#14042: Datatypes cannot use a type family in their return kind -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (Type | Version: 8.0.1 checker) | Keywords: TypeInType, Resolution: | TypeFamilies 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 goldfire): This ticket is actually about regular old datatypes, not data families. Let's solve the datatype problem first, I think. The only part I haven't quite figured out is if we need the coercion relating the declared return kind to `Type` somewhere, but I don't see where it would go, other than the types of constructors. What would the constructor workers look like? I'm not sure. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14042#comment:13 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler