I think that it follows the rules of "items". The list of names to the left are considered items and matched with the items on the right of the copula.
On Wed, Jul 12, 2017 at 6:11 PM, Jose Mario Quintana < [email protected]> wrote: > Sure, there are different ways to perform a task, for example, > > 2&* 1 2 3 > 2 4 6 > +: 1 2 3 > 2 4 6 > > What do you mean by "the rest of that"? > > > On Wed, Jul 12, 2017 at 7:40 PM, Raul Miller <[email protected]> > wrote: > > > All [1] needed was > > > > add=:4 :0 > > ((0{::y),'__x')=: ".1{::y > > ) > > > > But I don't really follow the rest of that. > > > > Thanks, > > > > -- > > Raul > > > > > > > > On Wed, Jul 12, 2017 at 7:14 PM, Jose Mario Quintana > > <[email protected]> wrote: > > > The assignments are a consequence of J's agreement; see [0] for > example. > > > If one wants the effect of 'a b c' =:i.3 4 5 using the verb is (or a > > > similar verb) then one can use 'a b c' is i.3 4 5 :) > > > > > > How is 'abc' is"0 i.3 4 5 useful? I do not know... Who knows? > > > > > > How is the verb is (or a similar verb) useful? See [1, 2] for > > instance > > > (not to mention for debugging tacit verbs). > > > > > > References > > > > > > [0] Rank and Uniformity Roger K.W. Hui > > > http://www.jsoftware.com/papers/rank1.htm > > > > > > [1] [Jprogramming] Dynamic Language Features in J? Oleg Kobchenko > > > http://www.jsoftware.com/pipermail/programming/2006- > > December/004479.html > > > > > > [2] [Jprogramming] Saving Nouns as Permanent Data Jose Mario Quintana > > > http://www.jsoftware.com/pipermail/programming/2008- > > April/010529.html > > > > > > > > > > > > > > > > > > On Wed, Jul 12, 2017 at 4:00 PM, Don Kelly <[email protected]> wrote: > > > > > >> How is "is" more useful than from x=: y > > >> > > >> what is interesting is that > > >> > > >> 'abc' is "0 i.3 4 5 displays the i.3 4 5 array but the value of abc > > >> appears as : although a, b, c correspond to > > >> > > >> (<0 1 2; 3; 4){i. 3 4 5 > > >> > > >> 19 39 59 > > >> > > >> > > >> In the use of "is" in this case it appears that it > > >> > > >> > > >> whereas 'abc' =: i. 3 4 5 gives stores the noun abc as the array but > > >> leaves a, b and c undefined > > >> > > >> and 'a b c' =:i.3 4 5 gives 3 (4 by 5 )arrays > > >> > > >> > > >> Don Kelly > > >> > > >> > > >> > > >> On 2017-07-12 11:08 AM, Jose Mario Quintana wrote: > > >> > > >>> Maybe I am misunderstanding... Are you trying to imply that one > cannot > > >>> find a verb such as is=: 4 :'(x)=:y' useful? > > >>> > > >>> > > >>> On Tue, Jul 11, 2017 at 8:37 PM, Raul Miller <[email protected]> > > >>> wrote: > > >>> > > >>> Ok, so, just to be clear - this has nothing to do with default > > assignment? > > >>>> > > >>>> That said, it's probably intentional that there's no verb form of =: > > >>>> (or =.). For example, given > > >>>> > > >>>> is=: 4 :'(x)=:y' > > >>>> > > >>>> consider: > > >>>> > > >>>> 'abc' is"0 i.3 4 5 > > >>>> > > >>>> Questions: > > >>>> > > >>>> (1) what is > > >>>> > > >>>> a+b+c > > >>>> > > >>>> (2) how is this useful? > > >>>> > > >>>> Thanks, > > >>>> > > >>>> -- > > >>>> Raul > > >>>> > > >>>> > > >>>> On Tue, Jul 11, 2017 at 12:53 PM, 'Pascal Jasmin' via Programming > > >>>> <[email protected]> wrote: > > >>>> > > >>>>> Don't fixate on just Henry's syntax or default values. > > >>>>> > > >>>>> The basic "delegated function assignment" is: > > >>>>> > > >>>>> assign =: 4 : '(x) =: y' > > >>>>> > > >>>>> its a verb, that can be composed with others (or rewritten for a > > >>>>> > > >>>> different/enhanced delegated assignment function) in a wide variety > of > > >>>> ways > > >>>> that include all of the discussed applications in this thread. > > >>>> > > >>>>> problem 1: can only use =: not =. > > >>>>> > > >>>>> problem 2: performance issue in any "delegated function > assignment" > > >>>>> > > >>>> that wouldn't (or might not) exist if there were verb (and adverb > > forms I > > >>>> proposed) forms of copula. > > >>>> > > >>>>> I've just repeated previous statements entirely here. Perhaps the > > >>>>> > > >>>> mistake I made was not providing an ideal example to your first > > request. > > >>>> > > >>>>> ________________________________ > > >>>>> From: Raul Miller <[email protected]> > > >>>>> To: Programming forum <[email protected]> > > >>>>> Sent: Tuesday, July 11, 2017 12:37 PM > > >>>>> Subject: Re: [Jprogramming] Request for comments: multiple > assignment > > >>>>> > > >>>>> > > >>>>> > > >>>>> I do not see yet that it would be even possible to do that in a way > > >>>>> that takes advantage of in place assignment optimization. The > default > > >>>>> mechanism only kicks in when no value was being assigned, and it > > seems > > >>>>> to me that cases where you can meaningly have "no value was being > > >>>>> assigned so we need a default" already have complexity which > defeats > > >>>>> the in place assignment optimization. > > >>>>> > > >>>>> Worse, though, is that this does not seem like a common case (which > > >>>>> suggests that it's best not to optimize for it). > > >>>>> > > >>>>> That said, if we're not going to be dealing with code examples > (and I > > >>>>> certainly cannot think of any - the requirements seem > contradictory), > > >>>>> and we are going to continue discussing this, perhaps we should > move > > >>>>> to the chat forum? > > >>>>> > > >>>>> That said, here's a hypothetical non-example based on Henry's > initial > > >>>>> > > >>>> post: > > >>>> > > >>>>> 'L(0)'=: L,y > > >>>>> > > >>>>> For that default value (0) to be relevant, the expression (L,y) > must > > >>>>> be undefined. But if y were undefined the statement would fail with > > an > > >>>>> error. And if y were defined and the statement does not fail with > an > > >>>>> error, then that default of (0) can never be used. > > >>>>> > > >>>>> Which takes me back to my previous thought which was that taking > > >>>>> advantage of in place optimizations for this default seems > > impossible. > > >>>>> > > >>>>> So... once again... what are you talking about? > > >>>>> > > >>>>> Thanks, > > >>>>> > > >>>>> -- > > >>>>> Raul > > >>>>> > > >>>>> > > >>>>> > > > ---------------------------------------------------------------------- > > > 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
