cppreference.com 创建账户 页面 讨论 变换 查看 编辑 历史 std::type_infoC++ 工具库 类型支持 std::type_info 在标头 <typeinfo> 定义 class type_info; 类type_info 保有有关一个类型的实现特定信息,包括该类型的名称和比较两个类型的相等性或校排顺序的方法。这是 typeid 运算符所返回的类。
cppreference.com 创建账户 页面 讨论 变换 查看 编辑 历史 std::type_info::beforeC++ 工具库 类型支持 std::type_info bool before( const type_info& rhs ) const; (C++11 起为 noexcept) 若此type_info 的类型在实现的对照顺序中列于 rhs 的类型之前则返回 true。不给出保证,特别是对照顺序可以在...
cppreference.com Create account Page Discussion Standard revision:DiffC++98/03C++11C++14C++17C++20C++23C++26 View Edit History std::type_info::before C++ Utilities library Type support std::type_info boolbefore(consttype_info&rhs)const;
Run this code #include <iostream>#include <typeinfo>structBase{virtual~Base()=default;};structDerived:Base{};intmain(){Base b1;Derived d1;constBase*pb=&b1;std::cout<<typeid(*pb).name()<<'\n';pb=&d1;std::cout<<typeid(*pb).name()<<'\n';} ...
我正在尝试初始化一个元组(使用std::make_tuple),我也想在其中存储一个std::type_info,但是我不知道为什么由于某种原因这段简单的代码无法编译。 我试着运行以下代码: javascript 运行次数:0 AI代码解释 #include<iostream>#include<string>#include<tuple>#include<typeinfo>#include<any>intmain(){std::tuple<...
When compiling an project on windows using the MSVC standard library I get an ambiguous reference to type_info: I have attached an archive of the most simple repro of the issue. It also includes the ii file from save-temps. Error Message: In file included from main.cpp:1: In file inclu...
I'd like to have more generic mechanism but I'm not sure we should rely on gcc/clang implementation of typeid on libpmemobj-cpp level. This would mean we have to check for pool compatibility even in cases where users do not wish to use type numbers. Maybe the best way would be to ...
#include <iostream>#include <typeinfo>#include <unordered_map>#include <string>#include <functional>#include <memory>structA{virtual~A(){}};structB:A{};structC:A{};usingTypeInfoRef=std::reference_wrapper<conststd::type_info>;structHasher{std::size_toperator()(TypeInfoRef code)const{retur...
cppreference.com Create account Page Discussion Standard revision:DiffC++98/03C++11C++14C++17C++20C++23C++26 View Edit History std::type_info C++ Utilities library Type support std::type_info Defined in header<typeinfo> classtype_info;
cppreference.com 创建账户 页面 讨论 变换 查看 编辑 历史 std::type_info::hash_codeC++ 工具库 类型支持 std::type_info std::size_t hash_code() const noexcept; (C++11 起) 返回未指定值(此处成为散列码),使得所有指代同一类型的 std::type_info 对象的散列码都相同。 不给出其他保证:指代不同...