小编Tes*_*est的帖子

Reference fluentCPP article

The below code explanation says that this structure inherits from several lambdas, can be constructed from those lambdas, and folds over the using expression.

template<typename... Lambdas>
struct overloaded : public Lambdas...
{
    explicit overloaded(Lambdas... lambdas) : Lambdas(lambdas)... {}

    using Lambdas::operator()...;
};

My doubt is that parentheses i.e () indicate a c++17 fold expression but I don't see any enclosing parentheses around the using statement. How will it fold?

在尝试重载 << 运算符时，我无法编译以下代码。任何人都可以指出出了什么问题吗？

#include <iostream>

std::ostream& operator<<(std::ostream& i, int n)
{
    return i;
}

int main()
{
    std::cout << 5 << std::endl;
    std::cin.get();
    return 0;
}