class Component extends React.Component {
  render(){
    return (
      <>
        <h1>Hello, {this.props.name}</h1>
        <h2>{this.props.loading ? 'Loading...' : this.props.children}</h2>
        <Clock/>
      </>
    )
  }
}

class Clock extends React.Component {
  constructor(props){
    super(props);

    this.state = {
         date: new Date()
    };
  }

  render(){
    return(
      <h1>{this.state.date.toLocaleTimeString()}</h1>
    )
  }
}


ReactDOM.render(
  <Component name="Adam" loading={false}>
    Test
  </Component>,
  document.getElementById("app")
)