Re: A few questions about c++-ts-mode.

[Eli Zaretskii]

> From: Yuan Fu <casouri@gmail.com>
> Date: Tue, 7 May 2024 17:19:53 -0700
> Cc: emacs-devel@gnu.org
> 
> > 1. namespaces are not fontified like in c-mode (i.e in std::string the
> >  `std` used to have font-lock-constant-face while `string` used to have
> >  font-lock-type-face). It seems like tresitter identifies properly them
> >  like (namespace_identifier) and (type_identifier)
> 
> Then we probably want to fontify namespaces in constant face. Or perhaps add 
> a namespace-face that inherits from constant face.

I think using font-lock-constant-face is fine.  Patches welcome.

> > 2. Doc string comments are fontified like normal comments. It looks like
> >  treesiter does not recognize them at all. Is this something we need to
> >  report to treesitter or we need to workaround it in emacs side?
> 
> I’m working on that. I think the best way is to workaround it in Emacs.

Please note that some of those specially-formatted comments are
explicitly supported by the grammar.

> > 3. macros like `#if defined(something)` fontifies the whole macro with
> >  same font (the `identifier` used to have no colors in c++-mode)
> 
> We should update the fontification to leave out the identifier.

We seem to have the technology already, but we are overwriting it?
Observe:

     (preproc_defined) @font-lock-preprocessor-face
     (preproc_defined (identifier) @font-lock-variable-name-face)
     [,@c-ts-mode--preproc-keywords] @font-lock-preprocessor-face)