Hi Blake,
unfortunately the rules for APL output are such that you cannot "print
as you go".
For example before printing the second item in the first row, the first
column must have
been formatted completely in order to know the width of the first column.
I will see what I can do for aborting the formatting process or the
printout with ^C.
/// Jürgen
On 07/21/2014 11:57 AM, Blake McBride wrote:
Dear Juergen,
I don't think that really solves the problem because:
A. You have to remember to set it - and then to set it only to get
around what amounts to a bug - not being able to hit ^C
B. Whatever you set it to, you still have a problem with lengths that
approach that length.
C. What if you are not in development, the user types a very large
number accidentally in response to a prompt, the program dies and
tries to display the arguments. You end up with a hung program that
no one can interrupt.
I don't understand why you have to format the whole thing before
printing anything (which is what I presume because of the long delay).
Presumably hand-in-hand, I don't understand what you can't catch ^C
there too.
Thanks.
Blake
On Mon, Jul 21, 2014 at 4:47 AM, Juergen Sauermann
<juergen.sauerm...@t-online.de <mailto:juergen.sauerm...@t-online.de>>
wrote:
Hi Blake,
I guess the proposed solution for both was ⎕SYL. Like:
* ⎕SYL[27] ← 10000*
/// Jürgen
On 07/21/2014 12:26 AM, Blake McBride wrote:
Are my two items below a dead issue?
Thanks!
Blake
On Tue, Jul 8, 2014 at 9:58 PM, Blake McBride
<blake1...@gmail.com <mailto:blake1...@gmail.com>> wrote:
I think the layout function need two modifications:
1. enable ^C
2. at least for large data, output as you go rather than
format the whole thing and then output the whole thing
--blake
On Tue, Jul 8, 2014 at 9:27 PM, Elias Mårtenson
<loke...@gmail.com <mailto:loke...@gmail.com>> wrote:
There is already the SIGINT signal which is processed by
GNU APL to interrupt a function execution. However, this
interruptability is not extended to the layout function.
On 9 July 2014 09:09, Peter Teeson
<peter.tee...@icloud.com
<mailto:peter.tee...@icloud.com>> wrote:
In Sharp APL (IPSA) we had a "panic int" which
interrupted whatever was being computed after a
predetermined time.
It was inherent to the interpreter because we ran a
timesharing system.
I don't recall the exact details but it went
something like this;
1) Workspace gets swapped in for execution and is
given a quantum of CPU time
2) At the end of that quantum a second but quite
small (relative to the normal ) additional amount of
CPU was allocated
to see if that would allow an interrupt at a
"suitable" point in the function/operation that was
going on.
3) If that extra time was not sufficient the
workspace was arbitrarily interrupted and AFAICR the
user got )CLEAR WS.
That's probably not exactly correct (I never read the
actual assembly code for that part of the interpreter).
But the idea worked for us.
On a single user system there is no real need for a
specific quantum; the OS takes care of scheduling.
But perhaps a "panic int" concept in some form or
other might be useful?
Perhaps allowing the user to decide if they want to
continue?
Perhaps with a default value? Perhaps assignable by
the user?
respect…
Peter
On 2014-07-08, at 1:50 PM, Blake McBride
<blake1...@gmail.com <mailto:blake1...@gmail.com>> wrote:
> If I do:
>
> z←⍳1000000
>
> the operation is very fast. But if I do:
>
> ⍳1000000
>
> it is very slow, presumably because it is
formatting the whole thing for display. No problem.
>
> The problem is that during its effort to format for
display, I cannot use ^C. ^C appears to work fine in
normal situations - but not during the format for
display time. During format-for-display time ^C is
ignored.
>
> This caused me a problem when I accidentally
mis-typed something. The mis-type caused something
very large to be displayed. In fact, it was so large
that my machine started paging. I was unable to use
^C to stop it. After waiting an hour, I had to kill
the process and loose my work.
>
> Thanks.
>
> Blake
>
