3v4l.org

run code in 300+ PHP versions simultaneously
<?php class X { protected $x; } class Y extends X { public function __construct($x) { $this->x = $x; // Hover in PHPStorm "Field Declared Dynamically" } }
Output for 5.6.0 - 5.6.30, 7.0.0 - 7.0.24, 7.1.0 - 7.1.20, 7.2.6 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
preferences:
96.3 ms | 1582 KiB | 4 Q