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@ -17,12 +17,12 @@
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(define stack empty)
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(define stack empty)
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(define (pop-stack!)
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(define (pop-stack!)
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(define item (first stack))
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(define arg (first stack))
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(set! stack (rest stack))
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(set! stack (rest stack))
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item)
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arg)
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(define (push-stack! item)
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(define (push-stack! arg)
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(set! stack (cons item stack)))
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(set! stack (cons arg stack)))
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(define (handle [arg #f])
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(define (handle [arg #f])
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(cond
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(cond
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