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Bug? ( () == [] ) != ( ().__eq__([]) )

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Date Mon, 05 Aug 2013 00:35:58 +0200
From Markus Rother <python@markusrother.de>
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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.

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Bug? ( () == [] ) != ( ().__eq__([]) ) Markus Rother <python@markusrother.de> - 2013-08-05 00:35 +0200

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