Subject: bug#43557: 28.0.50; Please document which objects are mutable and which are not

From: Lars Ingebrigtsen <[email-masked]>
Date: Thu, 15 Oct 2020 17:34:41 +0200

Philipp Stephani <[email-masked]> writes:

> The "Mutability" section in the ELisp manual mentions that there are
> mutable and immutable objects, but (besides giving a few examples)
> doesn't document which objects are actually mutable.  At the very least,
> there should be a list of functions that are guaranteed to return
> mutable objects, and a statement about the mutability of function return
> values in general.

Reading the section, it seems pretty clear to me, and outlines the cases
where you can't assume mutability (even if the objects may appear to be
mutable).

I'm not sure a list of mutable objects is a well-defined request, and
there are very few functions that can promise to return a mutable
object.  (I mean, (list 1 2 immutable-list) is mutable, but can contain
elements that aren't.)

So I'm not sure whether what you're requesting is feasible.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no