TypeScript port of AS3 Signals.

Usage no npm install needed!

<script type="module">
  import robotlegsjsSignals from 'https://cdn.skypack.dev/@robotlegsjs/signals';



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SignalsJS is a TypeScript port of AS3 Signals. 15KB compressed.


Signals are light-weight, strongly-typed messaging tools. Wire your application with better APIs and less boilerplate than normal event systems.


  • A Signal is essentially a mini-dispatcher specific to one event, with its own array of listeners.
  • A Signal gives an event a concrete membership in a class.
  • Listeners subscribe to real objects, not to string-based channels.
  • Event string constants are no longer needed.
  • Signals was originally implemented by Robert Penner in AS3.
  • Signals are inspired by C# events and signals/slots in Qt.


// with DOM EventListener
button.addEventListener("click", onClick);

// Signal equivalent; past tense is recommended


You can get the latest release and the type definitions using NPM:

npm install @robotlegsjs/signals

Or using Yarn:

yarn add @robotlegsjs/signals


import { Signal } from "@robotlegsjs/signals";

let signal = new Signal();

signal.add(data => {

signal.dispatch({ message: "hello signal!" });

SignalsJS for enterprise

Available as part of the Tidelift Subscription

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