anchor.diff:      (make-instance 'category-ref
                      :title title)))
   
  -(defun string-to-keyword (str)
  +(defun category-keyword (str)
     (intern (ppcre:regex-replace-all "(\\s)+" (string-upcase str) "-")
             :keyword))
   
  
positive.code:     (let ((node (docutils:make-node 'docutils.nodes:paragraph)))
        (docutils:add-child node
                            (make-instance 'category-content
                                           :title (string-to-keyword title)))
        (docutils:add-child parent node))))
      
negative.code:       (docutils:with-nodes (node doc)
          (typecase node
            (category-ref
             (push (category-keyword (category-ref-title node))
                   categories))))
        categories)))
  
  