======================
Rule ``no_unset_cast``
======================

Variables must be set ``null`` instead of using ``(unset)`` casting.

Examples
--------

Example #1
~~~~~~~~~~

.. code-block:: diff

   --- Original
   +++ New
    <?php
   -$a = (unset) $b;
   +$a =  null;

Rule sets
---------

The rule is part of the following rule sets:

- `@PHP80Migration <./../../ruleSets/PHP80Migration.rst>`_
- `@PHP81Migration <./../../ruleSets/PHP81Migration.rst>`_
- `@PHP82Migration <./../../ruleSets/PHP82Migration.rst>`_
- `@PHP83Migration <./../../ruleSets/PHP83Migration.rst>`_
- `@PHP84Migration <./../../ruleSets/PHP84Migration.rst>`_
- `@PhpCsFixer <./../../ruleSets/PhpCsFixer.rst>`_
- `@Symfony <./../../ruleSets/Symfony.rst>`_

References
----------

- Fixer class: `PhpCsFixer\\Fixer\\CastNotation\\NoUnsetCastFixer <./../../../src/Fixer/CastNotation/NoUnsetCastFixer.php>`_
- Test class: `PhpCsFixer\\Tests\\Fixer\\CastNotation\\NoUnsetCastFixerTest <./../../../tests/Fixer/CastNotation/NoUnsetCastFixerTest.php>`_

The test class defines officially supported behaviour. Each test case is a part of our backward compatibility promise.
