1;;; paragraphs.el --- paragraph and sentence parsing. 2 3;; Copyright (C) 1985, 86, 87, 91, 94 Free Software Foundation, Inc. 4 5;; Maintainer: FSF 6;; Keywords: wp 7 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 12;; the Free Software Foundation; either version 2, or (at your option) 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 24;;; Commentary: 25 26;; This package provides the paragraph-oriented commands documented in the 27;; Emacs manual. 28 29;;; Code: 30 31(defconst paragraph-start "^[ \t\n\f]" "\ 32*Regexp for beginning of a line that starts OR separates paragraphs. 33This regexp should match lines that separate paragraphs 34and should also match lines that start a paragraph 35\(and are part of that paragraph). 36The variable `paragraph-separate' specifies how to distinguish 37lines that start paragraphs from lines that separate them.") 38 39(defconst paragraph-separate "^[ \t\f]*$" "\ 40*Regexp for beginning of a line that separates paragraphs. 41If you change this, you may have to change paragraph-start also.") 42 43(defconst sentence-end (purecopy "[.?!][]\"')}]*\\($\\| $\\|\t\\| \\)[ \t\n]*") "\ 44*Regexp describing the end of a sentence. 45All paragraph boundaries also end sentences, regardless. 46 47In order to be recognized as the end of a sentence, the ending period, 48question mark, or exclamation point must be followed by two spaces, 49unless it's inside some sort of quotes or parenthesis.") 50 51(defconst page-delimiter "^\014" "\ 52*Regexp describing line-beginnings that separate pages.") 53 54(defvar paragraph-ignore-fill-prefix nil "\ 55Non-nil means the paragraph commands are not affected by `fill-prefix'. 56This is desirable in modes where blank lines are the paragraph delimiters.") 57 58 59(defun forward-paragraph (&optional arg) 60 "Move forward to end of paragraph. 61With arg N, do it N times; negative arg -N means move backward N paragraphs. 62 63A line which `paragraph-start' matches either separates paragraphs 64\(if `paragraph-separate' matches it also) or is the first line of a paragraph. 65A paragraph end is the beginning of a line which is not part of the paragraph 66to which the end of the previous line belongs, or the end of the buffer." 67 (interactive "p") 68 (or arg (setq arg 1)) 69 (let* ((fill-prefix-regexp 70 (and fill-prefix (not (equal fill-prefix "")) 71 (not paragraph-ignore-fill-prefix) 72 (regexp-quote fill-prefix))) 73 (paragraph-separate 74 (if fill-prefix-regexp 75 (concat paragraph-separate "\\|^" 76 fill-prefix-regexp "[ \t]*$") 77 paragraph-separate))) 78 (while (and (< arg 0) (not (bobp))) 79 (if (and (not (looking-at paragraph-separate)) 80 (re-search-backward "^\n" (max (1- (point)) (point-min)) t)) 81 nil 82 ;; Move back over paragraph-separating lines. 83 (forward-char -1) (beginning-of-line) 84 (while (and (not (bobp)) (looking-at paragraph-separate)) 85 (forward-line -1)) 86 (if (bobp) 87 nil 88 ;; Go to end of the previous (non-separating) line. 89 (end-of-line) 90 ;; Search back for line that starts or separates paragraphs. 91 (if (if fill-prefix-regexp 92 ;; There is a fill prefix; it overrides paragraph-start. 93 (progn 94 (while (progn (beginning-of-line) 95 (and (not (bobp)) 96 (not (looking-at paragraph-separate)) 97 (looking-at fill-prefix-regexp))) 98 (forward-line -1)) 99 (not (bobp))) 100 (re-search-backward paragraph-start nil t)) 101 ;; Found one. 102 (progn 103 ;; Move forward over paragraph separators. 104 ;; We know this cannot reach the place we started 105 ;; because we know we moved back over a non-separator. 106 (while (and (not (eobp)) (looking-at paragraph-separate)) 107 (forward-line 1)) 108 (if (eq (char-after (- (point) 2)) ?\n) 109 (forward-line -1))) 110 ;; No starter or separator line => use buffer beg. 111 (goto-char (point-min))))) 112 (setq arg (1+ arg))) 113 (while (and (> arg 0) (not (eobp))) 114 (beginning-of-line) 115 (while (prog1 (and (not (eobp)) 116 (looking-at paragraph-separate)) 117 (forward-line 1))) 118 (if fill-prefix-regexp 119 ;; There is a fill prefix; it overrides paragraph-start. 120 (while (and (not (eobp)) 121 (not (looking-at paragraph-separate)) 122 (looking-at fill-prefix-regexp)) 123 (forward-line 1)) 124 (if (re-search-forward paragraph-start nil t) 125 (goto-char (match-beginning 0)) 126 (goto-char (point-max)))) 127 (setq arg (1- arg))))) 128 129(defun backward-paragraph (&optional arg) 130 "Move backward to start of paragraph. 131With arg N, do it N times; negative arg -N means move forward N paragraphs. 132 133A paragraph start is the beginning of a line which is a 134`first-line-of-paragraph' or which is ordinary text and follows a 135paragraph-separating line; except: if the first real line of a 136paragraph is preceded by a blank line, the paragraph starts at that 137blank line. 138 139See `forward-paragraph' for more information." 140 (interactive "p") 141 (or arg (setq arg 1)) 142 (forward-paragraph (- arg))) 143 144(defun mark-paragraph () 145 "Put point at beginning of this paragraph, mark at end. 146The paragraph marked is the one that contains point or follows point." 147 (interactive) 148 (forward-paragraph 1) 149 (push-mark nil t t) 150 (backward-paragraph 1)) 151 152(defun kill-paragraph (arg) 153 "Kill forward to end of paragraph. 154With arg N, kill forward to Nth end of paragraph; 155negative arg -N means kill backward to Nth start of paragraph." 156 (interactive "p") 157 (kill-region (point) (progn (forward-paragraph arg) (point)))) 158 159(defun backward-kill-paragraph (arg) 160 "Kill back to start of paragraph. 161With arg N, kill back to Nth start of paragraph; 162negative arg -N means kill forward to Nth end of paragraph." 163 (interactive "p") 164 (kill-region (point) (progn (backward-paragraph arg) (point)))) 165 166(defun transpose-paragraphs (arg) 167 "Interchange this (or next) paragraph with previous one." 168 (interactive "*p") 169 (transpose-subr 'forward-paragraph arg)) 170 171(defun start-of-paragraph-text () 172 (let ((opoint (point)) npoint) 173 (forward-paragraph -1) 174 (setq npoint (point)) 175 (skip-chars-forward " \t\n") 176 ;; If the range of blank lines found spans the original start point, 177 ;; try again from the beginning of it. 178 ;; Must be careful to avoid infinite loop 179 ;; when following a single return at start of buffer. 180 (if (and (>= (point) opoint) (< npoint opoint)) 181 (progn 182 (goto-char npoint) 183 (if (> npoint (point-min)) 184 (start-of-paragraph-text)))))) 185 186(defun end-of-paragraph-text () 187 (let ((opoint (point))) 188 (forward-paragraph 1) 189 (if (eq (preceding-char) ?\n) (forward-char -1)) 190 (if (<= (point) opoint) 191 (progn 192 (forward-char 1) 193 (if (< (point) (point-max)) 194 (end-of-paragraph-text)))))) 195 196(defun forward-sentence (&optional arg) 197 "Move forward to next `sentence-end'. With argument, repeat. 198With negative argument, move backward repeatedly to `sentence-beginning'. 199 200The variable `sentence-end' is a regular expression that matches ends of 201sentences. Also, every paragraph boundary terminates sentences as well." 202 (interactive "p") 203 (or arg (setq arg 1)) 204 (while (< arg 0) 205 (let ((par-beg (save-excursion (start-of-paragraph-text) (point)))) 206 (if (re-search-backward (concat sentence-end "[^ \t\n]") par-beg t) 207 (goto-char (1- (match-end 0))) 208 (goto-char par-beg))) 209 (setq arg (1+ arg))) 210 (while (> arg 0) 211 (let ((par-end (save-excursion (end-of-paragraph-text) (point)))) 212 (if (re-search-forward sentence-end par-end t) 213 (skip-chars-backward " \t\n") 214 (goto-char par-end))) 215 (setq arg (1- arg)))) 216 217(defun backward-sentence (&optional arg) 218 "Move backward to start of sentence. With arg, do it arg times. 219See `forward-sentence' for more information." 220 (interactive "p") 221 (or arg (setq arg 1)) 222 (forward-sentence (- arg))) 223 224(defun kill-sentence (&optional arg) 225 "Kill from point to end of sentence. 226With arg, repeat; negative arg -N means kill back to Nth start of sentence." 227 (interactive "*p") 228 (kill-region (point) (progn (forward-sentence arg) (point)))) 229 230(defun backward-kill-sentence (&optional arg) 231 "Kill back from point to start of sentence. 232With arg, repeat, or kill forward to Nth end of sentence if negative arg -N." 233 (interactive "*p") 234 (kill-region (point) (progn (backward-sentence arg) (point)))) 235 236(defun mark-end-of-sentence (arg) 237 "Put mark at end of sentence. Arg works as in `forward-sentence'." 238 (interactive "p") 239 (push-mark 240 (save-excursion 241 (forward-sentence arg) 242 (point)) 243 nil t)) 244 245(defun transpose-sentences (arg) 246 "Interchange this (next) and previous sentence." 247 (interactive "*p") 248 (transpose-subr 'forward-sentence arg)) 249 250;;; paragraphs.el ends here 251