Why is `std::make_unique` a valuable addition to C despite its complexity?

std::make_unique: A Missing Standard Library Convenience

The C 11 standard library lacks a std::make_unique function template, leaving developers to write verbose code to create unique pointers. Consider the following example:

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

To alleviate this verbosity, some developers have proposed a make_unique function:

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

This syntax hides the new operator and mentions the type only once.

However, implementing such a function requires understanding the intricacies of perfect forwarding. Specifically, the std::forward expression:

std::forward<Args>(args)...

involves the following operations:

• std::forward is a type transformation expression that forwards any lvalue or rvalue references of Args to the result.
• std::forward(args) is a function call expression that deduces and constructs Args by forwarding the corresponding arguments in args.
• ... unpacks the forwarded arguments into a parameter pack.

In summary, std::forward<Args>(args)... allows perfect forwarding of arguments to constructors.

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