text: // Boost.Bimap
  //
  // Copyright (c) 2006-2007 Matias Capeletto
  //
  // 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)
  
  /// \file relation/symmetrical_base.hpp
  /// \brief Base class for symmetrical types
  
  #ifndef BOOST_BIMAP_RELATION_SYMMETRICAL_BASE_HPP
  #define BOOST_BIMAP_RELATION_SYMMETRICAL_BASE_HPP
  
  #if defined(_MSC_VER) && (_MSC_VER>=1200)
  #pragma once
  #endif
  
  #include <boost/config.hpp>
  
  #include <boost/mpl/if.hpp>
  #include <boost/type_traits/remove_const.hpp>
  
  // Boost.Bimap
  #include <boost/bimap/tags/tagged.hpp>
  #include <boost/bimap/tags/support/default_tagged.hpp>
  
  #include <boost/bimap/relation/member_at.hpp>
  
  
  namespace boost {
  namespace bimaps {
  namespace relation {
  
  /// \brief Base of symetrical tagged types.
  /**
  
                                                             **/
  
  template< class TA, class TB, bool force_mutable = false >
  class symmetrical_base
  {
  
      public:
  
      typedef BOOST_DEDUCED_TYPENAME tags::support::default_tagged
      <
          TA,
          member_at::left
  
      >::type tagged_left_type;
  
      typedef BOOST_DEDUCED_TYPENAME tags::support::default_tagged
      <
          TB,
          member_at::right
  
      >::type tagged_right_type;
  
      public:
  
      //@{
          /// The type stored in the relation
  
          typedef BOOST_DEDUCED_TYPENAME ::boost::mpl::if_c< force_mutable,
  
              BOOST_DEDUCED_TYPENAME ::boost::remove_const<
                  BOOST_DEDUCED_TYPENAME tagged_left_type::value_type >::type,
              BOOST_DEDUCED_TYPENAME tagged_left_type::value_type
  
          >::type left_value_type;
  
          typedef BOOST_DEDUCED_TYPENAME ::boost::mpl::if_c< force_mutable,
  
              BOOST_DEDUCED_TYPENAME ::boost::remove_const<
                  BOOST_DEDUCED_TYPENAME tagged_right_type::value_type >::type,
              BOOST_DEDUCED_TYPENAME tagged_right_type::value_type
  
          >::type right_value_type;
      //@}
  
      //@{
          /// The tag of the member. By default it is \c member_at::{side}
          typedef BOOST_DEDUCED_TYPENAME tagged_left_type ::tag  left_tag;
          typedef BOOST_DEDUCED_TYPENAME tagged_right_type::tag right_tag;
      //@}
  };
  
  
  
  } // namespace relation
  } // namespace bimaps
  } // namespace boost
  
  
  #endif // BOOST_BIMAP_RELATION_SYMMETRICAL_BASE_HPP
  
  