# /* Copyright (C) 2001

 #  * Housemarque Oy

 #  * http://www.housemarque.com

 #  *

 #  * 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)

 #  */

 #

 # /* Revised by Paul Mensonides (2002) */

 #

 # /* See http://www.boost.org for most recent version. */

 #

 # ifndef BOOST_PREPROCESSOR_ARITHMETIC_SUB_HPP

 # define BOOST_PREPROCESSOR_ARITHMETIC_SUB_HPP

 #

 # include <boost/preprocessor/arithmetic/dec.hpp>

 # include <boost/preprocessor/config/config.hpp>

 # include <boost/preprocessor/control/while.hpp>

 # include <boost/preprocessor/tuple/elem.hpp>

 #

 # /* BOOST_PP_SUB */

 #

 # if ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_EDG()

 #    define BOOST_PP_SUB(x, y) BOOST_PP_TUPLE_ELEM(2, 0, BOOST_PP_WHILE(BOOST_PP_SUB_P, BOOST_PP_SUB_O, (x, y)))

 # else

 #    define BOOST_PP_SUB(x, y) BOOST_PP_SUB_I(x, y)

 #    define BOOST_PP_SUB_I(x, y) BOOST_PP_TUPLE_ELEM(2, 0, BOOST_PP_WHILE(BOOST_PP_SUB_P, BOOST_PP_SUB_O, (x, y)))

 # endif

 #

 # define BOOST_PP_SUB_P(d, xy) BOOST_PP_TUPLE_ELEM(2, 1, xy)

 #

 # if ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_MWCC()

 #    define BOOST_PP_SUB_O(d, xy) BOOST_PP_SUB_O_I xy

 # else

 #    define BOOST_PP_SUB_O(d, xy) BOOST_PP_SUB_O_I(BOOST_PP_TUPLE_ELEM(2, 0, xy), BOOST_PP_TUPLE_ELEM(2, 1, xy))

 # endif

 #

 # define BOOST_PP_SUB_O_I(x, y) (BOOST_PP_DEC(x), BOOST_PP_DEC(y))

 #

 # /* BOOST_PP_SUB_D */

 #

 # if ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_EDG()

 #    define BOOST_PP_SUB_D(d, x, y) BOOST_PP_TUPLE_ELEM(2, 0, BOOST_PP_WHILE_ ## d(BOOST_PP_SUB_P, BOOST_PP_SUB_O, (x, y)))

 # else

 #    define BOOST_PP_SUB_D(d, x, y) BOOST_PP_SUB_D_I(d, x, y)

 #    define BOOST_PP_SUB_D_I(d, x, y) BOOST_PP_TUPLE_ELEM(2, 0, BOOST_PP_WHILE_ ## d(BOOST_PP_SUB_P, BOOST_PP_SUB_O, (x, y)))

 # endif

 #

 # endif