unlatch method

void unlatch([ T? partialResult ])

Opens the latch, notifying all listeners with the last cached value.

This method signals that the awaited task is complete. It will throw a StateError if called more than once before a reset.

partialResult: An optional result to provide at the moment of unlatching. If provided, it is used. Otherwise, the last value from fire is used.

Implementation

void unlatch([T? partialResult]) {
  if (_latchOpened) {
    throw StateError('Cannot unlatch() after latch is already complete');
  }

  _latchOpened = true;

  final result = partialResult ?? _cached;
  if (result == null) {
    throw StateError('Latch completed but no result was ever set!');
  }
  super.properties[this._property] = _cached;
}