boost_preprocessor/include/boost/preprocessor/detail/check.hpp

# /* **************************************************************************
#  *                                                                          *
#  *     (C) Copyright Paul Mensonides 2002.  Permission to copy, use,        *
#  *     modify, sell, and distribute this software is granted provided       *
#  *     this copyright notice appears in all copies.  This software is       *
#  *     provided "as is" without express or implied warranty, and with       *
#  *     no claim at to its suitability for any purpose.                      *
#  *                                                                          *
#  ************************************************************************** */
#
# /* See http://www.boost.org for most recent version. */
#
# ifndef BOOST_PREPROCESSOR_DETAIL_CHECK_HPP
# define BOOST_PREPROCESSOR_DETAIL_CHECK_HPP
#
# include <boost/preprocessor/cat.hpp>
# include <boost/preprocessor/config/config.hpp>
#
# /* BOOST_PP_CHECK */
#
# if ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_MWCC()
#    define BOOST_PP_CHECK(x, type) BOOST_PP_CHECK_D(x, type)
# else
#    define BOOST_PP_CHECK(x, type) BOOST_PP_CHECK_OO((x, type))
#    define BOOST_PP_CHECK_OO(par) BOOST_PP_CHECK_D ## par
# endif
#
# if ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_MSVC()
#    define BOOST_PP_CHECK_D(x, type) BOOST_PP_CHECK_1(BOOST_PP_CAT(BOOST_PP_CHECK_RESULT_, type x))
#    define BOOST_PP_CHECK_1(chk) BOOST_PP_CHECK_2(chk)
#    define BOOST_PP_CHECK_2(res, _) res
# else
#    define BOOST_PP_CHECK_D(x, type) BOOST_PP_CHECK_1(type x)
#    define BOOST_PP_CHECK_1(chk) BOOST_PP_CHECK_2(chk)
#    define BOOST_PP_CHECK_2(chk) BOOST_PP_CHECK_3((BOOST_PP_CHECK_RESULT_ ## chk))
#    define BOOST_PP_CHECK_3(im) BOOST_PP_CHECK_5(BOOST_PP_CHECK_4 im)
#    define BOOST_PP_CHECK_4(res, _) res
#    define BOOST_PP_CHECK_5(res) res
# endif
#
# define BOOST_PP_CHECK_RESULT_1 1, BOOST_PP_NIL
#
# endif