c++ - push_back or emplace_back with std::make_unique -

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based on answers in these questions here, know preferred use c++14's std::make_unique emplace_back(new x) directly.

that said, preferred call

my_vector.push_back(std::make_unique<foo>("constructor", "args"));

or 

my_vector.emplace_back(std::make_unique<foo>("constructor", "args"));

that is, should use push_back or emplace_back when adding std::unique_ptr constructed std::make_unique?

==== edit ====

and why? c: <-- (tiny smile)

it doesn't make difference, have unique_ptr<foo> prvalue (the result of call make_unique) both push_back , emplace_back call unique_ptr move constructor when constructing element appended vector.


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