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emacs/lisp/textmodes/nroff-mode.el
2005-07-04 16:49:24 +00:00

277 lines
9.4 KiB
EmacsLisp

;;; nroff-mode.el --- GNU Emacs major mode for editing nroff source
;; Copyright (C) 1985, 86, 94, 95, 97, 2001 Free Software Foundation, Inc.
;; Maintainer: FSF
;; Keywords: wp
;; This file is part of GNU Emacs.
;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.
;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;; GNU General Public License for more details.
;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING. If not, write to the
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.
;;; Commentary:
;; This package is a major mode for editing nroff source code. It knows
;; about various nroff constructs, ms, mm, and me macros, and will fill
;; and indent paragraphs properly in their presence. It also includes
;; a command to count text lines (excluding nroff constructs), a command
;; to center a line, and movement commands that know how to skip macros.
;; Paragraph filling and line-counting currently don't respect comments,
;; as they should.
;;; Code:
(defgroup nroff nil
"Nroff mode."
:group 'wp
:prefix "nroff-")
(defcustom nroff-electric-mode nil
"*Non-nil means automatically closing requests when you insert an open."
:group 'nroff
:type 'boolean)
(defvar nroff-mode-map
(let ((map (make-sparse-keymap)))
(define-key map "\t" 'tab-to-tab-stop)
(define-key map "\es" 'center-line)
(define-key map "\e?" 'count-text-lines)
(define-key map "\n" 'electric-nroff-newline)
(define-key map "\en" 'forward-text-line)
(define-key map "\ep" 'backward-text-line)
map)
"Major mode keymap for `nroff-mode'.")
(defvar nroff-mode-syntax-table
(let ((st (copy-syntax-table text-mode-syntax-table)))
;; " isn't given string quote syntax in text-mode but it
;; (arguably) should be for use round nroff arguments (with ` and
;; ' used otherwise).
(modify-syntax-entry ?\" "\" 2" st)
;; Comments are delimited by \" and newline.
(modify-syntax-entry ?\\ "\\ 1" st)
(modify-syntax-entry ?\n "> 1" st)
st)
"Syntax table used while in `nroff-mode'.")
(defvar nroff-imenu-expression
;; man headers:
'((nil "^\\.SH \"?\\([^\"\n]*\\)\"?$" 1)))
(defcustom nroff-font-lock-keywords
(list
;; Directives are . or ' at start of line, followed by
;; optional whitespace, then command (which my be longer than
;; 2 characters in groff). Perhaps the arguments should be
;; fontified as well.
"^[.']\\s-*\\sw+"
;; There are numerous groff escapes; the following get things
;; like \-, \(em (standard troff) and \f[bar] (groff
;; variants). This won't currently do groff's \A'foo' and
;; the like properly. One might expect it to highlight an escape's
;; arguments in common cases, like \f.
(concat "\\\\" ; backslash
"\\(" ; followed by various possibilities
(mapconcat 'identity
'("[f*n]*\\[.+]" ; some groff extensions
"(.." ; two chars after (
"[^(\"]" ; single char escape
) "\\|")
"\\)")
)
"Font-lock highlighting control in `nroff-mode'."
:group 'nroff
:type '(repeat regexp))
(defcustom nroff-mode-hook nil
"Hook run by function `nroff-mode'."
:type 'hook
:group 'nroff)
;;;###autoload
(define-derived-mode nroff-mode text-mode "Nroff"
"Major mode for editing text intended for nroff to format.
\\{nroff-mode-map}
Turning on Nroff mode runs `text-mode-hook', then `nroff-mode-hook'.
Also, try `nroff-electric-mode', for automatically inserting
closing requests for requests that are used in matched pairs."
(set (make-local-variable 'font-lock-defaults)
;; SYNTAX-BEGIN is set to backward-paragraph to avoid slow-down
;; near the end of large buffers due to searching to buffer's
;; beginning.
'(nroff-font-lock-keywords nil t nil backward-paragraph))
(set (make-local-variable 'nroff-electric-mode) nil)
(set (make-local-variable 'outline-regexp) "\\.H[ ]+[1-7]+ ")
(set (make-local-variable 'outline-level) 'nroff-outline-level)
;; now define a bunch of variables for use by commands in this mode
(set (make-local-variable 'page-delimiter) "^\\.\\(bp\\|SK\\|OP\\)")
(set (make-local-variable 'paragraph-start)
(concat "[.']\\|" paragraph-start))
(set (make-local-variable 'paragraph-separate)
(concat "[.']\\|" paragraph-separate))
;; comment syntax added by mit-erl!gildea 18 Apr 86
(set (make-local-variable 'comment-start) "\\\" ")
(set (make-local-variable 'comment-start-skip) "\\\\\"[ \t]*")
(set (make-local-variable 'comment-column) 24)
(set (make-local-variable 'comment-indent-function) 'nroff-comment-indent)
(set (make-local-variable 'imenu-generic-expression) nroff-imenu-expression))
(defun nroff-outline-level ()
(save-excursion
(looking-at outline-regexp)
(skip-chars-forward ".H ")
(string-to-number (buffer-substring (point) (+ 1 (point))))))
;;; Compute how much to indent a comment in nroff/troff source.
;;; By mit-erl!gildea April 86
(defun nroff-comment-indent ()
"Compute indent for an nroff/troff comment.
Puts a full-stop before comments on a line by themselves."
(let ((pt (point)))
(unwind-protect
(progn
(skip-chars-backward " \t")
(if (bolp)
(progn
(setq pt (1+ pt))
(insert ?.)
1)
(if (save-excursion
(backward-char 1)
(looking-at "^[.']"))
1
(max comment-column
(* 8 (/ (+ (current-column)
9) 8)))))) ; add 9 to ensure at least two blanks
(goto-char pt))))
(defun count-text-lines (start end &optional print)
"Count lines in region, except for nroff request lines.
All lines not starting with a period are counted up.
Interactively, print result in echo area.
Noninteractively, return number of non-request lines from START to END."
(interactive "r\np")
(if print
(message "Region has %d text lines" (count-text-lines start end))
(save-excursion
(save-restriction
(narrow-to-region start end)
(goto-char (point-min))
(- (buffer-size) (forward-text-line (buffer-size)))))))
(defun forward-text-line (&optional cnt)
"Go forward one nroff text line, skipping lines of nroff requests.
An argument is a repeat count; if negative, move backward."
(interactive "p")
(if (not cnt) (setq cnt 1))
(while (and (> cnt 0) (not (eobp)))
(forward-line 1)
(while (and (not (eobp)) (looking-at "[.']."))
(forward-line 1))
(setq cnt (- cnt 1)))
(while (and (< cnt 0) (not (bobp)))
(forward-line -1)
(while (and (not (bobp))
(looking-at "[.']."))
(forward-line -1))
(setq cnt (+ cnt 1)))
cnt)
(defun backward-text-line (&optional cnt)
"Go backward one nroff text line, skipping lines of nroff requests.
An argument is a repeat count; negative means move forward."
(interactive "p")
(forward-text-line (- cnt)))
(defconst nroff-brace-table
'((".(b" . ".)b")
(".(l" . ".)l")
(".(q" . ".)q")
(".(c" . ".)c")
(".(x" . ".)x")
(".(z" . ".)z")
(".(d" . ".)d")
(".(f" . ".)f")
(".LG" . ".NL")
(".SM" . ".NL")
(".LD" . ".DE")
(".CD" . ".DE")
(".BD" . ".DE")
(".DS" . ".DE")
(".DF" . ".DE")
(".FS" . ".FE")
(".KS" . ".KE")
(".KF" . ".KE")
(".LB" . ".LE")
(".AL" . ".LE")
(".BL" . ".LE")
(".DL" . ".LE")
(".ML" . ".LE")
(".RL" . ".LE")
(".VL" . ".LE")
(".RS" . ".RE")
(".TS" . ".TE")
(".EQ" . ".EN")
(".PS" . ".PE")
(".BS" . ".BE")
(".G1" . ".G2") ; grap
(".na" . ".ad b")
(".nf" . ".fi")
(".de" . "..")))
(defun electric-nroff-newline (arg)
"Insert newline for nroff mode; special if electric-nroff mode.
In `electric-nroff-mode', if ending a line containing an nroff opening request,
automatically inserts the matching closing request after point."
(interactive "P")
(let ((completion (save-excursion
(beginning-of-line)
(and (null arg)
nroff-electric-mode
(<= (point) (- (point-max) 3))
(cdr (assoc (buffer-substring (point)
(+ 3 (point)))
nroff-brace-table)))))
(needs-nl (not (looking-at "[ \t]*$"))))
(if (null completion)
(newline (prefix-numeric-value arg))
(save-excursion
(insert "\n\n" completion)
(if needs-nl (insert "\n")))
(forward-char 1))))
(defun electric-nroff-mode (&optional arg)
"Toggle `nroff-electric-newline' minor mode.
`nroff-electric-newline' forces Emacs to check for an nroff request at the
beginning of the line, and insert the matching closing request if necessary.
This command toggles that mode (off->on, on->off), with an argument,
turns it on iff arg is positive, otherwise off."
(interactive "P")
(or (eq major-mode 'nroff-mode) (error "Must be in nroff mode"))
(or (assq 'nroff-electric-mode minor-mode-alist)
(setq minor-mode-alist (append minor-mode-alist
(list '(nroff-electric-mode
" Electric")))))
(setq nroff-electric-mode
(cond ((null arg) (null nroff-electric-mode))
(t (> (prefix-numeric-value arg) 0)))))
(provide 'nroff-mode)
;;; arch-tag: 6e276340-6c65-4f65-b4e3-0ca431ddfb6c
;;; nroff-mode.el ends here