[Swig-user] a problem with method-specific directors

[<pp...@fy...>]

Dear All,

I am trying to use directors to be able to overwrite
virtual methods of the underlying C++ library in Python.
When creating the director classes for all classes and
all virtual methods, everything works as expected, but I 
am having trouble if I try to limit the creation of the
directors to only those methods for which it is necessary.
To illustrate the problem, I have created the following
example with C++ header "clib.h" as

class Base
{
 public:
  void call();
  virtual void method();
};

class CDerived : public Base
{
 public:
  void method();
};

the corresponding implementation "clib.cpp" as

#include "clib.h"
#include <iostream>
using namespace std;

void Base::call()
{
  method();
}

void Base::method()
{
  cout << "Base::method" << endl;
}

void CDerived::method()
{
  cout << "CDerived::method" << endl;
}   

the interface file "clib.i" as

%module(directors="1") clib;

%feature("director");

%{
#include "clib.h"
%}

class Base
{
 public:
  void call();
  virtual void method();
};

class CDerived : public Base
{
 public:
  void method();
};

and a Python code "test.py" to try the bindings as

from clib import *

class PythonDerived(CDerived):
    def method(self):
        print "PythonDerived::method"

pd = PythonDerived()
pd.call()

When running the code as above, it prints
PythonDerived::method
as expected. However, if a change the line

%feature("director");

in the interface file to either one of the following 
(as instructed in section 26.5.1 of the manual)

%feature("director") Base::method;
%feature("director") CDerived::method;

or both, test.py prints
CDerived::method
which is wrong since I would like to have the 
overwritten method in PythonDerived to be called. 

What am I doing wrong here or what's going on?

I am using swig 1.3.27, python 2.3.5 and gcc 4.0.3
(all as distributed by Debian) and I create the wrappers
and compile them with the following command sequence

g++ -c -o clib.o clib.cpp
swig -c++ -python clib.i
g++ -c -o clib_wrap.o clib_wrap.cxx -I/usr/include/python2.3
g++ -shared -o _clib.so clib.o clib_wrap.o

Best Regards, 
Matti

-- 
Matti Peltomaki, Graduate Student
Laboratory of Physics 
Helsinki University of Technology
040 7576977, room Y308B