[Cfp-interest 1888] Re: Negative

[Damian McGuckin]

On Sun, 10 Jan 2021, Jim Thomas wrote:

> Summary: The term 'negative' is ambiguous when talking about zero.
> 
> Is -0.0 negative? Is it nonnegative? Is +0.0 positive? We believe
> that:
>
>  *  negative is less than zero
>  *  positive is greater than zero
>  *  -0.0 and +0.0 are neither negative nor positive values
>  *  -0.0 has a negative sign
>  *  +0.0 has a positive sign
> 
> However, -0.0 and +0.0 are both nonnegative and nonpositive.

Are we looking for a tight definitive explanation?

I looked at Overton's text book and found that less precise than the 
above. Scary. I need to look at Muller's book and the standard.

> What is a ?negative signed value?? I believe it?s intended to mean a 
> signed value with a negative sign, though it might be interpreted as a 
> signed value that its negative. Using an adverb might help: negatively 
> signed value.

That is certainly more correct English.

> What should happen with NaNs? I don?t believe C says that NaN values are
> signed, or unsigned.

I will get back to you on that.

Regards - Damian

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