> Well then you don't have to test what happens when someone passes a string, an object, or a boolean. That's useless, I still need to test the value's range w

> Well then you don't have to test what happens when someone passes a string, an object, or a boolean. That's useless, I still need to test the value's range which implicitly checks the type. > You have to maintain documentation and you have to maintain tests and you have to maintain assertions Not if I can generate most of it from the specification data.