Kucukkanat's Emitter

Table of Contents

- Install
- Usage
- Examples & Demos
- API
- Contribute
- License

Install

This project uses node and npm. Go check them out if you don't have them locally installed.

``sh
$ npm install --save subscribe
`


`javascript
// using ES6 modules
import { Emitter } from 'subscribe'

// using CommonJS modules
var { Emitter } = require('subscribe')
`

The UMD build is also available on unpkg:

`html

`

You can find the library on window.__Emitter__.

Usage

`js
import {Emitter} from 'subscribe'
// OR
const {Emitter} = require('subscribe')

const eventbus = new Emitter()

// listen to an event
eventbus.on('foo', e => console.log('foo', e) )

// listen to all events
// This will fire first the 'type' event if it exists
eventbus.on('*', (type, e) => console.log(type, e) )

// fire an event
eventbus.emit('foo', { a: 'b' })

// working with handler references:
function onFoo() {}
eventbus.on('foo', onFoo) // listen
eventbus.off('foo', onFoo) // unlisten

// remove all listeners for specific event
eventbus.off('foo')

// Fire event listener only once
eventbus.once('knock knock', (data) => console.log("I will be fired only once"))
eventbus.emit('knock knock', null)
// This will not fire
eventbus.emit('knock knock', null)
`

Typescript

For better autocompletion Emitter class takes parameters for possible event names :

`js
import {Emitter} from 'subscribe'
const emitter = new Emitter<'foo' | 'bar'>()
emitter.on('foo', e => console.log('foo', e) )
emitter.on('bar', e => console.log('foo', e) )
// Will throw an error: (on typescript typecheck NOT ON RUNTIME!)
emitter.on('bar2', e => console.log('foo', e) )
`

*

API

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* [constructor][1]
* [Parameters][2]
* [on][3]
* [Parameters][4]
* [off][5]
* [Parameters][6]
* [emit][7]
* [Parameters][8]

constructor

Use the constructor to initiate the eventbus with handlers

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*
* listeners EventHandlerMap

on

Register an event handler for the given type.

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type [String][9] Type of event to listen for, or "" for all events
* handler [Function][10] Function to call in response to given event

off

Remove an event handler for the given type.

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type [String][9] Type of event to unregister handler from, or ""
* handler [Function][10] Handler function to remove

emit

Invoke this.listeners handlers for the given type.
If present, "*" handlers are invoked after type-matched handlers.

Note: Manually firing "\*" handlers is not supported.

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* type [String][9] The event type to invoke
* evt` Any? Any value (object is recommended and powerful), passed to each handler

[1]: #constructor

[2]: #parameters

[3]: #on

[4]: #parameters-1

[5]: #off

[6]: #parameters-2

[7]: #emit

[8]: #parameters-3

[9]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String

[10]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/function

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Found a problem? Want a new feature? First of all see if your issue or idea has already been reported.
If don't, just open a new clear and descriptive issue.

License

MIT License © Kucukkanat