lisp/textmodes/nroff-mode.el

   1 ;; GNU Emacs major mode for editing nroff source
   2 ;; Copyright (C) 1985, 1986 Free Software Foundation, Inc.
   3
   4 ;; This file is part of GNU Emacs.
   5
   6 ;; GNU Emacs is free software; you can redistribute it and/or modify
   7 ;; it under the terms of the GNU General Public License as published by
   8 ;; the Free Software Foundation; either version 1, or (at your option)
   9 ;; any later version.
  10
  11 ;; GNU Emacs is distributed in the hope that it will be useful,
  12 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 ;; GNU General Public License for more details.
  15
  16 ;; You should have received a copy of the GNU General Public License
  17 ;; along with GNU Emacs; see the file COPYING.  If not, write to
  18 ;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20
  21
  22 (defvar nroff-mode-abbrev-table nil
  23   "Abbrev table used while in nroff mode.")
  24
  25 (defvar nroff-mode-map nil
  26      "Major mode keymap for nroff mode.")
  27 (if (not nroff-mode-map)
  28     (progn
  29       (setq nroff-mode-map (make-sparse-keymap))
  30       (define-key nroff-mode-map "\t"  'tab-to-tab-stop)
  31       (define-key nroff-mode-map "\es" 'center-line)
  32       (define-key nroff-mode-map "\e?" 'count-text-lines)
  33       (define-key nroff-mode-map "\n"  'electric-nroff-newline)
  34       (define-key nroff-mode-map "\en" 'forward-text-line)
  35       (define-key nroff-mode-map "\ep" 'backward-text-line)))
  36
  37 (defun nroff-mode ()
  38   "Major mode for editing text intended for nroff to format.
  39 \\{nroff-mode-map}
  40 Turning on Nroff mode runs `text-mode-hook', then `nroff-mode-hook'.
  41 Also, try `nroff-electric-mode', for automatically inserting
  42 closing requests for requests that are used in matched pairs."
  43   (interactive)
  44   (kill-all-local-variables)
  45   (use-local-map nroff-mode-map)
  46   (setq mode-name "Nroff")
  47   (setq major-mode 'nroff-mode)
  48   (set-syntax-table text-mode-syntax-table)
  49   (setq local-abbrev-table nroff-mode-abbrev-table)
  50   (make-local-variable 'nroff-electric-mode)
  51   ;; now define a bunch of variables for use by commands in this mode
  52   (make-local-variable 'page-delimiter)
  53   (setq page-delimiter "^\\.\\(bp\\|SK\\|OP\\)")
  54   (make-local-variable 'paragraph-start)
  55   (setq paragraph-start (concat "^[.']\\|" paragraph-start))
  56   (make-local-variable 'paragraph-separate)
  57   (setq paragraph-separate (concat "^[.']\\|" paragraph-separate))
  58   ;; comment syntax added by mit-erl!gildea 18 Apr 86
  59   (make-local-variable 'comment-start)
  60   (setq comment-start "\\\" ")
  61   (make-local-variable 'comment-start-skip)
  62   (setq comment-start-skip "\\\\\"[ \t]*")
  63   (make-local-variable 'comment-column)
  64   (setq comment-column 24)
  65   (make-local-variable 'comment-indent-hook)
  66   (setq comment-indent-hook 'nroff-comment-indent)
  67   (run-hooks 'text-mode-hook 'nroff-mode-hook))
  68
  69 ;;; Compute how much to indent a comment in nroff/troff source.
  70 ;;; By mit-erl!gildea April 86
  71 (defun nroff-comment-indent ()
  72   "Compute indent for an nroff/troff comment.
  73 Puts a full-stop before comments on a line by themselves."
  74   (let ((pt (point)))
  75     (unwind-protect
  76         (progn
  77           (skip-chars-backward " \t")
  78           (if (bolp)
  79               (progn
  80                 (setq pt (1+ pt))
  81                 (insert ?.)
  82                 1)
  83             (if (save-excursion
  84                   (backward-char 1)
  85                   (looking-at "^[.']"))
  86                 1
  87               (max comment-column
  88                    (* 8 (/ (+ (current-column)
  89                               9) 8)))))) ; add 9 to ensure at least two blanks
  90       (goto-char pt))))
  91
  92 (defun count-text-lines (start end &optional print)
  93   "Count lines in region, except for nroff request lines.
  94 All lines not starting with a period are counted up.
  95 Interactively, print result in echo area.
  96 Noninteractively, return number of non-request lines from START to END."
  97   (interactive "r\np")
  98   (if print
  99       (message "Region has %d text lines" (count-text-lines start end))
 100     (save-excursion
 101       (save-restriction
 102         (narrow-to-region start end)
 103         (goto-char (point-min))
 104         (- (buffer-size) (forward-text-line (buffer-size)))))))
 105
 106 (defun forward-text-line (&optional cnt)
 107   "Go forward one nroff text line, skipping lines of nroff requests.
 108 An argument is a repeat count; if negative, move backward."
 109   (interactive "p")
 110   (if (not cnt) (setq cnt 1))
 111   (while (and (> cnt 0) (not (eobp)))
 112     (forward-line 1)
 113     (while (and (not (eobp)) (looking-at "[.']."))
 114       (forward-line 1))
 115     (setq cnt (- cnt 1)))
 116   (while (and (< cnt 0) (not (bobp)))
 117     (forward-line -1)
 118     (while (and (not (bobp))
 119                 (looking-at "[.']."))
 120       (forward-line -1))
 121     (setq cnt (+ cnt 1)))
 122   cnt)
 123
 124 (defun backward-text-line (&optional cnt)
 125   "Go backward one nroff text line, skipping lines of nroff requests.
 126 An argument is a repeat count; negative means move forward."
 127   (interactive "p")
 128   (forward-text-line (- cnt)))
 129
 130 (defconst nroff-brace-table
 131   '((".(b" . ".)b")
 132     (".(l" . ".)l")
 133     (".(q" . ".)q")
 134     (".(c" . ".)c")
 135     (".(x" . ".)x")
 136     (".(z" . ".)z")
 137     (".(d" . ".)d")
 138     (".(f" . ".)f")
 139     (".LG" . ".NL")
 140     (".SM" . ".NL")
 141     (".LD" . ".DE")
 142     (".CD" . ".DE")
 143     (".BD" . ".DE")
 144     (".DS" . ".DE")
 145     (".DF" . ".DE")
 146     (".FS" . ".FE")
 147     (".KS" . ".KE")
 148     (".KF" . ".KE")
 149     (".LB" . ".LE")
 150     (".AL" . ".LE")
 151     (".BL" . ".LE")
 152     (".DL" . ".LE")
 153     (".ML" . ".LE")
 154     (".RL" . ".LE")
 155     (".VL" . ".LE")
 156     (".RS" . ".RE")
 157     (".TS" . ".TE")
 158     (".EQ" . ".EN")
 159     (".PS" . ".PE")
 160     (".BS" . ".BE")
 161     (".G1" . ".G2")                     ; grap
 162     (".na" . ".ad b")
 163     (".nf" . ".fi")
 164     (".de" . "..")))
 165
 166 (defun electric-nroff-newline (arg)
 167   "Insert newline for nroff mode; special if electric-nroff mode.
 168 In `electric-nroff-mode', if ending a line containing an nroff opening request,
 169 automatically inserts the matching closing request after point."
 170   (interactive "P")
 171   (let ((completion (save-excursion
 172                       (beginning-of-line)
 173                       (and (null arg)
 174                            nroff-electric-mode
 175                            (<= (point) (- (point-max) 3))
 176                            (cdr (assoc (buffer-substring (point)
 177                                                          (+ 3 (point)))
 178                                        nroff-brace-table)))))
 179         (needs-nl (not (looking-at "[ \t]*$"))))
 180     (if (null completion)
 181         (newline (prefix-numeric-value arg))
 182       (save-excursion
 183         (insert "\n\n" completion)
 184         (if needs-nl (insert "\n")))
 185       (forward-char 1))))
 186
 187 (defun electric-nroff-mode (&optional arg)
 188   "Toggle `nroff-electric-newline' minor mode.
 189 `nroff-electric-newline' forces Emacs to check for an nroff request at the
 190 beginning of the line, and insert the matching closing request if necessary.
 191 This command toggles that mode (off->on, on->off), with an argument,
 192 turns it on iff arg is positive, otherwise off."
 193   (interactive "P")
 194   (or (eq major-mode 'nroff-mode) (error "Must be in nroff mode"))
 195   (or (assq 'nroff-electric-mode minor-mode-alist)
 196       (setq minor-mode-alist (append minor-mode-alist
 197                                      (list '(nroff-electric-mode
 198                                              " Electric")))))
 199   (setq nroff-electric-mode
 200         (cond ((null arg) (null nroff-electric-mode))
 201               (t (> (prefix-numeric-value arg) 0)))))
 202