I wasn't trying to be skeptical, just ignorant. :) If 1!:0 works reliably except at top-level directories, I could use
1!:5^:(*@#) (#~ [: *./\. 0 = #@(1!:0)"0) <@}:@;\ (<;.2~e.&'/\') ofn which is what you wrote, changed to suit my tastes. But wait, I have another problem. One of the lab chapters is devoted to analyzing this problem. I don't want to make the solution too complicated. Suppose I just delete the first 2 boxes, which are the '\' and the '\disk' levels, and use my original program on the remaining directories. Would that be reliable on Mac? Henry Rich ---- Raul Miller <[email protected]> wrote: > I suggested to Henry that that line should be changed to > > 1!:5(#~ [:*/\.0=#@(1!:0)@>)}:&.>,&.>/\(<;.2~e.&'/\')ofn > > The underlying problems are two: > > [1] J does not have a foreign which tests if a directory exists or > not. (Closest we have to that is 1!:44) > > [2] For some reason getting a listing of the contents of the top level > directories on OSX using 1!:0 fails. > > But 1!:0 works fine on directories which the user owns, so I was > proposing that if 1!:0 worked on any directory that it would be safe > to presume that the directories which contain it also exist. Henry > seemed a bit skeptical of the reliability of that approach. > > A more direct approach might be something like: > > 1!:5@< ::0:@;\(<;.2~e.&'/\')ofn > > In other words: let the create directory command figure out for itself > whether or not the directory exists. > > Thanks, > > -- > Raul > > > On Wed, Jul 8, 2015 at 11:21 AM, robert therriault > <[email protected]> wrote: > > Henry, > > > > Thanks for all the work on the point and click approach to J. > > > > I recently read this blog post by Dan Meyer, a math teacher, who uses the > > analogy of teaching a skill before there is a need to giving the students > > aspirin before they have a headache. It is worth a read for anyone looking > > to change their paradigm of instruction! > > > > http://blog.mrmeyer.com/2015/if-math-is-the-aspirin-then-how-do-you-create-the-headache/ > > > > Also, I have updated jqt via console and made sure all versions of jqt are > > up to date in the pac manager, but I still get > > > > |interface error: opendebscript > > | 0:@(1!:5@<^:(0=#@(1!:0)@}:))@;\(<;.2~e.&'/\')ofn > > > > when I go to step 2 of the 'J by Point and Click 1' lab. Raul mentioned the > > same issue early in this thread, but I have not seen a solution proposed. > > > > I am running > > Engine: j803/2014-10-19-11:11:11 > > Library: 8.04.05 > > Qt IDE: 1.4.2/5.4.2 > > Platform: Darwin 32 > > Installer: J804 install > > InstallPath: /applications/j804 > > > > Any suggestions? > > > > Cheers, bob > > > > On Jul 8, 2015, at 8:00 AM, [email protected] wrote: > > > >> That's what I was trying to say. Make the topic a problem the user cares > >> about solving, so they'll pay attention to the solution. > >> > >> I would guess that a good rule of thumb would be that YOU want to see a > >> solution. You didn't start by saying, "What's something I can do easily > >> in J", but with "What's a problem I'd like to solve?". > >> > >> Henry Rich > >> ---- Devon McCormick <[email protected]> wrote: > >>> I agree with Jon. A lot of NYCJUG's "Beginner's Regatta" modules are > >>> geared toward very basic things like reading file and turning it into a > >>> useful array. > >>> > >>> On Wed, Jul 8, 2015 at 1:56 AM, Jon Hough <[email protected]> wrote: > >>> > >>>> I am interested in contributing, but am unsure what, if anything, I can > >>>> contribute. I'd rather wait to see what others contribute to see what > >>>> kind > >>>> of things you are expecting. > >>>> Regarding your points > >>>> "The main thing is to choose an interesting topic. We want the user to > >>>> see > >>>> the topic as worthwhile, to think about how they would do it in their > >>>> favorite language, and then to see the elegance of the J solution. The > >>>> harder the code is, the farther back it will go into the Lab." > >>>> In my opinion, keeping examples as concrete as possible is best. e.g. > >>>> interfacing with MySQL, a HTTP client, manipulating csv and excel files. > >>>> i.e. things that people are likely to want to use in the real world. > >>>> Things > >>>> like "calculating the square of the sum of the first 100 mersenne primes > >>>> " > >>>> or what not, might put people off and and make J seem only suitable for > >>>> idle mathematical playing. Just a thought. > >>>> > >>>>> Date: Sun, 5 Jul 2015 21:40:39 +0000 > >>>>> From: [email protected] > >>>>> To: [email protected]; [email protected] > >>>>> Subject: [Jprogramming] New visual teaching lab for J - contributors > >>>> needed > >>>>> > >>>>> Up till now, to learn J you had to be willing to read a lot of words. > >>>> Many modern programmers aren't into that. > >>>>> > >>>>> With J8.04, there's a new way - a VISUAL way - to learn J. It uses the > >>>> J IDE, plus debug, dissect, and the user's browser to give an interactive > >>>> environment for exploring J. You can read about this lab at > >>>>> > >>>>> http://www.jsoftware.com/jwiki/JbyPointAndClick > >>>>> > >>>>> (note that you have to update your J8.04 to the level as of right now) > >>>>> > >>>>> As it stands the lab is just a beginning. Load it & see if you like the > >>>> idea. If you do, please contribute a chapter or two. I think about 50 > >>>> more chapters might do the trick. > >>>>> > >>>>> The lab needs material at all levels. Write about a program you find > >>>> interesting and your chapter can be inserted into the lab at an > >>>> appropriate > >>>> place. > >>>>> > >>>>> My hope is that this lab will grow to the point that it can keep a > >>>> scalar programmer's interest long enough for them to see that J is a > >>>> language fit for daily use. Then we can start an outreach program to > >>>> influential codebloggers to get our language the recognition and respect > >>>> it > >>>> deserves. > >>>>> > >>>>> Henry Rich > >>>>> ---------------------------------------------------------------------- > >>>>> For information about J forums see http://www.jsoftware.com/forums.htm > >>>> > >>>> ---------------------------------------------------------------------- > >>>> For information about J forums see http://www.jsoftware.com/forums.htm > >>>> > >>> > >>> > >>> > >>> -- > >>> Devon McCormick, CFA > >>> ---------------------------------------------------------------------- > >>> 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
