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diff --git a/boost/variant/detail/element_index.hpp b/boost/variant/detail/element_index.hpp
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+//-----------------------------------------------------------------------------
+// boost variant/detail/element_index.hpp header file
+// See http://www.boost.org for updates, documentation, and revision history.
+//-----------------------------------------------------------------------------
+//
+// Copyright (c) 2014-2015 Antony Polukhin
+//
+// 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_VARIANT_DETAIL_ELEMENT_INDEX_HPP
+#define BOOST_VARIANT_DETAIL_ELEMENT_INDEX_HPP
+
+#include "boost/config.hpp"
+#include "boost/variant/recursive_wrapper_fwd.hpp"
+#include "boost/variant/variant_fwd.hpp"
+
+#include "boost/mpl/find_if.hpp"
+
+namespace boost { namespace detail { namespace variant {
+
+template <class VariantElement, class T>
+struct variant_element_functor :
+    boost::mpl::or_<
+        boost::is_same<VariantElement, T>,
+        boost::is_same<VariantElement, boost::recursive_wrapper<T> >,
+        boost::is_same<VariantElement, T& >
+    >
+{};
+
+template <class Types, class T>
+struct element_iterator_impl :
+    boost::mpl::find_if<
+        Types,
+        boost::mpl::or_<
+            variant_element_functor<boost::mpl::_1, T>,
+            variant_element_functor<boost::mpl::_1, typename boost::remove_cv<T>::type >
+        >
+    >
+{};
+
+template <class Variant, class T>
+struct element_iterator :
+    element_iterator_impl< typename Variant::types, T>
+{};
+
+template <class Variant, class T>
+struct holds_element :
+    boost::mpl::not_<
+        boost::is_same<
+            typename boost::mpl::end<typename Variant::types>::type,
+            typename element_iterator<Variant, T>::type
+        >
+    >
+{};
+
+
+}}} // namespace boost::detail::variant
+
+#endif // BOOST_VARIANT_DETAIL_ELEMENT_INDEX_HPP