But it is not possible as there is no unsigned/absolute zero: 0 means +0. I guess it makes things much simpler, but IMHO it makes it a bit less useful and strange.
I think if you treat infinity as a special case of NaN (which it basically is for many math systems), you get the behavior you want. A lot of people think that +/-0 represent +/-epsilon, but they really don't. +0 is the default 0, and -0 is what you get when you underflow specifically from the left.
