#13333: Typeable regression in GHC HEAD -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: bgamari Type: bug | Status: new Priority: high | Milestone: 8.2.1 Component: Compiler (Type | Version: 8.1 checker) | Resolution: | Keywords: typeable Operating System: Unknown/Multiple | Architecture: Type of failure: GHC rejects | Unknown/Multiple valid program | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): I think that if we have `t :: k1` and `c :: k1 ~ k2` and {{{ Constraints: [W] c :: Typeable k2 (t |> c) }}} then we can simplify the wanted constraint to {{{ Bindings: c = c1 |> Typeable ?? c Constraints: [W] c1 :: Typeable k1 t }}} Richard do you agree? What is the `??`? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13333#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler