Subject: Re: bug#37337: [PATCH] Fix bug in `TeX-fold-hide-item' when acting on evaporated overlays

From: Florent Rougon <[email-masked]>
Date: Thu, 24 Oct 2019 23:20:03 +0200

Hi Arash,

Arash Esbati <[email-masked]> wrote:

> Many thanks for tracking this down.  I can confirm the bug you describe,
> and have a question reg. your patch: If it's only about checking if
> `overlay-start' and `overlay-end' are non-nil, wouldn't it be easier to
> do:
>
>     (when (and ov-start ov-end) ...)
>
> instead of
>
>     (unless (equal ov-start ov-end) ...)

I don't program in ELisp every day (far from it) but AFAIK, the two
tests are logically equivalent in this context, since the overlay has
the 'evaporate' property. But I guess you already realized that, just
wanted to be clear. So, unless I am mistaken, this is only a matter of
style. I'm quite fine with your test, it puts the emphasis on necessary
conditions for the following code to behave well, I have no problem with
that. :-)

Thanks & regards

-- 
Florent