import type { Except } from "./except.mjs";
import type { HomomorphicPick } from "./internal/index.mjs";
import type { Simplify } from "./simplify.mjs";
/**
Create a type that makes the given keys optional. The remaining keys are kept as is. The sister of the `SetRequired` type.

Use-case: You want to define a single model where the only thing that changes is whether or not some of the keys are optional.

@example
```
import type {SetOptional} from 'type-fest';

type Foo = {
a: number;
b?: string;
c: boolean;
}

type SomeOptional = SetOptional<Foo, 'b' | 'c'>;
// type SomeOptional = {
// 	a: number;
// 	b?: string; // Was already optional and still is.
// 	c?: boolean; // Is now optional.
// }
```

@group type-fest
*/
export type SetOptional<
	BaseType,
	Keys extends keyof BaseType
> = BaseType extends unknown ? Simplify<Except<BaseType, Keys> & Partial<HomomorphicPick<BaseType, Keys>>> : never;