Online PHP editor | output for AEbMH

<?php abstract class Foo { private static $instance = NULL; private function __construct() { } public static function getInstance() { return static::$instance === NULL ? static::$instance = new static() ? static::$instance; } } final class Bar extends Foo { } final class Baz extends Foo { } $bar = Bar::getInstance(); echo get_class($bar), "\n"; $baz = Baz::getInstance(); echo get_class($baz), "\n";