Yes. That's my point. I don't like that error.
On 2019-12-31 3:23 p.m., Anders Hovmöller wrote:
Tried that. Got:
TypeError: metaclass conflict: the metaclass of a derived class must be a
(non-strict) subclass of the metaclasses of all its bases
You should probably try the example you're trying to post before posting it.
> On 31 Dec 2019, at 19:19, Soni L. <fakedme...@gmail.com> wrote:
>
> Okay. How about this then:
>
> class MM(type):
> def __subclasscheck__(self, subclass):
> return issubclass(subclass, type)
>
>
> class M(type, metaclass=MM):
> pass
>
>
> class N(type):
> pass
>
>
> class C(metaclass=M):
> pass
>
>
> class D(metaclass=N):
> pass
>
>
> class E(C, D, metaclass=N):
> pass
>
>
> def main():
> assert type(E) is N and issubclass(E, C)
>
>
> main()
>
>> On 2019-12-31 3:16 p.m., Anders Hovmöller wrote:
>> You forgot something in that example I think because it doesn't actually do anything
that can "not work".
>>
>> > On 31 Dec 2019, at 18:41, Soni L. <fakedme...@gmail.com> wrote:
>> > > I would like this code to work, but currently python ignores
__subclasscheck__ in many places where it checks for subclasses:
>> > > class MM(type):
>> > def __subclasscheck__(self, subclass):
>> > return issubclass(subclass, type)
>> > > > class M(type, metaclass=MM):
>> > pass
>> > > > class N(type):
>> > pass
>> > > > class C(metaclass=M):
>> > pass
>> > > > class D(metaclass=N):
>> > pass
>> > > > class E(C, D, metaclass=N):
>> > pass
>> > > > def main():
>> > e = E()
>> > > > main()
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