12 lines
292 B
Racket
12 lines
292 B
Racket
#lang scheme
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(require 2htdp/universe)
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(define txt "expected to return a scene but this is a string")
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(with-handlers ((exn? (lambda (e) (unless (string=? (exn-message e) txt) (raise e)))))
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(big-bang 0
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(on-tick add1)
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(to-draw (lambda (w) (error txt)))))
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