If the optional fourth argument NEW-FRAME is given,
copy the information from face OLD-FACE on frame FRAME
-to NEW-FACE on frame NEW-FRAME."
+to NEW-FACE on frame NEW-FRAME. In this case, FRAME may not be nil."
(let ((inhibit-quit t))
(if (null frame)
(progn
+ (when new-frame
+ (error "Copying face %s from all frames to one frame"
+ old-face))
+ (make-empty-face new-face)
(dolist (frame (frame-list))
(copy-face old-face new-face frame))
(copy-face old-face new-face t))
+ (make-empty-face new-face)
(internal-copy-lisp-face old-face new-face frame new-frame))
new-face))