lisp/window.el

   1 ;;; window.el --- GNU Emacs window commands aside from those written in C
   2
   3 ;; Copyright (C) 1985, 1989, 1992, 1993, 1994, 2000, 2001, 2002, 2004, 2005
   4 ;;  Free Software Foundation, Inc.
   5
   6 ;; Maintainer: FSF
   7 ;; Keywords: internal
   8
   9 ;; This file is part of GNU Emacs.
  10
  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)
  14 ;; any later version.
  15
  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.
  20
  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.
  25
  26 ;;; Commentary:
  27
  28 ;; Window tree functions.
  29
  30 ;;; Code:
  31
  32 (defmacro save-selected-window (&rest body)
  33   "Execute BODY, then select the window that was selected before BODY.
  34 Also restore the selected window of each frame as it was at the start
  35 of this construct.
  36 However, if a window has become dead, don't get an error,
  37 just refrain from reselecting it.
  38 Return the value of the last form in BODY."
  39   `(let ((save-selected-window-window (selected-window))
  40          ;; It is necessary to save all of these, because calling
  41          ;; select-window changes frame-selected-window for whatever
  42          ;; frame that window is in.
  43          (save-selected-window-alist
  44           (mapcar (lambda (frame) (list frame (frame-selected-window frame)))
  45                   (frame-list))))
  46      (unwind-protect
  47          (progn ,@body)
  48        (dolist (elt save-selected-window-alist)
  49          (and (frame-live-p (car elt))
  50               (window-live-p (cadr elt))
  51               (set-frame-selected-window (car elt) (cadr elt))))
  52        (if (window-live-p save-selected-window-window)
  53            (select-window save-selected-window-window)))))
  54
  55 (defun window-body-height (&optional window)
  56   "Return number of lines in window WINDOW for actual buffer text.
  57 This does not include the mode line (if any) or the header line (if any)."
  58   (or window (setq window (selected-window)))
  59   (if (window-minibuffer-p window)
  60       (window-height window)
  61     (with-current-buffer (window-buffer window)
  62       (max 1 (- (window-height window)
  63                 (if mode-line-format 1 0)
  64                 (if header-line-format 1 0))))))
  65
  66 (defun one-window-p (&optional nomini all-frames)
  67   "Return non-nil if the selected window is the only window.
  68 Optional arg NOMINI non-nil means don't count the minibuffer
  69 even if it is active.  Otherwise, the minibuffer is counted
  70 when it is active.
  71
  72 The optional arg ALL-FRAMES t means count windows on all frames.
  73 If it is `visible', count windows on all visible frames.
  74 ALL-FRAMES nil or omitted means count only the selected frame,
  75 plus the minibuffer it uses (which may be on another frame).
  76 ALL-FRAMES 0 means count all windows in all visible or iconified frames.
  77 If ALL-FRAMES is anything else, count only the selected frame."
  78   (let ((base-window (selected-window)))
  79     (if (and nomini (eq base-window (minibuffer-window)))
  80         (setq base-window (next-window base-window)))
  81     (eq base-window
  82         (next-window base-window (if nomini 'arg) all-frames))))
  83
  84 (defun window-current-scroll-bars (&optional window)
  85   "Return the current scroll-bar settings in window WINDOW.
  86 Value is a cons (VERTICAL . HORISONTAL) where VERTICAL specifies the
  87 current location of the vertical scroll-bars (left, right, or nil),
  88 and HORISONTAL specifies the current location of the horisontal scroll
  89 bars (top, bottom, or nil)."
  90   (let ((vert (nth 2 (window-scroll-bars window)))
  91         (hor nil))
  92     (when (or (eq vert t) (eq hor t))
  93       (let ((fcsb (frame-current-scroll-bars
  94                    (window-frame (or window (selected-window))))))
  95         (if (eq vert t)
  96             (setq vert (car fcsb)))
  97         (if (eq hor t)
  98             (setq hor (cdr fcsb)))))
  99     (cons vert hor)))
 100
 101 (defun walk-windows (proc &optional minibuf all-frames)
 102   "Cycle through all visible windows, calling PROC for each one.
 103 PROC is called with a window as argument.
 104
 105 Optional second arg MINIBUF t means count the minibuffer window even
 106 if not active.  MINIBUF nil or omitted means count the minibuffer iff
 107 it is active.  MINIBUF neither t nor nil means not to count the
 108 minibuffer even if it is active.
 109
 110 Several frames may share a single minibuffer; if the minibuffer
 111 counts, all windows on all frames that share that minibuffer count
 112 too.  Therefore, if you are using a separate minibuffer frame
 113 and the minibuffer is active and MINIBUF says it counts,
 114 `walk-windows' includes the windows in the frame from which you
 115 entered the minibuffer, as well as the minibuffer window.
 116
 117 ALL-FRAMES is the optional third argument.
 118 ALL-FRAMES nil or omitted means cycle within the frames as specified above.
 119 ALL-FRAMES = `visible' means include windows on all visible frames.
 120 ALL-FRAMES = 0 means include windows on all visible and iconified frames.
 121 ALL-FRAMES = t means include windows on all frames including invisible frames.
 122 If ALL-FRAMES is a frame, it means include windows on that frame.
 123 Anything else means restrict to the selected frame."
 124   ;; If we start from the minibuffer window, don't fail to come back to it.
 125   (if (window-minibuffer-p (selected-window))
 126       (setq minibuf t))
 127   (save-selected-window
 128     (if (framep all-frames)
 129         (select-window (frame-first-window all-frames)))
 130     (let* (walk-windows-already-seen
 131            (walk-windows-current (selected-window)))
 132       (while (progn
 133                (setq walk-windows-current
 134                      (next-window walk-windows-current minibuf all-frames))
 135                (not (memq walk-windows-current walk-windows-already-seen)))
 136         (setq walk-windows-already-seen
 137               (cons walk-windows-current walk-windows-already-seen))
 138         (funcall proc walk-windows-current)))))
 139
 140 (defun get-window-with-predicate (predicate &optional minibuf
 141                                             all-frames default)
 142   "Return a window satisfying PREDICATE.
 143
 144 This function cycles through all visible windows using `walk-windows',
 145 calling PREDICATE on each one.  PREDICATE is called with a window as
 146 argument.  The first window for which PREDICATE returns a non-nil
 147 value is returned.  If no window satisfies PREDICATE, DEFAULT is
 148 returned.
 149
 150 Optional second arg MINIBUF t means count the minibuffer window even
 151 if not active.  MINIBUF nil or omitted means count the minibuffer iff
 152 it is active.  MINIBUF neither t nor nil means not to count the
 153 minibuffer even if it is active.
 154
 155 Several frames may share a single minibuffer; if the minibuffer
 156 counts, all windows on all frames that share that minibuffer count
 157 too.  Therefore, if you are using a separate minibuffer frame
 158 and the minibuffer is active and MINIBUF says it counts,
 159 `walk-windows' includes the windows in the frame from which you
 160 entered the minibuffer, as well as the minibuffer window.
 161
 162 ALL-FRAMES is the optional third argument.
 163 ALL-FRAMES nil or omitted means cycle within the frames as specified above.
 164 ALL-FRAMES = `visible' means include windows on all visible frames.
 165 ALL-FRAMES = 0 means include windows on all visible and iconified frames.
 166 ALL-FRAMES = t means include windows on all frames including invisible frames.
 167 If ALL-FRAMES is a frame, it means include windows on that frame.
 168 Anything else means restrict to the selected frame."
 169   (catch 'found
 170     (walk-windows #'(lambda (window)
 171                       (when (funcall predicate window)
 172                         (throw 'found window)))
 173                   minibuf all-frames)
 174     default))
 175
 176 (defalias 'some-window 'get-window-with-predicate)
 177
 178 (defun minibuffer-window-active-p (window)
 179   "Return t if WINDOW (a minibuffer window) is now active."
 180   (eq window (active-minibuffer-window)))
 181 \f
 182 (defun count-windows (&optional minibuf)
 183    "Return the number of visible windows.
 184 This counts the windows in the selected frame and (if the minibuffer is
 185 to be counted) its minibuffer frame (if that's not the same frame).
 186 The optional arg MINIBUF non-nil means count the minibuffer
 187 even if it is inactive."
 188    (let ((count 0))
 189      (walk-windows (function (lambda (w)
 190                                (setq count (+ count 1))))
 191                    minibuf)
 192      count))
 193
 194 (defun window-safely-shrinkable-p (&optional window)
 195   "Non-nil if the WINDOW can be shrunk without shrinking other windows.
 196 If WINDOW is nil or omitted, it defaults to the currently selected window."
 197   (with-selected-window (or window (selected-window))
 198     (let ((edges (window-edges)))
 199       (or (= (nth 2 edges) (nth 2 (window-edges (previous-window))))
 200           (= (nth 0 edges) (nth 0 (window-edges (next-window))))))))
 201
 202
 203 (defun balance-windows ()
 204   "Make all visible windows the same height (approximately)."
 205   (interactive)
 206   (let ((count -1) levels newsizes level-size
 207         ;; Don't count the lines that are above the uppermost windows.
 208         ;; (These are the menu bar lines, if any.)
 209         (mbl (nth 1 (window-edges (frame-first-window (selected-frame)))))
 210         (last-window (previous-window (frame-first-window (selected-frame))))
 211         ;; Don't count the lines that are past the lowest main window.
 212         total)
 213     ;; Bottom edge of last window determines what size we have to work with.
 214     (setq total
 215           (+ (window-height last-window)
 216              (nth 1 (window-edges last-window))))
 217
 218     ;; Find all the different vpos's at which windows start,
 219     ;; then count them.  But ignore levels that differ by only 1.
 220     (let (tops (prev-top -2))
 221       (walk-windows (function (lambda (w)
 222                                 (setq tops (cons (nth 1 (window-edges w))
 223                                                  tops))))
 224                     'nomini)
 225       (setq tops (sort tops '<))
 226       (while tops
 227         (if (> (car tops) (1+ prev-top))
 228             (setq prev-top (car tops)
 229                   count (1+ count)))
 230         (setq levels (cons (cons (car tops) count) levels))
 231         (setq tops (cdr tops)))
 232       (setq count (1+ count)))
 233     ;; Subdivide the frame into desired number of vertical levels.
 234     (setq level-size (/ (- total mbl) count))
 235     (save-selected-window
 236       ;; Set up NEWSIZES to map windows to their desired sizes.
 237       ;; If a window ends at the bottom level, don't include
 238       ;; it in NEWSIZES.  Those windows get the right sizes
 239       ;; by adjusting the ones above them.
 240       (walk-windows (function
 241                      (lambda (w)
 242                        (let ((newtop (cdr (assq (nth 1 (window-edges w))
 243                                                 levels)))
 244                              (newbot (cdr (assq (+ (window-height w)
 245                                                    (nth 1 (window-edges w)))
 246                                                 levels))))
 247                          (if newbot
 248                              (setq newsizes
 249                                    (cons (cons w (* level-size (- newbot newtop)))
 250                                          newsizes))))))
 251                     'nomini)
 252       ;; Make walk-windows start with the topmost window.
 253       (select-window (previous-window (frame-first-window (selected-frame))))
 254       (let (done (count 0))
 255         ;; Give each window its precomputed size, or at least try.
 256         ;; Keep trying until they all get the intended sizes,
 257         ;; but not more than 3 times (to prevent infinite loop).
 258         (while (and (not done) (< count 3))
 259           (setq done t)
 260           (setq count (1+ count))
 261           (walk-windows (function (lambda (w)
 262                                     (select-window w)
 263                                     (let ((newsize (cdr (assq w newsizes))))
 264                                       (when newsize
 265                                         (enlarge-window (- newsize
 266                                                            (window-height))
 267                                                         nil t)
 268                                         (unless (= (window-height) newsize)
 269                                           (setq done nil))))))
 270                         'nomini))))))
 271 \f
 272 ;; I think this should be the default; I think people will prefer it--rms.
 273 (defcustom split-window-keep-point t
 274   "*If non-nil, \\[split-window-vertically] keeps the original point \
 275 in both children.
 276 This is often more convenient for editing.
 277 If nil, adjust point in each of the two windows to minimize redisplay.
 278 This is convenient on slow terminals, but point can move strangely.
 279
 280 This option applies only to `split-window-vertically' and
 281 functions that call it.  `split-window' always keeps the original
 282 point in both children,"
 283   :type 'boolean
 284   :group 'windows)
 285
 286 (defun split-window-vertically (&optional arg)
 287   "Split current window into two windows, one above the other.
 288 The uppermost window gets ARG lines and the other gets the rest.
 289 Negative ARG means select the size of the lowermost window instead.
 290 With no argument, split equally or close to it.
 291 Both windows display the same buffer now current.
 292
 293 If the variable `split-window-keep-point' is non-nil, both new windows
 294 will get the same value of point as the current window.  This is often
 295 more convenient for editing.  The upper window is the selected window.
 296
 297 Otherwise, we choose window starts so as to minimize the amount of
 298 redisplay; this is convenient on slow terminals.  The new selected
 299 window is the one that the current value of point appears in.  The
 300 value of point can change if the text around point is hidden by the
 301 new mode line.
 302
 303 Regardless of the value of `split-window-keep-point', the upper
 304 window is the original one and the return value is the new, lower
 305 window."
 306   (interactive "P")
 307   (let ((old-w (selected-window))
 308         (old-point (point))
 309         (size (and arg (prefix-numeric-value arg)))
 310         (window-full-p nil)
 311         new-w bottom switch moved)
 312     (and size (< size 0) (setq size (+ (window-height) size)))
 313     (setq new-w (split-window nil size))
 314     (or split-window-keep-point
 315         (progn
 316           (save-excursion
 317             (set-buffer (window-buffer))
 318             (goto-char (window-start))
 319             (setq moved (vertical-motion (window-height)))
 320             (set-window-start new-w (point))
 321             (if (> (point) (window-point new-w))
 322                 (set-window-point new-w (point)))
 323             (and (= moved (window-height))
 324                  (progn
 325                    (setq window-full-p t)
 326                    (vertical-motion -1)))
 327             (setq bottom (point)))
 328           (and window-full-p
 329                (<= bottom (point))
 330                (set-window-point old-w (1- bottom)))
 331           (and window-full-p
 332                (<= (window-start new-w) old-point)
 333                (progn
 334                  (set-window-point new-w old-point)
 335                  (select-window new-w)))))
 336     (split-window-save-restore-data new-w old-w)))
 337
 338 ;; This is to avoid compiler warnings.
 339 (defvar view-return-to-alist)
 340
 341 (defun split-window-save-restore-data (new-w old-w)
 342   (with-current-buffer (window-buffer)
 343     (if view-mode
 344         (let ((old-info (assq old-w view-return-to-alist)))
 345           (if old-info
 346               (push (cons new-w (cons (car (cdr old-info)) t))
 347                     view-return-to-alist))))
 348     new-w))
 349
 350 (defun split-window-horizontally (&optional arg)
 351   "Split current window into two windows side by side.
 352 This window becomes the leftmost of the two, and gets ARG columns.
 353 Negative ARG means select the size of the rightmost window instead.
 354 The argument includes the width of the window's scroll bar; if there
 355 are no scroll bars, it includes the width of the divider column
 356 to the window's right, if any.  No ARG means split equally.
 357
 358 The original, leftmost window remains selected.
 359 The return value is the new, rightmost window."
 360   (interactive "P")
 361   (let ((old-w (selected-window))
 362         (size (and arg (prefix-numeric-value arg))))
 363     (and size (< size 0)
 364          (setq size (+ (window-width) size)))
 365     (split-window-save-restore-data (split-window nil size t) old-w)))
 366
 367 \f
 368 (defun set-window-text-height (window height)
 369   "Sets the height in lines of the text display area of WINDOW to HEIGHT.
 370 This doesn't include the mode-line (or header-line if any) or any
 371 partial-height lines in the text display area.
 372
 373 If WINDOW is nil, the selected window is used.
 374
 375 Note that the current implementation of this function cannot always set
 376 the height exactly, but attempts to be conservative, by allocating more
 377 lines than are actually needed in the case where some error may be present."
 378   (let ((delta (- height (window-text-height window))))
 379     (unless (zerop delta)
 380       (let ((window-min-height 1))
 381         (if (and window (not (eq window (selected-window))))
 382             (save-selected-window
 383               (select-window window)
 384               (enlarge-window delta))
 385           (enlarge-window delta))))))
 386
 387 \f
 388 (defun enlarge-window-horizontally (arg)
 389   "Make current window ARG columns wider."
 390   (interactive "p")
 391   (enlarge-window arg t))
 392
 393 (defun shrink-window-horizontally (arg)
 394   "Make current window ARG columns narrower."
 395   (interactive "p")
 396   (shrink-window arg t))
 397
 398 (defun window-buffer-height (window)
 399   "Return the height (in screen lines) of the buffer that WINDOW is displaying."
 400   (save-excursion
 401     (set-buffer (window-buffer window))
 402     (goto-char (point-min))
 403     (let ((ignore-final-newline
 404            ;; If buffer ends with a newline, ignore it when counting height
 405            ;; unless point is after it.
 406            (and (not (eobp)) (eq ?\n (char-after (1- (point-max)))))))
 407       (+ 1 (nth 2 (compute-motion (point-min)
 408                                   '(0 . 0)
 409                                   (- (point-max) (if ignore-final-newline 1 0))
 410                                   (cons 0 100000000)
 411                                   nil
 412                                   nil
 413                                   window))))))
 414
 415 (defun count-screen-lines (&optional beg end count-final-newline window)
 416   "Return the number of screen lines in the region.
 417 The number of screen lines may be different from the number of actual lines,
 418 due to line breaking, display table, etc.
 419
 420 Optional arguments BEG and END default to `point-min' and `point-max'
 421 respectively.
 422
 423 If region ends with a newline, ignore it unless optional third argument
 424 COUNT-FINAL-NEWLINE is non-nil.
 425
 426 The optional fourth argument WINDOW specifies the window used for obtaining
 427 parameters such as width, horizontal scrolling, and so on.  The default is
 428 to use the selected window's parameters.
 429
 430 Like `vertical-motion', `count-screen-lines' always uses the current buffer,
 431 regardless of which buffer is displayed in WINDOW.  This makes possible to use
 432 `count-screen-lines' in any buffer, whether or not it is currently displayed
 433 in some window."
 434   (unless beg
 435     (setq beg (point-min)))
 436   (unless end
 437     (setq end (point-max)))
 438   (if (= beg end)
 439       0
 440     (save-excursion
 441       (save-restriction
 442         (widen)
 443         (narrow-to-region (min beg end)
 444                           (if (and (not count-final-newline)
 445                                    (= ?\n (char-before (max beg end))))
 446                               (1- (max beg end))
 447                             (max beg end)))
 448         (goto-char (point-min))
 449         (1+ (vertical-motion (buffer-size) window))))))
 450
 451 (defun fit-window-to-buffer (&optional window max-height min-height)
 452   "Make WINDOW the right size to display its contents exactly.
 453 If WINDOW is omitted or nil, it defaults to the selected window.
 454 If the optional argument MAX-HEIGHT is supplied, it is the maximum height
 455   the window is allowed to be, defaulting to the frame height.
 456 If the optional argument MIN-HEIGHT is supplied, it is the minimum
 457   height the window is allowed to be, defaulting to `window-min-height'.
 458
 459 The heights in MAX-HEIGHT and MIN-HEIGHT include the mode-line and/or
 460 header-line."
 461   (interactive)
 462
 463   (when (null window)
 464     (setq window (selected-window)))
 465   (when (null max-height)
 466     (setq max-height (frame-height (window-frame window))))
 467
 468   (let* ((buf
 469           ;; Buffer that is displayed in WINDOW
 470           (window-buffer window))
 471          (window-height
 472           ;; The current height of WINDOW
 473           (window-height window))
 474          (desired-height
 475           ;; The height necessary to show the buffer displayed by WINDOW
 476           ;; (`count-screen-lines' always works on the current buffer).
 477           (with-current-buffer buf
 478             (+ (count-screen-lines)
 479                ;; If the buffer is empty, (count-screen-lines) is
 480                ;; zero.  But, even in that case, we need one text line
 481                ;; for cursor.
 482                (if (= (point-min) (point-max))
 483                    1 0)
 484                ;; For non-minibuffers, count the mode-line, if any
 485                (if (and (not (window-minibuffer-p window))
 486                         mode-line-format)
 487                    1 0)
 488                ;; Count the header-line, if any
 489                (if header-line-format 1 0))))
 490          (delta
 491           ;; Calculate how much the window height has to change to show
 492           ;; desired-height lines, constrained by MIN-HEIGHT and MAX-HEIGHT.
 493           (- (max (min desired-height max-height)
 494                   (or min-height window-min-height))
 495              window-height))
 496          ;; We do our own height checking, so avoid any restrictions due to
 497          ;; window-min-height.
 498          (window-min-height 1))
 499
 500     ;; Don't try to redisplay with the cursor at the end
 501     ;; on its own line--that would force a scroll and spoil things.
 502     (when (with-current-buffer buf
 503             (and (eobp) (bolp) (not (bobp))))
 504       (set-window-point window (1- (window-point window))))
 505
 506     (save-selected-window
 507       (select-window window)
 508
 509       ;; Adjust WINDOW to the nominally correct size (which may actually
 510       ;; be slightly off because of variable height text, etc).
 511       (unless (zerop delta)
 512         (enlarge-window delta))
 513
 514       ;; Check if the last line is surely fully visible.  If not,
 515       ;; enlarge the window.
 516       (let ((end (with-current-buffer buf
 517                    (save-excursion
 518                      (goto-char (point-max))
 519                      (when (and (bolp) (not (bobp)))
 520                        ;; Don't include final newline
 521                        (backward-char 1))
 522                      (when truncate-lines
 523                        ;; If line-wrapping is turned off, test the
 524                        ;; beginning of the last line for visibility
 525                        ;; instead of the end, as the end of the line
 526                        ;; could be invisible by virtue of extending past
 527                        ;; the edge of the window.
 528                        (forward-line 0))
 529                      (point)))))
 530         (set-window-vscroll window 0)
 531         (while (and (< desired-height max-height)
 532                     (= desired-height (window-height window))
 533                     (not (pos-visible-in-window-p end window)))
 534           (enlarge-window 1)
 535           (setq desired-height (1+ desired-height)))))))
 536
 537 (defun shrink-window-if-larger-than-buffer (&optional window)
 538   "Shrink the WINDOW to be as small as possible to display its contents.
 539 If WINDOW is omitted or nil, it defaults to the selected window.
 540 Do not shrink to less than `window-min-height' lines.
 541 Do nothing if the buffer contains more lines than the present window height,
 542 or if some of the window's contents are scrolled out of view,
 543 or if shrinking this window would also shrink another window.
 544 or if the window is the only window of its frame.
 545 Return non-nil if the window was shrunk."
 546   (interactive)
 547   (when (null window)
 548     (setq window (selected-window)))
 549   (let* ((frame (window-frame window))
 550          (mini (frame-parameter frame 'minibuffer))
 551          (edges (window-edges window)))
 552     (if (and (not (eq window (frame-root-window frame)))
 553              (window-safely-shrinkable-p)
 554              (pos-visible-in-window-p (point-min) window)
 555              (not (eq mini 'only))
 556              (or (not mini)
 557                  (let ((mini-window (minibuffer-window frame)))
 558                    (or (null mini-window)
 559                        (not (eq frame (window-frame mini-window)))
 560                        (< (nth 3 edges)
 561                           (nth 1 (window-edges mini-window)))
 562                        (> (nth 1 edges)
 563                           (frame-parameter frame 'menu-bar-lines))))))
 564         (fit-window-to-buffer window (window-height window)))))
 565
 566 (defun kill-buffer-and-window ()
 567   "Kill the current buffer and delete the selected window."
 568   (interactive)
 569   (let ((window-to-delete (selected-window))
 570         (delete-window-hook (lambda ()
 571                               (condition-case nil
 572                                   (delete-window)
 573                                 (error nil)))))
 574     (add-hook 'kill-buffer-hook delete-window-hook t t)
 575     (if (kill-buffer (current-buffer))
 576         ;; If `delete-window' failed before, we rerun it to regenerate
 577         ;; the error so it can be seen in the minibuffer.
 578         (when (eq (selected-window) window-to-delete)
 579           (delete-window))
 580       (remove-hook 'kill-buffer-hook delete-window-hook t))))
 581
 582 (defun quit-window (&optional kill window)
 583   "Quit the current buffer.  Bury it, and maybe delete the selected frame.
 584 \(The frame is deleted if it is contains a dedicated window for the buffer.)
 585 With a prefix argument, kill the buffer instead.
 586
 587 Noninteractively, if KILL is non-nil, then kill the current buffer,
 588 otherwise bury it.
 589
 590 If WINDOW is non-nil, it specifies a window; we delete that window,
 591 and the buffer that is killed or buried is the one in that window."
 592   (interactive "P")
 593   (let ((buffer (window-buffer window))
 594         (frame (window-frame (or window (selected-window))))
 595         (window-solitary
 596          (save-selected-window
 597            (if window
 598                (select-window window))
 599            (one-window-p t)))
 600         window-handled)
 601
 602     (save-selected-window
 603       (if window
 604           (select-window window))
 605       (or (window-minibuffer-p)
 606           (window-dedicated-p (selected-window))
 607           (switch-to-buffer (other-buffer))))
 608
 609     ;; Get rid of the frame, if it has just one dedicated window
 610     ;; and other visible frames exist.
 611     (and (or (window-minibuffer-p) (window-dedicated-p window))
 612          (delq frame (visible-frame-list))
 613          window-solitary
 614          (if (and (eq default-minibuffer-frame frame)
 615                   (= 1 (length (minibuffer-frame-list))))
 616              (setq window nil)
 617            (delete-frame frame)
 618            (setq window-handled t)))
 619
 620     ;; Deal with the buffer.
 621     (if kill
 622         (kill-buffer buffer)
 623       (bury-buffer buffer))
 624
 625     ;; Maybe get rid of the window.
 626     (and window (not window-handled) (not window-solitary)
 627          (delete-window window))))
 628
 629 (defun handle-select-window (event)
 630   "Handle select-window events."
 631   (interactive "e")
 632   (let ((window (posn-window (event-start event))))
 633     (if (and (window-live-p window)
 634              ;; Don't switch if we're currently in the minibuffer.
 635              ;; This tries to work around problems where the minibuffer gets
 636              ;; unselected unexpectedly, and where you then have to move
 637              ;; your mouse all the way down to the minibuffer to select it.
 638              (not (window-minibuffer-p (selected-window)))
 639              ;; Don't switch to a minibuffer window unless it's active.
 640              (or (not (window-minibuffer-p window))
 641                  (minibuffer-window-active-p window)))
 642         (select-window window))))
 643
 644 (define-key ctl-x-map "2" 'split-window-vertically)
 645 (define-key ctl-x-map "3" 'split-window-horizontally)
 646 (define-key ctl-x-map "}" 'enlarge-window-horizontally)
 647 (define-key ctl-x-map "{" 'shrink-window-horizontally)
 648 (define-key ctl-x-map "-" 'shrink-window-if-larger-than-buffer)
 649 (define-key ctl-x-map "+" 'balance-windows)
 650 (define-key ctl-x-4-map "0" 'kill-buffer-and-window)
 651
 652 ;; arch-tag: b508dfcc-c353-4c37-89fa-e773fe10cea9
 653 ;;; window.el ends here