Created
January 20, 2011 07:41
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初めてのマクロ(unless)
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| ; unless macro | |
| (define-syntax unless | |
| (syntax-rules () | |
| ((_ pred b1 ...) | |
| (if (not pred) (begin b1 ...))))) | |
| ; 動作テスト | |
| (let ((i 0)) | |
| (unless (= i 1) | |
| (display "i != 0") | |
| (newline))) |
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