Guided pluralize functions

pluralize.scs

; Problem: Design a function that pluralizes a given word.
; (Pluralize means to convert the word to its plural form.)
; For simplicity you may assume that just adding s is enough to pluralize a word
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;; What is an appropriate signature for this function?


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;; Which of the following purpose statements is best?
;; NOTE: Delete the one's you think are not good enought.

;; Pluralize s.
;; Produce plural string.
;; Add "s".
;; Produce the given string with "s" added to the end.


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;  Which of the following stubs is best?
;; NOTE: Remove ;; from the one you need fit's

;; (define (pluralize str) 0)
;; (define (string str) str)
;; (define (pluralize str) "")
;; (define (longer str) 1)

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;; Which of the following check-expects is appropriate?
;; NOTE: Uncomment(remove ;;) all that apply, delete the rest.

;; (check-expect (pluralize "cat") "s")
;; (check-expect (pluralize "cat") "cat")
;; (check-expect (pluralize "dog") "dogs")
;; (check-expect (pluralize "grass") "grasss")

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;; Continuing with the given problem, we now have a signature, purpose, stub and
;; several examples. Here is the template for this function.


(define (pluralize str)
 (... str))


;; code the body by replacing (... str) with the proper body.