Comment 1 for bug 1208610

So this basically builds a language for including and excluding test, which is exactly what a regex is. What happens if someone includes two different patterns and excludes two different patterns? Is it evaluated left to right or union-adds then subtract all excludes? What if someone can't exclude precisely and wants to exclude then include?

I'm open to the idea of having a meta language rather than just regexp, but it needs to be designed, with care, or it just becomes a wart.