;; 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 shapes) (read-case-sensitive #t) (teachpacks ()) (htdp-settings #(#t constructor repeating-decimal #f #t none #f ())))

;; to represent a cartesian point in a plane
;; A CartPt is (make-cart-pt Number Number)
(define-struct cart-pt (x y))

;; to represent a circle
;; A Circle is (make-circle CartPt Number String)
(define-struct circle (loc rad color))


(define p50x50y (make-posn 50 50))
(define p20x40y (make-posn 20 40))
(define p30x40y (make-posn 30 40))

(define circle1 (make-circle (make-posn 50 50) 50 "red"))
(define circle2 (make-circle (make-posn 20 40) 10 "green"))
(define circle3 (make-circle (make-posn 30 40) 20 "blue"))


(check-expect circle1 (make-circle p50x50y 50 "red")) 
(check-expect circle2 (make-circle p20x40y 10 "green")) 
(check-expect circle3 (make-circle p30x40y 20 "blue"))