#13327: Figure out how to make sense of Data instances for poly-kinded datatypes -------------------------------------+------------------------------------- Reporter: RyanGlScott | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: libraries/base | Version: 8.0.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #4028 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by RyanGlScott): Edward Kmett laid out an interesting (albeit not terribly practical) proposal for cleaning up the current story in https://mail.haskell.org/pipermail/ghc-devs/2017-February/013850.html. Sadly, his code doesn't actually typecheck due to what I believe is a corollary of #13337. I came up with an even grosser proposal in https://mail.haskell.org/pipermail/ghc-devs/2017-February/013852.html that //does// typecheck, but with emphasis on the "even grosser" part. There's certainly no way I'd want `Data.Data` to adopt that approach as-is. I need to think more on how I can take the programming patterns in these two proposals and clean them up into something palatable. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13327#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler