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                <div class="app"></div>


                body {
  font-family: sans-serif


                const { createElement, Component} = React
const h = createElement

const Bar = ({foo}) => <span>{foo}</span>

const withFooHOC = Render => props => <Render foo='foo' {...props} />

const BarWithFoo = withFooHOC(Bar)

const RenderWithFoo = ({render, ...props}) => render({...props, foo: 'foo'})

const RenderWithFooCE= ({render, ...props}) => h(render, {...props, foo: 'foo'})

const InjectWithFoo = ({Render, ...props}) => <Render {...props} foo={'foo'} />

const Demo = ({children, label, ...props}) => (<p><b>{label}</b> {children}</p>)

class App extends Component {
  constructor() {
    this.state = { renderCount: 0 }
  componentDidMount() {
    window.setInterval(() => {
      this.setState({renderCount: this.state.renderCount + 1})
    }, 1000)
  render () {
    const count = this.state.renderCount
    // Defining a fn here is same as defining inside the JSX below:
    const Inline = ({foo}) => <span>{foo}</span>
    return (
        <p>Render Count: {count}</p>
          Turn on "Paint Flashing" in Devtools > Rendering to see when components redraw.
        <Demo label='HOC'>
        <Demo label='Inline HOC'>
          { h(withFooHOC(Bar)) }
        <Demo label='Injected Component'>
          <InjectWithFoo Render={Bar} />
        <Demo label='Inline Injected Component'>
          <InjectWithFoo Render={Inline} />
        <Demo label='Render Prop with createElement'>
          <RenderWithFooCE render={Bar} />
        <Demo label='Inline Render Prop with createElement'>
          <RenderWithFooCE render={Inline} />
        <Demo label='Render Prop'>
          <RenderWithFoo render={Bar} />
        <Demo label='Inline Render Prop'>
          <RenderWithFoo render={Inline} />

ReactDOM.render(<App />, document.querySelector('.app'))