anchor.diff:        (if activate
             ;; TODO: Shall we pass args to `make-instance' or `enable'?
             ;; Have 2 args parameters?
  -          (enable (or existing-instance
  -                      (apply #'make-instance mode-sym
  -                             :buffer buffer
  -                             args)))
  +          (let ((mode (or existing-instance
  +                          (apply #'make-instance mode-sym
  +                                 :buffer buffer
  +                                 args))))
  +            (enable mode)
  +            (echo "~@(~a~) mode enabled." mode))
             (when existing-instance
  -            (disable existing-instance))))))
  +            (disable existing-instance)
  +            (echo "~@(~a~) mode disabled." existing-instance))))))
   
   (define-command toggle-modes (&key (buffer (current-buffer)))
     "Enable marked modes, disable unmarked modes for BUFFER."
  
positive.code:              (eq (first (active-prompt-buffers (window buffer)))
                   buffer))
          (prompt-render-prompt buffer)
          (print-status))
      (unless (prompt-buffer-p buffer) (echo "~@(~a~) mode enabled." mode)))
    (log:debug "~@(~a~) mode enabled." mode))
  
  (export-always 'disable)
  (defgeneric disable (mode &key &allow-other-keys)
  
negative.code:              (eq (first (active-prompt-buffers (window buffer)))
                   buffer))
          (prompt-render-prompt buffer)
          (print-status))))
  
  (export-always 'define-mode)
  (defmacro define-mode (name direct-superclasses &body body)
  