#14190: Typeable imposes seemingly redundant constraints on polykinded instances -------------------------------------+------------------------------------- Reporter: dfeuer | Owner: (none) Type: bug | Status: patch Priority: normal | Milestone: 8.4.1 Component: Compiler (Type | Version: 8.2.1 checker) | Resolution: | Keywords: Typeable Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D4000 Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj):
Without it, we have no way to get the kinds of the pieces once we decompose
I think it would be useful to give a concrete example of this, and put that example in a Note with the code for `typeRepKind`. So far I have always supposed that it's a convenience mechanism: you can always pass a `TypeRep` for the kind separately. But maybe I'm wrong. I'm not against `typeRepKind`, just wanting a slam-dunk argument that we need it. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14190#comment:12 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler