Actually, thinking about it, that's just apply acting as a verb. Presumably to produce a verb it's either using the "wicked power' bug or a custom hack to the interpreter.
Personally, I have enough problems with J crashing on me and am hoping to fix such issues, so I stay away from verbs returning non-nouns. Thanks, -- Raul On Mon, Apr 7, 2014 at 7:41 PM, Raul Miller <[email protected]> wrote: > Note that you quoted this text: > > 2 ('+/' apply ,) 3 > 5 > > ;) > > Thanks, > > -- > Raul > > > On Mon, Apr 7, 2014 at 6:22 PM, Pascal Jasmin <[email protected]>wrote: > >> '@u'eval >> @a: >> >> '@u' 1 : ''''' 1 : m' >> @'' >> >> >> You are right about it being fairly easy to shoehorn any dyadic verb into >> a modad for apply, but there is a simplicity to eval when a large boxed >> structure made of several variables is the left hand part. >> >> > PPS. For the record: perhaps apply (128!:2) should not produce adverbs >> or >> conjunctions (or verbs); but, it can. >> >> I won't say I don't believe you, but I don't know how. :) >> >> >> >> >> >> ----- Original Message ----- >> From: Jose Mario Quintana <[email protected]> >> To: Programming forum <[email protected]> >> Cc: >> Sent: Monday, April 7, 2014 4:32:47 PM >> Subject: Re: [Jprogramming] an improvement to apply and perhaps anon evoke >> >> I have used similar tools for related purposes before; nowadays I use the >> word-from-linear (104!:1) extension. It is not a secret that I have an >> aversion to explicit definitions; one reason is that they change the >> context: >> >> wl=. 104!:1 >> eval =: 1 : ' a: 1 : m' >> >> < '@' eval +'/' eval 1 2 3 >> ┌─┐ >> │6│ >> └─┘ >> < '@' wl +'/' wl 1 2 3 >> ┌─┐ >> │6│ >> └─┘ >> >> So far, so good; however, >> >> @u >> @u >> '@u'wl >> @u >> '@u'eval >> @a: >> >> PS. Apply (128!:2) only can refer to a verb that take a single argument, >> and J verbs can take only one or two arguments. I regard both situations >> as very minor annoyances. It is not difficult to circumvent this >> “limitation” of apply (and, of course, J verbs can take virtually several >> arguments), for example, >> >> 2 ('+/' apply ,) 3 >> 5 >> >> PPS. For the record: perhaps apply (128!:2) should not produce adverbs or >> conjunctions (or verbs); but, it can. >> >> >> >> >> >> >> On Sat, Apr 5, 2014 at 1:26 PM, Pascal Jasmin <[email protected] >> >wrote: >> >> > apply does not work with dyadic verbs, and cannot produce modifiers. >> > Consider the following simple looking eval function. >> > >> > eval =: 1 : ' a: 1 : m' >> > >> > >> > 2 '+' eval 1 2 3 >> > 3 4 5 >> > >> > >> > + '/' eval 1 2 3 >> > 6 >> > >> > >> > >> > '+/' eval(+:@) 1 2 3 >> > 12 >> > >> > >> > +:@+'/' eval 1 2 3 >> > 22 >> > >> > >> > +: +'/' eval 1 2 3 >> > 12 >> > >> > >> > (+: '@' eval +)'/' eval 1 2 3 >> > >> > 22 >> > >> > +: '@' eval +'/' eval 1 2 3 >> > 12 >> > >> > >> > The last statement is interesting because it seems to alter the normal >> > conjunction train processing (sometimes in desirable ways) >> > >> > instead of just grabbing a single token as v. >> > >> > < '@' eval +'/' eval 1 2 3 NB. would be domain error without '@'eval >> > ┌─┐ >> > │6│ >> > └─┘ >> > >> > >> > eval is the key to how my multiline tacit code works: >> > >> http://www.jsoftware.com/jwiki/PascalJasmin/Multiline%20tacit%20expressions%20with%20macros >> > ---------------------------------------------------------------------- >> > For information about J forums see http://www.jsoftware.com/forums.htm >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm >> > > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
