anchor.diff:           (object (reference-object reference)))
       ;; OPT: separate hash table for string objects?
       (if (member (reference-locative-type reference) '(package asdf:system))
  -        (push link (gethash (string object) *object-to-links*))
  +        (push link (gethash (string-upcase (string object)) *object-to-links*))
           (push link (gethash object *object-to-links*)))))
    
  
positive.code:                when (reference-object= object ref)
                   collect ref)
           (unless (stringp object)
             (loop for link in (gethash (string object) *object-to-links*)
                   for ref = (link-reference link)
                   when (reference-object= object ref)
                     collect ref))))
  
negative.code:   `(let ((*local-references* ())
           (*link-to-id* (make-hash-table))
           (*id-to-link* (make-hash-table :test #'equal))
           (*object-to-links* (make-hash-table :test #'equal)))
       (initialize-links ,pages)
       (locally ,@body)))
  
  