diff --git a/src/compiler/parser.ts b/src/compiler/parser.ts
index b0cf4131595..6e3ccdb5998 100644
--- a/src/compiler/parser.ts
+++ b/src/compiler/parser.ts
@@ -979,10 +979,7 @@ namespace ts {
         }
 
         function parseErrorAtCurrentToken(message: DiagnosticMessage, arg0?: any): void {
-            const start = scanner.getTokenPos();
-            const length = scanner.getTextPos() - start;
-
-            parseErrorAtPosition(start, length, message, arg0);
+            parseErrorAt(scanner.getTokenPos(), scanner.getTextPos(), message, arg0);
         }
 
         function parseErrorAtPosition(start: number, length: number, message: DiagnosticMessage, arg0?: any): void {
@@ -997,9 +994,16 @@ namespace ts {
             parseErrorBeforeNextFinishedNode = true;
         }
 
-        function scanError(message: DiagnosticMessage, length?: number) {
-            const pos = scanner.getTextPos();
-            parseErrorAtPosition(pos, length || 0, message);
+        function parseErrorAt(start: number, end: number, message: DiagnosticMessage, arg0?: any): void {
+            parseErrorAtPosition(start, end - start, message, arg0);
+        }
+
+        function parseErrorAtRange(range: TextRange, message: DiagnosticMessage, arg0?: any): void {
+            parseErrorAt(range.pos, range.end, message, arg0);
+        }
+
+        function scanError(message: DiagnosticMessage, length: number): void {
+            parseErrorAtPosition(scanner.getTextPos(), length, message);
         }
 
         function getNodePos(): number {
@@ -3809,12 +3813,13 @@ namespace ts {
             const unaryOperator = token();
             const simpleUnaryExpression = parseSimpleUnaryExpression();
             if (token() === SyntaxKind.AsteriskAsteriskToken) {
-                const start = skipTrivia(sourceText, simpleUnaryExpression.pos);
+                const pos = skipTrivia(sourceText, simpleUnaryExpression.pos);
+                const { end } = simpleUnaryExpression;
                 if (simpleUnaryExpression.kind === SyntaxKind.TypeAssertionExpression) {
-                    parseErrorAtPosition(start, simpleUnaryExpression.end - start, Diagnostics.A_type_assertion_expression_is_not_allowed_in_the_left_hand_side_of_an_exponentiation_expression_Consider_enclosing_the_expression_in_parentheses);
+                    parseErrorAt(pos, end, Diagnostics.A_type_assertion_expression_is_not_allowed_in_the_left_hand_side_of_an_exponentiation_expression_Consider_enclosing_the_expression_in_parentheses);
                 }
                 else {
-                    parseErrorAtPosition(start, simpleUnaryExpression.end - start, Diagnostics.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, tokenToString(unaryOperator));
+                    parseErrorAt(pos, end, Diagnostics.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, tokenToString(unaryOperator));
                 }
             }
             return simpleUnaryExpression;
@@ -4085,7 +4090,7 @@ namespace ts {
                 node.closingElement = parseJsxClosingElement(inExpressionContext);
 
                 if (!tagNamesAreEquivalent(node.openingElement.tagName, node.closingElement.tagName)) {
-                    parseErrorAtPosition(node.closingElement.pos, node.closingElement.end - node.closingElement.pos, Diagnostics.Expected_corresponding_JSX_closing_tag_for_0, getTextOfNodeFromSourceText(sourceText, node.openingElement.tagName));
+                    parseErrorAtRange(node.closingElement, Diagnostics.Expected_corresponding_JSX_closing_tag_for_0, getTextOfNodeFromSourceText(sourceText, node.openingElement.tagName));
                 }
 
                 result = finishNode(node);
@@ -4141,11 +4146,10 @@ namespace ts {
                     // If we hit EOF, issue the error at the tag that lacks the closing element
                     // rather than at the end of the file (which is useless)
                     if (isJsxOpeningFragment(openingTag)) {
-                        parseErrorAtPosition(openingTag.pos, openingTag.end - openingTag.pos, Diagnostics.JSX_fragment_has_no_corresponding_closing_tag);
+                        parseErrorAtRange(openingTag, Diagnostics.JSX_fragment_has_no_corresponding_closing_tag);
                     }
                     else {
-                        const openingTagName = openingTag.tagName;
-                        parseErrorAtPosition(openingTagName.pos, openingTagName.end - openingTagName.pos, Diagnostics.JSX_element_0_has_no_corresponding_closing_tag, getTextOfNodeFromSourceText(sourceText, openingTagName));
+                        parseErrorAtRange(openingTag.tagName, Diagnostics.JSX_element_0_has_no_corresponding_closing_tag, getTextOfNodeFromSourceText(sourceText, openingTag.tagName));
                     }
                     return undefined;
                 case SyntaxKind.LessThanSlashToken:
@@ -4317,8 +4321,7 @@ namespace ts {
             const node = <JsxClosingFragment>createNode(SyntaxKind.JsxClosingFragment);
             parseExpected(SyntaxKind.LessThanSlashToken);
             if (tokenIsIdentifierOrKeyword(token())) {
-                const unexpectedTagName = parseJsxElementName();
-                parseErrorAtPosition(unexpectedTagName.pos, unexpectedTagName.end - unexpectedTagName.pos, Diagnostics.Expected_corresponding_closing_tag_for_JSX_fragment);
+                parseErrorAtRange(parseJsxElementName(), Diagnostics.Expected_corresponding_closing_tag_for_JSX_fragment);
             }
             if (inExpressionContext) {
                 parseExpected(SyntaxKind.GreaterThanToken);
@@ -6066,8 +6069,7 @@ namespace ts {
                 node.name = identifierName;
             }
             if (kind === SyntaxKind.ImportSpecifier && checkIdentifierIsKeyword) {
-                // Report error identifier expected
-                parseErrorAtPosition(checkIdentifierStart, checkIdentifierEnd - checkIdentifierStart, Diagnostics.Identifier_expected);
+                parseErrorAt(checkIdentifierStart, checkIdentifierEnd, Diagnostics.Identifier_expected);
             }
             return finishNode(node);
         }
@@ -6591,7 +6593,7 @@ namespace ts {
 
                 function parseReturnTag(atToken: AtToken, tagName: Identifier): JSDocReturnTag {
                     if (forEach(tags, t => t.kind === SyntaxKind.JSDocReturnTag)) {
-                        parseErrorAtPosition(tagName.pos, scanner.getTokenPos() - tagName.pos, Diagnostics._0_tag_already_specified, tagName.escapedText);
+                        parseErrorAt(tagName.pos, scanner.getTokenPos(), Diagnostics._0_tag_already_specified, tagName.escapedText);
                     }
 
                     const result = <JSDocReturnTag>createNode(SyntaxKind.JSDocReturnTag, atToken.pos);
@@ -6603,7 +6605,7 @@ namespace ts {
 
                 function parseTypeTag(atToken: AtToken, tagName: Identifier): JSDocTypeTag {
                     if (forEach(tags, t => t.kind === SyntaxKind.JSDocTypeTag)) {
-                        parseErrorAtPosition(tagName.pos, scanner.getTokenPos() - tagName.pos, Diagnostics._0_tag_already_specified, tagName.escapedText);
+                        parseErrorAt(tagName.pos, scanner.getTokenPos(), Diagnostics._0_tag_already_specified, tagName.escapedText);
                     }
 
                     const result = <JSDocTypeTag>createNode(SyntaxKind.JSDocTypeTag, atToken.pos);
@@ -6813,7 +6815,7 @@ namespace ts {
 
                 function parseTemplateTag(atToken: AtToken, tagName: Identifier): JSDocTemplateTag | undefined {
                     if (some(tags, isJSDocTemplateTag)) {
-                        parseErrorAtPosition(tagName.pos, scanner.getTokenPos() - tagName.pos, Diagnostics._0_tag_already_specified, tagName.escapedText);
+                        parseErrorAt(tagName.pos, scanner.getTokenPos(), Diagnostics._0_tag_already_specified, tagName.escapedText);
                     }
 
                     // Type parameter list looks like '@template T,U,V'