2005-12-16 Lőrentey Károly <lorentey@elte.hu>

	* bindings.el (last-buffer): Move to simple.el.
	* simple.el (last-buffer): Move here.
	(get-next-valid-buffer): New function.
	(next-buffer): Use frame-local buffer list, maintain buried buffer list.
	(prev-buffer): Ditto. Rename to `previous-buffer'.

	* menu-bar.el (menu-bar-update-buffers): Update references to `prev-buffer'.
	* bindings.el (global-map): Ditto.

4 files changed, 72 insertions, 41 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 9c4bb748bc3..f967252d5c0 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,14 @@
+2005-12-16  L$,1 q(Brentey K,Aa(Broly  <lorentey@elte.hu>
+
+        * bindings.el (last-buffer): Move to simple.el.
+        * simple.el (last-buffer): Move here.
+        (get-next-valid-buffer): New function.
+        (next-buffer): Use frame-local buffer list, maintain buried buffer list.
+        (prev-buffer): Ditto. Rename to `previous-buffer'.
+
+        * menu-bar.el (menu-bar-update-buffers): Update references to `prev-buffer'.
+        * bindings.el (global-map): Ditto.
+
 2005-12-15  Luc Teirlinck  <teirllm@auburn.edu>
 
         * cus-edit.el: Introductory comment change.
diff --git a/lisp/bindings.el b/lisp/bindings.el
index dbab5f00f0b..7e9467b19c5 100644
--- a/lisp/bindings.el
+++ b/lisp/bindings.el
@@ -338,29 +338,6 @@ Keymap to display on minor modes.")
 (defvar mode-line-buffer-identification-keymap nil "\
 Keymap for what is displayed by `mode-line-buffer-identification'.")
 
-(defun last-buffer () "\
-Return the last non-hidden buffer in the buffer list."
-  ;; This logic is more or less copied from bury-buffer,
-  ;; except that we reverse the buffer list.
-  (let ((list (nreverse (buffer-list (selected-frame))))
-        (pred (frame-parameter nil 'buffer-predicate))
-        found notsogood)
-    (while (and list (not found))
-      (unless (or (eq (aref (buffer-name (car list)) 0) ? )
-                  ;; If the selected frame has a buffer_predicate,
-                  ;; disregard buffers that don't fit the predicate.
-                  (and pred (not (funcall pred (car list)))))
-        (if (get-buffer-window (car list) 'visible)
-            (or notsogood (eq (car list) (current-buffer)))
-          (setq found (car list))))
-      (pop list))
-    (or found notsogood
-        (get-buffer "*scratch*")
-        (progn
-          (set-buffer-major-mode
-           (get-buffer-create "*scratch*"))
-          (get-buffer "*scratch*")))))
-
 (defun unbury-buffer () "\
 Switch to the last buffer in the buffer list."
   (interactive)
@@ -673,8 +650,8 @@ language you are using."
 
 (define-key global-map [?\C-x right] 'next-buffer)
 (define-key global-map [?\C-x C-right] 'next-buffer)
-(define-key global-map [?\C-x left] 'prev-buffer)
-(define-key global-map [?\C-x C-left] 'prev-buffer)
+(define-key global-map [?\C-x left] 'previous-buffer)
+(define-key global-map [?\C-x C-left] 'previous-buffer)
 
 (let ((map minibuffer-local-map))
   (define-key map "\en"   'next-history-element)
diff --git a/lisp/menu-bar.el b/lisp/menu-bar.el
index 3d226b9258b..9edd38db86d 100644
--- a/lisp/menu-bar.el
+++ b/lisp/menu-bar.el
@@ -1662,10 +1662,10 @@ Buffers menu is regenerated."
                              "Next Buffer"
                              'next-buffer
                              :help "Switch to the \"next\" buffer in a cyclic order")
-                       (list 'prev-buffer
+                       (list 'previous-buffer
                              'menu-item
                              "Previous Buffer"
-                             'prev-buffer
+                             'previous-buffer
                              :help "Switch to the \"previous\" buffer in a cyclic order")
                        (list 'select-named-buffer
                              'menu-item
diff --git a/lisp/simple.el b/lisp/simple.el
index 93f6329a255..ec123c73cd8 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -52,25 +52,68 @@ wait this many seconds after Emacs becomes idle before doing an update."
   "Highlight (un)matching of parens and expressions."
   :group 'matching)
 
+(defun get-next-valid-buffer (list &optional buffer visible-ok frame) "\
+Search LIST for a valid buffer to display in FRAME.
+Return nil when all buffers in LIST are undesirable for display,
+otherwise return the first suitable buffer in LIST.
+
+Buffers not visible in windows are preferred to visible buffers,
+unless VISIBLE-OK is non-nil.
+If the optional argument FRAME is nil, it defaults to the selected frame.
+If BUFFER is non-nil, ignore occurances of that buffer in LIST."
+  ;; This logic is more or less copied from other-buffer.
+  (setq frame (or frame (selected-frame)))
+  (let ((pred (frame-parameter frame 'buffer-predicate))
+        found buf)
+    (while (and (not found) list)
+      (setq buf (car list))
+      (if (and (not (eq buffer buf))
+               (buffer-live-p buf)
+               (or (null pred) (funcall pred buf))
+               (not (eq (aref (buffer-name buf) 0) ?\s))
+               (or visible-ok (null (get-buffer-window buf 'visible))))
+          (setq found buf)
+        (setq list (cdr list))))
+    (car list)))
+
+(defun last-buffer (&optional buffer visible-ok frame) "\
+Return the last non-hidden displayable buffer in the buffer list.
+If BUFFER is non-nil, last-buffer will ignore that buffer.
+Buffers not visible in windows are preferred to visible buffers,
+unless optional argument VISIBLE-OK is non-nil.
+If the optional third argument FRAME is non-nil, use that frame's
+buffer list instead of the selected frame's buffer list.
+If no other buffer exists, the buffer `*scratch*' is returned."
+  (setq frame (or frame (selected-frame)))
+  (or (get-next-valid-buffer (frame-parameter frame 'buried-buffer-list)
+                             buffer visible-ok frame)
+      (get-next-valid-buffer (nreverse (buffer-list frame))
+                             buffer visible-ok frame)
+      (progn
+        (set-buffer-major-mode (get-buffer-create "*scratch*"))
+        (get-buffer "*scratch*"))))
+
 (defun next-buffer ()
   "Switch to the next buffer in cyclic order."
   (interactive)
-  (let ((buffer (current-buffer)))
-    (switch-to-buffer (other-buffer buffer))
-    (bury-buffer buffer)))
-
-(defun prev-buffer ()
+  (let ((buffer (current-buffer))
+        (bbl (frame-parameter nil 'buried-buffer-list)))
+    (switch-to-buffer (other-buffer buffer t))
+    (bury-buffer buffer)
+    (set-frame-parameter nil 'buried-buffer-list
+                         (cons buffer (delq buffer bbl)))))
+
+(defun previous-buffer ()
   "Switch to the previous buffer in cyclic order."
   (interactive)
-  (let ((list (nreverse (buffer-list)))
-        found)
-    (while (and (not found) list)
-      (let ((buffer (car list)))
-        (if (and (not (get-buffer-window buffer))
-                 (not (string-match "\\` " (buffer-name buffer))))
-            (setq found buffer)))
-      (setq list (cdr list)))
-    (switch-to-buffer found)))
+  (let ((buffer (last-buffer (current-buffer) t))
+        (bbl (frame-parameter nil 'buried-buffer-list)))
+    (switch-to-buffer buffer)
+    ;; Clean up buried-buffer-list up to and including the chosen buffer.
+    (while (and bbl (not (eq (car bbl) buffer)))
+      (setq bbl (cdr bbl)))
+    (set-frame-parameter nil 'buried-buffer-list bbl)))
+
 
 ;;; next-error support framework