Online PHP editor | output for XPW1U

<?php $haystack = "I like cats."; $needles = ['cat' => 0, 'dog' => 1]; function regex(string $haystack, array $needles) { $regex = implode('|', array_map('preg_quote', array_keys($needles))); if (!preg_match("#$regex#", $haystack, $m)) { throw new Exception('No needles were found in the haystack'); } return $needles[$m[0]]; } try { var_export(regex($haystack, $needles)); } catch (Exception $e) { echo $e->getMessage(); }