18 lines
370 B
Racket
18 lines
370 B
Racket
#lang racket
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(require 2htdp/universe)
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(require 2htdp/image)
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(define (f x) (circle 10 'solid 'red))
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(define (g x)
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(cond
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[(= x 0) 1]
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[else (error txt)]))
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(define txt "all questions were #f")
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(with-handlers ([exn? (lambda (e) (unless (string=? (exn-message e) txt) (raise e)))])
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(big-bang 0 (on-tick g) (to-draw f))
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(error 'error-in-tick "test failed"))
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