Re: Python3 doc, operator reflection

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Date	Mon, 28 Oct 2013 23:23:32 +1100
Subject	Re: Python3 doc, operator reflection
From	Chris Angelico <rosuav@gmail.com>
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On Mon, Oct 28, 2013 at 11:00 PM, Johannes Bauer <dfnsonfsduifb@gmx.de> wrote:
>> There are no swapped-argument versions of these methods (to be used when the left argument does not support the operation but the right argument does); rather, __lt__() and __gt__() are each other’s reflection, __le__() and __ge__() are each other’s reflection, and __eq__() and __ne__() are their own reflection.
>
> But shouldn't __lt__ be the reflection or __ge__ and __gt__ the
> reflection of __le__?

lt is the negation of ge, but it's the reflection of gt. Consider this:

1 < 2
2 > 1

If Python can't ask 1 if it's less than 2, it'll ask 2 if it's greater than 1.

ChrisA

Thread

Python3 doc, operator reflection Johannes Bauer <dfnsonfsduifb@gmx.de> - 2013-10-28 13:00 +0100
  Re: Python3 doc, operator reflection Chris Angelico <rosuav@gmail.com> - 2013-10-28 23:23 +1100
    Re: Python3 doc, operator reflection Johannes Bauer <dfnsonfsduifb@gmx.de> - 2013-10-28 13:45 +0100
  Re: Python3 doc, operator reflection random832@fastmail.us - 2013-10-28 14:31 -0400

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