You can not select more than 25 topics
			Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
		
		
		
		
		
			
		
			
				
					81 lines
				
				2.6 KiB
			
		
		
			
		
	
	
					81 lines
				
				2.6 KiB
			| 
								 
											3 years ago
										 
									 | 
							
								# EE First
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								[![NPM version][npm-image]][npm-url]
							 | 
						||
| 
								 | 
							
								[![Build status][travis-image]][travis-url]
							 | 
						||
| 
								 | 
							
								[![Test coverage][coveralls-image]][coveralls-url]
							 | 
						||
| 
								 | 
							
								[![License][license-image]][license-url]
							 | 
						||
| 
								 | 
							
								[![Downloads][downloads-image]][downloads-url]
							 | 
						||
| 
								 | 
							
								[![Gittip][gittip-image]][gittip-url]
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								Get the first event in a set of event emitters and event pairs,
							 | 
						||
| 
								 | 
							
								then clean up after itself.
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								## Install
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								```sh
							 | 
						||
| 
								 | 
							
								$ npm install ee-first
							 | 
						||
| 
								 | 
							
								```
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								## API
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								```js
							 | 
						||
| 
								 | 
							
								var first = require('ee-first')
							 | 
						||
| 
								 | 
							
								```
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								### first(arr, listener)
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								Invoke `listener` on the first event from the list specified in `arr`. `arr` is
							 | 
						||
| 
								 | 
							
								an array of arrays, with each array in the format `[ee, ...event]`. `listener`
							 | 
						||
| 
								 | 
							
								will be called only once, the first time any of the given events are emitted. If
							 | 
						||
| 
								 | 
							
								`error` is one of the listened events, then if that fires first, the `listener`
							 | 
						||
| 
								 | 
							
								will be given the `err` argument.
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								The `listener` is invoked as `listener(err, ee, event, args)`, where `err` is the
							 | 
						||
| 
								 | 
							
								first argument emitted from an `error` event, if applicable; `ee` is the event
							 | 
						||
| 
								 | 
							
								emitter that fired; `event` is the string event name that fired; and `args` is an
							 | 
						||
| 
								 | 
							
								array of the arguments that were emitted on the event.
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								```js
							 | 
						||
| 
								 | 
							
								var ee1 = new EventEmitter()
							 | 
						||
| 
								 | 
							
								var ee2 = new EventEmitter()
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								first([
							 | 
						||
| 
								 | 
							
								  [ee1, 'close', 'end', 'error'],
							 | 
						||
| 
								 | 
							
								  [ee2, 'error']
							 | 
						||
| 
								 | 
							
								], function (err, ee, event, args) {
							 | 
						||
| 
								 | 
							
								  // listener invoked
							 | 
						||
| 
								 | 
							
								})
							 | 
						||
| 
								 | 
							
								```
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								#### .cancel()
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								The group of listeners can be cancelled before being invoked and have all the event
							 | 
						||
| 
								 | 
							
								listeners removed from the underlying event emitters.
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								```js
							 | 
						||
| 
								 | 
							
								var thunk = first([
							 | 
						||
| 
								 | 
							
								  [ee1, 'close', 'end', 'error'],
							 | 
						||
| 
								 | 
							
								  [ee2, 'error']
							 | 
						||
| 
								 | 
							
								], function (err, ee, event, args) {
							 | 
						||
| 
								 | 
							
								  // listener invoked
							 | 
						||
| 
								 | 
							
								})
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								// cancel and clean up
							 | 
						||
| 
								 | 
							
								thunk.cancel()
							 | 
						||
| 
								 | 
							
								```
							 | 
						||
| 
								 | 
							
								
							 | 
						||
| 
								 | 
							
								[npm-image]: https://img.shields.io/npm/v/ee-first.svg?style=flat-square
							 | 
						||
| 
								 | 
							
								[npm-url]: https://npmjs.org/package/ee-first
							 | 
						||
| 
								 | 
							
								[github-tag]: http://img.shields.io/github/tag/jonathanong/ee-first.svg?style=flat-square
							 | 
						||
| 
								 | 
							
								[github-url]: https://github.com/jonathanong/ee-first/tags
							 | 
						||
| 
								 | 
							
								[travis-image]: https://img.shields.io/travis/jonathanong/ee-first.svg?style=flat-square
							 | 
						||
| 
								 | 
							
								[travis-url]: https://travis-ci.org/jonathanong/ee-first
							 | 
						||
| 
								 | 
							
								[coveralls-image]: https://img.shields.io/coveralls/jonathanong/ee-first.svg?style=flat-square
							 | 
						||
| 
								 | 
							
								[coveralls-url]: https://coveralls.io/r/jonathanong/ee-first?branch=master
							 | 
						||
| 
								 | 
							
								[license-image]: http://img.shields.io/npm/l/ee-first.svg?style=flat-square
							 | 
						||
| 
								 | 
							
								[license-url]: LICENSE.md
							 | 
						||
| 
								 | 
							
								[downloads-image]: http://img.shields.io/npm/dm/ee-first.svg?style=flat-square
							 | 
						||
| 
								 | 
							
								[downloads-url]: https://npmjs.org/package/ee-first
							 | 
						||
| 
								 | 
							
								[gittip-image]: https://img.shields.io/gittip/jonathanong.svg?style=flat-square
							 | 
						||
| 
								 | 
							
								[gittip-url]: https://www.gittip.com/jonathanong/
							 |