Something I wanted to try to implement before GHC 7.12 are extensions to DeriveFunctor, DeriveFoldable, and DeriveTraversable which would allow for automatic derivation of Bifunctor, Bifoldable, and Bitraversable. (This has already been implemented using Template Haskell in an unreleased version of the bifunctors package [1], so implementing it in GHC should be straightforward.)
I haven't made an issue for this yet since I was waiting on the results of #10448 [2] (which would put Bifoldable and Bitraversable in base, in addition to Bifunctor, which was added in 7.10). Currently, Edward Kmett is listed as the owner of that issue, but I would be happy to tackle it if it means we could get it in time for GHC 7.12. Ryan S. ----- [1] https://github.com/ekmett/bifunctors/tree/8e975aead363802610dedccf414b884f9b39b1f4 [2] https://ghc.haskell.org/trac/ghc/ticket/10448 _______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs
