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diff --git a/boost/hof/detail/compressed_pair.hpp b/boost/hof/detail/compressed_pair.hpp
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+++ b/boost/hof/detail/compressed_pair.hpp
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+/*=============================================================================
+    Copyright (c) 2015 Paul Fultz II
+    compressed_pair.h
+    Distributed under the Boost Software License, Version 1.0. (See accompanying
+    file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+==============================================================================*/
+
+#ifndef BOOST_HOF_GUARD_COMPRESSED_PAIR_H
+#define BOOST_HOF_GUARD_COMPRESSED_PAIR_H
+
+#include <boost/hof/detail/delegate.hpp>
+#include <boost/hof/detail/move.hpp>
+#include <boost/hof/detail/forward.hpp>
+#include <boost/hof/config.hpp>
+#include <boost/hof/always.hpp>
+#include <boost/hof/alias.hpp>
+
+#ifndef BOOST_HOF_COMPRESSED_PAIR_USE_EBO_WORKAROUND
+#define BOOST_HOF_COMPRESSED_PAIR_USE_EBO_WORKAROUND !BOOST_HOF_HAS_EBO
+#endif
+
+namespace boost { namespace hof { namespace detail {
+
+template<class First, class Second, class=void>
+struct compressed_pair;
+
+template<int I, class T, class U>
+struct pair_tag
+{};
+
+#if BOOST_HOF_COMPRESSED_PAIR_USE_EBO_WORKAROUND
+
+template<class T, class U>
+struct is_same_template
+: std::false_type
+{};
+
+template<template<class...> class X, class... Ts, class... Us>
+struct is_same_template<X<Ts...>, X<Us...>>
+: std::true_type
+{};
+
+#if (defined(__GNUC__) && !defined (__clang__) && __GNUC__ == 4 && __GNUC_MINOR__ < 7)
+
+template<class T, class U>
+struct is_related_template
+: std::false_type
+{};
+
+#else
+
+template<class T, class U>
+struct is_related_template
+: is_same_template<T, U>
+{};
+
+#endif
+
+template<class T, class U>
+struct is_related
+: std::integral_constant<bool, std::is_base_of<T, U>::value || std::is_base_of<U, T>::value || is_related_template<T, U>::value>
+{};
+
+template<int I, class T, class U>
+struct pair_holder
+: std::conditional<(
+    is_related<T, U>::value), 
+    detail::alias_empty<T, pair_tag<I, T, U>>,
+    detail::alias_try_inherit<T, pair_tag<I, T, U>>
+>::type
+{};
+#else
+template<int I, class T, class U>
+struct pair_holder
+: detail::alias_try_inherit<T, pair_tag<I, T, U>>
+{};
+#endif
+
+// TODO: Empty optimizations for MSVC
+template<
+    class First, 
+    class Second
+>
+struct compressed_pair<First, Second>
+: pair_holder<0, First, Second>::type, pair_holder<1, Second, First>::type
+{
+    typedef typename pair_holder<0, First, Second>::type first_base;
+    typedef typename pair_holder<1, Second, First>::type second_base;
+    template<class X, class Y, 
+        BOOST_HOF_ENABLE_IF_CONSTRUCTIBLE(First, X&&), 
+        BOOST_HOF_ENABLE_IF_CONSTRUCTIBLE(Second, Y&&)
+    >
+    constexpr compressed_pair(X&& x, Y&& y) 
+    noexcept(BOOST_HOF_IS_NOTHROW_CONSTRUCTIBLE(first_base, X&&) && BOOST_HOF_IS_NOTHROW_CONSTRUCTIBLE(second_base, Y&&))
+    : first_base(BOOST_HOF_FORWARD(X)(x)), second_base(BOOST_HOF_FORWARD(Y)(y))
+    {}
+
+    BOOST_HOF_INHERIT_DEFAULT(compressed_pair, first_base, second_base)
+
+    template<class Base, class... Xs>
+    constexpr const Base& get_alias_base(Xs&&... xs) const noexcept
+    {
+        return boost::hof::always_ref(*this)(xs...);
+    }
+
+    template<class... Xs>
+    constexpr const First& first(Xs&&... xs) const noexcept
+    {
+        return boost::hof::alias_value(this->get_alias_base<first_base>(xs...), xs...);
+    }
+
+    template<class... Xs>
+    constexpr const Second& second(Xs&&... xs) const noexcept
+    {
+        return boost::hof::alias_value(this->get_alias_base<second_base>(xs...), xs...);
+    }
+
+};
+
+template<class T, class U>
+constexpr compressed_pair<T, U> make_compressed_pair(T x, U y)
+noexcept(BOOST_HOF_IS_NOTHROW_MOVE_CONSTRUCTIBLE(T) && BOOST_HOF_IS_NOTHROW_MOVE_CONSTRUCTIBLE(U))
+{
+    return {static_cast<T&&>(x), static_cast<U&&>(y)};
+}
+
+
+}}} // namespace boost::hof
+
+#endif