Btw. I already defined my own Apply type (I called it Wrap) because I found it useful. Would you mind to export it from 'transformers'?
You're talking about this transformers issue [1], correct? If so, I doubt that's ever going to happen. The changes to Eq1/Ord1/Read1/Show1 rendered Apply obsolete, since it's no longer necessary to use Apply to define Eq1 instances for nested applications of a type parameter of kind * -> *. Not only that, but there are a couple of datatypes in transformers that already resolve their Eq instances in an identical way to how Apply would (for instance, IdentityT, which is isomorphic to Apply [2]). Ryan S. ----- [1] http://hub.darcs.net/ross/transformers/issue/8 [2] http://hackage.haskell.org/package/transformers-0.5.0.0/docs/src/Control-Mon...