stream method

Implementation

@override
Stream<T> stream() async* {
  if (_consumed) throw StateError('Receiver.stream() is single-subscription');
  _consumed = true;

  while (true) {
    switch (await _core.recv()) {
      case RecvOk<T>(value: final v):
        yield v;
      case RecvError():
        return;
    }
  }
}