On 02/07/2012 04:05 PM, Gábor Lehel wrote:
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.
Ah, sorry, I got sloppy. Have you encountered situations where partial
application of such "constraint aliases" becomes a problem?
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