Namespace aliases
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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.
Contents
[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
[edit] Example
Run this code
#include <iostream> namespace foo { namespace bar { namespace baz { int qux = 42; } } } namespace fbz = foo::bar::baz; int main() { std::cout << fbz::qux << '\n'; }
Output:
42
[edit] See also
namespace declaration
identifies a namespace[edit]