<?php global $y; class x { static $a; public $b = 2; function y(Stdclass $y = null, $yy = 2, Stdclass $yyy) { } } trait t { static $at; public $bt = 2; function y(Stdclass $yt = null, $yyt = 2, Stdclass $yyyt) { $real = 3; } } Stdclass::$staticproperty = 0; $o->{$dynamicProperty} = 0;