/**
 * Make all properties and nested properties of an object readonly. This type
 * is similar to `Readonly<T>` but it also makes nested properties readonly.
 *
 * @template T The type to make readonly.
 * @example ReadonlyDeep<{ a: { b: string } }> = { readonly a: { readonly b: string } }
 */
type Immutable<T> = {
    readonly [P in keyof T]: T[P] extends Record<PropertyKey, unknown> ? Immutable<T[P]> : T[P] extends any[] ? Immutable<T[P]> : T[P];
};

export type { Immutable };