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Re: Is signed zero always available?

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From Grant Edwards <grant.b.edwards@gmail.com>
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Subject Re: Is signed zero always available?
Date Wed, 22 Jun 2016 14:19:32 +0000 (UTC)
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On 2016-06-22, Steven D'Aprano <steve@pearwood.info> wrote:
> Both IEEE-754 floats and Decimals support signed zeroes, that is -0.0 and
> 0.0 are two distinct (but equal) values.
>
> (There is only one int zero: -0 and 0 are the same value.)

Is that guaranteed by Python, or just a side-effect of the
implementation?  Back in the days when Python used native C integers I
think the latter.  Now that Python implements it's own
arbitrary-length ints, it may be the former.

> Signed Decimal zero should always be available. What about signed float
> zero? Are there any platforms where Python is available that don't support
> signed zeroes?

-- 
Grant Edwards               grant.b.edwards        Yow! This ASEXUAL PIG
                                  at               really BOILS my BLOOD
                              gmail.com            ... He's so ... so
                                                   ... URGENT!!

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Thread

Is signed zero always available? Steven D'Aprano <steve@pearwood.info> - 2016-06-22 23:27 +1000
  Re: Is signed zero always available? Grant Edwards <grant.b.edwards@gmail.com> - 2016-06-22 14:19 +0000
  Re: Is signed zero always available? Random832 <random832@fastmail.com> - 2016-06-22 10:34 -0400
  Re: Is signed zero always available? Grant Edwards <grant.b.edwards@gmail.com> - 2016-06-22 14:59 +0000
  Re: Is signed zero always available? Christopher Reimer <christopher_reimer@icloud.com> - 2016-06-22 15:50 -0700
    Re: Is signed zero always available? Steven D'Aprano <steve@pearwood.info> - 2016-06-23 11:16 +1000
  Re: Is signed zero always available? Michael Selik <michael.selik@gmail.com> - 2016-06-23 00:34 +0000
  Re: Is signed zero always available? Grant Edwards <grant.b.edwards@gmail.com> - 2016-06-23 02:48 +0000

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