Re: unwind-protect within while-no-input

[Spencer Baugh <sbaugh@janestreet.com>]

Eli Zaretskii <eliz@gnu.org> writes:
>> From: Spencer Baugh <sbaugh@janestreet.com>
>> Date: Wed, 08 May 2024 09:57:44 -0400
>> 
>> 1. The unwind forms should run if there is a quit, no matter what
>>    triggered the quit.
>> 
>> 2. One thing that might trigger a quit is a while-no-input form outside
>>    my code.
>> 
>> 3. Therefore, the unwind forms should be run even when while-no-input
>>    triggers the quit.
>
> You keep changing the conditions with each solution that people
> propose.  What is the purpose of this "salami-like" way of discussing
> an issue?  Why not state the conditions for the solution you seek
> once, and state them completely, and then let people waste less time
> on trying to help you?

Sorry, it's not intentional - from my perspective I've been asking for
the same thing each time, with all the same details.  But clearly I have
been not fully communicating what I mean.

>> Your code does not run the unwind forms when run inside a
>> while-no-input.
>
> Why should it?  When while-no-input is interrupted by input, it
> conceptually is not "quitting"; the fact that it uses quit-flag is an
> internal implementation detail.

Because there might be something I want to clean up.

For example, my code might create a process or temporary directory which
should be deleted even if interrupted by input.

> If you want the unwind forms to run when while-no-input is interrupted
> by input, simply do it: while-no-input provides a clear documented
> indication that it was interrupted by input, and you can use that to
> decide whether to run the unwind forms in that case.

What concretely are you suggesting?  Could you give an example in code?

Note that my code doesn't require while-no-input or always run inside
while-no-input - it's just that whenever my code happens to be inside a
while-no-input, my code should still do the cleanup.