This depends largely on what you are actually trying to accomplish. You could use Attribute::Types to simulate type-checking, but there's a good chance you don't actually need strong typing.

You could also create the behavior you want using overload and creating appropriate modules from which you can instantiate objects. You might also be looking for integer math. Or, if you're doing input validation, type casting, or something similar, you could use Data::Types.

So, what specifically are you aiming to accomplish?