[Python-Dev] Decimal <-> float comparisons in py3k.

[Nick Coghlan]

Steven D'Aprano wrote:
> But no such problems arise with comparisons, which will always return a 
> bool, and will avoid the current ... interesting ... behaviour. In 3.1:
> 
>>>> Decimal(1) == 1 == 1.0
> True
>>>> Decimal(1) == 1.0
> False
>>>> Decimal.from_float(1.0) == 1 == 1.0
> True
>>>> Decimal.from_float(1.0) == 1.0
> False
> 
> Replacing False with an exception doesn't make it any less bizarre.

Allowing the comparisons also doesn't introduce the potential for large
cumulative errors which are possible when actual implicit arithmetic
conversions are allowed.

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia
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