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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/