Online PHP editor | refs for f2BY0

<?php if ( ! defined('PHP_EOL')) { define('PHP_EOL', "\n"); } $array = array('a' => false, 'b' => null, 'c' => '', 'd' => true); function asBool($value) { return $value ? 'true' : 'false' ; } foreach ($array as $k => $v) { printf( '"%s" => "%s" isset = %s ake = %s' . PHP_EOL, $k, $v, asBool(isset($array[ $k ])), asBool(array_key_exists($k, $array)) ); }