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run code in 300+ PHP versions simultaneously
<?php class A { protected static $_instance; protected function __construct() {} public static function getInstance() { if (self::$_instance === null) { self::$_instance = new static(); } return self::$_instance; } } class B extends A { public function hi() { echo 'HI'; } } echo get_class(B::getInstance()); $b = B::getInstance(); $b->hi();
Output for 5.4.2 - 5.4.45, 5.5.24 - 5.5.35, 5.6.8 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
BHI
preferences:
214.09 ms | 404 KiB | 269 Q