I think your solution will take care of the assumed semantics of maximum_age but that's a constraint rather than a class variable.

I don't know if there's a different way in Moose to do that, but How do I create static class variables (class data)? may be what the OP is looking for.

In reply to Re^2: Class variables in Moose? by skirnir
in thread Class variables in Moose? by Anonymous Monk

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