Online PHP editor | output for ZTMcu

<?php class Fish {} class Mammal {} class Whale extends Mammal {} class Human extends Mammal {} class Shark extends Fish {} function anyFish(array $collection) { foreach ($collection as $item) { if((is_array($item) && anyFish($item)) || $item instanceof Fish) { return true; } } return false; } $solar_system = [ 'mars' => [ 'dirt' => [new Human] ], 'earth' => [ 'pacific' => [new Whale, new Whale, new Whale], 'atlantic' => [new Human] ] ]; $seas = [ 'pacific' => [new Whale, new Whale, new Shark, new Whale], 'atlantic' => [new Human, new Shark] ]; $pub = [new Human, new Human]; var_dump(anyFish($solar_system)); var_dump(anyFish($seas)); var_dump(anyFish($pub));