sl@0: //-----------------------------------------------------------------------------
sl@0: // boost detail/reference_content.hpp header file
sl@0: // See http://www.boost.org for updates, documentation, and revision history.
sl@0: //-----------------------------------------------------------------------------
sl@0: //
sl@0: // Copyright (c) 2003
sl@0: // Eric Friedman
sl@0: //
sl@0: // Distributed under the Boost Software License, Version 1.0. (See
sl@0: // accompanying file LICENSE_1_0.txt or copy at
sl@0: // http://www.boost.org/LICENSE_1_0.txt)
sl@0: 
sl@0: #ifndef BOOST_DETAIL_REFERENCE_CONTENT_HPP
sl@0: #define BOOST_DETAIL_REFERENCE_CONTENT_HPP
sl@0: 
sl@0: #include "boost/config.hpp"
sl@0: 
sl@0: #if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
sl@0: #   include "boost/mpl/bool.hpp"
sl@0: #   include "boost/type_traits/has_nothrow_copy.hpp"
sl@0: #else
sl@0: #   include "boost/mpl/if.hpp"
sl@0: #   include "boost/type_traits/is_reference.hpp"
sl@0: #endif
sl@0: 
sl@0: #include "boost/mpl/void.hpp"
sl@0: 
sl@0: namespace boost {
sl@0: 
sl@0: namespace detail {
sl@0: 
sl@0: ///////////////////////////////////////////////////////////////////////////////
sl@0: // (detail) class template reference_content
sl@0: //
sl@0: // Non-Assignable wrapper for references.
sl@0: //
sl@0: template <typename RefT>
sl@0: class reference_content
sl@0: {
sl@0: private: // representation
sl@0: 
sl@0:     RefT content_;
sl@0: 
sl@0: public: // structors
sl@0: 
sl@0:     ~reference_content()
sl@0:     {
sl@0:     }
sl@0: 
sl@0:     reference_content(RefT r)
sl@0:         : content_( r )
sl@0:     {
sl@0:     }
sl@0: 
sl@0:     reference_content(const reference_content& operand)
sl@0:         : content_( operand.content_ )
sl@0:     {
sl@0:     }
sl@0: 
sl@0: private: // non-Assignable
sl@0: 
sl@0:     reference_content& operator=(const reference_content&);
sl@0: 
sl@0: public: // queries
sl@0: 
sl@0:     RefT get() const
sl@0:     {
sl@0:         return content_;
sl@0:     }
sl@0: 
sl@0: };
sl@0: 
sl@0: ///////////////////////////////////////////////////////////////////////////////
sl@0: // (detail) metafunction make_reference_content
sl@0: //
sl@0: // Wraps with reference_content if specified type is reference.
sl@0: //
sl@0: 
sl@0: template <typename T = mpl::void_> struct make_reference_content;
sl@0: 
sl@0: #if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
sl@0: 
sl@0: template <typename T>
sl@0: struct make_reference_content
sl@0: {
sl@0:     typedef T type;
sl@0: };
sl@0: 
sl@0: template <typename T>
sl@0: struct make_reference_content< T& >
sl@0: {
sl@0:     typedef reference_content<T&> type;
sl@0: };
sl@0: 
sl@0: #else // defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
sl@0: 
sl@0: template <typename T>
sl@0: struct make_reference_content
sl@0:     : mpl::if_<
sl@0:           is_reference<T>
sl@0:         , reference_content<T>
sl@0:         , T
sl@0:         >
sl@0: {
sl@0: };
sl@0: 
sl@0: #endif // BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION workaround
sl@0: 
sl@0: template <>
sl@0: struct make_reference_content< mpl::void_ >
sl@0: {
sl@0:     template <typename T>
sl@0:     struct apply
sl@0:         : make_reference_content<T>
sl@0:     {
sl@0:     };
sl@0: 
sl@0:     typedef mpl::void_ type;
sl@0: };
sl@0: 
sl@0: } // namespace detail
sl@0: 
sl@0: ///////////////////////////////////////////////////////////////////////////////
sl@0: // reference_content<T&> type traits specializations
sl@0: //
sl@0: 
sl@0: #if !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
sl@0: 
sl@0: template <typename T>
sl@0: struct has_nothrow_copy<
sl@0:       ::boost::detail::reference_content< T& >
sl@0:     >
sl@0:     : mpl::true_
sl@0: {
sl@0: };
sl@0: 
sl@0: #endif // !defined(BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)
sl@0: 
sl@0: } // namespace boost
sl@0: 
sl@0: #endif // BOOST_DETAIL_REFERENCE_CONTENT_HPP