On Tue, Dec 8, 2009 at 10:18 AM, Bill Baxter <[email protected]> wrote: >> I agree. Then at least why not make the type of the exponent unsigned? That >> gives the type system a fighting chance (via e.g. value range propagation). >> Give Willy a chance! > > Honestly, I don't really understand this concern with range > propagation. Seems to me that allowing a negative exponent doesn't > much expand the range, if a truncation rule is used. The result is > either undefined, 0 or 1. The range is much greater with a > non-negative exponent. Could be undefined, zero, or most any negative > or positive number.
This was meant sincerely, by the way. As in, I am ignorant about this issue (the trouble with range propagation and negative exponents) and would appreciate it if someone could explain it. --bb
