{"id":7552,"date":"2026-07-31T23:08:54","date_gmt":"2026-07-31T15:08:54","guid":{"rendered":"https:\/\/i007.cc\/wordpress\/?p=7552"},"modified":"2026-07-31T23:08:54","modified_gmt":"2026-07-31T15:08:54","slug":"%e8%ae%b2%e8%ae%b2-effective-modern-c-%e9%87%8c%e9%9d%a2%e7%9a%84%e9%87%8d%e7%82%b9%e7%ab%a0%e8%8a%82","status":"publish","type":"post","link":"https:\/\/i007.cc\/wordpress\/archives\/7552","title":{"rendered":"\u8bb2\u8bb2 Effective Modern C++ \u91cc\u9762\u7684\u91cd\u70b9\u7ae0\u8282"},"content":{"rendered":"
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\u8fd9\u672c\u4e66\u662f Senior C++ \u5de5\u7a0b\u5e08\u7684\u5fc5\u8bfb\u6e05\u5355\uff0cScott Meyers \u628a C++11\/14 \u91cc\u6700\u5bb9\u6613\u8e29\u5751\u7684\u5730\u65b9\u7cfb\u7edf\u68b3\u7406\u4e86\u4e00\u904d\u3002\u9488\u5bf9\u4f60\u7684\u60c5\u51b5\uff0c\u6309\u91cd\u8981\u7a0b\u5ea6\u548c\u9762\u8bd5\u9891\u7387\u8fc7\u4e00\u904d\u6838\u5fc3\u7ae0\u8282\u3002<\/p>\n

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\u7b2c\u4e94\u7ae0\uff1a\u53f3\u503c\u5f15\u7528\u3001\u79fb\u52a8\u8bed\u4e49\u3001\u5b8c\u7f8e\u8f6c\u53d1\uff08\u6700\u91cd\u8981\uff09<\/h3>\n

\u8fd9\u7ae0\u662f\u5168\u4e66\u7cbe\u534e\uff0cNVIDIA \u9762\u8bd5\u5fc5\u95ee\u3002<\/p>\n

Item 23\uff1a\u7406\u89e3 std::move \u548c std::forward<\/h4>\n

std::move<\/code>\u00a0\u4e0d\u79fb\u52a8\u4efb\u4f55\u4e1c\u897f\uff0c\u5b83\u53ea\u662f\u4e00\u4e2a\u5f3a\u5236\u8f6c\u6362\u6210\u53f3\u503c\u5f15\u7528<\/strong>\u7684 cast\uff1a<\/p>\n

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\/\/ std::move \u7684\u771f\u5b9e\u5b9e\u73b0\r\ntemplate<typename T>\r\ndecltype(auto) move(T&& param) {\r\n    using ReturnType = std::remove_reference_t<T>&&;\r\n    return static_cast<ReturnType>(param);\r\n}\r\n\r\n\/\/ \u8fd9\u610f\u5473\u7740\uff1a\r\nstd::string s = \"hello\";\r\nstd::string s2 = std::move(s);  \/\/ s \u53d8\u6210\u53f3\u503c\uff0c\u89e6\u53d1\u79fb\u52a8\u6784\u9020\r\n\/\/ s \u73b0\u5728\u5904\u4e8e\"\u6709\u6548\u4f46\u672a\u6307\u5b9a\"\u72b6\u6001\uff0c\u4e0d\u8981\u518d\u4f7f\u7528 s \u7684\u503c\r\n\r\n\/\/ \u5e38\u91cf\u5bf9\u8c61 move \u6ca1\u6709\u610f\u4e49\uff01\r\nconst std::string cs = \"world\";\r\nstd::string s3 = std::move(cs);  \/\/ \u5b9e\u9645\u8c03\u7528\u7684\u662f\u62f7\u8d1d\u6784\u9020\uff01\r\n\/\/ const T&& \u65e0\u6cd5\u7ed1\u5b9a\u5230 T&& \u53c2\u6570\uff0c\u9000\u5316\u4e3a\u62f7\u8d1d<\/pre>\n
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std::forward<\/code>\u00a0\u662f\u6761\u4ef6\u8f6c\u6362<\/strong>\uff1a\u53ea\u6709\u5f53\u53c2\u6570\u7ed1\u5b9a\u7684\u662f\u53f3\u503c\u65f6\u624d\u8f6c\u6210\u53f3\u503c\uff1a<\/p>\n
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\/\/ \u5b8c\u7f8e\u8f6c\u53d1\uff1a\u4fdd\u6301\u539f\u59cb\u503c\u7c7b\u522b\u4f20\u9012\u7ed9\u76ee\u6807\u51fd\u6570\r\ntemplate<typename T>\r\nvoid wrapper(T&& arg) {\r\n    \/\/ \u4e0d\u52a0 forward\uff1aarg \u662f\u5de6\u503c\uff08\u6709\u540d\u5b57\u7684\u53d8\u91cf\u90fd\u662f\u5de6\u503c\uff09\r\n    target(arg);               \/\/ \u603b\u662f\u62f7\u8d1d\r\n\r\n    \/\/ \u52a0 forward\uff1a\u4fdd\u7559\u539f\u59cb\u7c7b\u578b\r\n    target(std::forward<T>(arg));  \/\/ \u5de6\u503c\u4f20\u5de6\u503c\uff0c\u53f3\u503c\u4f20\u53f3\u503c\r\n}<\/pre>\n
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Item 24\uff1a\u533a\u5206\u901a\u7528\u5f15\u7528\u4e0e\u53f3\u503c\u5f15\u7528<\/h4>\n
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\/\/ \u8fd9\u662f\u53f3\u503c\u5f15\u7528\uff0c\u53ea\u80fd\u7ed1\u5b9a\u53f3\u503c\r\nvoid f(Widget&& w);\r\n\r\n\/\/ \u8fd9\u662f\u901a\u7528\u5f15\u7528\uff08Universal Reference\uff09\uff1aT \u5fc5\u987b\u88ab\u63a8\u5bfc\r\ntemplate<typename T>\r\nvoid f(T&& param);     \/\/ \u53ef\u4ee5\u7ed1\u5b9a\u5de6\u503c\u4e5f\u53ef\u4ee5\u7ed1\u5b9a\u53f3\u503c\r\n\r\nauto&& x = expr;      \/\/ \u4e5f\u662f\u901a\u7528\u5f15\u7528\r\n\r\n\/\/ \u533a\u522b\u7684\u5173\u952e\uff1a\u6709\u6ca1\u6709\u7c7b\u578b\u63a8\u5bfc\r\nWidget&& r = w;       \/\/ \u53f3\u503c\u5f15\u7528\uff0cW \u5df2\u786e\u5b9a\uff0c\u4e0d\u63a8\u5bfc<\/pre>\n
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\u901a\u7528\u5f15\u7528\u80fd\u7ed1\u5b9a\u5de6\u503c\u65f6\uff0cT \u88ab\u63a8\u5bfc\u4e3a\u00a0T&<\/code>\uff0c\u5229\u7528\u5f15\u7528\u6298\u53e0\u89c4\u5219\u6700\u7ec8\u5f97\u5230\u5de6\u503c\u5f15\u7528\uff1a<\/p>\n
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\/\/ \u5f15\u7528\u6298\u53e0\u89c4\u5219\uff08Item 28\uff09\r\nT& &   \u2192 T&\r\nT& &&  \u2192 T&\r\nT&& &  \u2192 T&\r\nT&& && \u2192 T&&   \/\/ \u53ea\u6709\u8fd9\u4e00\u79cd\u60c5\u51b5\u6700\u7ec8\u662f\u53f3\u503c\u5f15\u7528<\/pre>\n
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Item 29\uff1a\u4e0d\u8981\u5047\u8bbe\u79fb\u52a8\u64cd\u4f5c\u53c8\u5feb\u53c8\u5ec9\u4ef7<\/h4>\n
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\/\/ \u8fd9\u4e9b\u60c5\u51b5 move \u4e0d\u6bd4 copy \u5feb\uff1a\r\n\r\n\/\/ 1. std::array\uff1a\u5143\u7d20\u5728\u6808\u4e0a\uff0cmove \u4ecd\u7136\u8981\u62f7\u8d1d\u6240\u6709\u5143\u7d20\r\nstd::array<int, 1000> a1;\r\nstd::array<int, 1000> a2 = std::move(a1);  \/\/ O(n) \uff01\r\n\r\n\/\/ 2. SSO\uff08Small String Optimization\uff09\uff1a\u77ed\u5b57\u7b26\u4e32\u5728\u6808\u5185\r\nstd::string short_str = \"hi\";\r\nstd::string s2 = std::move(short_str);  \/\/ \u53ef\u80fd\u4ecd\u7136\u62f7\u8d1d\r\n\r\n\/\/ 3. noexcept \u4e0d\u6ee1\u8db3\u65f6\uff0cvector \u6269\u5bb9\u7528 copy \u4e0d\u7528 move\r\nstruct MyType {\r\n    MyType(MyType&&);   \/\/ \u6ca1\u6709 noexcept\uff01\r\n};\r\n\/\/ vector<MyType> \u6269\u5bb9\u65f6\u4f1a\u7528\u62f7\u8d1d\u6784\u9020\u800c\u975e\u79fb\u52a8\u6784\u9020\uff0c\u56e0\u4e3a\u9700\u8981\u5f3a\u5f02\u5e38\u5b89\u5168<\/pre>\n
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\u6700\u4f73\u5b9e\u8df5<\/strong>\uff1a\u81ea\u5b9a\u4e49\u7c7b\u578b\u7684\u79fb\u52a8\u6784\u9020\/\u8d4b\u503c\u52a1\u5fc5\u52a0\u00a0noexcept<\/code>\uff1a<\/p>\n
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class Buffer {\r\n    char* data_;\r\n    size_t size_;\r\npublic:\r\n    Buffer(Buffer&& other) noexcept   \/\/ \u5fc5\u987b\u52a0 noexcept\r\n        : data_(other.data_), size_(other.size_) {\r\n        other.data_ = nullptr;\r\n        other.size_ = 0;\r\n    }\r\n    Buffer& operator=(Buffer&& other) noexcept { ... }\r\n};<\/pre>\n
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\u7b2c\u56db\u7ae0\uff1a\u667a\u80fd\u6307\u9488<\/h3>\n
Item 18\/19\/20\uff1a\u4e09\u79cd\u667a\u80fd\u6307\u9488\u7684\u9009\u62e9\u539f\u5219<\/h4>\n
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\/\/ unique_ptr\uff1a\u72ec\u5360\u6240\u6709\u6743\uff0c\u96f6\u5f00\u9500\uff08\u548c\u88f8\u6307\u9488\u4e00\u6837\u5927\uff09\r\n\/\/ \u6e38\u620f\u91cc\uff1a\u6e38\u620f\u5bf9\u8c61\u3001\u8d44\u6e90\u7684\u552f\u4e00\u6301\u6709\u8005\r\nauto player = std::make_unique<Player>(uid);\r\n\r\n\/\/ \u5de5\u5382\u51fd\u6570\u8fd4\u56de unique_ptr\uff0c\u8c03\u7528\u65b9\u53ef\u4ee5\u9009\u62e9\u8f6c\u6210 shared_ptr\r\nstd::unique_ptr<Shape> make_shape(ShapeType type) {\r\n    switch(type) {\r\n        case CIRCLE: return std::make_unique<Circle>();\r\n        default:     return nullptr;\r\n    }\r\n}\r\n\r\n\/\/ shared_ptr\uff1a\u5f15\u7528\u8ba1\u6570\u5171\u4eab\u6240\u6709\u6743\r\n\/\/ \u4ee3\u4ef7\uff1a\u63a7\u5236\u5757\u5728\u5806\u4e0a\uff0c\u5f15\u7528\u8ba1\u6570\u662f\u539f\u5b50\u64cd\u4f5c\uff08\u591a\u7ebf\u7a0b\u5f00\u9500\uff09\r\n\/\/ \u6e38\u620f\u91cc\u8c28\u614e\u4f7f\u7528\u2014\u2014\u9ad8\u9891\u521b\u5efa\/\u9500\u6bc1\u7684\u5bf9\u8c61\u4e0d\u8981\u7528 shared_ptr\r\nauto mesh = std::make_shared<Mesh>(\"player.fbx\");\r\n\r\n\/\/ weak_ptr\uff1a\u4e0d\u5f71\u54cd\u751f\u547d\u5468\u671f\u7684\u89c2\u5bdf\u8005\r\n\/\/ \u89e3\u51b3 shared_ptr \u5faa\u73af\u5f15\u7528\uff0c\u4ee5\u53ca\"\u6211\u60f3\u5f15\u7528\u4f46\u4e0d\u60f3\u5ef6\u957f\u751f\u547d\"\r\nstd::weak_ptr<Player> target_weak = enemy->target;  \/\/ AI \u7784\u51c6\u76ee\u6807\r\n\r\nvoid AI::update() {\r\n    auto target = target_weak.lock();  \/\/ \u5b89\u5168\u5730\u5c1d\u8bd5\u83b7\u53d6\r\n    if (!target) {\r\n        \/\/ \u76ee\u6807\u5df2\u6b7b\u4ea1\uff0c\u5207\u6362\u72b6\u6001\r\n        state_ = IDLE;\r\n        return;\r\n    }\r\n    move_towards(target->position());\r\n}<\/pre>\n
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Item 21\uff1a\u4f18\u5148\u7528 make_unique \/ make_shared<\/h4>\n
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\/\/ \u9519\u8bef\u5199\u6cd5\uff08\u5b58\u5728\u5f02\u5e38\u5b89\u5168\u6f0f\u6d1e\uff09\r\nprocess(std::shared_ptr<Widget>(new Widget), compute_priority());\r\n\/\/ \u7f16\u8bd1\u5668\u53ef\u80fd\u7684\u6267\u884c\u987a\u5e8f\uff1a\r\n\/\/ 1. new Widget\r\n\/\/ 2. compute_priority() \u2190 \u5982\u679c\u8fd9\u91cc\u629b\u5f02\u5e38\uff0cWidget \u6cc4\u6f0f\uff01\r\n\/\/ 3. \u6784\u9020 shared_ptr\r\n\r\n\/\/ \u6b63\u786e\u5199\u6cd5\r\nprocess(std::make_shared<Widget>(), compute_priority());\r\n\/\/ make_shared \u8fd8\u6709\u989d\u5916\u597d\u5904\uff1a\u628a\u5bf9\u8c61\u548c\u63a7\u5236\u5757\u5206\u914d\u5728\u4e00\u5757\u5185\u5b58\uff0c\u51cf\u5c11\u4e00\u6b21 new<\/pre>\n
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Item 22\uff1aPimpl \u60ef\u7528\u6cd5\u8981\u5728\u5b9e\u73b0\u6587\u4ef6\u91cc\u5b9a\u4e49\u6790\u6784\u51fd\u6570<\/h4>\n
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\/\/ Widget.h\r\nclass Widget {\r\n    struct Impl;\r\n    std::unique_ptr<Impl> pImpl_;  \/\/ \u4e0d\u5b8c\u6574\u7c7b\u578b\r\npublic:\r\n    Widget();\r\n    ~Widget();  \/\/ \u53ea\u58f0\u660e\uff0c\u4e0d\u5728\u5934\u6587\u4ef6\u5b9a\u4e49\uff01\r\n};\r\n\r\n\/\/ Widget.cpp\r\nstruct Widget::Impl { ... };  \/\/ Impl \u5728\u8fd9\u91cc\u5b8c\u6574\u5b9a\u4e49\r\n\r\nWidget::Widget() : pImpl_(std::make_unique<Impl>()) {}\r\nWidget::~Widget() = default;  \/\/ \u5728 Impl \u5b8c\u6574\u5b9a\u4e49\u4e4b\u540e\u624d\u80fd default\r\n\/\/ \u5982\u679c\u5728\u5934\u6587\u4ef6 default\uff0cunique_ptr \u7684 deleter \u770b\u5230\u4e0d\u5b8c\u6574\u7c7b\u578b \u2192 \u7f16\u8bd1\u9519\u8bef<\/pre>\n
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Item 14\uff1anoexcept \u7684\u610f\u4e49\u8fdc\u8d85”\u8868\u793a\u4e0d\u629b\u5f02\u5e38”<\/h4>\n
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\/\/ noexcept \u662f\u63a5\u53e3\u7684\u4e00\u90e8\u5206\uff0c\u5f71\u54cd\u7f16\u8bd1\u5668\u4f18\u5316\r\n\r\n\/\/ \u6ca1\u6709 noexcept\uff1a\u7f16\u8bd1\u5668\u5fc5\u987b\u7ef4\u62a4\u6808\u5c55\u5f00\u4fe1\u606f\uff0c\u751f\u6210\u989d\u5916\u4ee3\u7801\r\nvoid f();\r\n\r\n\/\/ \u6709 noexcept\uff1a\u7f16\u8bd1\u5668\u53ef\u4ee5\u6fc0\u8fdb\u4f18\u5316\uff0c\u7701\u53bb exception table\r\nvoid g() noexcept;\r\n\r\n\/\/ \u6700\u91cd\u8981\u7684\u5f71\u54cd\uff1aSTL \u5bb9\u5668\u6269\u5bb9\u7b56\u7565\r\n\/\/ vector::push_back \u6269\u5bb9\u65f6\u9700\u8981\u642c\u79fb\u5143\u7d20\r\n\/\/ \u5982\u679c\u79fb\u52a8\u6784\u9020\u662f noexcept\uff0c\u7528 move\uff08O(1)\uff09\r\n\/\/ \u5982\u679c\u4e0d\u662f noexcept\uff0c\u7528 copy\uff08\u63d0\u4f9b\u5f3a\u5f02\u5e38\u5b89\u5168\u4fdd\u8bc1\uff09\r\n\r\n\/\/ \u5b9e\u9645\u539f\u5219\uff1a\u6790\u6784\u51fd\u6570\u3001swap\u3001\u79fb\u52a8\u6784\u9020\/\u8d4b\u503c\uff0c\u80fd noexcept \u5c31\u52a0<\/pre>\n
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Item 15\uff1aconstexpr \u7684\u6b63\u786e\u7406\u89e3<\/h4>\n
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\/\/ constexpr \u4e0d\u53ea\u662f\"\u7f16\u8bd1\u671f\u5e38\u91cf\"\uff0c\u5b83\u662f\"\u5982\u679c\u53ef\u4ee5\u5c31\u5728\u7f16\u8bd1\u671f\uff0c\u5426\u5219\u5728\u8fd0\u884c\u671f\"\r\n\r\nconstexpr int factorial(int n) {\r\n    return n <= 1 ? 1 : n * factorial(n - 1);\r\n}\r\n\r\nconstexpr int f6 = factorial(6);   \/\/ \u7f16\u8bd1\u671f\u8ba1\u7b97\uff0c\u7ed3\u679c\u76f4\u63a5\u5d4c\u5165\u4e8c\u8fdb\u5236\r\nint runtime_n = get_from_user();\r\nint fn = factorial(runtime_n);      \/\/ \u8fd0\u884c\u671f\u8ba1\u7b97\uff0c\u666e\u901a\u51fd\u6570\u8c03\u7528\r\n\r\n\/\/ \u6e38\u620f\u91cc\u5e38\u89c1\u7528\u6cd5\uff1a\u7f16\u8bd1\u671f\u8ba1\u7b97 hash\u3001buffer size\u3001\u4f4d\u63a9\u7801\r\nconstexpr uint32_t hash_str(const char* s, size_t len) { ... }\r\nconstexpr uint32_t PLAYER_TAG = hash_str(\"player\", 6);<\/pre>\n
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Item 17\uff1a\u7279\u6b8a\u6210\u5458\u51fd\u6570\u7684\u81ea\u52a8\u751f\u6210\u89c4\u5219<\/h4>\n
\u8fd9\u662f\u5f88\u591a bug \u7684\u6765\u6e90\uff0c\u5fc5\u987b\u70c2\u719f\u4e8e\u5fc3\uff1a<\/p>\n
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cpp<\/div>\n
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\/\/ \u53ea\u8981\u4f60\u58f0\u660e\u4e86\u4efb\u4f55\u4e00\u4e2a\uff0c\u7f16\u8bd1\u5668\u7684\u81ea\u52a8\u751f\u6210\u884c\u4e3a\u5c31\u4f1a\u6539\u53d8\r\n\r\nclass MyClass {\r\n    \/\/ \u58f0\u660e\u4e86\u6790\u6784\u51fd\u6570 \u2192\r\n    \/\/   \u62f7\u8d1d\u6784\u9020\/\u8d4b\u503c\uff1a\u4ecd\u7136\u751f\u6210\uff08deprecated \u884c\u4e3a\uff0c\u4e0d\u8981\u4f9d\u8d56\uff09\r\n    \/\/   \u79fb\u52a8\u6784\u9020\/\u8d4b\u503c\uff1a\u4e0d\u518d\u81ea\u52a8\u751f\u6210\uff01\r\n\r\n    \/\/ \u58f0\u660e\u4e86\u79fb\u52a8\u6784\u9020 \u2192\r\n    \/\/   \u79fb\u52a8\u8d4b\u503c\uff1a\u4e0d\u81ea\u52a8\u751f\u6210\r\n    \/\/   \u62f7\u8d1d\u6784\u9020\/\u8d4b\u503c\uff1a\u88ab delete\r\n\r\n    \/\/ Rule of Five\uff1a\u8981\u4e48\u90fd\u4e0d\u58f0\u660e\uff0c\u8981\u4e48\u4e94\u4e2a\u90fd\u5199\r\n    ~MyClass();\r\n    MyClass(const MyClass&);\r\n    MyClass& operator=(const MyClass&);\r\n    MyClass(MyClass&&) noexcept;\r\n    MyClass& operator=(MyClass&&) noexcept;\r\n};\r\n\r\n\/\/ \u6700\u5e38\u89c1\u7684\u5751\uff1a\r\nclass Buffer {\r\n    char* data_;\r\npublic:\r\n    ~Buffer() { delete[] data_; }  \/\/ \u58f0\u660e\u4e86\u6790\u6784\u51fd\u6570\r\n    \/\/ \u79fb\u52a8\u6784\u9020\u6ca1\u6709\u81ea\u52a8\u751f\u6210\uff01\r\n    \/\/ vector<Buffer> \u6269\u5bb9\u65f6\u4f1a\u8c03\u7528\u62f7\u8d1d\u6784\u9020\uff0c\u6d45\u62f7\u8d1d data_ \u5bfc\u81f4 double free\r\n};<\/pre>\n
 <\/p>\n<\/div>\n<\/div>\n
\n
\u7b2c\u516d\u7ae0\uff1aLambda<\/h3>\n
Item 31\uff1a\u4e0d\u8981\u7528\u9ed8\u8ba4\u6355\u83b7<\/h4>\n
\n
\n
<\/div>\n<\/div>\n
cpp<\/div>\n
\n
\/\/ \u9ed8\u8ba4\u5f15\u7528\u6355\u83b7 [&]\uff1a\u5bb9\u6613\u60ac\u7a7a\u5f15\u7528\r\nauto create_adder(int x) {\r\n    return [&]() { return x + 1; };  \/\/ x \u662f\u5c40\u90e8\u53d8\u91cf\uff0clambda \u9003\u9038\u540e\u60ac\u7a7a\uff01\r\n}\r\n\r\n\/\/ \u9ed8\u8ba4\u503c\u6355\u83b7 [=]\uff1a\u770b\u8d77\u6765\u5b89\u5168\uff0c\u5b9e\u9645\u6697\u85cf\u9677\u9631\r\nclass Widget {\r\n    int value_ = 42;\r\n    auto create_lambda() {\r\n        return [=]() { return value_; };  \/\/ \u6355\u83b7\u7684\u662f this\uff0c\u4e0d\u662f value_\uff01\r\n        \/\/ \u7b49\u4ef7\u4e8e [this]() { return this->value_; }\r\n        \/\/ Widget \u6790\u6784\u540e\uff0clambda \u518d\u8c03\u7528 \u2192 UB\r\n    }\r\n};\r\n\r\n\/\/ \u6b63\u786e\u5199\u6cd5\uff1a\u660e\u786e\u6355\u83b7\r\nauto create_lambda() {\r\n    int v = value_;\r\n    return [v]() { return v; };   \/\/ \u6355\u83b7\u503c\u7684\u526f\u672c\uff0c\u5b89\u5168\r\n}<\/pre>\n
 <\/p>\n<\/div>\n<\/div>\n
Item 32\uff1a\u7528\u521d\u59cb\u5316\u6355\u83b7\u79fb\u52a8\u5bf9\u8c61\u8fdb lambda<\/h4>\n
\n
\n
<\/div>\n<\/div>\n
cpp<\/div>\n
\n
\/\/ C++14 \u5f15\u5165\uff0c\u89e3\u51b3\"\u6211\u60f3\u628a\u4e00\u4e2a\u53ea\u80fd\u79fb\u52a8\u7684\u5bf9\u8c61\u653e\u8fdb lambda\"\u7684\u95ee\u9898\r\nauto upw = std::make_unique<Widget>();\r\n\r\n\/\/ C++14 init capture\r\nauto func = [w = std::move(upw)]() {\r\n    w->do_something();\r\n};\r\n\/\/ upw \u88ab\u79fb\u52a8\u8fdb\u4e86 lambda\uff0clambda \u5916\u90e8 upw \u53d8\u4e3a nullptr<\/pre>\n
 <\/p>\n<\/div>\n<\/div>\n
\n
\u7b2c\u4e03\u7ae0\uff1a\u5e76\u53d1 API<\/h3>\n
Item 40\uff1aatomic \u7528\u4e8e\u5e76\u53d1\uff0cvolatile \u7528\u4e8e\u7279\u6b8a\u5185\u5b58<\/h4>\n
\u8fd9\u662f\u6700\u5bb9\u6613\u6df7\u6dc6\u7684\u4e24\u4e2a\u5173\u952e\u5b57\uff1a<\/p>\n
\n
\n
<\/div>\n<\/div>\n
cpp<\/div>\n
\n
\/\/ std::atomic\uff1a\u591a\u7ebf\u7a0b\u53ef\u89c1\uff0c\u7f16\u8bd1\u5668\/CPU \u4e0d\u4f1a\u91cd\u6392\u76f8\u5173\u64cd\u4f5c\r\nstd::atomic<int> counter{0};\r\ncounter++;                    \/\/ \u539f\u5b50\u9012\u589e\uff0c\u7ebf\u7a0b\u5b89\u5168\r\ncounter.load(std::memory_order_acquire);   \/\/ \u5e26 memory order \u63a7\u5236\r\n\r\n\/\/ volatile\uff1a\u544a\u8bc9\u7f16\u8bd1\u5668\"\u4e0d\u8981\u4f18\u5316\u8fd9\u4e2a\u53d8\u91cf\u7684\u8bfb\u5199\"\r\n\/\/ \u7528\u9014\uff1a\u5185\u5b58\u6620\u5c04 IO\u3001\u4fe1\u53f7\u5904\u7406\u5668\u4fee\u6539\u7684\u53d8\u91cf\r\nvolatile int* hardware_register = (int*)0xDEADBEEF;\r\n*hardware_register = 1;  \/\/ \u7f16\u8bd1\u5668\u4e0d\u4f1a\u628a\u8fd9\u4e2a\u5199\u5165\u4f18\u5316\u6389\r\n\r\n\/\/ volatile \u4e0d\u662f\u7ebf\u7a0b\u5b89\u5168\u7684\uff01\r\n\/\/ std::atomic \u624d\u662f\u7ebf\u7a0b\u5b89\u5168\u7684\uff01\r\n\/\/ \u4e24\u8005\u5b8c\u5168\u4e0d\u540c\uff0c\u4e0d\u8981\u6df7\u7528\r\n\r\n\/\/ \u6e38\u620f\u91cc\u5e38\u89c1\u9519\u8bef\uff1a\r\nvolatile bool game_running = true;   \/\/ \u9519\u8bef\uff01\u7528 atomic\r\nstd::atomic<bool> game_running{true}; \/\/ \u6b63\u786e<\/pre>\n
 <\/p>\n<\/div>\n<\/div>\n
Item 35\uff1a\u4f18\u5148\u7528 std::async \u800c\u975e\u76f4\u63a5 std::thread<\/h4>\n
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cpp<\/div>\n
\n
\/\/ thread-based\uff1a\u81ea\u5df1\u7ba1\u7406\u7ebf\u7a0b\u751f\u547d\u5468\u671f\uff0c\u5bb9\u6613\u51fa\u9519\r\nint do_work();\r\nstd::thread t(do_work);   \/\/ \u5982\u679c do_work \u629b\u5f02\u5e38\uff0cthread \u6790\u6784\u65f6 terminate()\r\nt.join();\r\n\r\n\/\/ task-based\uff1a\u66f4\u5b89\u5168\uff0c\u8fd4\u56de future \u53ef\u4ee5\u62ff\u7ed3\u679c\/\u5f02\u5e38\r\nauto fut = std::async(std::launch::async, do_work);\r\n\/\/ \u5f02\u5e38\u4f1a\u88ab\u4f20\u64ad\u5230 future.get() \u5904\uff0c\u4e0d\u4f1a terminate\r\nint result = fut.get();   \/\/ \u5f02\u5e38\u5728\u8fd9\u91cc\u91cd\u65b0\u629b\u51fa\uff0c\u53ef\u4ee5 try-catch<\/pre>\n
 <\/p>\n<\/div>\n<\/div>\n
\n
\u9762\u8bd5\u91cc\u600e\u4e48\u7528\u8fd9\u4e9b\u77e5\u8bc6<\/h3>\n
NVIDIA \u6700\u559c\u6b22\u8003\u7684\u51e0\u4e2a\u7ec4\u5408\uff1a<\/p>\n
“\u89e3\u91ca move semantics”<\/strong>\u00a0\u2192 Item 23\/24\/29\uff0c\u8bf4 move \u662f cast \u4e0d\u662f\u64cd\u4f5c\uff0c\u8bf4 noexcept \u5bf9 vector \u6269\u5bb9\u7684\u5f71\u54cd\uff0c\u8bf4 const \u5bf9\u8c61 move \u9000\u5316\u4e3a copy\u3002<\/p>\n
“shared_ptr \u548c unique_ptr \u600e\u4e48\u9009”<\/strong>\u00a0\u2192 Item 18\/19\uff0c\u8bf4\u63a7\u5236\u5757\u7684\u5185\u5b58\u5f00\u9500\u548c\u539f\u5b50\u5f15\u7528\u8ba1\u6570\uff0c\u6e38\u620f\u9ad8\u9891\u5bf9\u8c61\u7528 unique_ptr \u6216\u5bf9\u8c61\u6c60\u3002<\/p>\n
“volatile \u548c atomic \u533a\u522b”<\/strong>\u00a0\u2192 Item 40\uff0c\u8fd9\u9053\u9898\u7b54\u5bf9\u7684\u4eba\u4e0d\u591a\uff0c\u7b54\u51fa\u6765\u7acb\u523b\u52a0\u5206\u3002<\/p>\n
“\u4f60\u5199\u8fc7 RAII \u5417”<\/strong>\u00a0\u2192 Item 15\/17\uff0c\u7ed3\u5408\u6790\u6784\u51fd\u6570\u4fdd\u8bc1\u8d44\u6e90\u91ca\u653e\uff0cRule of Five\uff0c\u79fb\u52a8\u8bed\u4e49\u3002<\/p>\n
\u4f60\u770b\u8fd9\u672c\u4e66\u7684\u65f6\u5019\uff0c\u5efa\u8bae\u628a\u6bcf\u4e2a Item \u914d\u4e00\u4e2a\u4f60\u5728\u6e38\u620f\u9879\u76ee\u91cc\u9047\u5230\u8fc7\u7684\u5b9e\u9645\u6848\u4f8b\uff0c\u9762\u8bd5\u65f6\u7528\u771f\u5b9e\u573a\u666f\u6765\u89e3\u91ca\u6bd4\u7eaf\u7cb9\u80cc\u4e66\u66f4\u6709\u8bf4\u670d\u529b\u3002<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"
\u8fd9\u672c\u4e66\u662f Senior C++ \u5de5\u7a0b\u5e08\u7684<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"colormag_page_container_layout":"default_layout","colormag_page_sidebar_layout":"default_layout","footnotes":""},"categories":[24],"tags":[],"class_list":["post-7552","post","type-post","status-publish","format-standard","hentry","category-value_docs"],"_links":{"self":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/7552","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/comments?post=7552"}],"version-history":[{"count":0,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/posts\/7552\/revisions"}],"wp:attachment":[{"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/media?parent=7552"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/categories?post=7552"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/i007.cc\/wordpress\/wp-json\/wp\/v2\/tags?post=7552"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}