如何在运行fetch之前等待取值？

async function fetchData() {
  const response = await fetch('https://example.com/data');
  const data = await response.json();
  console.log(data);
}

function fetchData() {
  return new Promise((resolve, reject) => {
    fetch('https://example.com/data')
      .then(response => response.json())
      .then(data => resolve(data))
      .catch(error => reject(error));
  });
}

fetchData().then(data => console.log(data));

function fetchData(callback) {
  fetch('https://example.com/data')
    .then(response => response.json())
    .then(data => callback(data))
    .catch(error => console.log(error));
}

fetchData(data => console.log(data));