Why is `std::make_unique` Missing in C 11, and How Does Perfect Forwarding Work in its Implementation?

Make_unique and Perfect Forwarding

Q: Why is the centralized make_unique function missing in the C 11 standard library?

Many find the construction boilerplate for unique pointers inconvenient. For example:

std::unique_ptr<SomeUserDefinedType> p(new SomeUserDefinedType(1, 2, 3));

A sleek function like this would be preferred:

auto p = std::make_unique<SomeUserDefinedType>(1, 2, 3);

Q: Here's a make_unique implementation attempt, but something about the std::forward appears broken. What is it doing and how is it supposed to be used?

template<typename T, typename... Args>
std::unique_ptr<T> make_unique(Args&&... args)
{
    return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
}

A: The omission of std::make_unique in C 11 was acknowledged as an oversight: it was added in C 14.

The std::forward(args) expression employs perfect forwarding to produce an artificial reference to the arguments ...args, allowing them to be forwarded to the new expression in T(std::forward(args)...) and unify the construction behavior for lvalues and rvalues.

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