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_FIRST_N_HPP
13# define BOOST_PREPROCESSOR_SEQ_FIRST_N_HPP
14#
15# include <boost/preprocessor/config/config.hpp>
16# include <boost/preprocessor/control/if.hpp>
17# include <boost/preprocessor/seq/detail/split.hpp>
18# include <boost/preprocessor/tuple/eat.hpp>
19# include <boost/preprocessor/tuple/elem.hpp>
20#
21# /* BOOST_PP_SEQ_FIRST_N */
22#
23# if ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_EDG()
24# define BOOST_PP_SEQ_FIRST_N(n, seq) BOOST_PP_IF(n, BOOST_PP_TUPLE_ELEM, BOOST_PP_TUPLE_EAT_3)(2, 0, BOOST_PP_SEQ_SPLIT(n, seq (nil)))
25# else
26# define BOOST_PP_SEQ_FIRST_N(n, seq) BOOST_PP_SEQ_FIRST_N_I(n, seq)
27# define BOOST_PP_SEQ_FIRST_N_I(n, seq) BOOST_PP_IF(n, BOOST_PP_TUPLE_ELEM, BOOST_PP_TUPLE_EAT_3)(2, 0, BOOST_PP_SEQ_SPLIT(n, seq (nil)))
28# endif
29#
30# endif
31

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