#12773: Data.Functor.Classes instances for ZipList -------------------------------------+------------------------------------- Reporter: Iceland_jack | Owner: Type: feature request | Status: new Priority: low | Milestone: Component: Core Libraries | 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: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by RyanGlScott): I'll repeat what I stated [https://ghc.haskell.org/trac/ghc/ticket/11135#comment:25 here]: if you really want these instances now, we'd be happy to take a patch that adds them. I avoided any new `Eq1`/`Ord1`/`Read1`/`Show1`/`Eq2`/`Ord2`/`Read2`/`Show2` instances (other than the ones brought over from `transformers`) since I lacked a mechanism to derive all of these classes, which would have made implementing a lot of these instances tiresome. See also #12457, which aims to find a way to integrate `deriving` into the larger metaprogramming picture. If we had this, we wouldn't have to bake the deriving algorithms for eight more typeclasses into GHC, which would make adding all of these instances far less painful. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12773#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler