How does Ansible implement configuration management — through a declarative or imperative style?

The using directive in C++ is used to simplify access to names from namespaces or to create type aliases.

Main cases of use:

1. Importing names from a namespace:

using namespace std; // allows using names from std without the std:: prefix

2. Importing a specific name:

using std::cout; // now you can write cout instead of std::cout

3. Creating type aliases:

using IntVector = std::vector<int>; // alias for a type

The using directive makes code easier to read and write, reducing the need to write long qualified names.