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diff --git a/boost/hana/ext/std/pair.hpp b/boost/hana/ext/std/pair.hpp
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+/*!
+@file
+Adapts `std::pair` for use with Hana.
+
+@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_EXT_STD_PAIR_HPP
+#define BOOST_HANA_EXT_STD_PAIR_HPP
+
+#include <boost/hana/config.hpp>
+#include <boost/hana/fwd/core/make.hpp>
+#include <boost/hana/fwd/core/tag_of.hpp>
+#include <boost/hana/fwd/first.hpp>
+#include <boost/hana/fwd/second.hpp>
+
+#include <utility>
+
+
+#ifdef BOOST_HANA_DOXYGEN_INVOKED
+namespace std {
+    //! @ingroup group-ext-std
+    //! Adaptation of `std::pair` for Hana.
+    //!
+    //!
+    //! Modeled concepts
+    //! ----------------
+    //! A `std::pair` models exactly the same concepts as a `hana::pair`.
+    //! Please refer to the documentation of `hana::pair` for details.
+    //!
+    //! @include example/ext/std/pair.cpp
+    template <typename First, typename Second>
+    struct pair { };
+}
+#endif
+
+
+BOOST_HANA_NAMESPACE_BEGIN
+    namespace ext { namespace std { struct pair_tag; }}
+
+    template <typename First, typename Second>
+    struct tag_of<std::pair<First, Second>> {
+        using type = ext::std::pair_tag;
+    };
+
+    //////////////////////////////////////////////////////////////////////////
+    // Product
+    //////////////////////////////////////////////////////////////////////////
+    template <>
+    struct make_impl<ext::std::pair_tag> {
+        template <typename X, typename Y>
+        static constexpr decltype(auto) apply(X&& x, Y&& y) {
+            return std::make_pair(static_cast<X&&>(x),
+                                  static_cast<Y&&>(y));
+        }
+    };
+
+    template <>
+    struct first_impl<ext::std::pair_tag> {
+        template <typename T, typename U>
+        static constexpr T const& apply(std::pair<T, U> const& p)
+        {  return p.first; }
+
+        template <typename T, typename U>
+        static constexpr T& apply(std::pair<T, U>& p)
+        {  return p.first; }
+
+        template <typename T, typename U>
+        static constexpr T&& apply(std::pair<T, U>&& p)
+        {  return static_cast<T&&>(p.first); }
+    };
+
+    template <>
+    struct second_impl<ext::std::pair_tag> {
+        template <typename T, typename U>
+        static constexpr U const& apply(std::pair<T, U> const& p)
+        {  return p.second; }
+
+        template <typename T, typename U>
+        static constexpr U& apply(std::pair<T, U>& p)
+        {  return p.second; }
+
+        template <typename T, typename U>
+        static constexpr U&& apply(std::pair<T, U>&& p)
+        {  return static_cast<U&&>(p.second); }
+    };
+BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_EXT_STD_PAIR_HPP