Re: Listing headings in dedicated buffer with imenu.

[Stephen Berman <stephen.berman@gmx.net>]

On Mon, 29 Jul 2024 11:29:07 +0000 Heime <heimeborgia@protonmail.com> wrote:

> Sent with Proton Mail secure email.
>
> On Monday, July 29th, 2024 at 10:51 PM, Stephen Berman
> <stephen.berman@gmx.net> wrote:
>
>> On Mon, 29 Jul 2024 10:41:08 +0000 Heime heimeborgia@protonmail.com wrote:
>>
>> > Sent with Proton Mail secure email.
>> >
>> > On Monday, July 29th, 2024 at 10:32 PM, Stephen Berman
>> > stephen.berman@gmx.net wrote:
>> >
>> > > On Mon, 29 Jul 2024 10:26:22 +0000 Heime heimeborgia@protonmail.com wrote:
>> > >
>> > > > Sent with Proton Mail secure email.
>> > > >
>> > > > On Monday, July 29th, 2024 at 9:33 PM, Stephen Berman
>> > > > stephen.berman@gmx.net wrote:
>> > > >
>> > > > > On Mon, 29 Jul 2024 08:48:38 +0000 Heime heimeborgia@protonmail.com wrote:
>> > > > >
>> > > > > > I wish to list headings in a dedicated buffer with imenu.
>> > > > > > The listing should be in the order in which headings occur
>> > > > > > in the buffer.
>> > > > > >
>> > > > > > Have done the following, but the buffer ends up empty.
>> > > > > >
>> > > > > > (defun vodil-imenu-bfh ()
>> > > > > > "Insert imenu headings in order in a dedicated buffer."
>> > > > > > (interactive)
>> > > > > >
>> > > > > > (let ((imenu-items (imenu--make-index-alist t))
>> > > > > > (buffer-name "Imenu Headings"))
>> > > > > > (with-current-buffer (get-buffer-create buffer-name)
>> > > > > > (erase-buffer)
>> > > > > > (dolist (item imenu-items)
>> > > > > > (let ((name (car item))
>> > > > > > (position (cdr item)))
>> > > > > > (when (and (stringp name) (number-or-marker-p position))
>> > > > > > (insert (format "%s\n" name)))))
>> > > > > > (goto-char (point-min)))
>> > > > > > (pop-to-buffer buffer-name)))
>> > > > >
>> > > > > It works for me, as long as imenu.el is loaded.
>> > > > >
>> > > > > Steve Berman
>> > > >
>> > > > What would I need to load it ?
>> > >
>> > > One way is this:
>> > >
>> > > (defun vodil-imenu-bfh ()
>> > > "Insert imenu headings in order in a dedicated buffer."
>> > > (interactive)
>> > > (eval-when-compile
>> > > (require 'imenu))
>> > > (let ((imenu-items (imenu--make-index-alist t))
>> > > (buffer-name "Imenu Headings"))
>> > > (with-current-buffer (get-buffer-create buffer-name)
>> > > (erase-buffer)
>> > > (dolist (item imenu-items)
>> > > (let ((name (car item))
>> > > (position (cdr item)))
>> > > (when (and (stringp name) (number-or-marker-p position))
>> > > (insert (format "%s\n" name)))))
>> > > (goto-char (point-min)))
>> > > (pop-to-buffer buffer-name)))
>> > >
>> > > Steve Berman
>> >
>> > Right. I have this function that I run. Running vodil-imenu-bfh
>> > after executing vodil-imenu-expr gives me rescan in the buffer.
>> >
>> > (defun vodil-imenu-expr ()
>> > "Set up `imenu` to show a list of functions in the current buffer."
>> >
>> > (interactive)
>> >
>> > (setq imenu-generic-expression
>> > '( ("headings" "^;;;\\s-+\\([HM][[:digit:]]\\)\\s-+\\(.*\\)" 2)))
>> >
>> > (imenu-add-to-menubar "Iml")
>> > (imenu--make-index-alist t)
>> > (call-interactively 'imenu))
>>
>>
>> What were the contents of the current buffer when you executed
>> vodil-imenu-expr?
>>
>> Steve Berman
>
> I had an elisp file.  I ran "M-x vodil-imenu-expr" when in the file to get
> the correct imenu entries.  But executing "M-x vodil-imenu-bfh" after that
> I end up with the buffer "Imenu Headings" having only *rescan* in it.

When I test your code on one of the built-in Emacs Lisp libraries,
e.g. avoid.el, then, on invoking vodil-imenu-expr, I get prompted for an
Index item, and typing TAB, the *Completions* buffer pops up containing
*Rescan* and nil.  I then type C-g and then M-x vodil-imenu-bfh, and the
*Imenu Headings* buffer pops up containing just *Rescan*.  However, when
I start Emacs -Q, evaluate just my emendation of your vodil-imenu-bfh
command, then visit avoid.el and invoking vodil-imenu-bfh, the
*Imenu Headings* buffer pops up containing this:

*Rescan*
mouse-avoidance-set-pointer-shape
mouse-avoidance-point-position
mouse-avoidance-set-mouse-position
mouse-avoidance-too-close-p
mouse-avoidance-banish-destination
mouse-avoidance-banish-mouse
mouse-avoidance-delta
mouse-avoidance-nudge-mouse
mouse-avoidance-random-shape
mouse-avoidance-ignore-p
mouse-avoidance-banish
mouse-avoidance-exile
mouse-avoidance-fancy
mouse-avoidance-mode

So at least the contents of avoid.el does not contain a match for your
setting of imenu-generic-expression, and presumably the same goes for
the file you tested your code on.

Steve Berman