equal_to_impl.hpp 1.3 KB

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  1. /*=============================================================================
  2. Copyright (c) 2011 Eric Niebler
  3. Distributed under the Boost Software License, Version 1.0. (See accompanying
  4. file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  5. ==============================================================================*/
  6. #if !defined(BOOST_FUSION_SINGLE_VIEW_ITERATOR_JUL_07_2011_1348PM)
  7. #define BOOST_FUSION_SINGLE_VIEW_ITERATOR_JUL_07_2011_1348PM
  8. #include <boost/fusion/support/config.hpp>
  9. #include <boost/mpl/assert.hpp>
  10. #include <boost/mpl/equal_to.hpp>
  11. #include <boost/type_traits/is_same.hpp>
  12. #include <boost/type_traits/add_const.hpp>
  13. namespace boost { namespace fusion
  14. {
  15. struct single_view_iterator_tag;
  16. namespace extension
  17. {
  18. template<typename Tag>
  19. struct equal_to_impl;
  20. template<>
  21. struct equal_to_impl<single_view_iterator_tag>
  22. {
  23. template<typename It1, typename It2>
  24. struct apply
  25. : mpl::equal_to<typename It1::position, typename It2::position>
  26. {
  27. BOOST_MPL_ASSERT((is_same<typename add_const<typename It1::single_view_type>::type,
  28. typename add_const<typename It2::single_view_type>::type>));
  29. };
  30. };
  31. }
  32. }}
  33. #endif