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diff --git a/src/boost/libs/hana/test/_include/support/identity.hpp b/src/boost/libs/hana/test/_include/support/identity.hpp
new file mode 100644
index 000000000..c6799cbe8
--- /dev/null
+++ b/src/boost/libs/hana/test/_include/support/identity.hpp
@@ -0,0 +1,159 @@
+// 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 TEST_SUPPORT_IDENTITY_HPP
+#define TEST_SUPPORT_IDENTITY_HPP
+
+#include <boost/hana/chain.hpp>
+#include <boost/hana/eval_if.hpp>
+#include <boost/hana/functional/compose.hpp>
+#include <boost/hana/functional/partial.hpp>
+#include <boost/hana/fwd/adjust_if.hpp>
+#include <boost/hana/fwd/ap.hpp>
+#include <boost/hana/fwd/equal.hpp>
+#include <boost/hana/fwd/flatten.hpp>
+#include <boost/hana/fwd/less.hpp>
+#include <boost/hana/fwd/lift.hpp>
+#include <boost/hana/lazy.hpp>
+#include <boost/hana/transform.hpp>
+
+#include <type_traits>
+
+
+struct Identity;
+
+template <typename T>
+struct identity_t {
+    T value;
+    using hana_tag = Identity;
+};
+
+struct make_identity {
+    template <typename T>
+    constexpr identity_t<typename std::decay<T>::type> operator()(T&& t) const {
+        return {static_cast<T&&>(t)};
+    }
+};
+
+constexpr make_identity identity{};
+
+
+namespace boost { namespace hana {
+    //////////////////////////////////////////////////////////////////////////
+    // Comparable
+    //////////////////////////////////////////////////////////////////////////
+    template <>
+    struct equal_impl<Identity, Identity> {
+        template <typename Id1, typename Id2>
+        static constexpr auto apply(Id1 x, Id2 y)
+        { return hana::equal(x.value, y.value); }
+    };
+
+    //////////////////////////////////////////////////////////////////////////
+    // Orderable
+    //////////////////////////////////////////////////////////////////////////
+    template <>
+    struct less_impl<Identity, Identity> {
+        template <typename Id1, typename Id2>
+        static constexpr auto apply(Id1 x, Id2 y)
+        { return hana::less(x.value, y.value); }
+    };
+
+    //////////////////////////////////////////////////////////////////////////
+    // Functor
+    //
+    // Define either one to select which MCD is used:
+    //  BOOST_HANA_TEST_FUNCTOR_TRANSFORM_MCD
+    //  BOOST_HANA_TEST_FUNCTOR_ADJUST_MCD_MCD
+    //
+    // If neither is defined, the MCD used is unspecified.
+    //////////////////////////////////////////////////////////////////////////
+#ifdef BOOST_HANA_TEST_FUNCTOR_TRANSFORM_MCD
+    template <>
+    struct transform_impl<Identity> {
+        template <typename Id, typename F>
+        static constexpr auto apply(Id self, F f)
+        { return ::identity(f(self.value)); }
+    };
+#else
+    template <>
+    struct adjust_if_impl<Identity> {
+        struct get_value {
+            template <typename T>
+            constexpr auto operator()(T t) const { return t.value; }
+        };
+
+        template <typename Id, typename P, typename F>
+        static constexpr auto apply(Id self, P p, F f) {
+            auto x = hana::eval_if(p(self.value),
+                hana::make_lazy(hana::compose(f, get_value{}))(self),
+                hana::make_lazy(get_value{})(self)
+            );
+            return ::identity(x);
+        }
+    };
+#endif
+
+    //////////////////////////////////////////////////////////////////////////
+    // Applicative
+    //
+    // Define either one to select which MCD is used:
+    //  BOOST_HANA_TEST_APPLICATIVE_FULL_MCD
+    //  BOOST_HANA_TEST_APPLICATIVE_MONAD_MCD
+    //
+    // If neither is defined, the MCD used is unspecified.
+    //////////////////////////////////////////////////////////////////////////
+    template <>
+    struct lift_impl<Identity> {
+        template <typename X>
+        static constexpr auto apply(X x)
+        { return ::identity(x); }
+    };
+#ifdef BOOST_HANA_TEST_APPLICATIVE_FULL_MCD
+    template <>
+    struct ap_impl<Identity> {
+        template <typename F, typename X>
+        static constexpr auto apply(F f, X x)
+        { return ::identity(f.value(x.value)); }
+    };
+#else
+    template <>
+    struct ap_impl<Identity> {
+        template <typename F, typename X>
+        static constexpr decltype(auto) apply(F&& f, X&& x) {
+            return hana::chain(
+                static_cast<F&&>(f),
+                hana::partial(hana::transform, static_cast<X&&>(x))
+            );
+        }
+    };
+#endif
+
+    //////////////////////////////////////////////////////////////////////////
+    // Monad
+    //
+    // Define either one to select which MCD is used:
+    //  BOOST_HANA_TEST_MONAD_FLATTEN_MCD
+    //  BOOST_HANA_TEST_MONAD_CHAIN_MCD
+    //
+    // If neither is defined, the MCD used is unspecified.
+    //////////////////////////////////////////////////////////////////////////
+#ifdef BOOST_HANA_TEST_MONAD_FLATTEN_MCD
+    template <>
+    struct flatten_impl<Identity> {
+        template <typename Id>
+        static constexpr auto apply(Id self)
+        { return self.value; }
+    };
+#else
+    template <>
+    struct chain_impl<Identity> {
+        template <typename X, typename F>
+        static constexpr auto apply(X x, F f)
+        { return f(x.value); }
+    };
+#endif
+}} // end namespace boost::hana
+
+#endif // !TEST_SUPPORT_IDENTITY_HPP