23 lines
686 B
Scheme
23 lines
686 B
Scheme
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(module match scheme/base
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(require mzlib/plt-match
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(for-syntax scheme/base))
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(provide (except-out (all-from-out mzlib/plt-match)
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define-match-expander)
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(rename-out [define-match-expander* define-match-expander]))
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(define-for-syntax (no-old-match-form stx)
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(raise-syntax-error
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#f
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"works only for constructor-based `match' form"
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stx))
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(define-syntax define-match-expander*
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(syntax-rules ()
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[(_ id expr) (define-match-expander id expr)]
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[(_ id expr expr2) (define-match-expander id
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expr
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no-old-match-form
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expr2)])))
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