What is a mapped type? type Flags = { [K in keyof T]: boolean };

A type that creates new properties by iterating over another type's keys

A type for the Map object from the JavaScript standard library

A type that maps object values at runtime

TypeScript · Middle · Question 5 of 75

What is a mapped type?

type Flags<T> = { [K in keyof T]: boolean };

✓Correct answer: A type that creates new properties by iterating over another type's keys
2A type for the Map object from the JavaScript standard library
3A type that maps object values at runtime

Explanation

[K in keyof T] iterates over the keys. You can change the value type, add or remove modifiers (readonly, ?, -?) and rename keys with as. Partial, Readonly and Record are built on mapped types.

What is a mapped type?

Explanation

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