[Pharo-project] Regular expression

Hi, Is it possible to use the VB-Regexp package to construct a single regular expression that ensures a string is alphanumeric and contains both at least one number and alphabetic character. Looking at the regexp package and documentation it doesn't appear so. In javascript or perl you use something like this with lookahead assertions: ^(?=.*[a-zA-Z])(?=.*[0-9]).*$ I have something working using multiple regexp's but wondered if a more typical regexp was possible using the package ? Thanks