1// Copyright David Abrahams, Daniel Wallin 2003.
2// Distributed under the Boost Software License, Version 1.0.
3// (See accompanying file LICENSE_1_0.txt or copy at
4// http://www.boost.org/LICENSE_1_0.txt)
5
6#ifndef BOOST_PARAMETER_AUX_PACK_MAKE_ITEMS_HPP
7#define BOOST_PARAMETER_AUX_PACK_MAKE_ITEMS_HPP
8
9#include <boost/parameter/aux_/void.hpp>
10#include <boost/parameter/aux_/pack/item.hpp>
11#include <boost/parameter/config.hpp>
12
13#if defined(BOOST_PARAMETER_CAN_USE_MP11)
14#include <boost/mp11/utility.hpp>
15#include <type_traits>
16#else
17#include <boost/mpl/eval_if.hpp>
18#include <boost/mpl/identity.hpp>
19#include <boost/type_traits/is_same.hpp>
20#endif
21
22namespace boost { namespace parameter { namespace aux {
23
24 // Creates a item typelist.
25 template <typename Spec, typename Arg, typename Tail>
26#if defined(BOOST_PARAMETER_CAN_USE_MP11)
27 using make_items = ::boost::mp11::mp_if<
28 ::std::is_same<Arg,::boost::parameter::void_>
29 , ::boost::mp11::mp_identity< ::boost::parameter::void_>
30 , ::boost::parameter::aux::make_item<Spec,Arg,Tail>
31 >;
32#else
33 struct make_items
34 : ::boost::mpl::eval_if<
35 ::boost::is_same<Arg,::boost::parameter::void_>
36 , ::boost::mpl::identity< ::boost::parameter::void_>
37 , ::boost::parameter::aux::make_item<Spec,Arg,Tail>
38 >
39 {
40 };
41#endif
42}}} // namespace boost::parameter::aux
43
44#endif // include guard
45
46

source code of boost/libs/parameter/include/boost/parameter/aux_/pack/make_items.hpp