11 lines
198 B
Racket
11 lines
198 B
Racket
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#lang racket/base
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(provide make-counter)
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(define (make-counter [start-value 0])
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(define next-value start-value)
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(lambda ()
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(let ((v next-value))
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(set! next-value (+ v 1))
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v)))
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