// (C) 2008 Google Inc.
var jsonParse = (function () {
  var number
      = '(?:-?\\b(?:0|[1-9][0-9]*)(?:\\.[0-9]+)?(?:[eE][+-]?[0-9]+)?\\b)';
  var oneChar = '(?:[^\\0-\\x08\\x0a-\\x1f\"\\\\]'
      + '|\\\\(?:[\"/\\\\bfnrt]|u[0-9A-Fa-f]{4}))';
  var string = '(?:\"' + oneChar + '*\")';
  var jsonToken = new RegExp(
      '(?:false|true|null|[\\{\\}\\[\\]]'
      + '|' + number
      + '|' + string
      + ')', 'g');
  var escapeSequence = new RegExp('\\\\(?:([^u])|u(.{4}))', 'g');
  var escapes = {
    '"': '"',
    '/': '/',
    '\\': '\\',
    'b': '\b',
    'f': '\f',
    'n': '\n',
    'r': '\r',
    't': '\t'
  };
  function unescapeOne(_, ch, hex) {
    return ch ? escapes[ch] : String.fromCharCode(parseInt(hex, 16));
  }
  var EMPTY_STRING = new String('');
  var SLASH = '\\';
  var firstTokenCtors = { '{': Object, '[': Array };

  return function (json) {
    var toks = json.match(jsonToken);
    var result;
    var tok = toks[0];
    if ('{' === tok) {
      result = {};
    } else if ('[' === tok) {
      result = [];
    } else {
      throw new Error(tok);
    }

    var key;
    var stack = [result];
    for (var i = 1, n = toks.length; i < n; ++i) {
      tok = toks[i];

      var cont;
      switch (tok.charCodeAt(0)) {
        default:
          cont = stack[0];
          cont[key || cont.length] = +(tok);
          key = void 0;
          break;
        case 0x22:
          tok = tok.substring(1, tok.length - 1);
          if (tok.indexOf(SLASH) !== -1) {
            tok = tok.replace(escapeSequence, unescapeOne);
          }
          cont = stack[0];
          if (!key) {
            if (cont instanceof Array) {
              key = cont.length;
            } else {
              key = tok || EMPTY_STRING;
              break;
            }
          }
          cont[key] = tok;
          key = void 0;
          break;
        case 0x5b:
          cont = stack[0];
          stack.unshift(cont[key || cont.length] = []);
          key = void 0;
          break;
        case 0x5d:
          stack.shift();
          break;
        case 0x66:
          cont = stack[0];
          cont[key || cont.length] = false;
          key = void 0;
          break;
        case 0x6e:
          cont = stack[0];
          cont[key || cont.length] = null;
          key = void 0;
          break;
        case 0x74:
          cont = stack[0];
          cont[key || cont.length] = true;
          key = void 0;
          break;
        case 0x7b:
          cont = stack[0];
          stack.unshift(cont[key || cont.length] = {});
          key = void 0;
          break;
        case 0x7d:
          stack.shift();
          break;
      }
    }
    if (stack.length) { throw new Error(); }
    return result;
  };
})();