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A comment on Negative Base. Parent comment

Re:Negative Base by pphysch on Thursday June 28, 2018 @02:48PM (#17419444)
Are there common languages where -0 != +0? Or are you implying that this would be a good decision when creating a new language?
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Re:Negative Base by kybernetikos on Thursday June 28, 2018 @07:29PM (#17421316)
javascript:

    > 1/(-0)
    -Infinity
    > 1/0
    Infinity
    > Object.is(0, -0)
    false
Of course = doesn't actually test equality in javascript. == reports -0 as being equal to +0, but Object.is reports them as different.
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Re:Negative Base by earenndil on Friday June 29, 2018 @01:47AM (#17422657)
See now, I contest this particular defense because it groups together 'javascript' and 'good decision'.
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Re:Negative Base by foxhill on Thursday June 28, 2018 @04:34PM (#17420244)
basically every language with IEEE-754[1] compliance..!

[1] - https://en.m.wikipedia.org/wiki/IEEE_754

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Re:Negative Base by bzbarsky on Friday June 29, 2018 @01:26AM (#17422593)
I'd think that in all those languages, -0 == +0 tests true, though. In JavaScript even -0 === +0 tests true.

The only way to tell them apart in general is to divide by them. In some languages you might be able to type-pun and examine the bit pattern, or do things like Object.is() or whatnot.

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Re:Negative Base by saagarjha on Thursday June 28, 2018 @06:28PM (#17420991)
But only when imposing a total ordering.
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Re:Negative Base by foxhill on Thursday June 28, 2018 @06:33PM (#17421011)
that’s not the case, in IEE754 floating point, zero is signed - i.e negative and positive zero are distinct values
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Re:Negative Base by saagarjha on Thursday June 28, 2018 @08:46PM (#17421620)
But the standard comparison operators don’t distinguish them.
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