Daniel Keep Wrote: > > Since everyone seemed to miss the point I was trying to make, I'll be > more explicit. > > My point was that it's all very well to say "you should know X" and you > can even be totally right about that, but it doesn't mean behaviour > based on X is necessarily intuitive or desirable. > > Walter specifically said that "I don't feel that 2s-complement > arithmetic is in any way an advanced programming topic". I agree. I > was trying to point out that even very experienced people who would > surely know what's going on in the hardware can get it wrong.
I agree with this. However, even though experienced programmers can write 2s complement math with bugs, in this particular case, there is *no* correct way to do it. So it's impossible to get it right :) Any opposing view would have to include what obtaining the unsigned negation of an unsigned value is useful for. And literals don't count because they're easily expressed otherwise :) -Steve
