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 BASES_DWA2002321_HPP 6 # define BASES_DWA2002321_HPP 7 8 # include <boost/python/detail/prefix.hpp> 9 # include <boost/python/detail/type_list.hpp> 10 # include <boost/python/detail/type_traits.hpp> 11 # include <boost/mpl/if.hpp> 12 # include <boost/mpl/bool.hpp> 13 # include <boost/preprocessor/enum_params_with_a_default.hpp> 14 # include <boost/preprocessor/enum_params.hpp> 15 16 namespace boost { namespace python { 17 18 # define BOOST_PYTHON_BASE_PARAMS BOOST_PP_ENUM_PARAMS_Z(1, BOOST_PYTHON_MAX_BASES, Base) 19 20 // A type list for specifying bases 21 template < BOOST_PP_ENUM_PARAMS_WITH_A_DEFAULT(BOOST_PYTHON_MAX_BASES, typename Base, mpl::void_) > 22 struct bases : detail::type_list< BOOST_PYTHON_BASE_PARAMS >::type 23 {}; 24 25 namespace detail 26 { 27 template <class T> struct specifies_bases 28 : mpl::false_ 29 { 30 }; 31 32 template < BOOST_PP_ENUM_PARAMS_Z(1, BOOST_PYTHON_MAX_BASES, class Base) > 33 struct specifies_bases< bases< BOOST_PYTHON_BASE_PARAMS > > 34 : mpl::true_ 35 { 36 }; 37 template <class T, class Prev = bases<> > 38 struct select_bases 39 : mpl::if_< 40 specifies_bases<T> 41 , T 42 , Prev 43 > 44 { 45 }; 46 } 47 # undef BOOST_PYTHON_BASE_PARAMS 48 }} // namespace boost::python 49 50 #endif // BASES_DWA2002321_HPP 51