promises.js

  async function main(url) {
    const root = document.getElementById('root');
    root.innerHTML = 'Hello world';
    setTimeout(() => {
      root.innerHTML = 'Something else';
    }, 2000);

    root.addEventListener('click', () => {
      root.innerHTML = 'You clicked root!';
      root.innerHTML = 'Hej Class!';
    });

    try {
      const evt = await addEventPromise(root);
      root.innerHTML = 'hello after await';
    } catch {
      root.innerHTML = 'Error from catch';
    }

    const promise = addEventPromise(root);

    promise.then(evt => {
      root.innerHTML = 'Hello from promise';
    });
    promise.then(evt => {
      console.log('Hello from other promise then');
    });
    promise.catch(error => {
      root.innerHTML = error.message;
    });
  }