# `ts-event-emitter` (yet another) event emitter written in typescript 😔
## Installation ```sh # install via npm... npm install @dominicstop/ts-event-emitter # or install via yarn. yarn add @dominicstop/ts-event-emitter ```
## Usage ### Basic Usage ```typescript type EventKeys = 'Foo' | 'Baz'; export const emitter: TSEventEmitter = new TSEventEmitter(); emitter.once('Foo', (event) => { console.log(event) }); emitter.emit('Foo', 'hello world'); emitter.once('Baz', (event) => { console.log(event?.age) }); emitter.emit('Baz', { age: 23 }); ``` ### In-Depth Usage ```typescript // 1. Create a string enum... enum Events { Foo = 'Foo', Bar = 'Bar', Baz = 'Baz' }; // 1.1. ...or alt., a union of strings (whichever you prefer). type EventKeys = 'Foo' | 'Bar' | 'Baz'; // 2. Create the emitter + event map... // * For each key in the event enum, define the type of the // `event` argument that the listener will receive. // * As mentioned in 1.1. you can also use the `EventKeys` union // in place of the `Events` enum. export const emitter: TSEventEmitter = new TSEventEmitter(); // 3.1. `event` arg. will be inferred as `(event: { name: string }) => void` emitter.once('Foo', (event) => { console.log(event.name) }); // 3.2.`event` arg. will be inferred as `() => void` // * Note: If you try to add an event param, TS produces an error. emitter.once('Bar', () => { /** no-op */ }); // 3.3. `event` will be inferred as // `(event: { age: number } | null) => void`. // * As such, we need to use the optional chaining operator to access `event`. emitter.once(Events.Baz, (event) => { console.log(event?.age) }); // 4. Next, lets broadcast some events. emitter.emit(Events.Foo, { name: 'd'}); emitter.emit('Baz', { age: 1 }); // 4.1. Note: You can't pass a data argument with the 'Bar' event // because in step 2.2., the event object is defined as `null`. emitter.emit('Bar'); // 4.2. We must explicitly pass a null/undefined value for the data // argument since it can be optional (e.g. step 2.3.) emitter.emit('Baz', null); ``` ## Documentation ### `TSEvenEmitter` | Property/Method | Description | | ------------------------------------------------------------ | ----------- | | 🔤 `addListener`

⚛️ `(eventKey, listener) => { unsubscribe: () => void }` | | | 🔤 `removeListener`

⚛️ `(eventKey, listenerToRemove) => void` | | | 🔤 `once`

⚛️ `(eventKey, listener) => void` | | | 🔤 `removeAllListeners`

⚛️ `() => void` | | | 🔤 `emit`

⚛️ `(eventKey, data) => void` | |

c	File Name	Size	files	T	Date
zip	lib/	17247	12	---	2025-07-03 11:57:32
zip	src/	4168	2	---	2025-10-15 10:09:14
-	LICENSE	1067		%	2025-10-15 10:07:37
-	README.md	3264		md	2025-10-15 10:07:37
-	package.json	1676		json	2025-10-15 10:07:37

🌲 / linkwarden node_modules @dominicstop ts-event-emitter

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