React Base Fiddle (JSX)

Starting point for creating JSFiddles with React. This uses React with Addons.

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/babel-core/5.8.24/browser.js"></script>
<script src="https://fb.me/react-with-addons-0.14.6.js"></script>
<script src="https://fb.me/react-dom-0.14.6.js"></script>
<script src="https://facebook.github.io/react/js/jsfiddle-integration-babel.js"></script>

<div id="container">
</div>

JavaScript 1.7

var Hello = React.createClass({
  componentWillReceiveProps: function(nextProps) {
  	var total = 0;
    this.props.vals.forEach(val => total+= val);
    
    var nextTotal = 0;
    nextProps.vals.forEach(val => nextTotal+= val);
    
		console.log(total, nextTotal)
  },
  render: function() {
  	var total = 0;
    vals.forEach(val => total+= val)
    return (
    	<div>{total}</div>
    )
  }
});

var vals = [1, 21, 452, 123];

setInterval(renderReact, 1000)

function renderReact() {
	vals.push(10);
  ReactDOM.render(
    <Hello
      vals={vals}
    />,
    document.getElementById('container')
  );
}