anchor.diff:    if (verbose) {
       print("sending: '${json.stringify(cmd)}'");
     }
  -  vmStream.writeString(json.stringify(cmd));
  +  vmSock.addString(json.stringify(cmd));
     return completer.future;
   }
   
  
positive.code: 
  
  void quitShell() {
    vmStream.close();
    vmSock.close();
    stdin.close();
  }
  
negative.code: 
  void debuggerMain() {
    outstandingCommands = new Map<int, Completer>();
    Socket.connect("127.0.0.1", 5858).then((s) {
      vmSock = s;
      Stream<String> stringStream = vmSock.transform(new StringDecoder());
      streamSubscription = stringStream.listen(
          (String data) {
            processVmData(data);
          },
          onDone: () {
            print("VM debugger connection closed");
            quitShell();
          },
          onError: (err) {
            print("Error in debug connection: $err");
            quitShell();
          });
      stdin.transform(new StringDecoder())
          .transform(new LineTransformer())
          .listen((String line) => processCommand(line));
    });
  }
  
  void main() {
  