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Advantages of using forward
Could someone please explain to me what perfect forwarding is about?
http://www.justsoftwaresolutions.co.uk/cplusplus/rvalue_references_and_perfect_forwarding.html
Why is this useful? Well, it means that a function template can pass its arguments through to another function whilst retaining the lvalue/rvalue nature of the function arguments by using std::forward. This is called "perfect forwarding", avoids excessive copying, and avoids the template author having to write multiple overloads for lvalue and rvalue references.