/**
 * Make a type and all its (sub) properties optional.
 */
export type DeepPartial<T> =
    T extends any[] ? DeepPartialArray<T[number]> :
    T extends object ? DeepPartialObject<T> :
    T;
interface DeepPartialArray<T> extends Array<DeepPartial<T>> {}
type DeepPartialObject<T> = {
    [P in keyof T]+?: DeepPartial<T[P]>;
};