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diff --git a/boost/hana/zip_with.hpp b/boost/hana/zip_with.hpp
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+++ b/boost/hana/zip_with.hpp
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+/*!
+@file
+Defines `boost::hana::zip_with`.
+
+@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_ZIP_WITH_HPP
+#define BOOST_HANA_ZIP_WITH_HPP
+
+#include <boost/hana/fwd/zip_with.hpp>
+
+#include <boost/hana/at.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/fast_and.hpp>
+#include <boost/hana/length.hpp>
+
+#include <cstddef>
+#include <utility>
+
+
+BOOST_HANA_NAMESPACE_BEGIN
+    //! @cond
+    template <typename F, typename Xs, typename ...Ys>
+    constexpr auto zip_with_t::operator()(F&& f, Xs&& xs, Ys&& ...ys) const {
+    #ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
+        static_assert(detail::fast_and<
+            hana::Sequence<Xs>::value, hana::Sequence<Ys>::value...
+        >::value,
+        "hana::zip_with(f, xs, ys...) requires 'xs' and 'ys...' to be Sequences");
+    #endif
+
+        return zip_with_impl<typename hana::tag_of<Xs>::type>::apply(
+            static_cast<F&&>(f),
+            static_cast<Xs&&>(xs),
+            static_cast<Ys&&>(ys)...
+        );
+    }
+    //! @endcond
+
+    template <typename S>
+    struct zip_with_impl<S, when<Sequence<S>::value>> {
+        template <std::size_t N, typename F, typename ...Xs>
+        static constexpr decltype(auto) transverse(F&& f, Xs&& ...xs) {
+            return static_cast<F&&>(f)(hana::at_c<N>(static_cast<Xs&&>(xs))...);
+        }
+
+        template <std::size_t ...N, typename F, typename ...Xs>
+        static constexpr auto
+        zip_helper(std::index_sequence<N...>, F&& f, Xs&& ...xs) {
+            return hana::make<S>(transverse<N>(f, xs...)...);
+        }
+
+        template <typename F, typename X, typename ...Xs>
+        static constexpr auto
+        apply(F&& f, X&& x, Xs&& ...xs) {
+            constexpr std::size_t N = decltype(hana::length(x))::value;
+            return zip_helper(std::make_index_sequence<N>{},
+                              static_cast<F&&>(f),
+                              static_cast<X&&>(x), static_cast<Xs&&>(xs)...);
+        }
+    };
+BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_ZIP_WITH_HPP