multi_index/detail/unbounded.hpp

0001 /* Copyright 2003-2013 Joaquin M Lopez Munoz.
0002  * Distributed under the Boost Software License, Version 1.0.
0003  * (See accompanying file LICENSE_1_0.txt or copy at
0004  * http://www.boost.org/LICENSE_1_0.txt)
0005  *
0006  * See http://www.boost.org/libs/multi_index for library home page.
0007  */
0008
0009 #ifndef BOOST_MULTI_INDEX_DETAIL_UNBOUNDED_HPP
0010 #define BOOST_MULTI_INDEX_DETAIL_UNBOUNDED_HPP
0011
0012 #if defined(_MSC_VER)
0013 #pragma once
0014 #endif
0015
0016 #include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
0017 #include <boost/detail/workaround.hpp>
0018
0019 namespace boost{
0020
0021 namespace multi_index{
0022
0023 /* dummy type and variable for use in ordered_index::range() */
0024
0025 /* ODR-abiding technique shown at the example attached to
0026  * http://lists.boost.org/Archives/boost/2006/07/108355.php
0027  */
0028
0029 namespace detail{class unbounded_helper;}
0030
0031 detail::unbounded_helper unbounded(detail::unbounded_helper);
0032
0033 namespace detail{
0034
0035 class unbounded_helper
0036 {
0037   unbounded_helper(){}
0038   unbounded_helper(const unbounded_helper&){}
0039   friend unbounded_helper multi_index::unbounded(unbounded_helper);
0040 };
0041
0042 typedef unbounded_helper (*unbounded_type)(unbounded_helper);
0043
0044 } /* namespace multi_index::detail */
0045
0046 inline detail::unbounded_helper unbounded(detail::unbounded_helper)
0047 {
0048   return detail::unbounded_helper();
0049 }
0050
0051 /* tags used in the implementation of range */
0052
0053 namespace detail{
0054
0055 struct none_unbounded_tag{};
0056 struct lower_unbounded_tag{};
0057 struct upper_unbounded_tag{};
0058 struct both_unbounded_tag{};
0059
0060 } /* namespace multi_index::detail */
0061
0062 } /* namespace multi_index */
0063
0064 } /* namespace boost */
0065
0066 #endif