Spaces:
Sleeping
Sleeping
# 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/ | |