Merge from default version 2.14.0.
# /* 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_CAT_HPP
# define BOOST_PREPROCESSOR_CAT_HPP
#
# include <boost/preprocessor/config/config.hpp>
#
# /* BOOST_PP_CAT */
#
# if ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_MWCC()
# define BOOST_PP_CAT(a, b) BOOST_PP_CAT_I(a, b)
# else
# define BOOST_PP_CAT(a, b) BOOST_PP_CAT_OO((a, b))
# define BOOST_PP_CAT_OO(par) BOOST_PP_CAT_I ## par
# endif
#
# if ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_MSVC()
# define BOOST_PP_CAT_I(a, b) a ## b
# else
# define BOOST_PP_CAT_I(a, b) BOOST_PP_CAT_II(a ## b)
# define BOOST_PP_CAT_II(res) res
# endif
#
# endif