JavaScript: async `waitFor` function

waitFor.js

/**
 * Wait for the specified milliseconds.
 */
async function waitFor(msec) {
  await new Promise((resolve) => setTimeout(resolve, msec));
}

Different declaration with the similar behavior:

const waitFor = (msec) => new Promise((resolve) => setTimeout(resolve, msec));

Usage:

// Wait 1000 milliseconds.
await waitFor(1000);

// Wait 3000 milliseconds and print out.
waitFor(3000).then(() => console.log("3 seconds."));