TypeScript

Defining a function returning a typed Promise in TypeScript

TypeScriptAsync & PromisesTyping Promisesintermediate

What this snippet does

Explicitly typing Promise<T> ensures that the consumer knows exactly what data type the asynchronous operation resolves with.

Expected output

done

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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