; Load the guessing game for its utiltities.
(load "/home/rebelsky/Web/Courses/CS151/2006F/Examples/guessing-game.scm")

(define guess-name
  (lambda ()
    (letrec ((kernel
              (lambda (lb ub)
                (if (> lb ub)
                    (print-line "You win!  I've run out of names.")
                    (let* ((mid (quotient (+ lb ub) 2))
                           (midname (vector-ref names mid)))
                      (cond 
                        ((yes-or-no? (string-append "Is the name "
                                                    midname
                                                    "?"))
                         (print-line "I win!"))
                        ((yes-or-no? (string-append "Does the name alphabetically precede " midname "?")) (kernel lb (- mid 1)))
                        (else (kernel (+ mid 1) ub))))))))
      (print-line "Think of a name and I'll try to guess it.")
      (kernel 0 (- (vector-length names) 1))
      (if (yes-or-no? "Play again?")
          (guess-name)
          (print-line "Thanks for playing.")))))