Possible Duplicate:
ArgumentNullException or NullReferenceException from extension method?
So, I know that extension methods are just syntactic sugar for static helper methods, so you can happily(?) call them on null objects, and won't get a NullReferenceException automatically.
My question is, should you, as a designer of an Extension method, throw a NullReferenceException manually in the extension method - so that it behaves as much as possible like a native method. Or should you do something more conventional and throw an ArgumentNullException?
I guess it's a matter of style, and I'd probably prefer the latter option, but was wondering how far people think you should go when making extension methods look and act like native methods.
