$re = '/[a-zA-Z.0-9\n!)(]*(\s[&|]\s)/';
$str = 'permission.test1 & permission.test2
permission.test1 | permission.test2
permission.test1 | !permission.test2
permission.test1 | (permission.test2 & permission.test3)';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php