- var_dump: documentation ( source)
- preg_match_all: documentation ( source)
<?php
$regex = '/^[a-z0-9!#$%&\'*+\/=?^_`{|}~-]+(?:\.[a-z0-9!#$%&\'*+\/=?^_`{|}~-]+)*@(?:[a-z0-9][-a-z0-9]*\.)*(?:[a-z0-9][-a-z0-9]{0,62})\.(?:(?:[a-z]{2}\.)?[a-z]{2,4}|museum|travel)/i';
$email = 'uni-direct@uws.ac.uk';
preg_match_all($regex, $email, $matches);
var_dump($matches);