Yeah, both options suggested are valid, of course. But I really don't want to have a constructor and I'm using Edison where Coll is defined something like:
class Coll c e where empty :: c e insert :: c e -> e -> c e etc., which precludes the fun dep solution. - Hal -- Hal Daume III "Computer science is no more about computers | [EMAIL PROTECTED] than astronomy is about telescopes." -Dijkstra | www.isi.edu/~hdaume On Tue, 23 Apr 2002, Jorge Adriano wrote: > > > class Collection e ce | ce -> e where > > empty :: ce > > insert :: e -> ce -> ce > > member :: e -> ce -> Bool > > > > instance Eq a => Collection a (a -> Bool) where > > empty = (\x -> False) > > insert e f = (\x -> if x == e then True else f x) > > member e f = f e > > This is way better than my solution... > > I had never used multi-parameter classes before, so I forgot the functional > dependency (right name? the "|ce->e"), and there was obviously no need for my > extra constructor. > > J.A. > _______________________________________________ Haskell mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell
