operator overloading and unchecked vs checked

[keithv]

I've created my own value type which will overload
the "+" operator. I have two routines to do addition,
differing only in that one throws an error on overflow.

Is there a way to get the compiler to apply unchecked
and checked semantics to my type: calling MyAdd() for
unchecked code and MyAdd.ovl() for checked code?

Thanks,
Keith