1 ;;; vcursor.el --- manipulate an alternative ("virtual") cursor
3 ;; Copyright (C) 1994, 1996, 1998 Free Software Foundation, Inc.
5 ;; Author: Peter Stephenson <pws@ibmth.df.unipi.it>
7 ;; Keywords: virtual cursor, convenience
9 ;; This file is part of GNU Emacs.
11 ;; GNU Emacs is free software; you can redistribute it and/or modify
12 ;; it under the terms of the GNU General Public License as published by
13 ;; the Free Software Foundation; either version 2, or (at your option)
16 ;; GNU Emacs is distributed in the hope that it will be useful,
17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 ;; GNU General Public License for more details.
21 ;; You should have received a copy of the GNU General Public License
22 ;; along with GNU Emacs; see the file COPYING. If not, write to the
23 ;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
24 ;; Boston, MA 02111-1307, USA.
31 ;; - *IMPORTANT* vcursor-key-bindings is now nil by default, to avoid
32 ;; side-effects when the package is loaded. This means no keys are
33 ;; bound by default. Use customize to change it to t to restore
34 ;; the old behaviour. (If you do it by hand in .emacs, it
35 ;; must come before vcursor is loaded.)
36 ;; - You can alter the main variables and the vcursor face via
37 ;; M-x customize: go to the Editing group and find Vcursor.
38 ;; - vcursor-auto-disable can now be 'copy (actually any value not nil
39 ;; or t), which means that copying from the vcursor will be turned
40 ;; off after any operation not involving the vcursor, but the
41 ;; vcursor itself will be left alone.
42 ;; - works on dumb terminals with Emacs 19.29 and later
43 ;; - new keymap vcursor-map for binding to a prefix key
44 ;; - vcursor-compare-windows substantially improved
45 ;; - vcursor-execute-{key,command} much better about using the
46 ;; right keymaps and arranging for the correct windows to be used
47 ;; - vcursor-window-funcall can call functions interactively
48 ;; - vcursor-interpret-input for special effects
53 ;; Virtual cursor commands. I got this idea from the old BBC micro.
54 ;; You need Emacs 19 or 20 and a window system for the best effects.
55 ;; For character terminals, at least Emacs 19.29 is required
56 ;; (special behaviour for the overlay property
57 ;; "before-string" must be implemented). Search for "dumb terminals"
58 ;; for more information.
60 ;; This is much easier to use than the instructions are to read.
61 ;; First, you need to let vcursor define some keys: setting
62 ;; vcursor-key-bindings to t before loading, or by customize, will
63 ;; define various keys with the prefix C-S. You'll have to read
64 ;; further if you don't want this. Then I suggest you simply load it
65 ;; and play around with holding down Ctrl and Shift and pressing up,
66 ;; down, left, right, tab, return, and see what happens. (Find a
67 ;; scratch buffer before using C-S-tab: that toggles copying.)
69 ;; Most of the functions described in this documentation are in
70 ;; parentheses so that if you have the package loaded you can type C-h
71 ;; f on top of them for help.
73 ;; Using the cursor keys with both control and shift held down moves
74 ;; around a virtual cursor, which is initially at point. When active,
75 ;; it appears with an underline through it to distinguish it from the
76 ;; normal cursor. You can then use one of the other commands to copy
77 ;; characters from the location of the virtual cursor to point. This
78 ;; is very useful, for example, when copying some previous text while
79 ;; making changes to it at the same time, since you never have to move
80 ;; the "real" cursor away from where you are inserting.
82 ;; The remaining default key bindings are based around the PC-type
83 ;; cluster found above the cursor keys on a lot of keyboards, the
84 ;; function keys which my limited knowledge of X terminals expects to
85 ;; find at the top. Some functions are duplicated in more obvious
86 ;; places for the X version.
88 ;; All the keybindings require you to hold down control and shift at
89 ;; once. I assumed this combination wouldn't be heavily bound by most
90 ;; people and that it would be easy to type with the left hand.
91 ;; Inevitably it will clash with some other packages, but I can't help
92 ;; that: an intuitive binding is a prerequisite here. See below for
93 ;; other alternatives (search for "Oemacs"). There is also a keymap
94 ;; which you can bind to a prefix key, which may give some more
95 ;; intuitive alternatives in some cases, see `The vcursor keymap' below.
97 ;; Holding down control and shift and pressing insert (vcursor-copy)
98 ;; copies one character from wherever the virtual cursor is to point;
99 ;; point and the virtual cursor advance in the separate and equal
100 ;; station to which... (etc.). M-C-S-return (vcursor-copy-line)
101 ;; copies to the end of the line instead of just one character,
102 ;; C-S-delete or C-S-remove (vcursor-copy-word) copies a word.
104 ;; A more general way of copying is to use C-S-tab, which is a toggle.
105 ;; In the "on" state, moving the virtual cursor will copy the
106 ;; moved-over text to the normal cursor position (including when going
107 ;; backwards, though each piece of text moved over is copied forwards:
108 ;; compare the behaviour of C-S-up and C-S-left).
110 ;; However, that's just a small part of the magic. If the virtual
111 ;; cursor goes off the display, it will be redisplayed in some other
112 ;; window. (See the function (vcursor-find-window) for details of how
113 ;; this window is chosen.) This gives you fingertip control over two
116 ;; C-S-return (vcursor-disable) disables the virtual cursor, removing
117 ;; it so that it starts from point whenever you move it again --- note
118 ;; that simply moving the cursor and virtual cursor on top of one
119 ;; another does not have this effect.
121 ;; If you give C-S-return a positive prefix arg, it will also delete the
122 ;; window (unless it's the current one). Whenever the virtual cursor
123 ;; goes off-screen in its own window, point in that window is moved as
124 ;; well to restore it to view. (It's easier that way, that's why.
125 ;; However, point doesn't move unless the view in the window does, so
126 ;; it's not tied to the virtual cursor location.)
128 ;; You can also use C-S-return with a negative prefix argument which
129 ;; forces the vcursor to appear at point. This is particularly useful if
130 ;; you actually want to edit in another window but would like to
131 ;; remember the current cursor location for examining or copying from
132 ;; that buffer. (I just hit C-S-right C-S-left, but I'm a hopeless
135 ;; There is also C-S-f6 (vcursor-other-window) which behaves like
136 ;; C-x o on the virtual rather than the real cursor, except that it
137 ;; will create another window if necessary.
139 ;; The keys C-S-prior (vcursor-scroll-down) and C-S-next
140 ;; (vcursor-scroll-up) (i.e., PageUp and PageDown) will scroll the
141 ;; virtual cursor window, appropriately chosen. They will always
142 ;; create a new window or take over an old one if necessary.
143 ;; Likewise, M-C-S-left and M-C-S-right move you to the
144 ;; beginning or end of a line, C-S-home and C-S-end the
145 ;; beginning or end of a buffer (these are also on M-C-S-up and
146 ;; M-C-S-down for those of us stuck with DEC keyboards).
148 ;; C-S-f7 (vcursor-goto) will take you to the vcursor position
149 ;; (swapping windows if it seems sensible) and (unless you give it a
150 ;; prefix argument) delete the virtual cursor, so this is useful for
151 ;; you to take over editing at the virtual cursor position. It is not
152 ;; an error if the virtual cursor is not active; it simply leaves you
153 ;; at point, because that is where the virtual cursor would start
156 ;; In a similar vein, M-C-S-tab (hope your left hand's flexible;
157 ;; C-S-select on DEC keyboards) (vcursor-swap-point) will take you to
158 ;; the virtual cursor position but simultaneously put the virtual
159 ;; cursor at the old cursor position. It is also supposed to ensure
160 ;; that both are visible.
162 ;; C-S-f8 (C-S-find on DEC keyboards) (vcursor-isearch-forward)
163 ;; allows you to do an isearch in another window. It works a bit like
164 ;; vcursor-scroll-*; it moves into another window, calls isearch
165 ;; there, and sets the virtual cursor position to the point found. In
166 ;; other words, it works just like isearch but with the virtual cursor
167 ;; instead of the real one (that's why it's called a "virtual
168 ;; cursor"). While you are isearching, you are editing in the virtual
169 ;; cursor window, but when you have finished you return to where you
170 ;; started. Note that once you are in isearch all the keys are normal
171 ;; --- use C-s, not C-S-f8, to search for the next occurrence.
173 ;; If you set the variable vcursor-auto-disable, then any command
174 ;; which does not involve moving or copying from the virtual cursor
175 ;; causes the virtual cursor to be disabled. If you set it to non-nil
176 ;; but not t, then the vcursor itself will remain active, but copying
177 ;; will be turned off, so that the next time the vcursor is moved no
178 ;; text is copied over. Experience shows that this setting is
179 ;; particularly useful. If you don't intend to use this, you can
180 ;; comment out the `add-hook' line at the bottom of this file. (This
181 ;; feature partially emulates the way the "copy" key on the BBC micro
182 ;; worked; actually, the copy cursor was homed when you hit return.
183 ;; This was in keeping with the line-by-line way of entering BASIC,
184 ;; but is less appropriate here.)
186 ;; vcursor-compare-windows is now a reliable adaption of
187 ;; compare-windows, which compares between point in the current buffer
188 ;; and the vcursor location in the other one. It is an error if
189 ;; vcursor is not set, however it will be brought up in another window
190 ;; if it is not currently visible. The prefix argument acts just like
191 ;; compare-windows, ignoring whitespace if set. (In versions before
192 ;; 1.6, this simply called compare-windows, which was much less likely
193 ;; to pick the two windows you wanted.)
195 ;; There is a way of moving the virtual cursor using ordinary
196 ;; commands: C-S-f9 (vcursor-execute-key) reads a key string,
197 ;; moves to the virtual cursor position, executes the command bound to
198 ;; the string, then returns to the original point. Thus C-S-f9 M-m
199 ;; moves the virtual cursor back to the first non-whitespace character
200 ;; on its line. As the command is called interactively all the usual
201 ;; ways of passing information to the command called, such as by a
202 ;; prefix argument, are available. This has many uses not necessarily
203 ;; related to moving the vcursor itself; it can do essentially
204 ;; everything that the \C-x 4 series of commands can do and a lot
205 ;; more. Note, however, that a new window is not used if the vcursor
206 ;; is visible in the current one: this can lead to some strange effects,
207 ;; but it is preferable to making a new window every time the vcursor
208 ;; is moved in this may.
210 ;; C-S-f10 (C-S-x) (vcursor-execute-command) behaves the same way but
211 ;; you enter the name of the command. To do anything really
212 ;; complicated, you are better off using M-C-S-tab
213 ;; (vcursor-swap-point), doing whatever it is, then calling M-C-S-tab
216 ;; If you want to add your own moving or copying functions you should
217 ;; be able to do this fairly easily with (vcursor-relative-move) and
218 ;; (vcursor-copy) together with (vcursor-get-char-count). If you want to
219 ;; do something in a different window, use (vcursor-window-funcall).
224 ;; There is an alternative set of key bindings which will be used
225 ;; automatically for a PC if Oemacs is detected. This set uses separate
226 ;; control, shift and meta keys with function keys 1 to 10. In
227 ;; particular, movement keys are concentrated on f5 to f8 with (in
228 ;; increasing order of distance travelled) C-, M- and S- as prefixes.
229 ;; See the actual bindings below (search for C-f1). This is because the
230 ;; C-S- prefix is represented by weird key sequences and the set is
231 ;; incomplete; if you don't mind that, some hints are given in comments
234 ;; You can specify the usual or the Oemacs bindings by setting the
235 ;; variable vcursor-key-bindings to `xterm' or `oemacs'. You can also set
236 ;; it to nil, in which case vcursor will not make any key bindings
237 ;; and you can define your own. The default is t, which makes vcursor
238 ;; guess (it will use xterm unless it thinks Oemacs is running). The
239 ;; oemacs set will work on an X terminal with function keys, but the
240 ;; xterm set will not work under Oemacs.
242 ;; Usage on dumb terminals
243 ;; =======================
245 ;; If Emacs has set the variable window-system to nil, vcursor will
246 ;; assume that overlays cannot be displayed in a different face,
247 ;; and will instead use a string (the variable vcursor-string, by
248 ;; default "**>") to show its position. This was first implemented
249 ;; in Emacs 19.29. Unlike the old-fashioned overlay arrow (as used
250 ;; by debuggers), this appears between existing text, which can
251 ;; make it hard to read if you're not used to it. (This seemed the
252 ;; better option here.) This means moving the vcursor up and down is
253 ;; a very efficient way of locating it!
255 ;; Everything else should function as expected, but there is no way to
256 ;; get an easy key binding for the vcursor keys on a generic terminal.
257 ;; Consequently a special keymap is defined for you to use traditional
258 ;; methods: the keymap, however, is available on any terminal type.
260 ;; The vcursor keymap
261 ;; ==================
263 ;; In addition to any other bindings, vcursor-map contains key definitions
264 ;; for handling the vcursor. You should assign this to a prefix key
265 ;; in the usual way, e.g.
266 ;; (global-set-key [f14] vcursor-map)
267 ;; and also as usual \C-h in this map will list the key definitions, which
268 ;; are designed to be easy to remember.
270 ;; A special feature is provided by (vcursor-toggle-vcursor-map), bound
271 ;; to t in that keymap. With this in effect, the main keymap
272 ;; is overridden by the vcursor map, so keys like \C-p and so on
273 ;; move the vcursor instead. Remember how to turn it off (type t),
274 ;; or you are in serious trouble! Note that the cursor keys are not
275 ;; bound by default in this keymap and will continue to move the
281 ;; Just occasionally, you may want to pretend the strings copied from
282 ;; the vcursor position are to be interpreted as if you had typed them
283 ;; from the keyboard. Normally, they will just insert themselves anyway,
284 ;; but in some modes (Info and calc for example) typing ordinary characters
285 ;; does something else. To get this effect, set
286 ;; vcursor-interpret-input to t. This is normally not a good idea as
287 ;; interpreting input is very much slower than copying text.
292 ;; - The vcursor will not move to point-max, since otherwise it would
293 ;; disappear. However, no error is flagged as point-max is a valid
294 ;; point in the buffer. Thus cursor right or down at the second
295 ;; last point in the file does not flag an error, which is inconsistent,
296 ;; and if copying is on the last character (typically newline) will
297 ;; be repeatedly copied. (I've tried making it flag an error
298 ;; instead and that's worse since often the vcursor is sent to
299 ;; point in some other window, which may be point-max.)
300 ;; - The vcursor widens when over a tab character or right at the
301 ;; end of the line. You're welcome to consider this a feature;
302 ;; it's just a part of how overlays work.
303 ;; - The vcursor obscures the real cursor. Creative use of overlays
305 ;; - The vcursor does not remember its own previous positions. If
306 ;; you cycle it back into a window it was in before, it will be at
307 ;; point in that window. Often, that is where a previous recenter
308 ;; left point, not where the vcursor was before.
309 ;; (Note, however, that the vcursor does remember where it *is*,
310 ;; even if it's off-screen. This can also lead to surprises, but I
311 ;; don't think it's a bug.)
312 ;; - vcursor-window-funcall could perhaps be smarter about restoring
313 ;; the previous window state on failure.
314 ;; - The logic in vcursor-find-window is rather complicated and
315 ;; therefore bug-prone, though in practice it seems to work OK.
317 ;; Possible enhnacements:
318 ;; It would be easy to implement vcursor-push (save vcursor position
319 ;; as mark and deactivate) and vcursor-pop (deactivate vcursor and
320 ;; move to last pushed position) functions.
324 (eval-when-compile (require 'compare-w
))
326 (defgroup vcursor nil
327 "Manipulate an alternative (\"virtual\") cursor."
332 '((((class color
)) (:foreground
"blue" :background
"cyan" :underline t
))
333 (t (:inverse-video t
:underline t
)))
334 "Face for the virtual cursor."
337 (defcustom vcursor-auto-disable nil
338 "*If non-nil, disable the virtual cursor after use.
339 Any non-vcursor command will force `vcursor-disable' to be called.
340 If non-nil but not t, just make sure copying is toggled off, but don't
341 disable the vcursor."
342 :type
'(choice (const t
) (const nil
) (const copy
))
345 ;; Needed for defcustom, must be up here
346 (defun vcursor-cs-binding (base &optional meta
)
347 (vector (let ((key (list 'control
'shift
(intern base
))))
352 (defun vcursor-bind-keys (var value
)
353 "Alter the value of the variable VAR to VALUE, binding keys as required.
354 VAR is usually vcursor-key-bindings. Normally this function is called
355 on loading vcursor and from the customize package."
358 ((not value
));; don't set any key bindings
359 ((or (eq value
'oemacs
)
360 (and (eq value t
) (fboundp 'oemacs-version
)))
361 (global-set-key [C-f1
] 'vcursor-toggle-copy
)
362 (global-set-key [C-f2
] 'vcursor-copy
)
363 (global-set-key [C-f3
] 'vcursor-copy-word
)
364 (global-set-key [C-f4
] 'vcursor-copy-line
)
366 (global-set-key [S-f1
] 'vcursor-disable
)
367 (global-set-key [S-f2
] 'vcursor-other-window
)
368 (global-set-key [S-f3
] 'vcursor-goto
)
369 (global-set-key [S-f4
] 'vcursor-swap-point
)
371 (global-set-key [C-f5
] 'vcursor-backward-char
)
372 (global-set-key [C-f6
] 'vcursor-previous-line
)
373 (global-set-key [C-f7
] 'vcursor-next-line
)
374 (global-set-key [C-f8
] 'vcursor-forward-char
)
376 (global-set-key [M-f5
] 'vcursor-beginning-of-line
)
377 (global-set-key [M-f6
] 'vcursor-backward-word
)
378 (global-set-key [M-f6
] 'vcursor-forward-word
)
379 (global-set-key [M-f8
] 'vcursor-end-of-line
)
381 (global-set-key [S-f5
] 'vcursor-beginning-of-buffer
)
382 (global-set-key [S-f6
] 'vcursor-scroll-down
)
383 (global-set-key [S-f7
] 'vcursor-scroll-up
)
384 (global-set-key [S-f8
] 'vcursor-end-of-buffer
)
386 (global-set-key [C-f9
] 'vcursor-isearch-forward
)
388 (global-set-key [S-f9
] 'vcursor-execute-key
)
389 (global-set-key [S-f10
] 'vcursor-execute-command
)
391 ;;; Partial dictionary of Oemacs key sequences for you to roll your own,
392 ;;; e.g C-S-up: (global-set-key "\M-[\C-f\M-\C-m" 'vcursor-previous-line)
394 ;;; "\M-[\C-f\M-\C-m" C-S-up
395 ;;; "\M-[\C-f\M-\C-q" C-S-down
396 ;;; "\M-[\C-fs" C-S-left
397 ;;; "\M-[\C-ft" C-S-right
399 ;;; "\M-[\C-fw" C-S-home
400 ;;; "\M-[\C-b\C-o" S-tab
401 ;;; "\M-[\C-f\M-\C-r" C-S-insert
402 ;;; "\M-[\C-fu" C-S-end
403 ;;; "\M-[\C-f\M-\C-s" C-S-delete
404 ;;; "\M-[\C-f\M-\C-d" C-S-prior
405 ;;; "\M-[\C-fv" C-S-next
407 ;;; "\M-[\C-f^" C-S-f1
408 ;;; "\M-[\C-f_" C-S-f2
409 ;;; "\M-[\C-f`" C-S-f3
410 ;;; "\M-[\C-fa" C-S-f4
411 ;;; "\M-[\C-fb" C-S-f5
412 ;;; "\M-[\C-fc" C-S-f6
413 ;;; "\M-[\C-fd" C-S-f7
414 ;;; "\M-[\C-fe" C-S-f8
415 ;;; "\M-[\C-ff" C-S-f9
416 ;;; "\M-[\C-fg" C-S-f10
419 (global-set-key (vcursor-cs-binding "up") 'vcursor-previous-line
)
420 (global-set-key (vcursor-cs-binding "down") 'vcursor-next-line
)
421 (global-set-key (vcursor-cs-binding "left") 'vcursor-backward-char
)
422 (global-set-key (vcursor-cs-binding "right") 'vcursor-forward-char
)
424 (global-set-key (vcursor-cs-binding "return") 'vcursor-disable
)
425 (global-set-key (vcursor-cs-binding "insert") 'vcursor-copy
)
426 (global-set-key (vcursor-cs-binding "delete") 'vcursor-copy-word
)
427 (global-set-key (vcursor-cs-binding "remove") 'vcursor-copy-word
)
428 (global-set-key (vcursor-cs-binding "tab") 'vcursor-toggle-copy
)
429 (global-set-key (vcursor-cs-binding "backtab") 'vcursor-toggle-copy
)
430 (global-set-key (vcursor-cs-binding "home") 'vcursor-beginning-of-buffer
)
431 (global-set-key (vcursor-cs-binding "up" t
) 'vcursor-beginning-of-buffer
)
432 (global-set-key (vcursor-cs-binding "end") 'vcursor-end-of-buffer
)
433 (global-set-key (vcursor-cs-binding "down" t
) 'vcursor-end-of-buffer
)
434 (global-set-key (vcursor-cs-binding "prior") 'vcursor-scroll-down
)
435 (global-set-key (vcursor-cs-binding "next") 'vcursor-scroll-up
)
437 (global-set-key (vcursor-cs-binding "f6") 'vcursor-other-window
)
438 (global-set-key (vcursor-cs-binding "f7") 'vcursor-goto
)
440 (global-set-key (vcursor-cs-binding "select")
441 'vcursor-swap-point
) ; DEC keyboards
442 (global-set-key (vcursor-cs-binding "tab" t
) 'vcursor-swap-point
)
444 (global-set-key (vcursor-cs-binding "find")
445 'vcursor-isearch-forward
) ; DEC keyboards
446 (global-set-key (vcursor-cs-binding "f8") 'vcursor-isearch-forward
)
448 (global-set-key (vcursor-cs-binding "left" t
) 'vcursor-beginning-of-line
)
449 (global-set-key (vcursor-cs-binding "right" t
) 'vcursor-end-of-line
)
451 (global-set-key (vcursor-cs-binding "prior" t
) 'vcursor-backward-word
)
452 (global-set-key (vcursor-cs-binding "next" t
) 'vcursor-forward-word
)
454 (global-set-key (vcursor-cs-binding "return" t
) 'vcursor-copy-line
)
456 (global-set-key (vcursor-cs-binding "f9") 'vcursor-execute-key
)
457 (global-set-key (vcursor-cs-binding "f10") 'vcursor-execute-command
)
460 (defcustom vcursor-key-bindings nil
461 "*How to bind keys when vcursor is loaded.
462 If t, guess; if xterm, use bindings suitable for an X terminal; if
463 oemacs, use bindings which work on a PC with Oemacs. If nil, don't
464 define any key bindings.
467 :type
'(choice (const t
) (const nil
) (const xterm
) (const oemacs
))
469 :set
'vcursor-bind-keys
472 (defcustom vcursor-interpret-input nil
473 "*If non-nil, input from the vcursor is treated as interactive input.
474 This will cause text insertion to be much slower. Note that no special
475 interpretation of strings is done: \"\C-x\" is a string of four
476 characters. The default is simply to copy strings."
481 (defcustom vcursor-string
"**>"
482 "String used to show the vcursor position on dumb terminals."
487 (defvar vcursor-overlay nil
488 "Overlay for the virtual cursor.
489 It is nil if that is not enabled.")
491 (defvar vcursor-window nil
492 "Last window to have displayed the virtual cursor.
493 See the function `vcursor-find-window' for how this is used.")
495 (defvar vcursor-last-command nil
496 "Non-nil if last command was a vcursor command.
497 The commands `vcursor-copy', `vcursor-relative-move' and the ones for
498 scrolling set this. It is used by the `vcursor-auto-disable' code.")
499 ;; could do some memq-ing with last-command instead, but this will
500 ;; automatically handle any new commands using the primitives.
502 (defcustom vcursor-copy-flag nil
503 "*Non-nil means moving vcursor should copy characters moved over to point."
507 (defvar vcursor-temp-goal-column nil
508 "Keeps track of temporary goal columns for the virtual cursor.")
510 (defvar vcursor-use-vcursor-map nil
511 "Non-nil if the vcursor map is mapped directly onto the main keymap.
512 See vcursor-toggle-vcursor-map.")
513 (make-variable-buffer-local 'vcursor-use-vcursor-map
)
515 (defvar vcursor-map nil
"Keymap for vcursor command.")
516 (define-prefix-command 'vcursor-map
)
518 (define-key vcursor-map
"t" 'vcursor-toggle-vcursor-map
)
520 (define-key vcursor-map
"\C-p" 'vcursor-previous-line
)
521 (define-key vcursor-map
"\C-n" 'vcursor-next-line
)
522 (define-key vcursor-map
"\C-b" 'vcursor-backward-char
)
523 (define-key vcursor-map
"\C-f" 'vcursor-forward-char
)
525 (define-key vcursor-map
"\r" 'vcursor-disable
)
526 (define-key vcursor-map
" " 'vcursor-copy
)
527 (define-key vcursor-map
"\C-y" 'vcursor-copy-word
)
528 (define-key vcursor-map
"\C-i" 'vcursor-toggle-copy
)
529 (define-key vcursor-map
"<" 'vcursor-beginning-of-buffer
)
530 (define-key vcursor-map
">" 'vcursor-end-of-buffer
)
531 (define-key vcursor-map
"\M-v" 'vcursor-scroll-down
)
532 (define-key vcursor-map
"\C-v" 'vcursor-scroll-up
)
533 (define-key vcursor-map
"o" 'vcursor-other-window
)
534 (define-key vcursor-map
"g" 'vcursor-goto
)
535 (define-key vcursor-map
"x" 'vcursor-swap-point
)
536 (define-key vcursor-map
"\C-s" 'vcursor-isearch-forward
)
537 (define-key vcursor-map
"\C-r" 'vcursor-isearch-backward
)
538 (define-key vcursor-map
"\C-a" 'vcursor-beginning-of-line
)
539 (define-key vcursor-map
"\C-e" 'vcursor-end-of-line
)
540 (define-key vcursor-map
"\M-w" 'vcursor-forward-word
)
541 (define-key vcursor-map
"\M-b" 'vcursor-backward-word
)
542 (define-key vcursor-map
"\M-l" 'vcursor-copy-line
)
543 (define-key vcursor-map
"c" 'vcursor-compare-windows
)
544 (define-key vcursor-map
"k" 'vcursor-execute-key
)
545 (define-key vcursor-map
"\M-x" 'vcursor-execute-command
)
547 ;; If vcursor-key-bindings is already set on loading, bind the keys now.
548 ;; This hybrid way of doing it retains compatibility while allowing
549 ;; customize to work smoothly.
550 (if vcursor-key-bindings
551 (vcursor-bind-keys 'vcursor-key-bindings vcursor-key-bindings
))
553 (defun vcursor-locate ()
554 "Go to the starting point of the virtual cursor.
555 If that's disabled, don't go anywhere but don't complain."
556 ;; This is where we go off-mass-shell. Assume there is a
557 ;; save-excursion to get us back to the pole, er, point.
559 (and (overlayp vcursor-overlay
)
560 (overlay-buffer vcursor-overlay
)
561 (set-buffer (overlay-buffer vcursor-overlay
))
562 (goto-char (overlay-start vcursor-overlay
)))
565 (defun vcursor-find-window (&optional not-this new-win this-frame
)
566 "Return a suitable window for displaying the virtual cursor.
567 This is the first window in cyclic order where the vcursor is visible.
569 With optional NOT-THIS non-nil never return the current window.
571 With NEW-WIN non-nil, display the virtual cursor buffer in another
572 window if the virtual cursor is not currently visible \(note, however,
573 that this function never changes window-point\).
575 With THIS-FRAME non-nil, don't search other frames for a new window
576 \(though if the vcursor is already off-frame then its current window is
577 always considered, and the value of `pop-up-frames' is always respected\).
579 Returns nil if the virtual cursor is not visible anywhere suitable.
580 Set `vcursor-window' to the returned value as a side effect."
582 ;; The order of priorities (respecting NOT-THIS) is (1)
583 ;; vcursor-window if the virtual cursor is visible there (2) any
584 ;; window displaying the virtual cursor (3) vcursor-window provided
585 ;; it is still displaying the buffer containing the virtual cursor and
586 ;; is not selected (4) any unselected window displaying the vcursor
587 ;; buffer (5) with NEW-WIN, a window selected by display-buffer (so
588 ;; the variables pop-up-windows and pop-up-frames are significant)
591 (let ((thiswin (selected-window)) winok winbuf
)
594 (or (and (window-live-p vcursor-window
)
595 (eq (current-buffer) (window-buffer vcursor-window
))
596 (not (and not-this
(eq thiswin vcursor-window
))))
597 (setq vcursor-window nil
))
598 (or (and vcursor-window
; choice 1
599 (pos-visible-in-window-p (point) vcursor-window
))
605 (eq (current-buffer) (window-buffer win
))
606 (not (and not-this
(eq thiswin win
)))
608 ((pos-visible-in-window-p (point) win
) (setq winok win
))
610 ((not winbuf
) (setq winbuf win
))))))
611 nil
(not this-frame
))
615 ((and vcursor-window
; choice 3
616 (not (eq thiswin vcursor-window
))) vcursor-window
)
618 (new-win (display-buffer (current-buffer) t
)) ; choice 5
619 (t nil
))))))) ; default (choice 6)
623 (defun vcursor-toggle-copy (&optional arg nomsg
)
624 "Toggle copying to point when the vcursor is moved.
625 With a prefix ARG, turn on if non-negative, off if negative.
626 Display a message unless optional NOMSG is non-nil."
628 (setq vcursor-copy-flag
629 (cond ((not arg
) (not vcursor-copy-flag
))
630 ((< (prefix-numeric-value arg
) 0) nil
)
632 vcursor-last-command t
)
633 (or nomsg
(message "Copying from the vcursor is now %s."
634 (if vcursor-copy-flag
"on" "off")))
637 (defun vcursor-move (pt &optional leave-b leave-w
)
638 "Move the virtual cursor to the character to the right of PT.
639 PT is an absolute location in the current buffer. With optional
640 LEAVE-B, PT is in the same buffer the vcursor is currently in.
642 If the new virtual cursor location would not be visible, display it in
643 another window. With LEAVE-W, use the current `vcursor-window'."
644 ;; this works even if we're on-mass-shell, but usually we won't be.
647 (and leave-b
(vcursor-check t
)
648 (set-buffer (overlay-buffer vcursor-overlay
)))
649 (if (eq pt
(point-max))
651 (if (vcursor-check t
)
652 (move-overlay vcursor-overlay pt
(+ pt
1) (current-buffer))
653 (setq vcursor-overlay
(make-overlay pt
(+ pt
1)))
656 (overlay-put vcursor-overlay
'before-string vcursor-string
))
657 (overlay-put vcursor-overlay
'face
'vcursor
))
658 (or leave-w
(vcursor-find-window nil t
))
659 ;; vcursor-window now contains the right buffer
660 (or (pos-visible-in-window-p pt vcursor-window
)
661 (set-window-point vcursor-window pt
)))
664 (defun vcursor-insert (text)
665 "Insert TEXT, respecting `vcursor-interpret-input'."
666 (if vcursor-interpret-input
667 (setq unread-command-events
668 (append (listify-key-sequence text
) unread-command-events
))
672 (defun vcursor-relative-move (fn &rest args
)
673 "Use FUNCTION with arbitrary ARG1 ... to move the virtual cursor.
675 This is called by most of the virtual-cursor motion commands."
679 (setq opoint
(point))
681 (and (eq opoint
(point-max)) (eq opoint
(point))
682 (signal 'end-of-buffer nil
))
683 (vcursor-move (point))
684 (if vcursor-copy-flag
(setq text
(buffer-substring opoint
(point)))))
685 (if text
(vcursor-insert text
)))
686 (setq vcursor-last-command t
)
689 (defun vcursor-goto (&optional arg
)
690 "Move the real cursor to the virtual cursor position.
691 If the virtual cursor is (or was recently) visible in another window,
692 switch to that first. Without a prefix ARG, disable the virtual
696 (and (vcursor-find-window) (select-window vcursor-window
))
697 (let ((buf (and vcursor-overlay
(overlay-buffer vcursor-overlay
))))
698 (and buf
(not (eq (current-buffer) buf
)) (switch-to-buffer buf
)))
700 (or arg
(vcursor-disable))
703 (defun vcursor-swap-point ()
704 "Swap the location of point and that of the virtual cursor.
706 The virtual cursor window becomes the selected window and the old
707 window becomes the virtual cursor window. If the virtual cursor would
708 not be visible otherwise, display it in another window."
711 (let ((buf (current-buffer)) (here (point)) (win (selected-window)))
712 (vcursor-goto) ; will disable the vcursor
715 (setq vcursor-window win
)
716 (vcursor-move here
)))
719 (defun vcursor-scroll-up (&optional n
)
720 "Scroll up the vcursor window ARG lines or near full screen if none.
721 The vcursor will always appear in an unselected window."
724 (vcursor-window-funcall 'scroll-up n
)
727 (defun vcursor-scroll-down (&optional n
)
728 "Scroll down the vcursor window ARG lines or near-full screen if none.
729 The vcursor will always appear in an unselected window."
732 (vcursor-window-funcall 'scroll-down n
)
735 (defun vcursor-isearch-forward (&optional rep norecurs
)
736 "Perform forward incremental search in the virtual cursor window.
737 The virtual cursor is moved to the resulting point; the ordinary
738 cursor stays where it was."
741 (vcursor-window-funcall 'isearch-forward rep norecurs
)
744 (defun vcursor-isearch-backward (&optional rep norecurs
)
745 "Perform backward incremental search in the virtual cursor window.
746 The virtual cursor is moved to the resulting point; the ordinary
747 cursor stays where it was."
750 (vcursor-window-funcall 'isearch-backward rep norecurs
)
753 (defun vcursor-window-funcall (func &rest args
)
754 "Call FUNC with ARGS ... in a virtual cursor window.
755 A window other than the currently-selected one will always be used.
756 The virtual cursor is moved to the value of point when the function
759 If FUNC is a list, call the car of the list interactively, ignoring
760 ARGS. In this case, a new window will not be created if the vcursor
761 is visible in the current one."
762 ;; that's to avoid messing up compatibility with old versions
763 ;; by introducing a new argument, which would have to come before ARGS.
765 (vcursor-find-window (not (and (listp func
) (vcursor-check t
))) t
)
767 (let ((sw (selected-window)) text
)
768 ;; We can't use save-window-excursion because that would restore
769 ;; the original display in the window we may want to alter.
771 (let ((here (point)))
772 (select-window vcursor-window
)
775 (call-interactively (car func
))
777 (setq vcursor-window
(selected-window))
778 (and vcursor-copy-flag
779 (eq (current-buffer) (overlay-buffer vcursor-overlay
))
780 (setq text
(buffer-substring here
(point))))
781 ;; vcursor-window and the current buffer are definitely
782 ;; right, so make sure vcursor-move doesn't pick others.
783 (vcursor-move (point) nil t
))
785 (if text
(vcursor-insert text
))))
786 (setq vcursor-last-command t
)
789 (defun vcursor-get-char-count (fn &rest args
)
790 "Apply FN to ARG1 ... and return the number of characters moved.
791 Point is temporarily set to the virtual cursor position before FN is
794 This is called by most of the virtual-cursor copying commands to find
795 out how much to copy."
799 (set-buffer (overlay-buffer vcursor-overlay
))
800 (let ((start (goto-char (overlay-start vcursor-overlay
))))
801 (- (progn (apply fn args
) (point)) start
)))
804 ;; Make sure the virtual cursor is active. Unless arg is non-nil,
805 ;; report an error if it is not.
806 (defun vcursor-check (&optional arg
)
808 ((and (overlayp vcursor-overlay
) (overlay-start vcursor-overlay
))
811 (t (error "The virtual cursor is not active now")))
814 (defun vcursor-disable (&optional arg
)
815 "Disable the virtual cursor.
816 Next time you use it, it will start from point.
818 With a positive prefix ARG, the first window in cyclic order
819 displaying the virtual cursor (or which was recently displaying the
820 virutal cursor) will be deleted unless it's the selected
823 With a negative prefix argument, enable the virtual cursor: make it
824 active at the same point as the real cursor.
826 Copying mode is always turned off: the next use of the vcursor will
827 not copy text until you turn it on again."
830 (if (overlayp vcursor-overlay
)
832 (delete-overlay vcursor-overlay
)
833 (setq vcursor-overlay nil
)))
835 ((not (vcursor-find-window t
)))
836 ((or (not arg
) (< (prefix-numeric-value arg
) 0)))
837 ((delete-window vcursor-window
)))
839 ((and arg
(< (prefix-numeric-value arg
) 0))
840 (vcursor-move (point))
841 (setq vcursor-window
(selected-window)))
842 (vcursor-use-vcursor-map (vcursor-toggle-vcursor-map 0)))
843 (setq vcursor-copy-flag nil
)
846 (defun vcursor-other-window (n &optional all-frames
)
847 "Activate the virtual cursor in another window.
848 This is the next window cylically after one currently showing the
849 virtual cursor, or else after the current selected window. If there
850 is no other window, the current window is split.
852 Arguments N and optional ALL-FRAMES are the same as with other-window.
853 ALL-FRAMES is also used to decide whether to split the window."
856 (if (if (fboundp 'oemacs-version
)
858 (one-window-p nil all-frames
))
859 (display-buffer (current-buffer) t
))
861 (save-window-excursion
862 ;; We don't use fancy vcursor-find-window trickery, since we're
863 ;; quite happy to have the vcursor cycle back into the current
865 (let ((sw (selected-window))
866 (win (vcursor-find-window nil nil
(not all-frames
))))
867 (if win
(select-window win
))
868 ;; else start from here
869 (other-window n all-frames
)
870 (vcursor-disable -
1))))
873 ;; vcursor-compare-windows is copied from compare-w.el with only
874 ;; minor modifications; these are too bound up with the function
875 ;; to make it really useful to call compare-windows itself.
876 (defun vcursor-compare-windows (&optional ignore-whitespace
)
877 "Compare text in current window with text in window with vcursor.
878 Compares the text starting at point in the current window and at the
879 vcursor position in the other window, moving over text in each one as
882 A prefix argument, if any, means ignore changes in whitespace.
883 The variable `compare-windows-whitespace' controls how whitespace is skipped.
884 If `compare-ignore-case' is non-nil, changes in case are also ignored."
886 ;; (vcursor-window-funcall 'compare-windows arg)
888 (let* (p1 p2 maxp1 maxp2 b1 b2 w2
892 (skip-whitespace (if ignore-whitespace
893 compare-windows-whitespace
)))
894 (setq p1
(point) b1
(current-buffer))
895 (setq w2
(vcursor-find-window t t
))
896 (if (or (eq w2
(selected-window)) (not w2
))
897 (error "No other window with vcursor"))
900 (setq p2
(point) b2
(current-buffer)))
902 (setq maxp1
(point-max))
905 (setq maxp2
(point-max)))
910 ;; if interrupted, show how far we've gotten
914 ;; If both buffers have whitespace next to point,
915 ;; optionally skip over it.
919 (let (p1a p2a w1 w2 result1 result2
)
921 (if (stringp skip-whitespace
)
922 (compare-windows-skip-whitespace opoint1
)
923 (funcall skip-whitespace opoint1
)))
928 (if (stringp skip-whitespace
)
929 (compare-windows-skip-whitespace opoint2
)
930 (funcall skip-whitespace opoint2
)))
932 (if (or (stringp skip-whitespace
)
933 (and result1 result2
(eq result1 result2
)))
937 ;; Try advancing comparing 1000 chars at a time.
938 ;; When that fails, go 500 chars at a time, and so on.
941 (case-fold-search compare-ignore-case
))
944 ;; Try comparing SIZE chars at a time, repeatedly, till that fails.
946 (setq size
(min size
(- maxp1 p1
) (- maxp2 p2
)))
949 (= 0 (compare-buffer-substrings b2 p2
(+ size p2
)
950 b1 p1
(+ size p1
)))))
952 (setq p1
(+ p1 size
) p2
(+ p2 size
)
954 ;; If SIZE chars don't match, try fewer.
955 (setq size
(/ size
2)))))
959 (if (= (point) opoint1
)
963 (defun vcursor-next-line (arg)
964 "Move the virtual cursor forward ARG lines."
965 ;; This is next-line rewritten for the vcursor. Maybe it would
966 ;; be easier simply to rewrite line-move.
968 (let (temporary-goal-column opoint text
)
971 (setq temporary-goal-column
972 (if (or (eq last-command
'vcursor-next-line
)
973 (eq last-command
'vcursor-previous-line
))
975 (setq last-command
'next-line
) ; trick line-move
976 vcursor-temp-goal-column
)
977 (if (and track-eol
(eolp)
978 (or (not (bolp)) (eq last-command
'end-of-line
)))
983 (and (eq opoint
(point-max)) (eq opoint
(point))
984 (signal 'end-of-buffer nil
))
985 (if vcursor-copy-flag
(setq text
(buffer-substring opoint
(point))))
986 (vcursor-move (point))
987 (setq vcursor-temp-goal-column temporary-goal-column
988 vcursor-last-command t
))
989 (if text
(vcursor-insert text
)))
992 (defun vcursor-previous-line (arg)
993 "Move the virtual cursor back ARG lines."
995 (vcursor-next-line (- arg
))
998 (defun vcursor-forward-char (arg)
999 "Move the virtual cursor forward ARG characters."
1001 (vcursor-relative-move 'forward-char arg
)
1004 (defun vcursor-backward-char (arg)
1005 "Move the virtual cursor backward ARG characters."
1007 (vcursor-relative-move 'backward-char arg
)
1010 (defun vcursor-forward-word (arg)
1011 "Move the virtual cursor forward ARG words."
1013 (vcursor-relative-move 'forward-word arg
)
1016 (defun vcursor-backward-word (arg)
1017 "Move the virtual cursor backward ARG words."
1019 (vcursor-relative-move 'backward-word arg
)
1022 (defun vcursor-beginning-of-line (arg)
1023 "Move the virtual cursor to beginning of its current line.
1024 ARG is as for `beginning-of-line'."
1026 (vcursor-relative-move 'beginning-of-line
1027 (if arg
(prefix-numeric-value arg
)))
1030 (defun vcursor-end-of-line (arg)
1031 "Move the virtual cursor to end of its current line.
1032 ARG is as for `end-of-line'."
1034 (vcursor-relative-move 'end-of-line
1035 (if arg
(prefix-numeric-value arg
)))
1038 (defun vcursor-beginning-of-buffer (&optional arg
)
1039 "Move the virtual cursor to the beginning of its buffer.
1040 ARG is as for beginning-of-buffer."
1042 (vcursor-relative-move
1044 (goto-char (if arg
(/ (* arg
(- (point-max) (point-min))) 10)
1046 (if arg
(prefix-numeric-value arg
)))
1049 (defun vcursor-end-of-buffer (&optional arg
)
1050 "Move the virtual cursor to the end of its buffer.
1051 ARG is as for end-of-buffer.
1053 Actually, the vcursor is moved to the second from last character or it
1054 would be invisible."
1056 (vcursor-relative-move
1058 (goto-char (if arg
(- (point-max)
1059 (/ (* arg
(- (point-max) (point-min))) 10))
1061 (if arg
(prefix-numeric-value arg
)))
1064 (defun vcursor-execute-command (cmd)
1065 "Execute COMMAND for the virtual cursor.
1066 COMMAND is called interactively. Not all commands (in fact, only a
1067 small subset) are useful."
1068 (interactive "CCommand: ")
1069 (vcursor-window-funcall (list cmd
))
1072 (defun vcursor-execute-key ()
1073 "Read a key sequence and execute the bound command for the virtual cursor.
1074 The key sequence is read at the vcursor location. The command found
1075 is called interactively, so prefix argument etc. are usable."
1079 ;; We'd like to avoid the display changing when we locate
1080 ;; to the vcursor position and read a key sequence.
1081 (vcursor-find-window (not (vcursor-check t
)) t
)
1082 (save-window-excursion
1083 (select-window vcursor-window
)
1085 (setq cmd
(key-binding (read-key-sequence "Key sequence: ")))))
1086 (vcursor-window-funcall (list cmd
)))
1089 (defun vcursor-copy (arg)
1090 "Copy ARG characters from the virtual cursor position to point."
1095 (set-buffer (overlay-buffer vcursor-overlay
))
1096 (let* ((ostart (overlay-start vcursor-overlay
))
1097 (end (+ ostart arg
)))
1099 (buffer-substring ostart end
)
1100 (vcursor-move end
)))))
1101 (setq vcursor-last-command t
)
1104 (defun vcursor-copy-word (arg)
1105 "Copy ARG words from the virtual cursor position to point."
1107 (vcursor-copy (vcursor-get-char-count 'forward-word arg
))
1110 (defun vcursor-copy-line (arg)
1111 "Copy up to ARGth line after virtual cursor position.
1112 With no argument, copy to the end of the current line.
1114 Behaviour with regard to newlines is similar (but not identical) to
1115 `kill-line'; the main difference is that whitespace at the end of the
1116 line is treated like ordinary characters."
1119 (let* ((num (prefix-numeric-value arg
))
1120 (count (vcursor-get-char-count 'end-of-line num
)))
1121 (vcursor-copy (if (or (= count
0) arg
) (1+ count
) count
)))
1124 (defun vcursor-toggle-vcursor-map (&optional force noredisp
)
1125 "Toggle the state of the vcursor key map.
1126 When on, the keys defined in it are mapped directly on top of the main
1127 keymap, allowing you to move the vcursor with ordinary motion keys.
1128 An indication \"!VC\" appears in the mode list. The effect is
1129 local to the current buffer.
1130 With prefix FORCE, turn on, or off if it is 0.
1131 With NOREDISP, don't force redisplay.
1132 Disabling the vcursor automatically turns this off."
1134 (let ((new (cond ((not force
) (not vcursor-use-vcursor-map
))
1137 (or (eq new vcursor-use-vcursor-map
)
1139 (setq vcursor-use-vcursor-map new
)
1140 (or (assq 'vcursor-use-vcursor-map minor-mode-map-alist
)
1141 (setq minor-mode-map-alist
1142 (cons (cons 'vcursor-use-vcursor-map vcursor-map
)
1143 minor-mode-map-alist
)))
1144 (or (assq 'vcursor-use-vcursor-map minor-mode-alist
)
1145 (setq minor-mode-alist
1146 (cons (list 'vcursor-use-vcursor-map
" !VC")
1148 (or noredisp
(redraw-display)))))
1151 (defun vcursor-post-command ()
1152 (and vcursor-auto-disable
(not vcursor-last-command
)
1154 (if (eq vcursor-auto-disable t
)
1156 (vcursor-toggle-copy -
1 t
)))
1157 (setq vcursor-last-command nil
)
1160 (add-hook 'post-command-hook
'vcursor-post-command
)
1164 ;;; vcursor.el ends here