What is the name of the ability to call a function without explicitly specifying a namespace?

using declaration or using directive.

• using declaration: Allows using a specific name from a namespace without a prefix.

  namespace MyNamespace {
      void myFunction();
  }
  
  using MyNamespace::myFunction; // Declaration
  
  int main() {
      myFunction(); // Can be called directly
      return 0;
  }
  

• using directive: Allows access to all names in a namespace without needing to specify the prefix.

  namespace AnotherNamespace {
      void anotherFunction();
      int myVariable;
  }
  
  using namespace AnotherNamespace; // Directive
  
  int main() {
      anotherFunction(); // Can be called directly
      myVariable = 10; // Can be used directly
      return 0;
  }
  

using directive is considered less safe in large projects, as it can lead to name conflicts. It is recommended to use using declarations for selective importing of names.