#14845: TypeInType, index GADT by constraint witness -------------------------------------+------------------------------------- Reporter: Iceland_jack | Owner: (none) Type: feature request | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.5 Resolution: | Keywords: TypeInType Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #13895 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): OK so there are two things * A data constructor should not be promoted if it has a constrained type. This should not be hard to arrange. * As comment:12 shows, a kind signature should hove no constraints in it. Surely `checkValidType` is the place for that check. By the time we get to `tcInstBinder` the crime is well past! -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14845#comment:14 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler