Online PHP editor | refs for tTRT6

<?php class struct { private $args; function __construct(array $args) { $this->args = $args; } function __invoke(callable $signature = NULL) : array { if ($signature === NULL) return $this->signature(...array_values($this->args)); return $signature(...array_values($this->args)); } } final class Dinosaur extends struct { function signature(int $legs) : array { return get_defined_vars(); } } $two_legs = function(Dinosaur $dino) : Dinosaur { $trex = $dino(); $trex['legs'] = 2; return new Dinosaur($trex); }; var_dump($two_legs(new Dinosaur([0])));