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diff --git a/src/boost/libs/hana/example/misc/dimensional_analysis.cpp b/src/boost/libs/hana/example/misc/dimensional_analysis.cpp
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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)
+
+#include <boost/hana/equal.hpp>
+#include <boost/hana/minus.hpp>
+#include <boost/hana/plus.hpp>
+#include <boost/hana/tuple.hpp>
+#include <boost/hana/zip_with.hpp>
+
+#include <functional>
+namespace hana = boost::hana;
+
+
+//
+// Example of implementing basic dimensional analysis using Hana
+//
+
+
+// base dimensions                              M  L  T  I  K  J  N
+using mass        = decltype(hana::tuple_c<int, 1, 0, 0, 0, 0, 0, 0>);
+using length      = decltype(hana::tuple_c<int, 0, 1, 0, 0, 0, 0, 0>);
+using time_       = decltype(hana::tuple_c<int, 0, 0, 1, 0, 0, 0, 0>);
+using charge      = decltype(hana::tuple_c<int, 0, 0, 0, 1, 0, 0, 0>);
+using temperature = decltype(hana::tuple_c<int, 0, 0, 0, 0, 1, 0, 0>);
+using intensity   = decltype(hana::tuple_c<int, 0, 0, 0, 0, 0, 1, 0>);
+using amount      = decltype(hana::tuple_c<int, 0, 0, 0, 0, 0, 0, 1>);
+
+// composite dimensions
+using velocity     = decltype(hana::tuple_c<int, 0, 1, -1, 0, 0, 0, 0>); // M/T
+using acceleration = decltype(hana::tuple_c<int, 0, 1, -2, 0, 0, 0, 0>); // M/T^2
+using force        = decltype(hana::tuple_c<int, 1, 1, -2, 0, 0, 0, 0>); // ML/T^2
+
+
+template <typename Dimensions>
+struct quantity {
+    double value_;
+
+    explicit quantity(double v) : value_(v) { }
+
+    template <typename OtherDimensions>
+    explicit quantity(quantity<OtherDimensions> other)
+      : value_(other.value_)
+    {
+      static_assert(Dimensions{} == OtherDimensions{},
+        "Constructing quantities with incompatible dimensions!");
+    }
+
+    explicit operator double() const { return value_; }
+};
+
+template <typename D1, typename D2>
+auto operator*(quantity<D1> a, quantity<D2> b) {
+    using D = decltype(hana::zip_with(std::plus<>{}, D1{}, D2{}));
+    return quantity<D>{static_cast<double>(a) * static_cast<double>(b)};
+}
+
+template <typename D1, typename D2>
+auto operator/(quantity<D1> a, quantity<D2> b) {
+    using D = decltype(hana::zip_with(std::minus<>{}, D1{}, D2{}));
+    return quantity<D>{static_cast<double>(a) / static_cast<double>(b)};
+}
+
+int main() {
+    quantity<mass>         m{10.3};
+    quantity<length>       d{3.6};
+    quantity<time_>        t{2.4};
+    quantity<velocity>     v{d / t};
+    quantity<acceleration> a{3.9};
+    quantity<force>        f{m * a};
+}