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,
41 :link
'(custom-group-link :tag
"Font Lock Faces group" font-lock-faces
)
45 (defcustom nroff-electric-mode nil
46 "*Non-nil means automatically closing requests when you insert an open."
50 (defvar nroff-mode-map
51 (let ((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?" 'count-text-lines
)
55 (define-key map
"\n" 'electric-nroff-newline
)
56 (define-key map
"\en" 'forward-text-line
)
57 (define-key map
"\ep" 'backward-text-line
)
59 "Major mode keymap for `nroff-mode'.")
61 (defvar nroff-mode-syntax-table
62 (let ((st (copy-syntax-table text-mode-syntax-table
)))
63 ;; " isn't given string quote syntax in text-mode but it
64 ;; (arguably) should be for use round nroff arguments (with ` and
66 (modify-syntax-entry ?
\" "\" 2" st
)
67 ;; Comments are delimited by \" and newline.
68 (modify-syntax-entry ?
\\ "\\ 1" st
)
69 (modify-syntax-entry ?
\n "> 1" st
)
71 "Syntax table used while in `nroff-mode'.")
73 (defvar nroff-imenu-expression
75 '((nil "^\\.SH \"?\\([^\"\n]*\\)\"?$" 1)))
77 (defcustom nroff-font-lock-keywords
79 ;; Directives are . or ' at start of line, followed by
80 ;; optional whitespace, then command (which my be longer than
81 ;; 2 characters in groff). Perhaps the arguments should be
84 ;; There are numerous groff escapes; the following get things
85 ;; like \-, \(em (standard troff) and \f[bar] (groff
86 ;; variants). This won't currently do groff's \A'foo' and
87 ;; the like properly. One might expect it to highlight an escape's
88 ;; arguments in common cases, like \f.
89 (concat "\\\\" ; backslash
90 "\\(" ; followed by various possibilities
92 '("[f*n]*\\[.+]" ; some groff extensions
93 "(.." ; two chars after (
94 "[^(\"]" ; single char escape
98 "Font-lock highlighting control in `nroff-mode'."
100 :type
'(repeat regexp
))
102 (defcustom nroff-mode-hook nil
103 "Hook run by function `nroff-mode'."
108 (define-derived-mode nroff-mode text-mode
"Nroff"
109 "Major mode for editing text intended for nroff to format.
111 Turning on Nroff mode runs `text-mode-hook', then `nroff-mode-hook'.
112 Also, try `nroff-electric-mode', for automatically inserting
113 closing requests for requests that are used in matched pairs."
114 (set (make-local-variable 'font-lock-defaults
)
115 ;; SYNTAX-BEGIN is set to backward-paragraph to avoid slow-down
116 ;; near the end of large buffers due to searching to buffer's
118 '(nroff-font-lock-keywords nil t nil backward-paragraph
))
119 (set (make-local-variable 'nroff-electric-mode
) nil
)
120 (set (make-local-variable 'outline-regexp
) "\\.H[ ]+[1-7]+ ")
121 (set (make-local-variable 'outline-level
) 'nroff-outline-level
)
122 ;; now define a bunch of variables for use by commands in this mode
123 (set (make-local-variable 'page-delimiter
) "^\\.\\(bp\\|SK\\|OP\\)")
124 (set (make-local-variable 'paragraph-start
)
125 (concat "[.']\\|" paragraph-start
))
126 (set (make-local-variable 'paragraph-separate
)
127 (concat "[.']\\|" paragraph-separate
))
128 ;; comment syntax added by mit-erl!gildea 18 Apr 86
129 (set (make-local-variable 'comment-start
) "\\\" ")
130 (set (make-local-variable 'comment-start-skip
) "\\\\\"[ \t]*")
131 (set (make-local-variable 'comment-column
) 24)
132 (set (make-local-variable 'comment-indent-function
) 'nroff-comment-indent
)
133 (set (make-local-variable 'imenu-generic-expression
) nroff-imenu-expression
))
135 (defun nroff-outline-level ()
137 (looking-at outline-regexp
)
138 (skip-chars-forward ".H ")
139 (string-to-number (buffer-substring (point) (+ 1 (point))))))
141 ;;; Compute how much to indent a comment in nroff/troff source.
142 ;;; By mit-erl!gildea April 86
143 (defun nroff-comment-indent ()
144 "Compute indent for an nroff/troff comment.
145 Puts a full-stop before comments on a line by themselves."
149 (skip-chars-backward " \t")
157 (looking-at "^[.']"))
160 (* 8 (/ (+ (current-column)
161 9) 8)))))) ; add 9 to ensure at least two blanks
164 (defun count-text-lines (start end
&optional print
)
165 "Count lines in region, except for nroff request lines.
166 All lines not starting with a period are counted up.
167 Interactively, print result in echo area.
168 Noninteractively, return number of non-request lines from START to END."
171 (message "Region has %d text lines" (count-text-lines start end
))
174 (narrow-to-region start end
)
175 (goto-char (point-min))
176 (- (buffer-size) (forward-text-line (buffer-size)))))))
178 (defun forward-text-line (&optional cnt
)
179 "Go forward one nroff text line, skipping lines of nroff requests.
180 An argument is a repeat count; if negative, move backward."
182 (if (not cnt
) (setq cnt
1))
183 (while (and (> cnt
0) (not (eobp)))
185 (while (and (not (eobp)) (looking-at "[.']."))
187 (setq cnt
(- cnt
1)))
188 (while (and (< cnt
0) (not (bobp)))
190 (while (and (not (bobp))
191 (looking-at "[.']."))
193 (setq cnt
(+ cnt
1)))
196 (defun backward-text-line (&optional cnt
)
197 "Go backward one nroff text line, skipping lines of nroff requests.
198 An argument is a repeat count; negative means move forward."
200 (forward-text-line (- cnt
)))
202 (defconst nroff-brace-table
233 (".G1" .
".G2") ; grap
238 (defun electric-nroff-newline (arg)
239 "Insert newline for nroff mode; special if electric-nroff mode.
240 In `electric-nroff-mode', if ending a line containing an nroff opening request,
241 automatically inserts the matching closing request after point."
243 (let ((completion (save-excursion
247 (<= (point) (- (point-max) 3))
248 (cdr (assoc (buffer-substring (point)
250 nroff-brace-table
)))))
251 (needs-nl (not (looking-at "[ \t]*$"))))
252 (if (null completion
)
253 (newline (prefix-numeric-value arg
))
255 (insert "\n\n" completion
)
256 (if needs-nl
(insert "\n")))
259 (defun electric-nroff-mode (&optional arg
)
260 "Toggle `nroff-electric-newline' minor mode.
261 `nroff-electric-newline' forces Emacs to check for an nroff request at the
262 beginning of the line, and insert the matching closing request if necessary.
263 This command toggles that mode (off->on, on->off), with an argument,
264 turns it on iff arg is positive, otherwise off."
266 (or (eq major-mode
'nroff-mode
) (error "Must be in nroff mode"))
267 (or (assq 'nroff-electric-mode minor-mode-alist
)
268 (setq minor-mode-alist
(append minor-mode-alist
269 (list '(nroff-electric-mode
271 (setq nroff-electric-mode
272 (cond ((null arg
) (null nroff-electric-mode
))
273 (t (> (prefix-numeric-value arg
) 0)))))
275 (provide 'nroff-mode
)
277 ;;; arch-tag: 6e276340-6c65-4f65-b4e3-0ca431ddfb6c
278 ;;; nroff-mode.el ends here