code: func (tr TimerResult) Incomplete() bool {
  	switch tr.Err {
  	case nil:
  		return false
  	case context.Canceled, context.DeadlineExceeded:
  		return true
  	default:
  		panic(fmt.Errorf("unknown TimerResult error value: %v", tr.Err))
  	}
  }
docs: // Incomplete will return true if the timer result indicates that the timer
  // operation was canceled prematurely due to Context cancellation or deadline
  // expiration.