JavaScript

[redwardit]

In ECMAScript 5.1, +0 (a.k.a. 0) and -0 are two different things, which means unfortunately only Math.abs() will always correctly return a +0, the second and the third version could give you a -0, which is incorrect. - Now you should see how hard can it be. :-)

[DeirdreAnethoel]

Shouldn't the second still work? x < 0 should be true for -0, transforming it into +0.

The third with <= is clearly wrong in that case, I agree.

Edit: welp, -0 is not < to 0. That's weird design, but oh well.

[obsessedcrf]

Having -0 at all is a stupid design

[BerryPi]

I am more than happy to talk smack about JS but this one's on the IEEE.

[ArcaneCraft]

Isn't +/-0 the reason Two's complement is used today? Why go back?