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From: Serhiy Storchaka <storchaka@gmail.com>
Subject: Re: Minus operator versus unary minus
Date: Sat, 30 May 2015 12:32:50 +0300
References: <mkbqfn$9p0$1@ger.gmane.org> <mkbtbd$ksm$1@ger.gmane.org> <mkbuok$90v$1@ger.gmane.org>
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On 30.05.15 12:09, Peter Otten wrote:
> Serhiy Storchaka wrote:
>> On 30.05.15 10:56, Peter Otten wrote:
>>> The following modification of the collections.Counter implementation
>>>
>>> https://hg.python.org/cpython/rev/fe4efc0032b5
>>>
>>> was just checked in with the line
>>>
>>> result[elem] = 0 - count
>>>
>>> Does this have an advantage over the obvious
>>>
>>> result[elem] = -count
>>>
>>> ?
>>
>>>>> x = 0.0
>>>>> -x
>> -0.0
>>
>>
>>>>> 0 - x
>> 0.0
>
> That's a subtle difference, but does it matter in the context of the patch?

I don't know. Perhaps there is more meaningful difference for decimals.

This code is not new (see
https://hg.python.org/cpython/rev/e908ebc160f0).