ceph/src/boost/boost/mp11/detail/mp_plus.hpp

   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
  14 namespace boost
  15 {
  16 namespace mp11
  17 {
  18
  19 // mp_plus
  20 namespace detail
  21 {
  22
  23 #if defined( BOOST_MP11_HAS_FOLD_EXPRESSIONS ) && !BOOST_MP11_WORKAROUND( BOOST_MP11_MSVC, < 1920 )
  24
  25 template<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
  33 template<class... T> struct mp_plus_impl;
  34
  35 template<> 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
  42 template<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
  48 template<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
  58 template<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
  64 template<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
  76 template<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