#if !defined(BOOST_PP_IS_ITERATING)



// Copyright David Abrahams 2001.

// 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 VALUE_HOLDER_DWA20011215_HPP

#  define VALUE_HOLDER_DWA20011215_HPP 



#  include <boost/python/object/value_holder_fwd.hpp>



#  include <boost/python/instance_holder.hpp>

#  include <boost/python/type_id.hpp>

#  include <boost/python/wrapper.hpp>



#  include <boost/python/object/inheritance_query.hpp>

#  include <boost/python/object/forward.hpp>



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

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



#  include <boost/preprocessor/comma_if.hpp>

#  include <boost/preprocessor/enum_params.hpp>

#  include <boost/preprocessor/iterate.hpp>

#  include <boost/preprocessor/repeat.hpp>

#  include <boost/preprocessor/debug/line.hpp>



#  include <boost/preprocessor/repetition/enum_params.hpp>

#  include <boost/preprocessor/repetition/enum_binary_params.hpp>



#  include <boost/utility/addressof.hpp>



namespace boost { namespace python { namespace objects { 



#  if BOOST_WORKAROUND(__GNUC__, == 2)

#   define BOOST_PYTHON_UNFORWARD_LOCAL(z, n, _) BOOST_PP_COMMA_IF(n) (typename unforward<A##n>::type)objects::do_unforward(a##n,0)

#  else

#   define BOOST_PYTHON_UNFORWARD_LOCAL(z, n, _) BOOST_PP_COMMA_IF(n) objects::do_unforward(a##n,0)

#  endif 



template <class Value>

struct value_holder : instance_holder

{

    typedef Value held_type;

    typedef Value value_type;



    // Forward construction to the held object

#  define BOOST_PP_ITERATION_PARAMS_1 (4, (0, BOOST_PYTHON_MAX_ARITY, <boost/python/object/value_holder.hpp>, 1))

#  include BOOST_PP_ITERATE()



 private: // required holder implementation

    void* holds(type_info, bool null_ptr_only);

    

    template <class T>

    inline void* holds_wrapped(type_info dst_t, wrapper<T>*,T* p)

    {

        return python::type_id<T>() == dst_t ? p : 0;

    }

    

    inline void* holds_wrapped(type_info, ...)

    {

        return 0;

    }

 private: // data members

    Value m_held;

};



template <class Value, class Held>

struct value_holder_back_reference : instance_holder

{

    typedef Held held_type;

    typedef Value value_type;

    

    // Forward construction to the held object

#  define BOOST_PP_ITERATION_PARAMS_1 (4, (0, BOOST_PYTHON_MAX_ARITY, <boost/python/object/value_holder.hpp>, 2))

#  include BOOST_PP_ITERATE()



private: // required holder implementation

    void* holds(type_info, bool null_ptr_only);



 private: // data members

    Held m_held;

};



#  undef BOOST_PYTHON_UNFORWARD_LOCAL



template <class Value>

void* value_holder<Value>::holds(type_info dst_t, bool /*null_ptr_only*/)

{

    if (void* wrapped = holds_wrapped(dst_t, boost::addressof(m_held), boost::addressof(m_held)))

        return wrapped;

    

    type_info src_t = python::type_id<Value>();

    return src_t == dst_t ? boost::addressof(m_held)

        : find_static_type(boost::addressof(m_held), src_t, dst_t);

}



template <class Value, class Held>

void* value_holder_back_reference<Value,Held>::holds(

    type_info dst_t, bool /*null_ptr_only*/)

{

    type_info src_t = python::type_id<Value>();

    Value* x = &m_held;

    

    if (dst_t == src_t)

        return x;

    else if (dst_t == python::type_id<Held>())

        return &m_held;

    else

        return find_static_type(x, src_t, dst_t);

}



}}} // namespace boost::python::objects



# endif // VALUE_HOLDER_DWA20011215_HPP



// --------------- value_holder ---------------



#elif BOOST_PP_ITERATION_DEPTH() == 1 && BOOST_PP_ITERATION_FLAGS() == 1

# if !(BOOST_WORKAROUND(__MWERKS__, > 0x3100)                      \

        && BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3201)))

#  line BOOST_PP_LINE(__LINE__, value_holder.hpp(value_holder))

# endif



# define N BOOST_PP_ITERATION()



# if (N != 0)

    template <BOOST_PP_ENUM_PARAMS_Z(1, N, class A)>

# endif

    value_holder(

      PyObject* self BOOST_PP_COMMA_IF(N) BOOST_PP_ENUM_BINARY_PARAMS_Z(1, N, A, a))

        : m_held(

            BOOST_PP_REPEAT_1ST(N, BOOST_PYTHON_UNFORWARD_LOCAL, nil)

            )

    {

        python::detail::initialize_wrapper(self, boost::addressof(this->m_held));

    }



# undef N



// --------------- value_holder_back_reference ---------------



#elif BOOST_PP_ITERATION_DEPTH() == 1 && BOOST_PP_ITERATION_FLAGS() == 2

# if !(BOOST_WORKAROUND(__MWERKS__, > 0x3100)                      \

        && BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3201)))

#  line BOOST_PP_LINE(__LINE__, value_holder.hpp(value_holder_back_reference))

# endif



# define N BOOST_PP_ITERATION()



# if (N != 0)

    template <BOOST_PP_ENUM_PARAMS_Z(1, N, class A)>

# endif

    value_holder_back_reference(

        PyObject* p BOOST_PP_COMMA_IF(N) BOOST_PP_ENUM_BINARY_PARAMS_Z(1, N, A, a))

        : m_held(

            p BOOST_PP_COMMA_IF(N)

            BOOST_PP_REPEAT_1ST(N, BOOST_PYTHON_UNFORWARD_LOCAL, nil)

            )

    {

    }



# undef N



#endif

