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+// underlying_type.hpp ---------------------------------------------------------//
+
+// Copyright Beman Dawes, 2009
+// Copyright (C) 2011-2012 Vicente J. Botet Escriba
+// Copyright (C) 2012 Anthony Williams
+// Copyright (C) 2014 Andrey Semashev
+
+// Distributed under the Boost Software License, Version 1.0.
+// See http://www.boost.org/LICENSE_1_0.txt
+
+#ifndef BOOST_CORE_UNDERLYING_TYPE_HPP
+#define BOOST_CORE_UNDERLYING_TYPE_HPP
+
+#include <boost/config.hpp>
+
+// GCC 4.7 and later seem to provide std::underlying_type
+#if !defined(BOOST_NO_CXX11_HDR_TYPE_TRAITS) || (defined(BOOST_GCC) && BOOST_GCC >= 40700 && defined(__GXX_EXPERIMENTAL_CXX0X__))
+#include <type_traits>
+#define BOOST_DETAIL_HAS_STD_UNDERLYING_TYPE
+#endif
+
+#ifdef BOOST_HAS_PRAGMA_ONCE
+#pragma once
+#endif
+
+namespace boost {
+
+namespace detail {
+
+template< typename EnumType, typename Void = void >
+struct underlying_type_impl;
+
+#if defined(BOOST_NO_CXX11_SCOPED_ENUMS)
+
+// Support for boost/core/scoped_enum.hpp
+template< typename EnumType >
+struct underlying_type_impl< EnumType, typename EnumType::is_boost_scoped_enum_tag >
+{
+ /**
+ * The member typedef type names the underlying type of EnumType. It is EnumType::underlying_type when the EnumType is an emulated scoped enum,
+ */
+ typedef typename EnumType::underlying_type type;
+};
+
+#endif
+
+#if defined(BOOST_DETAIL_HAS_STD_UNDERLYING_TYPE)
+
+template< typename EnumType, typename Void >
+struct underlying_type_impl
+{
+ typedef typename std::underlying_type< EnumType >::type type;
+};
+
+#endif
+
+} // namespace detail
+
+#if !defined(BOOST_NO_CXX11_SCOPED_ENUMS) && !defined(BOOST_DETAIL_HAS_STD_UNDERLYING_TYPE)
+#define BOOST_NO_UNDERLYING_TYPE
+#endif
+
+/**
+ * Meta-function to get the underlying type of a scoped enum.
+ *
+ * Requires EnumType must be an enum type or the emulation of a scoped enum.
+ * If BOOST_NO_UNDERLYING_TYPE is defined, the implementation will not be able
+ * to deduce the underlying type of enums. The user is expected to specialize
+ * this trait in this case.
+ */
+template< typename EnumType >
+struct underlying_type :
+ public detail::underlying_type_impl< EnumType >
+{
+};
+
+} // namespace boost
+
+#endif // BOOST_CORE_UNDERLYING_TYPE_HPP