Subject: bug#34712: closed (Re: Fontification of simple macros)

From: [email-masked] (GNU bug Tracking System)
Date: Mon, 04 Mar 2019 20:19:02 +0000

Your bug report

#34712: Fontification of simple macros

which was filed against the auctex package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
34712: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=34712
GNU Bug Tracking System
Contact [email-masked] with problems

Subject: Re: Fontification of simple macros
From: Arash Esbati <[email-masked]>
To: [email-masked]
Date: Mon, 04 Mar 2019 21:17:51 +0100
List-Id: <debbugs-submit.debbugs.gnu.org>

Arash Esbati <[email-masked]> writes:

> A possible fix is attached below: We introduce a new variable
> `font-latex-match-simple-include-list' for styles to add their special
> characters for fontification to `font-latex-match-simple-command'
> which is modified as shown below:

Following up myself, I've pushed a slightly modified solution to AUCTeX
repo.  This should be fixed now.

Best, Arash

Subject: Fontification of simple macros
From: Arash Esbati <[email-masked]>
To: auctex-bugs <[email-masked]>
Date: Sat, 02 Mar 2019 21:53:15 +0100
List-Id: <debbugs-submit.debbugs.gnu.org>

Hi all,

while looking at this message[1], it seems that there is a bug in
font-latex.el.  This code

    \documentclass{beamer}

    \begin{document}

    \begin{frame}
      \frametitle<presentation>{MySlide}
                 |            |
             font-latex-sedate-face
    \end{frame}

    \foo<bar>-19+*

    \end{document}

looks like this for me:

Have a look at <...> and \foo<bar>-19+*.  I think the issue is that the
regexp in `font-latex-match-simple-command' is too greedy.  A possible
fix is attached below: We introduce a new variable
`font-latex-match-simple-include-list' for styles to add their special
characters for fontification to `font-latex-match-simple-command' which
is modified as shown below:

    \documentclass{beamer}

    \begin{document}

    \begin{frame}
      \frametitle<presentation>{MySlide}
                 |            |
             font-latex-sedate-face
    \end{frame}

    \foo<bar>-19+*

    \begin{verbatim}
    (defvar font-latex-match-simple-include-list nil
      "List of characters allowed in a macro for fontification.
    Each character is a string.")
    (make-variable-buffer-local 'font-latex-match-simple-include-list)

    (defun font-latex-match-simple-command (limit)
      "Search for command like \\foo before LIMIT."
      ;; \s_ matches chars with symbol syntax, \sw chars with word syntax,
      ;; \s. chars with punctuation syntax.  We must exclude matches where
      ;; the first character after the \ is a reserved character and
      ;; should not be fontified (e.g. \, in foo\,bar or \- in foo\-bar).
      ;; These characters are stored in
      ;; `font-latex-match-simple-exclude-list'.  In docTeX mode, we
      ;; remove "_" from this list to get correct fontification for macros
      ;; like `\__module_foo:nnn'
      (let* ((search (lambda ()
                       (TeX-re-search-forward-unescaped
                        (concat
                         ;; Chars directly after backslash
                         "\\\\\\(\\s_\\|\\sw\\|\\s.\\)"
                         ;; Start group of the following chars
                         "\\(?:["
                         ;; a-zA-Z are always allowed:
                         "a-zA-Z"
                         ;; Allow `@' used often to redefine internals
                         "@"
                         ;; Check for additional characters added by AUCTeX styles
                         (when font-latex-match-simple-include-list
                           (mapconcat #'identity
                                      font-latex-match-simple-include-list
                                      ""))
                         ;; End group
                         "]\\)*")
                        limit t)))
             (pos (funcall search)))
        (while (and pos
                    (member (match-string 1)
                            (if (eq major-mode 'doctex-mode)
                                (remove "_" font-latex-match-simple-exclude-list)
                              font-latex-match-simple-exclude-list)))
          (setq pos (funcall search)))
        pos))

    (font-latex-update-font-lock)

    \end{verbatim}

    \end{document}

E.g., `expl3.el' must do:

    (setq font-latex-match-simple-include-list '("_" ":"))

Any comments welcome.

Best, Arash

Footnotes:
[1]  http://lists.gnu.org/archive/html/auctex/2019-02/msg00005.html