I agree with Richard. We're still working up the right way to get this functionality to work, and sadly the simple solution doesn't cover enough cases. As I noted during the day, this approach doesn't scale. Let's revert.
-Edward > On Sep 25, 2013, at 8:38 PM, Richard Eisenberg <e...@cis.upenn.edu> wrote: > > In light of the conversations I've been having with Edward and others, I, > too, wonder if we should wait a little before doing this. There is no burning > fire here. Though we have Coercible in 7.8, that doesn't mean we *have* to > use it. The old trick to use unsafeCoerce in the situations Edward wants to > improve will still work, and it will remain as safe as it was before (i.e., > not at all). > > In the end, I agree with Joachim that Coercible should try to have a low > profile in 7.8. I do think that the ideas behind fmapCoerce -- that is, > making sure that the new `coerce` primitive is used to the best effect -- > are great. But I am not convinced that we've found the best possible way to > do it. > > Richard > >> On Sep 25, 2013, at 6:22 PM, Ross Paterson wrote: >> >>> On Wed, Sep 25, 2013 at 10:18:51PM +0200, Joachim Breitner wrote: >>> given the recently intensified urge to make GHC a more community driven >>> project, may I suggest to reduce the amount of off-list discussions? I >>> find it very confusing if some discussions happen on list, some >>> discussion on list with certain people explictily CC’ed, and some >>> discusisons off-list, and some alternating between these. I believe we >>> are all able to ignore discussions on the list that are not relevant for >>> us, but on-list discussions are easily referenced and re-read later. >> >> I agree with all that, and also share Johan's alarm at the sudden >> appearance of coerce in this class. >> >> On the substance, I don't think Functor is the right place for this, >> as it's about lifting isomorphisms rather than functions, and type >> constructors don't have to be functors to support that. >> _______________________________________________ >> ghc-devs mailing list >> ghc-devs@haskell.org >> http://www.haskell.org/mailman/listinfo/ghc-devs > > _______________________________________________ > ghc-devs mailing list > ghc-devs@haskell.org > http://www.haskell.org/mailman/listinfo/ghc-devs _______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://www.haskell.org/mailman/listinfo/ghc-devs
