25 lines
825 B
Scheme
25 lines
825 B
Scheme
(module break mzscheme
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(require (lib "contract.ss"))
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(provide current-breakpoint-handler)
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(define (default-current-breakpoint-handler)
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(error 'default-current-breakpoint-handler
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"The current-breakpoint-handler parameter has not yet been set in this thread."))
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(define current-breakpoint-handler
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(make-parameter default-current-breakpoint-handler
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(lambda (new-handler)
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(if (and (procedure? new-handler)
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(procedure-arity-includes? new-handler 0))
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new-handler
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(error 'current-breakpoint-handler "Bad value for current-breakpoint-handler: ~e" new-handler)))))
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(provide/contract [break (-> any)])
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(define (break)
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((current-breakpoint-handler))))
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