# Await Event
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A really stupid utility I use frequently for event emitters.
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Allows you to `yield` an event and return the results.
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I use this a lot of locking.
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Note: you probably shouldn't use this for the `error` event.
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## Example
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```js
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var PassThrough = require('stream').PassThrough
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var stream = new PassThrough()
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// you attach it directly on an event emitter
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stream.await = require('await-event')
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co(function* () {
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var chunk = yield stream.await('data')
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var chunk = yield stream.await('data')
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var chunk = yield stream.await('data')
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}).catch(noop)
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stream.write('some chunk')
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```
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You can use awaitEvent without attach on an event emitter:
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```js
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var EventEmitter = require('event')
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var emitter = new EventEmitter()
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co(function*() {
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yield awaitEvent(emitter, 'ready')
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}).catch(noop)
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```
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When use this for `error` event, it will reject once `error` event emitted:
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```js
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var EventEmitter = require('event')
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var emitter = new EventEmitter()
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co(function*() {
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// it will throw when `error` event emitted
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yield awaitEvent(emitter, 'error')
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}).catch(err => console.error(err.stack))
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```
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