{"provider_url":"https://hatena.blog","blog_title":"IT\u6226\u8a18","published":"2009-07-07 14:04:25","provider_name":"Hatena Blog","width":"100%","version":"1.0","blog_url":"https://amachang.hatenablog.com/","type":"rich","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Famachang.hatenablog.com%2Fentry%2F20090707%2F1246943065\" title=\" boost::is_convertible \u306f\u3069\u3046\u3084\u3063\u3066\u308b\u304b - IT\u6226\u8a18\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","url":"https://amachang.hatenablog.com/entry/20090707/1246943065","author_url":"https://blog.hatena.ne.jp/amachang/","image_url":null,"categories":["C++"],"author_name":"amachang","height":"190","title":" boost::is_convertible \u306f\u3069\u3046\u3084\u3063\u3066\u308b\u304b","description":"\u6982\u306d\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u611f\u3058 template <typename From, typename To> struct is_convertible_basic_impl { // 2 \u3064\u306e\u540c\u540d\u95a2\u6570\u3092\u4f5c\u3063\u3066 static no_type _m_check(...); static yes_type _m_check(To); // \u95a2\u6570\u306e\u623b\u308a\u5024\u306e\u578b\u3092\u898b\u308b\uff08\u3069\u3063\u3061\u306e\u95a2\u6570\u304c\u4f7f\u308f\u308c\u308b\u304b\u3092\u898b\u308b\uff09 static bool value = sizeof( _m_check(From) ) == sizeof(yes_type); }; \u3053\u308c\u3067 From \u578b\u306e\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u304c To \u578b\u306b\u4ee3\u5165\u3067\u304d\u308b\u304b\u304c\u3001\u30b3\u30f3\u30d1\u30a4\u30eb\u6642\u306b\u2026"}