class Counter extends React.Component {
          constructor(props) {
           super(props);
          this.state = { counter: 0 };
     }

      handleClick = () => {
       this.setState(({ counter }) => ({
     counter: counter + 1
      }));
     };

  simError = () => {
     x / 2;
   };

 render() {
   if (this.state.counter === 5) {
     // Simulate a JS error x is not defined
     // this will crash the component `this.simErro()`
     //this.simError()
     // but this will not `setTimeout(this.simError, 0);`
     //setTimeout(this.simError, 0);
  }
     return <h1 onClick={this.handleClick}>{this.state.counter}</h1>;
    }
  }