anchor.diff:                                              bottom)
                                           removed))))
           (values (if removed (make-instance (type-of container)
  -                                           :equal-fn (read-equal-fn container)
                                              :hash-fn (read-hash-fn container)
                                              :root new-root
                                              :equal-fn (read-equal-fn container)
  
positive.code:                                :equal-fn (read-equal-fn container)
                                 :hash-fn (read-hash-fn container)
                                 :root result
                                 :equal-fn (read-equal-fn container)
                                 :max-depth (read-max-depth container))
                  rep
                  old)))))
  
negative.code:                                    :equal-fn (read-equal-fn container)
                                     :hash-fn (read-hash-fn container)
                                     :root result
                                     :max-depth (read-max-depth container)
                                     :size (1+ (access-size container)))
                      container)
  