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diff --git a/boost/hana/monadic_compose.hpp b/boost/hana/monadic_compose.hpp
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+/*!
+@file
+Defines `boost::hana::monadic_compose`.
+
+@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_MONADIC_COMPOSE_HPP
+#define BOOST_HANA_MONADIC_COMPOSE_HPP
+
+#include <boost/hana/fwd/monadic_compose.hpp>
+
+#include <boost/hana/chain.hpp>
+#include <boost/hana/concept/monad.hpp>
+#include <boost/hana/config.hpp>
+#include <boost/hana/core/dispatch.hpp>
+#include <boost/hana/functional/partial.hpp>
+
+
+BOOST_HANA_NAMESPACE_BEGIN
+    namespace detail {
+        struct monadic_compose_helper {
+            template <typename F, typename G, typename X>
+            constexpr decltype(auto) operator()(F&& f, G&& g, X&& x) const {
+                using M = typename hana::tag_of<decltype(g(x))>::type;
+
+            #ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
+                static_assert(hana::Monad<M>::value,
+                "hana::monadic_compose(f, g) requires 'g' to return a monadic value");
+            #endif
+
+                return hana::chain(static_cast<G&&>(g)(static_cast<X&&>(x)),
+                                   static_cast<F&&>(f));
+            }
+        };
+    }
+
+    //! @cond
+    template <typename F, typename G>
+    constexpr auto monadic_compose_t::operator()(F&& f, G&& g) const {
+        return hana::partial(detail::monadic_compose_helper{},
+            static_cast<F&&>(f),
+            static_cast<G&&>(g)
+        );
+    }
+    //! @endcond
+BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_MONADIC_COMPOSE_HPP