PHP: Global space

Using namespaces: fallback to global function/constant

[edit] Last updated: Fri, 25 May 2012

Global space

(PHP 5 >= 5.3.0)

Without any namespace definition, all class and function definitions are placed into the global space - as it was in PHP before namespaces were supported. Prefixing a name with \ will specify that the name is required from the global space even in the context of the namespace.

Example #1 Using global space specification


<?php
namespace A\B\C;

/* This function is A\B\C\fopen */
function fopen() { 
     /* ... */
     $f = \fopen(...); // call global fopen
     return $f;
} 
?>

add a note User Contributed Notes Global space

xmarcos at gmail dot com 21-May-2012 10:08


That's the expected behavior, you have to declare the namespace at the top of the file to "extend" it. 



If you include a global namespaced file, it will operate on the global namespace.

routinet 29-Aug-2011 02:22


Included files will default to the global namespace.


<?php


//test.php


namespace test {


  include 'test1.inc';


  echo '-',__NAMESPACE__,'-<br />';


}


?>





<?php


//test1.inc


  echo '-',__NAMESPACE__,'-<br />';


?>





Results of test.php:





--


-test-

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