DIETER ENSSLEN wrote:
> 26 years of reverse progress, you should see how
> elegant and simple this all is in about 1984 BASIC
J is not a calculator.
J is not a computer algebra system.
J is not designed for primary development on a handheld device.
J can be used for all those purposes, and indeed offers some wonderful
advantages for those purposes, but if those are your only
purposes, then J is not right for you.
J has a lot to offer, as you can see by the amount of traffic on this list, but
by focusing on only those purposes, you are missing
out on that.
My recommendation is to learn J for what it is, and then apply that knowledge
to make it what you want it to be.
For example, J does not have native hashes (that's not "what J is"), but I was
able to knock together a script that provides them
in literally 5 minutes (but I was able to apply my knowledge to "make it what I
want it to be").
> still no advice on how to list an edited program
You lament the lack of concrete advice: I think the problem is we're shy of
giving it, because we've tried to do so before, and we
can't seem to present it in a way that helps you. This may have multiple
causes, but I suspect we'll communicate better with more
information.
So, for example, if you want concrete advice on "how to list a freshly edited
program", then describe the concrete steps you're
taking to edit a program, and concretely what you want to see and how.
For example, you could describe your problem thus:
(1) On my desktop, which is running Windows XP, I click on
Start>Program Files>J602>J (blue icon)
(2) I click on "File", then "Recent", then I select a script
(3) A new script window (IJS) pops up
(4) I edit its contents with the keyboard, deleting and adding lines
(5) I press the combination key CTRL+W
(6) In the session manager, I see a line like "load 'myscript.ijs'",
and the smoutput of my script (if any).
(7) I would also like to see the lines that produced that output.
In this case, I could advise you to press CTRL+SHIFT+W instead of just CTRL+W.
Or, you could write:
(1) On my handheld, which is a FooMaster 2600, I use the file explorer
to navigate /Foo/bar, and there I double-click the
blue "J" icon
(2) This is the same icon the Forum helped me install and identify a
couple weeks back
(3) J pops up, and shows me an interactive prompt.
(4) Using the built-in keyboard on my FooMaster, I can type lines into
this prompt and get answers back, as with a
calculator. I type 1+2, I get 3
(5) I load a script by using my stylus and clicking on "this", then
"that", then "something else"
(6) My script defines the verb "fib", which takes a scalar integer
input N and produces the vector of the first N Fibonacci
numbers as output
(7) I realize I want to start at 0 1, not at 1 1.
(8) So, using the built in keyboard on my FooMaster, I type f1b=:
{.@($:&0 1x) : ((<:@[ $: +/\@|....@])^:(*...@[)) .
(9) I would like to see J confirm this change by printing out the new
version of fib .
In this case, I could advise you to simply type the word "fib", and press enter.
I doubt either of these cases represent your difficulty, because there is no
need for J to list the freshly-edited program, given
that you're looking at it in either case (in case 1, the freshly-edited program
is the file you're in when you're pressing
CTRL+SHIFT+W, in the second case, the freshly-edited program is the line with
the assignment you just typed in, and are staring at).
But I hope it demonstrates how the more concrete you are, the more concrete we
can be. I simply will not be able to help you
further if you reply to this message in short, general terms, especially if you
neglect to include context by copy/pasting from this
message (not the whole thing, just the relevant parts you're referring to).
> i have tried to keep some of the fellow J ers on topic
Kettle? Kettle is that you?
-Dan
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