Do all `async` functions return Promises? Why or why not?

Q: Do all `async` functions return Promises? Why or why not?

Yes, all `async` functions return Promises. The value returned by the `async` function is wrapped in a resolved Promise, and any error thrown inside the function is wrapped in a rejected Promise.

Difficulty: 4/10

async functions, Promise return semantics, error propagation

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Yes, all async functions return Promises.
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The value returned by the async function is wrapped in a resolved Promise,
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and any error thrown inside the function is wrapped in a rejected Promise.

Scenario Questions

0-2 years experience

1Write a tiny async function that fetches data but doesn't use a return statement. When you call it without await, what do you get?
2If an async function throws an exception before any return, what does the caller see when they try to .then or await it?
3What will the console.log show for `console.log(typeof myAsync())` if `myAsync` is declared with the async keyword but returns nothing?

Follow-up Questions

Can you show a simple async function that returns a non‑Promise value and explain what the caller receives?
What happens to thrown errors inside an async function in terms of the returned Promise?
How does the JavaScript engine treat a thenable returned from an async function?