diff --git a/src/compiler/parser.ts b/src/compiler/parser.ts
index ce2ad27329e..6503e6bf421 100644
--- a/src/compiler/parser.ts
+++ b/src/compiler/parser.ts
@@ -6276,17 +6276,17 @@ namespace ts {
                         indent += text.length;
                     }
 
-                    nextJSDocToken();
-                    while (token() === SyntaxKind.WhitespaceTrivia) {
-                        nextJSDocToken();
+                    let t = nextJSDocToken();
+                    while (t === SyntaxKind.WhitespaceTrivia) {
+                        t = nextJSDocToken();
                     }
-                    if (token() === SyntaxKind.NewLineTrivia) {
+                    if (t === SyntaxKind.NewLineTrivia) {
                         state = JSDocState.BeginningOfLine;
                         indent = 0;
-                        nextJSDocToken();
+                        t = nextJSDocToken();
                     }
-                    while (token() !== SyntaxKind.EndOfFileToken) {
-                        switch (token()) {
+                    loop: while (true) {
+                        switch (t) {
                             case SyntaxKind.AtToken:
                                 if (state === JSDocState.BeginningOfLine || state === JSDocState.SawAsterisk) {
                                     removeTrailingNewlines(comments);
@@ -6340,7 +6340,7 @@ namespace ts {
                                 indent += whitespace.length;
                                 break;
                             case SyntaxKind.EndOfFileToken:
-                                break;
+                                break loop;
                             default:
                                 // anything other than whitespace or asterisk at the beginning of the line starts the comment text
                                 state = JSDocState.SavingComments;
@@ -6348,10 +6348,11 @@ namespace ts {
                                 break;
                         }
                         if (advanceToken) {
-                            nextJSDocToken();
+                            t = nextJSDocToken();
                         }
                         else {
                             advanceToken = true;
+                            t = currentToken as JsDocSyntaxKind;
                         }
                     }
                     removeLeadingNewlines(comments);
@@ -6462,8 +6463,9 @@ namespace ts {
                         comments.push(text);
                         indent += text.length;
                     }
-                    while (token() !== SyntaxKind.AtToken && token() !== SyntaxKind.EndOfFileToken) {
-                        switch (token()) {
+                    let tok = token() as JsDocSyntaxKind;
+                    loop: while (true) {
+                        switch (tok) {
                             case SyntaxKind.NewLineTrivia:
                                 if (state >= JSDocState.SawAsterisk) {
                                     state = JSDocState.BeginningOfLine;
@@ -6472,8 +6474,9 @@ namespace ts {
                                 indent = 0;
                                 break;
                             case SyntaxKind.AtToken:
+                            case SyntaxKind.EndOfFileToken:
                                 // Done
-                                break;
+                                break loop;
                             case SyntaxKind.WhitespaceTrivia:
                                 if (state === JSDocState.SavingComments) {
                                     pushComment(scanner.getTokenText());
@@ -6501,11 +6504,7 @@ namespace ts {
                                 pushComment(scanner.getTokenText());
                                 break;
                         }
-                        if (token() === SyntaxKind.AtToken) {
-                            // Done
-                            break;
-                        }
-                        nextJSDocToken();
+                        tok = nextJSDocToken();
                     }
 
                     removeLeadingNewlines(comments);
@@ -6783,8 +6782,7 @@ namespace ts {
                     let canParseTag = true;
                     let seenAsterisk = false;
                     while (true) {
-                        nextJSDocToken();
-                        switch (token()) {
+                        switch (nextJSDocToken()) {
                             case SyntaxKind.AtToken:
                                 if (canParseTag) {
                                     const child = tryParseChildTag(target);
@@ -6880,7 +6878,7 @@ namespace ts {
                     return result;
                 }
 
-                function nextJSDocToken(): SyntaxKind {
+                function nextJSDocToken(): JsDocSyntaxKind {
                     return currentToken = scanner.scanJSDocToken();
                 }
 
diff --git a/src/compiler/scanner.ts b/src/compiler/scanner.ts
index e4f7821897d..c8bb2ec0a25 100644
--- a/src/compiler/scanner.ts
+++ b/src/compiler/scanner.ts
@@ -35,7 +35,7 @@ namespace ts {
         scanJsxAttributeValue(): SyntaxKind;
         reScanJsxToken(): SyntaxKind;
         scanJsxToken(): SyntaxKind;
-        scanJSDocToken(): SyntaxKind;
+        scanJSDocToken(): JsDocSyntaxKind;
         scan(): SyntaxKind;
         getText(): string;
         // Sets the text for the scanner to scan.  An optional subrange starting point and length
@@ -1905,7 +1905,7 @@ namespace ts {
                         break;
                     }
                 }
-                tokenValue += text.substr(firstCharPosition, pos - firstCharPosition);
+                tokenValue += text.substring(firstCharPosition, pos);
             }
             return token;
         }
@@ -1924,7 +1924,7 @@ namespace ts {
             }
         }
 
-        function scanJSDocToken(): SyntaxKind {
+        function scanJSDocToken(): JsDocSyntaxKind {
             if (pos >= end) {
                 return token = SyntaxKind.EndOfFileToken;
             }
@@ -1933,6 +1933,7 @@ namespace ts {
             tokenPos = pos;
 
             const ch = text.charCodeAt(pos);
+            pos++;
             switch (ch) {
                 case CharacterCodes.tab:
                 case CharacterCodes.verticalTab:
@@ -1943,56 +1944,31 @@ namespace ts {
                     }
                     return token = SyntaxKind.WhitespaceTrivia;
                 case CharacterCodes.at:
-                    pos++;
                     return token = SyntaxKind.AtToken;
                 case CharacterCodes.lineFeed:
                 case CharacterCodes.carriageReturn:
-                    pos++;
                     return token = SyntaxKind.NewLineTrivia;
                 case CharacterCodes.asterisk:
-                    pos++;
                     return token = SyntaxKind.AsteriskToken;
                 case CharacterCodes.openBrace:
-                    pos++;
                     return token = SyntaxKind.OpenBraceToken;
                 case CharacterCodes.closeBrace:
-                    pos++;
                     return token = SyntaxKind.CloseBraceToken;
                 case CharacterCodes.openBracket:
-                    pos++;
                     return token = SyntaxKind.OpenBracketToken;
                 case CharacterCodes.closeBracket:
-                    pos++;
                     return token = SyntaxKind.CloseBracketToken;
                 case CharacterCodes.lessThan:
-                    pos++;
                     return token = SyntaxKind.LessThanToken;
-                case CharacterCodes.greaterThan:
-                    pos++;
-                    return token = SyntaxKind.GreaterThanToken;
                 case CharacterCodes.equals:
-                    pos++;
                     return token = SyntaxKind.EqualsToken;
                 case CharacterCodes.comma:
-                    pos++;
                     return token = SyntaxKind.CommaToken;
                 case CharacterCodes.dot:
-                    pos++;
-                    if (text.substr(tokenPos, pos + 2) === "...") {
-                        pos += 2;
-                        return token = SyntaxKind.DotDotDotToken;
-                    }
                     return token = SyntaxKind.DotToken;
-                case CharacterCodes.exclamation:
-                    pos++;
-                    return token = SyntaxKind.ExclamationToken;
-                case CharacterCodes.question:
-                    pos++;
-                    return token = SyntaxKind.QuestionToken;
             }
 
             if (isIdentifierStart(ch, ScriptTarget.Latest)) {
-                pos++;
                 while (isIdentifierPart(text.charCodeAt(pos), ScriptTarget.Latest) && pos < end) {
                     pos++;
                 }
@@ -2000,7 +1976,7 @@ namespace ts {
                 return token = SyntaxKind.Identifier;
             }
             else {
-                return pos += 1, token = SyntaxKind.Unknown;
+                return token = SyntaxKind.Unknown;
             }
         }
 
diff --git a/src/compiler/types.ts b/src/compiler/types.ts
index 6e69b46e73d..21fe9537424 100644
--- a/src/compiler/types.ts
+++ b/src/compiler/types.ts
@@ -58,6 +58,23 @@ namespace ts {
         end: number;
     }
 
+    export type JsDocSyntaxKind =
+        | SyntaxKind.EndOfFileToken
+        | SyntaxKind.WhitespaceTrivia
+        | SyntaxKind.AtToken
+        | SyntaxKind.NewLineTrivia
+        | SyntaxKind.AsteriskToken
+        | SyntaxKind.OpenBraceToken
+        | SyntaxKind.CloseBraceToken
+        | SyntaxKind.LessThanToken
+        | SyntaxKind.OpenBracketToken
+        | SyntaxKind.CloseBracketToken
+        | SyntaxKind.EqualsToken
+        | SyntaxKind.CommaToken
+        | SyntaxKind.DotToken
+        | SyntaxKind.Identifier
+        | SyntaxKind.Unknown;
+
     // token > SyntaxKind.Identifer => token is a keyword
     // Also, If you add a new SyntaxKind be sure to keep the `Markers` section at the bottom in sync
     export const enum SyntaxKind {
diff --git a/tests/baselines/reference/api/tsserverlibrary.d.ts b/tests/baselines/reference/api/tsserverlibrary.d.ts
index 495e6083f4b..ab39eca1111 100644
--- a/tests/baselines/reference/api/tsserverlibrary.d.ts
+++ b/tests/baselines/reference/api/tsserverlibrary.d.ts
@@ -59,6 +59,7 @@ declare namespace ts {
         pos: number;
         end: number;
     }
+    type JsDocSyntaxKind = SyntaxKind.EndOfFileToken | SyntaxKind.WhitespaceTrivia | SyntaxKind.AtToken | SyntaxKind.NewLineTrivia | SyntaxKind.AsteriskToken | SyntaxKind.OpenBraceToken | SyntaxKind.CloseBraceToken | SyntaxKind.LessThanToken | SyntaxKind.OpenBracketToken | SyntaxKind.CloseBracketToken | SyntaxKind.EqualsToken | SyntaxKind.CommaToken | SyntaxKind.DotToken | SyntaxKind.Identifier | SyntaxKind.Unknown;
     enum SyntaxKind {
         Unknown = 0,
         EndOfFileToken = 1,
@@ -3127,7 +3128,7 @@ declare namespace ts {
         scanJsxAttributeValue(): SyntaxKind;
         reScanJsxToken(): SyntaxKind;
         scanJsxToken(): SyntaxKind;
-        scanJSDocToken(): SyntaxKind;
+        scanJSDocToken(): JsDocSyntaxKind;
         scan(): SyntaxKind;
         getText(): string;
         setText(text: string, start?: number, length?: number): void;
diff --git a/tests/baselines/reference/api/typescript.d.ts b/tests/baselines/reference/api/typescript.d.ts
index 5563d95aa0c..df6f3362c74 100644
--- a/tests/baselines/reference/api/typescript.d.ts
+++ b/tests/baselines/reference/api/typescript.d.ts
@@ -59,6 +59,7 @@ declare namespace ts {
         pos: number;
         end: number;
     }
+    type JsDocSyntaxKind = SyntaxKind.EndOfFileToken | SyntaxKind.WhitespaceTrivia | SyntaxKind.AtToken | SyntaxKind.NewLineTrivia | SyntaxKind.AsteriskToken | SyntaxKind.OpenBraceToken | SyntaxKind.CloseBraceToken | SyntaxKind.LessThanToken | SyntaxKind.OpenBracketToken | SyntaxKind.CloseBracketToken | SyntaxKind.EqualsToken | SyntaxKind.CommaToken | SyntaxKind.DotToken | SyntaxKind.Identifier | SyntaxKind.Unknown;
     enum SyntaxKind {
         Unknown = 0,
         EndOfFileToken = 1,
@@ -2788,7 +2789,7 @@ declare namespace ts {
         scanJsxAttributeValue(): SyntaxKind;
         reScanJsxToken(): SyntaxKind;
         scanJsxToken(): SyntaxKind;
-        scanJSDocToken(): SyntaxKind;
+        scanJSDocToken(): JsDocSyntaxKind;
         scan(): SyntaxKind;
         getText(): string;
         setText(text: string, start?: number, length?: number): void;