-;;; window.el --- GNU Emacs window commands aside from those written in C\r
-\r
-;; Copyright (C) 1985, 1989, 1992, 1993, 1994, 2000, 2001, 2002,\r
-;; 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.\r
-\r
-;; Maintainer: FSF\r
-;; Keywords: internal\r
-\r
-;; This file is part of GNU Emacs.\r
-\r
-;; GNU Emacs is free software: you can redistribute it and/or modify\r
-;; it under the terms of the GNU General Public License as published by\r
-;; the Free Software Foundation, either version 3 of the License, or\r
-;; (at your option) any later version.\r
-\r
-;; GNU Emacs is distributed in the hope that it will be useful,\r
-;; but WITHOUT ANY WARRANTY; without even the implied warranty of\r
-;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the\r
-;; GNU General Public License for more details.\r
-\r
-;; You should have received a copy of the GNU General Public License\r
-;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.\r
-\r
-;;; Commentary:\r
-\r
-;; Window tree functions.\r
-\r
-;;; Code:\r
-\r
-(eval-when-compile (require 'cl))\r
-\r
-(defvar window-size-fixed nil\r
- "*Non-nil in a buffer means windows displaying the buffer are fixed-size.\r
-If the value is `height', then only the window's height is fixed.\r
-If the value is `width', then only the window's width is fixed.\r
-Any other non-nil value fixes both the width and the height.\r
-Emacs won't change the size of any window displaying that buffer,\r
-unless you explicitly change the size, or Emacs has no other choice.")\r
-(make-variable-buffer-local 'window-size-fixed)\r
-\r
-(defmacro save-selected-window (&rest body)\r
- "Execute BODY, then select the previously selected window.\r
-The value returned is the value of the last form in BODY.\r
-\r
-This macro saves and restores the selected window, as well as the\r
-selected window in each frame. If the previously selected window\r
-is no longer live, then whatever window is selected at the end of\r
-BODY remains selected. If the previously selected window of some\r
-frame is no longer live at the end of BODY, that frame's selected\r
-window is left alone.\r
-\r
-This macro saves and restores the current buffer, since otherwise\r
-its normal operation could make a different buffer current. The\r
-order of recently selected windows and the buffer list ordering\r
-are not altered by this macro (unless they are altered in BODY)."\r
- `(let ((save-selected-window-window (selected-window))\r
- ;; It is necessary to save all of these, because calling\r
- ;; select-window changes frame-selected-window for whatever\r
- ;; frame that window is in.\r
- (save-selected-window-alist\r
- (mapcar (lambda (frame) (cons frame (frame-selected-window frame)))\r
- (frame-list))))\r
- (save-current-buffer\r
- (unwind-protect\r
- (progn ,@body)\r
- (dolist (elt save-selected-window-alist)\r
- (and (frame-live-p (car elt))\r
- (window-live-p (cdr elt))\r
- (set-frame-selected-window (car elt) (cdr elt) 'norecord)))\r
- (when (window-live-p save-selected-window-window)\r
- (select-window save-selected-window-window 'norecord))))))\r
-\r
-(defun window-body-height (&optional window)\r
- "Return number of lines in WINDOW available for actual buffer text.\r
-WINDOW defaults to the selected window.\r
-\r
-The return value does not include the mode line or the header\r
-line, if any. If a line at the bottom of the window is only\r
-partially visible, that line is included in the return value. If\r
-you do not want to include a partially visible bottom line in the\r
-return value, use `window-text-height' instead."\r
- (or window (setq window (selected-window)))\r
- (if (window-minibuffer-p window)\r
- (window-height window)\r
- (with-current-buffer (window-buffer window)\r
- (max 1 (- (window-height window)\r
- (if mode-line-format 1 0)\r
- (if header-line-format 1 0))))))\r
-\r
-(defun one-window-p (&optional nomini all-frames)\r
- "Return non-nil if the selected window is the only window.\r
-Optional arg NOMINI non-nil means don't count the minibuffer\r
-even if it is active. Otherwise, the minibuffer is counted\r
-when it is active.\r
-\r
-The optional arg ALL-FRAMES t means count windows on all frames.\r
-If it is `visible', count windows on all visible frames.\r
-ALL-FRAMES nil or omitted means count only the selected frame,\r
-plus the minibuffer it uses (which may be on another frame).\r
-ALL-FRAMES 0 means count all windows in all visible or iconified frames.\r
-If ALL-FRAMES is anything else, count only the selected frame."\r
- (let ((base-window (selected-window)))\r
- (if (and nomini (eq base-window (minibuffer-window)))\r
- (setq base-window (next-window base-window)))\r
- (eq base-window\r
- (next-window base-window (if nomini 'arg) all-frames))))\r
-\r
-(defun window-current-scroll-bars (&optional window)\r
- "Return the current scroll bar settings for WINDOW.\r
-WINDOW defaults to the selected window.\r
-\r
-The return value is a cons cell (VERTICAL . HORIZONTAL) where\r
-VERTICAL specifies the current location of the vertical scroll\r
-bars (`left', `right', or nil), and HORIZONTAL specifies the\r
-current location of the horizontal scroll bars (`top', `bottom',\r
-or nil).\r
-\r
-Unlike `window-scroll-bars', this function reports the scroll bar\r
-type actually used, once frame defaults and `scroll-bar-mode' are\r
-taken into account."\r
- (let ((vert (nth 2 (window-scroll-bars window)))\r
- (hor nil))\r
- (when (or (eq vert t) (eq hor t))\r
- (let ((fcsb (frame-current-scroll-bars\r
- (window-frame (or window (selected-window))))))\r
- (if (eq vert t)\r
- (setq vert (car fcsb)))\r
- (if (eq hor t)\r
- (setq hor (cdr fcsb)))))\r
- (cons vert hor)))\r
-\r
-(defun walk-windows (proc &optional minibuf all-frames)\r
- "Cycle through all windows, calling PROC for each one.\r
-PROC must specify a function with a window as its sole argument.\r
-The optional arguments MINIBUF and ALL-FRAMES specify the set of\r
-windows to include in the walk, see also `next-window'.\r
-\r
-MINIBUF t means include the minibuffer window even if the\r
-minibuffer is not active. MINIBUF nil or omitted means include\r
-the minibuffer window only if the minibuffer is active. Any\r
-other value means do not include the minibuffer window even if\r
-the minibuffer is active.\r
-\r
-Several frames may share a single minibuffer; if the minibuffer\r
-is active, all windows on all frames that share that minibuffer\r
-are included too. Therefore, if you are using a separate\r
-minibuffer frame and the minibuffer is active and MINIBUF says it\r
-counts, `walk-windows' includes the windows in the frame from\r
-which you entered the minibuffer, as well as the minibuffer\r
-window.\r
-\r
-ALL-FRAMES nil or omitted means cycle through all windows on\r
- WINDOW's frame, plus the minibuffer window if specified by the\r
- MINIBUF argument, see above. If the minibuffer counts, cycle\r
- through all windows on all frames that share that minibuffer\r
- too.\r
-ALL-FRAMES t means cycle through all windows on all existing\r
- frames.\r
-ALL-FRAMES `visible' means cycle through all windows on all\r
- visible frames.\r
-ALL-FRAMES 0 means cycle through all windows on all visible and\r
- iconified frames.\r
-ALL-FRAMES a frame means cycle through all windows on that frame\r
- only.\r
-Anything else means cycle through all windows on WINDOW's frame\r
- and no others.\r
-\r
-This function changes neither the order of recently selected\r
-windows nor the buffer list."\r
- ;; If we start from the minibuffer window, don't fail to come\r
- ;; back to it.\r
- (when (window-minibuffer-p (selected-window))\r
- (setq minibuf t))\r
- ;; Make sure to not mess up the order of recently selected\r
- ;; windows. Use `save-selected-window' and `select-window'\r
- ;; with second argument non-nil for this purpose.\r
- (save-selected-window\r
- (when (framep all-frames)\r
- (select-window (frame-first-window all-frames) 'norecord))\r
- (let* (walk-windows-already-seen\r
- (walk-windows-current (selected-window)))\r
- (while (progn\r
- (setq walk-windows-current\r
- (next-window walk-windows-current minibuf all-frames))\r
- (not (memq walk-windows-current walk-windows-already-seen)))\r
- (setq walk-windows-already-seen\r
- (cons walk-windows-current walk-windows-already-seen))\r
- (funcall proc walk-windows-current)))))\r
-\r
-(defun get-window-with-predicate (predicate &optional minibuf\r
- all-frames default)\r
- "Return a window satisfying PREDICATE.\r
-More precisely, cycle through all windows using `walk-windows',\r
-calling the function PREDICATE on each one of them with the\r
-window as its sole argument. Return the first window for which\r
-PREDICATE returns non-nil. If no window satisfies PREDICATE,\r
-return DEFAULT.\r
-\r
-The optional arguments MINIBUF and ALL-FRAMES specify the set of\r
-windows to include. See `walk-windows' for the meaning of these\r
-arguments."\r
- (catch 'found\r
- (walk-windows #'(lambda (window)\r
- (when (funcall predicate window)\r
- (throw 'found window)))\r
- minibuf all-frames)\r
- default))\r
-\r
-(defalias 'some-window 'get-window-with-predicate)\r
-\r
-;; This should probably be written in C (i.e., without using `walk-windows').\r
-(defun get-buffer-window-list (&optional buffer-or-name minibuf all-frames)\r
- "Return list of all windows displaying BUFFER-OR-NAME, or nil if none.\r
-BUFFER-OR-NAME may be a buffer or the name of an existing buffer\r
-and defaults to the current buffer.\r
-\r
-The optional arguments MINIBUF and ALL-FRAMES specify the set of\r
-windows to consider. See `walk-windows' for the precise meaning\r
-of these arguments."\r
- (let ((buffer (cond\r
- ((not buffer-or-name) (current-buffer))\r
- ((bufferp buffer-or-name) buffer-or-name)\r
- (t (get-buffer buffer-or-name))))\r
- windows)\r
- (walk-windows (function (lambda (window)\r
- (if (eq (window-buffer window) buffer)\r
- (setq windows (cons window windows)))))\r
- minibuf all-frames)\r
- windows))\r
-\r
-(defun minibuffer-window-active-p (window)\r
- "Return t if WINDOW is the currently active minibuffer window."\r
- (eq window (active-minibuffer-window)))\r
-\f\r
-(defun count-windows (&optional minibuf)\r
- "Return the number of visible windows.\r
-The optional argument MINIBUF specifies whether the minibuffer\r
-window shall be counted. See `walk-windows' for the precise\r
-meaning of this argument."\r
- (let ((count 0))\r
- (walk-windows (lambda (w) (setq count (+ count 1)))\r
- minibuf)\r
- count))\r
-\f\r
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;\r
-;;; `balance-windows' subroutines using `window-tree'\r
-\r
-;;; Translate from internal window tree format\r
-\r
-(defun bw-get-tree (&optional window-or-frame)\r
- "Get a window split tree in our format.\r
-\r
-WINDOW-OR-FRAME must be nil, a frame, or a window. If it is nil,\r
-then the whole window split tree for `selected-frame' is returned.\r
-If it is a frame, then this is used instead. If it is a window,\r
-then the smallest tree containing that window is returned."\r
- (when window-or-frame\r
- (unless (or (framep window-or-frame)\r
- (windowp window-or-frame))\r
- (error "Not a frame or window: %s" window-or-frame)))\r
- (let ((subtree (bw-find-tree-sub window-or-frame)))\r
- (when subtree\r
- (if (integerp subtree)\r
- nil\r
- (bw-get-tree-1 subtree)))))\r
-\r
-(defun bw-get-tree-1 (split)\r
- (if (windowp split)\r
- split\r
- (let ((dir (car split))\r
- (edges (car (cdr split)))\r
- (childs (cdr (cdr split))))\r
- (list\r
- (cons 'dir (if dir 'ver 'hor))\r
- (cons 'b (nth 3 edges))\r
- (cons 'r (nth 2 edges))\r
- (cons 't (nth 1 edges))\r
- (cons 'l (nth 0 edges))\r
- (cons 'childs (mapcar #'bw-get-tree-1 childs))))))\r
-\r
-(defun bw-find-tree-sub (window-or-frame &optional get-parent)\r
- (let* ((window (when (windowp window-or-frame) window-or-frame))\r
- (frame (when (windowp window) (window-frame window)))\r
- (wt (car (window-tree frame))))\r
- (when (< 1 (length (window-list frame 0)))\r
- (if window\r
- (bw-find-tree-sub-1 wt window get-parent)\r
- wt))))\r
-\r
-(defun bw-find-tree-sub-1 (tree win &optional get-parent)\r
- (unless (windowp win) (error "Not a window: %s" win))\r
- (if (memq win tree)\r
- (if get-parent\r
- get-parent\r
- tree)\r
- (let ((childs (cdr (cdr tree)))\r
- child\r
- subtree)\r
- (while (and childs (not subtree))\r
- (setq child (car childs))\r
- (setq childs (cdr childs))\r
- (when (and child (listp child))\r
- (setq subtree (bw-find-tree-sub-1 child win get-parent))))\r
- (if (integerp subtree)\r
- (progn\r
- (if (= 1 subtree)\r
- tree\r
- (1- subtree)))\r
- subtree\r
- ))))\r
-\r
-;;; Window or object edges\r
-\r
-(defun bw-l (obj)\r
- "Left edge of OBJ."\r
- (if (windowp obj) (nth 0 (window-edges obj)) (cdr (assq 'l obj))))\r
-(defun bw-t (obj)\r
- "Top edge of OBJ."\r
- (if (windowp obj) (nth 1 (window-edges obj)) (cdr (assq 't obj))))\r
-(defun bw-r (obj)\r
- "Right edge of OBJ."\r
- (if (windowp obj) (nth 2 (window-edges obj)) (cdr (assq 'r obj))))\r
-(defun bw-b (obj)\r
- "Bottom edge of OBJ."\r
- (if (windowp obj) (nth 3 (window-edges obj)) (cdr (assq 'b obj))))\r
-\r
-;;; Split directions\r
-\r
-(defun bw-dir (obj)\r
- "Return window split tree direction if OBJ.\r
-If OBJ is a window return 'both. If it is a window split tree\r
-then return its direction."\r
- (if (symbolp obj)\r
- obj\r
- (if (windowp obj)\r
- 'both\r
- (let ((dir (cdr (assq 'dir obj))))\r
- (unless (memq dir '(hor ver both))\r
- (error "Can't find dir in %s" obj))\r
- dir))))\r
-\r
-(defun bw-eqdir (obj1 obj2)\r
- "Return t if window split tree directions are equal.\r
-OBJ1 and OBJ2 should be either windows or window split trees in\r
-our format. The directions returned by `bw-dir' are compared and\r
-t is returned if they are `eq' or one of them is 'both."\r
- (let ((dir1 (bw-dir obj1))\r
- (dir2 (bw-dir obj2)))\r
- (or (eq dir1 dir2)\r
- (eq dir1 'both)\r
- (eq dir2 'both))))\r
-\r
-;;; Building split tree\r
-\r
-(defun bw-refresh-edges (obj)\r
- "Refresh the edge information of OBJ and return OBJ."\r
- (unless (windowp obj)\r
- (let ((childs (cdr (assq 'childs obj)))\r
- (ol 1000)\r
- (ot 1000)\r
- (or -1)\r
- (ob -1))\r
- (dolist (o childs)\r
- (when (> ol (bw-l o)) (setq ol (bw-l o)))\r
- (when (> ot (bw-t o)) (setq ot (bw-t o)))\r
- (when (< or (bw-r o)) (setq or (bw-r o)))\r
- (when (< ob (bw-b o)) (setq ob (bw-b o))))\r
- (setq obj (delq 'l obj))\r
- (setq obj (delq 't obj))\r
- (setq obj (delq 'r obj))\r
- (setq obj (delq 'b obj))\r
- (add-to-list 'obj (cons 'l ol))\r
- (add-to-list 'obj (cons 't ot))\r
- (add-to-list 'obj (cons 'r or))\r
- (add-to-list 'obj (cons 'b ob))\r
- ))\r
- obj)\r
-\r
-;;; Balance windows\r
-\r
-(defun balance-windows (&optional window-or-frame)\r
- "Make windows the same heights or widths in window split subtrees.\r
-\r
-When called non-interactively WINDOW-OR-FRAME may be either a\r
-window or a frame. It then balances the windows on the implied\r
-frame. If the parameter is a window only the corresponding window\r
-subtree is balanced."\r
- (interactive)\r
- (let (\r
- (wt (bw-get-tree window-or-frame))\r
- (w)\r
- (h)\r
- (tried-sizes)\r
- (last-sizes)\r
- (windows (window-list nil 0)))\r
- (when wt\r
- (while (not (member last-sizes tried-sizes))\r
- (when last-sizes (setq tried-sizes (cons last-sizes tried-sizes)))\r
- (setq last-sizes (mapcar (lambda (w)\r
- (window-edges w))\r
- windows))\r
- (when (eq 'hor (bw-dir wt))\r
- (setq w (- (bw-r wt) (bw-l wt))))\r
- (when (eq 'ver (bw-dir wt))\r
- (setq h (- (bw-b wt) (bw-t wt))))\r
- (bw-balance-sub wt w h)))))\r
-\r
-(defun bw-adjust-window (window delta horizontal)\r
- "Wrapper around `adjust-window-trailing-edge' with error checking.\r
-Arguments WINDOW, DELTA and HORIZONTAL are passed on to that function."\r
- ;; `adjust-window-trailing-edge' may fail if delta is too large.\r
- (while (>= (abs delta) 1)\r
- (condition-case err\r
- (progn\r
- (adjust-window-trailing-edge window delta horizontal)\r
- (setq delta 0))\r
- (error\r
- ;;(message "adjust: %s" (error-message-string err))\r
- (setq delta (/ delta 2))))))\r
-\r
-(defun bw-balance-sub (wt w h)\r
- (setq wt (bw-refresh-edges wt))\r
- (unless w (setq w (- (bw-r wt) (bw-l wt))))\r
- (unless h (setq h (- (bw-b wt) (bw-t wt))))\r
- (if (windowp wt)\r
- (progn\r
- (when w\r
- (let ((dw (- w (- (bw-r wt) (bw-l wt)))))\r
- (when (/= 0 dw)\r
- (bw-adjust-window wt dw t))))\r
- (when h\r
- (let ((dh (- h (- (bw-b wt) (bw-t wt)))))\r
- (when (/= 0 dh)\r
- (bw-adjust-window wt dh nil)))))\r
- (let* ((childs (cdr (assq 'childs wt)))\r
- (cw (when w (/ w (if (bw-eqdir 'hor wt) (length childs) 1))))\r
- (ch (when h (/ h (if (bw-eqdir 'ver wt) (length childs) 1)))))\r
- (dolist (c childs)\r
- (bw-balance-sub c cw ch)))))\r
-\r
-(defun window-fixed-size-p (&optional window direction)\r
- "Return t if WINDOW cannot be resized in DIRECTION.\r
-WINDOW defaults to the selected window. DIRECTION can be\r
-nil (i.e. any), `height' or `width'."\r
- (with-current-buffer (window-buffer window)\r
- (when (and (boundp 'window-size-fixed) window-size-fixed)\r
- (not (and direction\r
- (member (cons direction window-size-fixed)\r
- '((height . width) (width . height))))))))\r
-\r
-;;; A different solution to balance-windows.\r
-\r
-(defvar window-area-factor 1\r
- "Factor by which the window area should be over-estimated.\r
-This is used by `balance-windows-area'.\r
-Changing this globally has no effect.")\r
-(make-variable-buffer-local 'window-area-factor)\r
-\r
-(defun balance-windows-area ()\r
- "Make all visible windows the same area (approximately).\r
-See also `window-area-factor' to change the relative size of\r
-specific buffers."\r
- (interactive)\r
- (let* ((unchanged 0) (carry 0) (round 0)\r
- ;; Remove fixed-size windows.\r
- (wins (delq nil (mapcar (lambda (win)\r
- (if (not (window-fixed-size-p win)) win))\r
- (window-list nil 'nomini))))\r
- (changelog nil)\r
- next)\r
- ;; Resizing a window changes the size of surrounding windows in complex\r
- ;; ways, so it's difficult to balance them all. The introduction of\r
- ;; `adjust-window-trailing-edge' made it a bit easier, but it is still\r
- ;; very difficult to do. `balance-window' above takes an off-line\r
- ;; approach: get the whole window tree, then balance it, then try to\r
- ;; adjust the windows so they fit the result.\r
- ;; Here, instead, we take a "local optimization" approach, where we just\r
- ;; go through all the windows several times until nothing needs to be\r
- ;; changed. The main problem with this approach is that it's difficult\r
- ;; to make sure it terminates, so we use some heuristic to try and break\r
- ;; off infinite loops.\r
- ;; After a round without any change, we allow a second, to give a chance\r
- ;; to the carry to propagate a minor imbalance from the end back to\r
- ;; the beginning.\r
- (while (< unchanged 2)\r
- ;; (message "New round")\r
- (setq unchanged (1+ unchanged) round (1+ round))\r
- (dolist (win wins)\r
- (setq next win)\r
- (while (progn (setq next (next-window next))\r
- (window-fixed-size-p next)))\r
- ;; (assert (eq next (or (cadr (member win wins)) (car wins))))\r
- (let* ((horiz\r
- (< (car (window-edges win)) (car (window-edges next))))\r
- (areadiff (/ (- (* (window-height next) (window-width next)\r
- (buffer-local-value 'window-area-factor\r
- (window-buffer next)))\r
- (* (window-height win) (window-width win)\r
- (buffer-local-value 'window-area-factor\r
- (window-buffer win))))\r
- (max (buffer-local-value 'window-area-factor\r
- (window-buffer win))\r
- (buffer-local-value 'window-area-factor\r
- (window-buffer next)))))\r
- (edgesize (if horiz\r
- (+ (window-height win) (window-height next))\r
- (+ (window-width win) (window-width next))))\r
- (diff (/ areadiff edgesize)))\r
- (when (zerop diff)\r
- ;; Maybe diff is actually closer to 1 than to 0.\r
- (setq diff (/ (* 3 areadiff) (* 2 edgesize))))\r
- (when (and (zerop diff) (not (zerop areadiff)))\r
- (setq diff (/ (+ areadiff carry) edgesize))\r
- ;; Change things smoothly.\r
- (if (or (> diff 1) (< diff -1)) (setq diff (/ diff 2))))\r
- (if (zerop diff)\r
- ;; Make sure negligible differences don't accumulate to\r
- ;; become significant.\r
- (setq carry (+ carry areadiff))\r
- (bw-adjust-window win diff horiz)\r
- ;; (sit-for 0.5)\r
- (let ((change (cons win (window-edges win))))\r
- ;; If the same change has been seen already for this window,\r
- ;; we're most likely in an endless loop, so don't count it as\r
- ;; a change.\r
- (unless (member change changelog)\r
- (push change changelog)\r
- (setq unchanged 0 carry 0)))))))\r
- ;; We've now basically balanced all the windows.\r
- ;; But there may be some minor off-by-one imbalance left over,\r
- ;; so let's do some fine tuning.\r
- ;; (bw-finetune wins)\r
- ;; (message "Done in %d rounds" round)\r
- ))\r
-\r
-\f\r
-(defcustom display-buffer-function nil\r
- "If non-nil, function to call to handle `display-buffer'.\r
-It will receive two args, the buffer and a flag which if non-nil\r
-means that the currently selected window is not acceptable. It\r
-should choose or create a window, display the specified buffer in\r
-it, and return the window.\r
-\r
-Commands such as `switch-to-buffer-other-window' and\r
-`find-file-other-window' work using this function."\r
- :type '(choice\r
- (const nil)\r
- (function :tag "function"))\r
- :group 'windows)\r
-\r
-(defun special-display-p (buffer-name)\r
- "Return non-nil if a buffer named BUFFER-NAME gets a special frame.\r
-If the value is t, `display-buffer' or `pop-to-buffer' would\r
-create a special frame for that buffer using the default frame\r
-parameters.\r
-\r
-If the value is a list, it is a list of frame parameters that\r
-would be used to make a frame for that buffer. The variables\r
-`special-display-buffer-names' and `special-display-regexps'\r
-control this."\r
- (let (tmp)\r
- (cond\r
- ((not (stringp buffer-name)))\r
- ;; Make sure to return t in the following two cases.\r
- ((member buffer-name special-display-buffer-names) t)\r
- ((setq tmp (assoc buffer-name special-display-buffer-names)) (cdr tmp))\r
- ((catch 'found\r
- (dolist (regexp special-display-regexps)\r
- (cond\r
- ((stringp regexp)\r
- (when (string-match-p regexp buffer-name)\r
- (throw 'found t)))\r
- ((and (consp regexp) (stringp (car regexp))\r
- (string-match-p (car regexp) buffer-name))\r
- (throw 'found (cdr regexp))))))))))\r
-\r
-(defcustom special-display-buffer-names nil\r
- "List of buffer names that should have their own special frames.\r
-Displaying a buffer with `display-buffer' or `pop-to-buffer', if\r
-its name is in this list, makes a special frame for it using\r
-`special-display-function'. See also `special-display-regexps'.\r
-\r
-An element of the list can be a list instead of just a string.\r
-There are two ways to use a list as an element:\r
- (BUFFER FRAME-PARAMETERS...) (BUFFER FUNCTION OTHER-ARGS...)\r
-In the first case, the FRAME-PARAMETERS are pairs of the form\r
-\(PARAMETER . VALUE); these parameter values are used to create\r
-the frame. In the second case, FUNCTION is called with BUFFER as\r
-the first argument, followed by the OTHER-ARGS--it can display\r
-BUFFER in any way it likes. All this is done by the function\r
-found in `special-display-function'.\r
-\r
-If the specified frame parameters include (same-buffer . t), the\r
-buffer is displayed in the currently selected window. Otherwise, if\r
-they include (same-frame . t), the buffer is displayed in a new window\r
-in the currently selected frame.\r
-\r
-If this variable appears \"not to work\", because you add a name to it\r
-but that buffer still appears in the selected window, look at the\r
-values of `same-window-buffer-names' and `same-window-regexps'.\r
-Those variables take precedence over this one."\r
- :type '(repeat (choice :tag "Buffer"\r
- :value ""\r
- (string :format "%v")\r
- (cons :tag "With attributes"\r
- :format "%v"\r
- :value ("" . nil)\r
- (string :format "%v")\r
- (repeat :tag "Attributes"\r
- (cons :format "%v"\r
- (symbol :tag "Parameter")\r
- (sexp :tag "Value"))))))\r
- :group 'frames)\r
-\r
-(defcustom special-display-regexps nil\r
- "List of regexps saying which buffers should have their own special frames.\r
-When displaying a buffer with `display-buffer' or\r
-`pop-to-buffer', if any regexp in this list matches the buffer\r
-name, it makes a special frame for the buffer by calling\r
-`special-display-function'.\r
-\r
-An element of the list can be a list instead of just a string.\r
-There are two ways to use a list as an element:\r
- (REGEXP FRAME-PARAMETERS...) (REGEXP FUNCTION OTHER-ARGS...)\r
-In the first case, the FRAME-PARAMETERS are pairs of the form\r
-\(PARAMETER . VALUE); these parameter values are used to create\r
-the frame. In the second case, FUNCTION is called with BUFFER as\r
-the first argument, followed by the OTHER-ARGS--it can display\r
-the buffer in any way it likes. All this is done by the function\r
-found in `special-display-function'.\r
-\r
-If the specified frame parameters include (same-buffer . t), the\r
-buffer is displayed in the currently selected window. Otherwise,\r
-if they include (same-frame . t), the buffer is displayed in a\r
-new window in the currently selected frame.\r
-\r
-If this variable appears \"not to work\", because you add a\r
-regexp to it but the matching buffers still appear in the\r
-selected window, look at the values of `same-window-buffer-names'\r
-and `same-window-regexps'. Those variables take precedence over\r
-this one."\r
- :type '(repeat (choice :tag "Buffer"\r
- :value ""\r
- (regexp :format "%v")\r
- (cons :tag "With attributes"\r
- :format "%v"\r
- :value ("" . nil)\r
- (regexp :format "%v")\r
- (repeat :tag "Attributes"\r
- (cons :format "%v"\r
- (symbol :tag "Parameter")\r
- (sexp :tag "Value"))))))\r
- :group 'frames)\r
-\r
-(defcustom special-display-function 'special-display-popup-frame\r
- "Function to call to make a new frame for a special buffer.\r
-It is called with two arguments, the buffer and optional buffer\r
-specific data, and should return a window displaying that buffer.\r
-The default value normally makes a separate frame for the buffer,\r
-using `special-display-frame-alist' to specify the frame\r
-parameters.\r
-\r
-But if the buffer specific data includes (same-buffer . t) then\r
-the buffer is displayed in the current selected window.\r
-Otherwise if it includes (same-frame . t) then the buffer is\r
-displayed in a new window in the currently selected frame.\r
-\r
-A buffer is special if it is listed in\r
-`special-display-buffer-names' or matches a regexp in\r
-`special-display-regexps'."\r
- :type 'function\r
- :group 'frames)\r
-\r
-(defun same-window-p (buffer-name)\r
- "Return non-nil if a buffer named BUFFER-NAME would be shown in the \"same\" window.\r
-This function returns non-nil if `display-buffer' or\r
-`pop-to-buffer' would show a buffer named BUFFER-NAME in the\r
-selected rather than \(as usual\) some other window. See\r
-`same-window-buffer-names' and `same-window-regexps'."\r
- (cond\r
- ((not (stringp buffer-name)))\r
- ;; The elements of `same-window-buffer-names' can be buffer\r
- ;; names or cons cells whose cars are buffer names.\r
- ((member buffer-name same-window-buffer-names))\r
- ((assoc buffer-name same-window-buffer-names))\r
- ((catch 'found\r
- (dolist (regexp same-window-regexps)\r
- ;; The elements of `same-window-regexps' can be regexps\r
- ;; or cons cells whose cars are regexps.\r
- (when (or (and (stringp regexp)\r
- (string-match regexp buffer-name))\r
- (and (consp regexp) (stringp (car regexp))\r
- (string-match-p (car regexp) buffer-name)))\r
- (throw 'found t)))))))\r
-\r
-(defcustom same-window-buffer-names nil\r
- "List of names of buffers that should appear in the \"same\" window.\r
-`display-buffer' and `pop-to-buffer' show a buffer whose name is\r
-on this list in the selected rather than some other window.\r
-\r
-An element of this list can be a cons cell instead of just a\r
-string. In that case the car must be a string specifying the\r
-buffer name. This is for compatibility with\r
-`special-display-buffer-names'; the cdr of the cons cell is\r
-ignored.\r
-\r
-See also `same-window-regexps'."\r
- :type '(repeat (string :format "%v"))\r
- :group 'windows)\r
-\r
-(defcustom same-window-regexps nil\r
- "List of regexps saying which buffers should appear in the \"same\" window.\r
-`display-buffer' and `pop-to-buffer' show a buffer whose name\r
-matches a regexp on this list in the selected rather than some\r
-other window.\r
-\r
-An element of this list can be a cons cell instead of just a\r
-string. In that case the car must be a string, which specifies\r
-the buffer name. This is for compatibility with\r
-`special-display-buffer-names'; the cdr of the cons cell is\r
-ignored.\r
-\r
-See also `same-window-buffer-names'."\r
- :type '(repeat (regexp :format "%v"))\r
- :group 'windows)\r
-\r
-(defcustom pop-up-frames nil\r
- "Whether `display-buffer' should make a separate frame.\r
-If nil, never make a seperate frame.\r
-If the value is `graphic-only', make a separate frame\r
-on graphic displays only.\r
-Any other non-nil value means always make a separate frame."\r
- :type '(choice\r
- (const :tag "Never" nil)\r
- (const :tag "On graphic displays only" graphic-only)\r
- (const :tag "Always" t))\r
- :group 'windows)\r
-\r
-(defcustom display-buffer-reuse-frames nil\r
- "Non-nil means `display-buffer' should reuse frames.\r
-If the buffer in question is already displayed in a frame, raise\r
-that frame."\r
- :type 'boolean\r
- :version "21.1"\r
- :group 'windows)\r
-\r
-(defcustom pop-up-windows t\r
- "Non-nil means `display-buffer' should make a new window."\r
- :type 'boolean\r
- :group 'windows)\r
-\r
-(defcustom split-height-threshold 80\r
- "Minimum height of window to be split vertically.\r
-If the value is a number, `display-buffer' can split a window\r
-only if it has at least as many lines. If the value is nil,\r
-`display-buffer' cannot split a window vertically.\r
-\r
-If the window is the only window on its frame, `display-buffer'\r
-can split it regardless of this value."\r
- :type '(choice (const nil) (number :tag "lines"))\r
- :version "23.1"\r
- :group 'windows)\r
-\r
-(defcustom split-width-threshold 160\r
- "Minimum width of window to be split horizontally.\r
-If the value is a number, `display-buffer' can split a window\r
-only if it has at least as many columns. If the value is nil,\r
-`display-buffer' cannot split a window horizontally."\r
- :type '(choice (const nil) (number :tag "columns"))\r
- :version "23.1"\r
- :group 'windows)\r
-\r
-(defcustom split-window-preferred-function nil\r
- "Function used by `display-buffer' to split windows.\r
-If non-nil, a function called with a window as single argument\r
-supposed to split that window and return the new window. If the\r
-function returns nil the window is not split.\r
-\r
-If nil, `display-buffer' will split the window respecting the\r
-values of `split-height-threshold' and `split-width-threshold'."\r
- :type '(choice (const nil) (function :tag "Function"))\r
- :version "23.1"\r
- :group 'windows)\r
-\r
-(defun window--splittable-p (window &optional horizontal)\r
- "Return non-nil if WINDOW can be split evenly.\r
-Optional argument HORIZONTAL non-nil means check whether WINDOW\r
-can be split horizontally.\r
-\r
-WINDOW can be split vertically when the following conditions\r
-hold:\r
-\r
-- `window-size-fixed' is either nil or equals `width' for the\r
- buffer of WINDOW.\r
-\r
-- `split-height-threshold' is a number and WINDOW is at least as\r
- high as `split-height-threshold'.\r
-\r
-- When WINDOW is split evenly, the emanating windows are at least\r
- `window-min-height' lines tall and can accommodate at least one\r
- line plus - if WINDOW has one - a mode line.\r
-\r
-WINDOW can be split horizontally when the following conditions\r
-hold:\r
-\r
-- `window-size-fixed' is either nil or equals `height' for the\r
- buffer of WINDOW.\r
-\r
-- `split-width-threshold' is a number and WINDOW is at least as\r
- wide as `split-width-threshold'.\r
-\r
-- When WINDOW is split evenly, the emanating windows are at least\r
- `window-min-width' or two (whichever is larger) columns wide."\r
- (when (window-live-p window)\r
- (with-current-buffer (window-buffer window)\r
- (if horizontal\r
- ;; A window can be split horizontally when its width is not\r
- ;; fixed, it is at least `split-width-threshold' columns wide\r
- ;; and at least twice as wide as `window-min-width' and 2 (the\r
- ;; latter value is hardcoded).\r
- (and (memq window-size-fixed '(nil height))\r
- ;; Testing `window-full-width-p' here hardly makes any\r
- ;; sense nowadays. This can be done more intuitively by\r
- ;; setting up `split-width-threshold' appropriately.\r
- (numberp split-width-threshold)\r
- (>= (window-width window)\r
- (max split-width-threshold\r
- (* 2 (max window-min-width 2)))))\r
- ;; A window can be split vertically when its height is not\r
- ;; fixed, it is at least `split-height-threshold' lines high,\r
- ;; and it is at least twice as high as `window-min-height' and 2\r
- ;; if it has a modeline or 1.\r
- (and (memq window-size-fixed '(nil width))\r
- (numberp split-height-threshold)\r
- (>= (window-height window)\r
- (max split-height-threshold\r
- (* 2 (max window-min-height\r
- (if mode-line-format 2 1))))))))))\r
-\r
-(defun window--try-to-split-window (window)\r
- "Split WINDOW if it is splittable.\r
-See `window--splittable-p' for how to determine whether a window\r
-is splittable. If WINDOW can be split, return the value returned\r
-by `split-window' (or `split-window-preferred-function')."\r
- (when (and (window-live-p window)\r
- (not (frame-parameter (window-frame window) 'unsplittable)))\r
- (if (functionp split-window-preferred-function)\r
- ;; `split-window-preferred-function' is specified, so use it.\r
- (funcall split-window-preferred-function window)\r
- (or (and (window--splittable-p window)\r
- ;; Split window vertically.\r
- (split-window window))\r
- (and (window--splittable-p window t)\r
- ;; Split window horizontally.\r
- (split-window window nil t))\r
- (and (eq window (frame-root-window (window-frame window)))\r
- (not (window-minibuffer-p window))\r
- ;; If WINDOW is the only window on its frame and not the\r
- ;; minibuffer window, attempt to split it vertically\r
- ;; disregarding the value of `split-height-threshold'.\r
- (let ((split-height-threshold 0))\r
- (and (window--splittable-p window)\r
- (split-window window))))))))\r
-\r
-(defun window--frame-usable-p (frame)\r
- "Return FRAME if it can be used to display a buffer."\r
- (when (frame-live-p frame)\r
- (let ((window (frame-root-window frame)))\r
- ;; `frame-root-window' may be an internal window which is considered\r
- ;; "dead" by `window-live-p'. Hence if `window' is not live we\r
- ;; implicitly know that `frame' has a visible window we can use.\r
- (when (or (not (window-live-p window))\r
- (and (not (window-minibuffer-p window))\r
- (not (window-dedicated-p window))))\r
- frame))))\r
-\r
-(defcustom even-window-heights t\r
- "If non-nil `display-buffer' will try to even window heights.\r
-Otherwise `display-buffer' will leave the window configuration\r
-alone. Heights are evened only when `display-buffer' chooses a\r
-window that appears above or below the selected window."\r
- :type 'boolean\r
- :group 'windows)\r
-\r
-(defun window--even-window-heights (window)\r
- "Even heights of WINDOW and selected window.\r
-Do this only if these windows are vertically adjacent to each\r
-other, `even-window-heights' is non-nil, and the selected window\r
-is higher than WINDOW."\r
- (when (and even-window-heights\r
- (not (eq window (selected-window)))\r
- ;; Don't resize minibuffer windows.\r
- (not (window-minibuffer-p (selected-window)))\r
- (> (window-height (selected-window)) (window-height window)) \r
- (eq (window-frame window) (window-frame (selected-window)))\r
- (let ((sel-edges (window-edges (selected-window)))\r
- (win-edges (window-edges window)))\r
- (and (= (nth 0 sel-edges) (nth 0 win-edges))\r
- (= (nth 2 sel-edges) (nth 2 win-edges))\r
- (or (= (nth 1 sel-edges) (nth 3 win-edges))\r
- (= (nth 3 sel-edges) (nth 1 win-edges))))))\r
- (let ((window-min-height 1))\r
- ;; Don't throw an error if we can't even window heights for\r
- ;; whatever reason.\r
- (condition-case nil\r
- (enlarge-window (/ (- (window-height window) (window-height)) 2))\r
- (error nil)))))\r
-\r
-(defun window--display-buffer-1 (window)\r
- "Raise the frame containing WINDOW.\r
-Do not raise the selected frame. Return WINDOW."\r
- (let* ((frame (window-frame window))\r
- (visible (frame-visible-p frame)))\r
- (unless (or (not visible)\r
- ;; Assume the selected frame is already visible enough.\r
- (eq frame (selected-frame))\r
- ;; Assume the frame from which we invoked the minibuffer\r
- ;; is visible.\r
- (and (minibuffer-window-active-p (selected-window))\r
- (eq frame (window-frame (minibuffer-selected-window)))))\r
- (raise-frame frame))\r
- window))\r
-\r
-(defun window--display-buffer-2 (buffer window)\r
- "Display BUFFER in WINDOW and make its frame visible.\r
-Return WINDOW."\r
- (when (and (buffer-live-p buffer) (window-live-p window))\r
- (set-window-buffer window buffer)\r
- (window--display-buffer-1 window)))\r
-\r
-(defun display-buffer (buffer-or-name &optional not-this-window frame)\r
- "Make buffer BUFFER-OR-NAME appear in some window but don't select it.\r
-BUFFER-OR-NAME must be a buffer or the name of an existing\r
-buffer. Return the window chosen to display BUFFER-OR-NAME or\r
-nil if no such window is found.\r
-\r
-Optional argument NOT-THIS-WINDOW non-nil means display the\r
-buffer in a window other than the selected one, even if it is\r
-already displayed in the selected window.\r
-\r
-Optional argument FRAME specifies which frames to investigate\r
-when the specified buffer is already displayed. If the buffer is\r
-already displayed in some window on one of these frames simply\r
-return that window. Possible values of FRAME are:\r
-\r
-`visible' - consider windows on all visible frames.\r
-\r
-0 - consider windows on all visible or iconified frames.\r
-\r
-t - consider windows on all frames.\r
-\r
-A specific frame - consider windows on that frame only.\r
-\r
-nil - consider windows on the selected frame \(actually the\r
-last non-minibuffer frame\) only. If, however, either\r
-`display-buffer-reuse-frames' or `pop-up-frames' is non-nil\r
-\(non-nil and not graphic-only on a text-only terminal),\r
-consider all visible or iconified frames."\r
- (interactive "BDisplay buffer:\nP")\r
- (let* ((can-use-selected-window\r
- ;; The selected window is usable unless either NOT-THIS-WINDOW\r
- ;; is non-nil, it is dedicated to its buffer, or it is the\r
- ;; `minibuffer-window'.\r
- (not (or not-this-window\r
- (window-dedicated-p (selected-window))\r
- (window-minibuffer-p))))\r
- (buffer (if (bufferp buffer-or-name)\r
- buffer-or-name\r
- (get-buffer buffer-or-name)))\r
- (name-of-buffer (buffer-name buffer))\r
- ;; On text-only terminals do not pop up a new frame when\r
- ;; `pop-up-frames' equals graphic-only.\r
- (use-pop-up-frames (if (eq pop-up-frames 'graphic-only)\r
- (display-graphic-p)\r
- pop-up-frames))\r
- ;; `frame-to-use' is the frame where to show `buffer' - either\r
- ;; the selected frame or the last nonminibuffer frame.\r
- (frame-to-use\r
- (or (window--frame-usable-p (selected-frame))\r
- (window--frame-usable-p (last-nonminibuffer-frame))))\r
- ;; `window-to-use' is the window we use for showing `buffer'.\r
- window-to-use)\r
- (cond\r
- ((not (buffer-live-p buffer))\r
- (error "No such buffer %s" buffer))\r
- (display-buffer-function\r
- ;; Let `display-buffer-function' do the job.\r
- (funcall display-buffer-function buffer not-this-window))\r
- ((and (not not-this-window)\r
- (eq (window-buffer (selected-window)) buffer))\r
- ;; The selected window already displays BUFFER and\r
- ;; `not-this-window' is nil, so use it.\r
- (window--display-buffer-1 (selected-window)))\r
- ((and can-use-selected-window (same-window-p name-of-buffer))\r
- ;; If the buffer's name tells us to use the selected window do so.\r
- (window--display-buffer-2 buffer (selected-window)))\r
- ((let ((frames (or frame\r
- (and (or use-pop-up-frames\r
- display-buffer-reuse-frames\r
- (not (last-nonminibuffer-frame)))\r
- 0)\r
- (last-nonminibuffer-frame))))\r
- (and (setq window-to-use (get-buffer-window buffer frames))\r
- (or can-use-selected-window\r
- (not (eq (selected-window) window-to-use)))))\r
- ;; If the buffer is already displayed in some window use that.\r
- (window--display-buffer-1 window-to-use))\r
- ((and special-display-function\r
- ;; `special-display-p' returns either t or a list of frame\r
- ;; parameters to pass to `special-display-function'.\r
- (let ((pars (special-display-p name-of-buffer)))\r
- (when pars\r
- (funcall special-display-function\r
- buffer (if (listp pars) pars))))))\r
- ((or use-pop-up-frames (not frame-to-use))\r
- ;; We want or need a new frame.\r
- (window--display-buffer-2\r
- buffer (frame-selected-window (funcall pop-up-frame-function))))\r
- ((and pop-up-windows\r
- ;; Make a new window.\r
- (or (not (frame-parameter frame-to-use 'unsplittable))\r
- ;; If the selected frame cannot be split look at\r
- ;; `last-nonminibuffer-frame'.\r
- (and (eq frame-to-use (selected-frame))\r
- (setq frame-to-use (last-nonminibuffer-frame))\r
- (window--frame-usable-p frame-to-use)\r
- (not (frame-parameter frame-to-use 'unsplittable))))\r
- ;; Attempt to split largest or least recently used window.\r
- (setq window-to-use\r
- (or (window--try-to-split-window\r
- (get-largest-window frame-to-use t))\r
- (window--try-to-split-window\r
- (get-lru-window frame-to-use t))))\r
- (window--display-buffer-2 buffer window-to-use)))\r
- ((setq window-to-use\r
- ;; Reuse an existing window.\r
- (or (get-lru-window frame-to-use)\r
- (get-buffer-window buffer 'visible)\r
- (get-largest-window 'visible nil)\r
- (get-buffer-window buffer 0)\r
- (get-largest-window 0 nil)\r
- (frame-selected-window (funcall pop-up-frame-function))))\r
- (window--even-window-heights window-to-use)\r
- (window--display-buffer-2 buffer window-to-use)))))\r
-\r
-(defun pop-to-buffer (buffer-or-name &optional other-window norecord)\r
- "Select buffer BUFFER-OR-NAME in some window, preferably a different one.\r
-BUFFER-OR-NAME may be a buffer, a string \(a buffer name), or\r
-nil. If BUFFER-OR-NAME is a string not naming an existent\r
-buffer, create a buffer with that name. If BUFFER-OR-NAME is\r
-nil, choose some other buffer.\r
-\r
-If `pop-up-windows' is non-nil, windows can be split to display\r
-the buffer. If optional second arg OTHER-WINDOW is non-nil,\r
-insist on finding another window even if the specified buffer is\r
-already visible in the selected window, and ignore\r
-`same-window-regexps' and `same-window-buffer-names'.\r
-\r
-If the window to show BUFFER-OR-NAME is not on the selected\r
-frame, raise that window's frame and give it input focus.\r
-\r
-This function returns the buffer it switched to. This uses the\r
-function `display-buffer' as a subroutine; see the documentation\r
-of `display-buffer' for additional customization information.\r
-\r
-Optional third arg NORECORD non-nil means do not put this buffer\r
-at the front of the list of recently selected ones."\r
- (let ((buffer\r
- ;; FIXME: This behavior is carried over from the previous C version\r
- ;; of pop-to-buffer, but really we should use just\r
- ;; `get-buffer' here.\r
- (if (null buffer-or-name) (other-buffer (current-buffer))\r
- (or (get-buffer buffer-or-name)\r
- (let ((buf (get-buffer-create buffer-or-name)))\r
- (set-buffer-major-mode buf)\r
- buf))))\r
- (old-window (selected-window))\r
- (old-frame (selected-frame))\r
- new-window new-frame)\r
- (set-buffer buffer)\r
- (setq new-window (display-buffer buffer other-window))\r
- (unless (eq new-window old-window)\r
- ;; `display-buffer' has chosen another window, select it.\r
- (select-window new-window norecord)\r
- (setq new-frame (window-frame new-window))\r
- (unless (eq new-frame old-frame)\r
- ;; `display-buffer' has chosen another frame, make sure it gets\r
- ;; input focus and is risen.\r
- (select-frame-set-input-focus new-frame)))\r
- buffer))\r
-\r
-;; I think this should be the default; I think people will prefer it--rms.\r
-(defcustom split-window-keep-point t\r
- "If non-nil, \\[split-window-vertically] keeps the original point \\r
-in both children.\r
-This is often more convenient for editing.\r
-If nil, adjust point in each of the two windows to minimize redisplay.\r
-This is convenient on slow terminals, but point can move strangely.\r
-\r
-This option applies only to `split-window-vertically' and\r
-functions that call it. `split-window' always keeps the original\r
-point in both children."\r
- :type 'boolean\r
- :group 'windows)\r
-\r
-(defun split-window-vertically (&optional size)\r
- "Split selected window into two windows, one above the other.\r
-The upper window gets SIZE lines and the lower one gets the rest.\r
-SIZE negative means the lower window gets -SIZE lines and the\r
-upper one the rest. With no argument, split windows equally or\r
-close to it. Both windows display the same buffer, now current.\r
-\r
-If the variable `split-window-keep-point' is non-nil, both new\r
-windows will get the same value of point as the selected window.\r
-This is often more convenient for editing. The upper window is\r
-the selected window.\r
-\r
-Otherwise, we choose window starts so as to minimize the amount of\r
-redisplay; this is convenient on slow terminals. The new selected\r
-window is the one that the current value of point appears in. The\r
-value of point can change if the text around point is hidden by the\r
-new mode line.\r
-\r
-Regardless of the value of `split-window-keep-point', the upper\r
-window is the original one and the return value is the new, lower\r
-window."\r
- (interactive "P")\r
- (let ((old-window (selected-window))\r
- (old-point (point))\r
- (size (and size (prefix-numeric-value size)))\r
- moved-by-window-height moved new-window bottom)\r
- (and size (< size 0)\r
- ;; Handle negative SIZE value.\r
- (setq size (+ (window-height) size)))\r
- (setq new-window (split-window nil size))\r
- (unless split-window-keep-point\r
- (save-excursion\r
- (set-buffer (window-buffer))\r
- (goto-char (window-start))\r
- (setq moved (vertical-motion (window-height)))\r
- (set-window-start new-window (point))\r
- (when (> (point) (window-point new-window))\r
- (set-window-point new-window (point)))\r
- (when (= moved (window-height))\r
- (setq moved-by-window-height t)\r
- (vertical-motion -1))\r
- (setq bottom (point)))\r
- (and moved-by-window-height\r
- (<= bottom (point))\r
- (set-window-point old-window (1- bottom)))\r
- (and moved-by-window-height\r
- (<= (window-start new-window) old-point)\r
- (set-window-point new-window old-point)\r
- (select-window new-window)))\r
- (split-window-save-restore-data new-window old-window)))\r
-\r
-;; This is to avoid compiler warnings.\r
-(defvar view-return-to-alist)\r
-\r
-(defun split-window-save-restore-data (new-window old-window)\r
- (with-current-buffer (window-buffer)\r
- (when view-mode\r
- (let ((old-info (assq old-window view-return-to-alist)))\r
- (when old-info\r
- (push (cons new-window (cons (car (cdr old-info)) t))\r
- view-return-to-alist))))\r
- new-window))\r
-\r
-(defun split-window-horizontally (&optional size)\r
- "Split selected window into two windows side by side.\r
-The selected window becomes the left one and gets SIZE columns.\r
-SIZE negative means the right window gets -SIZE lines.\r
-\r
-SIZE includes the width of the window's scroll bar; if there are\r
-no scroll bars, it includes the width of the divider column to\r
-the window's right, if any. SIZE omitted or nil means split\r
-window equally.\r
-\r
-The selected window remains selected. Return the new window."\r
- (interactive "P")\r
- (let ((old-window (selected-window))\r
- (size (and size (prefix-numeric-value size))))\r
- (and size (< size 0)\r
- ;; Handle negative SIZE value.\r
- (setq size (+ (window-width) size)))\r
- (split-window-save-restore-data (split-window nil size t) old-window)))\r
-\r
-\f\r
-(defun set-window-text-height (window height)\r
- "Sets the height in lines of the text display area of WINDOW to HEIGHT.\r
-HEIGHT doesn't include the mode line or header line, if any, or\r
-any partial-height lines in the text display area.\r
-\r
-Note that the current implementation of this function cannot\r
-always set the height exactly, but attempts to be conservative,\r
-by allocating more lines than are actually needed in the case\r
-where some error may be present."\r
- (let ((delta (- height (window-text-height window))))\r
- (unless (zerop delta)\r
- ;; Setting window-min-height to a value like 1 can lead to very\r
- ;; bizarre displays because it also allows Emacs to make *other*\r
- ;; windows 1-line tall, which means that there's no more space for\r
- ;; the modeline.\r
- (let ((window-min-height (min 2 height))) ; One text line plus a modeline.\r
- (if (and window (not (eq window (selected-window))))\r
- (save-selected-window\r
- (select-window window 'norecord)\r
- (enlarge-window delta))\r
- (enlarge-window delta))))))\r
-\r
-\f\r
-(defun enlarge-window-horizontally (columns)\r
- "Make selected window COLUMNS wider.\r
-Interactively, if no argument is given, make selected window one\r
-column wider."\r
- (interactive "p")\r
- (enlarge-window columns t))\r
-\r
-(defun shrink-window-horizontally (columns)\r
- "Make selected window COLUMNS narrower.\r
-Interactively, if no argument is given, make selected window one\r
-column narrower."\r
- (interactive "p")\r
- (shrink-window columns t))\r
-\r
-(defun window-buffer-height (window)\r
- "Return the height (in screen lines) of the buffer that WINDOW is displaying."\r
- (with-current-buffer (window-buffer window)\r
- (max 1\r
- (count-screen-lines (point-min) (point-max)\r
- ;; If buffer ends with a newline, ignore it when\r
- ;; counting height unless point is after it.\r
- (eobp)\r
- window))))\r
-\r
-(defun count-screen-lines (&optional beg end count-final-newline window)\r
- "Return the number of screen lines in the region.\r
-The number of screen lines may be different from the number of actual lines,\r
-due to line breaking, display table, etc.\r
-\r
-Optional arguments BEG and END default to `point-min' and `point-max'\r
-respectively.\r
-\r
-If region ends with a newline, ignore it unless optional third argument\r
-COUNT-FINAL-NEWLINE is non-nil.\r
-\r
-The optional fourth argument WINDOW specifies the window used for obtaining\r
-parameters such as width, horizontal scrolling, and so on. The default is\r
-to use the selected window's parameters.\r
-\r
-Like `vertical-motion', `count-screen-lines' always uses the current buffer,\r
-regardless of which buffer is displayed in WINDOW. This makes possible to use\r
-`count-screen-lines' in any buffer, whether or not it is currently displayed\r
-in some window."\r
- (unless beg\r
- (setq beg (point-min)))\r
- (unless end\r
- (setq end (point-max)))\r
- (if (= beg end)\r
- 0\r
- (save-excursion\r
- (save-restriction\r
- (widen)\r
- (narrow-to-region (min beg end)\r
- (if (and (not count-final-newline)\r
- (= ?\n (char-before (max beg end))))\r
- (1- (max beg end))\r
- (max beg end)))\r
- (goto-char (point-min))\r
- (1+ (vertical-motion (buffer-size) window))))))\r
-\r
-(defun fit-window-to-buffer (&optional window max-height min-height)\r
- "Adjust height of WINDOW to display its buffer's contents exactly.\r
-WINDOW defaults to the selected window.\r
-Optional argument MAX-HEIGHT specifies the maximum height of the\r
-window and defaults to the height of WINDOW's frame.\r
-Optional argument MIN-HEIGHT specifies the minimum height of the\r
-window and defaults to `window-min-height'.\r
-Both, MAX-HEIGHT and MIN-HEIGHT are specified in lines and\r
-include the mode line and header line, if any.\r
-Always return nil."\r
- (interactive)\r
-\r
- (when (null window)\r
- (setq window (selected-window)))\r
- (when (null max-height)\r
- (setq max-height (frame-height (window-frame window))))\r
-\r
- (let* ((buf\r
- ;; Buffer that is displayed in WINDOW\r
- (window-buffer window))\r
- (window-height\r
- ;; The current height of WINDOW\r
- (window-height window))\r
- (desired-height\r
- ;; The height necessary to show the buffer displayed by WINDOW\r
- ;; (`count-screen-lines' always works on the current buffer).\r
- (with-current-buffer buf\r
- (+ (count-screen-lines)\r
- ;; If the buffer is empty, (count-screen-lines) is\r
- ;; zero. But, even in that case, we need one text line\r
- ;; for cursor.\r
- (if (= (point-min) (point-max))\r
- 1 0)\r
- ;; For non-minibuffers, count the mode-line, if any\r
- (if (and (not (window-minibuffer-p window))\r
- mode-line-format)\r
- 1 0)\r
- ;; Count the header-line, if any\r
- (if header-line-format 1 0))))\r
- (delta\r
- ;; Calculate how much the window height has to change to show\r
- ;; desired-height lines, constrained by MIN-HEIGHT and MAX-HEIGHT.\r
- (- (max (min desired-height max-height)\r
- (or min-height window-min-height))\r
- window-height)))\r
-\r
- ;; Don't try to redisplay with the cursor at the end\r
- ;; on its own line--that would force a scroll and spoil things.\r
- (when (with-current-buffer buf\r
- (and (eobp) (bolp) (not (bobp))))\r
- (set-window-point window (1- (window-point window))))\r
-\r
- (save-selected-window\r
- (select-window window 'norecord)\r
-\r
- ;; Adjust WINDOW to the nominally correct size (which may actually\r
- ;; be slightly off because of variable height text, etc).\r
- (unless (zerop delta)\r
- (enlarge-window delta))\r
-\r
- ;; Check if the last line is surely fully visible. If not,\r
- ;; enlarge the window.\r
- (let ((end (with-current-buffer buf\r
- (save-excursion\r
- (goto-char (point-max))\r
- (when (and (bolp) (not (bobp)))\r
- ;; Don't include final newline\r
- (backward-char 1))\r
- (when truncate-lines\r
- ;; If line-wrapping is turned off, test the\r
- ;; beginning of the last line for visibility\r
- ;; instead of the end, as the end of the line\r
- ;; could be invisible by virtue of extending past\r
- ;; the edge of the window.\r
- (forward-line 0))\r
- (point)))))\r
- (set-window-vscroll window 0)\r
- (while (and (< desired-height max-height)\r
- (= desired-height (window-height window))\r
- (not (pos-visible-in-window-p end window)))\r
- (enlarge-window 1)\r
- (setq desired-height (1+ desired-height)))))))\r
-\r
-(defun window-safely-shrinkable-p (&optional window)\r
- "Return t if WINDOW can be shrunk without shrinking other windows.\r
-WINDOW defaults to the selected window."\r
- (with-selected-window (or window (selected-window))\r
- (let ((edges (window-edges)))\r
- (or (= (nth 2 edges) (nth 2 (window-edges (previous-window))))\r
- (= (nth 0 edges) (nth 0 (window-edges (next-window))))))))\r
-\r
-(defun shrink-window-if-larger-than-buffer (&optional window)\r
- "Shrink height of WINDOW if its buffer doesn't need so many lines.\r
-More precisely, shrink WINDOW vertically to be as small as\r
-possible, while still showing the full contents of its buffer.\r
-WINDOW defaults to the selected window.\r
-\r
-Do not shrink to less than `window-min-height' lines. Do nothing\r
-if the buffer contains more lines than the present window height,\r
-or if some of the window's contents are scrolled out of view, or\r
-if shrinking this window would also shrink another window, or if\r
-the window is the only window of its frame.\r
-\r
-Return non-nil if the window was shrunk, nil otherwise."\r
- (interactive)\r
- (when (null window)\r
- (setq window (selected-window)))\r
- (let* ((frame (window-frame window))\r
- (mini (frame-parameter frame 'minibuffer))\r
- (edges (window-edges window)))\r
- (if (and (not (eq window (frame-root-window frame)))\r
- (window-safely-shrinkable-p window)\r
- (pos-visible-in-window-p (point-min) window)\r
- (not (eq mini 'only))\r
- (or (not mini)\r
- (let ((mini-window (minibuffer-window frame)))\r
- (or (null mini-window)\r
- (not (eq frame (window-frame mini-window)))\r
- (< (nth 3 edges)\r
- (nth 1 (window-edges mini-window)))\r
- (> (nth 1 edges)\r
- (frame-parameter frame 'menu-bar-lines))))))\r
- (fit-window-to-buffer window (window-height window)))))\r
-\r
-(defun kill-buffer-and-window ()\r
- "Kill the current buffer and delete the selected window."\r
- (interactive)\r
- (let ((window-to-delete (selected-window))\r
- (buffer-to-kill (current-buffer))\r
- (delete-window-hook (lambda ()\r
- (condition-case nil\r
- (delete-window)\r
- (error nil)))))\r
- (unwind-protect\r
- (progn\r
- (add-hook 'kill-buffer-hook delete-window-hook t t)\r
- (if (kill-buffer (current-buffer))\r
- ;; If `delete-window' failed before, we rerun it to regenerate\r
- ;; the error so it can be seen in the echo area.\r
- (when (eq (selected-window) window-to-delete)\r
- (delete-window))))\r
- ;; If the buffer is not dead for some reason (probably because\r
- ;; of a `quit' signal), remove the hook again.\r
- (condition-case nil\r
- (with-current-buffer buffer-to-kill\r
- (remove-hook 'kill-buffer-hook delete-window-hook t))\r
- (error nil)))))\r
-\r
-(defun quit-window (&optional kill window)\r
- "Quit WINDOW and bury its buffer.\r
-With a prefix argument, kill the buffer instead. WINDOW defaults\r
-to the selected window.\r
-\r
-If WINDOW is non-nil, dedicated, or a minibuffer window, delete\r
-it and, if it's alone on its frame, its frame too. Otherwise, or\r
-if deleting WINDOW fails in any of the preceding cases, display\r
-another buffer in WINDOW using `switch-to-buffer'.\r
-\r
-Optional argument KILL non-nil means kill WINDOW's buffer.\r
-Otherwise, bury WINDOW's buffer, see `bury-buffer'."\r
- (interactive "P")\r
- (let ((buffer (window-buffer window)))\r
- (if (or window\r
- (window-minibuffer-p window)\r
- (window-dedicated-p window))\r
- ;; WINDOW is either non-nil, a minibuffer window, or dedicated;\r
- ;; try to delete it.\r
- (let ((frame (window-frame (or window (selected-window)))))\r
- (if (eq window (frame-root-window frame))\r
- ;; WINDOW is alone on its frame. `delete-windows-on'\r
- ;; knows how to handle that case.\r
- (delete-windows-on buffer frame)\r
- ;; There are other windows on its frame, delete WINDOW.\r
- (delete-window window)))\r
- ;; Otherwise, switch to another buffer in the selected window.\r
- (switch-to-buffer nil))\r
-\r
- ;; Deal with the buffer.\r
- (if kill\r
- (kill-buffer buffer)\r
- (bury-buffer buffer))))\r
-\r
-(defvar recenter-last-op nil\r
- "Indicates the last recenter operation performed.\r
-Possible values: `top', `middle', `bottom'.")\r
-\r
-(defun recenter-top-bottom (&optional arg)\r
- "Move current line to window center, top, and bottom, successively.\r
-With no prefix argument, the first call redraws the frame and\r
- centers point vertically within the window. Successive calls\r
- scroll the window, placing point on the top, bottom, and middle\r
- consecutively. The cycling order is middle -> top -> bottom.\r
-\r
-A prefix argument is handled like `recenter':\r
- With numeric prefix ARG, move current line to window-line ARG.\r
- With plain `C-u', move current line to window center.\r
-\r
-Top and bottom destinations are actually `scroll-margin' lines\r
- the from true window top and bottom."\r
- (interactive "P")\r
- (cond\r
- (arg (recenter arg)) ; Always respect ARG.\r
- ((or (not (eq this-command last-command))\r
- (eq recenter-last-op 'bottom))\r
- (setq recenter-last-op 'middle)\r
- (recenter))\r
- (t\r
- (let ((this-scroll-margin\r
- (min (max 0 scroll-margin)\r
- (truncate (/ (window-body-height) 4.0)))))\r
- (cond ((eq recenter-last-op 'middle)\r
- (setq recenter-last-op 'top)\r
- (recenter this-scroll-margin))\r
- ((eq recenter-last-op 'top)\r
- (setq recenter-last-op 'bottom)\r
- (recenter (- -1 this-scroll-margin))))))))\r
-\r
-(define-key global-map [?\C-l] 'recenter-top-bottom)\r
-\f\r
-(defvar mouse-autoselect-window-timer nil\r
- "Timer used by delayed window autoselection.")\r
-\r
-(defvar mouse-autoselect-window-position nil\r
- "Last mouse position recorded by delayed window autoselection.")\r
-\r
-(defvar mouse-autoselect-window-window nil\r
- "Last window recorded by delayed window autoselection.")\r
-\r
-(defvar mouse-autoselect-window-state nil\r
- "When non-nil, special state of delayed window autoselection.\r
-Possible values are `suspend' \(suspend autoselection after a menu or\r
-scrollbar interaction\) and `select' \(the next invocation of\r
-'handle-select-window' shall select the window immediately\).")\r
-\r
-(defun mouse-autoselect-window-cancel (&optional force)\r
- "Cancel delayed window autoselection.\r
-Optional argument FORCE means cancel unconditionally."\r
- (unless (and (not force)\r
- ;; Don't cancel for select-window or select-frame events\r
- ;; or when the user drags a scroll bar.\r
- (or (memq this-command\r
- '(handle-select-window handle-switch-frame))\r
- (and (eq this-command 'scroll-bar-toolkit-scroll)\r
- (memq (nth 4 (event-end last-input-event))\r
- '(handle end-scroll)))))\r
- (setq mouse-autoselect-window-state nil)\r
- (when (timerp mouse-autoselect-window-timer)\r
- (cancel-timer mouse-autoselect-window-timer))\r
- (remove-hook 'pre-command-hook 'mouse-autoselect-window-cancel)))\r
-\r
-(defun mouse-autoselect-window-start (mouse-position &optional window suspend)\r
- "Start delayed window autoselection.\r
-MOUSE-POSITION is the last position where the mouse was seen as returned\r
-by `mouse-position'. Optional argument WINDOW non-nil denotes the\r
-window where the mouse was seen. Optional argument SUSPEND non-nil\r
-means suspend autoselection."\r
- ;; Record values for MOUSE-POSITION, WINDOW, and SUSPEND.\r
- (setq mouse-autoselect-window-position mouse-position)\r
- (when window (setq mouse-autoselect-window-window window))\r
- (setq mouse-autoselect-window-state (when suspend 'suspend))\r
- ;; Install timer which runs `mouse-autoselect-window-select' after\r
- ;; `mouse-autoselect-window' seconds.\r
- (setq mouse-autoselect-window-timer\r
- (run-at-time\r
- (abs mouse-autoselect-window) nil 'mouse-autoselect-window-select)))\r
-\r
-(defun mouse-autoselect-window-select ()\r
- "Select window with delayed window autoselection.\r
-If the mouse position has stabilized in a non-selected window, select\r
-that window. The minibuffer window is selected only if the minibuffer is\r
-active. This function is run by `mouse-autoselect-window-timer'."\r
- (condition-case nil\r
- (let* ((mouse-position (mouse-position))\r
- (window\r
- (condition-case nil\r
- (window-at (cadr mouse-position) (cddr mouse-position)\r
- (car mouse-position))\r
- (error nil))))\r
- (cond\r
- ((or (menu-or-popup-active-p)\r
- (and window\r
- (not (coordinates-in-window-p (cdr mouse-position) window))))\r
- ;; A menu / popup dialog is active or the mouse is on the scroll-bar\r
- ;; of WINDOW, temporarily suspend delayed autoselection.\r
- (mouse-autoselect-window-start mouse-position nil t))\r
- ((eq mouse-autoselect-window-state 'suspend)\r
- ;; Delayed autoselection was temporarily suspended, reenable it.\r
- (mouse-autoselect-window-start mouse-position))\r
- ((and window (not (eq window (selected-window)))\r
- (or (not (numberp mouse-autoselect-window))\r
- (and (> mouse-autoselect-window 0)\r
- ;; If `mouse-autoselect-window' is positive, select\r
- ;; window if the window is the same as before.\r
- (eq window mouse-autoselect-window-window))\r
- ;; Otherwise select window if the mouse is at the same\r
- ;; position as before. Observe that the first test after\r
- ;; starting autoselection usually fails since the value of\r
- ;; `mouse-autoselect-window-position' recorded there is the\r
- ;; position where the mouse has entered the new window and\r
- ;; not necessarily where the mouse has stopped moving.\r
- (equal mouse-position mouse-autoselect-window-position))\r
- ;; The minibuffer is a candidate window if it's active.\r
- (or (not (window-minibuffer-p window))\r
- (eq window (active-minibuffer-window))))\r
- ;; Mouse position has stabilized in non-selected window: Cancel\r
- ;; delayed autoselection and try to select that window.\r
- (mouse-autoselect-window-cancel t)\r
- ;; Select window where mouse appears unless the selected window is the\r
- ;; minibuffer. Use `unread-command-events' in order to execute pre-\r
- ;; and post-command hooks and trigger idle timers. To avoid delaying\r
- ;; autoselection again, set `mouse-autoselect-window-state'."\r
- (unless (window-minibuffer-p (selected-window))\r
- (setq mouse-autoselect-window-state 'select)\r
- (setq unread-command-events\r
- (cons (list 'select-window (list window))\r
- unread-command-events))))\r
- ((or (and window (eq window (selected-window)))\r
- (not (numberp mouse-autoselect-window))\r
- (equal mouse-position mouse-autoselect-window-position))\r
- ;; Mouse position has either stabilized in the selected window or at\r
- ;; `mouse-autoselect-window-position': Cancel delayed autoselection.\r
- (mouse-autoselect-window-cancel t))\r
- (t\r
- ;; Mouse position has not stabilized yet, resume delayed\r
- ;; autoselection.\r
- (mouse-autoselect-window-start mouse-position window))))\r
- (error nil)))\r
-\r
-(defun handle-select-window (event)\r
- "Handle select-window events."\r
- (interactive "e")\r
- (let ((window (posn-window (event-start event))))\r
- (unless (or (not (window-live-p window))\r
- ;; Don't switch if we're currently in the minibuffer.\r
- ;; This tries to work around problems where the\r
- ;; minibuffer gets unselected unexpectedly, and where\r
- ;; you then have to move your mouse all the way down to\r
- ;; the minibuffer to select it.\r
- (window-minibuffer-p (selected-window))\r
- ;; Don't switch to minibuffer window unless it's active.\r
- (and (window-minibuffer-p window)\r
- (not (minibuffer-window-active-p window)))\r
- ;; Don't switch when autoselection shall be delayed.\r
- (and (numberp mouse-autoselect-window)\r
- (not (zerop mouse-autoselect-window))\r
- (not (eq mouse-autoselect-window-state 'select))\r
- (progn\r
- ;; Cancel any delayed autoselection.\r
- (mouse-autoselect-window-cancel t)\r
- ;; Start delayed autoselection from current mouse\r
- ;; position and window.\r
- (mouse-autoselect-window-start (mouse-position) window)\r
- ;; Executing a command cancels delayed autoselection.\r
- (add-hook\r
- 'pre-command-hook 'mouse-autoselect-window-cancel))))\r
- (when mouse-autoselect-window\r
- ;; Reset state of delayed autoselection.\r
- (setq mouse-autoselect-window-state nil)\r
- ;; Run `mouse-leave-buffer-hook' when autoselecting window.\r
- (run-hooks 'mouse-leave-buffer-hook))\r
- (select-window window))))\r
-\r
-(defun delete-other-windows-vertically (&optional window)\r
- "Delete the windows in the same column with WINDOW, but not WINDOW itself.\r
-This may be a useful alternative binding for \\[delete-other-windows]\r
- if you often split windows horizontally."\r
- (interactive)\r
- (let* ((window (or window (selected-window)))\r
- (edges (window-edges window))\r
- (w window) delenda)\r
- (while (not (eq (setq w (next-window w 1)) window))\r
- (let ((e (window-edges w)))\r
- (when (and (= (car e) (car edges))\r
- (= (caddr e) (caddr edges)))\r
- (push w delenda))))\r
- (mapc 'delete-window delenda)))\r
-\r
-(defun truncated-partial-width-window-p (&optional window)\r
- "Return non-nil if lines in WINDOW are specifically truncated due to its width.\r
-WINDOW defaults to the selected window.\r
-Return nil if WINDOW is not a partial-width window\r
- (regardless of the value of `truncate-lines').\r
-Otherwise, consult the value of `truncate-partial-width-windows'\r
- for the buffer shown in WINDOW."\r
- (unless window\r
- (setq window (selected-window)))\r
- (unless (window-full-width-p window)\r
- (let ((t-p-w-w (buffer-local-value 'truncate-partial-width-windows\r
- (window-buffer window))))\r
- (if (integerp t-p-w-w)\r
- (< (window-width window) t-p-w-w)\r
- t-p-w-w))))\r
-\r
-(define-key ctl-x-map "2" 'split-window-vertically)\r
-(define-key ctl-x-map "3" 'split-window-horizontally)\r
-(define-key ctl-x-map "}" 'enlarge-window-horizontally)\r
-(define-key ctl-x-map "{" 'shrink-window-horizontally)\r
-(define-key ctl-x-map "-" 'shrink-window-if-larger-than-buffer)\r
-(define-key ctl-x-map "+" 'balance-windows)\r
-(define-key ctl-x-4-map "0" 'kill-buffer-and-window)\r
-\r
-;; arch-tag: b508dfcc-c353-4c37-89fa-e773fe10cea9\r
-;;; window.el ends here\r
+;;; window.el --- GNU Emacs window commands aside from those written in C
+
+;; Copyright (C) 1985, 1989, 1992, 1993, 1994, 2000, 2001, 2002,
+;; 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
+
+;; Maintainer: FSF
+;; Keywords: internal
+
+;; 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 <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; Window tree functions.
+
+;;; Code:
+
+(eval-when-compile (require 'cl))
+
+(defvar window-size-fixed nil
+ "*Non-nil in a buffer means windows displaying the buffer are fixed-size.
+If the value is `height', then only the window's height is fixed.
+If the value is `width', then only the window's width is fixed.
+Any other non-nil value fixes both the width and the height.
+Emacs won't change the size of any window displaying that buffer,
+unless you explicitly change the size, or Emacs has no other choice.")
+(make-variable-buffer-local 'window-size-fixed)
+
+(defmacro save-selected-window (&rest body)
+ "Execute BODY, then select the previously selected window.
+The value returned is the value of the last form in BODY.
+
+This macro saves and restores the selected window, as well as the
+selected window in each frame. If the previously selected window
+is no longer live, then whatever window is selected at the end of
+BODY remains selected. If the previously selected window of some
+frame is no longer live at the end of BODY, that frame's selected
+window is left alone.
+
+This macro saves and restores the current buffer, since otherwise
+its normal operation could make a different buffer current. The
+order of recently selected windows and the buffer list ordering
+are not altered by this macro (unless they are altered in BODY)."
+ `(let ((save-selected-window-window (selected-window))
+ ;; It is necessary to save all of these, because calling
+ ;; select-window changes frame-selected-window for whatever
+ ;; frame that window is in.
+ (save-selected-window-alist
+ (mapcar (lambda (frame) (cons frame (frame-selected-window frame)))
+ (frame-list))))
+ (save-current-buffer
+ (unwind-protect
+ (progn ,@body)
+ (dolist (elt save-selected-window-alist)
+ (and (frame-live-p (car elt))
+ (window-live-p (cdr elt))
+ (set-frame-selected-window (car elt) (cdr elt) 'norecord)))
+ (when (window-live-p save-selected-window-window)
+ (select-window save-selected-window-window 'norecord))))))
+
+(defun window-body-height (&optional window)
+ "Return number of lines in WINDOW available for actual buffer text.
+WINDOW defaults to the selected window.
+
+The return value does not include the mode line or the header
+line, if any. If a line at the bottom of the window is only
+partially visible, that line is included in the return value. If
+you do not want to include a partially visible bottom line in the
+return value, use `window-text-height' instead."
+ (or window (setq window (selected-window)))
+ (if (window-minibuffer-p window)
+ (window-height window)
+ (with-current-buffer (window-buffer window)
+ (max 1 (- (window-height window)
+ (if mode-line-format 1 0)
+ (if header-line-format 1 0))))))
+
+(defun one-window-p (&optional nomini all-frames)
+ "Return non-nil if the selected window is the only window.
+Optional arg NOMINI non-nil means don't count the minibuffer
+even if it is active. Otherwise, the minibuffer is counted
+when it is active.
+
+The optional arg ALL-FRAMES t means count windows on all frames.
+If it is `visible', count windows on all visible frames.
+ALL-FRAMES nil or omitted means count only the selected frame,
+plus the minibuffer it uses (which may be on another frame).
+ALL-FRAMES 0 means count all windows in all visible or iconified frames.
+If ALL-FRAMES is anything else, count only the selected frame."
+ (let ((base-window (selected-window)))
+ (if (and nomini (eq base-window (minibuffer-window)))
+ (setq base-window (next-window base-window)))
+ (eq base-window
+ (next-window base-window (if nomini 'arg) all-frames))))
+
+(defun window-current-scroll-bars (&optional window)
+ "Return the current scroll bar settings for WINDOW.
+WINDOW defaults to the selected window.
+
+The return value is a cons cell (VERTICAL . HORIZONTAL) where
+VERTICAL specifies the current location of the vertical scroll
+bars (`left', `right', or nil), and HORIZONTAL specifies the
+current location of the horizontal scroll bars (`top', `bottom',
+or nil).
+
+Unlike `window-scroll-bars', this function reports the scroll bar
+type actually used, once frame defaults and `scroll-bar-mode' are
+taken into account."
+ (let ((vert (nth 2 (window-scroll-bars window)))
+ (hor nil))
+ (when (or (eq vert t) (eq hor t))
+ (let ((fcsb (frame-current-scroll-bars
+ (window-frame (or window (selected-window))))))
+ (if (eq vert t)
+ (setq vert (car fcsb)))
+ (if (eq hor t)
+ (setq hor (cdr fcsb)))))
+ (cons vert hor)))
+
+(defun walk-windows (proc &optional minibuf all-frames)
+ "Cycle through all windows, calling PROC for each one.
+PROC must specify a function with a window as its sole argument.
+The optional arguments MINIBUF and ALL-FRAMES specify the set of
+windows to include in the walk, see also `next-window'.
+
+MINIBUF t means include the minibuffer window even if the
+minibuffer is not active. MINIBUF nil or omitted means include
+the minibuffer window only if the minibuffer is active. Any
+other value means do not include the minibuffer window even if
+the minibuffer is active.
+
+Several frames may share a single minibuffer; if the minibuffer
+is active, all windows on all frames that share that minibuffer
+are included too. Therefore, if you are using a separate
+minibuffer frame and the minibuffer is active and MINIBUF says it
+counts, `walk-windows' includes the windows in the frame from
+which you entered the minibuffer, as well as the minibuffer
+window.
+
+ALL-FRAMES nil or omitted means cycle through all windows on
+ WINDOW's frame, plus the minibuffer window if specified by the
+ MINIBUF argument, see above. If the minibuffer counts, cycle
+ through all windows on all frames that share that minibuffer
+ too.
+ALL-FRAMES t means cycle through all windows on all existing
+ frames.
+ALL-FRAMES `visible' means cycle through all windows on all
+ visible frames.
+ALL-FRAMES 0 means cycle through all windows on all visible and
+ iconified frames.
+ALL-FRAMES a frame means cycle through all windows on that frame
+ only.
+Anything else means cycle through all windows on WINDOW's frame
+ and no others.
+
+This function changes neither the order of recently selected
+windows nor the buffer list."
+ ;; If we start from the minibuffer window, don't fail to come
+ ;; back to it.
+ (when (window-minibuffer-p (selected-window))
+ (setq minibuf t))
+ ;; Make sure to not mess up the order of recently selected
+ ;; windows. Use `save-selected-window' and `select-window'
+ ;; with second argument non-nil for this purpose.
+ (save-selected-window
+ (when (framep all-frames)
+ (select-window (frame-first-window all-frames) 'norecord))
+ (let* (walk-windows-already-seen
+ (walk-windows-current (selected-window)))
+ (while (progn
+ (setq walk-windows-current
+ (next-window walk-windows-current minibuf all-frames))
+ (not (memq walk-windows-current walk-windows-already-seen)))
+ (setq walk-windows-already-seen
+ (cons walk-windows-current walk-windows-already-seen))
+ (funcall proc walk-windows-current)))))
+
+(defun get-window-with-predicate (predicate &optional minibuf
+ all-frames default)
+ "Return a window satisfying PREDICATE.
+More precisely, cycle through all windows using `walk-windows',
+calling the function PREDICATE on each one of them with the
+window as its sole argument. Return the first window for which
+PREDICATE returns non-nil. If no window satisfies PREDICATE,
+return DEFAULT.
+
+The optional arguments MINIBUF and ALL-FRAMES specify the set of
+windows to include. See `walk-windows' for the meaning of these
+arguments."
+ (catch 'found
+ (walk-windows #'(lambda (window)
+ (when (funcall predicate window)
+ (throw 'found window)))
+ minibuf all-frames)
+ default))
+
+(defalias 'some-window 'get-window-with-predicate)
+
+;; This should probably be written in C (i.e., without using `walk-windows').
+(defun get-buffer-window-list (&optional buffer-or-name minibuf all-frames)
+ "Return list of all windows displaying BUFFER-OR-NAME, or nil if none.
+BUFFER-OR-NAME may be a buffer or the name of an existing buffer
+and defaults to the current buffer.
+
+The optional arguments MINIBUF and ALL-FRAMES specify the set of
+windows to consider. See `walk-windows' for the precise meaning
+of these arguments."
+ (let ((buffer (cond
+ ((not buffer-or-name) (current-buffer))
+ ((bufferp buffer-or-name) buffer-or-name)
+ (t (get-buffer buffer-or-name))))
+ windows)
+ (walk-windows (function (lambda (window)
+ (if (eq (window-buffer window) buffer)
+ (setq windows (cons window windows)))))
+ minibuf all-frames)
+ windows))
+
+(defun minibuffer-window-active-p (window)
+ "Return t if WINDOW is the currently active minibuffer window."
+ (eq window (active-minibuffer-window)))
+\f
+(defun count-windows (&optional minibuf)
+ "Return the number of visible windows.
+The optional argument MINIBUF specifies whether the minibuffer
+window shall be counted. See `walk-windows' for the precise
+meaning of this argument."
+ (let ((count 0))
+ (walk-windows (lambda (w) (setq count (+ count 1)))
+ minibuf)
+ count))
+\f
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;; `balance-windows' subroutines using `window-tree'
+
+;;; Translate from internal window tree format
+
+(defun bw-get-tree (&optional window-or-frame)
+ "Get a window split tree in our format.
+
+WINDOW-OR-FRAME must be nil, a frame, or a window. If it is nil,
+then the whole window split tree for `selected-frame' is returned.
+If it is a frame, then this is used instead. If it is a window,
+then the smallest tree containing that window is returned."
+ (when window-or-frame
+ (unless (or (framep window-or-frame)
+ (windowp window-or-frame))
+ (error "Not a frame or window: %s" window-or-frame)))
+ (let ((subtree (bw-find-tree-sub window-or-frame)))
+ (when subtree
+ (if (integerp subtree)
+ nil
+ (bw-get-tree-1 subtree)))))
+
+(defun bw-get-tree-1 (split)
+ (if (windowp split)
+ split
+ (let ((dir (car split))
+ (edges (car (cdr split)))
+ (childs (cdr (cdr split))))
+ (list
+ (cons 'dir (if dir 'ver 'hor))
+ (cons 'b (nth 3 edges))
+ (cons 'r (nth 2 edges))
+ (cons 't (nth 1 edges))
+ (cons 'l (nth 0 edges))
+ (cons 'childs (mapcar #'bw-get-tree-1 childs))))))
+
+(defun bw-find-tree-sub (window-or-frame &optional get-parent)
+ (let* ((window (when (windowp window-or-frame) window-or-frame))
+ (frame (when (windowp window) (window-frame window)))
+ (wt (car (window-tree frame))))
+ (when (< 1 (length (window-list frame 0)))
+ (if window
+ (bw-find-tree-sub-1 wt window get-parent)
+ wt))))
+
+(defun bw-find-tree-sub-1 (tree win &optional get-parent)
+ (unless (windowp win) (error "Not a window: %s" win))
+ (if (memq win tree)
+ (if get-parent
+ get-parent
+ tree)
+ (let ((childs (cdr (cdr tree)))
+ child
+ subtree)
+ (while (and childs (not subtree))
+ (setq child (car childs))
+ (setq childs (cdr childs))
+ (when (and child (listp child))
+ (setq subtree (bw-find-tree-sub-1 child win get-parent))))
+ (if (integerp subtree)
+ (progn
+ (if (= 1 subtree)
+ tree
+ (1- subtree)))
+ subtree
+ ))))
+
+;;; Window or object edges
+
+(defun bw-l (obj)
+ "Left edge of OBJ."
+ (if (windowp obj) (nth 0 (window-edges obj)) (cdr (assq 'l obj))))
+(defun bw-t (obj)
+ "Top edge of OBJ."
+ (if (windowp obj) (nth 1 (window-edges obj)) (cdr (assq 't obj))))
+(defun bw-r (obj)
+ "Right edge of OBJ."
+ (if (windowp obj) (nth 2 (window-edges obj)) (cdr (assq 'r obj))))
+(defun bw-b (obj)
+ "Bottom edge of OBJ."
+ (if (windowp obj) (nth 3 (window-edges obj)) (cdr (assq 'b obj))))
+
+;;; Split directions
+
+(defun bw-dir (obj)
+ "Return window split tree direction if OBJ.
+If OBJ is a window return 'both. If it is a window split tree
+then return its direction."
+ (if (symbolp obj)
+ obj
+ (if (windowp obj)
+ 'both
+ (let ((dir (cdr (assq 'dir obj))))
+ (unless (memq dir '(hor ver both))
+ (error "Can't find dir in %s" obj))
+ dir))))
+
+(defun bw-eqdir (obj1 obj2)
+ "Return t if window split tree directions are equal.
+OBJ1 and OBJ2 should be either windows or window split trees in
+our format. The directions returned by `bw-dir' are compared and
+t is returned if they are `eq' or one of them is 'both."
+ (let ((dir1 (bw-dir obj1))
+ (dir2 (bw-dir obj2)))
+ (or (eq dir1 dir2)
+ (eq dir1 'both)
+ (eq dir2 'both))))
+
+;;; Building split tree
+
+(defun bw-refresh-edges (obj)
+ "Refresh the edge information of OBJ and return OBJ."
+ (unless (windowp obj)
+ (let ((childs (cdr (assq 'childs obj)))
+ (ol 1000)
+ (ot 1000)
+ (or -1)
+ (ob -1))
+ (dolist (o childs)
+ (when (> ol (bw-l o)) (setq ol (bw-l o)))
+ (when (> ot (bw-t o)) (setq ot (bw-t o)))
+ (when (< or (bw-r o)) (setq or (bw-r o)))
+ (when (< ob (bw-b o)) (setq ob (bw-b o))))
+ (setq obj (delq 'l obj))
+ (setq obj (delq 't obj))
+ (setq obj (delq 'r obj))
+ (setq obj (delq 'b obj))
+ (add-to-list 'obj (cons 'l ol))
+ (add-to-list 'obj (cons 't ot))
+ (add-to-list 'obj (cons 'r or))
+ (add-to-list 'obj (cons 'b ob))
+ ))
+ obj)
+
+;;; Balance windows
+
+(defun balance-windows (&optional window-or-frame)
+ "Make windows the same heights or widths in window split subtrees.
+
+When called non-interactively WINDOW-OR-FRAME may be either a
+window or a frame. It then balances the windows on the implied
+frame. If the parameter is a window only the corresponding window
+subtree is balanced."
+ (interactive)
+ (let (
+ (wt (bw-get-tree window-or-frame))
+ (w)
+ (h)
+ (tried-sizes)
+ (last-sizes)
+ (windows (window-list nil 0)))
+ (when wt
+ (while (not (member last-sizes tried-sizes))
+ (when last-sizes (setq tried-sizes (cons last-sizes tried-sizes)))
+ (setq last-sizes (mapcar (lambda (w)
+ (window-edges w))
+ windows))
+ (when (eq 'hor (bw-dir wt))
+ (setq w (- (bw-r wt) (bw-l wt))))
+ (when (eq 'ver (bw-dir wt))
+ (setq h (- (bw-b wt) (bw-t wt))))
+ (bw-balance-sub wt w h)))))
+
+(defun bw-adjust-window (window delta horizontal)
+ "Wrapper around `adjust-window-trailing-edge' with error checking.
+Arguments WINDOW, DELTA and HORIZONTAL are passed on to that function."
+ ;; `adjust-window-trailing-edge' may fail if delta is too large.
+ (while (>= (abs delta) 1)
+ (condition-case err
+ (progn
+ (adjust-window-trailing-edge window delta horizontal)
+ (setq delta 0))
+ (error
+ ;;(message "adjust: %s" (error-message-string err))
+ (setq delta (/ delta 2))))))
+
+(defun bw-balance-sub (wt w h)
+ (setq wt (bw-refresh-edges wt))
+ (unless w (setq w (- (bw-r wt) (bw-l wt))))
+ (unless h (setq h (- (bw-b wt) (bw-t wt))))
+ (if (windowp wt)
+ (progn
+ (when w
+ (let ((dw (- w (- (bw-r wt) (bw-l wt)))))
+ (when (/= 0 dw)
+ (bw-adjust-window wt dw t))))
+ (when h
+ (let ((dh (- h (- (bw-b wt) (bw-t wt)))))
+ (when (/= 0 dh)
+ (bw-adjust-window wt dh nil)))))
+ (let* ((childs (cdr (assq 'childs wt)))
+ (cw (when w (/ w (if (bw-eqdir 'hor wt) (length childs) 1))))
+ (ch (when h (/ h (if (bw-eqdir 'ver wt) (length childs) 1)))))
+ (dolist (c childs)
+ (bw-balance-sub c cw ch)))))
+
+(defun window-fixed-size-p (&optional window direction)
+ "Return t if WINDOW cannot be resized in DIRECTION.
+WINDOW defaults to the selected window. DIRECTION can be
+nil (i.e. any), `height' or `width'."
+ (with-current-buffer (window-buffer window)
+ (when (and (boundp 'window-size-fixed) window-size-fixed)
+ (not (and direction
+ (member (cons direction window-size-fixed)
+ '((height . width) (width . height))))))))
+
+;;; A different solution to balance-windows.
+
+(defvar window-area-factor 1
+ "Factor by which the window area should be over-estimated.
+This is used by `balance-windows-area'.
+Changing this globally has no effect.")
+(make-variable-buffer-local 'window-area-factor)
+
+(defun balance-windows-area ()
+ "Make all visible windows the same area (approximately).
+See also `window-area-factor' to change the relative size of
+specific buffers."
+ (interactive)
+ (let* ((unchanged 0) (carry 0) (round 0)
+ ;; Remove fixed-size windows.
+ (wins (delq nil (mapcar (lambda (win)
+ (if (not (window-fixed-size-p win)) win))
+ (window-list nil 'nomini))))
+ (changelog nil)
+ next)
+ ;; Resizing a window changes the size of surrounding windows in complex
+ ;; ways, so it's difficult to balance them all. The introduction of
+ ;; `adjust-window-trailing-edge' made it a bit easier, but it is still
+ ;; very difficult to do. `balance-window' above takes an off-line
+ ;; approach: get the whole window tree, then balance it, then try to
+ ;; adjust the windows so they fit the result.
+ ;; Here, instead, we take a "local optimization" approach, where we just
+ ;; go through all the windows several times until nothing needs to be
+ ;; changed. The main problem with this approach is that it's difficult
+ ;; to make sure it terminates, so we use some heuristic to try and break
+ ;; off infinite loops.
+ ;; After a round without any change, we allow a second, to give a chance
+ ;; to the carry to propagate a minor imbalance from the end back to
+ ;; the beginning.
+ (while (< unchanged 2)
+ ;; (message "New round")
+ (setq unchanged (1+ unchanged) round (1+ round))
+ (dolist (win wins)
+ (setq next win)
+ (while (progn (setq next (next-window next))
+ (window-fixed-size-p next)))
+ ;; (assert (eq next (or (cadr (member win wins)) (car wins))))
+ (let* ((horiz
+ (< (car (window-edges win)) (car (window-edges next))))
+ (areadiff (/ (- (* (window-height next) (window-width next)
+ (buffer-local-value 'window-area-factor
+ (window-buffer next)))
+ (* (window-height win) (window-width win)
+ (buffer-local-value 'window-area-factor
+ (window-buffer win))))
+ (max (buffer-local-value 'window-area-factor
+ (window-buffer win))
+ (buffer-local-value 'window-area-factor
+ (window-buffer next)))))
+ (edgesize (if horiz
+ (+ (window-height win) (window-height next))
+ (+ (window-width win) (window-width next))))
+ (diff (/ areadiff edgesize)))
+ (when (zerop diff)
+ ;; Maybe diff is actually closer to 1 than to 0.
+ (setq diff (/ (* 3 areadiff) (* 2 edgesize))))
+ (when (and (zerop diff) (not (zerop areadiff)))
+ (setq diff (/ (+ areadiff carry) edgesize))
+ ;; Change things smoothly.
+ (if (or (> diff 1) (< diff -1)) (setq diff (/ diff 2))))
+ (if (zerop diff)
+ ;; Make sure negligible differences don't accumulate to
+ ;; become significant.
+ (setq carry (+ carry areadiff))
+ (bw-adjust-window win diff horiz)
+ ;; (sit-for 0.5)
+ (let ((change (cons win (window-edges win))))
+ ;; If the same change has been seen already for this window,
+ ;; we're most likely in an endless loop, so don't count it as
+ ;; a change.
+ (unless (member change changelog)
+ (push change changelog)
+ (setq unchanged 0 carry 0)))))))
+ ;; We've now basically balanced all the windows.
+ ;; But there may be some minor off-by-one imbalance left over,
+ ;; so let's do some fine tuning.
+ ;; (bw-finetune wins)
+ ;; (message "Done in %d rounds" round)
+ ))
+
+\f
+(defcustom display-buffer-function nil
+ "If non-nil, function to call to handle `display-buffer'.
+It will receive two args, the buffer and a flag which if non-nil
+means that the currently selected window is not acceptable. It
+should choose or create a window, display the specified buffer in
+it, and return the window.
+
+Commands such as `switch-to-buffer-other-window' and
+`find-file-other-window' work using this function."
+ :type '(choice
+ (const nil)
+ (function :tag "function"))
+ :group 'windows)
+
+(defun special-display-p (buffer-name)
+ "Return non-nil if a buffer named BUFFER-NAME gets a special frame.
+If the value is t, `display-buffer' or `pop-to-buffer' would
+create a special frame for that buffer using the default frame
+parameters.
+
+If the value is a list, it is a list of frame parameters that
+would be used to make a frame for that buffer. The variables
+`special-display-buffer-names' and `special-display-regexps'
+control this."
+ (let (tmp)
+ (cond
+ ((not (stringp buffer-name)))
+ ;; Make sure to return t in the following two cases.
+ ((member buffer-name special-display-buffer-names) t)
+ ((setq tmp (assoc buffer-name special-display-buffer-names)) (cdr tmp))
+ ((catch 'found
+ (dolist (regexp special-display-regexps)
+ (cond
+ ((stringp regexp)
+ (when (string-match-p regexp buffer-name)
+ (throw 'found t)))
+ ((and (consp regexp) (stringp (car regexp))
+ (string-match-p (car regexp) buffer-name))
+ (throw 'found (cdr regexp))))))))))
+
+(defcustom special-display-buffer-names nil
+ "List of buffer names that should have their own special frames.
+Displaying a buffer with `display-buffer' or `pop-to-buffer', if
+its name is in this list, makes a special frame for it using
+`special-display-function'. See also `special-display-regexps'.
+
+An element of the list can be a list instead of just a string.
+There are two ways to use a list as an element:
+ (BUFFER FRAME-PARAMETERS...) (BUFFER FUNCTION OTHER-ARGS...)
+In the first case, the FRAME-PARAMETERS are pairs of the form
+\(PARAMETER . VALUE); these parameter values are used to create
+the frame. In the second case, FUNCTION is called with BUFFER as
+the first argument, followed by the OTHER-ARGS--it can display
+BUFFER in any way it likes. All this is done by the function
+found in `special-display-function'.
+
+If the specified frame parameters include (same-buffer . t), the
+buffer is displayed in the currently selected window. Otherwise, if
+they include (same-frame . t), the buffer is displayed in a new window
+in the currently selected frame.
+
+If this variable appears \"not to work\", because you add a name to it
+but that buffer still appears in the selected window, look at the
+values of `same-window-buffer-names' and `same-window-regexps'.
+Those variables take precedence over this one."
+ :type '(repeat (choice :tag "Buffer"
+ :value ""
+ (string :format "%v")
+ (cons :tag "With attributes"
+ :format "%v"
+ :value ("" . nil)
+ (string :format "%v")
+ (repeat :tag "Attributes"
+ (cons :format "%v"
+ (symbol :tag "Parameter")
+ (sexp :tag "Value"))))))
+ :group 'frames)
+
+(defcustom special-display-regexps nil
+ "List of regexps saying which buffers should have their own special frames.
+When displaying a buffer with `display-buffer' or
+`pop-to-buffer', if any regexp in this list matches the buffer
+name, it makes a special frame for the buffer by calling
+`special-display-function'.
+
+An element of the list can be a list instead of just a string.
+There are two ways to use a list as an element:
+ (REGEXP FRAME-PARAMETERS...) (REGEXP FUNCTION OTHER-ARGS...)
+In the first case, the FRAME-PARAMETERS are pairs of the form
+\(PARAMETER . VALUE); these parameter values are used to create
+the frame. In the second case, FUNCTION is called with BUFFER as
+the first argument, followed by the OTHER-ARGS--it can display
+the buffer in any way it likes. All this is done by the function
+found in `special-display-function'.
+
+If the specified frame parameters include (same-buffer . t), the
+buffer is displayed in the currently selected window. Otherwise,
+if they include (same-frame . t), the buffer is displayed in a
+new window in the currently selected frame.
+
+If this variable appears \"not to work\", because you add a
+regexp to it but the matching buffers still appear in the
+selected window, look at the values of `same-window-buffer-names'
+and `same-window-regexps'. Those variables take precedence over
+this one."
+ :type '(repeat (choice :tag "Buffer"
+ :value ""
+ (regexp :format "%v")
+ (cons :tag "With attributes"
+ :format "%v"
+ :value ("" . nil)
+ (regexp :format "%v")
+ (repeat :tag "Attributes"
+ (cons :format "%v"
+ (symbol :tag "Parameter")
+ (sexp :tag "Value"))))))
+ :group 'frames)
+
+(defcustom special-display-function 'special-display-popup-frame
+ "Function to call to make a new frame for a special buffer.
+It is called with two arguments, the buffer and optional buffer
+specific data, and should return a window displaying that buffer.
+The default value normally makes a separate frame for the buffer,
+using `special-display-frame-alist' to specify the frame
+parameters.
+
+But if the buffer specific data includes (same-buffer . t) then
+the buffer is displayed in the current selected window.
+Otherwise if it includes (same-frame . t) then the buffer is
+displayed in a new window in the currently selected frame.
+
+A buffer is special if it is listed in
+`special-display-buffer-names' or matches a regexp in
+`special-display-regexps'."
+ :type 'function
+ :group 'frames)
+
+(defun same-window-p (buffer-name)
+ "Return non-nil if a buffer named BUFFER-NAME would be shown in the \"same\" window.
+This function returns non-nil if `display-buffer' or
+`pop-to-buffer' would show a buffer named BUFFER-NAME in the
+selected rather than \(as usual\) some other window. See
+`same-window-buffer-names' and `same-window-regexps'."
+ (cond
+ ((not (stringp buffer-name)))
+ ;; The elements of `same-window-buffer-names' can be buffer
+ ;; names or cons cells whose cars are buffer names.
+ ((member buffer-name same-window-buffer-names))
+ ((assoc buffer-name same-window-buffer-names))
+ ((catch 'found
+ (dolist (regexp same-window-regexps)
+ ;; The elements of `same-window-regexps' can be regexps
+ ;; or cons cells whose cars are regexps.
+ (when (or (and (stringp regexp)
+ (string-match regexp buffer-name))
+ (and (consp regexp) (stringp (car regexp))
+ (string-match-p (car regexp) buffer-name)))
+ (throw 'found t)))))))
+
+(defcustom same-window-buffer-names nil
+ "List of names of buffers that should appear in the \"same\" window.
+`display-buffer' and `pop-to-buffer' show a buffer whose name is
+on this list in the selected rather than some other window.
+
+An element of this list can be a cons cell instead of just a
+string. In that case the car must be a string specifying the
+buffer name. This is for compatibility with
+`special-display-buffer-names'; the cdr of the cons cell is
+ignored.
+
+See also `same-window-regexps'."
+ :type '(repeat (string :format "%v"))
+ :group 'windows)
+
+(defcustom same-window-regexps nil
+ "List of regexps saying which buffers should appear in the \"same\" window.
+`display-buffer' and `pop-to-buffer' show a buffer whose name
+matches a regexp on this list in the selected rather than some
+other window.
+
+An element of this list can be a cons cell instead of just a
+string. In that case the car must be a string, which specifies
+the buffer name. This is for compatibility with
+`special-display-buffer-names'; the cdr of the cons cell is
+ignored.
+
+See also `same-window-buffer-names'."
+ :type '(repeat (regexp :format "%v"))
+ :group 'windows)
+
+(defcustom pop-up-frames nil
+ "Whether `display-buffer' should make a separate frame.
+If nil, never make a seperate frame.
+If the value is `graphic-only', make a separate frame
+on graphic displays only.
+Any other non-nil value means always make a separate frame."
+ :type '(choice
+ (const :tag "Never" nil)
+ (const :tag "On graphic displays only" graphic-only)
+ (const :tag "Always" t))
+ :group 'windows)
+
+(defcustom display-buffer-reuse-frames nil
+ "Non-nil means `display-buffer' should reuse frames.
+If the buffer in question is already displayed in a frame, raise
+that frame."
+ :type 'boolean
+ :version "21.1"
+ :group 'windows)
+
+(defcustom pop-up-windows t
+ "Non-nil means `display-buffer' should make a new window."
+ :type 'boolean
+ :group 'windows)
+
+(defcustom split-height-threshold 80
+ "Minimum height of window to be split vertically.
+If the value is a number, `display-buffer' can split a window
+only if it has at least as many lines. If the value is nil,
+`display-buffer' cannot split a window vertically.
+
+If the window is the only window on its frame, `display-buffer'
+can split it regardless of this value."
+ :type '(choice (const nil) (number :tag "lines"))
+ :version "23.1"
+ :group 'windows)
+
+(defcustom split-width-threshold 160
+ "Minimum width of window to be split horizontally.
+If the value is a number, `display-buffer' can split a window
+only if it has at least as many columns. If the value is nil,
+`display-buffer' cannot split a window horizontally."
+ :type '(choice (const nil) (number :tag "columns"))
+ :version "23.1"
+ :group 'windows)
+
+(defcustom split-window-preferred-function nil
+ "Function used by `display-buffer' to split windows.
+If non-nil, a function called with a window as single argument
+supposed to split that window and return the new window. If the
+function returns nil the window is not split.
+
+If nil, `display-buffer' will split the window respecting the
+values of `split-height-threshold' and `split-width-threshold'."
+ :type '(choice (const nil) (function :tag "Function"))
+ :version "23.1"
+ :group 'windows)
+
+(defun window--splittable-p (window &optional horizontal)
+ "Return non-nil if WINDOW can be split evenly.
+Optional argument HORIZONTAL non-nil means check whether WINDOW
+can be split horizontally.
+
+WINDOW can be split vertically when the following conditions
+hold:
+
+- `window-size-fixed' is either nil or equals `width' for the
+ buffer of WINDOW.
+
+- `split-height-threshold' is a number and WINDOW is at least as
+ high as `split-height-threshold'.
+
+- When WINDOW is split evenly, the emanating windows are at least
+ `window-min-height' lines tall and can accommodate at least one
+ line plus - if WINDOW has one - a mode line.
+
+WINDOW can be split horizontally when the following conditions
+hold:
+
+- `window-size-fixed' is either nil or equals `height' for the
+ buffer of WINDOW.
+
+- `split-width-threshold' is a number and WINDOW is at least as
+ wide as `split-width-threshold'.
+
+- When WINDOW is split evenly, the emanating windows are at least
+ `window-min-width' or two (whichever is larger) columns wide."
+ (when (window-live-p window)
+ (with-current-buffer (window-buffer window)
+ (if horizontal
+ ;; A window can be split horizontally when its width is not
+ ;; fixed, it is at least `split-width-threshold' columns wide
+ ;; and at least twice as wide as `window-min-width' and 2 (the
+ ;; latter value is hardcoded).
+ (and (memq window-size-fixed '(nil height))
+ ;; Testing `window-full-width-p' here hardly makes any
+ ;; sense nowadays. This can be done more intuitively by
+ ;; setting up `split-width-threshold' appropriately.
+ (numberp split-width-threshold)
+ (>= (window-width window)
+ (max split-width-threshold
+ (* 2 (max window-min-width 2)))))
+ ;; A window can be split vertically when its height is not
+ ;; fixed, it is at least `split-height-threshold' lines high,
+ ;; and it is at least twice as high as `window-min-height' and 2
+ ;; if it has a modeline or 1.
+ (and (memq window-size-fixed '(nil width))
+ (numberp split-height-threshold)
+ (>= (window-height window)
+ (max split-height-threshold
+ (* 2 (max window-min-height
+ (if mode-line-format 2 1))))))))))
+
+(defun window--try-to-split-window (window)
+ "Split WINDOW if it is splittable.
+See `window--splittable-p' for how to determine whether a window
+is splittable. If WINDOW can be split, return the value returned
+by `split-window' (or `split-window-preferred-function')."
+ (when (and (window-live-p window)
+ (not (frame-parameter (window-frame window) 'unsplittable)))
+ (if (functionp split-window-preferred-function)
+ ;; `split-window-preferred-function' is specified, so use it.
+ (funcall split-window-preferred-function window)
+ (or (and (window--splittable-p window)
+ ;; Split window vertically.
+ (split-window window))
+ (and (window--splittable-p window t)
+ ;; Split window horizontally.
+ (split-window window nil t))
+ (and (eq window (frame-root-window (window-frame window)))
+ (not (window-minibuffer-p window))
+ ;; If WINDOW is the only window on its frame and not the
+ ;; minibuffer window, attempt to split it vertically
+ ;; disregarding the value of `split-height-threshold'.
+ (let ((split-height-threshold 0))
+ (and (window--splittable-p window)
+ (split-window window))))))))
+
+(defun window--frame-usable-p (frame)
+ "Return FRAME if it can be used to display a buffer."
+ (when (frame-live-p frame)
+ (let ((window (frame-root-window frame)))
+ ;; `frame-root-window' may be an internal window which is considered
+ ;; "dead" by `window-live-p'. Hence if `window' is not live we
+ ;; implicitly know that `frame' has a visible window we can use.
+ (when (or (not (window-live-p window))
+ (and (not (window-minibuffer-p window))
+ (not (window-dedicated-p window))))
+ frame))))
+
+(defcustom even-window-heights t
+ "If non-nil `display-buffer' will try to even window heights.
+Otherwise `display-buffer' will leave the window configuration
+alone. Heights are evened only when `display-buffer' chooses a
+window that appears above or below the selected window."
+ :type 'boolean
+ :group 'windows)
+
+(defun window--even-window-heights (window)
+ "Even heights of WINDOW and selected window.
+Do this only if these windows are vertically adjacent to each
+other, `even-window-heights' is non-nil, and the selected window
+is higher than WINDOW."
+ (when (and even-window-heights
+ (not (eq window (selected-window)))
+ ;; Don't resize minibuffer windows.
+ (not (window-minibuffer-p (selected-window)))
+ (> (window-height (selected-window)) (window-height window))
+ (eq (window-frame window) (window-frame (selected-window)))
+ (let ((sel-edges (window-edges (selected-window)))
+ (win-edges (window-edges window)))
+ (and (= (nth 0 sel-edges) (nth 0 win-edges))
+ (= (nth 2 sel-edges) (nth 2 win-edges))
+ (or (= (nth 1 sel-edges) (nth 3 win-edges))
+ (= (nth 3 sel-edges) (nth 1 win-edges))))))
+ (let ((window-min-height 1))
+ ;; Don't throw an error if we can't even window heights for
+ ;; whatever reason.
+ (condition-case nil
+ (enlarge-window (/ (- (window-height window) (window-height)) 2))
+ (error nil)))))
+
+(defun window--display-buffer-1 (window)
+ "Raise the frame containing WINDOW.
+Do not raise the selected frame. Return WINDOW."
+ (let* ((frame (window-frame window))
+ (visible (frame-visible-p frame)))
+ (unless (or (not visible)
+ ;; Assume the selected frame is already visible enough.
+ (eq frame (selected-frame))
+ ;; Assume the frame from which we invoked the minibuffer
+ ;; is visible.
+ (and (minibuffer-window-active-p (selected-window))
+ (eq frame (window-frame (minibuffer-selected-window)))))
+ (raise-frame frame))
+ window))
+
+(defun window--display-buffer-2 (buffer window)
+ "Display BUFFER in WINDOW and make its frame visible.
+Return WINDOW."
+ (when (and (buffer-live-p buffer) (window-live-p window))
+ (set-window-buffer window buffer)
+ (window--display-buffer-1 window)))
+
+(defun display-buffer (buffer-or-name &optional not-this-window frame)
+ "Make buffer BUFFER-OR-NAME appear in some window but don't select it.
+BUFFER-OR-NAME must be a buffer or the name of an existing
+buffer. Return the window chosen to display BUFFER-OR-NAME or
+nil if no such window is found.
+
+Optional argument NOT-THIS-WINDOW non-nil means display the
+buffer in a window other than the selected one, even if it is
+already displayed in the selected window.
+
+Optional argument FRAME specifies which frames to investigate
+when the specified buffer is already displayed. If the buffer is
+already displayed in some window on one of these frames simply
+return that window. Possible values of FRAME are:
+
+`visible' - consider windows on all visible frames.
+
+0 - consider windows on all visible or iconified frames.
+
+t - consider windows on all frames.
+
+A specific frame - consider windows on that frame only.
+
+nil - consider windows on the selected frame \(actually the
+last non-minibuffer frame\) only. If, however, either
+`display-buffer-reuse-frames' or `pop-up-frames' is non-nil
+\(non-nil and not graphic-only on a text-only terminal),
+consider all visible or iconified frames."
+ (interactive "BDisplay buffer:\nP")
+ (let* ((can-use-selected-window
+ ;; The selected window is usable unless either NOT-THIS-WINDOW
+ ;; is non-nil, it is dedicated to its buffer, or it is the
+ ;; `minibuffer-window'.
+ (not (or not-this-window
+ (window-dedicated-p (selected-window))
+ (window-minibuffer-p))))
+ (buffer (if (bufferp buffer-or-name)
+ buffer-or-name
+ (get-buffer buffer-or-name)))
+ (name-of-buffer (buffer-name buffer))
+ ;; On text-only terminals do not pop up a new frame when
+ ;; `pop-up-frames' equals graphic-only.
+ (use-pop-up-frames (if (eq pop-up-frames 'graphic-only)
+ (display-graphic-p)
+ pop-up-frames))
+ ;; `frame-to-use' is the frame where to show `buffer' - either
+ ;; the selected frame or the last nonminibuffer frame.
+ (frame-to-use
+ (or (window--frame-usable-p (selected-frame))
+ (window--frame-usable-p (last-nonminibuffer-frame))))
+ ;; `window-to-use' is the window we use for showing `buffer'.
+ window-to-use)
+ (cond
+ ((not (buffer-live-p buffer))
+ (error "No such buffer %s" buffer))
+ (display-buffer-function
+ ;; Let `display-buffer-function' do the job.
+ (funcall display-buffer-function buffer not-this-window))
+ ((and (not not-this-window)
+ (eq (window-buffer (selected-window)) buffer))
+ ;; The selected window already displays BUFFER and
+ ;; `not-this-window' is nil, so use it.
+ (window--display-buffer-1 (selected-window)))
+ ((and can-use-selected-window (same-window-p name-of-buffer))
+ ;; If the buffer's name tells us to use the selected window do so.
+ (window--display-buffer-2 buffer (selected-window)))
+ ((let ((frames (or frame
+ (and (or use-pop-up-frames
+ display-buffer-reuse-frames
+ (not (last-nonminibuffer-frame)))
+ 0)
+ (last-nonminibuffer-frame))))
+ (and (setq window-to-use (get-buffer-window buffer frames))
+ (or can-use-selected-window
+ (not (eq (selected-window) window-to-use)))))
+ ;; If the buffer is already displayed in some window use that.
+ (window--display-buffer-1 window-to-use))
+ ((and special-display-function
+ ;; `special-display-p' returns either t or a list of frame
+ ;; parameters to pass to `special-display-function'.
+ (let ((pars (special-display-p name-of-buffer)))
+ (when pars
+ (funcall special-display-function
+ buffer (if (listp pars) pars))))))
+ ((or use-pop-up-frames (not frame-to-use))
+ ;; We want or need a new frame.
+ (window--display-buffer-2
+ buffer (frame-selected-window (funcall pop-up-frame-function))))
+ ((and pop-up-windows
+ ;; Make a new window.
+ (or (not (frame-parameter frame-to-use 'unsplittable))
+ ;; If the selected frame cannot be split look at
+ ;; `last-nonminibuffer-frame'.
+ (and (eq frame-to-use (selected-frame))
+ (setq frame-to-use (last-nonminibuffer-frame))
+ (window--frame-usable-p frame-to-use)
+ (not (frame-parameter frame-to-use 'unsplittable))))
+ ;; Attempt to split largest or least recently used window.
+ (setq window-to-use
+ (or (window--try-to-split-window
+ (get-largest-window frame-to-use t))
+ (window--try-to-split-window
+ (get-lru-window frame-to-use t))))
+ (window--display-buffer-2 buffer window-to-use)))
+ ((setq window-to-use
+ ;; Reuse an existing window.
+ (or (get-lru-window frame-to-use)
+ (get-buffer-window buffer 'visible)
+ (get-largest-window 'visible nil)
+ (get-buffer-window buffer 0)
+ (get-largest-window 0 nil)
+ (frame-selected-window (funcall pop-up-frame-function))))
+ (window--even-window-heights window-to-use)
+ (window--display-buffer-2 buffer window-to-use)))))
+
+(defun pop-to-buffer (buffer-or-name &optional other-window norecord)
+ "Select buffer BUFFER-OR-NAME in some window, preferably a different one.
+BUFFER-OR-NAME may be a buffer, a string \(a buffer name), or
+nil. If BUFFER-OR-NAME is a string not naming an existent
+buffer, create a buffer with that name. If BUFFER-OR-NAME is
+nil, choose some other buffer.
+
+If `pop-up-windows' is non-nil, windows can be split to display
+the buffer. If optional second arg OTHER-WINDOW is non-nil,
+insist on finding another window even if the specified buffer is
+already visible in the selected window, and ignore
+`same-window-regexps' and `same-window-buffer-names'.
+
+If the window to show BUFFER-OR-NAME is not on the selected
+frame, raise that window's frame and give it input focus.
+
+This function returns the buffer it switched to. This uses the
+function `display-buffer' as a subroutine; see the documentation
+of `display-buffer' for additional customization information.
+
+Optional third arg NORECORD non-nil means do not put this buffer
+at the front of the list of recently selected ones."
+ (let ((buffer
+ ;; FIXME: This behavior is carried over from the previous C version
+ ;; of pop-to-buffer, but really we should use just
+ ;; `get-buffer' here.
+ (if (null buffer-or-name) (other-buffer (current-buffer))
+ (or (get-buffer buffer-or-name)
+ (let ((buf (get-buffer-create buffer-or-name)))
+ (set-buffer-major-mode buf)
+ buf))))
+ (old-window (selected-window))
+ (old-frame (selected-frame))
+ new-window new-frame)
+ (set-buffer buffer)
+ (setq new-window (display-buffer buffer other-window))
+ (unless (eq new-window old-window)
+ ;; `display-buffer' has chosen another window, select it.
+ (select-window new-window norecord)
+ (setq new-frame (window-frame new-window))
+ (unless (eq new-frame old-frame)
+ ;; `display-buffer' has chosen another frame, make sure it gets
+ ;; input focus and is risen.
+ (select-frame-set-input-focus new-frame)))
+ buffer))
+
+;; I think this should be the default; I think people will prefer it--rms.
+(defcustom split-window-keep-point t
+ "If non-nil, \\[split-window-vertically] keeps the original point \
+in both children.
+This is often more convenient for editing.
+If nil, adjust point in each of the two windows to minimize redisplay.
+This is convenient on slow terminals, but point can move strangely.
+
+This option applies only to `split-window-vertically' and
+functions that call it. `split-window' always keeps the original
+point in both children."
+ :type 'boolean
+ :group 'windows)
+
+(defun split-window-vertically (&optional size)
+ "Split selected window into two windows, one above the other.
+The upper window gets SIZE lines and the lower one gets the rest.
+SIZE negative means the lower window gets -SIZE lines and the
+upper one the rest. With no argument, split windows equally or
+close to it. Both windows display the same buffer, now current.
+
+If the variable `split-window-keep-point' is non-nil, both new
+windows will get the same value of point as the selected window.
+This is often more convenient for editing. The upper window is
+the selected window.
+
+Otherwise, we choose window starts so as to minimize the amount of
+redisplay; this is convenient on slow terminals. The new selected
+window is the one that the current value of point appears in. The
+value of point can change if the text around point is hidden by the
+new mode line.
+
+Regardless of the value of `split-window-keep-point', the upper
+window is the original one and the return value is the new, lower
+window."
+ (interactive "P")
+ (let ((old-window (selected-window))
+ (old-point (point))
+ (size (and size (prefix-numeric-value size)))
+ moved-by-window-height moved new-window bottom)
+ (and size (< size 0)
+ ;; Handle negative SIZE value.
+ (setq size (+ (window-height) size)))
+ (setq new-window (split-window nil size))
+ (unless split-window-keep-point
+ (save-excursion
+ (set-buffer (window-buffer))
+ (goto-char (window-start))
+ (setq moved (vertical-motion (window-height)))
+ (set-window-start new-window (point))
+ (when (> (point) (window-point new-window))
+ (set-window-point new-window (point)))
+ (when (= moved (window-height))
+ (setq moved-by-window-height t)
+ (vertical-motion -1))
+ (setq bottom (point)))
+ (and moved-by-window-height
+ (<= bottom (point))
+ (set-window-point old-window (1- bottom)))
+ (and moved-by-window-height
+ (<= (window-start new-window) old-point)
+ (set-window-point new-window old-point)
+ (select-window new-window)))
+ (split-window-save-restore-data new-window old-window)))
+
+;; This is to avoid compiler warnings.
+(defvar view-return-to-alist)
+
+(defun split-window-save-restore-data (new-window old-window)
+ (with-current-buffer (window-buffer)
+ (when view-mode
+ (let ((old-info (assq old-window view-return-to-alist)))
+ (when old-info
+ (push (cons new-window (cons (car (cdr old-info)) t))
+ view-return-to-alist))))
+ new-window))
+
+(defun split-window-horizontally (&optional size)
+ "Split selected window into two windows side by side.
+The selected window becomes the left one and gets SIZE columns.
+SIZE negative means the right window gets -SIZE lines.
+
+SIZE includes the width of the window's scroll bar; if there are
+no scroll bars, it includes the width of the divider column to
+the window's right, if any. SIZE omitted or nil means split
+window equally.
+
+The selected window remains selected. Return the new window."
+ (interactive "P")
+ (let ((old-window (selected-window))
+ (size (and size (prefix-numeric-value size))))
+ (and size (< size 0)
+ ;; Handle negative SIZE value.
+ (setq size (+ (window-width) size)))
+ (split-window-save-restore-data (split-window nil size t) old-window)))
+
+\f
+(defun set-window-text-height (window height)
+ "Sets the height in lines of the text display area of WINDOW to HEIGHT.
+HEIGHT doesn't include the mode line or header line, if any, or
+any partial-height lines in the text display area.
+
+Note that the current implementation of this function cannot
+always set the height exactly, but attempts to be conservative,
+by allocating more lines than are actually needed in the case
+where some error may be present."
+ (let ((delta (- height (window-text-height window))))
+ (unless (zerop delta)
+ ;; Setting window-min-height to a value like 1 can lead to very
+ ;; bizarre displays because it also allows Emacs to make *other*
+ ;; windows 1-line tall, which means that there's no more space for
+ ;; the modeline.
+ (let ((window-min-height (min 2 height))) ; One text line plus a modeline.
+ (if (and window (not (eq window (selected-window))))
+ (save-selected-window
+ (select-window window 'norecord)
+ (enlarge-window delta))
+ (enlarge-window delta))))))
+
+\f
+(defun enlarge-window-horizontally (columns)
+ "Make selected window COLUMNS wider.
+Interactively, if no argument is given, make selected window one
+column wider."
+ (interactive "p")
+ (enlarge-window columns t))
+
+(defun shrink-window-horizontally (columns)
+ "Make selected window COLUMNS narrower.
+Interactively, if no argument is given, make selected window one
+column narrower."
+ (interactive "p")
+ (shrink-window columns t))
+
+(defun window-buffer-height (window)
+ "Return the height (in screen lines) of the buffer that WINDOW is displaying."
+ (with-current-buffer (window-buffer window)
+ (max 1
+ (count-screen-lines (point-min) (point-max)
+ ;; If buffer ends with a newline, ignore it when
+ ;; counting height unless point is after it.
+ (eobp)
+ window))))
+
+(defun count-screen-lines (&optional beg end count-final-newline window)
+ "Return the number of screen lines in the region.
+The number of screen lines may be different from the number of actual lines,
+due to line breaking, display table, etc.
+
+Optional arguments BEG and END default to `point-min' and `point-max'
+respectively.
+
+If region ends with a newline, ignore it unless optional third argument
+COUNT-FINAL-NEWLINE is non-nil.
+
+The optional fourth argument WINDOW specifies the window used for obtaining
+parameters such as width, horizontal scrolling, and so on. The default is
+to use the selected window's parameters.
+
+Like `vertical-motion', `count-screen-lines' always uses the current buffer,
+regardless of which buffer is displayed in WINDOW. This makes possible to use
+`count-screen-lines' in any buffer, whether or not it is currently displayed
+in some window."
+ (unless beg
+ (setq beg (point-min)))
+ (unless end
+ (setq end (point-max)))
+ (if (= beg end)
+ 0
+ (save-excursion
+ (save-restriction
+ (widen)
+ (narrow-to-region (min beg end)
+ (if (and (not count-final-newline)
+ (= ?\n (char-before (max beg end))))
+ (1- (max beg end))
+ (max beg end)))
+ (goto-char (point-min))
+ (1+ (vertical-motion (buffer-size) window))))))
+
+(defun fit-window-to-buffer (&optional window max-height min-height)
+ "Adjust height of WINDOW to display its buffer's contents exactly.
+WINDOW defaults to the selected window.
+Optional argument MAX-HEIGHT specifies the maximum height of the
+window and defaults to the height of WINDOW's frame.
+Optional argument MIN-HEIGHT specifies the minimum height of the
+window and defaults to `window-min-height'.
+Both, MAX-HEIGHT and MIN-HEIGHT are specified in lines and
+include the mode line and header line, if any.
+Always return nil."
+ (interactive)
+
+ (when (null window)
+ (setq window (selected-window)))
+ (when (null max-height)
+ (setq max-height (frame-height (window-frame window))))
+
+ (let* ((buf
+ ;; Buffer that is displayed in WINDOW
+ (window-buffer window))
+ (window-height
+ ;; The current height of WINDOW
+ (window-height window))
+ (desired-height
+ ;; The height necessary to show the buffer displayed by WINDOW
+ ;; (`count-screen-lines' always works on the current buffer).
+ (with-current-buffer buf
+ (+ (count-screen-lines)
+ ;; If the buffer is empty, (count-screen-lines) is
+ ;; zero. But, even in that case, we need one text line
+ ;; for cursor.
+ (if (= (point-min) (point-max))
+ 1 0)
+ ;; For non-minibuffers, count the mode-line, if any
+ (if (and (not (window-minibuffer-p window))
+ mode-line-format)
+ 1 0)
+ ;; Count the header-line, if any
+ (if header-line-format 1 0))))
+ (delta
+ ;; Calculate how much the window height has to change to show
+ ;; desired-height lines, constrained by MIN-HEIGHT and MAX-HEIGHT.
+ (- (max (min desired-height max-height)
+ (or min-height window-min-height))
+ window-height)))
+
+ ;; Don't try to redisplay with the cursor at the end
+ ;; on its own line--that would force a scroll and spoil things.
+ (when (with-current-buffer buf
+ (and (eobp) (bolp) (not (bobp))))
+ (set-window-point window (1- (window-point window))))
+
+ (save-selected-window
+ (select-window window 'norecord)
+
+ ;; Adjust WINDOW to the nominally correct size (which may actually
+ ;; be slightly off because of variable height text, etc).
+ (unless (zerop delta)
+ (enlarge-window delta))
+
+ ;; Check if the last line is surely fully visible. If not,
+ ;; enlarge the window.
+ (let ((end (with-current-buffer buf
+ (save-excursion
+ (goto-char (point-max))
+ (when (and (bolp) (not (bobp)))
+ ;; Don't include final newline
+ (backward-char 1))
+ (when truncate-lines
+ ;; If line-wrapping is turned off, test the
+ ;; beginning of the last line for visibility
+ ;; instead of the end, as the end of the line
+ ;; could be invisible by virtue of extending past
+ ;; the edge of the window.
+ (forward-line 0))
+ (point)))))
+ (set-window-vscroll window 0)
+ (while (and (< desired-height max-height)
+ (= desired-height (window-height window))
+ (not (pos-visible-in-window-p end window)))
+ (enlarge-window 1)
+ (setq desired-height (1+ desired-height)))))))
+
+(defun window-safely-shrinkable-p (&optional window)
+ "Return t if WINDOW can be shrunk without shrinking other windows.
+WINDOW defaults to the selected window."
+ (with-selected-window (or window (selected-window))
+ (let ((edges (window-edges)))
+ (or (= (nth 2 edges) (nth 2 (window-edges (previous-window))))
+ (= (nth 0 edges) (nth 0 (window-edges (next-window))))))))
+
+(defun shrink-window-if-larger-than-buffer (&optional window)
+ "Shrink height of WINDOW if its buffer doesn't need so many lines.
+More precisely, shrink WINDOW vertically to be as small as
+possible, while still showing the full contents of its buffer.
+WINDOW defaults to the selected window.
+
+Do not shrink to less than `window-min-height' lines. Do nothing
+if the buffer contains more lines than the present window height,
+or if some of the window's contents are scrolled out of view, or
+if shrinking this window would also shrink another window, or if
+the window is the only window of its frame.
+
+Return non-nil if the window was shrunk, nil otherwise."
+ (interactive)
+ (when (null window)
+ (setq window (selected-window)))
+ (let* ((frame (window-frame window))
+ (mini (frame-parameter frame 'minibuffer))
+ (edges (window-edges window)))
+ (if (and (not (eq window (frame-root-window frame)))
+ (window-safely-shrinkable-p window)
+ (pos-visible-in-window-p (point-min) window)
+ (not (eq mini 'only))
+ (or (not mini)
+ (let ((mini-window (minibuffer-window frame)))
+ (or (null mini-window)
+ (not (eq frame (window-frame mini-window)))
+ (< (nth 3 edges)
+ (nth 1 (window-edges mini-window)))
+ (> (nth 1 edges)
+ (frame-parameter frame 'menu-bar-lines))))))
+ (fit-window-to-buffer window (window-height window)))))
+
+(defun kill-buffer-and-window ()
+ "Kill the current buffer and delete the selected window."
+ (interactive)
+ (let ((window-to-delete (selected-window))
+ (buffer-to-kill (current-buffer))
+ (delete-window-hook (lambda ()
+ (condition-case nil
+ (delete-window)
+ (error nil)))))
+ (unwind-protect
+ (progn
+ (add-hook 'kill-buffer-hook delete-window-hook t t)
+ (if (kill-buffer (current-buffer))
+ ;; If `delete-window' failed before, we rerun it to regenerate
+ ;; the error so it can be seen in the echo area.
+ (when (eq (selected-window) window-to-delete)
+ (delete-window))))
+ ;; If the buffer is not dead for some reason (probably because
+ ;; of a `quit' signal), remove the hook again.
+ (condition-case nil
+ (with-current-buffer buffer-to-kill
+ (remove-hook 'kill-buffer-hook delete-window-hook t))
+ (error nil)))))
+
+(defun quit-window (&optional kill window)
+ "Quit WINDOW and bury its buffer.
+With a prefix argument, kill the buffer instead. WINDOW defaults
+to the selected window.
+
+If WINDOW is non-nil, dedicated, or a minibuffer window, delete
+it and, if it's alone on its frame, its frame too. Otherwise, or
+if deleting WINDOW fails in any of the preceding cases, display
+another buffer in WINDOW using `switch-to-buffer'.
+
+Optional argument KILL non-nil means kill WINDOW's buffer.
+Otherwise, bury WINDOW's buffer, see `bury-buffer'."
+ (interactive "P")
+ (let ((buffer (window-buffer window)))
+ (if (or window
+ (window-minibuffer-p window)
+ (window-dedicated-p window))
+ ;; WINDOW is either non-nil, a minibuffer window, or dedicated;
+ ;; try to delete it.
+ (let ((frame (window-frame (or window (selected-window)))))
+ (if (eq window (frame-root-window frame))
+ ;; WINDOW is alone on its frame. `delete-windows-on'
+ ;; knows how to handle that case.
+ (delete-windows-on buffer frame)
+ ;; There are other windows on its frame, delete WINDOW.
+ (delete-window window)))
+ ;; Otherwise, switch to another buffer in the selected window.
+ (switch-to-buffer nil))
+
+ ;; Deal with the buffer.
+ (if kill
+ (kill-buffer buffer)
+ (bury-buffer buffer))))
+
+(defvar recenter-last-op nil
+ "Indicates the last recenter operation performed.
+Possible values: `top', `middle', `bottom'.")
+
+(defun recenter-top-bottom (&optional arg)
+ "Move current line to window center, top, and bottom, successively.
+With no prefix argument, the first call redraws the frame and
+ centers point vertically within the window. Successive calls
+ scroll the window, placing point on the top, bottom, and middle
+ consecutively. The cycling order is middle -> top -> bottom.
+
+A prefix argument is handled like `recenter':
+ With numeric prefix ARG, move current line to window-line ARG.
+ With plain `C-u', move current line to window center.
+
+Top and bottom destinations are actually `scroll-margin' lines
+ the from true window top and bottom."
+ (interactive "P")
+ (cond
+ (arg (recenter arg)) ; Always respect ARG.
+ ((or (not (eq this-command last-command))
+ (eq recenter-last-op 'bottom))
+ (setq recenter-last-op 'middle)
+ (recenter))
+ (t
+ (let ((this-scroll-margin
+ (min (max 0 scroll-margin)
+ (truncate (/ (window-body-height) 4.0)))))
+ (cond ((eq recenter-last-op 'middle)
+ (setq recenter-last-op 'top)
+ (recenter this-scroll-margin))
+ ((eq recenter-last-op 'top)
+ (setq recenter-last-op 'bottom)
+ (recenter (- -1 this-scroll-margin))))))))
+
+(define-key global-map [?\C-l] 'recenter-top-bottom)
+\f
+(defvar mouse-autoselect-window-timer nil
+ "Timer used by delayed window autoselection.")
+
+(defvar mouse-autoselect-window-position nil
+ "Last mouse position recorded by delayed window autoselection.")
+
+(defvar mouse-autoselect-window-window nil
+ "Last window recorded by delayed window autoselection.")
+
+(defvar mouse-autoselect-window-state nil
+ "When non-nil, special state of delayed window autoselection.
+Possible values are `suspend' \(suspend autoselection after a menu or
+scrollbar interaction\) and `select' \(the next invocation of
+'handle-select-window' shall select the window immediately\).")
+
+(defun mouse-autoselect-window-cancel (&optional force)
+ "Cancel delayed window autoselection.
+Optional argument FORCE means cancel unconditionally."
+ (unless (and (not force)
+ ;; Don't cancel for select-window or select-frame events
+ ;; or when the user drags a scroll bar.
+ (or (memq this-command
+ '(handle-select-window handle-switch-frame))
+ (and (eq this-command 'scroll-bar-toolkit-scroll)
+ (memq (nth 4 (event-end last-input-event))
+ '(handle end-scroll)))))
+ (setq mouse-autoselect-window-state nil)
+ (when (timerp mouse-autoselect-window-timer)
+ (cancel-timer mouse-autoselect-window-timer))
+ (remove-hook 'pre-command-hook 'mouse-autoselect-window-cancel)))
+
+(defun mouse-autoselect-window-start (mouse-position &optional window suspend)
+ "Start delayed window autoselection.
+MOUSE-POSITION is the last position where the mouse was seen as returned
+by `mouse-position'. Optional argument WINDOW non-nil denotes the
+window where the mouse was seen. Optional argument SUSPEND non-nil
+means suspend autoselection."
+ ;; Record values for MOUSE-POSITION, WINDOW, and SUSPEND.
+ (setq mouse-autoselect-window-position mouse-position)
+ (when window (setq mouse-autoselect-window-window window))
+ (setq mouse-autoselect-window-state (when suspend 'suspend))
+ ;; Install timer which runs `mouse-autoselect-window-select' after
+ ;; `mouse-autoselect-window' seconds.
+ (setq mouse-autoselect-window-timer
+ (run-at-time
+ (abs mouse-autoselect-window) nil 'mouse-autoselect-window-select)))
+
+(defun mouse-autoselect-window-select ()
+ "Select window with delayed window autoselection.
+If the mouse position has stabilized in a non-selected window, select
+that window. The minibuffer window is selected only if the minibuffer is
+active. This function is run by `mouse-autoselect-window-timer'."
+ (condition-case nil
+ (let* ((mouse-position (mouse-position))
+ (window
+ (condition-case nil
+ (window-at (cadr mouse-position) (cddr mouse-position)
+ (car mouse-position))
+ (error nil))))
+ (cond
+ ((or (menu-or-popup-active-p)
+ (and window
+ (not (coordinates-in-window-p (cdr mouse-position) window))))
+ ;; A menu / popup dialog is active or the mouse is on the scroll-bar
+ ;; of WINDOW, temporarily suspend delayed autoselection.
+ (mouse-autoselect-window-start mouse-position nil t))
+ ((eq mouse-autoselect-window-state 'suspend)
+ ;; Delayed autoselection was temporarily suspended, reenable it.
+ (mouse-autoselect-window-start mouse-position))
+ ((and window (not (eq window (selected-window)))
+ (or (not (numberp mouse-autoselect-window))
+ (and (> mouse-autoselect-window 0)
+ ;; If `mouse-autoselect-window' is positive, select
+ ;; window if the window is the same as before.
+ (eq window mouse-autoselect-window-window))
+ ;; Otherwise select window if the mouse is at the same
+ ;; position as before. Observe that the first test after
+ ;; starting autoselection usually fails since the value of
+ ;; `mouse-autoselect-window-position' recorded there is the
+ ;; position where the mouse has entered the new window and
+ ;; not necessarily where the mouse has stopped moving.
+ (equal mouse-position mouse-autoselect-window-position))
+ ;; The minibuffer is a candidate window if it's active.
+ (or (not (window-minibuffer-p window))
+ (eq window (active-minibuffer-window))))
+ ;; Mouse position has stabilized in non-selected window: Cancel
+ ;; delayed autoselection and try to select that window.
+ (mouse-autoselect-window-cancel t)
+ ;; Select window where mouse appears unless the selected window is the
+ ;; minibuffer. Use `unread-command-events' in order to execute pre-
+ ;; and post-command hooks and trigger idle timers. To avoid delaying
+ ;; autoselection again, set `mouse-autoselect-window-state'."
+ (unless (window-minibuffer-p (selected-window))
+ (setq mouse-autoselect-window-state 'select)
+ (setq unread-command-events
+ (cons (list 'select-window (list window))
+ unread-command-events))))
+ ((or (and window (eq window (selected-window)))
+ (not (numberp mouse-autoselect-window))
+ (equal mouse-position mouse-autoselect-window-position))
+ ;; Mouse position has either stabilized in the selected window or at
+ ;; `mouse-autoselect-window-position': Cancel delayed autoselection.
+ (mouse-autoselect-window-cancel t))
+ (t
+ ;; Mouse position has not stabilized yet, resume delayed
+ ;; autoselection.
+ (mouse-autoselect-window-start mouse-position window))))
+ (error nil)))
+
+(defun handle-select-window (event)
+ "Handle select-window events."
+ (interactive "e")
+ (let ((window (posn-window (event-start event))))
+ (unless (or (not (window-live-p window))
+ ;; Don't switch if we're currently in the minibuffer.
+ ;; This tries to work around problems where the
+ ;; minibuffer gets unselected unexpectedly, and where
+ ;; you then have to move your mouse all the way down to
+ ;; the minibuffer to select it.
+ (window-minibuffer-p (selected-window))
+ ;; Don't switch to minibuffer window unless it's active.
+ (and (window-minibuffer-p window)
+ (not (minibuffer-window-active-p window)))
+ ;; Don't switch when autoselection shall be delayed.
+ (and (numberp mouse-autoselect-window)
+ (not (zerop mouse-autoselect-window))
+ (not (eq mouse-autoselect-window-state 'select))
+ (progn
+ ;; Cancel any delayed autoselection.
+ (mouse-autoselect-window-cancel t)
+ ;; Start delayed autoselection from current mouse
+ ;; position and window.
+ (mouse-autoselect-window-start (mouse-position) window)
+ ;; Executing a command cancels delayed autoselection.
+ (add-hook
+ 'pre-command-hook 'mouse-autoselect-window-cancel))))
+ (when mouse-autoselect-window
+ ;; Reset state of delayed autoselection.
+ (setq mouse-autoselect-window-state nil)
+ ;; Run `mouse-leave-buffer-hook' when autoselecting window.
+ (run-hooks 'mouse-leave-buffer-hook))
+ (select-window window))))
+
+(defun delete-other-windows-vertically (&optional window)
+ "Delete the windows in the same column with WINDOW, but not WINDOW itself.
+This may be a useful alternative binding for \\[delete-other-windows]
+ if you often split windows horizontally."
+ (interactive)
+ (let* ((window (or window (selected-window)))
+ (edges (window-edges window))
+ (w window) delenda)
+ (while (not (eq (setq w (next-window w 1)) window))
+ (let ((e (window-edges w)))
+ (when (and (= (car e) (car edges))
+ (= (caddr e) (caddr edges)))
+ (push w delenda))))
+ (mapc 'delete-window delenda)))
+
+(defun truncated-partial-width-window-p (&optional window)
+ "Return non-nil if lines in WINDOW are specifically truncated due to its width.
+WINDOW defaults to the selected window.
+Return nil if WINDOW is not a partial-width window
+ (regardless of the value of `truncate-lines').
+Otherwise, consult the value of `truncate-partial-width-windows'
+ for the buffer shown in WINDOW."
+ (unless window
+ (setq window (selected-window)))
+ (unless (window-full-width-p window)
+ (let ((t-p-w-w (buffer-local-value 'truncate-partial-width-windows
+ (window-buffer window))))
+ (if (integerp t-p-w-w)
+ (< (window-width window) t-p-w-w)
+ t-p-w-w))))
+
+(define-key ctl-x-map "2" 'split-window-vertically)
+(define-key ctl-x-map "3" 'split-window-horizontally)
+(define-key ctl-x-map "}" 'enlarge-window-horizontally)
+(define-key ctl-x-map "{" 'shrink-window-horizontally)
+(define-key ctl-x-map "-" 'shrink-window-if-larger-than-buffer)
+(define-key ctl-x-map "+" 'balance-windows)
+(define-key ctl-x-4-map "0" 'kill-buffer-and-window)
+
+;; arch-tag: b508dfcc-c353-4c37-89fa-e773fe10cea9
+;;; window.el ends here
projects / emacs.git / commitdiff