anchor.diff:                           (make-instance 'minibuffer
                                           :input-prompt "Delete bookmark(s):"
                                           :multi-selection-p t
  -                                        :completion-function #'bookmark-completion-filter)))
  +                                        :completion-function (bookmark-completion-filter))))
       (setf (bookmarks-data *interface*)
             (set-difference (bookmarks-data *interface*) entries :test #'equals))))
   
  
positive.code:       (setf (tags entry) (sort tags #'string<))
        (push entry (bookmarks-data *interface*)))))
  
  (defun bookmark-completion-filter (input)
    ;; TODO: Filter by tags.
    (fuzzy-match input (bookmarks-data *interface*)))
  
  (defun tag-completion-filter (&key with-empty-tag)
    "When with-empty-tag is non-nil, insert the empty string as the first tag.
  
negative.code:   (with-result (entry (read-from-minibuffer
                         (make-instance 'minibuffer
                                        :input-prompt "Open bookmark:"
                                        :completion-function (bookmark-completion-filter))))
      ;; TODO: Add support for multiple bookmarks?
      (set-url (url entry) :buffer (current-buffer) :raw-url-p t)))
  
  