(macrolet ((make-mumble-equal (type)
	     ;; Since caching is only done for objects created by the
	     ;; client, we must always compare ID and display for
	     ;; non-identical mumbles.
	     (let ((predicate (xintern type '-equal))
		   (id (xintern type '-id))
		   (dpy (xintern type '-display)))
		`(within-definition (,type make-mumble-equal)
		   (defun ,predicate (a b)
		     (declare (type (or null ,type) a b))
                     (when (and a b)
                       (or (eql a b)
                           (and (= (,id a) (,id b))
                                (eq (,dpy a) (,dpy b))))))))))
  (make-mumble-equal window)
  (make-mumble-equal pixmap)
  (make-mumble-equal cursor)
  (make-mumble-equal font)
  (make-mumble-equal gcontext)
  (make-mumble-equal colormap)
  (make-mumble-equal drawable))