Online PHP editor | output for YDJQH

<?php interface CommandInterface() {} abstract class AbstractCommand implements CommandInterface {} interface PrefixableCommandInterface {} abstract class PrefixableCommand extends AbstractCommand implements PrefixableCommandInterface { } class StringSet extends PrefixableCommand {} class Tester { public function executeCommand(CommandInterface $command) {} } $t = new Tester(); $t->executeCommand(new StringSet);