react operator ?? in react code example

Example 1: if else render react

render() {
  const isLoggedIn = this.state.isLoggedIn;
  return (
    <div>
      {isLoggedIn ? (
        <LogoutButton onClick={this.handleLogoutClick} />
      ) : (
        <LoginButton onClick={this.handleLoginClick} />
      )}
    </div>
  );
}

Example 2: javascript in jsx

const name = 'Josh Perez';
const element = <h1>Hello, {name}</h1>;
//notice the use of {...} to jump from jsx to javascript.
ReactDOM.render(
  element,
  document.getElementById('root')
);