I am coding functions like the well known tuple_apply, which take a rvalue reference of a Function as parameter. During my researches on the web, I came across the two following calls:

template <
    typename Func,
    /* stuff */
>
void myfunction(Func && func, /* stuff */)
{
    std::forward<Func>(func)(/* stuff */); // use of std::forward before call
    func(/* stuff */);                     // direct call
}

Is this call to std::forward really usefull ? If so why ?

Thanks for your enlightenment!