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Date: Mon, 05 Aug 2013 00:35:58 +0200
From: Markus Rother <python@markusrother.de>
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Subject: Bug? ( () == [] ) != ( ().__eq__([]) )
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Xref: csiph.com comp.lang.python:51940

Hello,

The following behaviour seen in 3.2 seems very strange to me:

As expected:
 >>> () == []
False

However:
 >>> ().__eq__([])
NotImplemented
 >>> [].__eq__(())
NotImplemented

And:
 >>> bool(NotImplemented)
True

Hence:
 >>> bool(().__eq__([]))
True
 >>> ( () == [] ) != ( ().__eq__([]) )
True

How/why can this be intended?

Thanks, everybody.

Markus R.