[dig1]

I think, everybody forgets one thing with C OO systems - no matter how primitive or advanced they are, they integrate much easily with languages that are sharing C libraries, than e.g. C++. Take, for example, GObject [1] from glib.

C++ had, for a long time, problem mapping classes and objects in python or ruby, and usually, that was done via C wrappers and hacks. In recent years, things are a little better thanks to clang, but there are still tons of template hacks and C workarounds if you want portable code between compilers. Even then, you often rely on compiler specific stuff.

Other languages are much worse, so the only solution, frequently, is to use a virtual machine, like JVM or .NET.

[1] https://en.wikipedia.org/wiki/GObject