Question

有没有办法让自定义元类与enum34包（Python 3之前版）配合使用？

import enum
import six

class MyMeta(type):
    def __new__(cls, class_name, bases, class_dict):
        print("Does something useful.")
        return super(MyMeta, cls).__new__(cls, class_name, bases, class_dict)

@six.add_metaclass(MyMeta)
class MyClass(object):
    def __init__(self, *args, **kwargs):
        pass

MyEnum = enum.Enum('MyEnum', [('One', 1), ('Two', 2), ('Three', 3)], type=MyClass)

以上内容目前在enum_class = super(EnumMeta, metacls).__new__(metacls, cls, bases, classdict)

的enum34中引发错误

TypeError: metaclass conflict: the metaclass of a derived class must be a (non-strict) subclass of the metaclasses of all its bases

Answer 1

您应该从MyMeta的元类派生enum.Enum：

class MyMeta(type(enum.Enum)):
    ...

Answer 2

而不是enum.Enum。你应该只写Enum。那个问题就解决了。

例如：

        class MyEnumClass(Enum):
               ........

解决enum34元类冲突？

2 个答案: