GNU bug report logs - #73886
29.4; Confusing info about void function cells in Emacs Lisp manual

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Message #34 received at 73886-done <at> debbugs.gnu.org (full text, mbox):

From: Eli Zaretskii <eliz <at> gnu.org>
To: Ulrich Müller <ulm <at> gentoo.org>
Cc: monnier <at> iro.umontreal.ca, 73886-done <at> debbugs.gnu.org
Subject: Re: bug#73886: 29.4; Confusing info about void function cells in
 Emacs Lisp manual
Date: Sun, 27 Oct 2024 16:08:23 +0200

> From: Ulrich Müller <ulm <at> gentoo.org>
> Cc: Stefan Monnier <monnier <at> iro.umontreal.ca>,  73886-done <at> debbugs.gnu.org
> Date: Sun, 27 Oct 2024 14:40:36 +0100
> 
> >>>>> On Sun, 27 Oct 2024, Eli Zaretskii wrote:
> 
> > Thanks, I've now updated the documentation, and I'm closing this bug.
> 
> TBH, I find the new wording still confusing: "It is impossible to
> distinguish between a function cell that is void and one set to nil."
> After commit eadf1faa3cb5eea8c25a5166a9a97ebd63525c56 there are no void
> function cells any more.

A function that was not defined at all is void.

> They start out as nil and they always contain a lisp object.

That's an implementation detail.  The ELisp manual does not describe
the implementation, not on such a low level.  The previous text didn't
mention the implementation (the special symbol 'unbound') either.

> So, differentiating between nil and void in the manual seems a
> little artificial.

Which is what the text now says.

> Also, there is the following paragraph in symbols.texi which probably
> should be updated (regardless of what I said above):

Thanks, fixed.

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