Support symbol literals.

sdk/lib/_internal/compiler/implementation/scanner/parser.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of scanner;
 
 /**
  * An event generating parser of Dart programs. This parser expects
  * all tokens in a linked list (aka a token stream).
  *
@@ skipping 1654 matching lines @@
     final kind = token.kind;
     if (identical(kind, IDENTIFIER_TOKEN)) {
       return parseSendOrFunctionLiteral(token);
     } else if (identical(kind, INT_TOKEN)
         || identical(kind, HEXADECIMAL_TOKEN)) {
       return parseLiteralInt(token);
     } else if (identical(kind, DOUBLE_TOKEN)) {
       return parseLiteralDouble(token);
     } else if (identical(kind, STRING_TOKEN)) {
       return parseLiteralString(token);
+    } else if (identical(kind, HASH_TOKEN)) {
+      return parseLiteralSymbol(token);
     } else if (identical(kind, KEYWORD_TOKEN)) {
       final value = token.stringValue;
       if ((identical(value, 'true')) || (identical(value, 'false'))) {
         return parseLiteralBool(token);
       } else if (identical(value, 'null')) {
         return parseLiteralNull(token);
       } else if (identical(value, 'this')) {
         return parseThisExpression(token);
       } else if (identical(value, 'super')) {
         return parseSuperExpression(token);
@@ skipping 200 matching lines @@
     while (identical(token.kind, STRING_TOKEN)) {
       token = parseSingleLiteralString(token);
       count++;
     }
     if (count > 1) {
       listener.handleStringJuxtaposition(count);
     }
     return token;
   }
 
+  Token parseLiteralSymbol(Token token) {
+    Token hashToken = token;
+    listener.beginLiteralSymbol(hashToken);
+    token = token.next;
+    if (isUserDefinableOperator(token.stringValue)) {
+      listener.handleOperator(token);
+      listener.endLiteralSymbol(hashToken, 1);
+      return token.next;
+    } else {
+      int count = 1;
+      token = parseIdentifier(token);
+      while (identical(token.stringValue, '.')) {
+        count++;
+        token = parseIdentifier(token.next);
+      }
+      listener.endLiteralSymbol(hashToken, count);
+      return token;
+    }
+  }
+
   /**
    * Only called when [:token.kind === STRING_TOKEN:].
    */
   Token parseSingleLiteralString(Token token) {
     listener.beginLiteralString(token);
     // Parsing the prefix, for instance 'x of 'x${id}y${id}z'
     token = token.next;
     int interpolationCount = 0;
     var kind = token.kind;
     while (kind != EOF_TOKEN) {
@@ skipping 452 matching lines @@
     }
     listener.handleContinueStatement(hasTarget, continueKeyword, token);
     return expectSemicolon(token);
   }
 
   Token parseEmptyStatement(Token token) {
     listener.handleEmptyStatement(token);
     return expectSemicolon(token);
   }
 }