TypeScript · Senior · Question 73 of 75

What does `Object.freeze` return in terms of types?

const config = Object.freeze({ mode: 'dark', retries: 3 });

✓Correct answer: Readonly<...> of the object with literal types for primitive properties (shallow, like the runtime behavior)
2any
3A deeply readonly type

Explanation

Nested objects are neither frozen at runtime nor readonly in the type. as const makes all levels readonly at the type level only.

Further reading

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