Beautiful. this is the CC(nv) pattern, that matches the CA pattern.
The elegance that allows that allows for elegance in making "compounder" modifiers. On Thursday, February 16, 2023 at 12:28:24 p.m. EST, David Lambert <b49p23t...@gmail.com> wrote: Of the new modifier trains, I've found ^:^:_ as "while". A simple test code: increment while less than 8. (With some errors one need kill the j session.) >: (^:^:_) (<&8) 2 8 While=: ^:^:_ u. While v. u.^:v.^:_ > Date: Wed, 15 Feb 2023 13:12:37 +0100 > From: Jan-Pieter Jacobs<janpieter.jac...@gmail.com> > To:programm...@jsoftware.com > Subject: Re: [Jprogramming] Atop parsing > Message-ID: > <cans99cyu9dmv0kgq+sh4dtvxiueqvcoz_if5iwzw_cvuhh4...@mail.gmail.com> > Content-Type: text/plain; charset="UTF-8" > > The reason it's hard to find anything else on modifier trains is that they > have been removed from the language a long time ago (with j501 in 2002, > apparently), and only reintroduced recently with j903. > > Before the reintroduction, the only modifier trains were bidents: > - partially applied conjunctions, yielding adverbs; and > - chained adverbs, being applied to their left argument in order. > They were left over because they are simple, intuitive and easy to remember > (guessing here, as I wasn't around in the J scene yet). > These are explained well inhttps://www.jsoftware.com/help/learning/15.htm . > The adverbs each and every defined in the standard library library are > useful examples of the first kind of bidents: > type&.<'each' > adverb > each > &.> > > The rabbit hole of general modifier trains is deep: they are not completely > intuitive (at least to me) and require a thorough understanding of the > parsing and execution in J, especially when chaining more than three. They > are also not indispensable, as you can write explicit conjunctions and > adverbs to do anything such tacit modifiers would do. I have yet to find a > useful, non-trivial purpose for them... Of course, feel free to use them if > you like the challenge, but there are far more important areas to get to > know in J, like rank. Or all the wonderful labs (in the menu, help > studio >> labs). ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
