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#lang debug racket/base
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(require racket/list)
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(provide (all-defined-out))
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(define (split-metas tree meta-key)
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(define datums (flatten (if (syntax? tree) (syntax->datum tree) tree)))
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(if (>= (length datums) 3)
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(for/hasheq ([name (in-list datums)]
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[k (in-list (cdr datums))]
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[v (in-list (cddr datums))]
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#:when (eq? name meta-key))
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(values k v))
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(hasheq)))
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(module+ test
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(require rackunit)
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(check-equal? (split-metas '(root) 'define-meta) (hasheq))
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(check-equal? (split-metas '(root (div #:kw #f (define-meta foo "bar") "hi") "zim" (define-meta foo "boing") "zam") 'define-meta) '#hasheq((foo . "boing")))
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(check-equal? (split-metas #'(root (define-meta dog "Roxy") (define-meta dog "Lex")) 'define-meta) '#hasheq((dog . "Lex")))
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(check-equal? (split-metas #'(root (define-meta dog "Roxy") (div (define-meta dog "Lex"))) 'define-meta) '#hasheq((dog . "Lex"))))
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