.. _key-element-cannot-be-a-reference:

Key element cannot be a reference
---------------------------------
 
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		Key element cannot be a reference: In a foreach() loop, the value may be a reference, when it needs to be updated.
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Description
___________
 
In a foreach() loop, the value may be a reference, when it needs to be updated. The key, on the other hand, cannot be changed, and hence, cannot have a reference.

Example
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.. code-block:: php

   <?php
   
   foreach($array as &$key => $value) {}
   
   ?>

Solutions
_________

+ Remove the reference from the key.
+ Use array_flip() to make the keys the values, and update them, then use the same function again.