What's the equivalent of std::is_const for references to const?

Question

Consider the code:

int const  x = 50;
int const& y = x;
cout << std::is_const::value << endl; // 1
cout << std::is_c         


        

Answer 1

Use remove_reference:

#include <string>
#include <iostream>
#include <type_traits>
using namespace std;

int main()
{
    int const  x = 50;
    int const& y = x;
    cout << std::is_const<std::remove_reference<decltype(x)>::type>::value << endl; // 1
    cout << std::is_const<std::remove_reference<decltype(y)>::type>::value << endl; // 1

    return 0;
}

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