I think a general "no TH changes after the first RC" seems reasonable as part of the broader feature freeze.
But this case seems decidedly more of a bug fix than a feature addition, since TH *should* have feature parity with Haskell syntax. So I'd favor merging Iavor's patch. I also like Austin's suggestion that we require template-haskell patches alongside new syntax. Eric On Thu, Apr 14, 2016, at 13:59, Richard Eisenberg wrote: > I'm happy to be overruled on this, but I vote against this change for GHC > 8. Personally, I like to have a policy of "no TH changes after the first > RC". This gives ample time for TH clients to update their code. Iavor's > suggestion would likely involve a new part of the InstanceD constructor, > which would affect anyone constructing or matching on this constructor. > If the change involved, say, only adding new functionality without > changing anything existing, I would be more willing to include for GHC 8. > > And, yes, I agree with Austin. > > Richard > > On Apr 14, 2016, at 2:17 PM, Austin Seipp <[email protected]> wrote: > > > Here's a question, on top of this one: why don't we require > > template-haskell changes for most corresponding syntax changes? We > > tend to play catch up with template-haskell sometimes and it's > > relatively strange. I mean, in some sense, we could have said a while > > back "This needs another revision, please add template haskell > > support" and avoided it all. > > > > Richard has a better insight into this than I do, I'm sure, but it > > seems - to me, anyway - like template-haskell support is a reasonable > > bar for most surface-level syntax change to cross, before getting > > merged. > > > > My intuition tells me that, most of the time, a lot of us simply > > forget to make the changes, or ask for them in reviews, and so it > > goes. > > > > On Thu, Apr 14, 2016 at 1:12 PM, Ben Gamari <[email protected]> wrote: > >> Iavor Diatchki <[email protected]> writes: > >> > >>> Hello, > >>> > >>> Now that "OVERLAPPING" and "OVERLAPPABLE" are pragmas on the instances, do > >>> we have a way to generate instances with such pragmas using Template > >>> Haskell? I can't seem to find a way to do this, which is unfortunate. > >>> > >>> If I am not missing anything, would there be objections to adding it to > >>> the > >>> TH library before the next release---I would volunteer to do the change > >>> ASAP. > >>> > >> Indeed this is an unfortunate gap. Given that this shouldn't be a > >> terribly invasive change I would be alright with this if Richard approves. > >> > >> Cheers, > >> > >> - Ben > >> > >> > >> _______________________________________________ > >> Libraries mailing list > >> [email protected] > >> http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries > >> > > > > > > > > -- > > Regards, > > > > Austin Seipp, Haskell Consultant > > Well-Typed LLP, http://www.well-typed.com/ > > _______________________________________________ > ghc-devs mailing list > [email protected] > http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs _______________________________________________ ghc-devs mailing list [email protected] http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs
