Chris@16: // Copyright David Abrahams 2002.
Chris@16: // Distributed under the Boost Software License, Version 1.0. (See
Chris@16: // accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: #ifndef BACK_REFERENCE_DWA2002510_HPP
Chris@16: # define BACK_REFERENCE_DWA2002510_HPP
Chris@16: 
Chris@16: # include <boost/python/detail/prefix.hpp>
Chris@16: 
Chris@16: # include <boost/python/object_fwd.hpp>
Chris@16: # include <boost/python/detail/dependent.hpp>
Chris@16: # include <boost/python/detail/raw_pyobject.hpp>
Chris@16: 
Chris@16: namespace boost { namespace python { 
Chris@16: 
Chris@16: template <class T>
Chris@16: struct back_reference
Chris@16: {
Chris@16:  private: // types
Chris@16:     typedef typename detail::dependent<object,T>::type source_t;
Chris@16:  public:
Chris@16:     typedef T type;
Chris@16:     
Chris@16:     back_reference(PyObject*, T);
Chris@16:     source_t const& source() const;
Chris@16:     T get() const;
Chris@16:  private:
Chris@16:     source_t m_source;
Chris@16:     T m_value;
Chris@16: };
Chris@16: 
Chris@16: # ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
Chris@16: template<typename T>
Chris@16: class is_back_reference
Chris@16: {
Chris@16:  public:
Chris@16:     BOOST_STATIC_CONSTANT(bool, value = false); 
Chris@16: };
Chris@16: 
Chris@16: template<typename T>
Chris@16: class is_back_reference<back_reference<T> >
Chris@16: {
Chris@16:  public:
Chris@16:     BOOST_STATIC_CONSTANT(bool, value = true);
Chris@16: };
Chris@16: 
Chris@16: # else // no partial specialization
Chris@16: 
Chris@16: }} // namespace boost::python
Chris@16: 
Chris@16: #include <boost/type.hpp>
Chris@16: 
Chris@16: namespace boost { namespace python {
Chris@16: 
Chris@16: namespace detail
Chris@16: {
Chris@16:   typedef char (&yes_back_reference_t)[1];
Chris@16:   typedef char (&no_back_reference_t)[2];
Chris@16:       
Chris@16:   no_back_reference_t is_back_reference_test(...);
Chris@16: 
Chris@16:   template<typename T>
Chris@16:   yes_back_reference_t is_back_reference_test(boost::type< back_reference<T> >);
Chris@16: }
Chris@16: 
Chris@16: template<typename T>
Chris@16: class is_back_reference
Chris@16: {
Chris@16:  public:
Chris@16:     BOOST_STATIC_CONSTANT(
Chris@16:         bool, value = (
Chris@16:             sizeof(detail::is_back_reference_test(boost::type<T>()))
Chris@16:             == sizeof(detail::yes_back_reference_t)));
Chris@16: };
Chris@16: 
Chris@16: # endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
Chris@16: 
Chris@16: //
Chris@16: // implementations
Chris@16: //
Chris@16: template <class T>
Chris@16: back_reference<T>::back_reference(PyObject* p, T x)
Chris@16:     : m_source(detail::borrowed_reference(p))
Chris@16:       , m_value(x)
Chris@16: {
Chris@16: }
Chris@16: 
Chris@16: template <class T>
Chris@16: typename back_reference<T>::source_t const& back_reference<T>::source() const
Chris@16: {
Chris@16:     return m_source;
Chris@16: }
Chris@16: 
Chris@16: template <class T>
Chris@16: T back_reference<T>::get() const
Chris@16: {
Chris@16:     return m_value;
Chris@16: }
Chris@16: 
Chris@16: }} // namespace boost::python
Chris@16: 
Chris@16: #endif // BACK_REFERENCE_DWA2002510_HPP