<?php
$s = "sas bab aaa";
return "<i>".$m[1]."</i>";
} else {
return "b<b>a</b>b";
}
}, $s);
echo $res;
PD9waHAKCiRzID0gInNhcyBiYWIgYWFhIjsKJHJlcyA9IHByZWdfcmVwbGFjZV9jYWxsYmFjaygnfmJhYnwoYSl+JywgZnVuY3Rpb24oJG0pIHsKCWlmIChpc3NldCgkbVsxXSkgJiYgIWVtcHR5KCRtWzFdKSkgewoJCXJldHVybiAiPGk+Ii4kbVsxXS4iPC9pPiI7Cgl9IGVsc2UgewoJCXJldHVybiAiYjxiPmE8L2I+YiI7Cgl9Cn0sICRzKTsKZWNobyAkcmVzOw==