First, tell us what problem you're solving.

Strictly speaking, bound methods don't have an unambiguous notion of equality:

are they equal if they do the same thing, or of they do they same thing _on the same object_?

The result that you're seeing is a consequence of that same dichotomy in the minds of the .__eq__ designers, and Python Zen advises "In the face of ambiguity, refuse the temptation to guess." -- which is what you're suggesting.


On 21.06.2018 14:25, Jeroen Demeyer wrote:
Currently, we have:

>>> [].append == [].append
False

However, with a Python class:

>>> class List(list):
...     def append(self, x): super().append(x)
>>> List().append == List().append
True

In the former case, __self__ is compared using "is" and in the latter case, it is compared using "==".

I think that comparing using "==" is the right thing to do because "is" is really an implementation detail. Consider

>>> (10000).bit_length == (10000).bit_length
True
>>> (10000).bit_length == (10000+0).bit_length
False

I guess that's also the reason why CPython internally rarely uses "is" for comparisons.

See also:
- https://bugs.python.org/issue1617161
- https://bugs.python.org/issue33925

Any opinions?


Jeroen.
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--
Regards,
Ivan

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