Non-zero save gas case

[0xKarl98]

As you mentioned , in non-zero case , we should set it as nonZero != 0 in order to save 6 gas .

But what if the nonZero goes negative , like nonZero = -1 .

How can nonZero != 0 be equal to nonZero > 0 , under such condition

[transmissions11]

was for unsigned integers