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run code in 500+ PHP versions simultaneously
<?php class Flextype { protected static $instance = null; public static function instance() { return !isset(self::$instance) and self::$instance = new Flextype(); } } var_export(Flextype::instance());
Output for 5.6.38 - 5.6.40, 7.0.33, 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 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
true
preferences:
101.76 ms | 1607 KiB | 4 Q