Description
A C++ namespace is used to group together a set of function, type, and data definitions. For example, in this code:
namespace A { void f() {} int x = 100; }there is a namespace A with two members f() and x. Members of the namespace can be referenced by names like A::f() or by saying using namespace A or using A::f. A namespace represents a logical grouping of related declarations.
A namespace may be split into several parts, for example by saying:
namespace A { void f() {} } ... namespace A { void g() {} }which declares only one namespace, with two members f() and g().
Concept
The sample program defines a namespace, and shows how members of the namespace are distinguished from global functions and data. To access namespace members, their names are prefaced with A::.
Special Notes:
The C++ Standard Library makes heavy use of namespaces, for example to define the std namespace that groups together standard functions and types. You frequently see:
using namespace std;at the top of programs, which means that members of the standard library are to be made available to the program.
Supported
Supported
Supported