example4_perfect_forwarding.cpp

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#include <utility>
#include <iostream>
#include <string>

template<typename T>
void printType(T&& t) {
    std::cout << "T is " << (std::is_lvalue_reference<T>::value ? "lvalue" : "rvalue") << std::endl;
}

template<typename T>
void perfectForward(T&& t) {
    std::cout << "Forwarding: ";
    printType(std::forward<T>(t));
}

int main() {
    int x = 10;
    const int cx = 20;

    std::cout << "Forwarding lvalue:" << std::endl;
    perfectForward(x);

    std::cout << "Forwarding const lvalue:" << std::endl;
    perfectForward(cx);

    std::cout << "Forwarding rvalue:" << std::endl;
    perfectForward(5);

    std::cout << "Forwarding string literal:" << std::endl;
    perfectForward("hello");

    return 0;
}