root/trunk/lisp/textmodes/tex-mode.el

;;; tex-mode.el --- TeX, LaTeX, and SliTeX mode commands -*- coding: utf-8 -*-

;; Copyright (C) 1985, 1986, 1989, 1992, 1994, 1995, 1996, 1997, 1998, 1999,
;;   2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.

;; Maintainer: FSF
;; Keywords: tex

;; Contributions over the years by William F. Schelter, Dick King,
;; Stephen Gildea, Michael Prange, Jacob Gore, and Edward M. Reingold.

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 3, or (at your option)
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.

;;; Commentary:

;;; Code:

;; Pacify the byte-compiler
(eval-when-compile
  (require 'compare-w)
  (require 'cl)
  (require 'skeleton))

(defvar font-lock-comment-face)
(defvar font-lock-doc-face)

(require 'shell)
(require 'compile)

(defgroup tex-file nil
  "TeX files and directories."
  :prefix "tex-"
  :group 'tex)

(defgroup tex-run nil
  "Running external commands from TeX mode."
  :prefix "tex-"
  :group 'tex)

(defgroup tex-view nil
  "Viewing and printing TeX files."
  :prefix "tex-"
  :group 'tex)

;;;###autoload
(defcustom tex-shell-file-name nil
  "*If non-nil, the shell file name to run in the subshell used to run TeX."
  :type '(choice (const :tag "None" nil)
                 string)
  :group 'tex-run)

;;;###autoload
(defcustom tex-directory "."
  "*Directory in which temporary files are written.
You can make this `/tmp' if your TEXINPUTS has no relative directories in it
and you don't try to apply \\[tex-region] or \\[tex-buffer] when there are
`\\input' commands with relative directories."
  :type 'directory
  :group 'tex-file)

;;;###autoload
(defcustom tex-first-line-header-regexp nil
  "Regexp for matching a first line which `tex-region' should include.
If this is non-nil, it should be a regular expression string;
if it matches the first line of the file,
`tex-region' always includes the first line in the TeX run."
  :type '(choice (const :tag "None" nil)
                 regexp)
  :group 'tex-file)

;;;###autoload
(defcustom tex-main-file nil
  "*The main TeX source file which includes this buffer's file.
The command `tex-file' runs TeX on the file specified by `tex-main-file'
if the variable is non-nil."
  :type '(choice (const :tag "None" nil)
                 file)
  :group 'tex-file)

;;;###autoload
(defcustom tex-offer-save t
  "*If non-nil, ask about saving modified buffers before \\[tex-file] is run."
  :type 'boolean
  :group 'tex-file)

;;;###autoload
(defcustom tex-run-command "tex"
  "*Command used to run TeX subjob.
TeX Mode sets `tex-command' to this string.
See the documentation of that variable."
  :type 'string
  :group 'tex-run)

;;;###autoload
(defcustom latex-run-command "latex"
  "*Command used to run LaTeX subjob.
LaTeX Mode sets `tex-command' to this string.
See the documentation of that variable."
  :type 'string
  :group 'tex-run)

;;;###autoload
(defcustom slitex-run-command "slitex"
  "*Command used to run SliTeX subjob.
SliTeX Mode sets `tex-command' to this string.
See the documentation of that variable."
  :type 'string
  :group 'tex-run)

;;;###autoload
(defcustom tex-start-options ""
  "*TeX options to use when starting TeX.
These immediately precede the commands in `tex-start-commands'
and the input file name, with no separating space and are not shell-quoted.
If nil, TeX runs with no options.  See the documentation of `tex-command'."
  :type 'string
  :group 'tex-run
  :version "22.1")

;;;###autoload
(defcustom tex-start-commands "\\nonstopmode\\input"
  "*TeX commands to use when starting TeX.
They are shell-quoted and precede the input file name, with a separating space.
If nil, no commands are used.  See the documentation of `tex-command'."
  :type '(radio (const :tag "Interactive \(nil\)" nil)
                (const :tag "Nonstop \(\"\\nonstopmode\\input\"\)"
                       "\\nonstopmode\\input")
                (string :tag "String at your choice"))
  :group 'tex-run
  :version "22.1")

(defvar latex-standard-block-names
  '("abstract"          "array"         "center"        "description"
    "displaymath"       "document"      "enumerate"     "eqnarray"
    "eqnarray*"         "equation"      "figure"        "figure*"
    "flushleft"         "flushright"    "itemize"       "letter"
    "list"              "minipage"      "picture"       "quotation"
    "quote"             "slide"         "sloppypar"     "tabbing"
    "table"             "table*"        "tabular"       "tabular*"
    "thebibliography"   "theindex*"     "titlepage"     "trivlist"
    "verbatim"          "verbatim*"     "verse"         "math")
  "Standard LaTeX block names.")

;;;###autoload
(defcustom latex-block-names nil
  "*User defined LaTeX block names.
Combined with `latex-standard-block-names' for minibuffer completion."
  :type '(repeat string)
  :group 'tex-run)

;;;###autoload
(defcustom tex-bibtex-command "bibtex"
  "*Command used by `tex-bibtex-file' to gather bibliographic data.
If this string contains an asterisk (`*'), that is replaced by the file name;
otherwise, the file name, preceded by blank, is added at the end."
  :type 'string
  :group 'tex-run)

;;;###autoload
(defcustom tex-dvi-print-command "lpr -d"
  "*Command used by \\[tex-print] to print a .dvi file.
If this string contains an asterisk (`*'), that is replaced by the file name;
otherwise, the file name, preceded by blank, is added at the end."
  :type 'string
  :group 'tex-view)

;;;###autoload
(defcustom tex-alt-dvi-print-command "lpr -d"
  "*Command used by \\[tex-print] with a prefix arg to print a .dvi file.
If this string contains an asterisk (`*'), that is replaced by the file name;
otherwise, the file name, preceded by blank, is added at the end.

If two printers are not enough of a choice, you can set the variable
`tex-alt-dvi-print-command' to an expression that asks what you want;
for example,

    (setq tex-alt-dvi-print-command
         '(format \"lpr -P%s\" (read-string \"Use printer: \")))

would tell \\[tex-print] with a prefix argument to ask you which printer to
use."
  :type '(choice (string :tag "Command")
                 (sexp :tag "Expression"))
  :group 'tex-view)

;;;###autoload
(defcustom tex-dvi-view-command
  '(cond
    ((eq window-system 'x) "xdvi")
    ((eq window-system 'w32) "yap")
    (t "dvi2tty * | cat -s"))
  "*Command used by \\[tex-view] to display a `.dvi' file.
If it is a string, that specifies the command directly.
If this string contains an asterisk (`*'), that is replaced by the file name;
otherwise, the file name, preceded by a space, is added at the end.

If the value is a form, it is evaluated to get the command to use."
  :type '(choice (const nil) string sexp)
  :group 'tex-view)

;;;###autoload
(defcustom tex-show-queue-command "lpq"
  "*Command used by \\[tex-show-print-queue] to show the print queue.
Should show the queue(s) that \\[tex-print] puts jobs on."
  :type 'string
  :group 'tex-view)

;;;###autoload
(defcustom tex-default-mode 'latex-mode
  "*Mode to enter for a new file that might be either TeX or LaTeX.
This variable is used when it can't be determined whether the file
is plain TeX or LaTeX or what because the file contains no commands.
Normally set to either `plain-tex-mode' or `latex-mode'."
  :type 'function
  :group 'tex)

;;;###autoload
(defcustom tex-open-quote "``"
  "*String inserted by typing \\[tex-insert-quote] to open a quotation."
  :type 'string
  :options '("``" "\"<" "\"`" "<<" "«")
  :group 'tex)

;;;###autoload
(defcustom tex-close-quote "''"
  "*String inserted by typing \\[tex-insert-quote] to close a quotation."
  :type 'string
  :options '("''" "\">" "\"'" ">>" "»")
  :group 'tex)

(defvar tex-last-temp-file nil
  "Latest temporary file generated by \\[tex-region] and \\[tex-buffer].
Deleted when the \\[tex-region] or \\[tex-buffer] is next run, or when the
tex shell terminates.")

(defvar tex-command "tex"
  "*Command to run TeX.
If this string contains an asterisk \(`*'\), that is replaced by the file name;
otherwise the value of `tex-start-options', the \(shell-quoted\)
value of `tex-start-commands', and the file name are added at the end
with blanks as separators.

In TeX, LaTeX, and SliTeX Mode this variable becomes buffer local.
In these modes, use \\[set-variable] if you want to change it for the
current buffer.")

(defvar tex-trailer nil
  "String appended after the end of a region sent to TeX by \\[tex-region].")

(defvar tex-start-of-header nil
  "Regular expression used by \\[tex-region] to find start of file's header.")

(defvar tex-end-of-header nil
  "Regular expression used by \\[tex-region] to find end of file's header.")

(defvar tex-shell-cd-command "cd"
  "Command to give to shell running TeX to change directory.
The value of `tex-directory' is appended to this, separated by a space.")

(defvar tex-zap-file nil
  "Temporary file name used for text being sent as input to TeX.
Should be a simple file name with no extension or directory specification.")

(defvar tex-last-buffer-texed nil
  "Buffer which was last TeXed.")

(defvar tex-print-file nil
  "File name that \\[tex-print] prints.
Set by \\[tex-region], \\[tex-buffer], and \\[tex-file].")

(defvar tex-mode-syntax-table
  (let ((st (make-syntax-table)))
    (modify-syntax-entry ?% "<" st)
    (modify-syntax-entry ?\n ">" st)
    (modify-syntax-entry ?\f ">" st)
    (modify-syntax-entry ?\C-@ "w" st)
    (modify-syntax-entry ?' "w" st)
    (modify-syntax-entry ?@ "_" st)
    (modify-syntax-entry ?* "_" st)
    (modify-syntax-entry ?\t " " st)
    ;; ~ is printed by TeX as a space, but it's semantics in the syntax
    ;; of TeX is not `whitespace' (i.e. it's just like \hspace{foo}).
    (modify-syntax-entry ?~ "." st)
    (modify-syntax-entry ?$ "$$" st)
    (modify-syntax-entry ?\\ "/" st)
    (modify-syntax-entry ?\" "." st)
    (modify-syntax-entry ?& "." st)
    (modify-syntax-entry ?_ "." st)
    (modify-syntax-entry ?^ "." st)
    st)
  "Syntax table used while in TeX mode.")

;;;;
;;;; Imenu support
;;;;

(defcustom latex-imenu-indent-string ". "
  "*String to add repeated in front of nested sectional units for Imenu.
An alternative value is \" . \", if you use a font with a narrow period."
  :type 'string
  :group 'tex)

(defvar latex-section-alist
  '(("part" . 0) ("chapter" . 1)
    ("section" . 2) ("subsection" . 3)
    ("subsubsection" . 4)
    ("paragraph" . 5) ("subparagraph" . 6)))

(defvar latex-metasection-list
  '("documentstyle" "documentclass"
    "begin{document}" "end{document}"
    "appendix" "frontmatter" "mainmatter" "backmatter"))

(defun latex-imenu-create-index ()
  "Generate an alist for imenu from a LaTeX buffer."
  (let ((section-regexp
         (concat "\\\\" (regexp-opt (mapcar 'car latex-section-alist) t)
                 "\\*?[ \t]*{"))
        (metasection-regexp
         (concat "\\\\" (regexp-opt latex-metasection-list t)))
        i0 menu case-fold-search)
    (save-excursion
      ;; Find the top-most level in this file but don't allow it to be
      ;; any deeper than "section" (which is top-level in an article).
      (goto-char (point-min))
      (if (search-forward-regexp "\\\\part\\*?[ \t]*{" nil t)
          (setq i0 0)
        (if (search-forward-regexp "\\\\chapter\\*?[ \t]*{" nil t)
            (setq i0 1)
          (setq i0 2)))

      ;; Look for chapters and sections.
      (goto-char (point-min))
      (while (search-forward-regexp section-regexp nil t)
        (let ((start (match-beginning 0))
              (here (point))
              (i (cdr (assoc (buffer-substring-no-properties
                              (match-beginning 1)
                              (match-end 1))
                             latex-section-alist))))
          (backward-char 1)
          (condition-case err
              (progn
                ;; Using sexps allows some use of matching {...} inside
                ;; titles.
                (forward-sexp 1)
                (push (cons (concat (apply 'concat
                                           (make-list
                                            (max 0 (- i i0))
                                            latex-imenu-indent-string))
                                    (buffer-substring-no-properties
                                     here (1- (point))))
                            start)
                      menu))
            (error nil))))

      ;; Look for included material.
      (goto-char (point-min))
      (while (search-forward-regexp
              "\\\\\\(include\\|input\\|verbatiminput\\|bibliography\\)\
\[ \t]*{\\([^}\n]+\\)}"
              nil t)
        (push (cons (concat "<<" (buffer-substring-no-properties
                                  (match-beginning 2)
                                  (match-end 2))
                            (if (= (char-after (match-beginning 1)) ?b)
                                ".bbl"
                              ".tex"))
                    (match-beginning 0))
              menu))

      ;; Look for \frontmatter, \mainmatter, \backmatter, and \appendix.
      (goto-char (point-min))
      (while (search-forward-regexp metasection-regexp nil t)
        (push (cons "--" (match-beginning 0)) menu))

      ;; Sort in increasing buffer position order.
      (sort menu (function (lambda (a b) (< (cdr a) (cdr b))))))))

;;;;
;;;; Outline support
;;;;

(defvar latex-outline-regexp
  (concat "\\\\"
          (regexp-opt (append latex-metasection-list
                              (mapcar 'car latex-section-alist)) t)))

(defun latex-outline-level ()
  (if (looking-at latex-outline-regexp)
      (1+ (or (cdr (assoc (match-string 1) latex-section-alist)) -1))
    1000))

;;;;
;;;; Font-Lock support
;;;;

;(defvar tex-font-lock-keywords
;  ;; Regexps updated with help from Ulrik Dickow <dickow@nbi.dk>.
;  '(("\\\\\\(begin\\|end\\|newcommand\\){\\([a-zA-Z0-9\\*]+\\)}"
;     2 font-lock-function-name-face)
;    ("\\\\\\(cite\\|label\\|pageref\\|ref\\){\\([^} \t\n]+\\)}"
;     2 font-lock-constant-face)
;    ;; It seems a bit dubious to use `bold' and `italic' faces since we might
;    ;; not be able to display those fonts.
;    ("{\\\\bf\\([^}]+\\)}" 1 'bold keep)
;    ("{\\\\\\(em\\|it\\|sl\\)\\([^}]+\\)}" 2 'italic keep)
;    ("\\\\\\([a-zA-Z@]+\\|.\\)" . font-lock-keyword-face)
;    ("^[ \t\n]*\\\\def[\\\\@]\\(\\w+\\)" 1 font-lock-function-name-face keep))
;  ;; Rewritten and extended for LaTeX2e by Ulrik Dickow <dickow@nbi.dk>.
;  '(("\\\\\\(begin\\|end\\|newcommand\\){\\([a-zA-Z0-9\\*]+\\)}"
;     2 font-lock-function-name-face)
;    ("\\\\\\(cite\\|label\\|pageref\\|ref\\){\\([^} \t\n]+\\)}"
;     2 font-lock-constant-face)
;    ("^[ \t]*\\\\def\\\\\\(\\(\\w\\|@\\)+\\)" 1 font-lock-function-name-face)
;    "\\\\\\([a-zA-Z@]+\\|.\\)"
;    ;; It seems a bit dubious to use `bold' and `italic' faces since we might
;    ;; not be able to display those fonts.
;    ;; LaTeX2e: \emph{This is emphasized}.
;    ("\\\\emph{\\([^}]+\\)}" 1 'italic keep)
;    ;; LaTeX2e: \textbf{This is bold}, \textit{...}, \textsl{...}
;    ("\\\\text\\(\\(bf\\)\\|it\\|sl\\){\\([^}]+\\)}"
;     3 (if (match-beginning 2) 'bold 'italic) keep)
;    ;; Old-style bf/em/it/sl.  Stop at `\\' and un-escaped `&', for tables.
;    ("\\\\\\(\\(bf\\)\\|em\\|it\\|sl\\)\\>\\(\\([^}&\\]\\|\\\\[^\\]\\)+\\)"
;     3 (if (match-beginning 2) 'bold 'italic) keep))

;; Rewritten with the help of Alexandra Bac <abac@welcome.disi.unige.it>.
(defconst tex-font-lock-keywords-1
  (eval-when-compile
    (let* (;; Names of commands whose arg should be fontified as heading, etc.
           (headings (regexp-opt
                      '("title"  "begin" "end" "chapter" "part"
                        "section" "subsection" "subsubsection"
                        "paragraph" "subparagraph" "subsubparagraph"
                        "newcommand" "renewcommand" "providecommand"
                        "newenvironment" "renewenvironment"
                        "newtheorem" "renewtheorem")
                      t))
           (variables (regexp-opt
                       '("newcounter" "newcounter*" "setcounter" "addtocounter"
                         "setlength" "addtolength" "settowidth")
                       t))
           (includes (regexp-opt
                      '("input" "include" "includeonly" "bibliography"
                        "epsfig" "psfig" "epsf" "nofiles" "usepackage"
                        "documentstyle" "documentclass" "verbatiminput"
                        "includegraphics" "includegraphics*"
                        "url" "nolinkurl")
                      t))
           ;; Miscellany.
           (slash "\\\\")
           (opt " *\\(\\[[^]]*\\] *\\)*")
           ;; This would allow highlighting \newcommand\CMD but requires
           ;; adapting subgroup numbers below.
           ;; (arg "\\(?:{\\(\\(?:[^{}\\]+\\|\\\\.\\|{[^}]*}\\)+\\)\\|\\\\[a-z*]+\\)"))
           (arg "{\\(\\(?:[^{}\\]+\\|\\\\.\\|{[^}]*}\\)+\\)"))
      (list
       ;; font-lock-syntactic-keywords causes the \ of \end{verbatim} to be
       ;; highlighted as tex-verbatim face.  Let's undo that.
       ;; This is ugly and brittle :-(  --Stef
       '("^\\(\\\\\\)end" (1 (get-text-property (match-end 1) 'face) t))
       ;; display $$ math $$
       ;; We only mark the match between $$ and $$ because the $$ delimiters
       ;; themselves have already been marked (along with $..$) by syntactic
       ;; fontification.  Also this is done at the very beginning so as to
       ;; interact with the other keywords in the same way as $...$ does.
       (list "\\$\\$\\([^$]+\\)\\$\\$" 1 'tex-math-face)
       ;; Heading args.
       (list (concat slash headings "\\*?" opt arg)
             ;; If ARG ends up matching too much (if the {} don't match, f.ex)
             ;; jit-lock will do funny things: when updating the buffer
             ;; the re-highlighting is only done locally so it will just
             ;; match the local line, but defer-contextually will
             ;; match more lines at a time, so ARG will end up matching
             ;; a lot more, which might suddenly include a comment
             ;; so you get things highlighted bold when you type them
             ;; but they get turned back to normal a little while later
             ;; because "there's already a face there".
             ;; Using `keep' works around this un-intuitive behavior as well
             ;; as improves the behavior in the very rare case where you do
             ;; have a comment in ARG.
             3 'font-lock-function-name-face 'keep)
       (list (concat slash "\\(?:provide\\|\\(?:re\\)?new\\)command\\** *\\(\\\\[A-Za-z@]+\\)")
             1 'font-lock-function-name-face 'keep)
       ;; Variable args.
       (list (concat slash variables " *" arg) 2 'font-lock-variable-name-face)
       ;; Include args.
       (list (concat slash includes opt arg) 3 'font-lock-builtin-face)
       ;; Definitions.  I think.
       '("^[ \t]*\\\\def *\\\\\\(\\(\\w\\|@\\)+\\)"
         1 font-lock-function-name-face))))
  "Subdued expressions to highlight in TeX modes.")

(defun tex-font-lock-append-prop (prop)
  (unless (memq (get-text-property (match-end 1) 'face)
                '(font-lock-comment-face tex-verbatim))
    prop))

(defconst tex-font-lock-keywords-2
  (append tex-font-lock-keywords-1
   (eval-when-compile
     (let* (;;
            ;; Names of commands whose arg should be fontified with fonts.
            (bold (regexp-opt '("textbf" "textsc" "textup"
                                "boldsymbol" "pmb") t))
            (italic (regexp-opt '("textit" "textsl" "emph") t))
            ;; FIXME: unimplemented yet.
            ;; (type (regexp-opt '("texttt" "textmd" "textrm" "textsf") t))
            ;;
            ;; Names of commands whose arg should be fontified as a citation.
            (citations (regexp-opt
                        '("label" "ref" "pageref" "vref" "eqref"
                          "cite" "nocite" "index" "glossary" "bibitem"
                          ;; These are text, rather than citations.
                          ;; "caption" "footnote" "footnotemark" "footnotetext"
                          )
                        t))
            ;;
            ;; Names of commands that should be fontified.
            (specials-1 (regexp-opt '("\\" "\\*") t)) ;; "-"
            (specials-2 (regexp-opt
                         '("linebreak" "nolinebreak" "pagebreak" "nopagebreak"
                           "newline" "newpage" "clearpage" "cleardoublepage"
                           "displaybreak" "allowdisplaybreaks"
                           "enlargethispage") t))
            (general "\\([a-zA-Z@]+\\**\\|[^ \t\n]\\)")
            ;;
            ;; Miscellany.
            (slash "\\\\")
            (opt " *\\(\\[[^]]*\\] *\\)*")
            (args "\\(\\(?:[^{}&\\]+\\|\\\\.\\|{[^}]*}\\)+\\)")
            (arg "{\\(\\(?:[^{}\\]+\\|\\\\.\\|{[^}]*}\\)+\\)"))
       (list
        ;;
        ;; Citation args.
        (list (concat slash citations opt arg) 3 'font-lock-constant-face)
        ;;
        ;; Text between `` quotes ''.
        (cons (concat (regexp-opt `("``" "\"<" "\"`" "<<" "«") t)
                      "[^'\">{]+"       ;a bit pessimistic
                      (regexp-opt `("''" "\">" "\"'" ">>" "»") t))
              'font-lock-string-face)
        ;;
        ;; Command names, special and general.
        (cons (concat slash specials-1) 'font-lock-warning-face)
        (list (concat "\\(" slash specials-2 "\\)\\([^a-zA-Z@]\\|\\'\\)")
              1 'font-lock-warning-face)
        (concat slash general)
        ;;
        ;; Font environments.  It seems a bit dubious to use `bold' etc. faces
        ;; since we might not be able to display those fonts.
        (list (concat slash bold " *" arg) 2
              '(tex-font-lock-append-prop 'bold) 'append)
        (list (concat slash italic " *" arg) 2
              '(tex-font-lock-append-prop 'italic) 'append)
        ;; (list (concat slash type arg) 2 '(quote bold-italic) 'append)
        ;;
        ;; Old-style bf/em/it/sl.  Stop at `\\' and un-escaped `&', for tables.
        (list (concat "\\\\\\(em\\|it\\|sl\\)\\>" args)
              2 '(tex-font-lock-append-prop 'italic) 'append)
        ;; This is separate from the previous one because of cases like
        ;; {\em foo {\bf bar} bla} where both match.
        (list (concat "\\\\\\(bf\\(series\\)?\\)\\>" args)
              3 '(tex-font-lock-append-prop 'bold) 'append)))))
   "Gaudy expressions to highlight in TeX modes.")

(defun tex-font-lock-suscript (pos)
  (unless (or (memq (get-text-property pos 'face)
                    '(font-lock-constant-face font-lock-builtin-face
                      font-lock-comment-face tex-verbatim))
              ;; Check for backslash quoting
              (let ((odd nil)
                    (pos pos))
                (while (eq (char-before pos) ?\\)
                  (setq pos (1- pos) odd (not odd)))
                odd))
    (if (eq (char-after pos) ?_)
        '(face subscript display (raise -0.3))
      '(face superscript display (raise +0.3)))))

(defun tex-font-lock-match-suscript (limit)
  "Match subscript and superscript patterns up to LIMIT."
  (when (re-search-forward "[_^] *\\([^\n\\{}]\\|\
\\\\\\([a-zA-Z@]+\\|[^ \t\n]\\)\\|\\({\\)\\)" limit t)
    (when (match-end 3)
      (let ((beg (match-beginning 3))
            (end (save-restriction
                   (narrow-to-region (point-min) limit)
                   (condition-case nil (scan-lists (point) 1 1) (error nil)))))
        (store-match-data (if end
                              (list (match-beginning 0) end beg end)
                            (list beg beg beg beg)))))
    t))

(defconst tex-font-lock-keywords-3
  (append tex-font-lock-keywords-2
          '((tex-font-lock-match-suscript
             (1 (tex-font-lock-suscript (match-beginning 0)) append))))
  "Experimental expressions to highlight in TeX modes.")

(defvar tex-font-lock-keywords tex-font-lock-keywords-1
  "Default expressions to highlight in TeX modes.")

(defvar tex-verbatim-environments
  '("verbatim" "verbatim*"))

(defvar tex-font-lock-syntactic-keywords
  (let ((verbs (regexp-opt tex-verbatim-environments t)))
    `((,(concat "^\\\\begin *{" verbs "}.*\\(\n\\)") 2 "|")
      ;; Technically, we'd like to put the "|" property on the \n preceding
      ;; the \end, but this would have 2 disadvantages:
      ;; 1 - it's wrong if the verbatim env is empty (the same \n is used to
      ;;     start and end the fenced-string).
      ;; 2 - font-lock considers the preceding \n as being part of the
      ;;     preceding line, so things gets screwed every time the previous
      ;;     line is re-font-locked on its own.
      ;; There's a hack in tex-font-lock-keywords-1 to remove the verbatim
      ;; face from the \ but C-M-f still jumps to the wrong spot :-(  --Stef
      (,(concat "^\\(\\\\\\)end *{" verbs "}\\(.?\\)") (1 "|") (3 "<"))
      ;; ("^\\(\\\\\\)begin *{comment}" 1 "< b")
      ;; ("^\\\\end *{comment}.*\\(\n\\)" 1 "> b")
      ("\\\\verb\\**\\([^a-z@*]\\)"
       ;; Do it last, because it uses syntax-ppss which needs the
       ;; syntax-table properties of previous entries.
       1 (tex-font-lock-verb (match-end 1))))))

(defun tex-font-lock-unfontify-region (beg end)
  (font-lock-default-unfontify-region beg end)
  (while (< beg end)
    (let ((next (next-single-property-change beg 'display nil end))
          (prop (get-text-property beg 'display)))
      (if (and (eq (car-safe prop) 'raise)
               (member (car-safe (cdr prop)) '(-0.3 +0.3))
               (null (cddr prop)))
          (put-text-property beg next 'display nil))
      (setq beg next))))

(defface superscript
  '((t :height 0.8)) ;; :raise 0.3
  "Face used for superscripts."
  :group 'tex)
(defface subscript
  '((t :height 0.8)) ;; :raise -0.3
  "Face used for subscripts."
  :group 'tex)

(defface tex-math
  '((t :inherit font-lock-string-face))
  "Face used to highlight TeX math expressions."
  :group 'tex)
;; backward-compatibility alias
(put 'tex-math-face 'face-alias 'tex-math)
(defvar tex-math-face 'tex-math)

(defface tex-verbatim
  ;; '((t :inherit font-lock-string-face))
  '((t :family "courier"))
  "Face used to highlight TeX verbatim environments."
  :group 'tex)
;; backward-compatibility alias
(put 'tex-verbatim-face 'face-alias 'tex-verbatim)
(defvar tex-verbatim-face 'tex-verbatim)

(defun tex-font-lock-verb (end)
  "Place syntax-table properties on the \verb construct.
END is the position of the first delimiter after \verb."
  (unless (nth 8 (syntax-ppss end))
    ;; Do nothing if the \verb construct is itself inside a comment or
    ;; verbatim env.
    (save-excursion
      ;; Let's find the end and mark it.
      ;; We used to do it inside tex-font-lock-syntactic-face-function, but
      ;; this leads to funny effects when jumping to the end of the buffer,
      ;; because font-lock applies font-lock-syntactic-keywords to the whole
      ;; preceding text but font-lock-syntactic-face-function only to the
      ;; actually displayed text.
      (goto-char end)
      (let ((char (char-before)))
        (skip-chars-forward (string ?^ char)) ;; Use `end' ?
        (when (eq (char-syntax (preceding-char)) ?/)
          (put-text-property (1- (point)) (point) 'syntax-table '(1)))
        (unless (eobp)
          (put-text-property (point) (1+ (point)) 'syntax-table '(7))
          ;; Cause the rest of the buffer to be re-fontified.
          ;; (remove-text-properties (1+ (point)) (point-max) '(fontified))
          )))
    "\""))

;; Use string syntax but math face for $...$.
(defun tex-font-lock-syntactic-face-function (state)
  (let ((char (nth 3 state)))
    (cond
     ((not char) font-lock-comment-face)
     ((eq char ?$) tex-math-face)
     (t tex-verbatim-face))))


(defun tex-define-common-keys (keymap)
  "Define the keys that we want defined both in TeX mode and in the TeX shell."
  (define-key keymap "\C-c\C-k" 'tex-kill-job)
  (define-key keymap "\C-c\C-l" 'tex-recenter-output-buffer)
  (define-key keymap "\C-c\C-q" 'tex-show-print-queue)
  (define-key keymap "\C-c\C-p" 'tex-print)
  (define-key keymap "\C-c\C-v" 'tex-view)

  (define-key keymap [menu-bar tex] (cons "TeX" (make-sparse-keymap "TeX")))

  (define-key keymap [menu-bar tex tex-kill-job]
    '(menu-item "Tex Kill" tex-kill-job :enable (tex-shell-running)))
  (define-key keymap [menu-bar tex tex-recenter-output-buffer]
    '(menu-item "Tex Recenter" tex-recenter-output-buffer
                :enable (get-buffer "*tex-shell*")))
  (define-key keymap [menu-bar tex tex-show-print-queue]
    '("Show Print Queue" . tex-show-print-queue))
  (define-key keymap [menu-bar tex tex-alt-print]
    '(menu-item "Tex Print (alt printer)" tex-alt-print
                :enable (stringp tex-print-file)))
  (define-key keymap [menu-bar tex tex-print]
    '(menu-item "Tex Print" tex-print :enable (stringp tex-print-file)))
  (define-key keymap [menu-bar tex tex-view]
    '(menu-item "Tex View" tex-view :enable (stringp tex-print-file))))

(defvar tex-mode-map
  (let ((map (make-sparse-keymap)))
    (set-keymap-parent map text-mode-map)
    (tex-define-common-keys map)
    (define-key map