What does the following mapped type do? type Mutable = { -readonly [K in keyof T]: T[K] }

Question

TypeScript Associate — Hard

What does the following mapped type do? type Mutable = { -readonly [K in keyof T]: T[K] }

Accepted Answer

The mapped type Mutable removes the readonly modifier from all properties of type T. By using the -readonly modifier, it negates the readonly constraint applied to each property in T.