Python：协议元类带有仅阅读属性的元素

Question

我想实现具有较少样板的只读属性的协议。简而言之：

# I want to reduce boilerplate of the following.
class MyVerboseProtocol(Protocol)
    @property
    def x(self):
        return x


# I want this to be functionally equivalent to MyVerboseProtocol
class MyProtocol(Protocol)
     x # this should be read-only


class MyClass(MyProtocol)
    x = 5


my_class = MyClass()
print(my_class.x) # should print 5
myclass.x = 4 # should raise some exception

我尝试了一个元素，但带有协议的东西使该属性并非仅阅读：

class MyMetaProtocol(type(Protocol) # needs type(Protocol) or something won't resolve
    @property
    def x(self): # pylance seems to want self here
        return self.x


class MyProtocol(Protocol, metaclass=MyMetaProtocol)
    x


class MyClass(MyProtocol)
    x = 5


my_class = MyClass()
print(my_class.x) # should print 5
myclass.x = 4 # seems fine??

Answer 1

我会选择“简单更好”。违反协议背后的直觉可能不值得节省几下按键。

另一个选择是类装饰器，但如果我们首先有能力修改类，那么它似乎没有多大意义。