;; 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-beginner-reader.ss" "lang")((modname 21.2.1) (read-case-sensitive #t) (teachpacks ()) (htdp-settings #(#t constructor repeating-decimal #f #t none #f ())))
; Worked exercise 21.2.1

; An employee has three parts: name, id, and salary.
; The name is a string, while id and salary are numbers.

(define-struct employee (name id salary))

; make-employee : string(name) number(id) number(salary) -> employee
; employee-name : employee -> string
; employee-id : employee -> number
; employee-salary : employee -> number
; employee? : anything -> boolean

(make-employee "Joe" 348 42995)
(make-employee "Mary" 214 49500)
(define emp1 (make-employee "Bob" 470 36000))
(define emp2 (make-employee "Chris" 471 41000))
(check-expect (employee-name emp1) "Bob")
(check-expect (employee-id emp2) 471)
(check-expect (employee-salary emp2) 41000)
(check-expect (employee-salary (make-employee "Mary" 214 49500))
              49500)
(check-expect (employee? emp1) true)
(check-expect (employee? "Mary") false)

#|
; function-on-employee : a template for functions that take in an employee
(check-expect (function-on-employee emp1) ...)
(check-expect (function-on-employee (make-employee "Joe" 348 42995)) ...)

(define (function-on-employee emp)
  ; emp                      an employee
  ; (employee-name emp)      a string
  ; (employee-id emp)        a number
  ; (employee-salary emp)    a number
  ...
  )

; function-returning-employee : a template for functions that return an employee
(check-expect (function-returning-employee ...) emp1)
(check-expect (function-returning-employee ...)
              (make-employee "Joe" 348 42995))

(define (function-returning-employee ...)
  (make-employee ... ... ...) ; name, id, salary in that order
  )
|#