Function constructor

examples/00 Chessboard/Tutorial App/index.js:9–12

(props)

 */
export default class ChessboardTutorialApp extends Component {
  constructor(props) {
    super(props);
    this.unobserve = observe(this.handleChange.bind(this));
  }

  handleChange(knightPosition) {
    const nextState = { knightPosition };