Streams

A normal Store can own external stream subscriptions with listenTo(...).

class LiveMessagesStore extends Store<List<Message>> {
  LiveMessagesStore(Stream<List<Message>> messages) : super(const []) {
    listenTo(
      messages,
      onData: commit,
      onError: (error, stackTrace) {
        effect(StreamFailed(error));
      },
    );
  }
}

Popsicle does not require a separate Stream Store hierarchy:

External Stream
      ↓
   listenTo
      ↓
    Store
      ↓
   commit
      ↓
     .ui()

listenTo(...) supports:

onData
onError
onDone
cancelOnError

It returns the underlying StreamSubscription<T> so a Store can pause, resume, or cancel early when needed.

Subscriptions registered through listenTo(...) are cancelled automatically when the Store is disposed. Their lifetime therefore follows the Store, not an individual widget build.