[C++-sig] Virtual Methods + default arguments

[Bruno da Silva de Oliveira]

Hi!

Is it possible to indicate default arguments for virtual methods, using 
the BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS macro?

I have this code:

    struct X
    {
        virtual void f(int x = 10, char c = 'a')
        {
           std::cout << x << ", " << c << std::endl;
        }
    };

    void call_f(X& x)
    {
        x.f();
    }


    BOOST_PYTHON_MEMBER_FUNCTION_OVERLOADS(f_overloads, f, 0, 2)

    struct XWrap: X
    {
        XWrap(PyObject* self_): self(self_) {}
        XWrap(PyObject* self_, const X&): self(self_) {}
        PyObject* self;
   
        void f(int x = 10, char c = 'a')
        {
            call_method<void>(self, "f", x, c);
        }
   
        void default_f(int x = 10, char c = 'a')
        {
            X::f(x, c);
        }
    };

    BOOST_PYTHON_MODULE(test)
    {   
        def("call_f", &call_f);
        class_< X, XWrap >("X")       
            .def("f", &X::f, &XWrap::default_f, f_overloads())
        ;
    }

But this does not compile. Here's the first line of the output of the 
compiler:

    
D:\Programming\Libraries\boost-cvs\boost\boost/python/detail/caller.hpp(53): 
error: class "f_overloads" has no member "result_converter"

So I tried to change the class_ definition to this:
   
    class_< X, XWrap >("X")       
        .def("f", &X::f, &XWrap::default_f)
        .def("f", &X::f, f_overloads())
    ;

It compiles fine, but in python:

 >>> from test import *
 >>> x = X()
 >>> x.f(10, 'c')
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
RuntimeError: unidentifiable C++ exception
 >>>

I also tried to change the second .def to:

   .def("f", &XWrap::f, f_overloads())

and:

   .def("f", &XWrap::default_f, f_overloads())

But with the same results.

So, is it possible to have virtual methods with default arguments? If 
so, how? Any pointer would be greatly appreciated.

Thanks in advance,
Nicodemus.