preprocessor/facilities/is_empty_or_1.hpp

0001 # /* **************************************************************************
0002 #  *                                                                          *
0003 #  *     (C) Copyright Paul Mensonides 2003.
0004 #  *     Distributed under the Boost Software License, Version 1.0. (See
0005 #  *     accompanying file LICENSE_1_0.txt or copy at
0006 #  *     http://www.boost.org/LICENSE_1_0.txt)
0007 #  *                                                                          *
0008 #  ************************************************************************** */
0009 0010 ">#
0011 # /* See http://www.boost.org for most recent version. */
0012 0013 ">#
0014 # ifndef BOOST_PREPROCESSOR_FACILITIES_IS_EMPTY_OR_1_HPP
0015 # define BOOST_PREPROCESSOR_FACILITIES_IS_EMPTY_OR_1_HPP
0016 0017 ">#
0018 # include <boost/preprocessor/control/iif.hpp>
0019 # include <boost/preprocessor/facilities/empty.hpp>
0020 # include <boost/preprocessor/facilities/identity.hpp>
0021 # include <boost/preprocessor/facilities/is_1.hpp>
0022 # include <boost/preprocessor/facilities/is_empty.hpp>
0023 0024 ">#
0025 # /* BOOST_PP_IS_EMPTY_OR_1 */
0026 0027 ">#
0028 # define BOOST_PP_IS_EMPTY_OR_1(x) \
0029     BOOST_PP_IIF( \
0030         BOOST_PP_IS_EMPTY(x BOOST_PP_EMPTY()), \
0031         BOOST_PP_IDENTITY(1), \
0032         BOOST_PP_IS_1 \
0033     )(x) \
0034     /**/
0035 0036 ">#
0037 # endif