#11207: GHC cannot infer injectivity on type family operating on GHC.TypeLits' Nat, but can for equivalent type family operating on user-defined Nat kind -------------------------------------+------------------------------------- Reporter: duairc | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.11 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 jstolarek): Replying to [comment:6 goldfire]:
I do think that generalized injectivity is the fastest way toward what you want, though. Note however, that generalized injectivity will not make it into 8.0 (unless miracle happens), which means over a year of waiting until it makes it into next stable release.
-- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11207#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler