preprocessor/tuple/pop_back.hpp

0001 # /* **************************************************************************
0002 #  *                                                                          *
0003 #  *     (C) Copyright Edward Diener 2013.
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 # /* See http://www.boost.org for most recent version. */
0011 #
0012 # ifndef BOOST_PREPROCESSOR_TUPLE_POP_BACK_HPP
0013 # define BOOST_PREPROCESSOR_TUPLE_POP_BACK_HPP
0014 #
0015 # include <boost/preprocessor/config/config.hpp>
0016 # include <boost/preprocessor/array/pop_back.hpp>
0017 # include <boost/preprocessor/array/to_tuple.hpp>
0018 # include <boost/preprocessor/comparison/greater.hpp>
0019 # include <boost/preprocessor/control/iif.hpp>
0020 # include <boost/preprocessor/tuple/size.hpp>
0021 # include <boost/preprocessor/tuple/to_array.hpp>
0022 #
0023 # /* BOOST_PP_TUPLE_POP_BACK */
0024 #
0025 # define BOOST_PP_TUPLE_POP_BACK(tuple) \
0026     BOOST_PP_IIF \
0027         ( \
0028         BOOST_PP_GREATER(BOOST_PP_TUPLE_SIZE(tuple),1), \
0029         BOOST_PP_TUPLE_POP_BACK_EXEC, \
0030         BOOST_PP_TUPLE_POP_BACK_RETURN \
0031         ) \
0032     (tuple) \
0033 /**/
0034 #
0035 # define BOOST_PP_TUPLE_POP_BACK_EXEC(tuple) \
0036     BOOST_PP_ARRAY_TO_TUPLE(BOOST_PP_ARRAY_POP_BACK(BOOST_PP_TUPLE_TO_ARRAY(tuple))) \
0037 /**/
0038 #
0039 # define BOOST_PP_TUPLE_POP_BACK_RETURN(tuple) tuple
0040 #
0041 # /* BOOST_PP_TUPLE_POP_BACK_Z */
0042 #
0043 # define BOOST_PP_TUPLE_POP_BACK_Z(z, tuple) \
0044     BOOST_PP_IIF \
0045         ( \
0046         BOOST_PP_GREATER(BOOST_PP_TUPLE_SIZE(tuple),1), \
0047         BOOST_PP_TUPLE_POP_BACK_Z_EXEC, \
0048         BOOST_PP_TUPLE_POP_BACK_Z_RETURN \
0049         ) \
0050     (z, tuple) \
0051 /**/
0052 #
0053 # define BOOST_PP_TUPLE_POP_BACK_Z_EXEC(z, tuple) \
0054     BOOST_PP_ARRAY_TO_TUPLE(BOOST_PP_ARRAY_POP_BACK_Z(z, BOOST_PP_TUPLE_TO_ARRAY(tuple))) \
0055 /**/
0056 #
0057 # define BOOST_PP_TUPLE_POP_BACK_Z_RETURN(z, tuple) tuple
0058 #
0059 # endif // BOOST_PREPROCESSOR_TUPLE_POP_BACK_HPP