{"id":656,"date":"2014-04-13T23:56:42","date_gmt":"2014-04-13T14:56:42","guid":{"rendered":"http:\/\/dev.activebasic.com\/egtra\/?p=656"},"modified":"2014-04-13T23:56:42","modified_gmt":"2014-04-13T14:56:42","slug":"friend%e3%81%a8template%e3%81%ab%e3%82%88%e3%82%8bvisual-c%e3%81%a7%e3%81%97%e3%81%8b%e5%8b%95%e3%81%8b%e3%81%aa%e3%81%84%e3%82%b3%e3%83%bc%e3%83%89","status":"publish","type":"post","link":"https:\/\/dev.activebasic.com\/egtra\/2014\/04\/13\/656\/","title":{"rendered":"friend\u3068template\u306b\u3088\u308bVisual C++\u3067\u3057\u304b\u52d5\u304b\u306a\u3044\u30b3\u30fc\u30c9"},"content":{"rendered":"<p>\u4eca\u65e5\u306e\u30c6\u30fc\u30de\u306f\u3001Visual C++\u3060\u3051\u3067\u30b3\u30f3\u30d1\u30a4\u30eb\u30fb\u5b9f\u884c\u3067\u304d\u308b\u4e0d\u601d\u8b70\u306a\u30b3\u30fc\u30c9\u3067\u3059\u3002\uff08nullptr\u3055\u3048\u76f4\u305b\u3070\uff092005\u304b\u30892013\u307e\u3067\u3044\u305a\u308c\u3067\u3082\u901a\u7528\u3057\u307e\u3059\u3002<\/p>\n<pre lang=\"cpp\">\r\n#include <iostream>\r\n\r\nvoid f() { std::cout << \"f\" << std::endl; }\r\nvoid g() { std::cout << \"g\" << std::endl; }\r\n\r\ntemplate<class T>\r\nclass TypeF\r\n{\r\n  friend void InvokeImpl(T*)\r\n  {\r\n    f();\r\n  }\r\n};\r\n\r\ntemplate<class T>\r\nclass TypeG\r\n{\r\n  friend void InvokeImpl(T*)\r\n  {\r\n    g();\r\n  }\r\n};\r\n\r\ntemplate<class T>\r\nclass Selector\r\n{\r\n  friend void InvokeImpl(T*);\r\n\r\npublic:\r\n  static void Invoke()\r\n  {\r\n    return InvokeImpl(static_cast<T*>(nullptr));\r\n  }\r\n};\r\n\r\n\/\/ \u3053\u3053\u304b\u3089\u5229\u7528\u4f8b\r\n\r\nstruct Hoge;\r\nstruct Piyo;\r\nstruct Fuga;\r\n\r\ntemplate class TypeF<Hoge>;\r\ntemplate class TypeG<Piyo>;\r\ntemplate class TypeF<Fuga>;\r\n\r\nint main()\r\n{\r\n  Selector<Hoge>::Invoke();\r\n  Selector<Piyo>::Invoke();\r\n  Selector<Fuga>::Invoke();\r\n}\r\n<\/pre>\n<p>\u3053\u308c\u3092\u5b9f\u884c\u3059\u308b\u3068\u3053\u3046\u3044\u3046\u51fa\u529b\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n<pre>\r\nf\r\ng\r\nf\r\n<\/pre>\n<p>\u3053\u306e\u30b3\u30fc\u30c9\u306f\u300c\u578b\u306b\u3088\u3063\u3066\u95a2\u6570f\u3068g\u3092\u547c\u3073\u5206\u3051\u308b\u300d\u3068\u3044\u3046\u3082\u306e\u3067\u3059\u3002<\/p>\n<p>\u5229\u7528\u8005\u306f\u3001\u81ea\u5206\u306e\u4f5c\u3063\u305f\u578b\u3092\u5b9f\u5f15\u6570\u306bTypeF\u307e\u305f\u306fTypeG\u3092\u660e\u793a\u7684\u5b9f\u4f53\u5316\u3057\u307e\u3059\u3002Selector::Invoke\u306b\u578b\u3092\u4e0e\u3048\u3066\u547c\u3073\u51fa\u3059\u3068\u3001\u660e\u793a\u7684\u5b9f\u4f53\u5316\u3057\u305f\u307b\u3046\u306eInvokeImpl\u304c\u547c\u3073\u51fa\u3055\u308c\u308b\u3068\u3044\u3046\u304b\u3089\u304f\u308a\u3067\u3059\u3002\u3053\u306etemplate\u3068friend\u306e\u7d44\u307f\u5408\u308f\u305b\u65b9\u304cGCC\u3084Clang\u3067\u306f\u3046\u307e\u304f\u3044\u304d\u307e\u305b\u3093\u3067\u3057\u305f\u3002<\/p>\n<p>\u3053\u308c\u306b\u76f8\u5f53\u3059\u308b\u3053\u3068\u3092\u3084\u308b\u3060\u3051\u306a\u3089\u3001\u307b\u304b\u306b\u3084\u308a\u3088\u3046\uff08GCC\u3067\u3082Clang\u3067\u3082\u3067\u304d\u308b\u65b9\u6cd5\uff09\u306f\u3042\u308a\u307e\u3059\u3002\u5358\u306b\u3053\u3046\u3044\u3046\u65b9\u6cd5\u3082\u3042\u308b\u3068\u3044\u3046\u7d39\u4ecb\u3067\u3057\u305f\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>template\u3068friend\u306e\u7d44\u307f\u5408\u308f\u305b\u3067\u3001Visual C++\u3067\u3057\u304b\u30b3\u30f3\u30d1\u30a4\u30eb\u3067\u304d\u306a\u3044\u30b3\u30fc\u30c9\u3092\u898b\u3064\u3051\u305f\u3068\u3044\u3046\u5185\u5bb9\u3067\u3059\u3002<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[5,12],"tags":[],"class_list":["post-656","post","type-post","status-publish","format-standard","hentry","category-cpp","category-vc"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v23.0 - 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