RE: How can I discover group name?

[Drew Adams <drew.adams@oracle.com>]

> >> Within "M-x customize"  I found "Text" group.
> >
> > I don't see that group, with `emacs -Q'.  Perhaps it comes from
> > some library that you are using?
> >
> > What does `M-x customize-group RET TAB' tell you?
> > That's how to discover group names.
>
> M-x customize RET
> 
>   Emacs group: Customization of the One True Editor.
>          State : visible group members are all at standard values.
>         See also Manual.
> 
>   Editing		    Basic text editing facilities.
>   Convenience		    Convenience features for faster editing.
>   Files		    Support for editing files.
>   **Text**	    Support for editing text files.
>   ...

Oops.  Looks to me like a bug (#24549) that `M-x customize-group'
does not recognize custom group `text'.

> Under "Text" group (if press RET on **Text**):
> 
>   Text group: Support for editing text files.
>          State : visible group members are all at standard values.
> 
>   Show Value Text Mode Hook
>      Hook run after entering Text mode. More
> 
>   Subgroups:
>   Bib		    Major mode for editing bib files.
>   Columns		    Prettify columns.
>   Lpr		    Print Emacs buffer on line printer.
>   Nroff		    Nroff mode.
>   Outlines		    Support for hierarchical outlining.
>   Picture		    Editing text-based pictures ("ASCII art").
>   ...
>   Rst		    Support for reStructuredText documents.
>   Table		    Text based table manipulation utilities.
>   Tex		    Code related to the TeX formatter.
>   Tildify		    Add hard spaces or other text fragments to text
> buffers.
>   View		    Peruse file or buffer without editing.
> 
> Within 'M-x customize-group RET TAB' I didn't see either "text" nor
> "Text".

Me neither.  I just filed bug #24549 for this.

> >> I'd like to add my group to this group. Unfortunately this was failed:
> >>   (defgroup xxx nil
> >>     "xxx-mode customization."
> >>     :group 'text)
> >               ^^^^  'Text, not 'text, if "Text" is the group name.
> >
> >> Searching around gave working piece:
> >>   (defgroup xxx nil
> >>     "xxx-mode customization."
> >>     :group 'wp)
> >>
> >> How can I guess "wp" name from customize buffer content?
> >
> > What is the relation between this and group "Text"?
> > What do you see in the Customize buffer?
> 
> Screens shown above. After executing:
> 
> >>   (defgroup xxx nil
> >>     "xxx-mode customization."
> >>     :group 'wp)
> 
> I see my group under Text group:
> 
>   Text group: Support for editing text files.
>          State : visible group members are all at standard values.
> 
>   Show Value Text Mode Hook
>      Hook run after entering Text mode. More
> 
>   Subgroups:
>   Bib		    Major mode for editing bib files.
>   View		    Peruse file or buffer without editing.
>   ...
>   Xxx		    xxx-mode customization.
> 
> ================================================================
> 
> My question is why does "Text" group require symbol 'wp' in "(defgroup
> ...)"
> call and how can I guess this symbol during navigation across *Customize*
> buffers?

Good question.  I'm getting the impression that `text' is not
a real group but is some other kind of (virtual) grouping of
some other groups.

I do not see it defined in the Lisp sources using `defgroup'.
If it were defined using `defgroup', as usual, then I would
expect that (1) you would be able to inherit from it directly
and (2) it would be recognized by `customize-group'.

> I discover proper name only after:
> 
>   $ ack -C 5 '(defgroup'  $EMACS_SRC/lisp
> 
>   textmodes/rst.el
>   283-
> 
>   284-(defgroup rst nil "Support for reStructuredText documents."
>   285:  :group 'wp
>   286-  :version "23.1"
>   287-  :link '(url-link "http://docutils.sourceforge.net/rst.html"))