[bpt/emacs.git] / lisp / textmodes / paragraphs.el

;;; paragraphs.el --- paragraph and sentence parsing.

;; Copyright (C) 1985, 86, 87, 1991 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, 675 Mass Ave, Cambridge, MA 02139, USA.

;;; Commentary:

;; This package provides the paragraph-oriented commands documented in the
;; Emacs manual.

;;; Code:

(defconst paragraph-start "^[ \t\n\f]" "\
*Regexp for beginning of a line that starts OR separates paragraphs.")

(defconst paragraph-separate "^[ \t\f]*$" "\
*Regexp for beginning of a line that separates paragraphs.
If you change this, you may have to change paragraph-start also.")

(defconst sentence-end (purecopy "[.?!][]\"')}]*\\($\\| $\\|\t\\|  \\)[ \t\n]*") "\
*Regexp describing the end of a sentence.
All paragraph boundaries also end sentences, regardless.

In order to be recognized as the end of a sentence, the ending period,
question mark, or exclamation point must be followed by two spaces,
unless it's inside some sort of quotes or parenthesis.")

(defconst page-delimiter "^\014" "\
*Regexp describing line-beginnings that separate pages.")

(defvar paragraph-ignore-fill-prefix nil "\
Non-nil means the paragraph commands are not affected by `fill-prefix'.
This is desirable in modes where blank lines are the paragraph delimiters.")


(defun forward-paragraph (&optional arg)
  "Move forward to end of paragraph.
With arg N, do it N times; negative arg -N means move forward N paragraphs.

A line which `paragraph-start' matches either separates paragraphs
\(if `paragraph-separate' matches it also) or is the first line of a paragraph.
A paragraph end is the beginning of a line which is not part of the paragraph
to which the end of the previous line belongs, or the end of the buffer."
  (interactive "p")
  (or arg (setq arg 1))
  (let* ((fill-prefix-regexp
	  (and fill-prefix (not (equal fill-prefix ""))
	       (not paragraph-ignore-fill-prefix)
	       (regexp-quote fill-prefix)))
	 (paragraph-separate
	  (if fill-prefix-regexp
	      (concat paragraph-separate "\\|^"
		      fill-prefix-regexp "[ \t]*$")
	    paragraph-separate)))
    (while (< arg 0)
      (if (and (not (looking-at paragraph-separate))
	       (re-search-backward "^\n" (max (1- (point)) (point-min)) t))
	  nil
	(forward-char -1) (beginning-of-line)
	(while (and (not (bobp)) (looking-at paragraph-separate))
	  (forward-line -1))
	(end-of-line)
	;; Search back for line that starts or separates paragraphs.
	(if (if fill-prefix-regexp
		;; There is a fill prefix; it overrides paragraph-start.
		(progn
		 (while (progn (beginning-of-line)
			       (and (not (bobp))
				    (not (looking-at paragraph-separate))
				    (looking-at fill-prefix-regexp)))
		   (forward-line -1))
		 (not (bobp)))
	      (re-search-backward paragraph-start nil t))
	    ;; Found one.
	    (progn
	      (while (and (not (eobp)) (looking-at paragraph-separate))
		(forward-line 1))
	      (if (eq (char-after (- (point) 2)) ?\n)
		  (forward-line -1)))
	  ;; No starter or separator line => use buffer beg.
	  (goto-char (point-min))))
      (setq arg (1+ arg)))
    (while (> arg 0)
      (beginning-of-line)
      (while (prog1 (and (not (eobp))
			 (looking-at paragraph-separate))
		    (forward-line 1)))
      (if fill-prefix-regexp
	  ;; There is a fill prefix; it overrides paragraph-start.
	  (while (and (not (eobp))
		      (not (looking-at paragraph-separate))
		      (looking-at fill-prefix-regexp))
	    (forward-line 1))
	(if (re-search-forward paragraph-start nil t)
	    (goto-char (match-beginning 0))
	  (goto-char (point-max))))
      (setq arg (1- arg)))))

(defun backward-paragraph (&optional arg)
  "Move backward to start of paragraph.
With arg N, do it N times; negative arg -N means move forward N paragraphs.

A paragraph start is the beginning of a line which is a
`first-line-of-paragraph' or which is ordinary text and follows a
paragraph-separating line; except: if the first real line of a
paragraph is preceded by a blank line, the paragraph starts at that
blank line.

See `forward-paragraph' for more information."
  (interactive "p")
  (or arg (setq arg 1))
  (forward-paragraph (- arg)))

(defun mark-paragraph ()
  "Put point at beginning of this paragraph, mark at end.
The paragraph marked is the one that contains point or follows point."
  (interactive)
  (forward-paragraph 1)
  (push-mark nil t t)
  (backward-paragraph 1))

(defun kill-paragraph (arg)
  "Kill forward to end of paragraph.
With arg N, kill forward to Nth end of paragraph;
negative arg -N means kill backward to Nth start of paragraph."
  (interactive "p")
  (kill-region (point) (save-excursion (forward-paragraph arg) (point))))

(defun backward-kill-paragraph (arg)
  "Kill back to start of paragraph.
With arg N, kill back to Nth start of paragraph;
negative arg -N means kill forward to Nth end of paragraph."
  (interactive "p")
  (kill-region (point) (save-excursion (backward-paragraph arg) (point))))

(defun transpose-paragraphs (arg)
  "Interchange this (or next) paragraph with previous one."
  (interactive "*p")
  (transpose-subr 'forward-paragraph arg))

(defun start-of-paragraph-text ()
  (let ((opoint (point)) npoint)
    (forward-paragraph -1)
    (setq npoint (point))
    (skip-chars-forward " \t\n")
    ;; If the range of blank lines found spans the original start point,
    ;; try again from the beginning of it.
    ;; Must be careful to avoid infinite loop
    ;; when following a single return at start of buffer.
    (if (and (>= (point) opoint) (< npoint opoint))
	(progn
	  (goto-char npoint)
	  (if (> npoint (point-min))
	      (start-of-paragraph-text))))))

(defun end-of-paragraph-text ()
  (let ((opoint (point)))
    (forward-paragraph 1)
    (if (eq (preceding-char) ?\n) (forward-char -1))
    (if (<= (point) opoint)
	(progn
	  (forward-char 1)
	  (if (< (point) (point-max))
	      (end-of-paragraph-text))))))

(defun forward-sentence (&optional arg)
  "Move forward to next `sentence-end'.  With argument, repeat.
With negative argument, move backward repeatedly to `sentence-beginning'.

The variable `sentence-end' is a regular expression that matches ends of
sentences.  Also, every paragraph boundary terminates sentences as well."
  (interactive "p")
  (or arg (setq arg 1))
  (while (< arg 0)
    (let ((par-beg (save-excursion (start-of-paragraph-text) (point))))
      (if (re-search-backward (concat sentence-end "[^ \t\n]") par-beg t)
	  (goto-char (1- (match-end 0)))
	(goto-char par-beg)))
    (setq arg (1+ arg)))
  (while (> arg 0)
    (let ((par-end (save-excursion (end-of-paragraph-text) (point))))
      (if (re-search-forward sentence-end par-end t)
	  (skip-chars-backward " \t\n")
	(goto-char par-end)))
    (setq arg (1- arg))))

(defun backward-sentence (&optional arg)
  "Move backward to start of sentence.  With arg, do it arg times.
See `forward-sentence' for more information."
  (interactive "p")
  (or arg (setq arg 1))
  (forward-sentence (- arg)))

(defun kill-sentence (&optional arg)
  "Kill from point to end of sentence.
With arg, repeat; negative arg -N means kill back to Nth start of sentence."
  (interactive "*p")
  (kill-region (point) (save-excursion (forward-sentence arg) (point))))

(defun backward-kill-sentence (&optional arg)
  "Kill back from point to start of sentence.
With arg, repeat, or kill forward to Nth end of sentence if negative arg -N."
  (interactive "*p")
  (kill-region (point) (save-excursion (backward-sentence arg) (point))))

(defun mark-end-of-sentence (arg)
  "Put mark at end of sentence.  Arg works as in `forward-sentence'."
  (interactive "p")
  (push-mark
    (save-excursion
      (forward-sentence arg)
      (point))
    nil t))

(defun transpose-sentences (arg)
  "Interchange this (next) and previous sentence."
  (interactive "*p")
  (transpose-subr 'forward-sentence arg))

;;; paragraphs.el ends here
Commit	Line	Data
6594deb0 ER	1	;;; paragraphs.el --- paragraph and sentence parsing.
6594deb0 ER	2
9750e079 ER	3	;; Copyright (C) 1985, 86, 87, 1991 Free Software Foundation, Inc.
9750e079 ER	4
4821e2af	5	;; Maintainer: FSF
d7b4d18f	6	;; Keywords: wp
4821e2af	7
a2535589 JA	8	;; This file is part of GNU Emacs.
	9
	10	;; GNU Emacs is free software; you can redistribute it and/or modify
	11	;; it under the terms of the GNU General Public License as published by
29add8b9	12	;; the Free Software Foundation; either version 2, or (at your option)
a2535589 JA	13	;; any later version.
	14
	15	;; GNU Emacs is distributed in the hope that it will be useful,
	16	;; but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	18	;; GNU General Public License for more details.
	19
	20	;; You should have received a copy of the GNU General Public License
	21	;; along with GNU Emacs; see the file COPYING. If not, write to
	22	;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
	23
edbd2f74 ER	24	;;; Commentary:
	25
	26	;; This package provides the paragraph-oriented commands documented in the
	27	;; Emacs manual.
	28
4821e2af	29	;;; Code:
a2535589	30
6503cec3 JB	31	(defconst paragraph-start "^[ \t\n\f]" "\
	32	*Regexp for beginning of a line that starts OR separates paragraphs.")
	33
6503cec3 JB	34	(defconst paragraph-separate "^[ \t\f]*$" "\
	35	*Regexp for beginning of a line that separates paragraphs.
	36	If you change this, you may have to change paragraph-start also.")
	37
6503cec3 JB	38	(defconst sentence-end (purecopy "[.?!][]\"')}]\\($\\\| $\\\|\t\\\| \\)[ \t\n]") "\
6503cec3 JB	39	*Regexp describing the end of a sentence.
51534471 JB	40	All paragraph boundaries also end sentences, regardless.
	41
	42	In order to be recognized as the end of a sentence, the ending period,
	43	question mark, or exclamation point must be followed by two spaces,
	44	unless it's inside some sort of quotes or parenthesis.")
6503cec3	45
6503cec3 JB	46	(defconst page-delimiter "^\014" "\
	47	*Regexp describing line-beginnings that separate pages.")
	48
6503cec3 JB	49	(defvar paragraph-ignore-fill-prefix nil "\
	50	Non-nil means the paragraph commands are not affected by `fill-prefix'.
	51	This is desirable in modes where blank lines are the paragraph delimiters.")
77176e73	52
a2535589 JA	53
	54	(defun forward-paragraph (&optional arg)
	55	"Move forward to end of paragraph.
	56	With arg N, do it N times; negative arg -N means move forward N paragraphs.
	57
	58	A line which `paragraph-start' matches either separates paragraphs
	59	\(if `paragraph-separate' matches it also) or is the first line of a paragraph.
	60	A paragraph end is the beginning of a line which is not part of the paragraph
	61	to which the end of the previous line belongs, or the end of the buffer."
	62	(interactive "p")
	63	(or arg (setq arg 1))
	64	(let* ((fill-prefix-regexp
	65	(and fill-prefix (not (equal fill-prefix ""))
	66	(not paragraph-ignore-fill-prefix)
	67	(regexp-quote fill-prefix)))
	68	(paragraph-separate
	69	(if fill-prefix-regexp
	70	(concat paragraph-separate "\\\|^"
	71	fill-prefix-regexp "[ \t]*$")
	72	paragraph-separate)))
	73	(while (< arg 0)
	74	(if (and (not (looking-at paragraph-separate))
	75	(re-search-backward "^\n" (max (1- (point)) (point-min)) t))
	76	nil
	77	(forward-char -1) (beginning-of-line)
	78	(while (and (not (bobp)) (looking-at paragraph-separate))
	79	(forward-line -1))
	80	(end-of-line)
	81	;; Search back for line that starts or separates paragraphs.
	82	(if (if fill-prefix-regexp
	83	;; There is a fill prefix; it overrides paragraph-start.
	84	(progn
	85	(while (progn (beginning-of-line)
	86	(and (not (bobp))
	87	(not (looking-at paragraph-separate))
	88	(looking-at fill-prefix-regexp)))
	89	(forward-line -1))
	90	(not (bobp)))
	91	(re-search-backward paragraph-start nil t))
	92	;; Found one.
	93	(progn
	94	(while (and (not (eobp)) (looking-at paragraph-separate))
	95	(forward-line 1))
	96	(if (eq (char-after (- (point) 2)) ?\n)
	97	(forward-line -1)))
	98	;; No starter or separator line => use buffer beg.
	99	(goto-char (point-min))))
	100	(setq arg (1+ arg)))
	101	(while (> arg 0)
	102	(beginning-of-line)
	103	(while (prog1 (and (not (eobp))
	104	(looking-at paragraph-separate))
	105	(forward-line 1)))
	106	(if fill-prefix-regexp
	107	;; There is a fill prefix; it overrides paragraph-start.
	108	(while (and (not (eobp))
	109	(not (looking-at paragraph-separate))
	110	(looking-at fill-prefix-regexp))
	111	(forward-line 1))
	112	(if (re-search-forward paragraph-start nil t)
	113	(goto-char (match-beginning 0))
	114	(goto-char (point-max))))
	115	(setq arg (1- arg)))))
	116
117	(defun backward-paragraph (&optional arg)
118	"Move backward to start of paragraph.
119	With arg N, do it N times; negative arg -N means move forward N paragraphs.
120
23b34992 BP	121	A paragraph start is the beginning of a line which is a
	122	`first-line-of-paragraph' or which is ordinary text and follows a
	123	paragraph-separating line; except: if the first real line of a
	124	paragraph is preceded by a blank line, the paragraph starts at that
	125	blank line.
	126
	127	See `forward-paragraph' for more information."
a2535589 JA	128	(interactive "p")
	129	(or arg (setq arg 1))
	130	(forward-paragraph (- arg)))
	131
	132	(defun mark-paragraph ()
	133	"Put point at beginning of this paragraph, mark at end.
	134	The paragraph marked is the one that contains point or follows point."
	135	(interactive)
	136	(forward-paragraph 1)
0b108c01	137	(push-mark nil t t)
a2535589 JA	138	(backward-paragraph 1))
	139
	140	(defun kill-paragraph (arg)
	141	"Kill forward to end of paragraph.
	142	With arg N, kill forward to Nth end of paragraph;
	143	negative arg -N means kill backward to Nth start of paragraph."
23b34992	144	(interactive "p")
2247b0fc	145	(kill-region (point) (save-excursion (forward-paragraph arg) (point))))
a2535589 JA	146
	147	(defun backward-kill-paragraph (arg)
	148	"Kill back to start of paragraph.
	149	With arg N, kill back to Nth start of paragraph;
	150	negative arg -N means kill forward to Nth end of paragraph."
23b34992	151	(interactive "p")
2247b0fc	152	(kill-region (point) (save-excursion (backward-paragraph arg) (point))))
a2535589 JA	153
	154	(defun transpose-paragraphs (arg)
	155	"Interchange this (or next) paragraph with previous one."
	156	(interactive "*p")
	157	(transpose-subr 'forward-paragraph arg))
	158
	159	(defun start-of-paragraph-text ()
	160	(let ((opoint (point)) npoint)
	161	(forward-paragraph -1)
	162	(setq npoint (point))
	163	(skip-chars-forward " \t\n")
b4e6c391 RS	164	;; If the range of blank lines found spans the original start point,
	165	;; try again from the beginning of it.
	166	;; Must be careful to avoid infinite loop
	167	;; when following a single return at start of buffer.
	168	(if (and (>= (point) opoint) (< npoint opoint))
a2535589 JA	169	(progn
	170	(goto-char npoint)
	171	(if (> npoint (point-min))
	172	(start-of-paragraph-text))))))
	173
	174	(defun end-of-paragraph-text ()
	175	(let ((opoint (point)))
	176	(forward-paragraph 1)
	177	(if (eq (preceding-char) ?\n) (forward-char -1))
	178	(if (<= (point) opoint)
	179	(progn
	180	(forward-char 1)
	181	(if (< (point) (point-max))
	182	(end-of-paragraph-text))))))
	183
	184	(defun forward-sentence (&optional arg)
51534471	185	"Move forward to next `sentence-end'. With argument, repeat.
23b34992	186	With negative argument, move backward repeatedly to `sentence-beginning'.
a2535589	187
23b34992 BP	188	The variable `sentence-end' is a regular expression that matches ends of
23b34992 BP	189	sentences. Also, every paragraph boundary terminates sentences as well."
a2535589 JA	190	(interactive "p")
	191	(or arg (setq arg 1))
	192	(while (< arg 0)
	193	(let ((par-beg (save-excursion (start-of-paragraph-text) (point))))
	194	(if (re-search-backward (concat sentence-end "[^ \t\n]") par-beg t)
	195	(goto-char (1- (match-end 0)))
	196	(goto-char par-beg)))
	197	(setq arg (1+ arg)))
	198	(while (> arg 0)
	199	(let ((par-end (save-excursion (end-of-paragraph-text) (point))))
	200	(if (re-search-forward sentence-end par-end t)
	201	(skip-chars-backward " \t\n")
	202	(goto-char par-end)))
	203	(setq arg (1- arg))))
	204
	205	(defun backward-sentence (&optional arg)
	206	"Move backward to start of sentence. With arg, do it arg times.
23b34992	207	See `forward-sentence' for more information."
a2535589 JA	208	(interactive "p")
	209	(or arg (setq arg 1))
	210	(forward-sentence (- arg)))
	211
	212	(defun kill-sentence (&optional arg)
	213	"Kill from point to end of sentence.
	214	With arg, repeat; negative arg -N means kill back to Nth start of sentence."
	215	(interactive "*p")
2247b0fc	216	(kill-region (point) (save-excursion (forward-sentence arg) (point))))
a2535589 JA	217
	218	(defun backward-kill-sentence (&optional arg)
	219	"Kill back from point to start of sentence.
	220	With arg, repeat, or kill forward to Nth end of sentence if negative arg -N."
	221	(interactive "*p")
7270bdb0	222	(kill-region (point) (save-excursion (backward-sentence arg) (point))))
a2535589 JA	223
a2535589 JA	224	(defun mark-end-of-sentence (arg)
23b34992	225	"Put mark at end of sentence. Arg works as in `forward-sentence'."
a2535589 JA	226	(interactive "p")
	227	(push-mark
	228	(save-excursion
	229	(forward-sentence arg)
a524dc5b RS	230	(point))
a524dc5b RS	231	nil t))
a2535589 JA	232
	233	(defun transpose-sentences (arg)
	234	"Interchange this (next) and previous sentence."
	235	(interactive "*p")
	236	(transpose-subr 'forward-sentence arg))
6594deb0 ER	237
6594deb0 ER	238	;;; paragraphs.el ends here