-
-(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 occurrences 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 buffer in FRAME's buffer list.
-If BUFFER is the last buffer, return the preceding buffer instead.
-Buffers not visible in windows are preferred to visible buffers,
-unless optional argument VISIBLE-OK is non-nil.
-Optional third argument FRAME nil or omitted means use the
-selected frame's buffer list.
-If no such buffer exists, return the buffer `*scratch*', creating
-it if necessary."
- (setq frame (or frame (selected-frame)))
- (or (get-next-valid-buffer (nreverse (buffer-list frame))
- buffer visible-ok frame)
- (get-buffer "*scratch*")
- (let ((scratch (get-buffer-create "*scratch*")))
- (set-buffer-major-mode scratch)
- scratch)))
-
-(defun next-buffer ()
- "Switch to the next buffer in cyclic order."
- (interactive)
- (let ((buffer (current-buffer)))
- (switch-to-buffer (other-buffer buffer t))
- (bury-buffer buffer)))
-
-(defun previous-buffer ()
- "Switch to the previous buffer in cyclic order."
- (interactive)
- (switch-to-buffer (last-buffer (current-buffer) t)))
-