如何将 class 的实例传递到其构造函数中的属性中，并让这些属性访问初始化的属性？

Question

say I have 3 classes in python foo,bar and baz as follows:

class Foo(object):
    a=9
    def __init__(self):
        self.bar= Bar(Foo)
        self.baz = Baz(Foo)

class Bar(object):
    def __init__(self,Foo):
        self.a = Foo.a

    def f(self,b):
        return self.a*b

class Baz(object):
    def __init__(self,Foo):
        self.b = Foo.bar.f(8)
        print(self.b)

k=Foo()

Doing it as such raises the error:

AttributeError: type object 'foo' has no attribute 'bar'

unsure how to proceed as I would like to pass in that class's instance of itself into the constructors of other classes and have those instance attributes accessible by others within the constructor. I have looked around but unfortunately have not found something similar in nature within the scope of python

Answer 1

You want to pass self (the instance of Foo being initialized) to Bar and Baz , not the class Foo itself.

class Foo(object):
    a=9
    def __init__(self):
        self.bar = Bar(self)
        self.baz = Baz(self)

If this is correct, then running your code should produce the output 72 .