(module a1 mzscheme
  
  (provide (all-defined))
  
  (define-struct s (args body f ns))
  
  (define-syntax def
    (syntax-rules ()
      ((d name args body ...)
       (define name (make-s 'args
                            '(body ...)
                            #f
                            (current-namespace))))))
  
  (define (act an-s)
    (parameterize ((current-namespace (s-ns an-s)))
      (set-s-f! an-s
                (eval `(lambda ,(s-args an-s)
                         ,@(s-body an-s))))))
  
  (define (app an-s . args)
    (apply (s-f an-s) args))
  
  (define (my-f3 x) (* x x))
  
  )