#lang racket/gui

(define my-param (make-parameter 'uninitilized))

(define (create-frame)
  (letrec ([my-frame (new frame% [label "test-frame"])]
           [my-button (new button%
                           [label "push me"]
                           [parent my-frame]
                           [callback (λ (b e) (printf "callback called: ~a~n" (my-param)))])])
    (send my-frame show #t)
    my-frame))

(printf "outside parameterize: ~a~n" (my-param))
(parameterize ([my-param 'initilized])
  (printf "inside parameterize: ~a~n" (my-param))
  (create-frame))