On Tue, Nov 29, 2011 at 10:29 AM, Joachim Breitner <m...@joachim-breitner.de> wrote: > Hi, > > Am Dienstag, den 29.11.2011, 07:43 +0200 schrieb Michael Snoyman: >> Since the release of deepseq 1.2, we've had a bit of a problem: when >> using the newest versions of packages on Hackage, there is no NFData >> instance available for the containers types. When GHC 7.4 comes out >> with its newer version of containers, this will be addressed, but >> we'll still have problems for users of older GHC releases. >> >> I'd like to suggest a solution: a new package called >> containers-deepseq. Using conditional compilation, it will provide an >> orphans NFData instance for all containers types when deepseq >= 1.2 >> and containers < 0.5. Packages (e.g., aeson) would then depend on >> containers-deepseq and simply import the module whenever they rely on >> the NFData instances. When GHC 7.4 comes out, the package will >> essentially be a no-op. >> >> Does this make sense? > > from a distro point of view: Please void this if possible; every > additional package causes us work. (Although we’d likely just not > upgrade containers before 7.4.1 and patch out the dependency in the > cabal file when we switch to 7.4.1.) > > Why can’t you put the instances in containers, guarded by some #ifs? I > don’t see the point of a separate package for these 15 lines of code.
Because containers cannot be updated: you're stuck with whatever version comes with GHC. Michael _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe