>>>>> Simon Urbanek writes: > Given that the args of tools:::%notin% don’t match %in% I'd say it was > just a local use more than any deep thought about general use.
Actually, I simply never liked 'table' in %in% or match itself, so I took 'y' instead :-) > Personally, I really like the idea of %notin% because it is very often > that you start typing foo[foo %in% and then realise you want to invert > it and the preceding negation is then cognitively sort of in the wrong > place (reads like "not foo"). I also like %notin% better than %!in% > because I think a salad of special characters makes things harder to > read, but that may be just subjective. Same from here. So add `%notin%` <- function (x, table) is.na(match(x, table)) to base? Best -k > And to your 'why bother' question - I do think it’s better to > standardise common operators in core rather than have packages > re-define it each time. And certainly just importing something that > trivial from another package is a bad idea given the dependency > implications. (On the flip side: if you start using it you need to > depend on recent R which may not be feasible in some environments, but > then if that was always the argument we’d never add anything new :P). > Cheers, > Simon >> On 28 Nov 2025, at 08:24, Duncan Murdoch <[email protected]> wrote: >> >> On 2025-11-27 11:58 a.m., Marcelo Ventura Freire wrote: >>> If it is not a rhetorical question about a closed issue (if it is, tell me >>> and I will shut up), this inclusion [1] would be useful (since it was >>> exported and rewritten so many times by so many people and will keep >>> being), [2] would create an uniformization (since it was and will be >>> written under so many names before), [3] would not break stuff (since it is >>> not altering the interface of any already existing function nor it is >>> overwriting any symbol with a diverse use), [4] would not be neither a >>> complex nor a tiringsome inclusion (even I myself could do it in a single >>> 1-line pull request, hypothetically speaking) and [5] would benefit users >>> all around. >>> I am not naive to the point of believing that an alteration to the R core >>> would have few repercussions and surely there must be reasons why it was >>> not done before. >> >> I don't know why it was added to tools but not exported, but here is my >> guess: >> >> - A member of R Core agrees with you that this operator is useful. This >> appears to have happened in 2016 based on the svn log. >> - It already existed in some contributed package, but base packages can't >> import anything from non-base packages, so it needed to be added. >> - It wasn't exported, because that would break some packages: >> - the ones that export something with that name would now receive a check >> message about the conflict. >> - if those packages stopped exporting it, then any package that imported >> from one of them would have to stop doing that, and import it from the base >> package instead. >> - It is very easy to write your own, or to import one of the existing ones, >> so a lot of work would have been generated for not very much benefit. >> >> R Core members try to be careful not to generate work for others unless >> there's enough of a net benefit to the community. They are very busy, and >> many authors of contributed packages who might be affected by this change >> are busy too. >> >> >>> But, in the end, this inclusion would be just a seemingly unharmful syntax >>> sugar that could be shared, like it was with "\" for the reserved word >>> "function", but with waaaay less work to implement. >> >> The difference there is that it added new syntax, so as far as I know, it >> didn't affect any existing package. Personally I don't see that it really >> offered much of a benefit (keystrokes are cheap), but lots of people are >> using it, so I guess some others would disagree.> >>> If it is not a dumb proposal, I can just include it in the wishlist of >>> features in Bugzilla as prescribed in the contributor's page or I can do >>> that PR myself (if you propose more work to others, the sensible thing to >>> do is at least to offer yourself to do it, right?). In either case, I >>> create more work to the dev team, perhaps to different people. >> >> It's hard for you to do the coordination work with all the existing packages >> that use a similar operator, so I don't think that's really feasible. >> >>> Thanks for taking your time to answer me. >> >> No problem. I'm sitting in an airport waiting for a plane, so any >> distraction is a net benefit for me! >> >> Duncan Murdoch> >>> Marcelo Ventura Freire >>> Escola de Artes, Ciências e Humanidades >>> Universidade de São Paulo >>> Av. Arlindo Bettio, 1000, >>> Sala Paulo Freire (Sala Coletiva 252), Prédio I1 >>> Ermelino Matarazzo, São Paulo, SP, Brasil >>> CEP 03828-000 >>> Tel.: (11) 3091-8894 >>> Em qui., 27 de nov. de 2025 às 14:15, Duncan Murdoch >>> <[email protected] <mailto:[email protected]>> escreveu: >>> The R sources already contain an operator like that, though it is not >>> exported. tools:::`%notin%` is defined as >>> function (x, y) >>> is.na <http://is.na>(match(x, y)) >>> Several CRAN packages export a similar function, e.g. omnibus, mefa4, >>> data.table, hutils, etc. So I think if it was exported by R that's a >>> better name, but since it is easy to write yourself or import from some >>> other package, why bother? >>> Duncan Murdoch >>> On 2025-11-27 9:19 a.m., Marcelo Ventura Freire via R-devel wrote: >>> > Hello, dear R core developers >>> > >>> > >>> > I have a feature suggestion and, following the orientations in >>> > https://contributor.r-project.org/rdevguide/chapters/ >>> submitting_feature_requests.html <https://contributor.r-project.org/ >>> rdevguide/chapters/submitting_feature_requests.html>, >>> > I have searched in Bugzilla to the best of my capabilities for >>> suggestions >>> > like the one I have in mind but found no results (however, I can >>> be wrong). >>> > >>> > My idea is including this line >>> > >>> > `%!in%` <- function(x, table) match(x, table, nomatch = 0L) == 0L >>> > >>> > between lines 39 and 40 of the file "src/library/base/R/match.R". >>> > >>> > My objective is to create a "not in" operator that would allow us >>> to write >>> > code like >>> >> value %!in% valuelist >>> > instead of >>> >> ! value %in% valuelist >>> > which is in line with writing >>> >> value1 != value2 >>> > instead of >>> >> ! value1 == value2 >>> > >>> > I was not able to devise any reasonable way that such inclusion >>> would break >>> > any already existing heritage code unless that operator would be >>> defined >>> > otherwisely and it would improve (however marginally) the >>> readability of >>> > future code by its intuitive interpretation and by stitching >>> together two >>> > operators that currently stand apart each other. >>> > >>> > So, if this suggestion was not already proposed and if it is seen as >>> > useful, I would like to include it in the wishlist in Bugzilla. >>> > >>> > I would appreciate any feedback, be it critic or support, and I >>> hope I have >>> > not crossed any communicational rule from the group. >>> > >>> > Many thanks! 😄 >>> > >>> > >>> > >>> > Marcelo Ventura Freire >>> > Escola de Artes, Ciências e Humanidades >>> > Universidade de São Paulo >>> > Av. Arlindo Bettio, 1000, >>> > Sala Paulo Freire (Sala Coletiva 252), Prédio I1 >>> > Ermelino Matarazzo, São Paulo, SP, Brasil >>> > CEP 03828-000 >>> > Tel.: (11) 3091-8894 >>> > >>> > [[alternative HTML version deleted]] >>> > >>> > ______________________________________________ >>> > [email protected] <mailto:[email protected]> mailing list >>> > https://stat.ethz.ch/mailman/listinfo/r-devel <https:// >>> stat.ethz.ch/mailman/listinfo/r-devel> >>> >> >> ______________________________________________ >> [email protected] mailing list >> https://stat.ethz.ch/mailman/listinfo/r-devel >> > ______________________________________________ > [email protected] mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
