4 ms·If you need just one, make just one. Why should the class enforce it?by nedbat 4y agoIf you need just one, make just one. Why should the class enforce it?thfuran 4y agoWhy deliberately avoid enforcing design constraints? I mean, why not just make everything a void * and cast as needed and promise not to mess up?nedbat 4y agoYou can enforce the constraint, but it shouldn't be in the class itself. How to you make instances for tests?