@garzj/event-subscriber v2.1.0

@garzj/event-subscriber

Proxies subscriptions to an EventEmitter and stores references, allowing for an easy removal.

Features

• TypeScript support
• Compatible with
  • EventTarget
  • EventEmitter
  • typed-emitter
  • tiny-typed-emitter
  • more...

Heads up

Due to a TypeScript limitation (there does not seem to be a reliable way to remap return types of function overloads), methods of the EventSubscriber class may look like they return the original event emitter (they do not, the subscriber is returned).

It's probably better to avoid chaines like .on(a, b).on(c, d) and prefer sub.on(a, b); sub.on(c, d); instead.

Installation

npm i @garzj/event-subscriber

or with yarn

yarn add @garzj/event-subscriber

Usage

Subscribe to events

import { EventEmitter } from 'events';
import { EventSubscriber } from '@garzj/event-subscriber';

const myEmitter = new EventEmitter();

myEmitter.on('my-event', () => console.log('Always called!'));
myEmitter.emit('my-event');

const sub = new EventSubscriber(myEmitter);
sub.on('my-event', () => console.log('Temporarily called!'));
myEmitter.emit('my-event');
sub.off();

myEmitter.emit('my-event');

Output

Always called!
Always called!
Temporarily called!
Always called!

Forward type decleration

import { EventSubscriber } from '@garzj/event-subscriber';

let subscriber: EventSubscriber<typeof process>;

subscriber = new EventSubscriber(process);
subscriber.on('exit', () => console.log('process exit'));
subscriber.off();