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diff --git a/boost/hana/lexicographical_compare.hpp b/boost/hana/lexicographical_compare.hpp
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+++ b/boost/hana/lexicographical_compare.hpp
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+/*!
+@file
+Defines `boost::hana::lexicographical_compare`.
+
+@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_LEXICOGRAPHICAL_COMPARE_HPP
+#define BOOST_HANA_LEXICOGRAPHICAL_COMPARE_HPP
+
+#include <boost/hana/fwd/lexicographical_compare.hpp>
+
+#include <boost/hana/bool.hpp>
+#include <boost/hana/concept/iterable.hpp>
+#include <boost/hana/config.hpp>
+#include <boost/hana/core/dispatch.hpp>
+#include <boost/hana/drop_front.hpp>
+#include <boost/hana/front.hpp>
+#include <boost/hana/if.hpp>
+#include <boost/hana/is_empty.hpp>
+#include <boost/hana/less.hpp>
+
+
+BOOST_HANA_NAMESPACE_BEGIN
+    //! @cond
+    template <typename Xs, typename Ys>
+    constexpr auto lexicographical_compare_t::operator()(Xs const& xs, Ys const& ys) const {
+        return hana::lexicographical_compare(xs, ys, hana::less);
+    }
+
+    template <typename Xs, typename Ys, typename Pred>
+    constexpr auto lexicographical_compare_t::operator()(Xs const& xs, Ys const& ys, Pred const& pred) const {
+        using It1 = typename hana::tag_of<Xs>::type;
+        using It2 = typename hana::tag_of<Ys>::type;
+        using LexicographicalCompare = BOOST_HANA_DISPATCH_IF(
+            lexicographical_compare_impl<It1>,
+            hana::Iterable<It1>::value &&
+            hana::Iterable<It2>::value
+        );
+
+    #ifndef BOOST_HANA_CONFIG_DISABLE_CONCEPT_CHECKS
+        static_assert(hana::Iterable<It1>::value,
+        "hana::lexicographical_compare(xs, ys, pred) requires 'xs' to be Iterable");
+
+        static_assert(hana::Iterable<It2>::value,
+        "hana::lexicographical_compare(xs, ys, pred) requires 'ys' to be Iterable");
+    #endif
+
+        return LexicographicalCompare::apply(xs, ys, pred);
+    }
+    //! @endcond
+
+    template <typename It, bool condition>
+    struct lexicographical_compare_impl<It, when<condition>> : default_ {
+        template <typename Xs, typename Ys, typename Pred>
+        static constexpr auto
+        helper2(Xs const&, Ys const&, Pred const&, hana::true_)
+        { return hana::false_c; }
+
+        template <typename Xs, typename Ys, typename Pred>
+        static constexpr auto
+        helper2(Xs const& xs, Ys const& ys, Pred const& pred, hana::false_)
+        { return apply(hana::drop_front(xs), hana::drop_front(ys), pred); }
+
+        template <typename Xs, typename Ys, typename Pred>
+        static constexpr auto
+        helper2(Xs const& xs, Ys const& ys, Pred const& pred, bool is_greater)
+        { return is_greater ? false : apply(hana::drop_front(xs), hana::drop_front(ys), pred); }
+
+
+        template <typename Xs, typename Ys, typename Pred>
+        static constexpr auto
+        helper1(Xs const&, Ys const&, Pred const&, hana::true_)
+        { return hana::true_c; }
+
+        template <typename Xs, typename Ys, typename Pred>
+        static constexpr auto
+        helper1(Xs const& xs, Ys const& ys, Pred const& pred, hana::false_)
+        { return helper2(xs, ys, pred, hana::if_(pred(hana::front(ys), hana::front(xs)), hana::true_c, hana::false_c)); }
+
+        template <typename Xs, typename Ys, typename Pred>
+        static constexpr auto
+        helper1(Xs const& xs, Ys const& ys, Pred const& pred, bool is_less)
+        { return is_less ? true : helper2(xs, ys, pred, hana::if_(pred(hana::front(ys), hana::front(xs)), hana::true_c, hana::false_c)); }
+
+
+        template <typename Xs, typename Ys, typename Pred>
+        static constexpr auto
+        helper(Xs const&, Ys const& ys, Pred const&, hana::true_)
+        { return hana::not_(hana::is_empty(ys)); }
+
+        template <typename Xs, typename Ys, typename Pred>
+        static constexpr auto
+        helper(Xs const& xs, Ys const& ys, Pred const& pred, hana::false_)
+        { return helper1(xs, ys, pred, hana::if_(pred(hana::front(xs), hana::front(ys)), hana::true_c, hana::false_c)); }
+
+
+        template <typename Xs, typename Ys, typename Pred>
+        static constexpr auto apply(Xs const& xs, Ys const& ys, Pred const& pred) {
+            return helper(xs, ys, pred, hana::bool_c<
+                decltype(hana::is_empty(xs))::value ||
+                decltype(hana::is_empty(ys))::value
+            >);
+        }
+    };
+BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_LEXICOGRAPHICAL_COMPARE_HPP