[Python-Dev] NoneType(None) raises exception

Benjamin Peterson benjamin at python.org
Fri Apr 26 01:35:10 CEST 2013


2013/4/25 Ethan Furman <ethan at stoneleaf.us>:
> We just fixed NoneType() to return None instead of raising an exception.
>
> Another use-case for calling NoneType is working with ORMs:
>
> result = []
> for field in row:
>      type = get_type(field)      # returns int, bool, str, NoneType, ...
>      result.append(type(field))
>
>
> if field is None, the resulting call is NoneType(None), and since NoneType
> doesn't take any parameters we get an exception.
>
> Is it worth filing a bug to have NoneType accept one optional argument,
> which defaults to None, and must be None, else raise an exception?

IMO, that has no interesting semantic meaning and defining your own
none function is a perfectly acceptable way of dealing with your
problem.


--
Regards,
Benjamin


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