* Juha Nieminen:
> [About circles and ellipses]
> The answer is that neither should be inherited from the other. This is
> because a circle and an ellipse are at the *same* conceptual level.

Generally, when that's the case, the person's concepts are flawed :-).

E.g., a constant circle Is-A constant ellipse (the general relationship
is a bit more complicated).

In C++ this can be expressed via interfaces or via implicit conversion.


[snip]
> The correct solution is to create a more abstract concept which is
> common to both circles and ellipses (and other similar drawing
> primitives), for example a "DrawingPrimitive" class, and inherit
> "Circle" and "Ellipse" from it.

Sorry, but there's no general "the" correct solution.


Cheers, & hth.,

- Alf

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