Worked but I'm not 100% sure why. Can someone help me check if i have the right thought process?

Question

I like trying to get have a fundamentally understanding of things, however OOP has begun to elude me especially when making emulating the built-ins.

Biggest questions Do I have to even mention init if want to modify the len functionality of the list class? I looked at other people's sol'n to this challenge the answer appears to be no, but why is that?

Less big questions I don't think I understand the required arguments of init in general (besides self). LIke what exactly do have to include? Why did I have to specify that value was a list variable to pass?

I know super().init() was unnecessary b/c i tried the challenge again without it (hence the #), but I again don't think I know what exactly it does in this context.

I passed this code challenge however I had some superfluous code (b/c i really didn't understand what needs to be there vs. what is optional)

frustration.py

class Liar(list):
    def __init__(self, value = [], *args, **kwargs):
        #super().__init__()
        self.value = value
    def __len__(self):
        return len(self.value) + 3

Answer 1 · 2017-05-26T07:42:54Z

May 26, 2017 7:42am

You don't need to redefine init because you don't need to change the functionality of init. If you don't redefine init, Liar will use the init it inherited from list.

I'm guessing the reason you needed a default value for value is because one of the tests is an empty list created with list(), so an error occured because value wasn't defined.

super().__init__() just initializes the list as if it were empty.

Here's a simpler way to pass the challenge:

class Liar(list):
    def __len__(self):
        return super().__len__() + 3

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Paul Ehizuelen Jr.

Paul Ehizuelen Jr.

Worked but I'm not 100% sure why. Can someone help me check if i have the right thought process?

1 Answer

James Shi

James Shi