I was sending calcic2.ijs to you as a pm, Ric, but then thought the forum ought to be brought in.
But having uploaded it to the JinaDay page, like you were doing, I simply forgot to detach the attachment. Looks like Bill has put his finger on it. I guessed it had something to do with deferred definition. It worried me that typing this into IJX... plus=: + in executed 'in' at assignment time, not when 'plus' was run by the handler. (Maybe this part of the discussion should be moved to Programming forum?) Umm... I don't think this is an area I want to get into, except as part of a masterclass. Something for JtheMorningAfter. Certainly not in a peace-offering to unregenerate APLers, who won't need much convincing that J is touchy where adverbs are concerned. NOt the message I want to send. How to finesse this in JinaDay? Ought I to say? ... "Don't push the gui too hard, to make it read your mind." (...viz. that 'in' is going to be defined later as an adverb, not a verb) "With enough explicitly-defined cover functions you can get round most problems, 'cos those bind at execution time." "Only assign safe monadic verbs to handlers, until you know what you're doing" (...like I dont, lol) Or ought I to shut the door on the whole topic -- and not provoke novices with code teetering on the brink of complex issues? I do so want to give a natural-looking example where a user-defined adverb would really be useful, and invoke it tacitly, to show APLers there's nothing to be afraid of. Ian On Wed, Nov 3, 2010 at 8:51 AM, Sherlock, Ric <[email protected]> wrote: > Ian, > > I was surprised when I saw your attachment in the forum, I had thought that > the forum didn't accept them. Doesn't look like it accepted mine. I will send > it to you directly. > Ric > >> -----Original Message----- >> From: [email protected] [mailto:general- >> [email protected]] On Behalf Of Sherlock, Ric >> Sent: Wednesday, 3 November 2010 21:30 >> To: General forum >> Subject: Re: [Jgeneral] "J In A Day" --crits please >> >> I think Bill is right, >> Options are to make sure adverb definition is before tacit handler >> definition or make the handler definition explicit. The attached shows >> both approaches. >> >> Also: >> Seems that acc should be ACC to be consistent with NEWNUMBER . >> Moved initialization of ACC and op to clr . >> Seems pointless to bind numeric digits to digit and convert them to >> character. >> 8!:2 automatically converts _ to - . >> >> >> >> > From: Ian Clark >> > Sent: Wednesday, 3 November 2010 15:59 >> > >> > Hi Ric, >> > >> > Thanks for helping to extend calc.ijs. >> > I've been developing in parallel with yours, but have raided some of >> > your verbs, which are neater than mine. The result is uploaded same >> > place as yours (attachments: JinaDay) as: calcic2.ijs >> > >> > It has a full range of + - * / buttons, implemented with (verb): >> > setop, which I feel is a little clunky. Out of interest I've tried a >> > neater alternative, an adverb called: in, so I can use +in, -in, etc. >> > It would be a nice demo of adverbs returning verbs. But I think I've >> > hit a J bug... >> > >> > This works fine: >> > calc_times_button=: doit >> > >> > ...where doit is defined, as in the script, _after_ the definition >> of: >> > in as: >> > doit =: *in >> > >> > But this doesn't (it upsets the gui somehow): >> > calc_times_button=: * in >> > >> > Nor does this: >> > doit =: *in >> > calc_times_button=: doit >> > >> > Can you see what I'm doing wrong? I can't. >> > >> > Ian >> > >> > >> > On Wed, Nov 3, 2010 at 1:10 AM, Sherlock, Ric >> > <[email protected]> wrote: >> > > Further update to calc2.ijs: >> > > >> > > Altered button order/layout. >> > > >> > > Moved NEWNUMBER=: 1 to update rather than repeating in each >> operation >> > button. >> > > >> > > Ends up highlighting another gotcha for new users: >> > > If you define a verb whose result is a verb, adverb or conjunction >> > then J will report a syntax error when the verb runs. If no result is >> > required then a common solution is to add an extra line that returns >> > "empty" (i.0 0) >> > > >> > >> From: Sherlock, Ric >> > >> Sent: Wednesday, 3 November 2010 12:55 >> > >> >> > >> Yes, when I got around to testing in a clean session I had noticed >> > that >> > >> too. >> > >> The latest version on the wiki initializes them. >> > >> >> > >> > From: Ian Clark >> > >> > Sent: Wednesday, 3 November 2010 12:52 >> > >> > >> > >> > I get value errors for op and acc on starting up, unless I >> > initialise >> > >> > them in calc_run. >> > >> > >> > >> > On Tue, Nov 2, 2010 at 9:55 PM, Sherlock, Ric >> > >> > <[email protected]> wrote: >> > >> > > I've made some more "improvements" to calc2.ijs. Includes "-" >> > >> button. >> > >> > > Adding additional operations should be trival. >> > >> > > Renamed the verb "clear" to "clr" so that clear_z_ is still >> > easily >> > >> > useable. >> > >> > > >> > >> > > I use the TortoiseMerge app to do diffs between similar >> versions >> > of >> > >> a >> > >> > script. I'm sure you have your own favourite. >> > >> > > >> > >> > > Ric >> > >> > > >> > >> > >> From: Of Ian Clark >> > >> > >> Sent: Tuesday, 2 November 2010 17:12 >> > >> > >> >> > >> > >> Thanks for calc2, Ric. >> > >> > >> >> > >> > >> I'll have to study it closely because it's much like my own >> > >> > extension, >> > >> > >> but not exactly so. >> > >> > >> >> > >> > >> I also feel that buttons for the remaining ops are needed >> now, >> > and >> > >> > >> that this needn't complicate the demo too much. In fact with >> > the >> > >> use >> > >> > >> of 'bind' (and I was confusing 'bind' and Bond but you didn't >> > say >> > >> > >> anything) my demo has become if anything too simple to >> > illustrate >> > >> > what >> > >> > >> I originally wanted to. >> > >> > >> >> > >> > >> Ian >> > >> > >> >> > >> > >> >> > >> > >> On Tue, Nov 2, 2010 at 2:15 AM, Sherlock, Ric >> > >> > >> <[email protected]> wrote: >> > >> > >> >> From: Ian Clark >> > >> > >> >> Sent: Tuesday, 2 November 2010 09:33 >> > >> > >> >> >> > >> > >> >> > I agreed with Brian that I missed the "equals" button in >> > the >> > >> > >> original >> > >> > >> >> calc.ijs. Now I miss the "plus" button. It seems >> unintuitive >> > to >> > >> > >> press >> > >> > >> >> "=" when you want to add. >> > >> > >> >> >> > >> > >> >> Hahaha! (Can't please everybody.) Can I interest you in a >> > more >> > >> > >> >> advanced calculator? It's called J ... :-) >> > >> > >> >> >> > >> > >> >> I'm just glad I wasn't on the design team of the original >> > >> pocket >> > >> > >> >> calculator. It's subtler than it looks. >> > >> > >> >> >> > >> > >> >> Providing both '+' and '=' buttons means adding a whole >> row >> > or >> > >> > >> column >> > >> > >> >> of buttons or it looks untidy. I've a calc with the >> > >> conventional >> > >> > >> >> look'n'feel -- but IMO it's too complex to serve as a good >> > >> demo. >> > >> > >> >> >> > >> > >> > >> > >> > >> > I've attached an alternative layout to the JinaDay wiki >> page >> > >> > (named >> > >> > >> calc2.ijs) that includes separate '=' and '+' buttons. There >> > are >> > >> > also >> > >> > >> some minor changes to some of the verbs to make it work more >> > like >> > >> my >> > >> > >> calculator and make it easier for users to add other >> operation >> > >> > buttons. >> > >> > >> See if you think that works/looks OK. >> > >> > >> > >> > >> > >> >> > The current phrasing of your "blasphemous comment" has >> > more >> > >> > impact >> > >> > >> >> but I get the feeling that your actual message is more >> like: >> > >> > "There >> > >> > >> is >> > >> > >> >> no need to get your head around tacit definition". The >> fact >> > is >> > >> > that >> > >> > >> >> many of the button handlers in the calc script use tacit >> > code! >> > >> I >> > >> > >> >> suppose it comes down to whether you think that being >> > >> provocative >> > >> > >> >> rather than reassuring will help get your message across >> > best. >> > >> > >> >> >> > >> > >> >> "Here Be Dragons..." >> > >> > >> >> >> > >> > >> >> I meant to be reassuring by being provocative. Reassuring >> > (to >> > >> > >> APLers) >> > >> > >> >> by being (or, rather, risking being) provocative to J-ers. >> > >> > >> >> >> > >> > >> >> De-mystifying a topic is never free from the insinuation >> > that >> > >> the >> > >> > >> >> mystery is intentional: or at the very least, serving >> > someone's >> > >> > >> >> purpose. People are quite smart, you know. If a mystery >> > serves >> > >> no >> > >> > >> >> purpose -- or no one's purpose -- it soon gets cleared up. >> > It >> > >> > >> follows >> > >> > >> >> that de-mystification is apt be viewed as de-bunking. >> > >> > >> >> >> > >> > >> >> It wasn't my intention to debunk. Simply to cast some >> light. >> > >> > Maybe >> > >> > >> to >> > >> > >> >> let in some fresh air. >> > >> > >> >> >> > >> > >> >> On first encountering APL my initial response was to feel >> > >> > >> inadequate. >> > >> > >> >> I should have felt humble, but instead I felt humiliated. >> > >> Because >> > >> > at >> > >> > >> >> the time I was masquerading as a "computer scientist", ie >> an >> > >> > expert. >> > >> > >> >> This was back in 1973, when the industry was less >> > fragmented. >> > >> It >> > >> > was >> > >> > >> >> "IBM and the Seven Dwarfs" -- and I was IBM. >> > >> > >> >> >> > >> > >> >> So I looked for holes. For excuses to label APL as mad, >> not >> > >> > >> brilliant. >> > >> > >> >> Then I'd be exposed as sane, not stupid. It reassured me >> to >> > >> swap >> > >> > sly >> > >> > >> >> remarks about the language, especially as others felt the >> > same >> > >> as >> > >> > I. >> > >> > >> >> >> > >> > >> >> On first encountering J, I experienced the selfsame >> feeling >> > I >> > >> had >> > >> > on >> > >> > >> >> first meeting APL. It largely revolved around "tacit >> > >> > programming". >> > >> > >> >> Attempts by those who'd Seen The Light to motivate me by >> > saying >> > >> > >> "it's >> > >> > >> >> really quite easy" -- or -- "it's far better than APL >> doing >> > it >> > >> > this >> > >> > >> >> way" simply provoked hostility. And not just in me, I >> > observed. >> > >> > >> >> >> > >> > >> >> So there was a barrier to surmount, before I could >> > contemplate >> > >> J >> > >> > >> >> equably, let alone consider using it myself for a serious >> > task. >> > >> > >> >> >> > >> > >> >> Tacit programming _isn't_ "really quite easy". In >> principle, >> > >> > >> maybe... >> > >> > >> >> But in practice it's as much a strain as coding in 68000 >> > ASM. >> > >> > (Yes, >> > >> > >> >> done that -- and sold the result). >> > >> > >> >> >> > >> > >> >> And that, I think, is the way to look at it. Those who can >> > do >> > >> it >> > >> > can >> > >> > >> >> justly be proud of their skill. But nobody is ashamed of >> not >> > >> > being >> > >> > >> >> able to compose 68000 machine code in their heads without >> > >> > computer >> > >> > >> >> assistance, so why should they be when it's tacit J? >> > >> > >> >> >> > >> > >> >> There is this difference. Machine-code is best kept >> beneath >> > the >> > >> > >> >> covers. But tacit J beneficially seeps out. As you >> observe, >> > >> > there's >> > >> > >> >> tacit code in calc.ijs. >> > >> > >> >> >> > >> > >> >> IMO the issue over tacit J is not whether we should banish >> > >> > (digit&1) >> > >> > >> >> from calc.ijs, but whether we should aim to make novices >> > >> ashamed >> > >> > of >> > >> > >> >> writing: >> > >> > >> >> quo=: 3 : 'Q,(":>y),Q' NB. place datum in quotes >> > >> > >> >> instead of: >> > >> > >> >> quo=: Q , Q ,~ [: ": > >> > >> > >> >> because that, I think, has been counter-productive. >> > >> > >> >> >> > >> > >> >> They'll do so in the end... and like as not they won't >> know >> > >> > they're >> > >> > >> >> doing it. >> > >> > >> > >> > >> > >> > I agree that it is counterproductive to denigrate the use >> of >> > >> > explicit >> > >> > >> definition. I don't think that happens really, although I >> know >> > >> that >> > >> > a >> > >> > >> lot of code on the forums is tacit. As I said recently on >> > >> > comp.lang.apl >> > >> > >> I think this is really just a side effect of more experienced >> > >> users >> > >> > >> thinking and working more in tacit mode. >> > >> > >> > >> > >> > >> > I remember when I started learning J that I pretty much >> > >> "ignored" >> > >> > >> trying to create tacit verbs - I was content to stick with >> > >> explicit. >> > >> > I >> > >> > >> found the tacit code on the forum hard to read/understand. I >> > think >> > >> > my >> > >> > >> biggest hurdle in coming to terms with tacit was being able >> to >> > >> > reliably >> > >> > >> identify the parts of speech for J's various primitives (verb >> > vs >> > >> > adverb >> > >> > >> vs conjunction). Without that knowledge it is hard to >> identify >> > the >> > >> > >> composed verbs and correctly separate the hooks from the >> forks. >> > As >> > >> I >> > >> > >> learnt the J primitives and their parts of speech, suddently >> > tacit >> > >> > >> didn't seem so hard after all, and now I find myself using it >> > in >> > >> > >> preference to explicit for many sentences. >> > >> > >> > >> > >> > >> > Having said that I'd be more inclined to promote the use >> this >> > >> form >> > >> > >> than the one liner string form above. Otherwise things can >> get >> > >> messy >> > >> > >> when dealing with strings. >> > >> > >> > quo=: 3 : 0 >> > >> > >> > Q,(":>y),Q >> > >> > >> > ) >> > >> > >> > >> > >> > >> > Ric >> > >> > >> > ----------------------------------------------------------- >> -- >> > --- >> > >> -- >> > >> > --- >> > >> > >> - >> > >> > >> > 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 >> > > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
