Common pointers and building in SIP4 (was: Dynamic casting in SWIG / python?)

Question

So, I am playing with Python, C ++ 0x and SWIG 2.0. I have a headline that looks like this:

#include <string>
#include <iostream>
#include <memory>
using namespace std;

struct Base {
  virtual string name();
  int foo;
  shared_ptr<Base> mine;
  Base(int);  
  virtual ~Base() {}
  virtual void doit(shared_ptr<Base> b) {
    cout << name() << " doing it to " << b->name() << endl;
    mine = b;
  }
  virtual shared_ptr<Base> getit() {
    return mine;
  }
};

struct Derived : Base {
  virtual string name();
  int bar;
  Derived(int, int);
};

Meanwhile, the interface file is as follows:

%module(directors="1") foo
%feature("director");

%include <std_string.i>

%include <std_shared_ptr.i>
%shared_ptr(Base)
%shared_ptr(Derived)

%{
#define SWIG_FILE_WITH_INIT
#include "foo.hpp"
%}

%include "foo.hpp"

My Python session is as follows:

>>> import foo
>>> b = foo.Base(42)
>>> d = foo.Derived(23,64)
>>> b.doit(d)
Base doing it to Derived 
>>> g = b.getit()
>>> g
<foo.Base; proxy of <Swig Object of type 'std::shared_ptr< Base > *' at 0x7f7bd1391930> >
>>> d
<foo.Derived; proxy of <Swig Object of type 'std::shared_ptr< Derived > *' at 0x7f7bd137ce10> >
>>> d == g
False
>>> d is g
False
>>> d.foo == g.foo
True
>>> d.bar
64
>>> g.bar
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'Base' object has no attribute 'bar'

I cannot figure out how to get the “original” proxy object here. Should I create a function for each base class to execute dynamic_pointer_cast? And if so, what of the Director subclasses are implemented in Python?

I feel that there is a switch or function that I can enable here to make SWIG execute the necessary lookup tables and produce the object that I want, but I have not found it yet.

(: , raw- , , SWIG dynamic_cast)

Update

( , ++, ) SWIG, SIP - Python?

# 2

SIP4 , , , . , . - SWIG, , :

• shared_ptr, raw-? , enable_shared_from_this .

• SIP4 ( Makefile distutils), Makefile?

Answer 1

() , SIP, , , ++ "Derived", Python - , raw-.

, , shared_ptr ( , %include <std_shared_ptr.i> SWIG).

, SIPs "build system" ( Makefile distutils) . " " - , , , / Hello World, . , " ", , python setup.py build_ext --inplace , , , , , , .