Is there a reference_wrapper<> for rvalue references?

Question

I wonder how the following can be done

void f(string &&s) { 
  std::string i(move(s)); 
  /* other stuff */ 
} 

int main() { 
  std::string s; 
  bi         


        

Answer 1

How can I pass an rvalue reference and store it as an rvalue reference in the call wrapper?

The problem here is that such a bind function object can be invoked multiple times. If the function object forwarded a bound parameter as rvalue this would obviously only work once. So, this is a bit of a safety issue.

But in some cases this kind of forwarding is exactly what you want. You could use a lambda as an intermediary:

bind([](string& s){f(move(s));},move(s));

Basically, I came up with this bind+lambda combination as a workaround for a missing "move-capture".