Re: help in writing function to pop indirect buffer

[Luca Ferrari <fluca1978@gmail.com>]

On Tue, Jan 31, 2023 at 8:39 AM Jean Louis <bugs@gnu.support> wrote:
>
> * Luca Ferrari <fluca1978@gmail.com> [2023-01-30 16:31]:
> > On Sat, Jan 28, 2023 at 12:51 PM Bruno Barbier <brubar.cs@gmail.com> wrote:
> > > In your use case, it might not be possible to use indirect buffers: the
> > > base buffer and the indirect buffer share the same text and its
> > > properties, and, syntax highlighting is mostly done using text
> > > properties.
> > >
> >
> > Gosh!
> > I've tested that if I enable cperl-mode in the original buffer, then
> > the indirect buffer inherits the syntax highligthing also for new
> > code.
>
> I gave you reference:
>
> EmacsWiki: Indirect Buffers:
> https://www.emacswiki.org/emacs/IndirectBuffers
>
> Where it says:
> --------------
>
> It seems one can also set the mode from a fake buffer-file-name (using
> auto-mode-alist in the usual way). At least with Emacs v20. So a
> fake-file-name of say “x.el” will result in emacs-lisp-mode.

I had some time to try over again, and apparently this is working fine:

 (defun plperl-indirect-buffer-editing ()
  (interactive)
  (let ((plperl-buffer-mode 'cperl-mode)
(plperl-buffer (make-indirect-buffer (current-buffer) "indirect.pl"))
    (start (if mark-active (min (point) (mark)) (point)))
    (end   (if mark-active (max (point) (mark)) (point))))
    (pop-to-buffer plperl-buffer)
    (funcall plperl-buffer-mode)
    (font-lock-mode)
    (narrow-to-region start end)
    (goto-char (point-min))
   (shrink-window-if-larger-than-buffer)))

Note that without the funcall plperl-buffer-mode and without adding
the fake extension to the buffer name, the perl mode is not selected.
I'm not fully satisfied however, I need to work on this a little more.

Thanks,
Luca