// Copyright David Abrahams 2002.

 // Distributed under the Boost Software License, Version 1.0. (See

 // accompanying file LICENSE_1_0.txt or copy at

 // http://www.boost.org/LICENSE_1_0.txt)

 #ifndef INSTANCE_DWA200295_HPP

 # define INSTANCE_DWA200295_HPP

 # include <boost/python/detail/prefix.hpp>

 # include <boost/type_traits/alignment_traits.hpp>

 # include <cstddef>

 namespace boost { namespace python

 {

   struct BOOST_PYTHON_DECL_FORWARD instance_holder;

 }} // namespace boost::python

 namespace boost { namespace python { namespace objects { 

 // Each extension instance will be one of these

 template <class Data = char>

 struct instance

 {

     PyObject_VAR_HEAD

     PyObject* dict;

     PyObject* weakrefs; 

     instance_holder* objects;

     typedef typename type_with_alignment<

         ::boost::alignment_of<Data>::value

     >::type align_t;

     union

     {

         align_t align;

         char bytes[sizeof(Data)];

     } storage;

 };

 template <class Data>

 struct additional_instance_size

 {

     typedef instance<Data> instance_data;

     typedef instance<char> instance_char;

     BOOST_STATIC_CONSTANT(

         std::size_t, value = sizeof(instance_data)

                            - BOOST_PYTHON_OFFSETOF(instance_char,storage));

 };

 }}} // namespace boost::python::object

 #endif // INSTANCE_DWA200295_HPP