Python将对象作为函数访问（不是__call__）

Question

I want to do the following: I have a container-class Container, it has attribute attr, which refers to another class OtherClass.

class OtherClass:
    def __init__(self, value): 
        self._value = value 

    def default(self): 
        retirn self._value 

    def another(self): 
        return self._value ** 2 

    def as_str(self): 
        return 'String: %s' % self._value

class Container: 
    def __init__(self, attr): 
        self.attr = OtherClass(attr)

I want to:

x = Container(2) 

x.attr # when accessing the attribute - return value from default method
2 
x.attr.another() # but also an attribute can be treated as an object 
4 
x.attr.as_str()
'String: 2'

How can I do this?

Answer 1

Not sure if this is what you need. Seems like an odd design to me

>>> class OtherClass(int):
...     def __init__(self, value): 
...         self._value = value 
...     def another(self): 
...         return self._value ** 2 
... 
>>> class Container: 
...     def __init__(self, attr): 
...         self.attr = OtherClass(attr)
... 
>>> x=Container(2)
>>> x.attr
2
>>> x.attr.another()
4

just-because-you-use-classes-doesn't-mean-it's-OO-ly gnibbler

Answer 2

除非OtherClass重写__int__() ，然后将其放入int()以获取整数值，否则您不能这样做。

Answer 3

What is attr meant to be? You can't have it both ways; either it's the return value of some function or it's an instance of OtherClass .

How about making OtherClass inherit from Integer ?