I think Alex wanted the conditional execution of the quot. if the key doesn't exist in the assoc, change-at provides f as value, but still stores the newvalue in the assoc at the given key.
Jon On Mon, Aug 17, 2020 at 6:18 PM John Benediktsson <mrj...@gmail.com> wrote: > > https://docs.factorcode.org/content/word-change-at,assocs.html > > On Aug 17, 2020, at 8:31 AM, Alexander Ilin <ajs...@yandex.ru> wrote: > > Hello! > > I came up with this code, because I could not quickly find an existing word > for this. > Did I miss it? If not, would it be a useful addition to the assocs vocab? > > ! If key exists in the assoc, change its value with quot. > : ?change-value ( assoc key quot: ( value -- value' ) -- assoc' ) > [ swap pick set-at ] compose [ 2dup of ] dip [ drop ] if* ; inline > > ! Usage example: > : ?decode-opt ( assoc -- assoc' ) > "opt" [ string>options ] ?change-value ; > > > ---=====--- > Александр > > > > _______________________________________________ > Factor-talk mailing list > Factor-talk@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/factor-talk > > _______________________________________________ > Factor-talk mailing list > Factor-talk@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/factor-talk _______________________________________________ Factor-talk mailing list Factor-talk@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/factor-talk
