在 metaclasses 的情况下,我们如何访问继承的 class 属性
How can we access inherited class attributes in case of metaclasses
即使 var1
是 ChildClass
class 的成员,为什么我无法使用 ChildClass.var1
[=17= 访问 var1
]
class MyType(type):
def __getattribute__(self, name):
print('attr lookup for %s' % str(name))
return object.__getattribute__(self, name)
class BaseClass(object):
__metaclass__ = MyType
var1 = 5
class ChildClass(BaseClass):
var2 = 6
print(ChildClass.var2) #works
print(ChildClass.var1) #fails
我收到以下错误
AttributeError: 'MyType' object has no attribute 'var1'
谢谢
因为 MyType
是 type
,所以使用 type.__getattribute__
而不是 object.__getattribute__
:
class MyType(type):
def __getattribute__(self, name):
print('attr lookup for %s' % str(name))
return type.__getattribute__(self, name)
即使 var1
是 ChildClass
class 的成员,为什么我无法使用 ChildClass.var1
[=17= 访问 var1
]
class MyType(type):
def __getattribute__(self, name):
print('attr lookup for %s' % str(name))
return object.__getattribute__(self, name)
class BaseClass(object):
__metaclass__ = MyType
var1 = 5
class ChildClass(BaseClass):
var2 = 6
print(ChildClass.var2) #works
print(ChildClass.var1) #fails
我收到以下错误
AttributeError: 'MyType' object has no attribute 'var1'
谢谢
因为 MyType
是 type
,所以使用 type.__getattribute__
而不是 object.__getattribute__
:
class MyType(type):
def __getattribute__(self, name):
print('attr lookup for %s' % str(name))
return type.__getattribute__(self, name)