What this snippet does
Failing to await an async function assigns the Promise object itself, causing a type mismatch between Promise<number> and number.
Expected output
Compile Error: Type 'Promise<number>' is not assignable to type 'number'.
Why practise typing this
Typing async & promises code builds muscle memory for the symbols and indentation TypeScript uses most, which prose-based typing tests never cover. DevType measures your words per minute and accuracy on this snippet and tracks the individual characters you mistype, so later lessons can target them.
More TypeScript practice
- Defining a function returning a typed PromiseAsync & Promises · intermediate
- Fetching user data with typed async/awaitAsync & Promises · intermediate
- Awaited type behavior in async functionsAsync & Promises · intermediate
- Returning a Promise of a PromiseAsync & Promises · intermediate
- Rejecting a Promise with an untyped errorAsync & Promises · intermediate
- Typing Promise.all with mixed typesAsync & Promises · intermediate