Quick A: the result is the same as calling the function you're forwarding to directly.

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Concise explanation of reference collapsing rules requested: (1) A& & -> A& , (2) A& && -> A& , (3) A&& & -> A& , and (4) A&& && -> A&&

The reference collapsing rules (save for A& & -> A&, which is C++98/03) exist for one reason: to allow perfect forwarding to work...