{"id":47,"date":"2021-05-23T13:20:40","date_gmt":"2021-05-23T05:20:40","guid":{"rendered":"https:\/\/blog.cauchyschwarz.com\/?p=47"},"modified":"2021-05-24T09:37:26","modified_gmt":"2021-05-24T01:37:26","slug":"%e6%b7%b1%e5%85%a5%e5%ba%94%e7%94%a8c11%e7%ac%94%e8%ae%b0-%e7%ac%ac11%e7%ab%a0","status":"publish","type":"post","link":"https:\/\/blog.cauchyschwarz.com\/?p=47","title":{"rendered":"\u6df1\u5165\u5e94\u7528C++11\u7b14\u8bb0 \u7b2c11\u7ae0"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">\u4f7f\u7528C++11\u5f00\u53d1\u4e00\u4e2a\u8f7b\u91cf\u7ea7\u7684IoC\u5bb9\u5668<\/h2>\n\n\n\n<p>\u5728\u5de5\u4f5c\u4e2d\u9047\u5230\u4e00\u4e2a\u4e0eIoC\u5bb9\u5668\u7c7b\u4f3c\u7684\u95ee\u9898\uff0c\u90a3\u5c31\u662f\u4e0d\u540c\u7ebf\u7a0b\u4e4b\u95f4\u901a\u4fe1\u7684\u65f6\u5019\u60f3\u901a\u8fc7\u540c\u4e00\u4e2a\u961f\u5217\u4f20\u9012\u4e0d\u540c\u7c7b\u578b\u7684\u6570\u636e\uff0c\u800c\u8fd9\u4e9b\u6570\u636e\u7684\u7c7b\u578b\u5e76\u6ca1\u6709\u7ee7\u627f\u5173\u7cfb\uff0c\u4e0d\u5c5e\u4e8e\u540c\u4e00\u4e2a\u57fa\u7c7b\u7684\u5b50\u7c7b\u3002\u6700\u5148\u60f3\u5230\u7684\u662f\u4f7f\u7528union\u6765\u4fdd\u5b58\u4e0d\u540c\u7c7b\u578b\u3002\u7136\u800c\u4f7f\u7528union\u6765\u4fdd\u5b58\u975ePOD\u7c7b\u578b\u7684\u6570\u636e\u662f\u6709\u95ee\u9898\u7684\uff0c\u56e0\u4e3aunion\u5728\u6784\u9020\u548c\u6790\u6784\u7684\u65f6\u5019\u662f\u4e0d\u77e5\u9053\u8981\u600e\u4e48\u5904\u7406union\u91cc\u7684\u6570\u636e\uff0cunion\u5e76\u4e0d\u77e5\u9053\u5176\u4e2d\u4fdd\u5b58\u7684\u6570\u636e\u5230\u5e95\u662f\u54ea\u4e2a\u7c7b\u578b\u7684\uff0c\u81ea\u5df1\u52a8\u624b\u5c1d\u8bd5\u5199\u4e00\u4e2a\u8fd9\u6837\u7684union\uff0c\u7f16\u8bd1\u7684\u65f6\u5019\u5c31\u4f1a\u62a5\u9519\uff0c\u63d0\u793aunion\u7684\u6784\u9020\u51fd\u6570\u548c\u6790\u6784\u51fd\u6570\u662fdeleted\uff0c\u56e0\u6b64\u9700\u8981\u81ea\u5df1\u624b\u52a8\u6dfb\u52a0union\u7684\u6784\u9020\u51fd\u6570\u7684\u5b9e\u73b0\u3002\u540c\u6837\u7684\u5bf9\u4e8eunion\u7684\u62f7\u8d1d\u51fd\u6570\u4e5f\u4f1a\u5b58\u5728\u95ee\u9898\uff0c\u9700\u8981\u81ea\u5df1\u6dfb\u52a0union\u62f7\u8d1d\u51fd\u6570\u7684\u5b9e\u73b0\u907f\u514d\u6d45\u62f7\u8d1d\u5e26\u6765\u7684\u95ee\u9898\u3002\u53e6\u5916union\u91cc\u6ca1\u6709\u5730\u65b9\u4fdd\u5b58\u5f53\u524dactive\u7684\u7c7b\u578b\uff0c\u56e0\u6b64\u9700\u8981\u5728union\u4e4b\u5916\u589e\u52a0\u53d8\u91cf\u6765\u4fdd\u5b58union\u91cc\u6709\u6548\u7684\u7c7b\u578b\uff0c\u4e8e\u662f\u5c31\u8981\u81ea\u5df1\u5b9e\u73b0\u4e00\u4e2atagged union\u7c7b\u6765\u628a\u8fd9\u4e2aunion\u7ed9\u5305\u8d77\u6765\u3002\u5728\u5b9e\u73b0\u8fd9\u4e2atagged union\u7c7b\u7684\u8fc7\u7a0b\u4e2d\uff0c\u4e5f\u4f1a\u7528\u5230\u4e00\u70b9\u5e73\u65f6\u4e0d\u7528\u7684\u4e1c\u897f\uff0c\u90a3\u5c31\u662finplacement new\u548c\u624b\u52a8\u8c03\u7528\u6790\u6784\u51fd\u6570\u3002\u5177\u4f53\u5982\u4f55\u5b9e\u73b0\u8fd9\u6837\u4e00\u4e2a\u7b80\u5355\u7684tagged union\u7c7b\uff0c\u53ef\u4ee5\u8bfb<a href=\"https:\/\/zhuanlan.zhihu.com\/p\/56161425\">\u77e5\u4e4e\u4e0a\u7684\u8fd9\u7bc7\u6587\u7ae0<\/a>\u3002\u4f46\u662f\u8fd9\u6837\u4e00\u4e2a\u7b80\u5355\u7684tagged union\u7c7b\u662f\u4e0d\u591f\u7684\uff0c\u56e0\u4e3a\u5982\u679c\u6211\u4eec\u60f3\u91cd\u7528\u4ee3\u7801\uff0c\u6539\u53d8\u5b58\u653e\u5728\u8fd9\u4e2aunion\u91cc\u7684\u7c7b\u578b\uff0c\u90a3\u4e48\u5c31\u5fc5\u987b\u7528\u6a21\u677f\u6765\u62bd\u8c61\u548c\u7b80\u5316\u6211\u4eec\u7684\u4ee3\u7801\uff0c\u6211\u4eec\u4e0d\u60f3\u5f80\u8fd9\u4e2atagged union\u91cc\u65b0\u589e\u4e00\u4e2a\u7c7b\u578b\u65f6\u5c31\u8981\u51e0\u4e4e\u628a\u8fd9\u4e2atagged union\u7c7b\u7684\u6bcf\u4e2a\u51fd\u6570\u5b9e\u73b0\u90fd\u6539\u4e00\u904d\u3002\u4e8e\u662f\u6211\u4eec\u7684\u9700\u6c42\u5b9e\u9645\u4e0a\u5c31\u53d8\u6210\u4e86\u5b9e\u73b0c++17\u91cc\u7684variant\u3002\u53ef\u4ee5\u53bb\u7ffbc++17 variant\u7684\u5b9e\u73b0\uff0c\u6216\u8005\u53c2\u8003\u8fd9\u7bc7<a href=\"https:\/\/dev.to\/aka_dude\/let-s-write-tagged-union-in-c-1chf\">\u535a\u5ba2<\/a>\u3002variant\u65b9\u6848\u7684\u7f3a\u70b9(\u4e5f\u53ef\u4ee5\u8bf4\u662f\u4f18\u70b9)\u662f\u9700\u8981\u5728\u4e00\u5f00\u59cb\u7684\u6a21\u677f\u53c2\u6570\u91cc\u5217\u51fa\u6240\u6709\u53ef\u80fd\u4f5c\u4e3a\u6210\u5458\u7684\u7c7b\u578b\u3002\u9664\u4e86\u4f7f\u7528union\u6765\u4fdd\u5b58\u4e0d\u540c\u7c7b\u578b\uff0c\u4e5f\u53ef\u4ee5\u4f7f\u7528<code>void*<\/code>\u6765\u4fdd\u5b58\uff0c\u8fd9\u5176\u5b9e\u5c31\u662fc++17\u91cc\u65b0\u589e\u7684any\u4e86\u3002variant\u53ef\u4ee5\u770b\u4f5c\u662f\u6539\u8fdb\u7684union\uff0cany\u53ef\u4ee5\u770b\u4f5c\u662f\u6539\u8fdb\u7684<code>void *<\/code>\uff0c\u4e0d\u76f4\u63a5\u4f7f\u7528union\u548c<code>void*<\/code>\u9664\u4e86\u524d\u9762\u8bb2\u7684\u6784\u9020\u3001\u6790\u6784\u51fd\u6570\u3001\u62f7\u8d1d\u51fd\u6570\u5e26\u6765\u7684\u95ee\u9898\uff0c\u8fd8\u6709\u5c31\u662f\u6a21\u677f\u7684\u95ee\u9898\uff0c\u6211\u4eec\u4e0d\u60f3\u7528\u786c\u7f16\u7801\uff0c\u6211\u4eec\u60f3\u8981\u4e00\u4e2a\u65b9\u4fbf\u597d\u7528\u53ef\u91cd\u7528\u6027\u9ad8\u7684union\u548c<code>void*<\/code>\uff0c\u4e8e\u662f\u5c31\u6709\u4e86variant\u548cany\u3002\u5173\u4e8evariant\u548cany\u7684\u533a\u522b\uff0c\u53ef\u4ee5\u67e5\u770b<a href=\"https:\/\/stackoverflow.com\/a\/56304067\/5357784\">stackoverflow\u4e0a\u7684\u4e00\u4e2a\u8ba8\u8bba<\/a>\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>variant\u652f\u6301\u7684\u7c7b\u578b\u662f\u4e00\u5f00\u59cb\u7f16\u8bd1\u524d\u5c31\u5b9a\u6b7b\u7684\uff0cany\u662f\u52a8\u6001\u7684\uff0c\u4ec0\u4e48\u7c7b\u578b\u90fd\u53ef\u4ee5<\/li><li>variant\u7c7b\u578b\u68c0\u67e5\u662fO(1)\u590d\u6742\u5ea6\uff0cany\u7c7b\u578b\u68c0\u67e5\u662fO(n)<\/li><li>variant\u7684\u7c7b\u578b\u58f0\u660e\u53ef\u4ee5\u8ba9\u4eba\u66f4\u597d\u5730\u7406\u89e3\u6253\u7b97\u7528\u8fd9\u4e2avariant\u4fdd\u5b58\u54ea\u4e9b\u7c7b\u578b\u7684\u4e1c\u897f<\/li><\/ul>\n\n\n\n<p>\u9664\u975e\u5fc5\u8981\uff0c\u4f18\u5148\u4f7f\u7528variant\u3002<\/p>\n\n\n\n<p>\u56de\u5230\u4e66\u4e2d\u6240\u8bb2\u7684\u5185\u5bb9\uff0c\u4f5c\u8005\u8981\u89e3\u51b3\u7684\u95ee\u9898\u662f\u5b9e\u73b0\u4e00\u4e2a\u5de5\u5382\u7c7b\u6216\u8005\u51fd\u6570\uff0c\u8fd9\u4e2a\u5de5\u5382\u53ef\u4ee5\u8fd4\u56de\u4e0d\u540c\u7c7b\u578b\u7684\u5bf9\u8c61\uff0c\u800c\u4e14\u8981\u8fd4\u56de\u7684\u7c7b\u578b\u4e4b\u95f4\u53ef\u80fd\u6ca1\u6709\u516c\u5171\u7684\u57fa\u7c7b\u3002\u53e6\u5916\u5e0c\u671b\u4fee\u6539\u5de5\u5382\u80fd\u591f\u8fd4\u56de\u7684\u7c7b\u578b\u65f6\u4e0d\u9700\u8981\u4fee\u6539\u8fd9\u4e2a\u5de5\u5382\u7c7b\u6216\u8005\u51fd\u6570\u7684\u4ee3\u7801\uff0c\u5b9e\u73b0\u53ef\u914d\u7f6e\u6216\u8005\u6240\u8c13\u7684\u63a7\u5236\u53cd\u8f6c(Inversion of Control, IoC)\u3002<br>\u8981\u8fd4\u56de\u4e0d\u540c\u7684\u7c7b\u578b\u6d89\u53ca\u5230\u7c7b\u578b\u64e6\u9664\u7684\u6280\u672f\uff0c\u4f5c\u8005\u603b\u7ed3\u4e86\u4e0b\u7c7b\u578b\u64e6\u9664\u7684\u5e38\u7528\u65b9\u5f0f\uff1a<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>\u901a\u8fc7\u591a\u6001<br>\u7f3a\u70b9\u662f\u8981\u8fd4\u56de\u7684\u4e0d\u540c\u7c7b\u578b\u5fc5\u987b\u7ee7\u627f\u4e8e\u540c\u4e00\u4e2a\u57fa\u7c7b<\/li><li>\u5229\u7528\u6a21\u677f<br>\u7f3a\u70b9\u662f\u6a21\u677f\u5b9e\u4f8b\u5316\u7684\u65f6\u5019\u59cb\u7ec8\u5f97\u6307\u5b9a\u4e00\u4e2a\u57fa\u672c\u7c7b\u578b\uff0c\u76f8\u5f53\u4e8e\u8fd8\u662f\u5f97\u8bbe\u8ba1\u4e2a\u57fa\u7c7b<\/li><li>\u901a\u8fc7\u67d0\u79cd\u7c7b\u578b\u5bb9\u5668\u6765\u64e6\u9664\u7c7b\u578b<br>\u5c31\u662f\u4f7f\u7528variant\uff0c\u7f3a\u70b9\u662f\u8981\u4e00\u5f00\u59cb\u6307\u5b9a\u6240\u6709\u5c06\u8981\u5305\u542b\u7684\u7c7b\u578b<\/li><li>\u901a\u8fc7\u67d0\u79cd\u901a\u7528\u7c7b\u578b\u6765\u64e6\u9664<br>\u5c31\u662f\u4f7f\u7528any<\/li><li>\u901a\u8fc7\u95ed\u5305\u6765\u64e6\u9664\u7c7b\u578b<br>\u4f5c\u8005\u4e3e\u4e86\u4e0b\u9762\u8fd9\u6837\u4e00\u6bb5\u793a\u4f8b\u4ee3\u7801\uff0c\u53ef\u4ee5\u770b\u51fa\u5e76\u6ca1\u6709\u5173\u4e8e\u7c7b\u578b\u7684\u786c\u7f16\u7801\uff1a<\/li><\/ol>\n\n\n\n<pre class=\"wp-block-code\"><code>   template&lt;typename T&gt;\n   void Func(T t)\n   {\n     cout &lt;&lt; t &lt;&lt; endl;\n   }\n   void TestErase()\n   {\n     int x = 1;\n     char y = 's';\n\n     vector&lt;std::function&lt;void()&gt;&gt; v;\n     \/\/\u7c7b\u578b\u64e6\u9664\uff0c\u95ed\u5305\u4e2d\u9690\u85cf\u4e86\u5177\u4f53\u7684\u7c7b\u578b\uff0c\u5c06\u95ed\u5305\u4fdd\u5b58\u8d77\u6765\n     v.push_back(&#91;x]{Func(x);});\n     v.push_back(&#91;y]{Func(y);});\n     \/\/\u904d\u5386\u95ed\u5305\uff0c\u4ece\u95ed\u5305\u4e2d\u53d6\u51fa\u5b9e\u9645\u7684\u53c2\u6570\uff0c\u5e76\u6253\u5370\u51fa\u6765\n     for (auto item : v)\n     {\n       item();\n     }\n   }<\/code><\/pre>\n\n\n\n<p>\u4f5c\u8005\u9009\u7528\u4e86any\u548c\u95ed\u5305\u6765\u5b9e\u73b0\u4e00\u4e2a\u8fd9\u6837\u7684\u5de5\u5382\uff0c\u601d\u8def\u5c31\u662f\u5728\u5de5\u5382\u5185\u90e8\u521b\u5efa\u4e00\u4e2astring\u5230any\u7684map\uff0cstring\u7528\u6765\u4f5c\u4e3akey\u6307\u660e\u8981\u91c7\u7528\u4ec0\u4e48\u6837\u7684\u6784\u9020\u51fd\u6570\u6765\u521b\u5efa\u5bf9\u8c61\uff0cany\u5219\u4fdd\u5b58\u76f8\u5bf9\u5e94\u7684\u6784\u9020\u51fd\u6570\u7684\u95ed\u5305\u3002\u4e3a\u4e86\u80fd\u591f\u652f\u6301\u5e26\u53c2\u6570\u7684\u6784\u9020\u51fd\u6570\uff0c\u4f5c\u8005\u53c8\u5229\u7528\u4e86\u53ef\u53d8\u6a21\u677f\u53c2\u6570\u7684\u7279\u6027\uff0c\u5c06\u65e0\u53c2\u6784\u9020\u51fd\u6570\u548c\u5e26\u53c2\u6570\u7684\u6784\u9020\u51fd\u6570\u5f62\u5f0f\u4e0a\u7edf\u4e00\u4e86\u8d77\u6765\u3002\u6700\u540e\u4f5c\u8005\u8fd8\u5229\u7528<code>enable_if<\/code>\u5b9e\u73b0\u4e86\u5bf9\u4e8e\u6ca1\u6709\u7ee7\u627f\u5173\u7cfb\u7684\u4e24\u4e2a\u7c7b\u578b\u521b\u5efa\u4f9d\u8d56\u5bf9\u8c61\uff0c\u800c\u5bf9\u4e8e\u6709\u7ee7\u627f\u5173\u7cfb\u7684\u4e24\u4e2a\u7c7b\u578b\u521b\u5efa\u6d3e\u751f\u7c7b\u7684\u5bf9\u8c61\u3002<\/p>\n\n\n\n<p>\u672c\u7ae0\u4f5c\u8005\u7684<a href=\"https:\/\/github.com\/qicosmos\/cosmos\/blob\/master\/Ioc.hpp\">\u4ee3\u7801\u5b9e\u73b0<\/a>\uff0c\u4e0d\u8fc7\u6ca1\u6709<code>enable_if<\/code>\u7684\u7248\u672c\uff0c\u8fd9\u4e2a\u53ea\u6709\u770b\u4e66\u4e0a\u7684\u5b9e\u73b0\u4e86\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4f7f\u7528C++11\u5f00\u53d1\u4e00\u4e2a\u8f7b\u91cf\u7ea7\u7684IoC\u5bb9\u5668 \u5728\u5de5\u4f5c\u4e2d\u9047\u5230\u4e00\u4e2a\u4e0eIoC\u5bb9\u5668\u7c7b\u4f3c\u7684\u95ee\u9898\uff0c\u90a3\u5c31\u662f\u4e0d\u540c\u7ebf\u7a0b\u4e4b\u95f4\u901a\u4fe1\u7684\u65f6\u5019\u60f3\u901a\u8fc7\u540c\u4e00\u4e2a\u961f\u5217\u4f20\u9012\u4e0d\u540c\u7c7b\u578b\u7684\u6570\u636e\uff0c\u800c\u8fd9\u4e9b\u6570\u636e\u7684\u7c7b\u578b\u5e76\u6ca1\u6709\u7ee7\u627f\u5173\u7cfb\uff0c\u4e0d\u5c5e\u4e8e\u540c\u4e00\u4e2a\u57fa\u7c7b\u7684\u5b50\u7c7b&#46;&#46;&#46;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[8,7,9],"class_list":["post-47","post","type-post","status-publish","format-standard","hentry","category-10","tag-c","tag-c11","tag-9"],"_links":{"self":[{"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=\/wp\/v2\/posts\/47","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=47"}],"version-history":[{"count":1,"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=\/wp\/v2\/posts\/47\/revisions"}],"predecessor-version":[{"id":48,"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=\/wp\/v2\/posts\/47\/revisions\/48"}],"wp:attachment":[{"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=47"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=47"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.cauchyschwarz.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=47"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}