From 8846c425939694357d9b8e9f90250f9f6fc3f8c9 Mon Sep 17 00:00:00 2001 From: Eshel Yaron Date: Thu, 12 Jun 2025 17:29:17 +0200 Subject: [PATCH] Drop vcursor.el --- lisp/vcursor.el | 989 ------------------------------------------------ 1 file changed, 989 deletions(-) delete mode 100644 lisp/vcursor.el diff --git a/lisp/vcursor.el b/lisp/vcursor.el deleted file mode 100644 index b71c4207eb0..00000000000 --- a/lisp/vcursor.el +++ /dev/null @@ -1,989 +0,0 @@ -;;; vcursor.el --- manipulate an alternative ("virtual") cursor -*- lexical-binding: t; -*- - -;; Copyright (C) 1994-2025 Free Software Foundation, Inc. - -;; Author: Peter Stephenson -;; Maintainer: emacs-devel@gnu.org -;; Keywords: virtual cursor, convenience - -;; 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 3 of the License, 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. If not, see . - -;;; Commentary: - -;; Latest changes -;; ============== -;; -;; - *IMPORTANT* `vcursor-key-bindings' is now nil by default, to avoid -;; side-effects when the package is loaded. This means no keys are -;; bound by default. Use customize to change it to t to restore -;; the old behavior. (If you do it by hand in .emacs, it -;; must come before vcursor is loaded.) -;; - You can alter the main variables and the vcursor face via -;; M-x customize: go to the Editing group and find Vcursor. -;; - `vcursor-auto-disable' can now be 'copy (actually any value not nil -;; or t), which means that copying from the vcursor will be turned -;; off after any operation not involving the vcursor, but the -;; vcursor itself will be left alone. -;; - works on dumb terminals -;; - new keymap `vcursor-map' for binding to a prefix key -;; - `vcursor-compare-windows' substantially improved -;; - `vcursor-execute-{key,command}' much better about using the -;; right keymaps and arranging for the correct windows to be used -;; - `vcursor-window-funcall' can call functions interactively -;; - `vcursor-interpret-input' for special effects -;; -;; Introduction -;; ============ -;; -;; Virtual cursor commands. I got this idea from the old BBC micro. -;; You need a window system for the best effects. -;; -;; This is much easier to use than the instructions are to read. -;; First, you need to let vcursor define some keys: setting -;; vcursor-key-bindings to t before loading, or by customize, will -;; define various keys with the prefix C-S. You'll have to read -;; further if you don't want this. Then I suggest you simply load it -;; and play around with holding down Ctrl and Shift and pressing up, -;; down, left, right, tab, return, and see what happens. (Find a -;; scratch buffer before using C-S-tab: that toggles copying.) -;; -;; Most of the functions described in this documentation are in -;; parentheses so that if you have the package loaded you can type C-h -;; f on top of them for help. -;; -;; Using the cursor keys with both control and shift held down moves -;; around a virtual cursor, which is initially at point. When active, -;; it appears with an underline through it to distinguish it from the -;; normal cursor. You can then use one of the other commands to copy -;; characters from the location of the virtual cursor to point. This -;; is very useful, for example, when copying some previous text while -;; making changes to it at the same time, since you never have to move -;; the "real" cursor away from where you are inserting. -;; -;; The remaining default key bindings are based around the PC-type -;; cluster found above the cursor keys on a lot of keyboards, the -;; function keys which my limited knowledge of X terminals expects to -;; find at the top. Some functions are duplicated in more obvious -;; places for the X version. -;; -;; All the keybindings require you to hold down control and shift at -;; once. I assumed this combination wouldn't be heavily bound by most -;; people and that it would be easy to type with the left hand. -;; Inevitably it will clash with some other packages, but I can't help -;; that: an intuitive binding is a prerequisite here. See below for -;; other alternatives (search for "Oemacs"). There is also a keymap -;; which you can bind to a prefix key, which may give some more -;; intuitive alternatives in some cases, see `The vcursor keymap' below. -;; -;; Holding down control and shift and pressing insert (vcursor-copy) -;; copies one character from wherever the virtual cursor is to point; -;; point and the virtual cursor advance in the separate and equal -;; station to which... (etc.). M-C-S-return (vcursor-copy-line) -;; copies to the end of the line instead of just one character, -;; C-S-delete or C-S-remove (vcursor-copy-word) copies a word. -;; -;; A more general way of copying is to use C-S-tab, which is a toggle. -;; In the "on" state, moving the virtual cursor will copy the -;; moved-over text to the normal cursor position (including when going -;; backwards, though each piece of text moved over is copied forwards: -;; compare the behavior of C-S-up and C-S-left). -;; -;; However, that's just a small part of the magic. If the virtual -;; cursor goes off the display, it will be redisplayed in some other -;; window. (See the function (vcursor-find-window) for details of how -;; this window is chosen.) This gives you fingertip control over two -;; windows at once. -;; -;; C-S-return (vcursor-disable) disables the virtual cursor, removing -;; it so that it starts from point whenever you move it again --- note -;; that simply moving the cursor and virtual cursor on top of one -;; another does not have this effect. -;; -;; If you give C-S-return a positive prefix arg, it will also delete the -;; window (unless it's the current one). Whenever the virtual cursor -;; goes off-screen in its own window, point in that window is moved as -;; well to restore it to view. (It's easier that way, that's why. -;; However, point doesn't move unless the view in the window does, so -;; it's not tied to the virtual cursor location.) -;; -;; You can also use C-S-return with a negative prefix argument which -;; forces the vcursor to appear at point. This is particularly useful if -;; you actually want to edit in another window but would like to -;; remember the current cursor location for examining or copying from -;; that buffer. (I just hit C-S-right C-S-left, but I'm a hopeless -;; lowbrow.) -;; -;; There is also C-S-f6 (vcursor-other-window) which behaves like -;; C-x o on the virtual rather than the real cursor, except that it -;; will create another window if necessary. -;; -;; The keys C-S-prior (vcursor-scroll-down) and C-S-next -;; (vcursor-scroll-up) (i.e., PageUp and PageDown) will scroll the -;; virtual cursor window, appropriately chosen. They will always -;; create a new window or take over an old one if necessary. -;; Likewise, M-C-S-left and M-C-S-right move you to the -;; beginning or end of a line, C-S-home and C-S-end the -;; beginning or end of a buffer (these are also on M-C-S-up and -;; M-C-S-down for those of us stuck with DEC keyboards). -;; -;; C-S-f7 (vcursor-goto) will take you to the vcursor position -;; (swapping windows if it seems sensible) and (unless you give it a -;; prefix argument) delete the virtual cursor, so this is useful for -;; you to take over editing at the virtual cursor position. It is not -;; an error if the virtual cursor is not active; it simply leaves you -;; at point, because that is where the virtual cursor would start -;; from. -;; -;; In a similar vein, M-C-S-tab (hope your left hand's flexible; -;; C-S-select on DEC keyboards) (vcursor-swap-point) will take you to -;; the virtual cursor position but simultaneously put the virtual -;; cursor at the old cursor position. It is also supposed to ensure -;; that both are visible. -;; -;; C-S-f8 (C-S-find on DEC keyboards) (vcursor-isearch-forward) -;; allows you to do an isearch in another window. It works a bit like -;; vcursor-scroll-*; it moves into another window, calls isearch -;; there, and sets the virtual cursor position to the point found. In -;; other words, it works just like isearch but with the virtual cursor -;; instead of the real one (that's why it's called a "virtual -;; cursor"). While you are isearching, you are editing in the virtual -;; cursor window, but when you have finished you return to where you -;; started. Note that once you are in isearch all the keys are normal -;; --- use C-s, not C-S-f8, to search for the next occurrence. -;; -;; If you set the variable vcursor-auto-disable, then any command -;; which does not involve moving or copying from the virtual cursor -;; causes the virtual cursor to be disabled. If you set it to non-nil -;; but not t, then the vcursor itself will remain active, but copying -;; will be turned off, so that the next time the vcursor is moved no -;; text is copied over. Experience shows that this setting is -;; particularly useful. If you don't intend to use this, you can -;; comment out the `add-hook' line at the bottom of this file. (This -;; feature partially emulates the way the "copy" key on the BBC micro -;; worked; actually, the copy cursor was homed when you hit return. -;; This was in keeping with the line-by-line way of entering BASIC, -;; but is less appropriate here.) -;; -;; vcursor-compare-windows is now a reliable adaption of -;; compare-windows, which compares between point in the current buffer -;; and the vcursor location in the other one. It is an error if -;; vcursor is not set, however it will be brought up in another window -;; if it is not currently visible. The prefix argument acts just like -;; compare-windows, ignoring whitespace if set. (In versions before -;; 1.6, this simply called compare-windows, which was much less likely -;; to pick the two windows you wanted.) -;; -;; There is a way of moving the virtual cursor using ordinary -;; commands: C-S-f9 (vcursor-execute-key) reads a key string, -;; moves to the virtual cursor position, executes the command bound to -;; the string, then returns to the original point. Thus C-S-f9 M-m -;; moves the virtual cursor back to the first non-whitespace character -;; on its line. As the command is called interactively all the usual -;; ways of passing information to the command called, such as by a -;; prefix argument, are available. This has many uses not necessarily -;; related to moving the vcursor itself; it can do essentially -;; everything that the \C-x 4 series of commands can do and a lot -;; more. Note, however, that a new window is not used if the vcursor -;; is visible in the current one: this can lead to some strange effects, -;; but it is preferable to making a new window every time the vcursor -;; is moved in this may. -;; -;; C-S-f10 (C-S-x) (vcursor-execute-command) behaves the same way but -;; you enter the name of the command. To do anything really -;; complicated, you are better off using M-C-S-tab -;; (vcursor-swap-point), doing whatever it is, then calling M-C-S-tab -;; again. -;; -;; If you want to add your own moving or copying functions you should -;; be able to do this fairly easily with (vcursor-relative-move) and -;; (vcursor-copy) together with (vcursor-get-char-count). If you want to -;; do something in a different window, use (vcursor-window-funcall). -;; -;; Key bindings -;; ============ -;; -;; There is an alternative set of key bindings named "Oemacs" (for -;; historical reasons). This set uses separate control, shift and -;; meta keys with function keys 1 to 10. In particular, movement keys -;; are concentrated on f5 to f8 with (in increasing order of distance -;; traveled) C-, M- and S- as prefixes. See the actual bindings below -;; (search for C-f1). This is because the C-S- prefix is represented -;; by weird key sequences and the set is incomplete; if you don't mind -;; that, some hints are given in comments below. -;; -;; You can specify which set of key bindings to use by customizing the -;; user option `vcursor-key-bindings'. -;; -;; Usage on dumb terminals -;; ======================= -;; -;; If Emacs has set the variable window-system to nil, vcursor will -;; assume that overlays cannot be displayed in a different face, and -;; will instead use a string (the variable vcursor-string, by default "**>") -;; to show its position. Unlike the old-fashioned overlay arrow (as -;; used by debuggers), this appears between existing text, which can -;; make it hard to read if you're not used to it. (This seemed the -;; better option here.) This means moving the vcursor up and down is -;; a very efficient way of locating it! -;; -;; Everything else should function as expected, but there is no way to -;; get an easy key binding for the vcursor keys on a generic terminal. -;; Consequently a special keymap is defined for you to use traditional -;; methods: the keymap, however, is available on any terminal type. -;; -;; The vcursor keymap -;; ================== -;; -;; In addition to any other bindings, vcursor-map contains key definitions -;; for handling the vcursor. You should assign this to a prefix key -;; in the usual way, e.g. -;; (keymap-global-set "" vcursor-map) -;; and also as usual \C-h in this map will list the key definitions, which -;; are designed to be easy to remember. -;; -;; A special feature is provided by (vcursor-use-vcursor-map), bound -;; to t in that keymap. With this in effect, the main keymap -;; is overridden by the vcursor map, so keys like \C-p and so on -;; move the vcursor instead. Remember how to turn it off (type t), -;; or you are in serious trouble! Note that the cursor keys are not -;; bound by default in this keymap and will continue to move the -;; ordinary cursor. -;; -;; Interpreted input -;; ================= -;; -;; Just occasionally, you may want to pretend the strings copied from -;; the vcursor position are to be interpreted as if you had typed them -;; from the keyboard. Normally, they will just insert themselves anyway, -;; but in some modes (Info and calc for example) typing ordinary characters -;; does something else. To get this effect, set -;; vcursor-interpret-input to t. This is normally not a good idea as -;; interpreting input is very much slower than copying text. -;; -;; Un-features -;; =========== -;; -;; - The vcursor will not move to point-max, since otherwise it would -;; disappear. However, no error is flagged as point-max is a valid -;; point in the buffer. Thus cursor right or down at the second -;; last point in the file does not flag an error, which is inconsistent, -;; and if copying is on the last character (typically newline) will -;; be repeatedly copied. (I've tried making it flag an error -;; instead and that's worse since often the vcursor is sent to -;; point in some other window, which may be point-max.) -;; - The vcursor widens when over a tab character or right at the -;; end of the line. You're welcome to consider this a feature; -;; it's just a part of how overlays work. -;; - The vcursor obscures the real cursor. Creative use of overlays -;; could cure this. -;; - The vcursor does not remember its own previous positions. If -;; you cycle it back into a window it was in before, it will be at -;; point in that window. Often, that is where a previous recenter -;; left point, not where the vcursor was before. -;; (Note, however, that the vcursor does remember where it *is*, -;; even if it's off-screen. This can also lead to surprises, but I -;; don't think it's a bug.) -;; - vcursor-window-funcall could perhaps be smarter about restoring -;; the previous window state on failure. -;; - The logic in vcursor-find-window is rather complicated and -;; therefore bug-prone, though in practice it seems to work OK. -;; -;; Possible enhancements: -;; It would be easy to implement vcursor-push (save vcursor position -;; as mark and deactivate) and vcursor-pop (deactivate vcursor and -;; move to last pushed position) functions. - -;;; Code: - -(defgroup vcursor nil - "Manipulate an alternative (\"virtual\") cursor." - :prefix "vcursor-" - :group 'convenience) - -(defface vcursor - '((((class color)) (:foreground "blue" :background "cyan" :underline t)) - (t (:inverse-video t :underline t))) - "Face for the virtual cursor.") - -(defcustom vcursor-auto-disable nil - "If non-nil, disable the virtual cursor after use. -Any non-vcursor command will force `vcursor-disable' to be called. -If non-nil but not t, just make sure copying is toggled off, but don't -disable the vcursor." - :type '(choice (const t) (const nil) (const copy))) - -(defcustom vcursor-modifiers (list 'control 'shift) - "A list of modifiers that are used to define vcursor key bindings." - :type '(repeat symbol)) - -;; Needed for defcustom, must be up here -(defun vcursor-cs-binding (base &optional meta) - (vector (let ((key (append vcursor-modifiers (list (intern base))))) - (if meta - (cons 'meta key) - key)))) - -(defun vcursor-bind-keys (var value) - "Alter the value of the variable VAR to VALUE, binding keys as required. -VAR is usually `vcursor-key-bindings'. Normally this function is called -on loading vcursor and from the customize package." - (set var value) - (cond - ((not value)) ;; Don't set any key bindings. - ((eq value 'oemacs) - (global-set-key [C-f1] #'vcursor-toggle-copy) - (global-set-key [C-f2] #'vcursor-copy) - (global-set-key [C-f3] #'vcursor-copy-word) - (global-set-key [C-f4] #'vcursor-copy-line) - - (global-set-key [S-f1] #'vcursor-disable) - (global-set-key [S-f2] #'vcursor-other-window) - (global-set-key [S-f3] #'vcursor-goto) - (global-set-key [S-f4] #'vcursor-swap-point) - - (global-set-key [C-f5] #'vcursor-backward-char) - (global-set-key [C-f6] #'vcursor-previous-line) - (global-set-key [C-f7] #'vcursor-next-line) - (global-set-key [C-f8] #'vcursor-forward-char) - - (global-set-key [M-f5] #'vcursor-beginning-of-line) - (global-set-key [M-f6] #'vcursor-backward-word) - (global-set-key [M-f6] #'vcursor-forward-word) - (global-set-key [M-f8] #'vcursor-end-of-line) - - (global-set-key [S-f5] #'vcursor-beginning-of-buffer) - (global-set-key [S-f6] #'vcursor-scroll-down) - (global-set-key [S-f7] #'vcursor-scroll-up) - (global-set-key [S-f8] #'vcursor-end-of-buffer) - - (global-set-key [C-f9] #'vcursor-isearch-forward) - - (global-set-key [S-f9] #'vcursor-execute-key) - (global-set-key [S-f10] #'vcursor-execute-command) - ) - (t - (global-set-key (vcursor-cs-binding "up") #'vcursor-previous-line) - (global-set-key (vcursor-cs-binding "down") #'vcursor-next-line) - (global-set-key (vcursor-cs-binding "left") #'vcursor-backward-char) - (global-set-key (vcursor-cs-binding "right") #'vcursor-forward-char) - - (global-set-key (vcursor-cs-binding "return") #'vcursor-disable) - (global-set-key (vcursor-cs-binding "insert") #'vcursor-copy) - (global-set-key (vcursor-cs-binding "delete") #'vcursor-copy-word) - (global-set-key (vcursor-cs-binding "remove") #'vcursor-copy-word) - (global-set-key (vcursor-cs-binding "tab") #'vcursor-toggle-copy) - (global-set-key (vcursor-cs-binding "backtab") #'vcursor-toggle-copy) - (global-set-key (vcursor-cs-binding "home") #'vcursor-beginning-of-buffer) - (global-set-key (vcursor-cs-binding "up" t) #'vcursor-beginning-of-buffer) - (global-set-key (vcursor-cs-binding "end") #'vcursor-end-of-buffer) - (global-set-key (vcursor-cs-binding "down" t) #'vcursor-end-of-buffer) - (global-set-key (vcursor-cs-binding "prior") #'vcursor-scroll-down) - (global-set-key (vcursor-cs-binding "next") #'vcursor-scroll-up) - - (global-set-key (vcursor-cs-binding "f6") #'vcursor-other-window) - (global-set-key (vcursor-cs-binding "f7") #'vcursor-goto) - - (global-set-key (vcursor-cs-binding "select") - #'vcursor-swap-point) ; DEC keyboards - (global-set-key (vcursor-cs-binding "tab" t) #'vcursor-swap-point) - - (global-set-key (vcursor-cs-binding "find") - #'vcursor-isearch-forward) ; DEC keyboards - (global-set-key (vcursor-cs-binding "f8") #'vcursor-isearch-forward) - - (global-set-key (vcursor-cs-binding "left" t) #'vcursor-beginning-of-line) - (global-set-key (vcursor-cs-binding "right" t) #'vcursor-end-of-line) - - (global-set-key (vcursor-cs-binding "prior" t) #'vcursor-backward-word) - (global-set-key (vcursor-cs-binding "next" t) #'vcursor-forward-word) - - (global-set-key (vcursor-cs-binding "return" t) #'vcursor-copy-line) - - (global-set-key (vcursor-cs-binding "f9") #'vcursor-execute-key) - (global-set-key (vcursor-cs-binding "f10") #'vcursor-execute-command) - ))) - -;; TODO: Get rid of references to "oemacs", which was an ancient -;; MS-DOS compatible release of Emacs 19. -(defcustom vcursor-key-bindings nil - "How to bind keys when vcursor is loaded. -If t or `xterm', use the default bindings; if `oemacs', use -alternative key bindings. If nil, don't define any key bindings. - -Default is nil." - :type '(choice (const t) (const nil) (const xterm) (const oemacs)) - :set #'vcursor-bind-keys - :version "20.3") - -(defcustom vcursor-interpret-input nil - "If non-nil, input from the vcursor is treated as interactive input. -This will cause text insertion to be much slower. Note that no special -interpretation of strings is done: \"\\C-x\" is a string of four -characters. The default is simply to copy strings." - :type 'boolean - :version "20.3") - -(defcustom vcursor-string "**>" - "String used to show the vcursor position on dumb terminals." - :type 'string - :version "20.3") - -(defvar vcursor-overlay nil - "Overlay for the virtual cursor. -It is nil if that is not enabled.") - -(defvar vcursor-window nil - "Last window to have displayed the virtual cursor. -See the function `vcursor-find-window' for how this is used.") - -(defvar vcursor-last-command nil - "Non-nil if last command was a vcursor command. -The commands `vcursor-copy', `vcursor-relative-move' and the ones for -scrolling set this. It is used by the `vcursor-auto-disable' code.") -;; could do some memq-ing with last-command instead, but this will -;; automatically handle any new commands using the primitives. - -(defcustom vcursor-copy-flag nil - "Non-nil means moving vcursor should copy characters moved over to point." - :type 'boolean) - -(defvar vcursor-temp-goal-column nil - "Keeps track of temporary goal columns for the virtual cursor.") - -(defvar-keymap vcursor-map - :doc "Keymap for vcursor command." - "t" #'vcursor-use-vcursor-map - - "C-p" #'vcursor-previous-line - "C-n" #'vcursor-next-line - "C-b" #'vcursor-backward-char - "C-f" #'vcursor-forward-char - - "RET" #'vcursor-disable - "SPC" #'vcursor-copy - "C-y" #'vcursor-copy-word - "C-i" #'vcursor-toggle-copy - "<" #'vcursor-beginning-of-buffer - ">" #'vcursor-end-of-buffer - "M-v" #'vcursor-scroll-down - "C-v" #'vcursor-scroll-up - "o" #'vcursor-other-window - "g" #'vcursor-goto - "x" #'vcursor-swap-point - "C-s" #'vcursor-isearch-forward - "C-r" #'vcursor-isearch-backward - "C-a" #'vcursor-beginning-of-line - "C-e" #'vcursor-end-of-line - "M-w" #'vcursor-forward-word - "M-b" #'vcursor-backward-word - "M-l" #'vcursor-copy-line - "k" #'vcursor-execute-key - "M-x" #'vcursor-execute-command) -;; This seems unused, but it was done as part of define-prefix-command, -;; so let's keep it for now. -(fset 'vcursor-map vcursor-map) - -;; If vcursor-key-bindings is already set on loading, bind the keys now. -;; This hybrid way of doing it retains compatibility while allowing -;; customize to work smoothly. -(if vcursor-key-bindings - (vcursor-bind-keys 'vcursor-key-bindings vcursor-key-bindings)) - -(defun vcursor-locate () - "Go to the starting point of the virtual cursor. -If that's disabled, don't go anywhere but don't complain." - ;; This is where we go off-mass-shell. Assume there is a - ;; save-excursion to get us back to the pole, er, point. - (and (overlayp vcursor-overlay) - (overlay-buffer vcursor-overlay) - (set-buffer (overlay-buffer vcursor-overlay)) - (goto-char (overlay-start vcursor-overlay))) - ) - -(defun vcursor-find-window (&optional not-this new-win this-frame) - "Return a suitable window for displaying the virtual cursor. -This is the first window in cyclic order where the vcursor is visible. - -With optional NOT-THIS non-nil never return the current window. - -With NEW-WIN non-nil, display the virtual cursor buffer in another -window if the virtual cursor is not currently visible \(note, however, -that this function never changes `window-point'). - -With THIS-FRAME non-nil, don't search other frames for a new window -\(though if the vcursor is already off-frame then its current window is -always considered, and the value of `pop-up-frames' is always respected). - -Returns nil if the virtual cursor is not visible anywhere suitable. -Set `vcursor-window' to the returned value as a side effect." - ;; The order of priorities (respecting NOT-THIS) is (1) - ;; vcursor-window if the virtual cursor is visible there (2) any - ;; window displaying the virtual cursor (3) vcursor-window provided - ;; it is still displaying the buffer containing the virtual cursor and - ;; is not selected (4) any unselected window displaying the vcursor - ;; buffer (5) with NEW-WIN, a window selected by display-buffer (so - ;; the variables pop-up-windows and pop-up-frames are significant) - ;; (6) nil. - (let ((thiswin (selected-window)) winok winbuf) - (save-excursion - (vcursor-locate) - (or (and (window-live-p vcursor-window) - (eq (current-buffer) (window-buffer vcursor-window)) - (not (and not-this (eq thiswin vcursor-window)))) - (setq vcursor-window nil)) - (or (and vcursor-window ; choice 1 - (pos-visible-in-window-p (point) vcursor-window)) - (progn - (walk-windows - (lambda (win) - (and (not winok) - (eq (current-buffer) (window-buffer win)) - (not (and not-this (eq thiswin win))) - (cond - ((pos-visible-in-window-p (point) win) (setq winok win)) - ((eq thiswin win)) - ((not winbuf) (setq winbuf win))))) - nil (not this-frame)) - (setq vcursor-window - (cond - (winok) ; choice 2 - ((and vcursor-window ; choice 3 - (not (eq thiswin vcursor-window))) - vcursor-window) - (winbuf) ; choice 4 - (new-win (display-buffer (current-buffer) t)) ; choice 5 - (t nil))))))) ; default (choice 6) - vcursor-window - ) - -(defun vcursor-toggle-copy (&optional arg nomsg) - "Toggle copying to point when the vcursor is moved. -With a prefix ARG, turn on if non-negative, off if negative. -Display a message unless optional NOMSG is non-nil." - (interactive "P") - (setq vcursor-copy-flag - (cond ((not arg) (not vcursor-copy-flag)) - ((< (prefix-numeric-value arg) 0) nil) - (t)) - vcursor-last-command t) - (or nomsg (message "Copying from the vcursor is now %s." - (if vcursor-copy-flag "on" "off"))) - ) - -(defun vcursor-move (pt &optional leave-b leave-w) - "Move the virtual cursor to the character to the right of PT. -PT is an absolute location in the current buffer. With optional -LEAVE-B, PT is in the same buffer the vcursor is currently in. - -If the new virtual cursor location would not be visible, display it in -another window. With LEAVE-W, use the current `vcursor-window'." - ;; this works even if we're on-mass-shell, but usually we won't be. - - (save-excursion - (and leave-b (vcursor-check t) - (set-buffer (overlay-buffer vcursor-overlay))) - (if (eq pt (point-max)) - (setq pt (1- pt))) - (if (vcursor-check t) - (move-overlay vcursor-overlay pt (+ pt 1) (current-buffer)) - (setq vcursor-overlay (make-overlay pt (+ pt 1))) - (or window-system - (display-color-p) - (overlay-put vcursor-overlay 'before-string vcursor-string)) - (overlay-put vcursor-overlay 'face 'vcursor) - ;; 200 is purely an arbitrary "high" number. See bug#9663. - (overlay-put vcursor-overlay 'priority 200)) - (or leave-w (vcursor-find-window nil t)) - ;; vcursor-window now contains the right buffer - (or (pos-visible-in-window-p pt vcursor-window) - (set-window-point vcursor-window pt)))) - -(defun vcursor-insert (text) - "Insert TEXT, respecting `vcursor-interpret-input'." - (if vcursor-interpret-input - (setq unread-command-events - (append (listify-key-sequence text) unread-command-events)) - (insert text)) - ) - -(defun vcursor-relative-move (func &rest args) - "Call FUNC with arbitrary ARGS ... to move the virtual cursor. - -This is called by most of the virtual-cursor motion commands." - (let (text opoint) - (save-excursion - (vcursor-locate) - (setq opoint (point)) - (apply func args) - (and (eq opoint (point-max)) (eq opoint (point)) - (signal 'end-of-buffer nil)) - (vcursor-move (point)) - (if vcursor-copy-flag (setq text (buffer-substring opoint (point))))) - (if text (vcursor-insert text))) - (setq vcursor-last-command t) - ) - -(defun vcursor-goto (&optional arg) - "Move the real cursor to the virtual cursor position. -If the virtual cursor is (or was recently) visible in another window, -switch to that first. Without a prefix ARG, disable the virtual -cursor as well." - (interactive "P") - (and (vcursor-find-window) (select-window vcursor-window)) - (let ((buf (and vcursor-overlay (overlay-buffer vcursor-overlay)))) - (and buf (not (eq (current-buffer) buf)) (switch-to-buffer buf))) - (vcursor-locate) - (or arg (vcursor-disable)) - ) - -(defun vcursor-swap-point () - "Swap the location of point and that of the virtual cursor. - -The virtual cursor window becomes the selected window and the old -window becomes the virtual cursor window. If the virtual cursor would -not be visible otherwise, display it in another window." - (interactive) - (let ((buf (current-buffer)) (here (point)) (win (selected-window))) - (vcursor-goto) ; will disable the vcursor - (with-current-buffer buf - (setq vcursor-window win) - (vcursor-move here))) -) - -(defun vcursor-scroll-up (&optional n) - "Scroll up the vcursor window ARG lines or near full screen if none. -The vcursor will always appear in an unselected window." - (interactive "P") - (vcursor-window-funcall #'scroll-up n)) - -(defun vcursor-scroll-down (&optional n) - "Scroll down the vcursor window ARG lines or near full screen if none. -The vcursor will always appear in an unselected window." - (interactive "P") - (vcursor-window-funcall #'scroll-down n)) - -(defun vcursor-isearch-forward (&optional rep norecurs) - "Perform forward incremental search in the virtual cursor window. -The virtual cursor is moved to the resulting point; the ordinary -cursor stays where it was." - (interactive "P") - (vcursor-window-funcall #'isearch-forward rep norecurs) - ) - -(defun vcursor-isearch-backward (&optional rep norecurs) - "Perform backward incremental search in the virtual cursor window. -The virtual cursor is moved to the resulting point; the ordinary -cursor stays where it was." - (interactive "P") - (vcursor-window-funcall #'isearch-backward rep norecurs) - ) - -(defun vcursor-window-funcall (func &rest args) - "Call FUNC with ARGS ... in a virtual cursor window. -A window other than the currently-selected one will always be used. -The virtual cursor is moved to the value of point when the function -returns. - -If FUNC is a list, call the car of the list interactively, ignoring -ARGS. In this case, a new window will not be created if the vcursor -is visible in the current one." -;; that's to avoid messing up compatibility with old versions -;; by introducing a new argument, which would have to come before ARGS. - (vcursor-find-window (not (and (listp func) (vcursor-check t))) t) - (save-excursion - (let ((sw (selected-window)) text) - ;; We can't use save-window-excursion because that would restore - ;; the original display in the window we may want to alter. - (unwind-protect - (let ((here (point))) - (select-window vcursor-window) - (vcursor-locate) - (if (listp func) - (call-interactively (car func)) - (apply func args)) - (setq vcursor-window (selected-window)) - (and vcursor-copy-flag - (eq (current-buffer) (overlay-buffer vcursor-overlay)) - (setq text (buffer-substring here (point)))) - ;; vcursor-window and the current buffer are definitely - ;; right, so make sure vcursor-move doesn't pick others. - (vcursor-move (point) nil t)) - (select-window sw)) - (if text (vcursor-insert text)))) - (setq vcursor-last-command t) - ) - -(defun vcursor-get-char-count (func &rest args) - "Apply FUNC to ARGS ... and return the number of characters moved. -Point is temporarily set to the virtual cursor position before FUNC -is called. - -This is called by most of the virtual-cursor copying commands to find -out how much to copy." - (vcursor-check) - (with-current-buffer (overlay-buffer vcursor-overlay) - (save-excursion - (let ((start (goto-char (overlay-start vcursor-overlay)))) - (- (progn (apply func args) (point)) start))))) - -;; Make sure the virtual cursor is active. Unless arg is non-nil, -;; report an error if it is not. -(defun vcursor-check (&optional arg) - (cond - ((and (overlayp vcursor-overlay) (overlay-start vcursor-overlay)) - t) - (arg nil) - (t (error "The virtual cursor is not active now"))) - ) - -(define-minor-mode vcursor-use-vcursor-map - "Toggle the state of the vcursor key map. - -When on, the keys defined in it are mapped directly on top of the main -keymap, allowing you to move the vcursor with ordinary motion keys. -An indication \"!VC\" appears in the mode list. The effect is -local to the current buffer. -Disabling the vcursor automatically turns this off." - :keymap vcursor-map - :lighter " !VC") - -(defun vcursor-disable (&optional arg) - "Disable the virtual cursor. -Next time you use it, it will start from point. - -With a positive prefix ARG, the first window in cyclic order -displaying the virtual cursor (or which was recently displaying the -virtual cursor) will be deleted unless it's the selected window. - -With a negative prefix argument, enable the virtual cursor: make it -active at the same point as the real cursor. - -Copying mode is always turned off: the next use of the vcursor will -not copy text until you turn it on again." - (interactive "P") - (if (overlayp vcursor-overlay) - (progn - (delete-overlay vcursor-overlay) - (setq vcursor-overlay nil))) - (cond - ((not (vcursor-find-window t))) - ((or (not arg) (< (prefix-numeric-value arg) 0))) - ((delete-window vcursor-window))) - (cond - ((and arg (< (prefix-numeric-value arg) 0)) - (vcursor-move (point)) - (setq vcursor-window (selected-window))) - (vcursor-use-vcursor-map (vcursor-use-vcursor-map 0))) - (setq vcursor-copy-flag nil) - ) - -(defun vcursor-other-window (n &optional all-frames) - "Activate the virtual cursor in another window. -This is the next window cyclically after one currently showing the -virtual cursor, or else after the current selected window. If there -is no other window, the current window is split. - -Arguments N and optional ALL-FRAMES are the same as with `other-window'. -ALL-FRAMES is also used to decide whether to split the window." - - (interactive "p") - (if (one-window-p nil all-frames) - (display-buffer (current-buffer) t)) - (save-excursion - (save-window-excursion - ;; We don't use fancy vcursor-find-window trickery, since we're - ;; quite happy to have the vcursor cycle back into the current - ;; window. - (let ((win (vcursor-find-window nil nil (not all-frames)))) - (if win (select-window win)) - ;; else start from here - (other-window n all-frames) - (vcursor-disable -1)))) - ) - -(defun vcursor-next-line (arg) - "Move the virtual cursor forward ARG lines." - ;; This is next-line rewritten for the vcursor. Maybe it would - ;; be easier simply to rewrite line-move. - (interactive "p") - (let (temporary-goal-column opoint text) - (save-excursion - (vcursor-locate) - (setq temporary-goal-column - (if (or (eq last-command 'vcursor-next-line) - (eq last-command 'vcursor-previous-line)) - (progn - (setq last-command 'next-line) ; trick line-move - vcursor-temp-goal-column) - (if (and track-eol (eolp) - (or (not (bolp)) (eq last-command 'end-of-line))) - 9999 - (current-column))) - opoint (point)) - (line-move arg) - (and (eq opoint (point-max)) (eq opoint (point)) - (signal 'end-of-buffer nil)) - (if vcursor-copy-flag (setq text (buffer-substring opoint (point)))) - (vcursor-move (point)) - (setq vcursor-temp-goal-column temporary-goal-column - vcursor-last-command t)) - (if text (vcursor-insert text))) - ) - -(defun vcursor-previous-line (arg) - "Move the virtual cursor back ARG lines." - (interactive "p") - (vcursor-next-line (- arg)) - ) - -(defun vcursor-forward-char (arg) - "Move the virtual cursor forward ARG characters." - (interactive "p") - (vcursor-relative-move #'forward-char arg) - ) - -(defun vcursor-backward-char (arg) - "Move the virtual cursor backward ARG characters." - (interactive "p") - (vcursor-relative-move #'backward-char arg) - ) - -(defun vcursor-forward-word (arg) - "Move the virtual cursor forward ARG words." - (interactive "p") - (vcursor-relative-move #'forward-word arg) - ) - -(defun vcursor-backward-word (arg) - "Move the virtual cursor backward ARG words." - (interactive "p") - (vcursor-relative-move #'backward-word arg) - ) - -(defun vcursor-beginning-of-line (arg) - "Move the virtual cursor to beginning of its current line. -ARG is as for `beginning-of-line'." - (interactive "P") - (vcursor-relative-move #'beginning-of-line - (if arg (prefix-numeric-value arg))) - ) - -(defun vcursor-end-of-line (arg) - "Move the virtual cursor to end of its current line. -ARG is as for `end-of-line'." - (interactive "P") - (vcursor-relative-move #'end-of-line - (if arg (prefix-numeric-value arg))) - ) - -(defun vcursor-beginning-of-buffer (&optional arg) - "Move the virtual cursor to the beginning of its buffer. -ARG is as for `beginning-of-buffer'." - (interactive "P") - (vcursor-relative-move - (lambda (arg) - (goto-char (if arg (/ (* arg (- (point-max) (point-min))) 10) - (point-min)))) - (if arg (prefix-numeric-value arg))) - ) - -(defun vcursor-end-of-buffer (&optional arg) - "Move the virtual cursor to the end of its buffer. -ARG is as for `end-of-buffer'. - -Actually, the vcursor is moved to the second from last character or it -would be invisible." - (interactive "P") - (vcursor-relative-move - (lambda (arg) - (goto-char (if arg (- (point-max) - (/ (* arg (- (point-max) (point-min))) 10)) - (point-max)))) - (if arg (prefix-numeric-value arg))) - ) - -(defun vcursor-execute-command (cmd) - "Execute COMMAND for the virtual cursor. -COMMAND is called interactively. Not all commands (in fact, only a -small subset) are useful." - (interactive "CCommand: ") - (vcursor-window-funcall (list cmd)) - ) - -(defun vcursor-execute-key () - "Read a key sequence and execute the bound command for the virtual cursor. -The key sequence is read at the vcursor location. The command found -is called interactively, so prefix argument etc. are usable." - (interactive) - (let (cmd) - (save-excursion - ;; We'd like to avoid the display changing when we locate - ;; to the vcursor position and read a key sequence. - (vcursor-find-window (not (vcursor-check t)) t) - (save-window-excursion - (select-window vcursor-window) - (vcursor-locate) - (setq cmd (key-binding (read-key-sequence "Key sequence: "))))) - (vcursor-window-funcall (list cmd))) - ) - -(defun vcursor-copy (arg) - "Copy ARG characters from the virtual cursor position to point." - (interactive "p") - (vcursor-check) - (vcursor-insert - (with-current-buffer (overlay-buffer vcursor-overlay) - (let* ((ostart (overlay-start vcursor-overlay)) - (end (+ ostart arg))) - (prog1 - (buffer-substring ostart end) - (vcursor-move end))))) - (setq vcursor-last-command t) -) - -(defun vcursor-copy-word (arg) - "Copy ARG words from the virtual cursor position to point." - (interactive "p") - (vcursor-copy (vcursor-get-char-count #'forward-word arg)) - ) - -(defun vcursor-copy-line (arg) - "Copy up to ARGth line after virtual cursor position. -With no argument, copy to the end of the current line. - -Behavior with regard to newlines is similar (but not identical) to -`kill-line'; the main difference is that whitespace at the end of the -line is treated like ordinary characters." - (interactive "P") - (let* ((num (prefix-numeric-value arg)) - (count (vcursor-get-char-count #'end-of-line num))) - (vcursor-copy (if (or (= count 0) arg) (1+ count) count))) - ) - -(defun vcursor-post-command () - (and vcursor-auto-disable (not vcursor-last-command) - vcursor-overlay - (if (eq vcursor-auto-disable t) - (vcursor-disable) - (vcursor-toggle-copy -1 t))) - (setq vcursor-last-command nil) - ) - -(add-hook 'post-command-hook #'vcursor-post-command) - -(provide 'vcursor) - -;;; vcursor.el ends here -- 2.39.5