TypeScript

Promise.race returning a union of types in TypeScript

TypeScriptAsync & PromisesPromise Combinators Typingintermediate

What this snippet does

Unlike Promise.all, Promise.race resolves with the value of the first settled promise, so the type is a union of all inputs.

Expected output

1

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.

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