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by Pitarou 3342 days ago
Take a class C.

Alice extends class C with class A, which implements function a.

Bob extends class C with class B, which implements function b.

I have both Alice’s and Bob’s code, and I want to use both a and b. How can I do it?

Of course, there are ways to do it – notably multiple inheritance, if your language supports it – but the point is, in a functional language, this question never even arises. You just import the function definitions and use them, without ever having to think about the mechanics of it.

By the way, I’m not saying that this necessarily makes functional languages better (although I do tend to prefer them). I’m just pointing out that the difference is real.
1 comments
horrido 3342 days ago
Inheritance is not a strict requirement of OOP. In OOP, you can always use composition, in which case the question also never arises.

Inheritance is there if you need it. It's an available option.

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BoiledCabbage 3342 days ago
Yes, but in common discussion, noone when talking about OOP is referring to inheritence-less OOP. No common programming language uses it, few to no programmers practice it. OOP/w inheritance is the default item being discussed.
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horrido 3342 days ago
And why is "common discussion" technically relevant? This is not a fault of OOP but of education.
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BoiledCabbage 3341 days ago
You're talking about about OOP-B, everyone here is talking about OOP-A. OOP-B isn't really a part of what's being discussed.

Anyone can bring it up, but "education" isn't relevant here. It's not what was discussed in the article, or the comments.

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nailer 3339 days ago
As neither of you, I'm talking about OOP. Nobody's limiting the discussion to composition or inheritance. Otherwise we'd be talking about how 'inheritance sucks' rather than 'OOP sucks'.
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dllthomas 3342 days ago
> in which case the question also never arises.

I'm not sure I see that.

If class A and B wrap a C by composition and expose, respectively, `a` and `b`, then I still very much have the choice of which I'm building. Perhaps less so if they wrap a C by reference, so the C can be reused (it's too late at night to be sure I've thought it all the way through).

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