.. _null-cannot-be-marked-as-nullable:

null cannot be marked as nullable
---------------------------------
 
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		null cannot be marked as nullable: Since PHP 8.
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Description
___________
 
Since PHP 8.2, ``null`` (like ``false`` and ``true``) can be used directly as a standalone type. But ``null`` already means exactly one thing: the value ``null``. Marking it nullable with a leading ``?``, as in ``?null``, would only mean ``null or null``, which is entirely redundant, so PHP rejects it.

Example
_______

.. code-block:: php

   <?php
   
   function test(): ?null
   {
   }
   
   ?>


Literal Examples
****************
+ null cannot be marked as nullable

Solutions
_________

+ Remove the ``?`` and use ``null`` on its own.

Related Error Messages
______________________

+ :ref:`type-contains-both-true-and-false,-bool-must-be-used-instead`
+ :ref:`duplicate-type-%s-is-redundant`

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>`_.