anchor.diff:      return _controller.stream;
     }
   
  +  /**
  +   * Callback for receiving and processing bytes.
  +   * Supports segmented transfers, such as TCP buffers.
  +   */
     void _onData(List<int> bytes) {
   
       for (int offset = 0; offset < bytes.length; offset++) {
  
positive.code: part of esl;
  
  /**
   *
   */
  class PacketTransformer implements StreamTransformer<List<int>, Packet> {
    final StreamController<Packet> _controller = new StreamController<Packet>();
  
negative.code:               List<String> keyValuePair = headerLine.split(':');
  
                if (keyValuePair.length == 2) {
                  _currentPacket.addHeader(keyValuePair[0].trim(),
                                           keyValuePair[1].trim());
                } else {
                  this._controller.addError
                    (new StateError ('Skipping invalid buffer: "${headerLine}"'));
                }
              }
            }
  