S.D.Mechveliani (mechvel@math.botik.ru) wrote: [snip] : The basic algebra library BAL : http://www.botik.ru/pub/local/Mechveliani/basAlgPropos/bal-pre-0.01/ : : suggests class Cast a b where cast :: a -> b -> a I just want to add that this is almost similar to a mechanism I've implemented. You really need this. Regards, Marc van Dongen