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Groups > comp.lang.python > #19250

Re: __future__ and __rdiv__

From Terry Reedy <tjreedy@udel.edu>
Subject Re: __future__ and __rdiv__
Date 2012-01-23 03:07 -0500
References <FBA05D13-ED13-435C-9F9B-E45CB6EE8CED@gmail.com>
Newsgroups comp.lang.python
Message-ID <mailman.4955.1327306073.27778.python-list@python.org> (permalink)

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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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Re: __future__ and __rdiv__ Terry Reedy <tjreedy@udel.edu> - 2012-01-23 03:07 -0500
  Re: __future__ and __rdiv__ Duncan Booth <duncan.booth@invalid.invalid> - 2012-01-23 08:39 +0000

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