Positive

[BLS]

I would prefer a more general, ADA like, solution.

// ADA
SUBTYPE Natural IS Integer RANGE 0 .. Integer'Last;
SUBTYPE NonNegFloat IS Float RANGE 0.0 .. Float'Last;
and also :
SUBTYPE CapitalLetter IS Character RANGE 'A' .. 'Z';


just my 2 euro cents;
Bjoern