Hi!

I'm using Intel C++, STLport 4.5.3 and the current CVS.

I can't get the simple example from the tutorial about virtual methods to work. 
I copied and pasted the example, but couldn't reproduce the correct behaviour in 
python:

// basic.cpp

#include <boost/python.hpp> 

using namespace boost::python;

struct Base
{
     virtual int f() = 0;
};

int call_f(Base& b) { return b.f(); }

struct BaseWrap : Base
{
     BaseWrap(PyObject* self_)
         : self(self_) {}
     int f() { return call_method<int> (self, "f"); }
     PyObject* self;
};


// Module ======================================================================
BOOST_PYTHON_MODULE(basic)
{
     class_<Base, BaseWrap, boost::noncopyable> ("Base", no_init)
         ;
     def("call_f", call_f);

}



 > >> from basic import *
 > >> class Derived(Base):
...     def f(self):
...             return 42
...
 > >> d = Derived()
Traceback (most recent call last):
   File "<stdin> ", line 1, in ?
RuntimeError: This class cannot be instantiated from Python
 > >>
 > >> # hmmm... let's override the __init__ method and see
 > >> # what happens
 > >> class Derived(Base):
...     def __init__(self): pass
...     def f(self): return 42
...
 > >> d = Derived()
 > >> call_f(d)
Traceback (most recent call last):
   File "<stdin> ", line 1, in ?
TypeError: bad argument type for built-in operation
 > >>

I remember using this example before, and it did work... has something changed 
since then?


Thanks,
Nicodemus.



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