anchor.diff: -// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
  +// Copyright (c) 2013, 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.
   
  
positive.code:  * It returns the escaped string.
   */
  String encodeUriComponent(String component) {
    return _uriEncode(
      "-_.!~*'()0123456789"
      "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz", component);
  }
  
  /**
  
negative.code:  * It returns the escaped URI.
   */
  String encodeUri(String uri) {
    // Bit vector of 128 bits where each bit indicate whether a
    // character code on the 0-127 needs to be escaped or not.
    const canonicalTable = const [
                  //             LSB            MSB
                  //              |              |
        0x0000,   // 0x00 - 0x0f  0000000000000000
        0x0000,   // 0x10 - 0x1f  0000000000000000
                  //               ! #$ &'()*+,-./
        0xf7da,   // 0x20 - 0x2f  0101101111101111
                  //              0123456789:; = ?
        0xafff,   // 0x30 - 0x3f  1111111111110101
                  //              @ABCDEFGHIJKLMNO
        0xffff,   // 0x40 - 0x4f  1111111111111111
                  //              PQRSTUVWXYZ    _
        0x87ff,   // 0x50 - 0x5f  1111111111100001
                  //               abcdefghijklmno
        0xfffe,   // 0x60 - 0x6f  0111111111111111
                  //              pqrstuvwxyz   ~
        0x47ff];  // 0x70 - 0x7f  1111111111100010
    return _uriEncode(canonicalTable, uri);
  }
  
  /**
  