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Re: Is signed zero always available?

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Subject Re: Is signed zero always available?
Date Wed, 22 Jun 2016 10:34:48 -0400
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On Wed, Jun 22, 2016, at 10:19, Grant Edwards wrote:
> 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.

AIUI, native C integers have never reliably supported signed zero even
with representations that naively seem to have it. There's no
well-defined way to detect it - no int version of copysign, for instance
- and implementations are free to erase the distinction on every
load/store or define one of them to be a trap representation.

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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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