Re: master 67ab357cdcc 7/7: Support treesit-thing-settings in search functions

[Eli Zaretskii <eliz@gnu.org>]

> From: Yuan Fu <casouri@gmail.com>
> Date: Sat, 15 Apr 2023 22:54:29 -0700
> Cc: Po Lu <luangruo@yahoo.com>,
>  emacs-devel@gnu.org
> 
> > Btw, Yuan: any reason you couldn't use the existing assq_no_quit here?
> 
> To be very honest I didn’t know its existence before. But safe_assq is indeed necessary, because assq_no_quit assumes the list is not circular and doesn’t try to detect one.
> 
> For this particular use-case I just don’t want assq to signal any error, but I do want it to detect errors. Circular error, malformed alist, or simply couldn’t find the key, all of these will be reported to the user as “couldn’t find the key” (as an error). This is easier to understand for the user and easier for me to implement (than using unwind-protect and let assq signal).

OK, but please move the safe_assq function (under the name
assq_no_signal, I suggest) to where we have assq_no_quit, and please
explain the difference between them in the commentary.

Thanks.