我正在使用创建各种继承的c类
提升共享指针以引用它们,然后将这些共享包装起来
使用SWIG创建python类的指针.

我的问题如下：

> B是A的子类
> sA是指向A的共享指针
> sB是指向B的共享指针
> f(sA)是一个期望共享指向A的函数
>如果我将sB传递给f(),则会引发错误.
>此错误仅发生在python级别.
>在C级别,我可以毫无问题地将sB传递给f().

我有提升1.40和swig 1.3.40.

以下是将重现问题的5个文件的内容
有：

python setup.py build_ext --inplace
python test.py

swig_shared_ptr.h

#ifndef INCLUDED_SWIG_SHARED_PTR_H
#define INCLUDED_SWIG_SHARED_PTR_H

#include <boost/shared_ptr.hpp>

class Base {};

class Derived : public Base {};

typedef boost::shared_ptr<Base> base_sptr;
typedef boost::shared_ptr<Derived> derived_sptr;

void do_something (base_sptr bs);

base_sptr make_base();
derived_sptr make_derived();

#endif

swig_shared_ptr.cc

#include <iostream>
#include "swig_shared_ptr.h"

void do_something (base_sptr bs)
{
  std::cout << "Doing something." << std::endl;
}

base_sptr make_base() { return base_sptr(new Base ()); };
derived_sptr make_derived() { return derived_sptr(new Derived ()); };

swig_shared_ptr.i

%module(docstring="
Example module showing problems I am having with SWIG,shared pointers
and inheritance.
") swig_shared_ptr

%{
#include "swig_shared_ptr.h"
%}

%include <swig_shared_ptr.h>
%include <boost_shared_ptr.i>
%template(base_sptr) boost::shared_ptr<Base>;
%template(derived_sptr) boost::shared_ptr<Derived>;

setup.py

"""
setup.py file for swig_shared_ptr
"""

from distutils.core import setup,Extension

swig_shared_ptr_module = Extension('_swig_shared_ptr',include_dirs = ['/usr/include/boost'],sources=['swig_shared_ptr.i','swig_shared_ptr.cc'],)

setup (name = 'swig_shared_ptr',version = '0.1',author = "Ben",description = """Example showing problems I am having with SWIG,shared
                        pointers and inheritance.""",ext_modules = [swig_shared_ptr_module],py_modules = ["swig_shared_ptr"],)

test.py

import swig_shared_ptr as ssp

bs = ssp.make_base()
dr = ssp.make_derived()

# Works fine.
ssp.do_something(bs) 
# Fails with "TypeError: in method 'do_something',argument 1 of type 'base_sptr'"
ssp.do_something(dr)