On Tue, Feb 7, 2012 at 7:23 AM, Mikhail Vorozhtsov <mikhail.vorozht...@gmail.com> wrote: > Even better, you can write > > type ExistentialWith c e = (Existential e, c ~ ConstraintOf e) > > instead of > > class (Existential e, c ~ ConstraintOf e) => ExistentialWith c e > instance (Existential e, c ~ ConstraintOf e) => ExistentialWith c e > > and drop UndecidableInstances.
I actually mentioned this in the preceding point of the [snip]. The problem is that it's not even better because you can't partially apply it. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
