Ruda wrote
> if I load a (longer) script, I sometimes want to ignore a part of it

I take Ruda's use of "sometimes" to mean he wants the proposed feature to
be switchable.

To anyone wanting to dabble with such a feature, I have a word of advice.
Don't.
If there's part of your script you want to omit, it belongs in a separate
script.
Currently, if you load a J script, it either loads completely or signals an
error. Relax this axiom and you open Pandora's box.

I once implemented a script-truncation feature, along the lines of
   0!:100 < hack fread 'myscript.ijs'
which is very roughly Mike's solution.
I was so taken with it I started using it routinely. Bugs were slow to
appear, but when they did they were destructive and inopportune, usually
unexpected "value errors". And I'd robbed 4!:3 and 4!:4 of their power.

I don't want to discuss here what can go wrong. But if anyone can think
back to punched-card days, IBM gave us these brightly-colored
slash-asterisk cards (if memory serves), to insert in your card deck for
Ruda's purpose. They proved as mischievous as radium toothpaste.

Don't say I didn't warn you.

On Tue, 31 Aug 2021 at 13:27, 'Rudolf Sykora' via Programming <
[email protected]> wrote:

> Dear list,
>
>
> if I load a (longer) script, I sometimes want to ignore a part of it
> beyond a certain line. Is there a way to achieve that gracefully? (I
> sometimes just add something syntactically wrong to stop there, on an
> error).
>
>
> Thank you.
> Ruda
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