Correction for the second. @. (dyad) can replace ^: (dyad) which can replace | (monad).
I didn't think that through very well! On 12 Feb 2016 12:49 pm, "Matthew Baulch" <[email protected]> wrote: > If I understand correctly, the result of 0 : 0 may be referenced as any > part of the expression on the same line; whether before, or indeed AFTER > the 0 : 0. Conceptually, the lines following 0 : 0 (until the terminating > ')') can be regarded as embedded in the 0 : 0 within the sentence. This is > a curious design decision, but I think I understand how it works. (As noted > to Henry, I'm not convinced it's adequately documented) > > Regarding the 'heavy-handed' comment, I was just pointing out that ". is a > very powerful, arguably the most powerful, verb. We are using it for a > minor syntactic effect: nothing else. > > Analogously, ^: can replace +, which can replace >: (all dyadic). > Similarly, @. can replace ^:, which can replace -. (dyadic here too). For > code with maximum clarity, the 'least powerful' or 'most specific' > verb/conjunction/... suitable for a task is most often preferred as it > usually leads to the clearest code. > On 12 Feb 2016 4:38 am, "Raul Miller" <[email protected]> wrote: > >> [posting my response in-line for context] >> >> On Thu, Feb 11, 2016 at 12:55 AM, Matthew Baulch <[email protected]> >> wrote: >> > Thanks everyone. This (let's say) creative use of 0 : 0 makes sense to >> me >> > now. I wonder if it's an accidental consequence of the implementation >> that >> > allows an expression following the 0, or whether it's a deliberate >> design >> > decision. Either way, it makes sense to have it documented. Can't see >> it in >> > NuVoc or the Dictionary. Of course, I may have overlooked it. >> >> http://www.jsoftware.com/help/dictionary/d310n.htm says >> 0 : n noun >> >> So the result of 0 : 0 is a noun. (Specifically, it's a list of >> characters.) So you should expect that anything you can do with a noun >> you can do with a noun produced by 0 : 0 >> >> Or, that's how I read it... >> >> Note also that you can have multiple explicit definitions on the same >> line. They pull their scripts from the input stream in the order that >> they are parsed (mostly that's right-to-left). This can be fun to play >> with, sometimes, but I guess it's usually better to give scripts >> names. >> >> > Honestly, to obtain something simple like multi-line noun definitions, >> ". >> > does seem like quite a heavy-handed tool. It does work however, so I >> > probably shouldn't grumble. >> >> I'm not sure why you say that. >> >> One possibility is that ". cannot produce adverb or conjunction >> results. (If that is the issue, you can resolve it by moving the >> assignment statement inside the explicit noun.) >> >> Another possibility is that you would prefer a more heavy handed >> approach (for example, moving an "ignore end of line" implementation >> inside the interpreter and then changing other aspects of the >> interpreter to taste.) >> >> But it's even more likely that I'm simply not following your thought >> process. Would you care to elucidate? >> >> 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
