sophiebits/gist:8838019

## gistfile1.html
<!doctype html>
<html>
<head>
    <script src="http://cdnjs.cloudflare.com/ajax/libs/es5-shim/2.2.0/es5-shim.js"></script>
    <script src="http://cdnjs.cloudflare.com/ajax/libs/es5-shim/2.2.0/es5-sham.js"></script>
    <script src="http://fb.me/react-0.8.0.min.js"></script>
    <script src="http://fb.me/JSXTransformer-0.8.0.js"></script>
    <script type="text/jsx">
        /** @jsx React.DOM */
        var InputBox = React.createClass({
            onKeyUp: function(e){
                var value = this.refs.mask.getDOMNode().value.trim();
                this.refs.mask.getDOMNode().value = "-" + value;
            },
            render: function(){
                return (
                    <form>
                        <input type="text" placeholder="Something to mask"
                            ref="mask" onKeyUp={this.onKeyUp} />
                    </form>
                );
            }
        });

        React.renderComponent(
            <InputBox />,
            document.getElementById('content')
        );
    </script>
</head>
<body style="font-size: 1.5em">

    <h1>Let's React</h1>
    <div id="content"></div>

</body>
</html>
	<!doctype html>
	<html>
	<head>
	<script src="http://cdnjs.cloudflare.com/ajax/libs/es5-shim/2.2.0/es5-shim.js"></script>
	<script src="http://cdnjs.cloudflare.com/ajax/libs/es5-shim/2.2.0/es5-sham.js"></script>
	<script src="http://fb.me/react-0.8.0.min.js"></script>
	<script src="http://fb.me/JSXTransformer-0.8.0.js"></script>
	<script type="text/jsx">
	/** @jsx React.DOM */
	var InputBox = React.createClass({
	onKeyUp: function(e){
	var value = this.refs.mask.getDOMNode().value.trim();
	this.refs.mask.getDOMNode().value = "-" + value;
	},
	render: function(){
	return (
	<form>
	<input type="text" placeholder="Something to mask"
	ref="mask" onKeyUp={this.onKeyUp} />
	</form>
	);
	}
	});

	React.renderComponent(
	<InputBox />,
	document.getElementById('content')
	);
	</script>
	</head>
	<body style="font-size: 1.5em">

	<h1>Let's React</h1>
	<div id="content"></div>

	</body>
	</html>