code: function (match) {
              var lengthOfMatchedString = match[_GPF_START].length, charAfterValue = this._content.charAt(lengthOfMatchedString);
              if (charAfterValue) {
                  _gpfAssert(charAfterValue === this._separator, "Positive lookahead works");
                  return this._nextValue(++lengthOfMatchedString);
              }
              delete this._content;
              return false;    // No value means end of content
          }
docs: Check what appears after the extracted value
  
  @param {Object} match Regular expression match
  @return {Boolean} True if some remaining content must be parsed
  @since 0.2.3