React Contextual Component

app.jsx

// https://codesandbox.io/s/kxzwolv9k7


import React, { Component } from 'react';
import { render } from 'react-dom';

class Ember extends Component {
  constructor(props) {
    super(props);
    this.state = { isCool: 'yasss' };
  }

  render() {
    const content = this.props.children({
      isCool: this.state.isCool
    });

    return (
      <div>{content}</div>
    );
  }
}

const App = () =>
  <Ember>
    {
      ({ isCool }) =>
      <div>
        Ember is cool? {isCool}
      </div>
    }
  </Ember>;

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