shigemk2 https://blog.hatena.ne.jp/shigemk2/ by shigemk2 https://www.shigemk2.com/ Emacs Lisp ;; and 返り値は最後に評価したフォームで、いずれかが偽ならばnil (and t t) ; => t (and nil t) ; => nil (and 1 2) ; => 2 (if 1 2) ; => 2 (and 1 2 3) ; => 3 ;; or 返り値は最後に評価したフォームで、すべて偽ならばnil (or nil nil) ; => nil (or nil t) ; => t (or nil 1 2) ; => 1 (or nil 1 2 3) ; => 1 ;; ドモルガン ;; and not not -> not or (and (not t) (not nil))… 190 <iframe src="https://hatenablog-parts.com/embed?url=https%3A%2F%2Fwww.shigemk2.com%2Fentry%2F20120409%2F1333915510" title="and と or - by shigemk2" class="embed-card embed-blogcard" scrolling="no" frameborder="0" style="display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;"></iframe> http://ecx.images-amazon.com/images/I/51Wg39T8KAL.jpg Hatena Blog https://hatena.blog 2012-04-09 05:05:10 rich https://www.shigemk2.com/entry/20120409/1333915510 1.0 100%