3.8.1 Fully qualified names

Every namespace and type has a fully qualified name, which uniquely identifies the namespace or type amongst all others. The fully qualified name of a namespace or type N is determined as follows:

• If N is a member of the global namespace, its fully qualified name is N.
• Otherwise, its fully qualified name is S.N, where S is the fully qualified name of the namespace or type in which N is declared.

In other words, the fully qualified name of N is the complete hierarchical path of identifiers that lead to N, starting from the global namespace. Because every member of a namespace or type must have a unique name, it follows that the fully qualified name of a namespace or type is always unique.

The example below shows several namespace and type declarations along with their associated fully qualified names.

class A {}            // A
namespace X            // X
{
   class B            // X.B
   {
      class C {}      // X.B.C
   }
   namespace Y         // X.Y
   {
      class D {}      // X.Y.D
   }
}
namespace X.Y         // X.Y
{
   class E {}         // X.Y.E
}