php 한글 메뉴얼 도움말 검색 사이트 Defining multiple namespaces in the same file [language.namespaces.definitionmultiple]

Defining multiple namespaces in the same file

(PHP 5 >= 5.3.0)

Multiple namespaces may also be declared in the same file. There are two allowed syntaxes.

Example #1 Declaring multiple namespaces, simple combination syntax


<?php
namespace MyProject;

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

namespace AnotherProject;

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

This syntax is not recommended for combining namespaces into a single file. Instead it is recommended to use the alternate bracketed syntax.

Example #2 Declaring multiple namespaces, bracketed syntax


<?php
namespace MyProject {

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

namespace AnotherProject {

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

It is strongly discouraged as a coding practice to combine multiple namespaces into the same file. The primary use case is to combine multiple PHP scripts into the same file.

To combine global non-namespaced code with namespaced code, only bracketed syntax is supported. Global code should be encased in a namespace statement with no namespace name as in:

Example #3 Declaring multiple namespaces and unnamespaced code


<?php
namespace MyProject {

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

namespace { // global code
session_start();
$a = MyProject\connect();
echo MyProject\Connection::start();
}
?>

No PHP code may exist outside of the namespace brackets except for an opening declare statement.

Example #4 Declaring multiple namespaces and unnamespaced code


<?php
declare(encoding='UTF-8');
namespace MyProject {

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

namespace { // global code
session_start();
$a = MyProject\connect();
echo MyProject\Connection::start();
}
?>