Regular expressions in web-proxy module

RouterOS General
1

Hi,
where can I find detailed description of web-proxy regular expressions usage? There are only few lines in manual.
For example:

  1. Can I use range in ? For example [0-9] for numbers?
  2. What about other characters? Is it possible to use [a-g]?
2

http://www.google.com/search?q=regex