# when-dom-ready

> $(document).ready() for the 21st century

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Returns a Promise for cleaner usage, provides a Promise chain helper function and can also be used as a pure function.

## Install

```shell
npm install --save when-dom-ready
```

## Usage

```js
import whenDomReady from 'when-dom-ready';

whenDomReady()
  .then(() => console.log('DOM is ready yo!'));
```

You can still use callbacks if you want to:

```js
whenDomReady(() => console.log('DOM is ready yo!'));
```

## Promise chain helper

There is also a little helper function, `whenDomReady.resume()`, that pauses the execution of a Promise chain and then resumes it with the last value once the DOM is ready.

This allows you to specify complex async control flow in simple readable code:

```js
fetch('/my-badass-api.json')
  .then(getSomeProcessingDoneWhileWaitingForDom)
  .then(whenDomReady.resume())
  .then(injectDataIntoDom);
```

## Pure usage

You can make the function pure by passing in a `document` object. This is really [useful for tests](https://github.com/lukechilds/when-dom-ready/blob/master/test/unit.js) and mocking environments.

For example this works in Node.js:

```js
const jsdom = require('jsdom');
const whenDomReady = require('when-dom-ready');

const doc = jsdom.jsdom('').defaultView.document;

whenDomReady(doc)
  .then(() => console.log('DOM is ready yo!'));
```

Again, you can use the callback version as a pure function too:

```js
whenDomReady(() => console.log('DOM is ready yo!'), doc);
```

And of course the helper:

```js
//...
  .then(whenDomReady.resume(doc))
```

## License

MIT © Luke Childs