#12131: Can't solve constraints with UndecidableSuperClasses but can infer kind (+ undesired order of kinds) -------------------------------------+------------------------------------- Reporter: Iceland_jack | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Resolution: | Keywords: | UndecidableSuperClasses Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #11480 #12025 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by Iceland_jack): `Product` doesn't make ghc spin, but oddly `j` appears before `i` even though `Cat i` appears before `Cat j`, etc. {{{ ghci> :t Product Product :: forall j i (p :: i -> i -> *) (q :: j -> j -> *) (a :: (i, j)) (b :: (i, j)). p (Fst a) (Fst b) -> q (Snd a) (Snd b) -> Product p q a b }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12131#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler