anchor.diff:      property AsyncState: Object read fAsyncState;
       property IsFaulted: Boolean read fException <> nil;
       property IsCompleted: Boolean read fState = TaskState.Done; 
  -    method &Await(aCompletion: IAwaitCompletion): Boolean; // true = yield; false = long done
  +    method &Await(aCompletion: __ElementsIAwaitCompletion): Boolean; // true = yield; false = long done
   
       {$HIDE W38}
       method Wait; reintroduce;virtual;
  
positive.code:   fTask.Done(nil);
  end;
  
  method __ElementsTask.Await(aCompletion: IAwaitCompletion): Boolean;
  begin
    if IsCompleted then exit false;
    var q := __ElementsTask.ThreadSyncHelper.GetThreadContext;
  
negative.code:     method run; override; empty;
    end;
  
    __ElementsIAwaitCompletion = public interface
      method moveNext(aState: Object);
    end;
  
  