-;; View: Peruse file or buffer without editing.
-;; Copyright (C) 1985, 1989 Free Software Foundation, Inc.
-;; Principal author K. Shane Hartman
+;;; view.el --- peruse file or buffer without editing
+
+;; Copyright (C) 1985, 1989, 1994, 1995, 1997, 2000, 2001, 2002,
+;; 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
+
+;; Author: K. Shane Hartman
+;; Maintainer: Inge Frick <inge@nada.kth.se>
+;; Keywords: files
;; 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)
+;; 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,
;; 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.
+;; 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 provides the `view' minor mode documented in the Emacs
+;; user's manual.
+;; View mode entry and exit is done through the functions view-mode-enter
+;; and view-mode-exit. Use these functions to enter or exit view-mode from
+;; emacs lisp programs.
+;; We use both view- and View- as prefix for symbols. View- is used as
+;; prefix for commands that have a key binding. view- is used for commands
+;; without key binding. The purpose of this is to make it easier for a
+;; user to use command name completion.
+
+;;; Suggested key bindings:
+;;
+;; (define-key ctl-x-4-map "v" 'view-file-other-window) ; ^x4v
+;; (define-key ctl-x-5-map "v" 'view-file-other-frame) ; ^x5v
+;;
+;; You could also bind view-file, view-buffer, view-buffer-other-window and
+;; view-buffer-other-frame to keys.
+\f
+;;; Code:
+
+(defgroup view nil
+ "Peruse file or buffer without editing."
+ :link '(function-link view-mode)
+ :link '(custom-manual "(emacs)Misc File Ops")
+ :group 'wp
+ :group 'editing)
+
+(defcustom view-highlight-face 'highlight
+ "*The face used for highlighting the match found by View mode search."
+ :type 'face
+ :group 'view)
+
+;; `view-mode-auto-exit' is replaced by the following option variable which
+;; only says if scrolling past buffer end should leave view mode or not, it
+;; doesn't say if leaving view mode should restore windows or not. The latter
+;; is now controlled by the presence of a value in `view-return-to-alist'.
+(defcustom view-scroll-auto-exit nil
+ "*Non-nil means scrolling past the end of buffer exits View mode.
+nil means attempting to scroll past the end of the buffer,
+only rings the bell and gives a message on how to leave."
+ :type 'boolean
+ :group 'view)
+
+(defcustom view-try-extend-at-buffer-end nil
+ "*Non-nil means try load more of file when reaching end of buffer.
+This variable is mainly intended to be temporarily set to non-nil by
+the F command in view-mode, but you can set it to t if you want the action
+for all scroll commands in view mode."
+ :type 'boolean
+ :group 'view)
+
+(defcustom view-remove-frame-by-deleting nil
+ "*Determine how View mode removes a frame no longer needed.
+If nil, make an icon of the frame. If non-nil, delete the frame."
+ :type 'boolean
+ :group 'view)
+
+(defcustom view-exits-all-viewing-windows nil
+ "*Non-nil means restore all windows used to view buffer.
+Commands that restore windows when finished viewing a buffer, apply to all
+windows that display the buffer and have restore information in
+`view-return-to-alist'.
+If `view-exits-all-viewing-windows' is nil, only the selected window is
+considered for restoring."
+ :type 'boolean
+ :group 'view)
+
+(defcustom view-inhibit-help-message nil
+ "*Non-nil inhibits the help message showed upon entering View mode."
+ :type 'boolean
+ :group 'view
+ :version "22.1")
+;;;###autoload
+(defvar view-mode nil
+ "Non-nil if View mode is enabled.
+Don't change this variable directly, you must change it by one of the
+functions that enable or disable view mode.")
+;;;###autoload
+(make-variable-buffer-local 'view-mode)
+
+(defcustom view-mode-hook nil
+ "Normal hook run when starting to view a buffer or file."
+ :type 'hook
+ :group 'view)
+\f
+(defvar view-old-buffer-read-only nil)
+(make-variable-buffer-local 'view-old-buffer-read-only)
+
+(defvar view-old-Helper-return-blurb)
+(make-variable-buffer-local 'view-old-Helper-return-blurb)
+
+;; Just to avoid warnings.
+(defvar Helper-return-blurb)
+
+(defvar view-page-size nil
+ "Default number of lines to scroll by View page commands.
+If nil that means use the window size.")
+(make-variable-buffer-local 'view-page-size)
+
+(defvar view-half-page-size nil
+ "Default number of lines to scroll by View half page commands.
+If nil that means use half the window size.")
+(make-variable-buffer-local 'view-half-page-size)
+
+(defvar view-last-regexp nil)
+(make-variable-buffer-local 'view-last-regexp) ; Global is better???
+
+(defvar view-return-to-alist nil
+ "What to do with used windows and where to go when finished viewing buffer.
+This is local in each buffer being viewed.
+It is added to by `view-mode-enter' when starting to view a buffer and
+subtracted from by `view-mode-exit' when finished viewing the buffer.
+
+See RETURN-TO-ALIST argument of function `view-mode-exit' for the format of
+`view-return-to-alist'.")
+(make-variable-buffer-local 'view-return-to-alist)
+(put 'view-return-to-alist 'permanent-local t)
+
+(defvar view-exit-action nil
+ "nil or a function with one argument (a buffer) called when finished viewing.
+This is local in each buffer being viewed.
+The \\[view-file] and \\[view-file-other-window] commands may set this to
+`kill-buffer'.")
+(make-variable-buffer-local 'view-exit-action)
+
+(defvar view-no-disable-on-exit nil
+ "If non-nil, View mode \"exit\" commands don't actually disable View mode.
+Instead, these commands just switch buffers or windows.
+This is set in certain buffers by specialized features such as help commands
+that use View mode automatically.")
+
+(defvar view-overlay nil
+ "Overlay used to display where a search operation found its match.
+This is local in each buffer, once it is used.")
+(make-variable-buffer-local 'view-overlay)
+
+(unless (assq 'view-mode minor-mode-alist)
+ (setq minor-mode-alist
+ (cons (list 'view-mode
+ (propertize " View"
+ 'local-map mode-line-minor-mode-keymap
+ 'help-echo "mouse-3: minor mode menu"))
+ minor-mode-alist)))
+\f
+;; Define keymap inside defvar to make it easier to load changes.
+;; Some redundant "less"-like key bindings below have been commented out.
+(defvar view-mode-map
+ (let ((map (make-sparse-keymap)))
+ (define-key map "C" 'View-kill-and-leave)
+ (define-key map "c" 'View-leave)
+ (define-key map "Q" 'View-quit-all)
+ (define-key map "E" 'View-exit-and-edit)
+; (define-key map "v" 'View-exit)
+ (define-key map "e" 'View-exit)
+ (define-key map "q" 'View-quit)
+; (define-key map "N" 'View-search-last-regexp-backward)
+ (define-key map "p" 'View-search-last-regexp-backward)
+ (define-key map "n" 'View-search-last-regexp-forward)
+; (define-key map "?" 'View-search-regexp-backward) ; Less does this.
+ (define-key map "\\" 'View-search-regexp-backward)
+ (define-key map "/" 'View-search-regexp-forward)
+ (define-key map "r" 'isearch-backward)
+ (define-key map "s" 'isearch-forward)
+ (define-key map "m" 'point-to-register)
+ (define-key map "'" 'register-to-point)
+ (define-key map "x" 'exchange-point-and-mark)
+ (define-key map "@" 'View-back-to-mark)
+ (define-key map "." 'set-mark-command)
+ (define-key map "%" 'View-goto-percent)
+; (define-key map "G" 'View-goto-line-last)
+ (define-key map "g" 'View-goto-line)
+ (define-key map "=" 'what-line)
+ (define-key map "F" 'View-revert-buffer-scroll-page-forward)
+; (define-key map "k" 'View-scroll-line-backward)
+ (define-key map "y" 'View-scroll-line-backward)
+; (define-key map "j" 'View-scroll-line-forward)
+ (define-key map "\n" 'View-scroll-line-forward)
+ (define-key map "\r" 'View-scroll-line-forward)
+ (define-key map "u" 'View-scroll-half-page-backward)
+ (define-key map "d" 'View-scroll-half-page-forward)
+ (define-key map "z" 'View-scroll-page-forward-set-page-size)
+ (define-key map "w" 'View-scroll-page-backward-set-page-size)
+; (define-key map "b" 'View-scroll-page-backward)
+ (define-key map "\C-?" 'View-scroll-page-backward)
+; (define-key map "f" 'View-scroll-page-forward)
+ (define-key map " " 'View-scroll-page-forward)
+ (define-key map "o" 'View-scroll-to-buffer-end)
+ (define-key map ">" 'end-of-buffer)
+ (define-key map "<" 'beginning-of-buffer)
+ (define-key map "-" 'negative-argument)
+ (define-key map "9" 'digit-argument)
+ (define-key map "8" 'digit-argument)
+ (define-key map "7" 'digit-argument)
+ (define-key map "6" 'digit-argument)
+ (define-key map "5" 'digit-argument)
+ (define-key map "4" 'digit-argument)
+ (define-key map "3" 'digit-argument)
+ (define-key map "2" 'digit-argument)
+ (define-key map "1" 'digit-argument)
+ (define-key map "0" 'digit-argument)
+ (define-key map "H" 'describe-mode)
+ (define-key map "?" 'describe-mode) ; Maybe do as less instead? See above.
+ (define-key map "h" 'describe-mode)
+ map))
+
+(or (assq 'view-mode minor-mode-map-alist)
+ (setq minor-mode-map-alist
+ (cons (cons 'view-mode view-mode-map) minor-mode-map-alist)))
+\f
+;;; Commands that enter or exit view mode.
-(provide 'view)
+;;;###autoload
+(defun view-file (file)
+ "View FILE in View mode, returning to previous buffer when done.
+Emacs commands editing the buffer contents are not available; instead,
+a special set of commands (mostly letters and punctuation)
+are defined for moving around in the buffer.
+Space scrolls forward, Delete scrolls backward.
+For list of all View commands, type H or h while viewing.
-(defvar view-mode-map nil)
-(if view-mode-map
- nil
- (setq view-mode-map (make-keymap))
- (fillarray view-mode-map 'View-undefined)
- (define-key view-mode-map "\C-c" 'view-exit)
- (define-key view-mode-map "\C-z" 'suspend-emacs)
- (define-key view-mode-map "q" 'view-exit)
- (define-key view-mode-map "-" 'negative-argument)
- (define-key view-mode-map "0" 'digit-argument)
- (define-key view-mode-map "1" 'digit-argument)
- (define-key view-mode-map "2" 'digit-argument)
- (define-key view-mode-map "3" 'digit-argument)
- (define-key view-mode-map "4" 'digit-argument)
- (define-key view-mode-map "5" 'digit-argument)
- (define-key view-mode-map "6" 'digit-argument)
- (define-key view-mode-map "7" 'digit-argument)
- (define-key view-mode-map "8" 'digit-argument)
- (define-key view-mode-map "9" 'digit-argument)
- (define-key view-mode-map "\C-u" 'universal-argument)
- (define-key view-mode-map "\e" nil)
- (define-key view-mode-map "\C-x" 'Control-X-prefix)
- (define-key view-mode-map "\e-" 'negative-argument)
- (define-key view-mode-map "\e0" 'digit-argument)
- (define-key view-mode-map "\e1" 'digit-argument)
- (define-key view-mode-map "\e2" 'digit-argument)
- (define-key view-mode-map "\e3" 'digit-argument)
- (define-key view-mode-map "\e4" 'digit-argument)
- (define-key view-mode-map "\e5" 'digit-argument)
- (define-key view-mode-map "\e6" 'digit-argument)
- (define-key view-mode-map "\e7" 'digit-argument)
- (define-key view-mode-map "\e8" 'digit-argument)
- (define-key view-mode-map "\e9" 'digit-argument)
- (define-key view-mode-map "<" 'beginning-of-buffer)
- (define-key view-mode-map ">" 'end-of-buffer)
- (define-key view-mode-map "\ev" 'View-scroll-lines-backward)
- (define-key view-mode-map "\C-v" 'View-scroll-lines-forward)
- (define-key view-mode-map " " 'View-scroll-lines-forward)
- (define-key view-mode-map "\177" 'View-scroll-lines-backward)
- (define-key view-mode-map "\n" 'View-scroll-one-more-line)
- (define-key view-mode-map "\r" 'View-scroll-one-more-line)
- (define-key view-mode-map "\C-l" 'recenter)
- (define-key view-mode-map "z" 'View-scroll-lines-forward-set-scroll-size)
- (define-key view-mode-map "g" 'View-goto-line)
- (define-key view-mode-map "=" 'what-line)
- (define-key view-mode-map "." 'set-mark-command)
- (define-key view-mode-map "\C-@" 'set-mark-command)
- (define-key view-mode-map "'" 'View-back-to-mark)
- (define-key view-mode-map "@" 'View-back-to-mark)
- (define-key view-mode-map "x" 'exchange-point-and-mark)
- (define-key view-mode-map "h" 'Helper-describe-bindings)
- (define-key view-mode-map "?" 'Helper-describe-bindings)
- (define-key view-mode-map "\C-h" 'Helper-help)
- (define-key view-mode-map "\C-n" 'next-line)
- (define-key view-mode-map "\C-p" 'previous-line)
- (define-key view-mode-map "\C-s" 'isearch-forward)
- (define-key view-mode-map "\C-r" 'isearch-backward)
- (define-key view-mode-map "s" 'isearch-forward)
- (define-key view-mode-map "r" 'isearch-backward)
- (define-key view-mode-map "/" 'View-search-regexp-forward)
- (define-key view-mode-map "\\" 'View-search-regexp-backward)
- ;; This conflicts with the standard binding of isearch-regexp-forward
- (define-key view-mode-map "\e\C-s" 'View-search-regexp-forward)
- (define-key view-mode-map "\e\C-r" 'View-search-regexp-backward)
- (define-key view-mode-map "n" 'View-search-last-regexp-forward)
- (define-key view-mode-map "p" 'View-search-last-regexp-backward)
- )
+This command runs the normal hook `view-mode-hook'."
+ (interactive "fView file: ")
+ (unless (file-exists-p file) (error "%s does not exist" file))
+ (let ((had-a-buf (get-file-buffer file))
+ (buffer (find-file-noselect file)))
+ (if (eq (with-current-buffer buffer
+ (get major-mode 'mode-class))
+ 'special)
+ (progn
+ (switch-to-buffer buffer)
+ (message "Not using View mode because the major mode is special"))
+ (view-buffer buffer (and (not had-a-buf) 'kill-buffer)))))
+
+;;;###autoload
+(defun view-file-other-window (file)
+ "View FILE in View mode in another window.
+Return that window to its previous buffer when done.
+Emacs commands editing the buffer contents are not available; instead,
+a special set of commands (mostly letters and punctuation)
+are defined for moving around in the buffer.
+Space scrolls forward, Delete scrolls backward.
+For list of all View commands, type H or h while viewing.
+This command runs the normal hook `view-mode-hook'."
+ (interactive "fIn other window view file: ")
+ (unless (file-exists-p file) (error "%s does not exist" file))
+ (let ((had-a-buf (get-file-buffer file)))
+ (view-buffer-other-window (find-file-noselect file) nil
+ (and (not had-a-buf) 'kill-buffer))))
;;;###autoload
-(defun view-file (file-name)
- "View FILE in View mode, returning to previous buffer when done.
-The usual Emacs commands are not available; instead,
+(defun view-file-other-frame (file)
+ "View FILE in View mode in another frame.
+Maybe delete other frame and/or return to previous buffer when done.
+Emacs commands editing the buffer contents are not available; instead,
a special set of commands (mostly letters and punctuation)
are defined for moving around in the buffer.
Space scrolls forward, Delete scrolls backward.
-For list of all View commands, type ? or h while viewing.
+For list of all View commands, type H or h while viewing.
+
+This command runs the normal hook `view-mode-hook'."
+ (interactive "fIn other frame view file: ")
+ (unless (file-exists-p file) (error "%s does not exist" file))
+ (let ((had-a-buf (get-file-buffer file)))
+ (view-buffer-other-frame (find-file-noselect file) nil
+ (and (not had-a-buf) 'kill-buffer))))
-Calls the value of view-hook if that is non-nil."
- (interactive "fView file: ")
- (let ((old-buf (current-buffer))
- (had-a-buf (get-file-buffer file-name))
- (buf-to-view (find-file-noselect file-name)))
- (switch-to-buffer buf-to-view t)
- (view-mode old-buf
- (and (not had-a-buf) (not (buffer-modified-p buf-to-view))
- 'kill-buffer))))
;;;###autoload
-(defun view-buffer (buffer-name)
+(defun view-buffer (buffer &optional exit-action)
"View BUFFER in View mode, returning to previous buffer when done.
-The usual Emacs commands are not available; instead,
+Emacs commands editing the buffer contents are not available; instead,
a special set of commands (mostly letters and punctuation)
are defined for moving around in the buffer.
Space scrolls forward, Delete scrolls backward.
-For list of all View commands, type ? or h while viewing.
+For list of all View commands, type H or h while viewing.
+
+This command runs the normal hook `view-mode-hook'.
+
+Optional argument EXIT-ACTION is either nil or a function with buffer as
+argument. This function is called when finished viewing buffer.
+Use this argument instead of explicitly setting `view-exit-action'."
-Calls the value of view-hook if that is non-nil."
(interactive "bView buffer: ")
- (let ((old-buf (current-buffer)))
- (switch-to-buffer buffer-name t)
- (view-mode old-buf nil)))
+ (let ((undo-window (list (window-buffer) (window-start) (window-point))))
+ (switch-to-buffer buffer)
+ (view-mode-enter (cons (selected-window) (cons nil undo-window))
+ exit-action)))
;;;###autoload
-(defun view-mode (&optional prev-buffer action)
- "Major mode for viewing text but not editing it.
-Letters do not insert themselves. Instead these commands are provided.
-Most commands take prefix arguments. Commands dealing with lines
-default to \"scroll size\" lines (initially size of window).
-Search commands default to a repeat count of one.
-M-< or < move to beginning of buffer.
-M-> or > move to end of buffer.
-C-v or Space scroll forward lines.
-M-v or DEL scroll backward lines.
-CR or LF scroll forward one line (backward with prefix argument).
-z like Space except set number of lines for further
- scrolling commands to scroll by.
-C-u and Digits provide prefix arguments. `-' denotes negative argument.
-= prints the current line number.
-g goes to line given by prefix argument.
-/ or M-C-s searches forward for regular expression
-\\ or M-C-r searches backward for regular expression.
-n searches forward for last regular expression.
-p searches backward for last regular expression.
-C-@ or . set the mark.
-x exchanges point and mark.
-C-s or s do forward incremental search.
-C-r or r do reverse incremental search.
-@ or ' return to mark and pops mark ring.
- Mark ring is pushed at start of every
- successful search and when jump to line to occurs.
- The mark is set on jump to buffer start or end.
-? or h provide help message (list of commands).
-C-h provides help (list of commands or description of a command).
-C-n moves down lines vertically.
-C-p moves upward lines vertically.
-C-l recenters the screen.
-q or C-c exit view-mode and return to previous buffer.
-
-Entry to this mode calls the value of view-hook if non-nil.
-\\{view-mode-map}"
-; Not interactive because dangerous things happen
-; if you call it without passing a buffer as argument
-; and they are not easy to fix.
-; (interactive)
- (make-local-variable 'view-old-mode-line-buffer-identification)
- (setq view-old-mode-line-buffer-identification
- mode-line-buffer-identification)
- (make-local-variable 'view-old-buffer-read-only)
- (setq view-old-buffer-read-only buffer-read-only)
- (make-local-variable 'view-old-mode-name)
- (setq view-old-mode-name mode-name)
- (make-local-variable 'view-old-major-mode)
- (setq view-old-major-mode major-mode)
- (make-local-variable 'view-old-local-map)
- (setq view-old-local-map (current-local-map))
- (make-local-variable 'view-old-Helper-return-blurb)
- (setq view-old-Helper-return-blurb
- (and (boundp 'Helper-return-blurb) Helper-return-blurb))
-
- (setq buffer-read-only t)
- (setq mode-line-buffer-identification
- (list
- (if (buffer-file-name)
- "Viewing %f"
- "Viewing %b")))
- (setq mode-name "View")
- (setq major-mode 'view-mode)
- (setq Helper-return-blurb
+(defun view-buffer-other-window (buffer &optional not-return exit-action)
+ "View BUFFER in View mode in another window.
+Return to previous buffer when done, unless optional NOT-RETURN is non-nil.
+Emacs commands editing the buffer contents are not available; instead,
+a special set of commands (mostly letters and punctuation)
+are defined for moving around in the buffer.
+Space scrolls forward, Delete scrolls backward.
+For list of all View commands, type H or h while viewing.
+
+This command runs the normal hook `view-mode-hook'.
+
+Optional argument EXIT-ACTION is either nil or a function with buffer as
+argument. This function is called when finished viewing buffer.
+Use this argument instead of explicitly setting `view-exit-action'."
+ (interactive "bIn other window view buffer:\nP")
+ (let* ((win ; This window will be selected by
+ (get-lru-window)) ; switch-to-buffer-other-window below.
+ (return-to
+ (and (not not-return)
+ (cons (selected-window)
+ (if (eq win (selected-window))
+ t ; Has to make new window.
+ (list
+ (window-buffer win) ; Other windows old buffer.
+ (window-start win)
+ (window-point win)))))))
+ (switch-to-buffer-other-window buffer)
+ (view-mode-enter (and return-to (cons (selected-window) return-to))
+ exit-action)))
+
+;;;###autoload
+(defun view-buffer-other-frame (buffer &optional not-return exit-action)
+ "View BUFFER in View mode in another frame.
+Return to previous buffer when done, unless optional NOT-RETURN is non-nil.
+Emacs commands editing the buffer contents are not available; instead,
+a special set of commands (mostly letters and punctuation)
+are defined for moving around in the buffer.
+Space scrolls forward, Delete scrolls backward.
+For list of all View commands, type H or h while viewing.
+
+This command runs the normal hook `view-mode-hook'.
+
+Optional argument EXIT-ACTION is either nil or a function with buffer as
+argument. This function is called when finished viewing buffer.
+Use this argument instead of explicitly setting `view-exit-action'."
+ (interactive "bView buffer in other frame: \nP")
+ (let ((return-to
+ (and (not not-return) (cons (selected-window) t)))) ; Old window.
+ (switch-to-buffer-other-frame buffer)
+ (view-mode-enter (and return-to (cons (selected-window) return-to))
+ exit-action)))
+\f
+;;;###autoload
+(defun view-mode (&optional arg)
+ ;; In the following documentation string we have to use some explicit key
+ ;; bindings instead of using the \\[] construction. The reason for this
+ ;; is that most commands have more than one key binding.
+ "Toggle View mode, a minor mode for viewing text but not editing it.
+With ARG, turn View mode on iff ARG is positive.
+
+Emacs commands that do not change the buffer contents are available as usual.
+Kill commands insert text in kill buffers but do not delete. Other commands
+\(among them most letters and punctuation) beep and tell that the buffer is
+read-only.
+\\<view-mode-map>
+The following additional commands are provided. Most commands take prefix
+arguments. Page commands default to \"page size\" lines which is almost a whole
+window full, or number of lines set by \\[View-scroll-page-forward-set-page-size] or \\[View-scroll-page-backward-set-page-size]. Half page commands default to
+and set \"half page size\" lines which initially is half a window full. Search
+commands default to a repeat count of one.
+
+H, h, ? This message.
+Digits provide prefix arguments.
+\\[negative-argument] negative prefix argument.
+\\[beginning-of-buffer] move to the beginning of buffer.
+> move to the end of buffer.
+\\[View-scroll-to-buffer-end] scroll so that buffer end is at last line of window.
+SPC scroll forward \"page size\" lines.
+ With prefix scroll forward prefix lines.
+DEL scroll backward \"page size\" lines.
+ With prefix scroll backward prefix lines.
+\\[View-scroll-page-forward-set-page-size] like \\[View-scroll-page-forward] but with prefix sets \"page size\" to prefix.
+\\[View-scroll-page-backward-set-page-size] like \\[View-scroll-page-backward] but with prefix sets \"page size\" to prefix.
+\\[View-scroll-half-page-forward] scroll forward \"half page size\" lines. With prefix, sets
+ \"half page size\" to prefix lines and scrolls forward that much.
+\\[View-scroll-half-page-backward] scroll backward \"half page size\" lines. With prefix, sets
+ \"half page size\" to prefix lines and scrolls backward that much.
+RET, LFD scroll forward one line. With prefix scroll forward prefix line(s).
+y scroll backward one line. With prefix scroll backward prefix line(s).
+\\[View-revert-buffer-scroll-page-forward] revert-buffer if necessary and scroll forward.
+ Use this to view a changing file.
+\\[what-line] prints the current line number.
+\\[View-goto-percent] goes prefix argument (default 100) percent into buffer.
+\\[View-goto-line] goes to line given by prefix argument (default first line).
+. set the mark.
+x exchanges point and mark.
+\\[View-back-to-mark] return to mark and pops mark ring.
+ Mark ring is pushed at start of every successful search and when
+ jump to line occurs. The mark is set on jump to buffer start or end.
+\\[point-to-register] save current position in character register.
+' go to position saved in character register.
+s do forward incremental search.
+r do reverse incremental search.
+\\[View-search-regexp-forward] searches forward for regular expression, starting after current page.
+ ! and @ have a special meaning at the beginning of the regexp.
+ ! means search for a line with no match for regexp. @ means start
+ search at beginning (end for backward search) of buffer.
+\\ searches backward for regular expression, starting before current page.
+\\[View-search-last-regexp-forward] searches forward for last regular expression.
+p searches backward for last regular expression.
+\\[View-quit] quit View mode, restoring this window and buffer to previous state.
+ \\[View-quit] is the normal way to leave view mode.
+\\[View-exit] exit View mode but stay in current buffer. Use this if you started
+ viewing a buffer (file) and find out you want to edit it.
+ This command restores the previous read-only status of the buffer.
+\\[View-exit-and-edit] exit View mode, and make the current buffer editable
+ even if it was not editable before entry to View mode.
+\\[View-quit-all] quit View mode, restoring all windows to previous state.
+\\[View-leave] quit View mode and maybe switch buffers, but don't kill this buffer.
+\\[View-kill-and-leave] quit View mode, kill current buffer and go back to other buffer.
+
+The effect of \\[View-leave] , \\[View-quit] and \\[View-kill-and-leave] depends on how view-mode was entered. If it was
+entered by view-file, view-file-other-window, view-file-other-frame, or
+\\[dired-view-file] \(\\[view-file], \\[view-file-other-window],
+\\[view-file-other-frame], or the Dired mode v command),
+then \\[View-quit] will try to kill the current buffer.
+If view-mode was entered from another buffer, by \\[view-buffer],
+\\[view-buffer-other-window], \\[view-buffer-other frame], \\[view-file],
+\\[view-file-other-window], or \\[view-file-other-frame],
+then \\[View-leave] , \\[View-quit] and \\[View-kill-and-leave] will return to that buffer.
+
+Entry to view-mode runs the normal hook `view-mode-hook'."
+ (interactive "P")
+ (unless (and arg ; Do nothing if already OK.
+ (if (> (prefix-numeric-value arg) 0) view-mode (not view-mode)))
+ (if view-mode (view-mode-disable)
+ (view-mode-enable))))
+\f
+(defun view-mode-enable ()
+ "Turn on View mode."
+ ;; Always leave view mode before changing major mode.
+ ;; This is to guarantee that the buffer-read-only variable is restored.
+ (add-hook 'change-major-mode-hook 'view-mode-disable nil t)
+ (setq view-mode t
+ view-page-size nil
+ view-half-page-size nil
+ view-old-buffer-read-only buffer-read-only
+ buffer-read-only t
+ view-old-Helper-return-blurb (and (boundp 'Helper-return-blurb)
+ Helper-return-blurb)
+ Helper-return-blurb
(format "continue viewing %s"
(if (buffer-file-name)
(file-name-nondirectory (buffer-file-name))
- (buffer-name))))
-
- (make-local-variable 'view-exit-action)
- (setq view-exit-action action)
- (make-local-variable 'view-prev-buffer)
- (setq view-prev-buffer prev-buffer)
- (make-local-variable 'view-exit-position)
- (setq view-exit-position (point-marker))
-
- (make-local-variable 'view-scroll-size)
- (setq view-scroll-size nil)
- (make-local-variable 'view-last-regexp)
- (setq view-last-regexp nil)
-
- (beginning-of-line)
- (setq goal-column nil)
-
- (use-local-map view-mode-map)
- (run-hooks 'view-hook)
- (view-helpful-message))
-
-(defun view-exit ()
- "Exit from view-mode.
-If you viewed an existing buffer, that buffer returns to its previous mode.
-If you viewed a file that was not present in Emacs, its buffer is killed."
+ (buffer-name))))
+ (force-mode-line-update)
+ (run-hooks 'view-mode-hook))
+
+(defun view-mode-disable ()
+ "Turn off View mode."
+ (remove-hook 'change-major-mode-hook 'view-mode-disable t)
+ (and view-overlay (delete-overlay view-overlay))
+ (force-mode-line-update)
+ ;; Calling toggle-read-only while View mode is enabled
+ ;; sets view-read-only to t as a buffer-local variable
+ ;; after exiting View mode. That arranges that the next toggle-read-only
+ ;; will reenable View mode.
+ ;; Cancelling View mode in any other way should cancel that, too,
+ ;; so that View mode stays off if toggle-read-only is called.
+ (if (local-variable-p 'view-read-only)
+ (kill-local-variable 'view-read-only))
+ (setq view-mode nil
+ Helper-return-blurb view-old-Helper-return-blurb)
+ (if buffer-read-only
+ (setq buffer-read-only view-old-buffer-read-only)))
+
+;;;###autoload
+(defun view-mode-enter (&optional return-to exit-action) "\
+Enter View mode and set up exit from view mode depending on optional arguments.
+If RETURN-TO is non-nil it is added as an element to the buffer local alist
+`view-return-to-alist'.
+Save EXIT-ACTION in buffer local variable `view-exit-action'.
+It should be either nil or a function that takes a buffer as argument.
+This function will be called by `view-mode-exit'.
+
+RETURN-TO is either nil, meaning do nothing when exiting view mode, or
+it has the format (WINDOW OLD-WINDOW . OLD-BUF-INFO).
+WINDOW is a window used for viewing.
+OLD-WINDOW is nil or the window to select after viewing.
+OLD-BUF-INFO tells what to do with WINDOW when exiting. It is one of:
+1) nil Do nothing.
+2) t Delete WINDOW or, if it is the only window, its frame.
+3) (OLD-BUFF START POINT) Display buffer OLD-BUFF with displayed text
+ starting at START and point at POINT in WINDOW.
+4) quit-window Do `quit-window' in WINDOW.
+
+For list of all View commands, type H or h while viewing.
+
+This function runs the normal hook `view-mode-hook'."
+ (if return-to
+ (let ((entry (assq (car return-to) view-return-to-alist)))
+ (if entry (setcdr entry (cdr return-to))
+ (setq view-return-to-alist (cons return-to view-return-to-alist)))))
+ (if exit-action (setq view-exit-action exit-action))
+ (unless view-mode ; Do nothing if already in view mode.
+ (view-mode-enable)
+ (force-mode-line-update)
+ (unless view-inhibit-help-message
+ (message "%s"
+ (substitute-command-keys "\
+View mode: type \\[help-command] for help, \\[describe-mode] for commands, \\[View-quit] to quit.")))))
+\f
+(defun view-mode-exit (&optional return-to-alist exit-action all-win)
+ "Exit View mode in various ways, depending on optional arguments.
+RETURN-TO-ALIST, EXIT-ACTION and ALL-WIN determine what to do after exit.
+EXIT-ACTION is nil or a function that is called with current buffer as
+argument.
+RETURN-TO-ALIST is an alist that for some of the windows displaying the
+current buffer, associate information on what to do with those windows.
+If ALL-WIN or the variable `view-exits-all-viewing-windows' is non-nil,
+then all windows on RETURN-TO-ALIST are restored to their old state.
+Otherwise only the selected window is affected (if it is on RETURN-TO-ALIST).
+
+Elements of RETURN-TO-ALIST have the format (WINDOW OLD-WINDOW . OLD-BUF-INFO).
+WINDOW is a window displaying the current buffer.
+OLD-WINDOW is nil or a window to select after viewing.
+OLD-BUF-INFO is information on what to do with WINDOW and is one of:
+1) nil Do nothing.
+2) t Delete WINDOW and, if it is the only window, its frame.
+3) (OLD-BUF START POINT) Display buffer OLD-BUF with displayed text
+ starting at START and point at POINT in WINDOW.
+4) quit-window Do `quit-window' in WINDOW.
+
+If one of the WINDOW in RETURN-TO-ALIST is the selected window and the
+corresponding OLD-WINDOW is a live window, then select OLD-WINDOW."
+ (setq all-win
+ (and return-to-alist (or all-win view-exits-all-viewing-windows)))
+ (if view-mode ; Only do something if in view mode.
+ (let* ((buffer (current-buffer))
+ window notlost
+ (sel-old (assq (selected-window) return-to-alist))
+ (alist (cond
+ (all-win ; Try to restore all windows.
+ (append return-to-alist nil)) ; Copy.
+ (sel-old ; Only selected window.
+ (list sel-old))))
+ (old-window (if sel-old (car (cdr sel-old)))))
+ (if all-win ; Follow chains of old-windows.
+ (let ((c (length alist)) a)
+ (while (and (> c 0) ; Safety if mutually refering windows.
+ (or (not (window-live-p old-window))
+ (eq buffer (window-buffer old-window)))
+ (setq a (assq old-window alist)))
+ (setq c (1- c))
+ (setq old-window (car (cdr a))))
+ (if (or (zerop c) (not (window-live-p old-window)))
+ (setq old-window (selected-window)))))
+ (or view-no-disable-on-exit
+ (view-mode-disable))
+ (while alist ; Restore windows with info.
+ (setq notlost nil)
+ (if (and (window-live-p (setq window (car (car alist))))
+ (eq buffer (window-buffer window)))
+ (let ((frame (window-frame window))
+ (old-buf-info (cdr (cdr (car alist)))))
+ (if all-win (select-window window))
+ (cond
+ ((and (consp old-buf-info) ; Case 3.
+ (buffer-live-p (car old-buf-info)))
+ (set-window-buffer window (car old-buf-info)) ; old-buf
+ (set-window-start window (car (cdr old-buf-info)))
+ (set-window-point window (car (cdr (cdr old-buf-info)))))
+ ((eq old-buf-info 'quit-window)
+ (quit-window)) ; Case 4.
+ ((not (eq old-buf-info t)) nil) ; Not case 2, do nothing.
+ ((not (one-window-p t)) (delete-window))
+ ((not (eq frame (next-frame)))
+ ;; Not the only frame, so can safely be removed.
+ (if view-remove-frame-by-deleting
+ (delete-frame frame)
+ (setq notlost t) ; Keep the window. See below.
+ (iconify-frame frame))))))
+ ;; If a frame is removed by iconifying it, then the window is not
+ ;; really lost. In this case we keep the entry in
+ ;; view-return-to-alist so that if the user deiconifies the frame
+ ;; and then press q, then the frame is iconified again.
+ (unless notlost
+ (setq view-return-to-alist
+ (delete (car alist) view-return-to-alist)))
+ (setq alist (cdr alist)))
+ (if (window-live-p old-window) ; still existing window
+ (select-window old-window))
+ (when exit-action
+ (setq view-exit-action nil)
+ (funcall exit-action buffer))
+ (force-mode-line-update))))
+\f
+(defun View-exit ()
+ "Exit View mode but stay in current buffer."
+ (interactive)
+ (view-mode-exit))
+
+;;;###autoload
+(defun View-exit-and-edit ()
+ "Exit View mode and make the current buffer editable."
(interactive)
- (setq mode-line-buffer-identification
- view-old-mode-line-buffer-identification)
- (setq major-mode view-old-major-mode)
- (setq mode-name view-old-mode-name)
- (use-local-map (current-local-map))
- (setq buffer-read-only view-old-buffer-read-only)
-
- (goto-char view-exit-position)
- (set-marker view-exit-position nil)
-
- ;; Now do something to the buffer that we were viewing
- ;; (such as kill it).
- (let ((viewed-buffer (current-buffer))
- (action view-exit-action))
- (switch-to-buffer view-prev-buffer)
- (if action (funcall action viewed-buffer))))
-
-(defun view-helpful-message ()
- (message
- (if (and (eq (key-binding "\C-h") 'Helper-help)
- (eq (key-binding "?") 'Helper-describe-bindings)
- (eq (key-binding "\C-c") 'view-exit))
- "Type C-h for help, ? for commands, C-c to quit"
- (substitute-command-keys
- "Type \\[Helper-help] for help, \\[Helper-describe-bindings] for commands, \\[exit-recursive-edit] to quit."))))
-
-(defun View-undefined ()
+ (let ((view-old-buffer-read-only nil)
+ (view-no-disable-on-exit nil))
+ (view-mode-exit)))
+
+(defun View-leave ()
+ "Quit View mode and maybe switch buffers, but don't kill this buffer."
(interactive)
- (ding)
- (view-helpful-message))
+ (view-mode-exit view-return-to-alist))
-(defun view-window-size () (1- (window-height)))
+(defun View-quit ()
+ "Quit View mode, trying to restore window and buffer to previous state.
+Maybe kill this buffer. Try to restore selected window to previous state
+and go to previous buffer or window."
+ (interactive)
+ (view-mode-exit view-return-to-alist view-exit-action))
-(defun view-scroll-size ()
- (min (view-window-size) (or view-scroll-size (view-window-size))))
+(defun View-quit-all ()
+ "Quit View mode, trying to restore windows and buffers to previous state.
+Maybe kill current buffer. Try to restore all windows viewing buffer to
+previous state and go to previous buffer or window."
+ (interactive)
+ (view-mode-exit view-return-to-alist view-exit-action t))
-(defvar view-hook nil
- "If non-nil, its value is called when viewing buffer or file.")
+(defun View-kill-and-leave ()
+ "Quit View mode, kill current buffer and return to previous buffer."
+ (interactive)
+ (view-mode-exit view-return-to-alist (or view-exit-action 'kill-buffer) t))
+\f
+
+;;; Some help routines.
+
+(defun view-window-size ()
+ ;; Window height excluding mode line.
+ (1- (window-height)))
;(defun view-last-command (&optional who what)
; (setq view-last-command-entry this-command)
; (funcall view-last-command view-last-command-argument))
; (setq this-command view-last-command-entry))
+(defun view-recenter ()
+ ;; Center point in window.
+ (recenter (/ (view-window-size) 2)))
+
+(defun view-page-size-default (lines)
+ ;; Get page size.
+ (let ((default (- (view-window-size) next-screen-context-lines)))
+ (if (or (null lines) (zerop (setq lines (prefix-numeric-value lines))))
+ default
+ (min (abs lines) default))))
+
+(defun view-set-half-page-size-default (lines)
+ ;; Get and maybe set half page size.
+ (if (not lines) (or view-half-page-size
+ (/ (view-window-size) 2))
+ (setq view-half-page-size
+ (if (zerop (setq lines (prefix-numeric-value lines)))
+ (/ (view-window-size) 2)
+ (view-page-size-default lines)))))
+
+
+;;; Commands for moving around in the buffer.
+
+(defun View-goto-percent (&optional percent)
+ "Move to end (or prefix PERCENT) of buffer in View mode.
+Display is centered at point.
+Also set the mark at the position where point was."
+ (interactive "P")
+ (push-mark)
+ (goto-char
+ (if percent
+ (+ (point-min)
+ (floor (* (- (point-max) (point-min)) 0.01
+ (max 0 (min 100 (prefix-numeric-value percent))))))
+ (point-max)))
+ (view-recenter))
+
+;(defun View-goto-line-last (&optional line)
+;"Move to last (or prefix LINE) line in View mode.
+;Display is centered at LINE.
+;Sets mark at starting position and pushes mark ring."
+; (interactive "P")
+; (push-mark)
+; (if line (goto-line (prefix-numeric-value line))
+; (goto-char (point-max))
+; (beginning-of-line))
+; (view-recenter))
+
(defun View-goto-line (&optional line)
- "Move to LINE in View mode.
-Display is centered at LINE. Sets mark at starting position and pushes
-mark ring."
+ "Move to first (or prefix LINE) line in View mode.
+Display is centered at LINE.
+Also set the mark at the position where point was."
(interactive "p")
(push-mark)
- (goto-line (or line 1))
- (recenter (/ (view-window-size) 2)))
+ (goto-line line)
+ (view-recenter))
-(defun View-scroll-lines-forward (&optional lines)
- "Scroll forward in View mode, or exit if end of text is visible.
-No arg means whole window full, or number of lines set by \\[View-scroll-lines-forward-set-scroll-size].
-Arg is number of lines to scroll."
+(defun View-back-to-mark (&optional ignore)
+ "Return to last mark set in View mode, else beginning of file.
+Display that line at the center of the window.
+This command pops the mark ring, so that successive
+invocations return to earlier marks."
+ (interactive)
+ (goto-char (or (mark t) (point-min)))
+ (pop-mark)
+ (view-recenter))
+\f
+(defun view-scroll-lines (lines backward default maxdefault)
+ ;; This function does the job for all the scrolling commands.
+ ;; Scroll forward LINES lines. If BACKWARD is true scroll backwards.
+ ;; If LINES is negative scroll in the other direction. If LINES is 0 or nil,
+ ;; scroll DEFAULT lines. If MAXDEFAULT is true then scroll no more than a
+ ;; window full.
+ (if (or (null lines) (zerop (setq lines (prefix-numeric-value lines))))
+ (setq lines default))
+ (when (< lines 0)
+ (setq backward (not backward)) (setq lines (- lines)))
+ (setq default (view-page-size-default nil)) ; Max scrolled at a time.
+ (if maxdefault (setq lines (min lines default)))
+ (cond
+ (backward (scroll-down lines))
+ ((view-really-at-end)
+ (if view-scroll-auto-exit (View-quit)
+ (ding)
+ (view-end-message)))
+ (t (while (> lines default)
+ (scroll-up default)
+ (setq lines (- lines default))
+ (if (view-really-at-end) (setq lines 0)))
+ (scroll-up lines)
+ (if (view-really-at-end) (view-end-message))
+ (move-to-window-line -1)
+ (beginning-of-line))))
+
+(defun view-really-at-end ()
+ ;; Return true if buffer end visible. Maybe revert buffer and test.
+ (and (pos-visible-in-window-p (point-max))
+ (let ((buf (current-buffer))
+ (bufname (buffer-name))
+ (file (buffer-file-name)))
+ (or (not view-try-extend-at-buffer-end)
+ (null file)
+ (verify-visited-file-modtime buf)
+ (not (file-exists-p file))
+ (when (buffer-modified-p buf)
+ (setq file (file-name-nondirectory file))
+ (not (yes-or-no-p
+ (format
+ "File %s changed on disk. Discard your edits%s? "
+ file
+ (if (string= bufname file) ""
+ (concat " in " bufname))))))
+ (progn
+ (revert-buffer t t t)
+ (pos-visible-in-window-p (point-max)))))))
+
+(defun view-end-message ()
+ ;; Tell that we are at end of buffer.
+ (goto-char (point-max))
+ (if view-return-to-alist
+ (message "End of buffer. Type %s to quit viewing."
+ (substitute-command-keys
+ (if view-scroll-auto-exit "\\[View-scroll-page-forward]"
+ "\\[View-quit]")))
+ (message "End of buffer")))
+\f
+(defun View-scroll-to-buffer-end ()
+ "Scroll backward or forward so that buffer end is at last line of window."
+ (interactive)
+ (let ((p (if (pos-visible-in-window-p (point-max)) (point))))
+ (goto-char (point-max))
+ (recenter -1)
+ (and p (goto-char p))))
+
+(defun View-scroll-page-forward (&optional lines)
+ "Scroll \"page size\" or prefix LINES lines forward in View mode.
+Exit if end of text is visible and `view-scroll-auto-exit' is non-nil.
+\"page size\" is whole window full, or number of lines set by
+\\[View-scroll-page-forward-set-page-size] or
+\\[View-scroll-page-backward-set-page-size].
+If LINES is more than a window-full, only the last window-full is shown."
+ (interactive "P")
+ (view-scroll-lines lines nil (view-page-size-default view-page-size) nil))
+
+(defun View-scroll-page-backward (&optional lines)
+ "Scroll \"page size\" or prefix LINES lines backward in View mode.
+See also `View-scroll-page-forward'."
(interactive "P")
- (if (pos-visible-in-window-p (point-max))
- (exit-recursive-edit))
- (setq lines
- (if lines (prefix-numeric-value lines)
- (view-scroll-size)))
-; (view-last-command 'View-scroll-lines-forward lines)
- (if (>= lines (view-window-size))
- (scroll-up nil)
- (if (>= (- lines) (view-window-size))
- (scroll-down nil)
- (scroll-up lines)))
- (cond ((pos-visible-in-window-p (point-max))
- (goto-char (point-max))
- (recenter -1)
- (message (substitute-command-keys
- "End. Type \\[exit-recursive-edit] to quit viewing."))))
- (move-to-window-line -1)
- (beginning-of-line))
-
-(defun View-scroll-lines-forward-set-scroll-size (&optional lines)
- "Scroll forward LINES lines in View mode, setting the \"scroll size\".
-This is the number of lines which \\[View-scroll-lines-forward] and \\[View-scroll-lines-backward] scroll by default.
-The absolute value of LINES is used, so this command can be used to scroll
-backwards (but \"scroll size\" is always positive). If LINES is greater than
-window height or omitted, then window height is assumed. If LINES is less
-than window height then scrolling context is provided from previous screen."
+ (view-scroll-lines lines t (view-page-size-default view-page-size) nil))
+
+(defun View-scroll-page-forward-set-page-size (&optional lines)
+ "Scroll forward LINES lines in View mode, setting the \"page size\".
+This is the number of lines which \\[View-scroll-page-forward] and
+\\[View-scroll-page-backward] scroll by default.
+If LINES is omitted or = 0, sets \"page size\" to window height and
+scrolls forward that much, otherwise scrolls forward LINES lines and sets
+\"page size\" to the minimum of window height and the absolute value of LINES.
+See also `View-scroll-page-forward'."
(interactive "P")
- (if (not lines)
- (setq view-scroll-size (view-window-size))
- (setq lines (prefix-numeric-value lines))
- (setq view-scroll-size
- (min (if (> lines 0) lines (- lines)) (view-window-size))))
- (View-scroll-lines-forward lines))
-
-(defun View-scroll-one-more-line (&optional arg)
- "Scroll one more line up in View mode.
-With ARG scroll one line down."
+ (view-scroll-lines lines nil
+ (setq view-page-size (view-page-size-default lines))
+ nil))
+
+(defun View-scroll-page-backward-set-page-size (&optional lines)
+ "Scroll backward prefix LINES lines in View mode, setting the \"page size\".
+See also `View-scroll-page-forward-set-page-size'."
+ (interactive "P")
+ (view-scroll-lines lines t
+ (setq view-page-size (view-page-size-default lines))
+ nil))
+
+(defun View-scroll-line-forward (&optional lines)
+ "Scroll forward one line (or prefix LINES lines) in View mode.
+See also `View-scroll-page-forward,' but note that scrolling is limited
+to minimum of LINES and one window-full."
(interactive "P")
- (View-scroll-lines-forward (if (not arg) 1 -1)))
+ (view-scroll-lines lines nil 1 t))
-(defun View-scroll-lines-backward (&optional lines)
- "Scroll backward in View mode.
-No arg means whole window full, or number of lines set by \\[View-scroll-lines-forward-set-scroll-size].
-Arg is number of lines to scroll."
+(defun View-scroll-line-backward (&optional lines)
+ "Scroll backward one line (or prefix LINES lines) in View mode.
+See also `View-scroll-line-forward'."
(interactive "P")
- (View-scroll-lines-forward (if lines
- (- (prefix-numeric-value lines))
- (- (view-scroll-size)))))
-
-(defun View-search-regexp-forward (times regexp)
- "Search forward for NTH occurrence of REGEXP in View mode.
-Displays line found at center of window. REGEXP is remembered for
-searching with \\[View-search-last-regexp-forward] and \\[View-search-last-regexp-backward]. Sets mark at starting position and pushes mark ring."
+ (view-scroll-lines lines t 1 t))
+
+(defun View-scroll-half-page-forward (&optional lines)
+ "Scroll forward a \"half page\" (or prefix LINES) lines in View mode.
+If LINES is not omitted, the \"half page size\" is set to the minimum of
+window height and the absolute value of LINES.
+LINES=0 resets \"half page size\" to half window height."
+ (interactive "P")
+ (view-scroll-lines lines nil (view-set-half-page-size-default lines) t))
+
+(defun View-scroll-half-page-backward (&optional lines)
+ "Scroll backward a \"half page\" (or prefix LINES) lines in View mode.
+See also `View-scroll-half-page-forward'."
+ (interactive "P")
+ (view-scroll-lines lines t (view-set-half-page-size-default lines) t))
+
+(defun View-revert-buffer-scroll-page-forward (&optional lines)
+ "Scroll forward, reverting buffer if needed, in View mode.
+If buffer has not been changed and the corresponding file is newer, first
+revert the buffer, then scroll.
+This command is useful if you are viewing a changing file.
+
+The prefix argument LINES says how many lines to scroll.
+If you don't specify a prefix argument, it uses the number of lines set by
+\\[View-scroll-page-forward-set-page-size] or
+\\[View-scroll-page-backward-set-page-size].
+If LINES is more than a window-full, only the last window-full is shown."
+ (interactive "P")
+ (let ((view-scroll-auto-exit nil)
+ (view-try-extend-at-buffer-end t))
+ (view-scroll-lines lines nil (view-page-size-default view-page-size) nil)))
+\f
+(defun View-search-regexp-forward (n regexp)
+ "Search forward for first (or prefix Nth) occurrence of REGEXP in View mode.
+
+Displays line found at center of window. Sets mark at starting position and
+pushes mark ring.
+
+Characters @ and ! are special at the beginning of REGEXP. They modify
+the search rather than become part of the pattern searched for.
+@ means search all the buffer i.e. start search at the beginning of buffer.
+! means search for a line that contains no match for the pattern.
+If REGEXP is empty or only consist of these control characters, then
+an earlier remembered REGEXP is used, otherwise REGEXP is remembered
+for use by later search commands.
+
+The variable `view-highlight-face' controls the face that is used
+for highlighting the match that is found."
(interactive "p\nsSearch forward (regexp): ")
- (if (> (length regexp) 0)
- (progn
- ;(view-last-command 'View-search-last-regexp-forward times)
- (view-search times regexp))))
-
-(defun View-search-regexp-backward (times regexp)
- "Search backward from window start for NTH instance of REGEXP in View mode.
-Displays line found at center of window. REGEXP is remembered for
-searching with \\[View-search-last-regexp-forward] and \\[View-search-last-regexp-backward]. Sets mark at starting position and pushes mark ring."
+ (view-search n regexp))
+
+(defun View-search-regexp-backward (n regexp)
+ "Search backward for first (or prefix Nth) occurrence of REGEXP in View mode.
+
+Displays line found at center of window. Sets mark at starting position and
+pushes mark ring.
+
+Characters @ and ! are special at the beginning of REGEXP. They modify
+the search rather than become part of the pattern searched for.
+@ means search all the buffer i.e. start search at the end of buffer.
+! means search for a line that contains no match for the pattern.
+If REGEXP is empty or only consist of these control characters, then
+an earlier remembered REGEXP is used, otherwise REGEXP is remembered
+for use by later search commands.
+
+The variable `view-highlight-face' controls the face that is used
+for highlighting the match that is found."
(interactive "p\nsSearch backward (regexp): ")
- (View-search-regexp-forward (- times) regexp))
+ (view-search (- n) regexp))
-(defun View-search-last-regexp-forward (times)
- "Search forward from window end for NTH instance of last regexp in View mode.
-Displays line found at center of window. Sets mark at starting position
-and pushes mark ring."
+(defun View-search-last-regexp-forward (n) "\
+Search forward for first (or prefix Nth) instance of last regexp in View mode.
+Displays line found at center of window. Sets mark at starting position and
+pushes mark ring.
+
+The variable `view-highlight-face' controls the face that is used
+for highlighting the match that is found."
(interactive "p")
- (View-search-regexp-forward times view-last-regexp))
+ (view-search n nil))
-(defun View-search-last-regexp-backward (times)
- "Search backward from window start for NTH instance of last regexp in View mode.
+(defun View-search-last-regexp-backward (n) "\
+Search backward for first (or prefix Nth) instance of last regexp in View mode.
Displays line found at center of window. Sets mark at starting position and
-pushes mark ring."
+pushes mark ring.
+
+The variable `view-highlight-face' controls the face that is used
+for highlighting the match that is found."
(interactive "p")
- (View-search-regexp-backward times view-last-regexp))
+ (view-search (- n) nil))
-(defun View-back-to-mark (&optional ignore)
- "Return to last mark set in View mode, else beginning of file.
-Displays line at center of window. Pops mark ring so successive
-invocations return to earlier marks."
- (interactive)
- (goto-char (or (mark) (point-min)))
- (pop-mark)
- (recenter (/ (view-window-size) 2)))
-
(defun view-search (times regexp)
- (setq view-last-regexp regexp)
- (let (where)
+ ;; This function does the job for all the View-search- commands.
+ ;; Search for the TIMESt match for REGEXP. If TIMES is negative
+ ;; search backwards. If REGEXP is nil use `view-last-regexp'.
+ ;; Charcters "!" and "@" have a special meaning at the beginning of
+ ;; REGEXP and are removed from REGEXP before the search "!" means
+ ;; search for lines with no match for REGEXP. "@" means search in
+ ;; the whole buffer, don't start searching from the present point.
+ (let (where no end ln)
+ (cond
+ ((and regexp (> (length regexp) 0)
+ (or (not (memq (string-to-char regexp) '(?! ?@)))
+ (progn
+ (if (member (substring regexp 0 2) '("!@" "@!"))
+ (setq end t no t ln 2)
+ (setq no (not (setq end (eq ?@ (string-to-char regexp))))
+ ln 1))
+ (> (length (setq regexp (substring regexp ln))) 0))))
+ (setq view-last-regexp (if no (list regexp) regexp)))
+ ((consp view-last-regexp)
+ (setq regexp (car view-last-regexp))
+ (unless (setq no (not no)) (setq view-last-regexp regexp)))
+ (view-last-regexp (setq regexp view-last-regexp)
+ (if no (setq view-last-regexp (list regexp))))
+ (t (error "No previous View-mode search")))
(save-excursion
- (move-to-window-line (if (< times 0) 0 -1))
- (if (re-search-forward regexp nil t times)
+ (if end (goto-char (if (< times 0) (point-max) (point-min)))
+ (move-to-window-line (if (< times 0) 0 -1)))
+ (if (if no (view-search-no-match-lines times regexp)
+ (re-search-forward regexp nil t times))
(setq where (point))))
(if where
(progn
(push-mark)
(goto-char where)
+ (if view-overlay
+ (move-overlay view-overlay (match-beginning 0) (match-end 0))
+ (setq view-overlay
+ (make-overlay (match-beginning 0) (match-end 0))))
+ (overlay-put view-overlay 'face view-highlight-face)
(beginning-of-line)
- (recenter (/ (view-window-size) 2)))
- (message "Can't find occurrence %d of %s" times regexp)
+ (view-recenter))
+ (message "Can't find occurrence %d of %s%s"
+ times (if no "no " "") regexp)
(sit-for 4))))
+(defun view-search-no-match-lines (times regexp)
+ ;; Search for the TIMESt occurrence of line with no match for REGEXP.
+ (let ((back (and (< times 0) (setq times (- times)) -1))
+ n)
+ (while (> times 0)
+ (save-excursion (beginning-of-line (if back (- times) (1+ times)))
+ (setq n (point)))
+ (setq times
+ (cond
+ ((< (count-lines (point) n) times) -1) ; Not enough lines.
+ ((or (null (re-search-forward regexp nil t back))
+ (if back (and (< (match-end 0) n)
+ (> (count-lines (match-end 0) n) 1))
+ (and (< n (match-beginning 0))
+ (> (count-lines n (match-beginning 0)) 1))))
+ 0) ; No match within lines.
+ (back (count-lines (max n (match-beginning 0)) (match-end 0)))
+ (t (count-lines (match-beginning 0) (min n (match-end 0))))))
+ (goto-char n))
+ (and (zerop times) (looking-at "^.*$"))))
+
+
+(provide 'view)
+
+;;; arch-tag: 6d0ace36-1d12-4de3-8de3-1fa3231636d7
+;;; view.el ends here