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+/* Copyright 2016-2017 Joaquin M Lopez Munoz.
+ * 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)
+ *
+ * See http://www.boost.org/libs/poly_collection for library home page.
+ */
+
+#ifndef BOOST_POLY_COLLECTION_DETAIL_IS_FINAL_HPP
+#define BOOST_POLY_COLLECTION_DETAIL_IS_FINAL_HPP
+
+#if defined(_MSC_VER)
+#pragma once
+#endif
+
+#include <boost/type_traits/is_final.hpp>
+#include <type_traits>
+
+/* technique explained at
+ * http://bannalia.blogspot.com/2016/09/compile-time-checking-existence-of.html
+ */
+
+namespace boost{
+namespace poly_collection{
+namespace detail{
+namespace is_final_fallback{
+
+template<typename T> using is_final=boost::is_final<T>;
+
+struct hook{};
+
+}}}}
+
+namespace std{
+
+template<>
+struct is_void< ::boost::poly_collection::detail::is_final_fallback::hook>:
+ std::false_type
+{
+ template<typename T>
+ static constexpr bool is_final_f()
+ {
+ using namespace ::boost::poly_collection::detail::is_final_fallback;
+ return is_final<T>::value;
+ }
+};
+
+} /* namespace std */
+
+namespace boost{
+
+namespace poly_collection{
+
+namespace detail{
+
+template<typename T>
+struct is_final:std::integral_constant<
+ bool,
+ std::is_void<is_final_fallback::hook>::template is_final_f<T>()
+>{};
+
+} /* namespace poly_collection::detail */
+
+} /* namespace poly_collection */
+
+} /* namespace boost */
+
+#endif