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diff --git a/boost/hana/cycle.hpp b/boost/hana/cycle.hpp
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+++ b/boost/hana/cycle.hpp
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+/*!
+@file
+Defines `boost::hana::cycle`.
+
+@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_CYCLE_HPP
+#define BOOST_HANA_CYCLE_HPP
+
+#include <boost/hana/fwd/cycle.hpp>
+
+#include <boost/hana/at.hpp>
+#include <boost/hana/concat.hpp>
+#include <boost/hana/concept/integral_constant.hpp>
+#include <boost/hana/concept/monad_plus.hpp>
+#include <boost/hana/concept/sequence.hpp>
+#include <boost/hana/config.hpp>
+#include <boost/hana/core/dispatch.hpp>
+#include <boost/hana/core/make.hpp>
+#include <boost/hana/detail/array.hpp>
+#include <boost/hana/empty.hpp>
+#include <boost/hana/length.hpp>
+
+#include <cstddef>
+#include <utility>
+
+
+BOOST_HANA_NAMESPACE_BEGIN
+    //! @cond
+    template <typename Xs, typename N>
+    constexpr auto cycle_t::operator()(Xs&& xs, N const& n) const {
+        using M = typename hana::tag_of<Xs>::type;
+        using Cycle = BOOST_HANA_DISPATCH_IF(cycle_impl<M>,
+            hana::MonadPlus<M>::value
+        );
+
+    #ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
+        static_assert(hana::MonadPlus<M>::value,
+        "hana::cycle(xs, n) requires 'xs' to be a MonadPlus");
+
+        static_assert(hana::IntegralConstant<N>::value,
+        "hana::cycle(xs, n) requires 'n' to be an IntegralConstant");
+    #endif
+
+        static_assert(N::value >= 0,
+        "hana::cycle(xs, n) requires 'n' to be non-negative");
+
+        return Cycle::apply(static_cast<Xs&&>(xs), n);
+    }
+    //! @endcond
+
+    namespace detail {
+        template <typename M, std::size_t n, bool = n % 2 == 0>
+        struct cycle_helper;
+
+        template <typename M>
+        struct cycle_helper<M, 0, true> {
+            template <typename Xs>
+            static constexpr auto apply(Xs const&)
+            { return hana::empty<M>(); }
+        };
+
+        template <typename M, std::size_t n>
+        struct cycle_helper<M, n, true> {
+            template <typename Xs>
+            static constexpr auto apply(Xs const& xs)
+            { return cycle_helper<M, n/2>::apply(hana::concat(xs, xs)); }
+        };
+
+        template <typename M, std::size_t n>
+        struct cycle_helper<M, n, false> {
+            template <typename Xs>
+            static constexpr auto apply(Xs const& xs)
+            { return hana::concat(xs, cycle_helper<M, n-1>::apply(xs)); }
+        };
+    }
+
+    template <typename M, bool condition>
+    struct cycle_impl<M, when<condition>> : default_ {
+        template <typename Xs, typename N>
+        static constexpr auto apply(Xs const& xs, N const&) {
+            constexpr std::size_t n = N::value;
+            return detail::cycle_helper<M, n>::apply(xs);
+        }
+    };
+
+    namespace detail {
+        template <std::size_t N, std::size_t Len>
+        struct cycle_indices {
+            static constexpr auto compute_value() {
+                detail::array<std::size_t, N * Len> indices{};
+                // Avoid (incorrect) Clang warning about remainder by zero
+                // in the loop below.
+                std::size_t len = Len;
+                for (std::size_t i = 0; i < N * Len; ++i)
+                    indices[i] = i % len;
+                return indices;
+            }
+
+            static constexpr auto value = compute_value();
+        };
+    }
+
+    template <typename S>
+    struct cycle_impl<S, when<Sequence<S>::value>> {
+        template <typename Indices, typename Xs, std::size_t ...i>
+        static constexpr auto cycle_helper(Xs&& xs, std::index_sequence<i...>) {
+            constexpr auto indices = Indices::value;
+            (void)indices; // workaround GCC warning when sizeof...(i) == 0
+            return hana::make<S>(hana::at_c<indices[i]>(xs)...);
+        }
+
+        template <typename Xs, typename N>
+        static constexpr auto apply(Xs&& xs, N const&) {
+            constexpr std::size_t n = N::value;
+            constexpr std::size_t len = decltype(hana::length(xs))::value;
+            using Indices = detail::cycle_indices<n, len>;
+            return cycle_helper<Indices>(static_cast<Xs&&>(xs),
+                                         std::make_index_sequence<n * len>{});
+        }
+    };
+BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_CYCLE_HPP