projects / ceph.git / blame
| Commit | Line | Data |
|---|---|---|
| 7c673cae FG |
1 | /*! |
| 2 | @file | |
| 3 | Defines `boost::hana::ordering`. | |
| 4 | ||
| b32b8144 | 5 | @copyright Louis Dionne 2013-2017 |
| 7c673cae FG |
6 | Distributed under the Boost Software License, Version 1.0. |
| 7 | (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt) | |
| 8 | */ | |
| 9 | ||
| 10 | #ifndef BOOST_HANA_ORDERING_HPP | |
| 11 | #define BOOST_HANA_ORDERING_HPP | |
| 12 | ||
| 13 | #include <boost/hana/fwd/ordering.hpp> | |
| 14 | ||
| 15 | #include <boost/hana/config.hpp> | |
| 16 | #include <boost/hana/detail/decay.hpp> | |
| 17 | #include <boost/hana/less.hpp> | |
| 18 | ||
| 19 | ||
| 20 | BOOST_HANA_NAMESPACE_BEGIN | |
| 21 | namespace detail { | |
| 22 | template <typename F> | |
| 23 | struct less_by { | |
| 24 | F f; | |
| 25 | ||
| 26 | template <typename X, typename Y> | |
| 27 | constexpr decltype(auto) operator()(X&& x, Y&& y) const& | |
| 28 | { return hana::less(f(static_cast<X&&>(x)), f(static_cast<Y&&>(y))); } | |
| 29 | ||
| 30 | template <typename X, typename Y> | |
| 31 | constexpr decltype(auto) operator()(X&& x, Y&& y) & | |
| 32 | { return hana::less(f(static_cast<X&&>(x)), f(static_cast<Y&&>(y))); } | |
| 33 | }; | |
| 34 | } | |
| 35 | ||
| 36 | //! @cond | |
| 37 | template <typename F> | |
| 38 | constexpr auto ordering_t::operator()(F&& f) const { | |
| 39 | return detail::less_by<typename detail::decay<F>::type>{static_cast<F&&>(f)}; | |
| 40 | } | |
| 41 | //! @endcond | |
| 42 | BOOST_HANA_NAMESPACE_END | |
| 43 | ||
| 44 | #endif // !BOOST_HANA_ORDERING_HPP |