## I don’t even recognize you anymore php

$factorial = function($a) use (&$factorial){ if($a <= 0){ return null; } if($a === 1){ return 1; } return $a * $factorial($a – 1); }; assert(null === $factorial(-1)); assert(1 === $factorial(1)); assert(120 === $factorial(5));$factorial = function($a) use (&$factorial){ if($a <= 0){ return null; } if($a === 1){ return 1; } return $a * $factorial($a – 1); }; assert(null === $factorial(-1)); assert(1… Read more →