@sellside/emitter

emitter

Event emitter for node.js projects.

Please consider following this project's author, Jon Schlinkert, and consider starring the project to show your ❤️ and support.

Install

Install with npm:

$ npm install --save @sellside/emitter

Attribution

This is based on component-emitter, with some changes and a couple of new methods. That project seems to no longer be maintained.

Usage

Add to your node.js project with the following line of code:

var Emitter = require('@sellside/emitter');

API

Emitter

Initialize a new Emitter.

Example

const Emitter = require('emitter');
// as an `Emitter` instance
const emitter = new Emitter;
emitter.emit('something');
// or inherit
class MyEmitter extends Emitter {}

Emitter#mixin

Mixin methods from Emitter.

Params

• obj {Object}
• returns {Object}

Example

const Emitter = require('emitter');
const obj = {};
Emitter.mixin(obj);
obj.on('status', console.log);
obj.emit('status', 'I emit!');

.listeners

Return the array of registered listeners for event.

Params

• event {String}
• returns {Array}

Example

// all listeners for event "status"
console.log(emitter.listeners('status'));
// all listeners
console.log(emitter.listeners());

.on

Listen on the given event with fn.

Params

• event {String}
• fn {Function}
• returns {Emitter}

Example

emitter.on('foo', () => 'do stuff');

.once

Adds an event listener that will be invoked a single time then automatically removed.

Params

• event {String}
• fn {Function}
• returns {Emitter}

Example

emitter.only('once', () => 'do stuff');

.only

Ensures that listeners for event are only registered once and are disabled correctly when specified. This is different from .once, which only emits once.

Params

• event {String}
• options {Object}
• fn {Function}
• returns {Emitter}

Example

emitter.only('foo', () => 'do stuff');

.off

Remove the given listener for event, or remove all registered listeners if event is undefined.

Params

• event {String}
• fn {Function}
• returns {Emitter}

Example

emitter.off();
emitter.off('foo');
emitter.off('foo', fn);

.has

Returns true if the emitter has registered listeners for event.

Params

• event {String}
• returns {Boolean}

Example

emitter.on('foo', 'do stuff');
console.log(emitter.has('foo')); // true
console.log(emitter.has('bar')); // false

About

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.

Please read the contributing guide for advice on opening issues, pull requests, and coding standards.

Running Tests

Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command:

$ npm install && npm test

Building docs

(This project's readme.md is generated by verb, please don't edit the readme directly. Any changes to the readme must be made in the .verb.md readme template.)

To generate the readme, run the following command:

$ npm install -g verbose/verb#dev verb-generate-readme && verb

Related projects

You might also be interested in these projects:

• breakdance: Breakdance is a node.js library for converting HTML to markdown. Highly pluggable, flexible and easy… more | homepage
• micromatch: Glob matching for javascript/node.js. A drop-in replacement and faster alternative to minimatch and multimatch. | homepage
• snapdragon: Easy-to-use plugin system for creating powerful, fast and versatile parsers and compilers, with built-in source-map… more | homepage

Author

Jon Schlinkert

• linkedin/in/jonschlinkert
• github/jonschlinkert
• twitter/jonschlinkert

License

Copyright © 2017, Jon Schlinkert. Released under the MIT License.

---

This file was generated by verb-generate-readme, v0.6.0, on December 04, 2017.