(define globalSet #f)
(define globalGet #f)

(define (main)
  (define a 0)

  (define (set)
    (set! a 1))
  (define (get)
    (display a)
    (newline))

  (set! globalSet set)
  (set! globalGet get))

(main)
(globalGet)
(globalSet)
(globalGet)