1# /* **************************************************************************
2# * *
3# * (C) Copyright Paul Mensonides 2002.
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_SEQ_CAT_HPP
13# define BOOST_PREPROCESSOR_SEQ_CAT_HPP
14#
15# include <boost/preprocessor/arithmetic/dec.hpp>
16# include <boost/preprocessor/config/config.hpp>
17# include <boost/preprocessor/control/if.hpp>
18# include <boost/preprocessor/seq/fold_left.hpp>
19# include <boost/preprocessor/seq/seq.hpp>
20# include <boost/preprocessor/seq/size.hpp>
21# include <boost/preprocessor/tuple/eat.hpp>
22#
23# /* BOOST_PP_SEQ_CAT */
24#
25# define BOOST_PP_SEQ_CAT(seq) \
26 BOOST_PP_IF( \
27 BOOST_PP_DEC(BOOST_PP_SEQ_SIZE(seq)), \
28 BOOST_PP_SEQ_CAT_I, \
29 BOOST_PP_SEQ_HEAD \
30 )(seq) \
31 /**/
32# define BOOST_PP_SEQ_CAT_I(seq) BOOST_PP_SEQ_FOLD_LEFT(BOOST_PP_SEQ_CAT_O, BOOST_PP_SEQ_HEAD(seq), BOOST_PP_SEQ_TAIL(seq))
33#
34# define BOOST_PP_SEQ_CAT_O(s, st, elem) BOOST_PP_SEQ_CAT_O_I(st, elem)
35# define BOOST_PP_SEQ_CAT_O_I(a, b) a ## b
36#
37# /* BOOST_PP_SEQ_CAT_S */
38#
39# define BOOST_PP_SEQ_CAT_S(s, seq) \
40 BOOST_PP_IF( \
41 BOOST_PP_DEC(BOOST_PP_SEQ_SIZE(seq)), \
42 BOOST_PP_SEQ_CAT_S_I_A, \
43 BOOST_PP_SEQ_CAT_S_I_B \
44 )(s, seq) \
45 /**/
46# define BOOST_PP_SEQ_CAT_S_I_A(s, seq) BOOST_PP_SEQ_FOLD_LEFT_ ## s(BOOST_PP_SEQ_CAT_O, BOOST_PP_SEQ_HEAD(seq), BOOST_PP_SEQ_TAIL(seq))
47# define BOOST_PP_SEQ_CAT_S_I_B(s, seq) BOOST_PP_SEQ_HEAD(seq)
48#
49# endif
50

source code of boost/boost/preprocessor/seq/cat.hpp