bug#69305: outline-minor-mode for tabulated-list-mode

[Eli Zaretskii <eliz@gnu.org>]

> From: Juri Linkov <juri@linkov.net>
> Cc: 69305@debbugs.gnu.org
> Date: Sun, 25 Feb 2024 19:25:10 +0200
> 
> >> >> Sorry, I don't understand what is unclear here:
> >> >>
> >> >>   If the value is a list, each list element corresponds to one group, and
> >> >>   should have the form @w{@code{(@var{group-name} @var{entries})}}, where
> >> >>   @var{group-name} is a string inserted before all group entries, and
> >> >>   @var{entries} have the same format as @code{tabulated-list-entries}
> >> >>   (see above).
> >> >>
> >> >> Basically this says that the format is (group-name entries) where
> >> >> entries are described in tabulated-list-entries as having the format
> >> >> (id contents).  There is no need to duplicate the description of entries.
> >> >
> >> > Maybe I'm missing something here.  To put it more concretely, can you
> >> > show a value of tabulated-list-groups that will cause the buffers in
> >> > buffer list grouped by major mode using the above form?
> >>
> >> Data structure for `tabulated-list-groups' is a list of elements,
> >> each element should of the form
> >>
> >>   (GROUP-NAME (ID . CONTENTS) (ID . CONTENTS) ...)
> >>
> >> where GROUP-NAME is the name of the group, ID is a Lisp object that
> >> identifies the entry and CONTENTS is a vector with the same number of
> >> elements as `tabulated-list-format'.  When buffers grouped by major mode:
> >>
> >>   (("* Lisp Interaction" (#<buffer *scratch*> ["." " " "*" #("*scratch*" 0 9 ...) "225" "Lisp Interaction" ""]) ...))
> >
> > This is the value that the user is supposed to supply for the
> > defcustom?  That is, the user must specify all the buffers explicitly?
> > What happens when there's one more buffer in some mode? does the user
> > have then to modify the value of the defcustom?
> 
> This describes the internal data structure, not a defcustom.

Well, my question above, viz.:

>> > Maybe I'm missing something here.  To put it more concretely, can you
>> > show a value of tabulated-list-groups that will cause the buffers in
>> > buffer list grouped by major mode using the above form?

was about the value of this defcustom.  I hoped that by having such a
value as part of this discussion, we will be able to clear any
misunderstandings that could be getting in the way.