(define-struct boa (name length food))
;; a Boa is a (make-boa String Natural String)
;; interpretation:  represents a boa constrictor where
;;   name is the boa's name
;;   length is its length (in inches)
;;   food is the boa's favorite food

;; examples
(define MOLLY (make-boa "Molly" 21 "grapes"))
(define HOMER (make-boa "Homer" 35 "donuts"))

;; selectors
;; boa-name:  Boa -> String
;; consumes a boa and produces the boa's name

;; boa-length:  Boa -> Natural

;; boa-food:  Boa -> String

;; constructor
;; make-boa:  String Natural String -> Boa

;; predicate
;; boa?:  anything -> Boolean


;; boa-fit-cage?:  Boa Natural -> Boolean
;; consumes a boa and the length of a cage and produces true if the length of
;; the boa is less than the length of the cage (produces false otherwise)
(define (boa-fit-cage? a-boa cage-length)
  (< (boa-length a-boa) cage-length))
  

;; test
(check-expect (boa-fit-cage? MOLLY 30) true)
(check-expect (boa-fit-cage? MOLLY 21) false)
(check-expect (boa-fit-cage? (make-boa "Jack" 17 "popcorn") 10) false)