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17 lines
577 B
Racket
17 lines
577 B
Racket
16 years ago
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#lang scheme/base
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20 years ago
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16 years ago
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(provide (all-defined-out))
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(require syntax/stx)
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;; get-special-action: (syntax-object list) syntax-object syntax-object -> syntax-object
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;; Returns the first action from a rule of the form ((which-special) action)
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(define (get-special-action rules which-special none)
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(cond
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((null? rules) none)
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(else
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(syntax-case (car rules) ()
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(((special) act)
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(and (identifier? #'special) (module-or-top-identifier=? (syntax special) which-special))
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(syntax act))
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(_ (get-special-action (cdr rules) which-special none))))))
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