TypeScript Signal

Signal Pattern pattern written in Typescript.

Signals are typed and easy to use!

Installation

npm install signal-ts

Usage

Creating a Signal

Create an instance of Signal with the specified type, i.e, string, number, etc.

import {Signal} from "signal-ts";

let onCompleted: Signal<number> = new Signal();

Add function callback

Register a callback with add().

onCompleted.add((n: number) => {
	console.log("got a number", n);
});

You can also register a callback only once().

onCompleted.once(n: number) => {
	console.log("got a number once", n);
});

Emitting a Signal

onCompleted.emit(299792458);

Pro-Tips

Organize your events in a module or namespace.

export namespace Event {
	export const onLoaded: Signal<string> = new Signal();
	export const onCompleted: Signal<number> = new Signal();
}

Bind to events in your constructor.

class Receiver {
	private message: string;

	constructor() {
		Event.onLoaded.add(this.loaded);
	}
	public loaded(message: string): void {
		this.message = message;
	}
}

Remove a callback

Event.onLoaded.remove(this.callback);

License

MIT License