On Wed, 6 Feb 2008, Denis Bueno wrote: > On Feb 6, 2008 9:00 AM, Henning Thielemann > <[EMAIL PROTECTED]> wrote: > > On Wed, 6 Feb 2008, Matthew Pocock wrote: > > > class Buildable b where > > > empty :: b a --makes an empty b with elements of type a > > > insert :: a -> b a -> b a --inserts the new element into the buildable > > > > How can this interface be used both for lists and maps? [...] > > One solution is to change the class slightly: > > class Buildable t x where > empty :: t > insert :: x -> t -> t > > instance Buildable (Map k a) (k, a) where > empty = Map.empty > insert = uncurry Map.insert
ok, maybe with functional dependency t -> x _______________________________________________ Haskell-Cafe mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell-cafe
