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diff --git a/src/boost/libs/hana/example/cppcon_2014/matrix/ring.hpp b/src/boost/libs/hana/example/cppcon_2014/matrix/ring.hpp
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+++ b/src/boost/libs/hana/example/cppcon_2014/matrix/ring.hpp
@@ -0,0 +1,62 @@
+// Copyright Louis Dionne 2013-2017
+// 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_EXAMPLE_CPPCON_2014_MATRIX_RING_HPP
+#define BOOST_HANA_EXAMPLE_CPPCON_2014_MATRIX_RING_HPP
+
+#include "matrix.hpp"
+
+#include <boost/hana/equal.hpp>
+#include <boost/hana/fwd/mult.hpp>
+#include <boost/hana/fwd/one.hpp>
+#include <boost/hana/if.hpp>
+#include <boost/hana/integral_constant.hpp>
+#include <boost/hana/range.hpp>
+#include <boost/hana/replicate.hpp>
+#include <boost/hana/transform.hpp>
+#include <boost/hana/tuple.hpp>
+#include <boost/hana/unpack.hpp>
+#include <boost/hana/zip_with.hpp>
+
+#include <utility>
+
+
+namespace boost { namespace hana {
+    template <unsigned R1, unsigned C1, unsigned R2, unsigned C2>
+    struct mult_impl<cppcon::Matrix<R1, C1>, cppcon::Matrix<R2, C2>> {
+        template <typename M1, typename M2>
+        static constexpr decltype(auto) apply(M1&& m1, M2&& m2) {
+            static_assert(C1 == R2,
+                "wrong dimensions for matrix multiplication");
+            auto cols = cppcon::columns(std::forward<M2>(m2));
+            return unpack(
+                transform(cppcon::rows(std::forward<M1>(m1)),
+                    [&](auto&& row) -> decltype(auto) {
+                        return zip_with(cppcon::detail::tuple_scalar_product,
+                            replicate<tuple_tag>(std::forward<decltype(row)>(row), uint_c<R1>),
+                            cols
+                        );
+                    }
+                ),
+                cppcon::matrix
+            );
+        }
+    };
+
+    template <unsigned R, unsigned C>
+    struct one_impl<cppcon::Matrix<R, C>> {
+        static constexpr decltype(auto) apply() {
+            return unpack(range_c<unsigned, 0, R>, [](auto ...n) {
+                return unpack(range_c<unsigned, 0, C>, [=](auto ...m) {
+                    auto row = [=](auto n) {
+                        return cppcon::row(if_(n == m, int_c<1>, int_c<0>)...);
+                    };
+                    return cppcon::matrix(row(n)...);
+                });
+            });
+        }
+    };
+}}
+
+#endif // !BOOST_HANA_EXAMPLE_CPPCON_2014_MATRIX_RING_HPP