Type Signature · #30 · 2026-05-04
What is type `R`?
TypeScript ·Difficulty 2/3
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 GetExt<T> = T extends `${string}.${infer E}` ? E : never;
type R = GetExt<'app.tsx'>;
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Press 1 through 4, or tap a numbered choice, to answer. Back to hub