XHR get by Promise and async

gistfile1.txt

function bredListRequest(resolve, reject) {
  const r = new XMLHttpRequest();
  r.open('GET', 'https://api.github.com', true);

  r.onerror = (e) => reject(e, 'error');
  r.onload = () => resolve(r.responseText);
  r.send();
}

function fetchGithubIndex() {
  return new Promise(bredListRequest);
}

function runViaPromise() {
  fetchGithubIndex()
    .then(result => console.log(result)) // XHR response here)
    .catch(e => console.error(e))
}

async function runViaAsync() {
  try {
    const resPromise = fetchGithubIndex();
    const resValue = await resPromise;
    console.log(resPromise); // Promise here
    console.log(resValue); // XHR response here
  } catch (e) {
    console.error(e);
  }
}

const runViaArrowAsync = async () => {
  try {
    const resPromise = fetchGithubIndex();
    const resValue = await resPromise;
    console.log(resPromise); // Promise here
    console.log(resValue); // XHR response here
  } catch (e) {
    console.error(e);
  }
}

const write = async (fetchFn = fetchGithubIndex) => document.write(await fetchFn());

// runViaPromise();
// runViaAsync();
// runViaArrowAsync();
write(fetchGithubIndex);
console.log('end of script');