ActorRef; sending messages to it will emit them on the stream.
ActorRef, sending messages to it will emit them on the stream. The actor contains a buffer but since communication is one way, there is no back pressure. Handling overflow is done by either dropping elements or failing the stream; the strategy is chosen by the user.
emits when there is demand and there are messages in the buffer or a message is sent to the
completes when the
ActorRef is sent