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run code in 300+ PHP versions simultaneously
<?php class Foo { private $_attributes = []; public function __get($name) { return null; // $this->_attributes[$name]; } } class Bar { public $relation; public $need; public function test() { $relation = $this->relation; if (!empty($relation->{$this->need})) { return 'Not empty'; } } } $foo = new Foo(); $bar = new Bar(); $bar->relation = $foo; $bar->need = 'slug'; var_dump($bar->test());

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32.55 ms | 402 KiB | 5 Q