[C++-sig] Multiple-inheritance problem

[Piotr Jaroszyński]

Hello,

Seems that when one creates a Python class, which multiple-inherits from 
classes exposed by boost.python then it can be only converted(casted) to the 
first class in the inheritance list. Simple example code follows.

C++:
#include <boost/python.hpp>

namespace bp = boost::python;

struct A { };
struct B { };

void test_A(const A &) { }
void test_B(const B &) { }

BOOST_PYTHON_MODULE(multiple_inheritance)
{
    bp::def("test_A", &test_A);
    bp::def("test_B", &test_B);

    bp::class_<A>("A", bp::init<>());
    bp::class_<B>("B", bp::init<>());
}

Python:
class C(A, B):
    pass

test_A(C())
test_B(C())

And I get:
Traceback (most recent call last):
  File "./multiple_inheritance.py", line 10, in <module>
    test_B(C())
Boost.Python.ArgumentError: Python argument types in
    multiple_inheritance.test_B(C)
did not match C++ signature:
    test_B(B)

Am I missing something or is it a known problem? Any workaround if so?

-- 
Best Regards,
Piotr Jaroszyński