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by ryao 298 days ago
If the kernel were written in C++, it would still be done the way it is done now. C++ does not allow unimplemented member functions and the ADTs currently used do. You can emulate that with multiple inheritance, but it is an inferior way of doing this.

As I said, these are NOT vtables. The fact that you and some others keep thinking of them as vtables misleads you into thinking that this can be done using the object oriented tools of C++. It cannot without major hacks and the result would be slower, harder to read and only something that a bureaucrat could like.
1 comments
1718627440 298 days ago
If the kernel were written in C++, it simply had the incentive to be less creative. Since it isn't it can be. It's just a restriction imposed by C++, not a restriction in the loosely defined paradigm of OOP.

> As I said, these are NOT vtables

Ok, you just define vtables differently then me. To me a vtable is a table of virtual functions that are used to implement polymorphic behaviour of objects. This applies to their usage in the kernel and the article. Feel free to introduce a new term for this. If your only distinction is whether these are created by a compiler, this is just a distinction I don't care about.

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ryao 298 days ago
The article author is wrong. It happens. Draw a vent diagram with two partially overlapping circles. You and the author are looking at the overlap and concluding the two are the same. They are not, given the stuff outside the overlap.

As for the one distinction you recognize and think is invalid, that distinction is given by the definition you found. You refuse to obey the definition you yourself quoted to settle matter elsewhere in the thread.

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1718627440 297 days ago
> As for the one distinction you recognize

It's not the only distinction I recognize, its the distinction you think matters here and that seams to be the basis for our disagreement.

This is the term (vtable, VMT) I got told in lectures to describe this pattern, you have yet not pointed me to a different term that you would recognize to be this, so in lack of a better term I will continue to use this.

As to why I think this distinction does not matter here, is because I perceive the compiler to be a tool that generates code which is controlled by the programmer. Thus the programmer in both cases creates codes with the same paradigm, they only differ in the tools used. We generally don't name things differently depending on which tools are used in the creation, except if they are created with a different intention.

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