#10281: Type error with Rank-n-types -------------------------------------+------------------------------------- Reporter: rhjl | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (Type | Version: 7.10.1 checker) | Keywords: Resolution: | Architecture: Operating System: Unknown/Multiple | Unknown/Multiple Type of failure: GHC rejects | Test Case: valid program | Peirce_eq_LEM.hs Blocked By: | Blocking: Related Tickets: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by simonpj): When I copy/paste this into my emacs buffer the foralls show up ok but the a's and b's (and much else besides) do not. Could you do it in ASCII please? Do you think the program needs impredicative polymorphism? If so, GHC just doesn't properly support that, notwithstanding the partially implemented `-XImpredicativeTypes`. I'm not sure what "it accepts it if the product type is replaced by tuples" means. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10281#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler