You are doing more work than you need to. Remember that mathematical comparisons return booleans, and booleans can be directly compared. 

if ($x<0 == $y<0) {
  print "$x and $y have the same sign";
}

[download]

(($x ^ $y) < 0) would probably also work assuming they are integers. I think the trick with abs or the comparison operator would probably actually be less efficient than doing a comparison. Using multiplication is going to be slow as well.

BTW the sign of zero isnt a theological debate, it is an implementation detail of the machine you are working on and the data types you are using. :-)

---
$world=~s/war/peace/g

In reply to Re: Seeing if two numbers have the same sign by demerphq
in thread Seeing if two numbers have the same sign by grinder

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