higepon https://blog.hatena.ne.jp/higepon/ higepon blog https://higepon.hatenablog.com/ scheme テストのお供にどうぞ。 (define (make-gensym) (let1 i 0 (lambda () (set! i (+ i 1)) (string->symbol (format "G~d" i))))) (define-macro with-gensym (lambda body (let ([org (gensym)] [ret (gensym)]) `(let1 ,org gensym (set! gensym ,(make-gensym)) (let ((,ret (begin ,@body))) (set! gensym ,org) ,ret))))) (with-gen… 190 <iframe src="https://hatenablog-parts.com/embed?url=https%3A%2F%2Fhigepon.hatenablog.com%2Fentry%2F20080102%2F1199254971" title=" with-gensymマクロ - higepon blog" class="embed-card embed-blogcard" scrolling="no" frameborder="0" style="display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;"></iframe> Hatena Blog https://hatena.blog 2008-01-02 15:22:51 rich https://higepon.hatenablog.com/entry/20080102/1199254971 1.0 100%