Re: Customizing faces with `defcustom'

["Richard M. Stallman" <rms@gnu.org>]

    Consider, for example, the customization buffer for `matching':

[Made by M-x customize-group RET matching RET]

    (1) `match' stands out in `custom-face-tag-face', by default scaled by
	 1.2 and bold.

    (2) `list-matching-lines-default-context-lines' is highlighted in
	 `custom-variable-tag-face', by default scaled by 1.2 and bold.


    Then come the options

    (3) `list-matching-lines-face' and
	 `list-matching-lines-buffer-name-face' both in default face.

That is a real bug.  These are variables, and their names should be
highlighted like all other variable names.

I think this is a consequence of the following definition for
widget type `face'.

    (define-widget 'face 'symbol
      "A Lisp face name (with sample)."
      :format "%t: (%{sample%}) %v"
      :tag "Face"
      :value 'default
      :sample-face-get 'widget-face-sample-face-get

I think that this :sample-face-get definition is affecting the
appearance of the variable's name.  The code in the definition of the
`face' widget was adapted from the `color' widget.  I tried this
example

    (defcustom foocolor "black"
      "Foo"
      :type 'color)

and saw the same problem occur.

I think it is a bug that the :sample-face-get of the type has an
effect on display of the variable name.  I would expect it to affect
only where the value is displayed.  But I have never understood the
widget code, so I have no idea how this happens.

Can anyone figure out how to fix that?