18 lines
425 B
Racket
18 lines
425 B
Racket
#lang racket
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(provide acond it)
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(require anaphoric/it
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racket/stxparam)
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(define-syntax (acond stx)
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(syntax-case stx (else)
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[(_ [else . else-body])
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#'(begin . else-body)]
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[(_)
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#'(void)]
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[(_ [condition . body] . rest)
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#'(let ([tmp condition])
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(if tmp
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(syntax-parameterize ([it (make-rename-transformer #'tmp)])
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. body)
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(acond . rest)))])) |