(one-window-p, walk-windows, minibuffer-window-active-p): Functions moved here.

lisp/window.el

@@ -22,6 +22,70 @@
 
 ;;; Code:
 
+;;;; Window tree functions.
+
+(defun one-window-p (&optional nomini all-frames)
+  "Returns non-nil if the selected window is the only window (in its frame).
+Optional arg NOMINI non-nil means don't count the minibuffer
+even if 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).
+If ALL-FRAMES is neither nil nor t, 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 walk-windows (proc &optional minibuf all-frames)
+  "Cycle through all visible windows, calling PROC for each one.
+PROC is called with a window as argument.
+
+Optional second arg MINIBUF t means count the minibuffer window even
+if not active.  MINIBUF nil or omitted means count the minibuffer iff
+it is active.  MINIBUF neither t nor nil means not to count the
+minibuffer even if it is active.
+
+Several frames may share a single minibuffer; if the minibuffer
+counts, all windows on all frames that share that minibuffer count
+too.  Therefore, when a separate minibuffer frame is active,
+`walk-windows' includes the windows in the frame from which you
+entered the minibuffer, as well as the minibuffer window.  But if the
+minibuffer does not count, only windows from WINDOW's frame count.
+
+Optional third arg ALL-FRAMES t means include windows on all frames.
+ALL-FRAMES nil or omitted means cycle within the frames as specified
+above.  ALL-FRAMES = `visible' means include windows on all visible frames.
+ALL-FRAMES = 0 means include windows on all visible and iconified frames.
+Anything else means restrict to WINDOW's frame."
+  ;; If we start from the minibuffer window, don't fail to come back to it.
+  (if (window-minibuffer-p (selected-window))
+      (setq minibuf t))
+  (let* ((walk-windows-start (selected-window))
+	 (walk-windows-current walk-windows-start))
+    (while (progn
+	     (setq walk-windows-current
+		   (next-window walk-windows-current minibuf all-frames))
+	     (funcall proc walk-windows-current)
+	     (not (eq walk-windows-current walk-windows-start))))))
+
+(defun minibuffer-window-active-p (window)
+  "Return t if WINDOW (a minibuffer window) is now active."
+  ;; nil nil means include WINDOW's frame
+  ;; and other frames using WINDOW as minibuffer,
+  ;; and include minibuffer if active.
+  (let ((prev (previous-window window nil nil)))
+    ;; If PREV equals WINDOW, WINDOW must be on a minibuffer-only frame
+    ;; and it's not currently being used.  So return nil.
+    (and (not (eq window prev))
+	 (let ((should-be-same (next-window prev nil nil)))
+	   ;; If next-window doesn't reverse previous-window,
+	   ;; WINDOW must be outside the cycle specified by nil nil.
+	   (eq should-be-same window)))))
+
 (defun count-windows (&optional minibuf)
    "Returns the number of visible windows.
 Optional arg NO-MINI non-nil means don't count the minibuffer
@@ -73,7 +137,7 @@ even if it is active."
 				(enlarge-window (- newsize
 						   (window-height))))))
 		  'nomini)))
-
+
 ;;; I think this should be the default; I think people will prefer it--rms.
 (defvar split-window-keep-point t
   "*If non-nil, split windows keeps the original point in both children.
@@ -133,7 +197,7 @@ No arg means split equally."
     (and size (< size 0)
 	 (setq size (+ (window-width) size)))
     (split-window nil size t)))
-
+
 (defun enlarge-window-horizontally (arg)
   "Make current window ARG columns wider."
   (interactive "p")