class HelloWorld extends React.Component<{date: Date}, void> {
render() { return ( <p> Hello, <input type="text" placeholder="Your name here" />! It is {this.props.date.toTimeString()} </p> ); }
}
setInterval(function() {
ReactDOM.render( <HelloWorld date={new Date()} />, document.getElementById('example') );
}, 500);