return the first event in a set of ee/event pairs
npm install ee-first[![NPM version][npm-image]][npm-url]
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Get the first event in a set of event emitters and event pairs,
then clean up after itself.
``sh`
$ npm install ee-first
`js`
var first = require('ee-first')
Invoke listener on the first event from the list specified in arr. arr is[ee, ...event]
an array of arrays, with each array in the format . listener
will be called only once, the first time any of the given events are emitted. If is one of the listened events, then if that fires first, the listener
will be given the argument.
The listener is invoked as listener(err, ee, event, args), where err is theerror
first argument emitted from an event, if applicable; ee is the eventevent
emitter that fired; 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
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[travis-url]: https://travis-ci.org/jonathanong/ee-first
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[coveralls-url]: https://coveralls.io/r/jonathanong/ee-first?branch=master
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[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
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[gittip-url]: https://www.gittip.com/jonathanong/