{"provider_name":"Hatena Blog","author_name":"tmurata","categories":["SICP"],"description":"unless \u306e\u5b9f\u88c5\u3002unless\u3092if\u306b\u5909\u63db\u3059\u308b\u3088\u3046\u306b\u5b9f\u88c5\u3059\u308b \u8ffd\u52a0\u3059\u308b\u624b\u7d9a\u304d (define (unless? exp) (tagged-list? exp 'unless)) (define (unless-predicate exp) (cadr exp)) (define (unless-consequent exp) (caddr exp)) (define (unless-alternative exp) (if (not (null? (cdddr exp))) (cadddr exp) 'false)) ;; make-if\u306fcond->if\u3067\u5b9a\u7fa9\u6e08 (define (unl\u2026","blog_url":"https://tmurata.hatenadiary.org/","title":"SICP\u554f\u984c4.26","image_url":null,"url":"https://tmurata.hatenadiary.org/entry/20100423/1272021811","author_url":"https://blog.hatena.ne.jp/tmurata/","published":"2010-04-23 20:23:31","type":"rich","height":"190","width":"100%","blog_title":"tmurata\u306e\u65e5\u8a18","provider_url":"https://hatena.blog","version":"1.0","html":""}