Namespaces
PHP Manual

Declaring sub-namespaces

Much like directories and files, PHP namespaces also contain the ability to specify a hierarchy of namespace names. Thus, a namespace name can be defined with sub-levels:

Example #1 Declaring a single namespace with hierarchy

<?php
namespace MyProject\Sub\Level;

const 
CONNECT_OK 1;
class 
Connection /* ... */ }
function 
connect() { /* ... */  }

?>
The above example creates constant MyProject\Sub\Level\CONNECT_OK, class MyProject\Sub\Level\Connection and function MyProject\Sub\Level\connect.


Namespaces
PHP Manual