mixed Is Now A Keyword

mixed was introduced in PHP 8.0 as a new type. As a side effect, it is now a PHP keyword, and it is not possible to create classes, functions or constants with that name.

PHP code

<?php

class mixed {
     function __construct() {
             echo __METHOD__;
     }
}

new mixed;

?>

Before

mixed::__construct

After

PHP Fatal error:  Cannot use 'mixed' as class name as it is reserved in /codes/mixedKeyword.php on line 3

Fatal error: Cannot use 'mixed' as class name as it is reserved in /codes/mixedKeyword.php on line 3

PHP version change

This behavior changed in 8.0

Error Messages