[Python-Dev] NoneType(None) raises exception
ethan at stoneleaf.us
Fri Apr 26 02:43:21 CEST 2013
On 04/25/2013 05:27 PM, Steven D'Aprano wrote:
> On 26/04/13 09:56, MRAB wrote:
>> On the other hand:
>> type(value)(value) == value
>> would return True for the built-in types (will certain exceptions, such
>> as when value is float("NaN")).
> Not an exception, that works fine in 3.3:
>>>> value = float('nan')
You missed the == part:
>>> type(value)(value) == value
>> Let's ask the Zen:
>> Special cases aren't special enough to break the rules.
>> Although practicality beats purity.
> I cannot think of any use-case where I would actively want
> NoneType(None) to fail. That would be like having bool(True)
> raise an exception.
> On the other hand, NoneType(x) for any other x ought to fail.
Or, since the purpose of NoneType is to return None, just return None no matter what!
Kind'a like 0 * anything == 0.
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