#9357: Kind-polymorphic type family accepts unlifted type arguments -------------------------------------+------------------------------------- Reporter: kosmikus | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.2 (Type checker) | Keywords: Resolution: | Architecture: Unknown/Multiple Operating System: | Difficulty: Unknown Unknown/Multiple | Blocked By: Type of failure: GHC | Related Tickets: accepts invalid program | Test Case: | Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- Comment (by simonpj): Good point. It's not impossible that we could accept unboxed ''arguments'' to type families, but unbozed ''results'' would definitely be problematic: how many bits does it take to represent `(F Int)`? Is is held in an integer register or a floating point register. For now I've just made it so that we require a boxed monotype as both argument and result. Simon -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9357#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler