Math::Logic This is an object module which provides pure 2 or 3 or multi value logic; it is intended to supercede my Math::Logic3 which only provided pure 3 value logic. It should appear in my CPAN directory ID=SUMMER in a day or so; it is available from my own site now. Is this naming acceptable? (And if not helpful suggestions appreciated:-) Thanks. _______________________________________________ Mark Summerfield http://www.perlpress.com