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JavaScript React Basics Thinking in Components Composing Components

G H Mahimaanvita
G H Mahimaanvita
16,234 Points

uncaught reference error: App is not defined

please help me

const Header = () => {
 return (
   <header>
   <h1>scoreboard</h1>
   <span className="stats">Players:1</span>
   </header>

 );

}


const Player = () => {
  return (
    <div className="player">
     <span className="player-name">Mahima</span>
    <Counter />
    </div>
  );
}

const Counter = () => {
  return (
    <div className="counter">
    <button className="counter-action decrement">-</button>
    <span className="counter-score">35</span>
    <button className="counter-action increment">+</button>


    </div>


  );


const App = () => {
return (
  <div className = "scoreboard">
  <Header/>
  <Player />
  </div>


);
}



}
ReactDOM.render(
<App />,
  document.getElementById("root")


);

this shows an uncaught reference error saying App wasn't defined. However, when I copied it into babeljs.io, it didn't show any error.
when I tried replacing <App/> with

ReactDOM.render(
  <div className = "scoreboard">
  <Header/>
  <Player />
  </div>,
  document.getElementById("root")


);

it worked
Please help me to make <App/> work

1 Answer

Paolo Scamardella
Paolo Scamardella
24,828 Points

That is because you have App inside your Counter component.

Your Counter's closing parenthesis "}" is after App's component...need to be outside on it own.