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# 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/
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