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, 2006 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)
46 (defcustom nroff-electric-mode nil
47 "Non-nil means automatically closing requests when you insert an open."
51 (defvar nroff-mode-map
52 (let ((map (make-sparse-keymap)))
53 (define-key map "\t" 'tab-to-tab-stop)
54 (define-key map "\es" 'center-line)
55 (define-key map "\e?" 'nroff-count-text-lines)
56 (define-key map "\n" 'nroff-electric-newline)
57 (define-key map "\en" 'nroff-forward-text-line)
58 (define-key map "\ep" 'nroff-backward-text-line)
60 "Major mode keymap for `nroff-mode'.")
62 (defvar nroff-mode-syntax-table
63 (let ((st (copy-syntax-table text-mode-syntax-table)))
64 ;; " isn't given string quote syntax in text-mode but it
65 ;; (arguably) should be for use round nroff arguments (with ` and
67 (modify-syntax-entry ?\" "\" 2" st)
68 ;; Comments are delimited by \" and newline.
69 (modify-syntax-entry ?\\ "\\ 1" st)
70 (modify-syntax-entry ?\n ">" st)
72 "Syntax table used while in `nroff-mode'.")
74 (defvar nroff-imenu-expression
76 '((nil "^\\.SH \"?\\([^\"\n]*\\)\"?$" 1)))
78 (defcustom nroff-font-lock-keywords
80 ;; Directives are . or ' at start of line, followed by
81 ;; optional whitespace, then command (which my be longer than
82 ;; 2 characters in groff). Perhaps the arguments should be
85 ;; There are numerous groff escapes; the following get things
86 ;; like \-, \(em (standard troff) and \f[bar] (groff
87 ;; variants). This won't currently do groff's \A'foo' and
88 ;; the like properly. One might expect it to highlight an escape's
89 ;; arguments in common cases, like \f.
90 (concat "\\\\" ; backslash
91 "\\(" ; followed by various possibilities
93 '("[f*n]*\\[.+?]" ; some groff extensions
94 "(.." ; two chars after (
95 "[^(\"]" ; single char escape
99 "Font-lock highlighting control in `nroff-mode'."
101 :type '(repeat regexp))
103 (defcustom nroff-mode-hook nil
104 "Hook run by function `nroff-mode'."
109 (define-derived-mode nroff-mode text-mode "Nroff"
110 "Major mode for editing text intended for nroff to format.
112 Turning on Nroff mode runs `text-mode-hook', then `nroff-mode-hook'.
113 Also, try `nroff-electric-mode', for automatically inserting
114 closing requests for requests that are used in matched pairs."
115 (set (make-local-variable 'font-lock-defaults)
116 ;; SYNTAX-BEGIN is set to backward-paragraph to avoid slow-down
117 ;; near the end of large buffers due to searching to buffer's
119 '(nroff-font-lock-keywords nil t nil backward-paragraph))
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 nroff-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" (nroff-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 nroff-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 nroff-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 (nroff-forward-text-line (- cnt)))
202 (defconst nroff-brace-table
233 (".G1" . ".G2") ; grap
238 (defun nroff-electric-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 (define-minor-mode nroff-electric-mode
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 (derived-mode-p 'nroff-mode) (error "Must be in nroff mode")))
268 ;; Old names that were not namespace clean.
269 (define-obsolete-function-alias 'count-text-lines 'nroff-count-text-lines "22.1")
270 (define-obsolete-function-alias 'forward-text-line 'nroff-forward-text-line "22.1")
271 (define-obsolete-function-alias 'backward-text-line 'nroff-backward-text-line "22.1")
272 (define-obsolete-function-alias 'electric-nroff-newline 'nroff-electric-newline "22.1")
273 (define-obsolete-function-alias 'electric-nroff-mode 'nroff-electric-mode "22.1")
275 (provide 'nroff-mode)
277 ;; arch-tag: 6e276340-6c65-4f65-b4e3-0ca431ddfb6c
278 ;;; nroff-mode.el ends here