cute-cursor.el

;;(cute-cursor t)   ;開始
;;(cute-cursor nil) ;終了

(require 'cl)

(lexical-let ((interval 0.05)
              (colors '("red" "green" "blue" "yellow" "purple" "magenta" "cyan"))
              (cursor-nth 0)
              (timer nil))
  (defun cute-cursor (flag)
    "Start toggling cursor color when flag is true."
    (cond
     ((and flag timer) (cute-cursor nil))
     (flag (setq timer (run-with-timer interval interval
                                       (lambda ()
                                         (set-cursor-color (nth cursor-nth colors))
                                         (incf cursor-nth)
                                         (if (>= cursor-nth (length colors))
                                           (setq cursor-nth 0)))))
           (blink-cursor-mode 0))
     (timer (cancel-timer timer)
            (setq timer nil)))))