[Python-Dev] NoneType(None) raises exception

Antoine Pitrou solipsis at pitrou.net
Fri Apr 26 09:01:07 CEST 2013

On Thu, 25 Apr 2013 16:09:41 -0700
Ethan Furman <ethan at stoneleaf.us> wrote:
> 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))

I don't understand what the use case is. If you already have a value of
None, why do you call NoneType on it again?

Perhaps you should write:

   if not isinstance(type, field):
       field = type(field)



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