Is there a cast (or standard function) with the opposite effect to `std::move`

Question

First off, this question is not a duplicate of Function dual to std::move? or of Does the inverse of std::move exist?. I am not asking about a mechanism to

Answer 1

The function provided below is a bad idea. Don't use it. It provides a very easy path towards dangling references. I'd consider the code that needs it faulty and act accordingly.

Still, I think this is an interesting exercise for some reason, so I can't help but show it.

Inside a function, the names of its arguments are lvalues, even if the arguments are rvalue references. You can use that property to return an argument as an lvalue reference.

template 
constexpr T& as_lvalue(T&& t) {
    return t;
};