Scoped view: topics on a named channel are invisible to other channels
Unsubscribe everything registered through this facade and its channels
Deliver payload synchronously to current subscribers of topic
Optionalpayload: TRegister the single responder for a topic. A second handle() on the same topic throws BUS_HANDLER_EXISTS; the returned unsubscribe frees the topic.
Subscribe to a topic; returns an unsubscribe function
Optionaloptions: SubscribeOptionsSubscribe for a single delivery (self-filtered emits don't consume it)
Optionaloptions: SubscribeOptionsSend a request; resolves with the handler's response, rejects with the handler's error. Waits up to options.timeout for a handler to appear (late-loading FynApps are normal), then rejects with BUS_REQUEST_TIMEOUT. options.signal stops the wait at any point (BUS_REQUEST_ABORTED); an already-invoking handler still runs, its result discarded.
Optionalpayload: TReqOptionaloptions: RequestOptions
Per-source view of the bus. Stamps meta.source on emits, filters self-echo by default, and tracks subscriptions so dispose() can remove them all.
A closure rather than a class:
source,channelNameand the shared subscription state are read on nearly every call, and as closure variables they cost one character each instead of a property lookup per use. Channel views are made by calling the factory again with the owning facade's state, so dispose() still covers them.