JavaScript · Senior · Question 50 of 75

Why shouldn't you pass an `async` function as the executor in `new Promise(async (resolve) => ...)`?

✓Correct answer: An error after await won't reject the promise - it hangs
2The Promise constructor throws TypeError for any async function
3It works, but the executor and the promise run twice

Explanation

The constructor ignores the promise returned by an async executor, so an exception after await becomes an unhandled rejection, and the outer promise stays pending. If there's already an await inside, the new Promise wrapper usually isn't needed at all - an async function is enough.

Why shouldn't you pass an `async` function as the executor in `new Promise(async (resolve) => ...)`?

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Why shouldn't you pass an async function as the executor in new Promise(async (resolve) => ...)?

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Why shouldn't you pass an `async` function as the executor in `new Promise(async (resolve) => ...)`?