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Postings from February 2003
abigail@abigail.nl (via RT) wrote: > $ perl -wle '$x = 1597009560; print $x ** 2' > 2.5504395347313936e+18 $ perl -wl -MMath::BigInt=:constant -e '$x = 1597009560; print $x ** 2' 2550439534731393600 Just because Perl guessed right one time and not the other doesn't mean that you should rely on consistent large number behavior. There is always going to be some point where NV's will happen when you would expect UV or IV's to be used. If you care about the correctness of your math, use M::BI. I think I can explain why Perl made the choices it did (and I can even look at the source code to see if I am right ;~), but I cannot believe that this should be considered to be a bug. I suspect the multiplication is attempted first using the IV's for speed, falling back to the NV's if the IV's overflow. The exponential goes straight for the jugular and uses NV's preferrentially, since the odds of overflowing the IV slot are so much greater. John -- John Peacock Director of Information Research and Technology Rowman & Littlefield Publishing Group 4501 Forbes Boulevard Suite H Lanham, MD 20706 301-459-3366 x.5010 fax 301-429-5748Thread Previous