Way OT, but does "algebra" recognize +/-0? Or is that just an artifact of 
packed notation (which is itself an artifact of Hollerith cards)?

What is -5 * 0 in fullword arithmetic? SURELY not -0.

Charles

-----Original Message-----
From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf 
Of Tony Harminc
Sent: Wednesday, September 14, 2016 2:13 PM
To: [email protected]
Subject: Re: Bypassing s322

On 14 September 2016 at 16:34, Bill Woodger <[email protected]> wrote:

> When IBM decided to use "character" comparisons where possible for numerics, 
> they had to ban the negative zero.
> Although in a decimal compare a zero is zero, no matter how signed, in 
> a character compare it is not. Ergo -ve zero could not be allowed to 
> exist. (you can of course screw things up by being deliberate, but no 
> calculation in COBOL will ever generate a -ve zero result, nor will any 
> truncation).

So in COBOL, +0 times -5 is +0, i.e the rules of algebra don't apply?
The generated code must go out of its way to accomplish this.

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