.. _copy-of-$globals:

Copy Of $GLOBALS
================
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		Copy Of $GLOBALS: Until PHP 8.
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	:og:title: Copy Of $GLOBALS
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Until PHP 8.1, copying $GLOBALS into another variable was made by reference: modifying the values in the copy was also modifying the original. Since PHP 8.1, the copy is a copy by value: this means that changing something in the copy will not be changed in the original ``$GLOBALS`` variable.

PHP code
________
.. code-block:: php

   <?php
   $a = 1;
   
   $globals = $GLOBALS; // Ostensibly by-value copy
   $globals['a'] = 2;
   var_dump($a); // int(2)
   ?>

Before
______
.. code-block:: output

   int(2)
   

After
______
.. code-block:: output

   int(1)
   


PHP version change
__________________
This behavior changed in 8.1


Analyzer
_________

  + `Php/GlobalCopy <https://exakat.readthedocs.io/en/latest/Reference/Rules/Php/GlobalCopy.html>`_