(load-relative "sig.ss")
(unit/sig ui^
  (import struct^)

  (define display-move
    (lambda (move)
      (let ((num  (move-num move))
	    (x    (move-x move))
	    (y    (move-y move))
	    (sec  (move-time move)))
	(printf "Player ~s moves to (~s, ~s) in time ~s ~n"
		num y x sec))))

  ; enforce arity 1
  (define (show-mesg str) (printf str)))