anchor.diff:                   `(:setup-function ,setup-function)
                    '())
              ,@(if explicit-cleanup-function
  -                 `(:cleanup-function ,cleanup-function)
  -                 '())
  +                `(:cleanup-function ,cleanup-function)
  +                '())
  +           ,@(if explicit-changed-callback
  +                `(:changed-callback ,changed-callback)
  +                '())
              ,@(if explicit-empty-complete-immediate
                    `(:empty-complete-immediate ,empty-complete-immediate)
                    '())
  
positive.code:                          (setf (ps:chain document (get-element-by-id "input-buffer") |innerHTML|)
                                 (ps:lisp input-text))
                           (setf (ps:chain document (get-element-by-id "completions") |innerHTML|)
                                 (ps:lisp completion-html)))))))
  
  (define-command select-next (&optional (minibuffer (current-minibuffer)))
    "Select next entry in minibuffer."
  
negative.code:                           (callback-buffer nil explicit-callback-buffer)
                            (setup-function nil explicit-setup-function)
                            (cleanup-function nil explicit-cleanup-function)
                            (changed-callback nil explicit-changed-callback)
                            (empty-complete-immediate nil explicit-empty-complete-immediate)
                            (input-prompt nil explicit-input-prompt)
                            (input-buffer nil explicit-input-buffer)
  