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diff --git a/src/boost/libs/hana/example/cppcon_2014/matrix/det.hpp b/src/boost/libs/hana/example/cppcon_2014/matrix/det.hpp
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+++ b/src/boost/libs/hana/example/cppcon_2014/matrix/det.hpp
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+// 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_DET_HPP
+#define BOOST_HANA_EXAMPLE_CPPCON_2014_MATRIX_DET_HPP
+
+#include <boost/hana/equal.hpp>
+#include <boost/hana/eval_if.hpp>
+#include <boost/hana/front.hpp>
+#include <boost/hana/functional/always.hpp>
+#include <boost/hana/functional/fix.hpp>
+#include <boost/hana/functional/flip.hpp>
+#include <boost/hana/functional/on.hpp>
+#include <boost/hana/functional/partial.hpp>
+#include <boost/hana/integral_constant.hpp>
+#include <boost/hana/plus.hpp>
+#include <boost/hana/power.hpp>
+#include <boost/hana/range.hpp>
+#include <boost/hana/remove_at.hpp>
+#include <boost/hana/transform.hpp>
+#include <boost/hana/tuple.hpp>
+#include <boost/hana/unpack.hpp>
+
+#include <utility>
+
+#include "matrix.hpp"
+
+
+namespace cppcon {
+    namespace hana = boost::hana;
+    auto det = hana::fix([](auto det, auto&& m) -> decltype(auto) {
+        auto matrix_minor = [=](auto&& m, auto i, auto j) -> decltype(auto) {
+            return det(hana::unpack(
+                hana::transform(
+                    hana::remove_at(rows(std::forward<decltype(m)>(m)), i),
+                    hana::partial(hana::flip(hana::remove_at), j)
+                ),
+                matrix
+            ));
+        };
+
+        auto cofactor = [=](auto&& m, auto i, auto j) {
+            return hana::power(hana::int_c<-1>, hana::plus(i, j)) *
+                    matrix_minor(std::forward<decltype(m)>(m), i, j);
+        };
+
+        return hana::eval_if(m.size() == hana::size_c<1>,
+            hana::always(m.at(hana::size_c<0>, hana::size_c<0>)),
+            [=](auto _) {
+                auto cofactors_1st_row = hana::unpack(_(hana::make_range)(hana::size_c<0>, m.ncolumns()),
+                    hana::on(hana::make_tuple, hana::partial(cofactor, m, hana::size_c<0>))
+                );
+                return detail::tuple_scalar_product(hana::front(rows(m)), cofactors_1st_row);
+            }
+        );
+    });
+} // end namespace cppcon
+
+#endif // !BOOST_HANA_EXAMPLE_CPPCON_2014_MATRIX_DET_HPP