On Wed, Nov 18, 2009 at 4:12 PM, Edward Kmett <ekm...@gmail.com> wrote: > > Qualified imports are some times problematic when you need to work with > classes from the module. You can't define a member of two instances from > different two modules that define classes with conflicting member names. > This can lead to situations where you have no option but to have orphan > instances. > > module Bar where > class Foo a where > foo :: a > > module Baz where > class Quux a where > foo :: a > > module Quaffle where > import qualified Bar > import qualified Baz > > instance Bar.Foo Int where > Bar.foo = 1 > -- ^- syntax error. > > instance Baz.Quux Int where > Baz.foo = 2 > > I suppose this could possibly be fixed if something deep in the parser > allowed a QName there.
Try Quaffle without the qualifications. > module Quaffle where > import qualified Bar > import qualified Baz > > instance Bar.Foo Int where > foo = 1 > > instance Baz.Quux Int where > foo = 2 -- Dave Menendez <d...@zednenem.com> <http://www.eyrie.org/~zednenem/> _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
