1 // Copyright David Abrahams 2002. 2 // Distributed under the Boost Software License, Version 1.0. (See 3 // accompanying file LICENSE_1_0.txt or copy at 4 // http://www.boost.org/LICENSE_1_0.txt) 5 #ifndef REFERENCE_EXISTING_OBJECT_DWA200222_HPP 6 # define REFERENCE_EXISTING_OBJECT_DWA200222_HPP 7 8 # include <boost/python/detail/prefix.hpp> 9 # include <boost/python/detail/indirect_traits.hpp> 10 # include <boost/mpl/if.hpp> 11 # include <boost/python/to_python_indirect.hpp> 12 # include <boost/python/detail/type_traits.hpp> 13 14 namespace boost { namespace python { 15 16 namespace detail 17 { 18 template <class R> 19 struct reference_existing_object_requires_a_pointer_or_reference_return_type 20 # if defined(__GNUC__) || defined(__EDG__) 21 {} 22 # endif 23 ; 24 } 25 26 template <class T> struct to_python_value; 27 28 struct reference_existing_object 29 { 30 template <class T> 31 struct apply 32 { 33 BOOST_STATIC_CONSTANT( 34 bool, ok = detail::is_pointer<T>::value || detail::is_reference<T>::value); 35 36 typedef typename mpl::if_c< 37 ok 38 , to_python_indirect<T, detail::make_reference_holder> 39 , detail::reference_existing_object_requires_a_pointer_or_reference_return_type<T> 40 >::type type; 41 }; 42 }; 43 44 }} // namespace boost::python 45 46 #endif // REFERENCE_EXISTING_OBJECT_DWA200222_HPP 47