filter.hpp 1.1 KB

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  1. /*=============================================================================
  2. Copyright (c) 2001-2011 Joel de Guzman
  3. Copyright (c) 2005-2006 Dan Marsden
  4. Distributed under the Boost Software License, Version 1.0. (See accompanying
  5. file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  6. ==============================================================================*/
  7. #if !defined(FUSION_FILTER_02122005_1839)
  8. #define FUSION_FILTER_02122005_1839
  9. #include <boost/fusion/support/config.hpp>
  10. #include <boost/fusion/view/filter_view/filter_view.hpp>
  11. #include <boost/type_traits/is_same.hpp>
  12. namespace boost { namespace fusion
  13. {
  14. namespace result_of
  15. {
  16. template <typename Sequence, typename T>
  17. struct filter
  18. {
  19. typedef filter_view<Sequence, is_same<mpl::_, T> > type;
  20. };
  21. }
  22. template <typename T, typename Sequence>
  23. BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
  24. inline typename result_of::filter<Sequence const, T>::type
  25. filter(Sequence const& seq)
  26. {
  27. return filter_view<const Sequence, is_same<mpl::_, T> >(seq);
  28. }
  29. }}
  30. #endif