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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              html, body {
  height: 100%;

Expandable component receives Header and Content as COMPONENT PROPS *o* (known as Component Injection)

 - Very obvious in render method that Expandable is wrapping this CustomExpandable component
 - Looks most "composable"
 - Should work very well with component prop types
 - Fairly nice namespacing
 - Enforces structure at the Expandable level, rather than the custom implementation

 - Maybe not as customisable? ie: if I want Content to render before Header, I can't. NOTE: could be mitigated with a renderProp ;)
 - You have to write out separate components for each prop (is this even a con?)

Read more: 
- Intro to this concept


class Expandable extends React.PureComponent {
  constructor(props) {
    this.state = {
      isOpen: false
  toggleOpen = () => {
    this.setState({ isOpen: !this.state.isOpen })
  render() {
    const { isOpen } = this.state
    const { 
    } = this.props
    const propsForInjectedComponents = {
      isOpen: isOpen,
      toggleOpen: this.toggleOpen,
    // TODO: maybe check for a props.render() here, if it exists, render that instead!

    return (
        <button onClick={this.toggleOpen}>
          <Header {...propsForInjectedComponents} />
        {isOpen && <Content {...propsForInjectedComponents} />}

class CustomExpandable extends React.Component {
  ExpandableHeader = (isOpen, toggleOpen) => (
    <span>Click me</span>
  // Pass isOpen and toggleOpen if needed
  ExpandableContent = (isOpen, toggleOpen) => (
  render() {
    return (

/** ==================================================================================== **/

class App extends React.Component {
  render() {
    return (
      <CustomExpandable />

  <App />
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