gh-116241: Add support of multiple inheritance with typing.NamedTuple#31781
gh-116241: Add support of multiple inheritance with typing.NamedTuple#31781serhiy-storchaka wants to merge 8 commits into
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JelleZijlstra
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I think this goes too far because it's not realistic to expect type checkers to support arbitrary base classes on NamedTuple. Also, there haven't been any user requests that I can see for multiple inheritance with anything other than Generic. So I'd prefer to merge the other PR that allows multiple inheritance with Generic only.
I also think it makes sense to only allow multiple inheritance with |
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So, let's just close this? |
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Jason-Y-Z
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people really need arbitrary multiple inheritance for whatever reason
Thanks for reopening! This looks like the case now indeed
CoolCat467
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Looks great! I ended up doing nearly exactly the same thing in some code of my own to get around this limitation.
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Thank you @AlexWaygood and @gvanrossum. Updated to 3.14 and applied the suggestions. |
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Given that we've had multiple requests for this, I'm okay with landing it. But please get sign-offs from @gvanrossum and @JelleZijlstra before merging.
gvanrossum
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Let's do it! (I approve of the idea, I haven't carefully reviewed the code.)
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I'm OK with this given the discussion on the issue; will take another look at the code soon. |
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Reminder for this: the 3.14 beta freeze is in two weeks. |
picnixz
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That'd be great to have. I needed this more than once!
| disallowed in Python 3.15. To create a NamedTuple class with 0 fields, | ||
| use ``class NT(NamedTuple): pass`` or ``NT = NamedTuple("NT", [])``. | ||
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| .. versionchanged:: 3.14 |
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| .. versionchanged:: 3.14 | |
| .. versionchanged:: next |
| self.assertEqual(a.y, 5) | ||
| self.assertEqual(len(a), 1) | ||
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| class Y(A, NamedTuple): |
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Maybe add a test to check the order of the members as well when doing unpacking? And maybe test class Z(X, Y, NamedTuple)? (I don't know if this leads to a MRO incompatibilty though)
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It will be error. This is tested in the next test.
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This PR is stale because it has been open for 30 days with no activity. |
| for base in bases: | ||
| if base is not _NamedTuple and base is not Generic: | ||
| raise TypeError( | ||
| 'can only inherit from a NamedTuple type and Generic') |
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Please consider addressing https://gist.github.com/johnslavik/4d0e22df6cb61868f74269fe7d401f5b.
https://bugs.python.org/issue43923
NamedTuplecan't inherit from another class #116241