__future__ and __rdiv__

Terry Reedy tjreedy at udel.edu
Mon Jan 23 03:07:38 EST 2012

On 1/23/2012 12:22 AM, Massimo Di Pierro wrote:
> Hello everybody,
> I hope somebody could help me with this problem. If this is not the right place to ask, please direct me to the right place and apologies.
> I am using Python 2.7 and I am writing some code I want to work on 3.x as well. The problem can be reproduced with this code:
> # from __future__ import division
> class Number(object):
>      def __init__(self,number):
>          self.number=number
>      def __rdiv__(self,other):
>          return other/self.number
> print 10/Number(5)
> It prints 2 as I expect. But if I uncomment the first line, I get:

If you want to get 2 rather than 2.0 after uncommenting, then I believe 
you should use // and __floordiv__. In fact, you do not even need the 
future import. But if you mean for Number to be like a float rather than 
int, do as you are (with / and __truediv__).

Terry Jan Reedy

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