# EE First

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Get the first event in a set of event emitters and event pairs, then clean up after itself.

## Install

```
$ 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()
```


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