#11011: Add type-indexed type representations (`TypeRep a`) -------------------------------------+------------------------------------- Reporter: bjmprice | Owner: Type: feature request | Status: new Priority: normal | Milestone: Component: Compiler | Version: Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by bgamari):
If TyCon is unindexed then the first case should just work without it,
Well, not quite. The trouble here is that kinds are necessarily of type `*`. That is, `mkTrCon` has type, {{{#!hs mkTrCon :: forall (k :: *) (a :: k). TyCon -> TTypeRep k -> TTypeRep a }}} That being said, a runtime check will suffice here. This still leaves the question of whether the given `TyCon` may plausibly have the requested kind, but at least this does away with the `unsafeCoerce`s.
in the second case, isn't it possible to do a runtime check that the kinds of rep_f and rep_x agree?
Indeed, this ought to be possible. Thanks for bringing this up! -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11011#comment:31 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler