How can update assignment be relevant when assigning default values? Thanks,
-- Raul On Tue, Jul 11, 2017 at 9:43 AM, 'Pascal Jasmin' via Programming <[email protected]> wrote: > pretty much any use of =: > > (newrec ;reclookup) update assignwith 'database' > > > > ________________________________ > From: Raul Miller <[email protected]> > To: Programming forum <[email protected]> > Sent: Tuesday, July 11, 2017 9:36 AM > Subject: Re: [Jprogramming] Request for comments: multiple assignment > > > > In what sort of cases are in-place optimizations a relevant issue for > assigning default values? > > Thanks, > > -- > Raul > > > On Tue, Jul 11, 2017 at 9:06 AM, 'Pascal Jasmin' via Programming > <[email protected]> wrote: >> The way I handle that, >> >> assignwithC >> 2 : 0 >> (y) =: u (y~ [ ]) :: (n"_) 1 >> : >> (y) =: x u (y~ [ ]) :: (n"_) 1 >> ) >> >> >> I think the call for =:: and =.. is based on 2 things. >> >> 1. Although defaults and "ORvals"/unassigned default values can be handled >> easily enough through J expressions, for 805 anyway, it lost any inplace >> optimizations. >> >> 2. it only works for =: and not =. >> >> >> >> ________________________________ >> From: Marshall Lochbaum <[email protected]> >> To: [email protected] >> Sent: Tuesday, July 11, 2017 4:02 AM >> Subject: Re: [Jprogramming] Request for comments: multiple assignment >> >> >> Does this scheme support easily assigning a default value to a variable, >> that is, assigning only if the name is currently unused? This is a >> common case for me and I'm just now realizing that the "default" option >> doesn't really do that. >> >> See https://github.com/mlochbaum/JSound/blob/master/wav.ijs for an >> example, where I'm forced to write an awkward line of code to set the >> default format to 16-bit 44.1kHz. This seems easy enough to support with >> another trailing character on the name, like ^ or ?. So I would write >> 'FMT? F?' =: 1 16;44100 >> instead of the current version. >> >> On a side note, Earl Grey is a good language to look at if you are >> interested in more sophisticated assignment schemes. I don't know if >> much of it is relevant to J, but it's very cool to see what can happen >> if you build a language to handle pattern matching from the bottom up. >> See http://www.earl-grey.io/doc.html, up to the section on pattern >> matching. >> >> Marshall >> >> On Tue, Jul 04, 2017 at 01:40:52AM -0400, HenryRich wrote: >>> Here is a feature that I have wanted for a long time: >>> >>> http://code.jsoftware.com/wiki/System/Interpreter/Requests#Expanded_Multiple_Assignment >>> >>> It attempts to solve the problem of moving verb arguments into >>> variable-names. Allows defaults and multilevel arguments. I will implement >>> this within a month or so, so get your comments in ASAP. >>> >>> Henry Rich >>> >>> --- >>> This email has been checked for viruses by AVG. >>> http://www.avg.com >>> >>> ---------------------------------------------------------------------- >>> 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 > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
