ceph/src/boost/libs/python/include/boost/python/reference_existing_object.hpp

   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/type_traits/composite_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 = is_pointer<T>::value || 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