19 lines
380 B
Racket
19 lines
380 B
Racket
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#lang racket
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;;; a turing machine implementation
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(define tape (make-hash))
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(define (lookup position)
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(unless (hash-has-key? tape position)
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(hash-set! tape position 0))
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(hash-ref tape position))
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(define turing-machine%
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(class object%
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(init)
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(define tape (make-hash))
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(define head 0)
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(define current-state #f)
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(define state-table)
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(super-new)))
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