subclassing complex

[BiDi]

On Aug 30, 6:18 am, Patrick Maupin <pmau... at gmail.com> wrote:
> On Aug 29, 4:24 am, Peter Otten <__pete... at web.de> wrote:
>
>
>
> > A minimal example is
>
> > >>> class Complex(complex):
>
> > ...     def __radd__(self, other): print "radd"
> > ...>>> 1j + Complex()
>
> > 1j
>
> > versus
>
> > >>> class Int(int):
>
> > ...     def __radd__(self, other): print "radd"
> > ...>>> 1 + Int()
>
> > radd
>
> > I think the complex subclass should behave like the int subclass.
> > To get an authoritative answer you should file a bug report.
>
> Hmm, good point.  I shouldn't look at newsgroups when I'm too tired to
> see the whole problem.
>
> According to the documentation athttp://docs.python.org/ref/numeric-types.html:
>
> "Note: If the right operand's type is a subclass of the left operand's
> type and that subclass provides the reflected method for the
> operation, this method will be called before the left operand's non-
> reflected method. This behavior allows subclasses to override their
> ancestors' operations."
>
> I think this makes it pretty clear that the OP found a bug in how
> complex works.  (Before I read this note, I would have assumed that
> the int() handling was broken, but it looks like a supportable design
> decision.  Probably whoever implemented it wasn't even thinking about
> complex numbers, but for consistency, I would think they should be
> made to work the same.)
>
> Regards,
> Pat

Thanks for the comments. I have filed it as an issue.

Regards

Blair