add method

T add(T updatedValue)

Implementation

T add(T updatedValue) {
  if (_controller.isClosed) {
    return _value;
  }

  if (!_hasEmitted) {
    _hasEmitted = true;
  }

  _prevValue = _value;
  _value = updatedValue;

  _controller.add((_prevValue, _value));
  return _value;
}