Socket
Socket
Sign inDemoInstall

event-emitter

Package Overview
Dependencies
8
Maintainers
1
Versions
15
Alerts
File Explorer

Advanced tools

Install Socket

Protect your apps from supply chain attacks

Install

event-emitter

Environment agnostic event emitter

    0.3.5latest
    GitHub
    npm

Version published
Maintainers
1
Weekly downloads
5,441,343
increased by4.66%

Weekly downloads

Readme

Source

event-emitter

Environment agnostic event emitter

Installation

$ npm install event-emitter

To port it to Browser or any other (non CJS) environment, use your favorite CJS bundler. No favorite yet? Try: Browserify, Webmake or Webpack

Usage

var ee = require('event-emitter');

var MyClass = function () { /* .. */ };
ee(MyClass.prototype); // All instances of MyClass will expose event-emitter interface

var emitter = new MyClass(), listener;

emitter.on('test', listener = function (args) {
  // … react to 'test' event
});

emitter.once('test', function (args) {
  // … react to first 'test' event (invoked only once!)
});

emitter.emit('test', arg1, arg2/*…args*/); // Two above listeners invoked
emitter.emit('test', arg1, arg2/*…args*/); // Only first listener invoked

emitter.off('test', listener);              // Removed first listener
emitter.emit('test', arg1, arg2/*…args*/); // No listeners invoked

Additional utilities

allOff(obj) (event-emitter/all-off)

Removes all listeners from given event emitter object

hasListeners(obj[, name]) (event-emitter/has-listeners)

Whether object has some listeners attached to the object. When name is provided, it checks listeners for specific event name

var emitter = ee();
var hasListeners = require('event-emitter/has-listeners');
var listener = function () {};

hasListeners(emitter); // false

emitter.on('foo', listener);
hasListeners(emitter); // true
hasListeners(emitter, 'foo'); // true
hasListeners(emitter, 'bar'); // false

emitter.off('foo', listener);
hasListeners(emitter, 'foo'); // false
pipe(source, target[, emitMethodName]) (event-emitter/pipe)

Pipes all events from source emitter onto target emitter (all events from source emitter will be emitted also on target emitter, but not other way).
Returns pipe object which exposes pipe.close function. Invoke it to close configured pipe.
It works internally by redefinition of emit method, if in your interface this method is referenced differently, provide its name (or symbol) with third argument.

unify(emitter1, emitter2) (event-emitter/unify)

Unifies event handling for two objects. Events emitted on emitter1 would be also emitted on emitter2, and other way back.
Non reversible.

var eeUnify = require('event-emitter/unify');

var emitter1 = ee(), listener1, listener3;
var emitter2 = ee(), listener2, listener4;

emitter1.on('test', listener1 = function () { });
emitter2.on('test', listener2 = function () { });

emitter1.emit('test'); // Invoked listener1
emitter2.emit('test'); // Invoked listener2

var unify = eeUnify(emitter1, emitter2);

emitter1.emit('test'); // Invoked listener1 and listener2
emitter2.emit('test'); // Invoked listener1 and listener2

emitter1.on('test', listener3 = function () { });
emitter2.on('test', listener4 = function () { });

emitter1.emit('test'); // Invoked listener1, listener2, listener3 and listener4
emitter2.emit('test'); // Invoked listener1, listener2, listener3 and listener4

Tests Build Status

$ npm test

Keywords

FAQs

Last updated on 15 Mar 2017

Did you know?

Socket installs a GitHub app to automatically flag issues on every pull request and report the health of your dependencies. Find out what is inside your node modules and prevent malicious activity before you update the dependencies.

Install

Related posts

SocketSocket SOC 2 Logo

Product

  • Package Alerts
  • Integrations
  • Docs
  • Pricing
  • FAQ
  • Roadmap

Stay in touch

Get open source security insights delivered straight into your inbox.


  • Terms
  • Privacy
  • Security

Made with ⚡️ by Socket Inc