boost/preprocessor/tuple/pop_back.hpp

   1 # /* **************************************************************************
   2 #  *                                                                          *
   3 #  *     (C) Copyright Edward Diener 2013.
   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_TUPLE_POP_BACK_HPP
  13 # define BOOST_PREPROCESSOR_TUPLE_POP_BACK_HPP
  14 #
  15 # include <boost/preprocessor/config/config.hpp>
  16 #
  17 # if BOOST_PP_VARIADICS
  18 #
  19 # include <boost/preprocessor/array/pop_back.hpp>
  20 # include <boost/preprocessor/array/to_tuple.hpp>
  21 # include <boost/preprocessor/comparison/greater.hpp>
  22 # include <boost/preprocessor/control/iif.hpp>
  23 # include <boost/preprocessor/tuple/size.hpp>
  24 # include <boost/preprocessor/tuple/to_array.hpp>
  25 #
  26 # /* BOOST_PP_TUPLE_POP_BACK */
  27 #
  28 # define BOOST_PP_TUPLE_POP_BACK(tuple) \
  29     BOOST_PP_IIF \
  30         ( \
  31         BOOST_PP_GREATER(BOOST_PP_TUPLE_SIZE(tuple),1), \
  32         BOOST_PP_TUPLE_POP_BACK_EXEC, \
  33         BOOST_PP_TUPLE_POP_BACK_RETURN \
  34         ) \
  35     (tuple) \
  36 /**/
  37 #
  38 # define BOOST_PP_TUPLE_POP_BACK_EXEC(tuple) \
  39     BOOST_PP_ARRAY_TO_TUPLE(BOOST_PP_ARRAY_POP_BACK(BOOST_PP_TUPLE_TO_ARRAY(tuple))) \
  40 /**/
  41 #
  42 # define BOOST_PP_TUPLE_POP_BACK_RETURN(tuple) tuple
  43 #
  44 # /* BOOST_PP_TUPLE_POP_BACK_Z */
  45 #
  46 # define BOOST_PP_TUPLE_POP_BACK_Z(z, tuple) \
  47     BOOST_PP_IIF \
  48         ( \
  49         BOOST_PP_GREATER(BOOST_PP_TUPLE_SIZE(tuple),1), \
  50         BOOST_PP_TUPLE_POP_BACK_Z_EXEC, \
  51         BOOST_PP_TUPLE_POP_BACK_Z_RETURN \
  52         ) \
  53     (z, tuple) \
  54 /**/
  55 #
  56 # define BOOST_PP_TUPLE_POP_BACK_Z_EXEC(z, tuple) \
  57     BOOST_PP_ARRAY_TO_TUPLE(BOOST_PP_ARRAY_POP_BACK_Z(z, BOOST_PP_TUPLE_TO_ARRAY(tuple))) \
  58 /**/
  59 #
  60 # define BOOST_PP_TUPLE_POP_BACK_Z_RETURN(z, tuple) tuple
  61 #
  62 # endif // BOOST_PP_VARIADICS
  63 #
  64 # endif // BOOST_PREPROCESSOR_TUPLE_POP_BACK_HPP