With regard to the rvalue vs perfect forwarding references comment: there's actually no special syntactic difference between the two. The reason forwarding work

With regard to the rvalue vs perfect forwarding references comment: there's actually no special syntactic difference between the two. The reason forwarding works is because in template <typename T> void do_thing(T&&) T will (with an rvalue) match the actual type, whereas with an lvalue it will match a reference to the type (i.e., you're moving a reference). This is what allows something like std::forward to be in the standard library and implemented in the language itself (without accessing any compiler builtins). That's not to say what's going on there is obvious nor really easy to reason about. It's more a hack that happens to work, like much of the templating ecosystem.