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://npmcdn.com/react@latest/dist/react-with-addons.js"></script>
<script src="https://npmcdn.com/react-dom@latest/dist/react-dom.js"></script>
<script src="https://facebook.github.io/react/js/jsfiddle-integration-babel.js"></script>

<div id="container">
    <!-- This element's contents will be replaced with your component. -->
</div>

JavaScript 1.7

var update = React.addons.update;

var Hello = React.createClass({
	getInitialState: function(){
  	return {
    		a: {
        	b: [{ c: '', d: ''}, {c: 'B', d: 'W'}]
        },
        otherProperty: 'randomProperty'
    }
  },
  change: function(){
  	let index = 0;
  	let newState = update(this.state, {
       a: {
       	 b: {
          [index]: {
                   c: { $set: "new value"}
           }
        }
      }
    })
    this.setState(newState, () => console.log(this.state))
  },
  render: function() {
    
    return <button onClick={this.change}>Click to change state (Check console.log)</button>;
  }
});

ReactDOM.render(
  <Hello name="World" />,
  document.getElementById('container')
);