Re: emacs rendering comparisson between emacs23 and emacs26.3

[Alan Mackenzie]

Hello, Martin.

On Fri, Apr 03, 2020 at 08:59:54 +0200, martin rudalics wrote:

[ .... ]

> 'open-paren-in-column-0-is-defun-start', if non-nil, conceptually allows
> progmodes to avoid scanning an entire buffer in order to get things like
> syntax highlighting and code indenting right.  Rather, progmodes are
> allowed to find the first or next paren in column zero wrt a given
> position and base further decisions on the assumption that such a paren
> is on the "top level" of its buffer.

> Recent Emacsen either ignore that variable or silently reset it to nil
> internally so it doesn't get into their way.

Correction to my recent posts here.  o-p-i-c-0-i-d-s still exists and
can still work.

Currently, its operation is blocked by the variable
comment-use-syntax-ppss being non-nil.  I'm not sure what this variable
is for (it was introduced in:

    commit 14b95587520959c5b54356547a0a69932a9bb480
    Author: Stefan Monnier <address@hidden>
    Date:   Tue Dec 12 23:03:00 2017 -0500

        * src/syntax.c (find_defun_start): Use syntax-ppss

        (syms_of_syntax): New variable comment-use-syntax-ppss.

), but setting it to nil does indeed reenable the o-p-i-c-0-i-d-s
behaviour.  :-)

[ .... ]

> So since you earlier asked for "a switch to turn off the changes" then
> my answer is that such a switch already exists but has been deactivated.

Please try setting comment-use-syntax-ppss to nil.

> martin

-- 
Alan Mackenzie (Nuremberg, Germany).