Re: emacs master + org Wrong type argument: number-or-marker-p

[Alan Mackenzie]

Hello, Eli.

On Tue, Aug 02, 2022 at 16:46:24 +0300, Eli Zaretskii wrote:
> > Date: Mon, 1 Aug 2022 20:05:44 +0000
> > Cc: Mattias Engdegård <mattiase@acm.org>,
> >  Eli Zaretskii <eliz@gnu.org>, philipk@posteo.net, silent2600@gmail.com,
> >  emacs-devel@gnu.org
> > From: Alan Mackenzie <acm@muc.de>

> > I see in

> >     commit 9d8a6c82838f2f24e76a67379b02956aa668d7cf
> >     Author: Gregory Heytings <gregory@heytings.org>
> >     Date:   Mon Aug 1 19:11:01 2022 +0000

> > the following text:

> >     +Note that, in rare circumstances, Emacs may decide to leave, for
> >     +performance reasons, the accessible portion of the buffer unchanged
> >     +after a call to @code{narrow-to-region}.

> > You cannot do this.  narrow-to-region and widen aren't nice-to-have
> > optional extras, they are essential parts of program functionality.  If
> > you stop them working properly, programs will break.  It is a bit like
> > the Lisp machine randomly failing to perform some car operations.

> This happens only in buffers with very long lines, where we want to
> prevent Lisp programs called from low-level facilities, like
> redisplay, to scan the entire buffer.

So Lisp programs will "only" fail to work in buffers with long lines.  I
protest at this.  There surely could have been a solution to whatever
the problem was that respected the integrity of the Lisp machine.  There
is not even a return code to say that a byte-code instruction has failed
to work.  Surely there should be an error signalled if such happens,
since the program is broken after ignoring an instruction.

Ignoring what a programmer programmed cannot be a good strategy.

> "Normal" invocations from Lisp will not meet with this.

A great deal of pain is fore-ordained.

I protest also that this wasn't discussed openly on emacs-devel.

> > Would it also be possible to add in some commentry motivating this
> > unusual action?

> I added some verbiage.

Thanks.

-- 
Alan Mackenzie (Nuremberg, Germany).