10_tofu.hs

class Tofu t where  
    tofu :: j a -> t a j  

data Frank a b  = Frank {frankField :: b a} deriving (Show)  

instance Tofu Frank where  
    tofu x = Frank x  

data Barry t k p = Barry { yabba :: p, dabba :: t k }  

instance Functor (Barry a b) where  
    fmap f (Barry {yabba = x, dabba = y}) = Barry {yabba = f x, dabba = y}