27 lines
980 B
Racket
27 lines
980 B
Racket
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(module stxparam-exptime '#%kernel
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(#%require "private/stx.rkt" "private/stxcase-scheme.rkt"
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"private/small-scheme.rkt"
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"private/stxloc.rkt" "private/stxparamkey.rkt")
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(#%provide syntax-parameter-value
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make-parameter-rename-transformer)
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(define-values (syntax-parameter-value)
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(lambda (id)
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(let* ([v (syntax-local-value id (lambda () #f))]
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[v (if (set!-transformer? v)
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(set!-transformer-procedure v)
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v)])
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(unless (syntax-parameter? v)
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(raise-type-error 'syntax-parameter-value "syntax parameter" v))
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(let ([target (syntax-parameter-target v)])
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(syntax-parameter-target-value target)))))
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(define-values (make-parameter-rename-transformer)
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(lambda (id)
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(make-set!-transformer
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(lambda (stx)
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(let ([v (syntax-parameter-value (syntax-local-introduce id))])
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(apply-transformer v stx #'set!)))))))
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