test.rkt

    #lang racket/gui

    (define my-language 'English)

    (define translations
      #hash([English . "Hello world"]
            [French . "Bonjour le monde"]
            [German . "Hallo Welt"]
            [Greek . "Γειά σου, κόσμε"]
            [Portuguese . "Olá mundo"]
            [Spanish . "Hola mundo"]
            [Thai . "สวัสดีชาวโลก"]))

    (define my-hello-world
      (hash-ref translations my-language
                "hello world"))

    (message-box "" my-hello-world)

    ; Organizing interconnected function definitions with local
    ; [List-of Number] [Number Number -> Boolean]
    ; -> [List-of Number]
    ; produces a version of alon0, sorted according to cmp
    (define (sort-cmp alon0 cmp)
      (local (; [List-of Number] -> [List-of Number]
              ; produces the sorted version of alon
              (define (isort alon)
                (cond
                  [(empty? alon) '()]
                  [else
                   (insert (first alon) (isort (rest alon)))]))

              ; Number [List-of Number] -> [List-of Number]
              ; inserts n into the sorted list of numbers alon
              (define (insert n alon)
                (cond
                  [(empty? alon) (cons n '())]
                  [else (if (cmp n (first alon))
                            (cons n alon)
                            (cons (first alon)
                                  (insert n (rest alon))))])))
        (isort alon0)))