{"blog_title":"yohhoy\u306e\u65e5\u8a18","description":"\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u8a00\u8a9eC/C++\u306b\u304a\u3051\u308b\u6761\u4ef6\u6f14\u7b97\u5b50(?:)\u3068\u5de6\u8fba\u5024\u306e\u6271\u3044\u306b\u3064\u3044\u3066\u30e1\u30e2\u3002\u8a00\u8a9e\u4ed5\u69d8\u306e\u9685\u3092\u3064\u3064\u304f\u8a71\u984c\u3067\u3042\u308a\u3001\u901a\u5e38\u306fif\u6587\u3092\u5229\u7528\u3059\u308b\u3079\u304d\u3002\u4e0b\u8a18\u30b3\u30fc\u30c9\u306fC\u3067\u306f\u672a\u5b9a\u7fa9\u52d5\u4f5c(undefined behavior)\u3092\u5f15\u304d\u8d77\u3053\u3059\u304c\u3001C++\u3067\u306fwell-defined\u3067\u3042\u308a\u671f\u5f85\u901a\u308a\u52d5\u4f5c\u3059\u308b\uff08\u5909\u6570a\u306b\u502442\u3092\u4ee3\u5165\uff09\u3002 int a = 0, b = 0, c = 1; (c ? a : b) = 42; \u6b21\u306e\u3088\u3046\u306b\u30dd\u30a4\u30f3\u30bf\u7d4c\u7531\u3068\u3059\u308c\u3070\u3001C/C++\u4e21\u65b9\u3067\u610f\u56f3\u901a\u308a\u52d5\u4f5c\u3059\u308b\u3002 *(c ? &a : &b) = 42; C C99(JTC1/SC22/WG14 N1256) 6.5.15/p4\u3088\u308a\u5f15\u7528\u3002C11(W\u2026","version":"1.0","author_name":"yohhoy","url":"https://yohhoy.hatenadiary.jp/entry/20121119/p1","published":"2012-11-19 00:00:00","author_url":"https://blog.hatena.ne.jp/yohhoy/","image_url":null,"html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fyohhoy.hatenadiary.jp%2Fentry%2F20121119%2Fp1\" title=\"\u6761\u4ef6\u6f14\u7b97\u5b50\u3068\u5de6\u8fba\u5024\u306e\u6271\u3044\u306e\u5dee - yohhoy\u306e\u65e5\u8a18\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","type":"rich","categories":["C","C++"],"title":"\u6761\u4ef6\u6f14\u7b97\u5b50\u3068\u5de6\u8fba\u5024\u306e\u6271\u3044\u306e\u5dee","height":"190","provider_name":"Hatena Blog","provider_url":"https://hatena.blog","blog_url":"https://yohhoy.hatenadiary.jp/","width":"100%"}