sub-events
v1.10.1
Published
Lightweight, strongly-typed events, with monitored subscriptions.
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Strongly-Typed Events
Lightweight, strongly-typed events, with monitored subscriptions.
Install
npm i sub-events
Usage
- On event-provider side:
import {SubEvent} from 'sub-events';
// creating a strongly-typed event:
const e: SubEvent<string> = new SubEvent();
// triggering the event when needed:
e.emit('hello');
- On event-consumer side:
// subscribing to the event:
const sub = e.subscribe((data: string) => {
// data = 'hello'
});
// cancel the subscription when no longer needed:
sub.cancel();
API: Subscription, subscribe, cancel
Monitoring Subscriptions
Class SubEventCount extends SubEvent with event onCount, to observe the number of subscriptions:
import {SubEventCount, ISubCountChange} from 'sub-events';
// creating a strongly-typed event:
const e: SubEventCount<string> = new SubEventCount();
e.onCount.subscribe((info: ISubCountChange) => {
// number of subscriptions has changed;
// info = {newCount, prevCount}
});
// any subscription will trigger event onCount:
const sub = e.subscribe(data => {});
// cancelling a subscription will trigger onCount:
sub.cancel();
API: SubEventCount, onCount
Browser
When including directly from HTML, you can access all types under subEvents
namespace:
<script src="./node_modules/sub-events/dist"></script>
<script>
const e = new subEvents.SubEvent();
e.subscribe(data => {
// data received
});
</script>
Note that pre-built script includes only the core library, without the Extras, which you can bundle yourself as needed.