mini-signals

mini-signals

signals, in JavaScript, fast

Description

Custom event/messaging system for TypeScript/JavaScript inspired by js-signals originally based on EventEmitter3 code base.

There are several advantages to signals over event-emitters (see Comparison between different Observer Pattern implementations). However, the current implementation of js-signals is (arguably) slow compared to other implementations (see EventsSpeedTests). mini-signals is a fast, minimal emitter, with an API similar to js-signals.

Note: Signals here are the type defined by js-signals inspired by AS3-Signals. They should not to be confused with SolidJS or Angular signals.

Install

npm:

npm install mini-signals

Example Usage

import { MiniSignal } from "mini-signals";

const mySignal = new MiniSignal<[string, string]>();

const binding = mySignal.add(onSignal); //add listener

mySignal.dispatch("foo", "bar"); // dispatch signal passing custom parameters
binding.detach(); // remove a single listener

function onSignal(foo: string, bar: string) {
  assert(foo === "foo");
  assert(bar === "bar");
}

Another Example

const myObject = {
  foo: "bar",
  updated: new MiniSignal<never>(),
};

myObject.updated.add(onUpdated, myObject); //add listener with context

myObject.foo = "baz";
myObject.updated.dispatch(); //dispatch signal

function onUpdated() {
  assert(this === myObject);
  assert(this.foo === "baz");
}

API

See API.md

License

Copyright (c) 2015-2023 Jayson Harshbarger

MIT License