code.delx.au - gnu-emacs/blob - lisp/textmodes/nroff-mode.el

   1 ;;; nroff-mode.el --- GNU Emacs major mode for editing nroff source
   2
   3 ;; Copyright (C) 1985, 1986, 1994, 1995, 1997, 2001, 2002, 2003,
   4 ;;   2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
   5
   6 ;; Maintainer: FSF
   7 ;; Keywords: wp
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software: you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation, either version 3 of the License, or
  14 ;; (at your option) any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;; This package is a major mode for editing nroff source code.  It knows
  27 ;; about various nroff constructs, ms, mm, and me macros, and will fill
  28 ;; and indent paragraphs properly in their presence.  It also includes
  29 ;; a command to count text lines (excluding nroff constructs), a command
  30 ;; to center a line, and movement commands that know how to skip macros.
  31
  32 ;; Paragraph filling and line-counting currently don't respect comments,
  33 ;; as they should.
  34
  35 ;;; Code:
  36
  37 (defgroup nroff nil
  38   "Nroff mode."
  39   :link '(custom-group-link :tag "Font Lock Faces group" font-lock-faces)
  40   :group 'wp
  41   :prefix "nroff-")
  42
  43
  44 (defcustom nroff-electric-mode nil
  45   "Non-nil means automatically closing requests when you insert an open."
  46   :group 'nroff
  47   :type 'boolean)
  48
  49 (defvar nroff-mode-map
  50   (let ((map (make-sparse-keymap))
  51         (menu-map (make-sparse-keymap)))
  52     (define-key map "\t"  'tab-to-tab-stop)
  53     (define-key map "\es" 'center-line)
  54     (define-key map "\e?" 'nroff-count-text-lines)
  55     (define-key map "\n"  'nroff-electric-newline)
  56     (define-key map "\en" 'nroff-forward-text-line)
  57     (define-key map "\ep" 'nroff-backward-text-line)
  58     (define-key map "\C-c\C-c" 'nroff-view)
  59     (define-key map [menu-bar nroff-mode] (cons "Nroff" menu-map))
  60     (define-key menu-map [nn]
  61       '(menu-item "Newline" nroff-electric-newline
  62                   :help "Insert newline for nroff mode; special if nroff-electric mode"))
  63     (define-key menu-map [nc]
  64       '(menu-item "Count text lines" nroff-count-text-lines
  65                   :help "Count lines in region, except for nroff request lines."))
  66     (define-key menu-map [nf]
  67       '(menu-item "Forward text line" nroff-forward-text-line
  68                   :help "Go forward one nroff text line, skipping lines of nroff requests"))
  69     (define-key menu-map [nb]
  70       '(menu-item "Backward text line" nroff-backward-text-line
  71                   :help "Go backward one nroff text line, skipping lines of nroff requests"))
  72     (define-key menu-map [ne]
  73       '(menu-item "Electric newline mode"
  74                   nroff-electric-mode
  75                   :help "Auto insert closing requests if necessary"
  76                   :button (:toggle . nroff-electric-mode)))
  77     (define-key menu-map [npm]
  78       '(menu-item "Preview as man page" nroff-view
  79                   :help "Run man on this file."))
  80     map)
  81   "Major mode keymap for `nroff-mode'.")
  82
  83 (defvar nroff-mode-syntax-table
  84   (let ((st (copy-syntax-table text-mode-syntax-table)))
  85     ;; " isn't given string quote syntax in text-mode but it
  86     ;; (arguably) should be for use round nroff arguments (with ` and
  87     ;; ' used otherwise).
  88     (modify-syntax-entry ?\" "\"  2" st)
  89     ;; Comments are delimited by \" and newline.
  90     ;; And in groff also \# to newline.
  91     (modify-syntax-entry ?# ".  2"  st)
  92     (modify-syntax-entry ?\\ "\\  1" st)
  93     (modify-syntax-entry ?\n ">" st)
  94     st)
  95   "Syntax table used while in `nroff-mode'.")
  96
  97 (defvar nroff-imenu-expression
  98   ;; man headers:
  99   '((nil "^\\.SH \"?\\([^\"\n]*\\)\"?$" 1)))
 100
 101 (defcustom nroff-font-lock-keywords
 102   (list
 103    ;; Directives are . or ' at start of line, followed by
 104    ;; optional whitespace, then command (which my be longer than
 105    ;; 2 characters in groff).  Perhaps the arguments should be
 106    ;; fontified as well.
 107    "^[.']\\s-*\\sw+"
 108    ;; There are numerous groff escapes; the following get things
 109    ;; like \-, \(em (standard troff) and \f[bar] (groff
 110    ;; variants).  This won't currently do groff's \A'foo' and
 111    ;; the like properly.  One might expect it to highlight an escape's
 112    ;; arguments in common cases, like \f.
 113    (concat "\\\\"                     ; backslash
 114          "\\("                        ; followed by various possibilities
 115          (mapconcat 'identity
 116                     '("[f*n]*\\[.+?]" ; some groff extensions
 117                       "(.."           ; two chars after (
 118                       "[^(\"#]"       ; single char escape
 119                       ) "\\|")
 120          "\\)")
 121    )
 122   "Font-lock highlighting control in `nroff-mode'."
 123   :group 'nroff
 124   :type '(repeat regexp))
 125
 126 (defcustom nroff-mode-hook nil
 127   "Hook run by function `nroff-mode'."
 128   :type 'hook
 129   :group 'nroff)
 130
 131 ;;;###autoload
 132 (define-derived-mode nroff-mode text-mode "Nroff"
 133   "Major mode for editing text intended for nroff to format.
 134 \\{nroff-mode-map}
 135 Turning on Nroff mode runs `text-mode-hook', then `nroff-mode-hook'.
 136 Also, try `nroff-electric-mode', for automatically inserting
 137 closing requests for requests that are used in matched pairs."
 138   (set (make-local-variable 'font-lock-defaults)
 139        ;; SYNTAX-BEGIN is set to backward-paragraph to avoid slow-down
 140        ;; near the end of large buffers due to searching to buffer's
 141        ;; beginning.
 142        '(nroff-font-lock-keywords nil t nil backward-paragraph))
 143   (set (make-local-variable 'outline-regexp) "\\.H[ ]+[1-7]+ ")
 144   (set (make-local-variable 'outline-level) 'nroff-outline-level)
 145   ;; now define a bunch of variables for use by commands in this mode
 146   (set (make-local-variable 'page-delimiter) "^\\.\\(bp\\|SK\\|OP\\)")
 147   (set (make-local-variable 'paragraph-start)
 148        (concat "[.']\\|" paragraph-start))
 149   (set (make-local-variable 'paragraph-separate)
 150        (concat "[.']\\|" paragraph-separate))
 151   ;; Don't auto-fill directive lines starting . or ' since they normally
 152   ;; have to be one line.  But do auto-fill comments .\" .\# and '''.
 153   ;; Comment directives (those starting . or ') are [.'][ \t]*\\[#"]
 154   ;; or ''', and this regexp is everything except those.  So [.']
 155   ;; followed by not backslash and not ' or followed by backslash but
 156   ;; then not # or "
 157   (set (make-local-variable 'auto-fill-inhibit-regexp)
 158        "[.'][ \t]*\\([^ \t\\']\\|\\\\[^#\"]\\)")
 159   ;; comment syntax added by mit-erl!gildea 18 Apr 86
 160   (set (make-local-variable 'comment-start) "\\\" ")
 161   (set (make-local-variable 'comment-start-skip) "\\\\[\"#][ \t]*")
 162   (set (make-local-variable 'comment-column) 24)
 163   (set (make-local-variable 'comment-indent-function) 'nroff-comment-indent)
 164   (set (make-local-variable 'comment-insert-comment-function)
 165        'nroff-insert-comment-function)
 166   (set (make-local-variable 'imenu-generic-expression) nroff-imenu-expression))
 167
 168 (defun nroff-outline-level ()
 169   (save-excursion
 170     (looking-at outline-regexp)
 171     (skip-chars-forward ".H ")
 172     (string-to-number (buffer-substring (point) (+ 1 (point))))))
 173
 174 ;; Compute how much to indent a comment in nroff/troff source.
 175 ;; By mit-erl!gildea April 86
 176 (defun nroff-comment-indent ()
 177   "Compute indent for an nroff/troff comment.
 178 Puts a full-stop before comments on a line by themselves."
 179   (let ((pt (point)))
 180     (unwind-protect
 181         (progn
 182           (skip-chars-backward " \t")
 183           (if (bolp)
 184               (progn
 185                 ;; FIXME delete-horizontal-space?
 186                 (setq pt (1+ pt))
 187                 (insert ?.)
 188                 1)
 189             (if (save-excursion
 190                   (backward-char 1)
 191                   (looking-at "^[.']"))
 192                 1
 193               (max comment-column
 194                    (* 8 (/ (+ (current-column)
 195                               9) 8)))))) ; add 9 to ensure at least two blanks
 196       (goto-char pt))))
 197
 198 ;; http://lists.gnu.org/archive/html/emacs-devel/2007-10/msg01869.html
 199 (defun nroff-insert-comment-function ()
 200   "Function for `comment-insert-comment-function' in `nroff-mode'."
 201   (indent-to (nroff-comment-indent))
 202   (insert comment-start))
 203
 204 (defun nroff-count-text-lines (start end &optional print)
 205   "Count lines in region, except for nroff request lines.
 206 All lines not starting with a period are counted up.
 207 Interactively, print result in echo area.
 208 Noninteractively, return number of non-request lines from START to END."
 209   (interactive "r\np")
 210   (if print
 211       (message "Region has %d text lines" (nroff-count-text-lines start end))
 212     (save-excursion
 213       (save-restriction
 214         (narrow-to-region start end)
 215         (goto-char (point-min))
 216         (- (buffer-size) (nroff-forward-text-line (buffer-size)))))))
 217
 218 (defun nroff-forward-text-line (&optional cnt)
 219   "Go forward one nroff text line, skipping lines of nroff requests.
 220 An argument is a repeat count; if negative, move backward."
 221   (interactive "p")
 222   (if (not cnt) (setq cnt 1))
 223   (while (and (> cnt 0) (not (eobp)))
 224     (forward-line 1)
 225     (while (and (not (eobp)) (looking-at "[.']."))
 226       (forward-line 1))
 227     (setq cnt (- cnt 1)))
 228   (while (and (< cnt 0) (not (bobp)))
 229     (forward-line -1)
 230     (while (and (not (bobp))
 231                 (looking-at "[.']."))
 232       (forward-line -1))
 233     (setq cnt (+ cnt 1)))
 234   cnt)
 235
 236 (defun nroff-backward-text-line (&optional cnt)
 237   "Go backward one nroff text line, skipping lines of nroff requests.
 238 An argument is a repeat count; negative means move forward."
 239   (interactive "p")
 240   (nroff-forward-text-line (- cnt)))
 241
 242 (defconst nroff-brace-table
 243   '((".(b" . ".)b")
 244     (".(l" . ".)l")
 245     (".(q" . ".)q")
 246     (".(c" . ".)c")
 247     (".(x" . ".)x")
 248     (".(z" . ".)z")
 249     (".(d" . ".)d")
 250     (".(f" . ".)f")
 251     (".LG" . ".NL")
 252     (".SM" . ".NL")
 253     (".LD" . ".DE")
 254     (".CD" . ".DE")
 255     (".BD" . ".DE")
 256     (".DS" . ".DE")
 257     (".DF" . ".DE")
 258     (".FS" . ".FE")
 259     (".KS" . ".KE")
 260     (".KF" . ".KE")
 261     (".LB" . ".LE")
 262     (".AL" . ".LE")
 263     (".BL" . ".LE")
 264     (".DL" . ".LE")
 265     (".ML" . ".LE")
 266     (".RL" . ".LE")
 267     (".VL" . ".LE")
 268     (".RS" . ".RE")
 269     (".TS" . ".TE")
 270     (".EQ" . ".EN")
 271     (".PS" . ".PE")
 272     (".BS" . ".BE")
 273     (".G1" . ".G2")                     ; grap
 274     (".na" . ".ad b")
 275     (".nf" . ".fi")
 276     (".de" . "..")))
 277
 278 (defun nroff-electric-newline (arg)
 279   "Insert newline for nroff mode; special if nroff-electric mode.
 280 In `nroff-electric-mode', if ending a line containing an nroff opening request,
 281 automatically inserts the matching closing request after point."
 282   (interactive "P")
 283   (let ((completion (save-excursion
 284                       (beginning-of-line)
 285                       (and (null arg)
 286                            nroff-electric-mode
 287                            (<= (point) (- (point-max) 3))
 288                            (cdr (assoc (buffer-substring (point)
 289                                                          (+ 3 (point)))
 290                                        nroff-brace-table)))))
 291         (needs-nl (not (looking-at "[ \t]*$"))))
 292     (if (null completion)
 293         (newline (prefix-numeric-value arg))
 294       (save-excursion
 295         (insert "\n\n" completion)
 296         (if needs-nl (insert "\n")))
 297       (forward-char 1))))
 298
 299 (define-minor-mode nroff-electric-mode
 300   "Toggle `nroff-electric-newline' minor mode.
 301 `nroff-electric-newline' forces Emacs to check for an nroff request at the
 302 beginning of the line, and insert the matching closing request if necessary.
 303 This command toggles that mode (off->on, on->off), with an argument,
 304 turns it on if arg is positive, otherwise off."
 305   :lighter " Electric"
 306   (or (derived-mode-p 'nroff-mode) (error "Must be in nroff mode")))
 307
 308 (declare-function Man-getpage-in-background "man" (topic))
 309
 310 (defun nroff-view ()
 311   "Run man on this file."
 312   (interactive)
 313   (require 'man)
 314   (let* ((file (buffer-file-name))
 315          (viewbuf (get-buffer (concat "*Man " file "*"))))
 316     (unless file
 317       (error "Buffer is not associated with any file"))
 318     (and (buffer-modified-p)
 319          (y-or-n-p (format "Save buffer %s first? " (buffer-name)))
 320          (save-buffer))
 321     (if viewbuf
 322         (kill-buffer viewbuf))
 323     (Man-getpage-in-background file)))
 324
 325 ;; Old names that were not namespace clean.
 326 (define-obsolete-function-alias 'count-text-lines 'nroff-count-text-lines "22.1")
 327 (define-obsolete-function-alias 'forward-text-line 'nroff-forward-text-line "22.1")
 328 (define-obsolete-function-alias 'backward-text-line 'nroff-backward-text-line "22.1")
 329 (define-obsolete-function-alias 'electric-nroff-newline 'nroff-electric-newline "22.1")
 330 (define-obsolete-function-alias 'electric-nroff-mode 'nroff-electric-mode "22.1")
 331
 332 (provide 'nroff-mode)
 333
 334 ;;; nroff-mode.el ends here