+(define-setf-expander aref (array index)
+ (let ((g!array (gensym))
+ (g!index (gensym))
+ (g!value (gensym)))
+ (values (list g!array g!index)
+ (list array index)
+ (list g!value)
+ `(aset ,g!array ,g!index ,g!value)
+ `(aref ,g!array ,g!index))))
+