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+
+// Copyright Oliver Kowalke 2014.
+// 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_CONTEXT_DETAIL_INDEX_SEQUENCE_H
+#define BOOST_CONTEXT_DETAIL_INDEX_SEQUENCE_H
+
+#include <cstddef>
+
+#include <boost/config.hpp>
+
+#include <boost/context/detail/config.hpp>
+
+#ifdef BOOST_HAS_ABI_HEADERS
+# include BOOST_ABI_PREFIX
+#endif
+
+namespace boost {
+namespace context {
+namespace detail {
+
+#if ! defined(BOOST_CONTEXT_NO_CXX14_INTEGER_SEQUENCE)
+template< std::size_t ... I >
+using index_sequence = std::index_sequence< I ... >;
+template< std::size_t I >
+using make_index_sequence = std::make_index_sequence< I >;
+template< typename ... T >
+using index_sequence_for = std::index_sequence_for< T ... >;
+#else
+//http://stackoverflow.com/questions/17424477/implementation-c14-make-integer-sequence
+
+template< std::size_t ... I >
+struct index_sequence {
+ using type = index_sequence;
+ using value_type = std::size_t;
+ static constexpr std::size_t size() {
+ return sizeof ... (I);
+ }
+};
+
+template< typename Seq1, typename Seq2 >
+struct concat_sequence;
+
+template< std::size_t ... I1, std::size_t ... I2 >
+struct concat_sequence< index_sequence< I1 ... >, index_sequence< I2 ... > > : public index_sequence< I1 ..., (sizeof ... (I1)+I2) ... > {
+};
+
+template< std::size_t I >
+struct make_index_sequence : public concat_sequence< typename make_index_sequence< I/2 >::type,
+ typename make_index_sequence< I-I/2 >::type > {
+};
+
+template<>
+struct make_index_sequence< 0 > : public index_sequence<> {
+};
+template<>
+struct make_index_sequence< 1 > : public index_sequence< 0 > {
+};
+
+template< typename ... T >
+using index_sequence_for = make_index_sequence< sizeof ... (T) >;
+#endif
+
+}}}
+
+#ifdef BOOST_HAS_ABI_HEADERS
+#include BOOST_ABI_SUFFIX
+#endif
+
+#endif // BOOST_CONTEXT_DETAIL_INDEX_SEQUENCE_H