is_empty_or_1.hpp 1.2 KB

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  1. # /* **************************************************************************
  2. # * *
  3. # * (C) Copyright Paul Mensonides 2003.
  4. # * Distributed under the Boost Software License, Version 1.0. (See
  5. # * accompanying file LICENSE_1_0.txt or copy at
  6. # * http://www.boost.org/LICENSE_1_0.txt)
  7. # * *
  8. # ************************************************************************** */
  9. #
  10. # /* See http://www.boost.org for most recent version. */
  11. #
  12. # ifndef BOOST_PREPROCESSOR_FACILITIES_IS_EMPTY_OR_1_HPP
  13. # define BOOST_PREPROCESSOR_FACILITIES_IS_EMPTY_OR_1_HPP
  14. #
  15. # include <boost/preprocessor/control/iif.hpp>
  16. # include <boost/preprocessor/facilities/empty.hpp>
  17. # include <boost/preprocessor/facilities/identity.hpp>
  18. # include <boost/preprocessor/facilities/is_1.hpp>
  19. # include <boost/preprocessor/facilities/is_empty.hpp>
  20. #
  21. # /* BOOST_PP_IS_EMPTY_OR_1 */
  22. #
  23. # define BOOST_PP_IS_EMPTY_OR_1(x) \
  24. BOOST_PP_IIF( \
  25. BOOST_PP_IS_EMPTY(x BOOST_PP_EMPTY()), \
  26. BOOST_PP_IDENTITY(1), \
  27. BOOST_PP_IS_1 \
  28. )(x) \
  29. /**/
  30. #
  31. # endif