move csslib into dart svn

pkg/csslib/lib/src/token.dart

-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// 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 csslib.parser;
+
 /**
  * A single token in the Dart language.
  */
 class Token {
   /** A member of [TokenKind] specifying what kind of token this is. */
   final int kind;
 
-  /** The [SourceFile] this token came from. */
-  final SourceFile source;
+  /** The location where this token was parsed from. */
+  final Span span;
 
-  /** The start and end indexes into the [SourceFile] of this [Token]. */
-  final int start, end;
+  /** The start offset of this token. */
+  int get start => span.start.offset;
 
-  Token(this.kind, this.source, this.start, this.end) {}
-
-  Token.fake(this.kind, span)
-    : this.source = span.file, this.start = span.start, this.end = span.end;
+  /** The end offset of this token. */
+  int get end => span.end.offset;
 
   /** Returns the source text corresponding to this [Token]. */
-  String get text {
-    return source.text.substring(start, end);
-  }
+  String get text => span.text;
+
+  Token(this.kind, this.span);
 
   /** Returns a pretty representation of this token for error messages. **/
   String toString() {
     var kindText = TokenKind.kindToString(kind);
     var actualText = text;
     if (kindText != actualText) {
       if (actualText.length > 10) {
-        actualText = actualText.substring(0, 8) + '...';
+        actualText = '${actualText.substring(0, 8)}...';
       }
       return '$kindText($actualText)';
     } else {
       return kindText;
     }
   }
-
-  /** Returns a [SourceSpan] representing the source location. */
-  SourceSpan get span {
-    return new SourceSpan(source, start, end);
-  }
 }
 
 /** A token containing a parsed literal value. */
 class LiteralToken extends Token {
   var value;
-  LiteralToken(kind, source, start, end, this.value)
-      : super(kind, source, start, end);
+  LiteralToken(int kind, Span span, this.value) : super(kind, span);
 }
 
 /** A token containing error information. */
 class ErrorToken extends Token {
   String message;
-  ErrorToken(kind, source, start, end, this.message)
-      : super(kind, source, start, end);
+  ErrorToken(int kind, Span span, this.message) : super(kind, span);
 }