.. _cannot-use-the-final-modifier-on-a-parameter:

Cannot use the final modifier on a parameter
--------------------------------------------
 
.. meta::
	:description:
		Cannot use the final modifier on a parameter: The ``final`` option is not available for promoted properties, until PHP 8.
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	:og:title: Cannot use the final modifier on a parameter
	:og:description: The ``final`` option is not available for promoted properties, until PHP 8
	:og:url: https://php-errors.readthedocs.io/en/latest/messages/cannot-use-the-final-modifier-on-a-parameter.html
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	:twitter:title: Cannot use the final modifier on a parameter
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Description
___________
 
The ``final`` option is not available for promoted properties, until PHP 8.5. Until then, the property shall be ``final`` but not ``promoted``, or it has to be declared the traditional way.

Example
_______

.. code-block:: php

   <?php
   
   class X {
       function __construct( 
           public final int $i
       ) {}
   }
   
   ?>

Solutions
_________

+ Upgrade to PHP 8.5 or more recent.
+ Remove the final property from the promoted property.
+ Create the property in the class body.

Changed Behavior
________________

This error may appear following an evolution in behavior, in previous versions. See ` <https://php-changed-behaviors.readthedocs.io/en/latest/behavior/.html>`_.