13 lines
414 B
Racket
13 lines
414 B
Racket
#lang racket
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(require 2htdp/universe 2htdp/image)
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(with-handlers ((exn? (lambda (w)
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(unless (string=? "stop!: the universe stopped: 3" (exn-message w))
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(raise w)))))
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(universe 0
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(on-tick (lambda (w) (make-bundle (add1 w) '() '())) 1/28 3)
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(on-msg void)
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(on-new cons))
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(error "the universe didn't stop properly"))
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