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;;; -*-Scheme-*-
(define (make-cell)
(call-with-current-continuation
(lambda (return-from-make-cell)
(letrec ((state
(call-with-current-continuation
(lambda (return-new-state)
(return-from-make-cell
(lambda (op)
(case op
((set)
(lambda (value)
(call-with-current-continuation
(lambda (return-from-access)
(return-new-state
(list value return-from-access))))))
((get) (car state)))))))))
((cadr state) 'done)))))
(define c (make-cell))
(print ((c 'set) 99))
(print (c 'get))
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