Object-Oriented / Patterns

Custom Event Emitter

mediumJS / TS

Problem Statement

Design an `EventEmitter` class with `subscribe(eventName, callback)` and `emit(eventName, args)` methods. `subscribe` should return an unsubscribe handle object with an `unsubscribe()` method.

Examples

Example:
const emitter = new EventEmitter();
const sub = emitter.subscribe('onClick', (x) => console.log(x));
emitter.emit('onClick', [42]); // prints 42
sub.unsubscribe();

Includes TypeScript & JavaScript starter code

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