anchor.diff:      (with-gensyms (ht)
         `(let ((,ht (make-hash-table
                      :test ,test
  -                   :size ,(max hash-table-default-size
  +                   :size ,(max +hash-table-default-size+
                                  (truncate (length keys-and-values)
                                            2)))))
            ,@(unsplice
  
positive.code: (export '(pophash swaphash
            dict dict* @ href href-default
            merge-tables flip-hash-table
            maphash-return
            set-hash-table hash-table-set))
  
  (-> dict (&rest t) hash-table)
  
negative.code: (-> merge-tables (hash-table &rest hash-table)
      hash-table)
  
  (defconstant +hash-table-default-size+
    (hash-table-size (make-hash-table)))
  
  (deftype ok-hash-table-test ()
  