功能特性测试宏值标准功能特性 __cpp_lib_constexpr_typeinfo 202106L (C++23) std::type_info::operator== 的constexpr 示例运行此代码 #include <iostream> #include <string> #include <typeinfo> #include <utility> class person { public: explicit person(std::string n) : name_(std::move(n)...
type_info 类既不满足可复制构造 (CopyConstructible) 也不满足可复制赋值 (CopyAssignable) 。 成员函数 (构造函数) [弃置] 无默认或复制构造函数 (公开成员函数) (析构函数) [虚] 虚析构函数使 type_info 为多态类 (虚公开成员函数) operator= [弃置] 不能复制赋值 (公开成员函数) operato...
问boost::asio在std::type_info::operator==中触发sigsegvENasio包含errorcode参数的函数，不会抛出异常 可以尝试connect之后，判断错误码， boost::asio::error::already_connected 则表示已经连接 断开连接使用close，is_open不表示通断，close后需要open，connect自动打开 ...
warning: failed to compute relocation: IMAGE_REL_I386_REL32, Invalid data was encountered while parsing the file lld-link: error: duplicate symbol: std::type_info::operator==(std::type_info const&) const >>> defined at C:/tools/msys64/mingw32/include/c++/10.3.0/typeinfo:121 >>> obje...
std::type_info类可以在执行期间查询对象型别,但使用起来比较麻烦。为此定义了wrapper下面的代码出自 Loki库:总得来说是提供了std::type_info的所有成员函数;提供了value语义,即public copy构造函数和public assignment操作符;定义了 operator< 和 operator== 等...
std::type_info::hash_code std::type_info::name std::type_info::operator!= std::type_info::operators std::unary_function std::unary_negate std::uncaught_exception std::uncaught_exceptions std::undeclare_no_pointers std::undeclare_reachable std::underflow_error std::underlying_type std::unex...
std::type_info::before std::type_info::hash_code std::type_info::name std::type_info::operator!= std::type_info::operators std::unary_function std::unary_negate std::uncaught_exception std::uncaught_exceptions std::undeclare_no_pointers std::undeclare_reachable std::underflow_error std:...
#include <functional>#include <iostream>#include <memory>#include <string>#include <typeinfo>#include <unordered_map>structA{virtual~A(){}};structB:A{};structC:A{};usingTypeInfoRef=std::reference_wrapper<conststd::type_info>;structHasher{std::size_toperator()(TypeInfoRef code)const{retur...
/home/fab/Applications/NXP/S32DS_Power_v2017.R1/S32DS/e200_ewl2/EWL_C++/include/ewl_smart_pointers:1322: undefined reference to `std::type_info::operator==(std::type_info const&) const'makefile:70: recipe for target 'cpp_stl_Z7_0.elf' failedcollect2: error: ld returned 1 exit ...
= '*' && [Current thread is 1 (Thread 0x7fe8ecaef700 (LWP 5994))] (gdb) bt #0 0x00005598515613c7 in std::type_info::operator== (this=0x7fe8f20aa950 <std::_Sp_make_shared_tag::_S_ti()::__tag>, __arg=...) at /usr/include/c++/8.2.1/typeinfo:123 #1 0x0000559851567235...