anchor.diff:      });
       _socket.onClose.listen((event) {
         if (onClose != null) onClose();
  -    }); 
  +    });
   
     }
   
  
positive.code: 
  SockJS.Client _socket;
  Future<StompClient> connect(String url, {
          String host, 
          String login, 
          String passcode, 
          List<int> heartbeat,
          List<String> protocolsWhiteList,
          void onDisconnect(),
          void onError(String message, String detail, [Map<String, String> headers]),
          void onConnectionError(error, stacktrace),
          bool debugFlag:false
        }) {
          Future<Object> waitingForConnection = _SockDartConnector.start(url, protocolsWhiteList, debugFlag);
  
          return waitingForConnection.then((connector){
               print("Got SockJS/SockDart connection");
              Future<StompClient> waitingForStompClientHolder = StompClient.connect(connector,
                  host: host,
                  login: login, 
                  passcode: passcode, 
                  heartbeat: heartbeat,
                  onDisconnect: onDisconnect,
                  onError: onError).catchError((e) {
  
negative.code:                   onConnectionError(e, e);
                  });
  
              return(waitingForStompClientHolder);
          });
  }
  
  