anchor.diff:    (%%%=-aref value hash (%href-key hash key)))
   
   (defun %href-==? (x)
  -  (in? x #'== #'string== #'number==))
  +  (| (eq x #'==)
  +     (eq x #'string==)
  +     (eq x #'number==)))
   
   (defun =-href (value hash key)
     (!? (%htest hash)
  
positive.code:   (when (| a b)
      (| a (= a (make-hash-table :test b.__tre-test)))
      (? (defined? b.__tre-keys)
         (= a.__tre-keys (*Object.create b.__tre-keys)))
      (%= nil (%%native
                  "for (var k in " b ") "
                      "if (k != \"" '__tre-object-id "\" && k != \"" '__tre-test "\" && k != \"" '__tre-keys "\") "
  
negative.code:       (%%%=-aref value hash key)))
  
  (defun %href-user (hash key)
    (@ (k (hashkeys hash))
      (& (funcall hash.__tre-test k key)
         (return (%%%aref hash (%href-key hash k))))))
  
  (defun href (hash key)
    (!? (%htest hash)
  