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31 lines
921 B
Scheme
31 lines
921 B
Scheme
#cs
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(module parser-actions mzscheme
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;; The entries into the action table
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(provide shift? reduce? accept?
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shift-state reduce-prod-num reduce-lhs-num reduce-rhs-length
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make-shift make-reduce make-accept)
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;; action = (shift int)
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;; | (reduce int int int)
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;; | (accept)
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;; | int>=0
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;; | #f
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(define (shift? x) (and (integer? x) (< x 0)))
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(define (make-shift x) (- (+ x 1)))
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(define (shift-state x) (- (+ x 1)))
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(define reduce? vector?)
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(define make-reduce vector)
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(define (reduce-prod-num x) (vector-ref x 0))
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(define (reduce-lhs-num x) (vector-ref x 1))
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(define (reduce-rhs-length x) (vector-ref x 2))
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(define (accept? x) (eq? x 'accept))
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(define (make-accept) 'accept)
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;(define-struct shift (state) (make-inspector))
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;(define-struct reduce (prod-num lhs-num rhs-length) (make-inspector))
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;(define-struct accept () (make-inspector))
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)
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