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Diffstat (limited to 'lisp/page.el')
| -rw-r--r-- | lisp/page.el | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/lisp/page.el b/lisp/page.el new file mode 100644 index 00000000000..19b29d02f08 --- /dev/null +++ b/lisp/page.el @@ -0,0 +1,123 @@ +;; Page motion commands for emacs. +;; Copyright (C) 1985 Free Software Foundation, Inc. + +;; 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 1, 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. + + +(defun forward-page (&optional count) + "Move forward to page boundary. With arg, repeat, or go back if negative. +A page boundary is any line whose beginning matches the regexp page-delimiter." + (interactive "p") + (or count (setq count 1)) + (while (and (> count 0) (not (eobp))) + (if (re-search-forward page-delimiter nil t) + nil + (goto-char (point-max))) + (setq count (1- count))) + (while (and (< count 0) (not (bobp))) + (forward-char -1) + (if (re-search-backward page-delimiter nil t) + (goto-char (match-end 0)) + (goto-char (point-min))) + (setq count (1+ count)))) + +(defun backward-page (&optional count) + "Move backward to page boundary. With arg, repeat, or go fwd if negative. +A page boundary is any line whose beginning matches the regexp page-delimiter." + (interactive "p") + (or count (setq count 1)) + (forward-page (- count))) + +(defun mark-page (&optional arg) + "Put mark at end of page, point at beginning. +A numeric arg specifies to move forward or backward by that many pages, +thus marking a page other than the one point was originally in." + (interactive "P") + (setq arg (if arg (prefix-numeric-value arg) 0)) + (if (> arg 0) + (forward-page arg) + (if (< arg 0) + (forward-page (1- arg)))) + (forward-page) + (push-mark nil t) + (forward-page -1)) + +(defun narrow-to-page (&optional arg) + "Make text outside current page invisible. +A numeric arg specifies to move forward or backward by that many pages, +thus showing a page other than the one point was originally in." + (interactive "P") + (setq arg (if arg (prefix-numeric-value arg) 0)) + (save-excursion + (widen) + (if (> arg 0) + (forward-page arg) + (if (< arg 0) + (forward-page (1- arg)))) + ;; Find the end of the page. + (forward-page) + ;; If we stopped due to end of buffer, stay there. + ;; If we stopped after a page delimiter, put end of restriction + ;; at the beginning of that line. + (if (save-excursion (beginning-of-line) + (looking-at page-delimiter)) + (beginning-of-line)) + (narrow-to-region (point) + (progn + ;; Find the top of the page. + (forward-page -1) + ;; If we found beginning of buffer, stay there. + ;; If extra text follows page delimiter on same line, + ;; include it. + ;; Otherwise, show text starting with following line. + (if (and (eolp) (not (bobp))) + (forward-line 1)) + (point))))) + +(defun count-lines-page () + "Report number of lines on current page, and how many are before or after point." + (interactive) + (save-excursion + (let ((opoint (point)) beg end + total before after) + (forward-page) + (beginning-of-line) + (or (looking-at page-delimiter) + (end-of-line)) + (setq end (point)) + (backward-page) + (setq beg (point)) + (setq total (count-lines beg end) + before (count-lines beg opoint) + after (count-lines opoint end)) + (message "Page has %d lines (%d + %d)" total before after)))) + +(defun what-page () + "Print page and line number of point." + (interactive) + (save-restriction + (widen) + (save-excursion + (beginning-of-line) + (let ((count 1) + (opoint (point))) + (goto-char 1) + (while (re-search-forward page-delimiter opoint t) + (setq count (1+ count))) + (message "Page %d, line %d" + count + (1+ (count-lines (point) opoint))))))) |