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Type Signature · #16 · 2026-04-20

What is type `R`?

TypeScript ·Difficulty 3/3

How to play

Read the TypeScript snippet and pick the correct type from four choices. Think about inference, narrowing, and utility types. Press 1–4 or click to answer.

type Awaited<T> = T extends Promise<infer U> ? U : T;
type R = Awaited<Promise<Promise<number>>>;

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Press 1 through 4, or tap a numbered choice, to answer. Back to hub