modern-cpp-tutorial/code/3/3.7.perfect.forward.cpp

//
// 3.6.perfect.forward.cpp
// modern c++ tutorial
//
// created by changkun at changkun.de
// https://github.com/changkun/modern-cpp-tutorial
//

#include <iostream>
#include <utility>
void reference(int& v) {
    std::cout << "lvalue reference" << std::endl;
}
void reference(int&& v) {
    std::cout << "rvalue reference" << std::endl;
}
template <typename T>
void pass(T&& v) {
    std::cout << "          normal param passing: ";
    reference(v);
    std::cout << "       std::move param passing: ";
    reference(std::move(v));
    std::cout << "    std::forward param passing: ";
    reference(std::forward<T>(v));
    std::cout << "static_cast<T&&> param passing: ";
    reference(static_cast<T&&>(v));
}
int main() {
    std::cout << "rvalue pass:" << std::endl;
    pass(1);
    
    std::cout << "lvalue pass:" << std::endl;
    int l = 1;
    pass(l);
    
    return 0;
}