(define-record-type reinitializer :reinitializer
  (make-reinitializer thunk)
  reinitializer?
  (thunk reinitializer-thunk))

(define-record-discloser :reinitializer
  (lambda (r)
    (list 'reinitializer (reinitializer-thunk r))))

(define-record-resumer :reinitializer
  (lambda (r)
    ((reinitializer-thunk r))))