Subject: bug#35005: 27.0.50; Fontification unexpectedly works with anonymous faces

From: Markus Triska <[email-masked]>
Date: Sat, 09 Nov 2019 18:43:11 +0100

Lars Ingebrigtsen <[email-masked]> writes:

> It just mentions one example where named faces are required, and I think
> the reader will take from that that Emacs will document when you can't
> use anonymous faces.  Since font locking doesn't say anything about
> that, then the natural interpretation is that font locking doesn't
> require named faces.

Please consider specifically the documentation of the function
font-lock-add-keywords that I used in the example. Its documentation
points to that of font-lock-keywords, which contains the description:

   FACENAME is an expression whose value is the face name to use.
   Instead of a face, FACENAME can evaluate to a property list of
   the form (face FACE PROP1 VAL1 PROP2 VAL2 ...)  in which case all
   the listed text-properties will be set rather than just FACE.

This currently states that a face name is expected.

Since the Elisp documentation also states: "Unless otherwise stated, we
will use the term “face” to refer only to named faces.", the notion of
"face" in the description above also does not include anonymous faces.

Would it work to mention that "face FACE" can also be omitted, i.e.,
that an anonymous face can also be specified here?

Thank you and all the best,
Markus