text: import React from 'react';
  import ReactDOM from 'react-dom';
  import './index.css';
  import Clock from './App';
  import Button from './Button';
  import * as serviceWorker from './serviceWorker';
  
  class App extends React.Component {
    render(){
      return(
        <div className="wrapper">
          <Clock />
          <Button />
        </div>
      )
    };
  }
  
  
  ReactDOM.render(<App />, document.getElementById('root'));
  
  
  
  
  
  
  
  
  // function Greet() {
  //    let phrase = 'world!';
  //   return (
  //     <h1>Hello {phrase} {4 + 4}</h1>
  //   )
  // }
  
  // function Greet(props) {
  //  return (
  //    <h1> Hello {props.phrase}. My name is {props.name} </h1>
  //    )
  // }
  
  // function GreetAll(){
  //   return (
  //     <div>
  //       <Greet phrase="world" name="Sam"/>
  //       <Greet phrase="world" name="John"/>
  //       <Greet phrase="world" name="Lenny"/>
  //     </div>
  //   )
  // }
  
  // ReactDOM.render(<GreetAll />, document.getElementById('root'));
  // ReactDOM.render(<Greet />, document.getElementById('root'));
  // ReactDOM.render(<Greet phrase='world!!!' name="Ivan"/>, document.getElementById('root'));
  
  // let element = <Greet phrase='world!!!' name="Ivan"/>;
  // ReactDOM.render(element, document.getElementById('root'));
  // ReactDOM.render(<App />, document.getElementById('root'));
  
  // If you want your app to work offline and load faster, you can change
  // unregister() to register() below. Note this comes with some pitfalls.
  // Learn more about service workers: http://bit.ly/CRA-PWA
  serviceWorker.unregister();
  