anchor.diff:                    (t (call-next-method))))))
         (call-next-method)))
   
  -(defmethod display-parse-tree ((parser-symbol literal-object-lexeme) stream (drei drei)
  +(defmethod display-parse-tree ((parser-symbol literal-object-form) stream (drei drei)
                                  (syntax lisp-syntax))
     (updating-output
         (stream :unique-id (list drei parser-symbol)
  
positive.code:   (when read
      (read-from-string (form-string syntax form))))
  
  (defmethod form-to-object ((syntax lisp-syntax) (form literal-object-lexeme) &key &allow-other-keys)
    (object-after (start-mark form)))
  
  (defmethod form-to-object ((syntax lisp-syntax) (form pathname-form) &key &allow-other-keys)
  
negative.code: (defclass bit-vector-form (form-lexeme complete-form-mixin) ())
  (defclass number-lexeme (form-lexeme complete-form-mixin) ())
  (defclass token-mixin () ())
  (defclass literal-object-form (form-lexeme complete-form-mixin) ())
  (defclass complete-token-lexeme (token-mixin form-lexeme complete-form-mixin) ())
  (defclass multiple-escape-start-lexeme (lisp-lexeme) ())
  (defclass multiple-escape-end-lexeme (lisp-lexeme) ())
  