template<classT>structadd_lvalue_reference;template<classT>usingadd_lvalue_reference_t=typenameadd_lvalue_reference<T>::type; 参数 T 要修改的类型。 注解 如果T为 lvalue 引用,则类型修饰符的实例将保持修改后的类型 T,否则为T&。 示例 C++
extern：声明一个变量，extern 声明的变量没有建立存储空间 const：定义一个常量，常量的值不能修改 ...
#include <type_traits> using non_ref = int; static_assert(std::is_lvalue_reference_v<non_ref> == false); using l_ref = std::add_lvalue_reference_t<non_ref>; static_assert(std::is_lvalue_reference_v<l_ref> == true); using r_ref = std::add_rvalue_reference_t<non_ref>; sta...
=typenameadd_lvalue_reference::type;usingrref =typenameadd_rvalue_reference::type;cout<<std::boolalpha;// Check if the above declaration// are correct or notcout<<"is int is lvalue? "<< is_lvalue_reference::value <<'\n';cout<<"is lref is lvalue? "<< is_lvalue_reference<lref>::...
add_lvalue_reference有什么作用? 我有这个类为montecarlo模拟器创建一个路径,它从一个可用的int数组创建整数路径。因此,例如,我们可以从包含{0,1,2,3,4}的数组中获得长度为3的路径,这将例如生成3,1,2和1,4,0。 //This path generator just generates a list of ints for each path...
如果T 为lvalue 引用,则类型修饰符的实例将保持修改后的类型 T,否则为 T&。示例C++ 复制 #include <type_traits> #include <iostream> using namespace std; int main() { int val = 0; add_lvalue_reference_t<int> p = (int&)val; p = p; // to quiet "unused" warning cout << "add_...
add_cv class add_lvalue_reference class add_rvalue_reference class add_pointer class add_volatile class aligned_storage class aligned_union class alignment_of class common_type class conditional class decay class enable_if class extent class integer_sequence class integral_constant class, bool_constant...
add_cv class add_lvalue_reference class add_rvalue_reference class add_pointer class add_volatile class aligned_storage class aligned_union class alignment_of class common_type class conditional class decay class enable_if class extent class integer_sequence class integral_constant class, bool_constant...
#include <type_traits> #include <iostream> using namespace std; int main() { int val = 0; add_lvalue_reference_t<int> p = (int&)val; p = p; // to quiet "unused" warning cout << "add_lvalue_reference_t<int> == " << typeid(p).name() << endl; return (0); } Output ...
#include <type_traits> #include <iostream> using namespace std; int main() { int val = 0; add_lvalue_reference_t<int> p = (int&)val; p = p; // to quiet "unused" warning cout << "add_lvalue_reference_t<int> == " << typeid(p).name() << endl; return (0); } Output ...