TypeScript: Nominal Typing using symbols

nominalTyping.ts

declare const Nominal: unique symbol;

type NominalType<TType, TNominal extends string> = TType & {
  [Nominal]: TNominal;
};

type UserId = NominalType<string, 'user_id'>;

type BookId = NominalType<string, 'book_id'>;

function doSomething(userId: UserId, bookId: BookId) {
  console.log('OK');
}

// this is OK
doSomething('123' as UserId, '456' as BookId);

// this is not OK
// doSomething('123', '456');