;; The first three lines of this file were inserted by DrRacket. They record metadata
;; about the language level of this file in a form that our tools can easily process.
#reader(lib "htdp-intermediate-lambda-reader.ss" "lang")((modname week7_w) (read-case-sensitive #t) (teachpacks ((lib "image.ss" "teachpack" "htdp"))) (htdp-settings #(#t constructor repeating-decimal #f #t none #f ((lib "image.ss" "teachpack" "htdp")))))
;; make-secret : nat -> (nat -> symbol)
;; makes up a secret and then returns
;; a function that lets you guess the secret
(define (make-secret n)
  (local [(define secret (random n))]
    (lambda (guess)
      (cond
        [(= guess secret) 'yes]
        [else 'no]))))

;; guess-secret : (nat -> symbol) -> nat
(define (guess-secret secret)
  (guess-helper secret 0))

;; guess-helper : (number -> symbol) number -> number
;; guesses a secret, assuming that the secret is at least n
(define (guess-helper secret n)
  (cond
    [(symbol=? (secret n) 'yes) n]
    [else (guess-helper secret (+ n 1))]))

(define sec3 (make-secret 100000))
(guess-secret sec3)