1#ifndef BOOST_MP11_DETAIL_MP_PLUS_HPP_INCLUDED
2#define BOOST_MP11_DETAIL_MP_PLUS_HPP_INCLUDED
3
4// Copyright 2015 Peter Dimov.
5//
6// Distributed under the Boost Software License, Version 1.0.
7//
8// See accompanying file LICENSE_1_0.txt or copy at
9// http://www.boost.org/LICENSE_1_0.txt
10
11#include <boost/mp11/detail/config.hpp>
12#include <type_traits>
13
14namespace boost
15{
16namespace mp11
17{
18
19// mp_plus
20namespace detail
21{
22
23#if defined( BOOST_MP11_HAS_FOLD_EXPRESSIONS ) && !BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, < 1920 )
24
25template<class... T> struct mp_plus_impl
26{
27 static const auto _v = (T::value + ... + 0);
28 using type = std::integral_constant<typename std::remove_const<decltype(_v)>::type, _v>;
29};
30
31#else
32
33template<class... T> struct mp_plus_impl;
34
35template<> struct mp_plus_impl<>
36{
37 using type = std::integral_constant<int, 0>;
38};
39
40#if BOOST_MP11_WORKAROUND( BOOST_MP11_GCC, < 40800 )
41
42template<class T1, class... T> struct mp_plus_impl<T1, T...>
43{
44 static const decltype(T1::value + mp_plus_impl<T...>::type::value) _v = T1::value + mp_plus_impl<T...>::type::value;
45 using type = std::integral_constant<typename std::remove_const<decltype(_v)>::type, _v>;
46};
47
48template<class T1, class T2, class T3, class T4, class T5, class T6, class T7, class T8, class T9, class T10, class... T> struct mp_plus_impl<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T...>
49{
50 static const
51 decltype(T1::value + T2::value + T3::value + T4::value + T5::value + T6::value + T7::value + T8::value + T9::value + T10::value + mp_plus_impl<T...>::type::value)
52 _v = T1::value + T2::value + T3::value + T4::value + T5::value + T6::value + T7::value + T8::value + T9::value + T10::value + mp_plus_impl<T...>::type::value;
53 using type = std::integral_constant<typename std::remove_const<decltype(_v)>::type, _v>;
54};
55
56#else
57
58template<class T1, class... T> struct mp_plus_impl<T1, T...>
59{
60 static const auto _v = T1::value + mp_plus_impl<T...>::type::value;
61 using type = std::integral_constant<typename std::remove_const<decltype(_v)>::type, _v>;
62};
63
64template<class T1, class T2, class T3, class T4, class T5, class T6, class T7, class T8, class T9, class T10, class... T> struct mp_plus_impl<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T...>
65{
66 static const auto _v = T1::value + T2::value + T3::value + T4::value + T5::value + T6::value + T7::value + T8::value + T9::value + T10::value + mp_plus_impl<T...>::type::value;
67 using type = std::integral_constant<typename std::remove_const<decltype(_v)>::type, _v>;
68};
69
70#endif
71
72#endif
73
74} // namespace detail
75
76template<class... T> using mp_plus = typename detail::mp_plus_impl<T...>::type;
77
78} // namespace mp11
79} // namespace boost
80
81#endif // #ifndef BOOST_MP11_DETAIL_MP_PLUS_HPP_INCLUDED
82

source code of include/boost/mp11/detail/mp_plus.hpp