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Type Signature · #36 · 2026-05-10

What is the type of `r`?

TypeScript ·Difficulty 1/3

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.

function wrap<T = string>(value: T) {
  return { value };
}
const r = wrap(42);

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