1 ;;; nroff-mode.el --- GNU Emacs major mode for editing nroff source
3 ;; Copyright (C) 1985, 1986, 1994, 1995, 1997, 2001, 2002, 2003,
4 ;; 2004, 2005 Free Software Foundation, Inc.
9 ;; This file is part of GNU Emacs.
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 2, or (at your option)
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.
21 ;; You should have received a copy of the GNU General Public License
22 ;; along with GNU Emacs; see the file COPYING. If not, write to the
23 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
24 ;; Boston, MA 02110-1301, USA.
28 ;; This package is a major mode for editing nroff source code. It knows
29 ;; about various nroff constructs, ms, mm, and me macros, and will fill
30 ;; and indent paragraphs properly in their presence. It also includes
31 ;; a command to count text lines (excluding nroff constructs), a command
32 ;; to center a line, and movement commands that know how to skip macros.
34 ;; Paragraph filling and line-counting currently don't respect comments,
44 (defcustom nroff-electric-mode nil
45 "*Non-nil means automatically closing requests when you insert an open."
49 (defvar nroff-mode-map
50 (let ((map (make-sparse-keymap)))
51 (define-key map
"\t" 'tab-to-tab-stop
)
52 (define-key map
"\es" 'center-line
)
53 (define-key map
"\e?" 'count-text-lines
)
54 (define-key map
"\n" 'electric-nroff-newline
)
55 (define-key map
"\en" 'forward-text-line
)
56 (define-key map
"\ep" 'backward-text-line
)
58 "Major mode keymap for `nroff-mode'.")
60 (defvar nroff-mode-syntax-table
61 (let ((st (copy-syntax-table text-mode-syntax-table
)))
62 ;; " isn't given string quote syntax in text-mode but it
63 ;; (arguably) should be for use round nroff arguments (with ` and
65 (modify-syntax-entry ?
\" "\" 2" st
)
66 ;; Comments are delimited by \" and newline.
67 (modify-syntax-entry ?
\\ "\\ 1" st
)
68 (modify-syntax-entry ?
\n "> 1" st
)
70 "Syntax table used while in `nroff-mode'.")
72 (defvar nroff-imenu-expression
74 '((nil "^\\.SH \"?\\([^\"\n]*\\)\"?$" 1)))
76 (defcustom nroff-font-lock-keywords
78 ;; Directives are . or ' at start of line, followed by
79 ;; optional whitespace, then command (which my be longer than
80 ;; 2 characters in groff). Perhaps the arguments should be
83 ;; There are numerous groff escapes; the following get things
84 ;; like \-, \(em (standard troff) and \f[bar] (groff
85 ;; variants). This won't currently do groff's \A'foo' and
86 ;; the like properly. One might expect it to highlight an escape's
87 ;; arguments in common cases, like \f.
88 (concat "\\\\" ; backslash
89 "\\(" ; followed by various possibilities
91 '("[f*n]*\\[.+]" ; some groff extensions
92 "(.." ; two chars after (
93 "[^(\"]" ; single char escape
97 "Font-lock highlighting control in `nroff-mode'."
99 :type
'(repeat regexp
))
101 (defcustom nroff-mode-hook nil
102 "Hook run by function `nroff-mode'."
107 (define-derived-mode nroff-mode text-mode
"Nroff"
108 "Major mode for editing text intended for nroff to format.
110 Turning on Nroff mode runs `text-mode-hook', then `nroff-mode-hook'.
111 Also, try `nroff-electric-mode', for automatically inserting
112 closing requests for requests that are used in matched pairs."
113 (set (make-local-variable 'font-lock-defaults
)
114 ;; SYNTAX-BEGIN is set to backward-paragraph to avoid slow-down
115 ;; near the end of large buffers due to searching to buffer's
117 '(nroff-font-lock-keywords nil t nil backward-paragraph
))
118 (set (make-local-variable 'nroff-electric-mode
) nil
)
119 (set (make-local-variable 'outline-regexp
) "\\.H[ ]+[1-7]+ ")
120 (set (make-local-variable 'outline-level
) 'nroff-outline-level
)
121 ;; now define a bunch of variables for use by commands in this mode
122 (set (make-local-variable 'page-delimiter
) "^\\.\\(bp\\|SK\\|OP\\)")
123 (set (make-local-variable 'paragraph-start
)
124 (concat "[.']\\|" paragraph-start
))
125 (set (make-local-variable 'paragraph-separate
)
126 (concat "[.']\\|" paragraph-separate
))
127 ;; comment syntax added by mit-erl!gildea 18 Apr 86
128 (set (make-local-variable 'comment-start
) "\\\" ")
129 (set (make-local-variable 'comment-start-skip
) "\\\\\"[ \t]*")
130 (set (make-local-variable 'comment-column
) 24)
131 (set (make-local-variable 'comment-indent-function
) 'nroff-comment-indent
)
132 (set (make-local-variable 'imenu-generic-expression
) nroff-imenu-expression
))
134 (defun nroff-outline-level ()
136 (looking-at outline-regexp
)
137 (skip-chars-forward ".H ")
138 (string-to-number (buffer-substring (point) (+ 1 (point))))))
140 ;;; Compute how much to indent a comment in nroff/troff source.
141 ;;; By mit-erl!gildea April 86
142 (defun nroff-comment-indent ()
143 "Compute indent for an nroff/troff comment.
144 Puts a full-stop before comments on a line by themselves."
148 (skip-chars-backward " \t")
156 (looking-at "^[.']"))
159 (* 8 (/ (+ (current-column)
160 9) 8)))))) ; add 9 to ensure at least two blanks
163 (defun count-text-lines (start end
&optional print
)
164 "Count lines in region, except for nroff request lines.
165 All lines not starting with a period are counted up.
166 Interactively, print result in echo area.
167 Noninteractively, return number of non-request lines from START to END."
170 (message "Region has %d text lines" (count-text-lines start end
))
173 (narrow-to-region start end
)
174 (goto-char (point-min))
175 (- (buffer-size) (forward-text-line (buffer-size)))))))
177 (defun forward-text-line (&optional cnt
)
178 "Go forward one nroff text line, skipping lines of nroff requests.
179 An argument is a repeat count; if negative, move backward."
181 (if (not cnt
) (setq cnt
1))
182 (while (and (> cnt
0) (not (eobp)))
184 (while (and (not (eobp)) (looking-at "[.']."))
186 (setq cnt
(- cnt
1)))
187 (while (and (< cnt
0) (not (bobp)))
189 (while (and (not (bobp))
190 (looking-at "[.']."))
192 (setq cnt
(+ cnt
1)))
195 (defun backward-text-line (&optional cnt
)
196 "Go backward one nroff text line, skipping lines of nroff requests.
197 An argument is a repeat count; negative means move forward."
199 (forward-text-line (- cnt
)))
201 (defconst nroff-brace-table
232 (".G1" .
".G2") ; grap
237 (defun electric-nroff-newline (arg)
238 "Insert newline for nroff mode; special if electric-nroff mode.
239 In `electric-nroff-mode', if ending a line containing an nroff opening request,
240 automatically inserts the matching closing request after point."
242 (let ((completion (save-excursion
246 (<= (point) (- (point-max) 3))
247 (cdr (assoc (buffer-substring (point)
249 nroff-brace-table
)))))
250 (needs-nl (not (looking-at "[ \t]*$"))))
251 (if (null completion
)
252 (newline (prefix-numeric-value arg
))
254 (insert "\n\n" completion
)
255 (if needs-nl
(insert "\n")))
258 (defun electric-nroff-mode (&optional arg
)
259 "Toggle `nroff-electric-newline' minor mode.
260 `nroff-electric-newline' forces Emacs to check for an nroff request at the
261 beginning of the line, and insert the matching closing request if necessary.
262 This command toggles that mode (off->on, on->off), with an argument,
263 turns it on iff arg is positive, otherwise off."
265 (or (eq major-mode
'nroff-mode
) (error "Must be in nroff mode"))
266 (or (assq 'nroff-electric-mode minor-mode-alist
)
267 (setq minor-mode-alist
(append minor-mode-alist
268 (list '(nroff-electric-mode
270 (setq nroff-electric-mode
271 (cond ((null arg
) (null nroff-electric-mode
))
272 (t (> (prefix-numeric-value arg
) 0)))))
274 (provide 'nroff-mode
)
276 ;;; arch-tag: 6e276340-6c65-4f65-b4e3-0ca431ddfb6c
277 ;;; nroff-mode.el ends here