| /** |
| Convert an object with `readonly` properties into a mutable object. Inverse of `Readonly<T>`. |
| |
| This can be used to [store and mutate options within a class](https://github.com/sindresorhus/pageres/blob/4a5d05fca19a5fbd2f53842cbf3eb7b1b63bddd2/source/index.ts#L72), [edit `readonly` objects within tests](https://stackoverflow.com/questions/50703834), and [construct a `readonly` object within a function](https://github.com/Microsoft/TypeScript/issues/24509). |
| |
| @example |
| ``` |
| import {Mutable} from 'type-fest'; |
| |
| type Foo = { |
| readonly a: number; |
| readonly b: string; |
| }; |
| |
| const mutableFoo: Mutable<Foo> = {a: 1, b: '2'}; |
| mutableFoo.a = 3; |
| ``` |
| */ |
| export type Mutable<ObjectType> = { |
| // For each `Key` in the keys of `ObjectType`, make a mapped type by removing the `readonly` modifier from the property. |
| -readonly [KeyType in keyof ObjectType]: ObjectType[KeyType]; |
| }; |