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diff --git a/boost/hana/unfold_right.hpp b/boost/hana/unfold_right.hpp
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+/*!
+@file
+Defines `boost::hana::unfold_right`.
+
+@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_UNFOLD_RIGHT_HPP
+#define BOOST_HANA_UNFOLD_RIGHT_HPP
+
+#include <boost/hana/fwd/unfold_right.hpp>
+
+#include <boost/hana/concept/sequence.hpp>
+#include <boost/hana/config.hpp>
+#include <boost/hana/core/dispatch.hpp>
+#include <boost/hana/empty.hpp>
+#include <boost/hana/first.hpp>
+#include <boost/hana/functional/partial.hpp>
+#include <boost/hana/optional.hpp>
+#include <boost/hana/prepend.hpp>
+#include <boost/hana/second.hpp>
+
+
+BOOST_HANA_NAMESPACE_BEGIN
+    //! @cond
+    template <typename S>
+    struct unfold_right_t {
+    #ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
+        static_assert(hana::Sequence<S>::value,
+        "hana::unfold_right<S> requires 'S' to be a Sequence");
+    #endif
+
+        template <typename State, typename F>
+        constexpr auto operator()(State&& state, F&& f) const {
+            return unfold_right_impl<S>::apply(
+                static_cast<State&&>(state),
+                static_cast<F&&>(f)
+            );
+        }
+    };
+    //! @endcond
+
+    template <typename S, bool condition>
+    struct unfold_right_impl<S, when<condition>> : default_ {
+        struct unfold_right_helper {
+            template <typename F, typename P>
+            constexpr auto operator()(F&& f, P&& p) const {
+                return hana::prepend(
+                    unfold_right_impl::apply(
+                        hana::second(static_cast<P&&>(p)),
+                        static_cast<F&&>(f)
+                    ),
+                    hana::first(static_cast<P&&>(p))
+                );
+            }
+        };
+
+        template <typename Init, typename F>
+        static constexpr auto apply(Init&& init, F&& f) {
+            decltype(auto) elt = f(static_cast<Init&&>(init));
+            return hana::maybe(hana::empty<S>(),
+                hana::partial(unfold_right_helper{}, static_cast<F&&>(f)),
+                static_cast<decltype(elt)&&>(elt)
+            );
+        }
+    };
+BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_UNFOLD_RIGHT_HPP