Namespace aliases - cppreference.com (original) (raw)

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] Keywords

namespace

[edit] Example

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

Output:

[edit] See also