Re: Proposal: Add `restriction` to Data.Map and Data.IntMap

Restricting the domain of a function is common terminology in maths. I like the original name 'restrict' or 'restrictTo' or 'restrictKeys'. Intersection is a symmetric operation, so that name is less suitable, imho. On 14.07.2016 17:41, amindfv@gmail.com wrote:

+1 to the function, +1 to 'restrictKeys' or 'intersectKeys'

Tom

El 14 jul 2016, a las 11:01, Iavor Diatchki mailto:iavor.diatchki@gmail.com> escribió:

...

I've also needed this in the past, so +1.

I think the bike-shed should be colored: intersectKeys or restrictKeys

-Iavor

On Thu, Jul 14, 2016 at 6:39 AM, Edward Kmett mailto:ekmett@gmail.com> wrote:

+1 on the functionality, not a fan of the name.

Bikeshed color: intersectionWithSet?

-Edward

On Thu, Jul 14, 2016 at 9:36 AM, Ivan Lazar Miljenovic mailto:ivan.miljenovic@gmail.com> wrote:

On 14 July 2016 at 22:45, Jake McArthur mailto:jake.mcarthur@gmail.com> wrote: > I like the function, but I'd like to bikeshed a bit. The name "restriction" > seems confusing to me, or at least I don't understand the etymology. As of > now I'd prefer something like "filterMember". filterMember is to (filter . > flip member) as concatMap is to (concat . map). That's not perfectly > consistent due to the flip, but I think it's close enough to motivate the > name.

More possible bikeshed colours:

* intersectionWith/setIntersection to reflect the similarity with the existing intersection functions

* restrictTo (which may fit better with the proposed argument order than the ones above)

If we keep this argument order, then I think a name similar to restriction as originally proposed makes more sense than an intersection one (as the arguments are flipped compared to the other similarly named functions).

> > > On Thu, Jul 14, 2016, 5:39 AM Andreas Abel mailto:abela@chalmers.se> wrote: >> >> +1. >> >> On 14.07.2016 06:45, David Feuer wrote: >> > Cale Gibbard proposes the following: >> > >> > Data.IntMap.restriction :: IntSet -> IntMap a -> IntMap a >> > Data.Map.restriction :: Ord k => Set k -> Map k a -> Map k a >> > >> > In each case, the map is filtered to contain only the keys that are >> > also found in the set. This can be implemented efficiently using a >> > slightly stripped-down version of Data.Map.intersection. >> > >> > David Feuer >> > _______________________________________________ >> > Libraries mailing list >> > Libraries@haskell.org mailto:Libraries@haskell.org >> > http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries >> > >> >> >> -- >> Andreas Abel <>< Du bist der geliebte Mensch. >> >> Department of Computer Science and Engineering >> Chalmers and Gothenburg University, Sweden >> >> andreas.abel@gu.se mailto:andreas.abel@gu.se >> http://www2.tcs.ifi.lmu.de/~abel/ >> _______________________________________________ >> Libraries mailing list >> Libraries@haskell.org mailto:Libraries@haskell.org >> http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries > > > _______________________________________________ > Libraries mailing list > Libraries@haskell.org mailto:Libraries@haskell.org > http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries >

-- Ivan Lazar Miljenovic Ivan.Miljenovic@gmail.com mailto:Ivan.Miljenovic@gmail.com http://IvanMiljenovic.wordpress.com _______________________________________________ Libraries mailing list Libraries@haskell.org mailto:Libraries@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries

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-- Andreas Abel <>< Du bist der geliebte Mensch. Department of Computer Science and Engineering Chalmers and Gothenburg University, Sweden andreas.abel@gu.se http://www2.tcs.ifi.lmu.de/~abel/