A use for multiple inheritance?

Question

Can anyone think of any situation to use multiple inheritance? Every case I can think of can be solved by the method operator

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Answer 1

It is true that composition of an interface (Java or C# like) plus forwarding to a helper can emulate many of the common uses of multiple inheritance (notably mixins). However this is done at the cost of that forwarding code being repeated (and violating DRY).

MI does open a number of difficult areas, and more recently some language designers have taken decisions that the potential pitfalls of MI outweigh the benefits.

Similarly one can argue against generics (heterogeneous containers do work, loops can be replaced with (tail) recursion) and almost any other feature of programming languages. Just because it is possible to work without a feature does not mean that that feature is valueless or cannot help to effectively express solutions.

A rich diversity of languages, and language families makes it easier for us as developers to pick good tools that solve the business problem at hand. My toolbox contains many items I rarely use, but on those occasions I do not want to treat everything as a nail.