I was using a natural because I couldn't figure out how to do it with AAA and the other post on arguments was using a natural.
If I could just see an example using the 'starts with' followed by an 'Any' for the boolean parameter that would probably get me far enough to take it from there and write my own custom checker.
However, as far as that goes - in RM, I believe I'm able to on-the-fly set up an in-line delegate for the argument check - is that possible, something like:
using(Recorder r = new Recorder())
{
Class.Method(Args.Expect(s => s.StartWith("xyz"), Args.Any);
LastCall.Throw(new Exception("Test"));
}
I can't remember the exacts, but it was that type of functionality, and I'm sure it's in Isolator, I just can't remember or find how again - problem with frameworks is when you don't use them for a month or two because you're doing paperwork you get rusty and forget the exacts! :D