(deftest bryan-string-substitution ()
  (labels ((test-ring-buffer (start stop)
	     (let ((ring (new-buf 5)))
	       (do ((i start (+ i 1)))
		   ((> i stop) (buf-pop ring))
		 (buf-insert i ring)))))
    (check
      (= (+ (* 5 (floor (/ 184 5))) 1) (test-ring-buffer 1 184)))))