Namespace aliases

< cpp‎ | language

Namespace aliases allow the programmer to define an alternate name for a namespace.

They are commonly used as a convenient shortcut for long or deeply-nested namespaces.


[edit] Syntax

namespace alias_name = ns_name; (1)
namespace alias_name = ::ns_name; (2)
namespace alias_name = nested_name::ns_name; (3)

[edit] Explanation

The new alias alias_name provides an alternate method of accessing ns_name.

alias_name must be a name not previously used. alias_name is valid for the duration of the scope in which it is introduced.

[edit] Example

#include <iostream>
namespace foo {
    namespace bar {
         namespace baz {
             int qux = 42;
namespace fbz = foo::bar::baz;
int main()
    std::cout << fbz::qux << '\n';



[edit] See also

namespace declaration identifies a namespace