React Base Fiddle (JSX)

Starting point for creating JSFiddles with React.

HTML

<script src="https://unpkg.com/react@16/umd/react.development.js"></script>
<script src="https://unpkg.com/react-dom@16/umd/react-dom.development.js"></script>
<div id="container">
    <!-- This element's contents will be replaced with your component. -->
</div>

Babel + JSX

class App extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      cityInput: "",
      requestHistory: [],
      weatherHistory: []
    };
  }
  async componentDidMount() {
    await this.getLocalLocation();
  }
  getLocalLocation() {
    return navigator.geolocation.getCurrentPosition(pos => {
      this.setState({
        requestHistory: this.state.requestHistory.concat([{
          lat: pos.coords.latitude,
          lon: pos.coords.longitude
        }])
      });
    });
  }
  render() {
    return (
      <div className="App">
        {JSON.stringify(this.state.requestHistory)}
      </div>
    );
  }
}

ReactDOM.render(
  <App />,
  document.getElementById('container')
);