I am willing to help on this as much as I can. Unfortunately I don't think you want me to lead the discussion or make decisions on this - many of these discussions seem over my head. I will continue to study them though and see if the sink in more.
I do think almost all of these proposals want a dot selector, so it is a good idea for Haskell to require the normal function (composition) dot to have spaces around it - should this be brought to the Haskell Prime committee? Greg Weber On Fri, Dec 23, 2011 at 1:52 PM, Simon Peyton-Jones <[email protected]>wrote: > Are Records stalled out again? I am perfectly willing to leave the fate > of records up to a willing and capable implementer. That seems much better > than waiting another 5 years for perfection :)**** > > ** ** > > Yes, they are stalled again. The “simple solution” turned out to be not > simple. I wrote it up at length in **** > > > http://hackage.haskell.org/trac/ghc/wiki/Records/OverloadedRecordFields*** > * > > There are various unsatisfactory aspects of the proposal, particularly > concerning record update. I am not sure how to resolve them. **** > > ** ** > > There was essentially no reaction. As it’s quite a lot of work to > implement, and no one seemed to care very much, I put it back on the back > burner. So that’s where it stands.**** > > ** ** > > Meanwhile, AntC has put forth another proposal that I have not had time to > look at in detail.**** > > > http://www.haskell.org/pipermail/glasgow-haskell-users/2011-December/021298.html > **** > > ** ** > > *What this needs is someone (not me) to lead the discussion and try to > make sure it makes progress*. For example, does AntC’s proposal work? Is > it better than the one I articulated? Are any other variants worth > considering? Is the gain from overloading record fields worth the pain or > design and implementation? Volunteers, stand forth!**** > > ** ** > > Simon**** > > ** ** > > ** ** > > *From:* Greg Weber [mailto:[email protected]] > *Sent:* 09 December 2011 19:38 > *To:* Simon Peyton-Jones > *Cc:* Wolfgang Jeltsch; [email protected] > > *Subject:* Re: Records in Haskell**** > > ** ** > > Are Records stalled out again? I am perfectly willing to leave the fate of > records up to a willing and capable implementer. That seems much better > than waiting another 5 years for perfection :)**** > > ** ** > > As an intermediate step, is it possible to put a warning in 7.4 when the > dot operator is used without a space so that it can be reserved for usage > with a records solution? Or will the new records solution be turned on by > an extension anyways?**** > > ** ** > > On Mon, Nov 7, 2011 at 10:21 AM, Simon Peyton-Jones <[email protected]> > wrote:**** > > | would inclusion of such a record system into GHC mean that plans for > | first-class labels (<http://tinyurl.com/7fppj32>) are abandoned? That > | would be a pity, since first-class labels are very useful to implement > | record systems that go beyond what the abovementioned record system > | provides. See, for example, my work on records: > | < > http://www.informatik.tu-cottbus.de/~jeltsch/research/ppdp-2010-paper.pdf> > | <http://hackage.haskell.org/package/records>**** > > The story is summarised at > http://hackage.haskell.org/trac/ghc/wiki/Records > > First-class labels are one point in the vast swamp of competing and > overlapping proposals for records. I think they are summarise here: > http://hackage.haskell.org/trac/ghc/wiki/ExtensibleRecords > I am unsure which of this list of proposals you are referring to. The URL > you quote is this > http://hackage.haskell.org/trac/haskell-prime/wiki/FirstClassLabels > but it doesn't seem to actually contain a design, merely some options for > a design that is implicit. If you do have a design you advocate, it would > be good to add it to the list at > http://hackage.haskell.org/trac/ghc/wiki/ExtensibleRecords > perhaps explaining which of the other members of the list it subsumes. > > Because there are so many proposals I have not gone ahead with any of > them. The most recent thread, articulated at > http://hackage.haskell.org/trac/ghc/wiki/Records > is to ask what is the *smallest change* that would solve the *most > pressing problem*, namely the inability to use the same field name in > different records. First class labels is (I assume) much more ambitious. > But maybe not. > > Anything you can do to bring clarity to the swamp, by editing the above > two pages, would be a great service to the community. At the moment, we > are stuck in an infinite loop. > > Simon**** > > > _______________________________________________ > Glasgow-haskell-users mailing list > [email protected] > http://www.haskell.org/mailman/listinfo/glasgow-haskell-users**** > > ** ** >
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