags.AnyErrors);
+            }
+            return anyFailed ? ts.ExitStatus.DiagnosticsPresent_OutputsSkipped : ts.ExitStatus.Success;
+        }
+        /**
+         * Report the build ordering inferred from the current project graph if we're in verbose mode
+         */
+        function reportBuildQueue(graph) {
+            if (!context.options.verbose)
+                return;
+            var names = [];
+            for (var _i = 0, _a = graph.buildQueue; _i < _a.length; _i++) {
+                var name = _a[_i];
+                names.push(name);
+            }
+            if (context.options.verbose)
+                buildHost.verbose(ts.Diagnostics.Projects_in_this_build_Colon_0, names.map(function (s) { return "\r\n    * " + relName(s); }).join(""));
+        }
+        function relName(path) {
+            return ts.convertToRelativePath(path, compilerHost.getCurrentDirectory(), function (f) { return compilerHost.getCanonicalFileName(f); });
+        }
+        /**
+         * Report the up-to-date status of a project if we're in verbose mode
+         */
+        function verboseReportProjectStatus(configFileName, status) {
+            if (!context.options.verbose)
+                return;
+            switch (status.type) {
+                case UpToDateStatusType.OutOfDateWithSelf:
+                    return buildHost.verbose(ts.Diagnostics.Project_0_is_out_of_date_because_oldest_output_1_is_older_than_newest_input_2, relName(configFileName), relName(status.outOfDateOutputFileName), relName(status.newerInputFileName));
+                case UpToDateStatusType.OutOfDateWithUpstream:
+                    return buildHost.verbose(ts.Diagnostics.Project_0_is_out_of_date_because_oldest_output_1_is_older_than_newest_input_2, relName(configFileName), relName(status.outOfDateOutputFileName), relName(status.newerProjectName));
+                case UpToDateStatusType.OutputMissing:
+                    return buildHost.verbose(ts.Diagnostics.Project_0_is_out_of_date_because_output_file_1_does_not_exist, relName(configFileName), relName(status.missingOutputFileName));
+                case UpToDateStatusType.UpToDate:
+                    if (status.newestInputFileTime !== undefined) {
+                        return buildHost.verbose(ts.Diagnostics.Project_0_is_up_to_date_because_newest_input_1_is_older_than_oldest_output_2, relName(configFileName), relName(status.newestInputFileName), relName(status.oldestOutputFileName));
+                    }
+                    // Don't report anything for "up to date because it was already built" -- too verbose
+                    break;
+                case UpToDateStatusType.UpToDateWithUpstreamTypes:
+                    return buildHost.verbose(ts.Diagnostics.Project_0_is_up_to_date_with_d_ts_files_from_its_dependencies, relName(configFileName));
+                case UpToDateStatusType.UpstreamOutOfDate:
+                    return buildHost.verbose(ts.Diagnostics.Project_0_is_out_of_date_because_its_dependency_1_is_out_of_date, relName(configFileName), relName(status.upstreamProjectName));
+                case UpToDateStatusType.UpstreamBlocked:
+                    return buildHost.verbose(ts.Diagnostics.Project_0_can_t_be_built_because_its_dependency_1_has_errors, relName(configFileName), relName(status.upstreamProjectName));
+                case UpToDateStatusType.Unbuildable:
+                    return buildHost.verbose(ts.Diagnostics.Failed_to_parse_file_0_Colon_1, relName(configFileName), status.reason);
+                case UpToDateStatusType.ContainerOnly:
+                    // Don't report status on "solution" projects
+                    break;
+                default:
+                    ts.assertTypeIsNever(status);
+            }
+        }
+    }
+    ts.createSolutionBuilder = createSolutionBuilder;
+})(ts || (ts = {}));
+//# sourceMappingURL=compiler.js.map
 "use strict";
+/* @internal */
 var ts;
 (function (ts) {
     var server;
diff --git a/lib/watchGuard.js b/lib/watchGuard.js
index 10b0c1e11ba..c89356b0dc3 100644
--- a/lib/watchGuard.js
+++ b/lib/watchGuard.js
@@ -1,3 +1,19 @@
+/*! *****************************************************************************
+Copyright (c) Microsoft Corporation. All rights reserved. 
+Licensed under the Apache License, Version 2.0 (the "License"); you may not use
+this file except in compliance with the License. You may obtain a copy of the
+License at http://www.apache.org/licenses/LICENSE-2.0  
+ 
+THIS CODE IS PROVIDED ON AN *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED
+WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE, 
+MERCHANTABLITY OR NON-INFRINGEMENT. 
+ 
+See the Apache Version 2.0 License for specific language governing permissions
+and limitations under the License.
+***************************************************************************** */
+
+
 "use strict";
 if (process.argv.length < 3) {
     process.exit(1);