19 lines
310 B
Plaintext
19 lines
310 B
Plaintext
(define (make-counter) (let ((var 0)) (lambda () (mutate var (+ 1 var)) var)))
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(define counter1 (make-counter))
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(assert (= (counter1) 1))
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(define counter2 (make-counter))
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(assert (= (counter2) 1))
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(assert (= (counter2) 2))
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(assert (= (counter1) 2))
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(assert (= (counter1) 3))
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(assert (= (counter2) 3))
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