text: # /* **************************************************************************
  #  *                                                                          *
  #  *     (C) Copyright Paul Mensonides 2002.
  #  *     Distributed under the Boost Software License, Version 1.0. (See
  #  *     accompanying file LICENSE_1_0.txt or copy at
  #  *     http://www.boost.org/LICENSE_1_0.txt)
  #  *                                                                          *
  #  ************************************************************************** */
  #
  # /* See http://www.boost.org for most recent version. */
  #
  # ifndef BOOST_PREPROCESSOR_SEQ_FOR_EACH_HPP
  # define BOOST_PREPROCESSOR_SEQ_FOR_EACH_HPP
  #
  # include <boost/preprocessor/arithmetic/dec.hpp>
  # include <boost/preprocessor/config/config.hpp>
  # include <boost/preprocessor/control/if.hpp>
  # include <boost/preprocessor/control/iif.hpp>
  # include <boost/preprocessor/repetition/for.hpp>
  # include <boost/preprocessor/seq/seq.hpp>
  # include <boost/preprocessor/seq/size.hpp>
  # include <boost/preprocessor/seq/detail/is_empty.hpp>
  # include <boost/preprocessor/tuple/elem.hpp>
  # include <boost/preprocessor/tuple/rem.hpp>
  #
  # /* BOOST_PP_SEQ_FOR_EACH */
  #
  # if ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_EDG()
  #    define BOOST_PP_SEQ_FOR_EACH(macro, data, seq) BOOST_PP_SEQ_FOR_EACH_DETAIL_CHECK(macro, data, seq)
  # else
  #    define BOOST_PP_SEQ_FOR_EACH(macro, data, seq) BOOST_PP_SEQ_FOR_EACH_D(macro, data, seq)
  #    define BOOST_PP_SEQ_FOR_EACH_D(macro, data, seq) BOOST_PP_SEQ_FOR_EACH_DETAIL_CHECK(macro, data, seq)
  # endif
  #
  #    define BOOST_PP_SEQ_FOR_EACH_DETAIL_CHECK_EXEC(macro, data, seq) BOOST_PP_FOR((macro, data, seq, BOOST_PP_SEQ_SIZE(seq)), BOOST_PP_SEQ_FOR_EACH_P, BOOST_PP_SEQ_FOR_EACH_O, BOOST_PP_SEQ_FOR_EACH_M)
  #    define BOOST_PP_SEQ_FOR_EACH_DETAIL_CHECK_EMPTY(macro, data, seq)
  #
  #    define BOOST_PP_SEQ_FOR_EACH_DETAIL_CHECK(macro, data, seq) \
          BOOST_PP_IIF \
              ( \
              BOOST_PP_SEQ_DETAIL_IS_NOT_EMPTY(seq), \
              BOOST_PP_SEQ_FOR_EACH_DETAIL_CHECK_EXEC, \
              BOOST_PP_SEQ_FOR_EACH_DETAIL_CHECK_EMPTY \
              ) \
          (macro, data, seq) \
  /**/
  #
  # define BOOST_PP_SEQ_FOR_EACH_P(r, x) BOOST_PP_TUPLE_ELEM(4, 3, x)
  #
  # if BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_STRICT()
  #    define BOOST_PP_SEQ_FOR_EACH_O(r, x) BOOST_PP_SEQ_FOR_EACH_O_I x
  # else
  #    define BOOST_PP_SEQ_FOR_EACH_O(r, x) BOOST_PP_SEQ_FOR_EACH_O_I(BOOST_PP_TUPLE_ELEM(4, 0, x), BOOST_PP_TUPLE_ELEM(4, 1, x), BOOST_PP_TUPLE_ELEM(4, 2, x), BOOST_PP_TUPLE_ELEM(4, 3, x))
  # endif
  #
  # define BOOST_PP_SEQ_FOR_EACH_O_I(macro, data, seq, sz) \
      BOOST_PP_SEQ_FOR_EACH_O_I_DEC(macro, data, seq, BOOST_PP_DEC(sz)) \
  /**/
  # define BOOST_PP_SEQ_FOR_EACH_O_I_DEC(macro, data, seq, sz) \
      ( \
      macro, \
      data, \
      BOOST_PP_IF \
          ( \
          sz, \
          BOOST_PP_SEQ_FOR_EACH_O_I_TAIL, \
          BOOST_PP_SEQ_FOR_EACH_O_I_NIL \
          ) \
      (seq), \
      sz \
      ) \
  /**/
  # define BOOST_PP_SEQ_FOR_EACH_O_I_TAIL(seq) BOOST_PP_SEQ_TAIL(seq)
  # define BOOST_PP_SEQ_FOR_EACH_O_I_NIL(seq) BOOST_PP_NIL
  #
  # if BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_STRICT()
  #    define BOOST_PP_SEQ_FOR_EACH_M(r, x) BOOST_PP_SEQ_FOR_EACH_M_IM(r, BOOST_PP_TUPLE_REM_4 x)
  #    define BOOST_PP_SEQ_FOR_EACH_M_IM(r, im) BOOST_PP_SEQ_FOR_EACH_M_I(r, im)
  # else
  #    define BOOST_PP_SEQ_FOR_EACH_M(r, x) BOOST_PP_SEQ_FOR_EACH_M_I(r, BOOST_PP_TUPLE_ELEM(4, 0, x), BOOST_PP_TUPLE_ELEM(4, 1, x), BOOST_PP_TUPLE_ELEM(4, 2, x), BOOST_PP_TUPLE_ELEM(4, 3, x))
  # endif
  #
  # define BOOST_PP_SEQ_FOR_EACH_M_I(r, macro, data, seq, sz) macro(r, data, BOOST_PP_SEQ_HEAD(seq))
  #
  # /* BOOST_PP_SEQ_FOR_EACH_R */
  #
  # if ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_EDG()
  #    define BOOST_PP_SEQ_FOR_EACH_R(r, macro, data, seq) BOOST_PP_SEQ_FOR_EACH_DETAIL_CHECK_R(r, macro, data, seq)
  # else
  #    define BOOST_PP_SEQ_FOR_EACH_R(r, macro, data, seq) BOOST_PP_SEQ_FOR_EACH_R_I(r, macro, data, seq)
  #    define BOOST_PP_SEQ_FOR_EACH_R_I(r, macro, data, seq) BOOST_PP_SEQ_FOR_EACH_DETAIL_CHECK_R(r, macro, data, seq)
  # endif
  #
  #    define BOOST_PP_SEQ_FOR_EACH_DETAIL_CHECK_EXEC_R(r, macro, data, seq) BOOST_PP_FOR_ ## r((macro, data, seq, BOOST_PP_SEQ_SIZE(seq)), BOOST_PP_SEQ_FOR_EACH_P, BOOST_PP_SEQ_FOR_EACH_O, BOOST_PP_SEQ_FOR_EACH_M)
  #    define BOOST_PP_SEQ_FOR_EACH_DETAIL_CHECK_EMPTY_R(r, macro, data, seq)
  #
  #    define BOOST_PP_SEQ_FOR_EACH_DETAIL_CHECK_R(r, macro, data, seq) \
          BOOST_PP_IIF \
              ( \
              BOOST_PP_SEQ_DETAIL_IS_NOT_EMPTY(seq), \
              BOOST_PP_SEQ_FOR_EACH_DETAIL_CHECK_EXEC_R, \
              BOOST_PP_SEQ_FOR_EACH_DETAIL_CHECK_EMPTY_R \
              ) \
          (r, macro, data, seq) \
  /**/
  #
  # endif
  