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From: Eli Zaretskii <eliz@gnu.org>
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Subject: Re: unwind-protect within while-no-input
Date: Wed, 08 May 2024 21:51:34 +0300
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To: Spencer Baugh <sbaugh@janestreet.com>
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> From: Spencer Baugh <sbaugh@janestreet.com>
> Date: Wed, 08 May 2024 11:14:05 -0400
> 
> If I have a function:
> 
> (defun my-function ()
>   ...do something...)
> 
> which might be invoked by some other package that I don't control like this:
> 
> (defun some-other-package ()
>   (while-no-input
>     ...
>     (my-function)
>     ...))
> 
> How does my-function run the unwind-forms when it is interrupted by
> while-no-input?

How can a function cause its caller to do anything at all?  It can't.
If the caller wants to make sure some unwind-forms will always run
after my-function either returns locally or exits non-locally, the
caller needs to arrange for that.