anchor.diff:    // TIMEOUT when waiting for a pending op to come back from the server.
     static const PENDING_OP_TIMEOUT = const Duration(seconds: 3);
   
  -  //
     bool _bindPending = false;
   
     // true if a BIND is pending
  
positive.code:   }
  
    // Process a generic LDAP operation.
    Future<LDAPResult> process(RequestOp rop) {
      var m = new LDAPMessage(++_nextMessageId, rop);
      var op = new _FuturePendingOp(m);
      _queueOp(op);
      return op.completer.future;
    }
  
    _queueOp(_PendingOp op) {
  
negative.code: // A pending opertion that expects a single return response message
  // returned via a future. For all LDAP ops except search results
  class _FuturePendingOp extends _PendingOp {
    Completer completer = new Completer();
  
    _FuturePendingOp(LDAPMessage m) : super(m);
  
  