/*! @file Defines operators for Monads. @copyright Louis Dionne 2013-2016 Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt) */ #ifndef BOOST_HANA_DETAIL_OPERATORS_MONAD_HPP #define BOOST_HANA_DETAIL_OPERATORS_MONAD_HPP #include <boost/hana/config.hpp> #include <boost/hana/core/tag_of.hpp> #include <boost/hana/fwd/chain.hpp> #include <type_traits> BOOST_HANA_NAMESPACE_BEGIN namespace detail { template <typename Tag> struct monad_operators { static constexpr bool value = false; }; namespace operators { template <typename Xs, typename F, typename = typename std::enable_if< detail::monad_operators<typename hana::tag_of<Xs>::type>::value >::type> constexpr auto operator|(Xs&& xs, F&& f) { return hana::chain(static_cast<Xs&&>(xs), static_cast<F&&>(f)); } } // end namespace operators } BOOST_HANA_NAMESPACE_END #endif // !BOOST_HANA_DETAIL_OPERATORS_MONAD_HPP