3h-event

A well-typed event emitter.

Usage no npm install needed!

<script type="module">
  import hEvent from 'https://cdn.skypack.dev/3h-event';
</script>

README

3h-event

A well-typed event emitter.

Links

Example

import { Event, EventEmitter } from '3h-event';

const EVENT_B = Symbol('name of event b');

type EventA = Event<'name_of_event_a', DataTypeOfEventA>;
type EventB = Event<EVENT_B, DataTypeOfEventB>;

interface MyEvents {
    name_of_event_a: EventA;
    [EVENT_B]: EventB;
}

const eventEmitter = new EventEmitter<MyEvent>();

eventEmitter.on('name_of_event_a', (event) => {
    event.stop();
    // ...
});

eventEmitter.on(EVENT_B, (event) => {
    event.cancel();
    // ...
});

const eventA: EventA = new Event({
    name: 'name_of_event_a',
    data: dataA,
    stoppable: true,
});

eventEmitter.emit(eventA);

if (eventA.stopped) {
    // ...
}

const eventB: EventB = new Event({
    name: EVENT_B,
    data: dataB,
    cancelable: true,
});

eventEmitter.emit(eventB);

if (eventB.canceled) {
    // ...
}