| # /* 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 (2002-2011) */ |
| # /* Revised by Edward Diener (2011,2014,2020) */ |
| # |
| # /* See http://www.boost.org for most recent version. */ |
| # |
| # ifndef BOOST_PREPROCESSOR_TUPLE_ELEM_HPP |
| # define BOOST_PREPROCESSOR_TUPLE_ELEM_HPP |
| # |
| # include <boost/preprocessor/cat.hpp> |
| # include <boost/preprocessor/config/config.hpp> |
| # include <boost/preprocessor/facilities/expand.hpp> |
| # include <boost/preprocessor/facilities/overload.hpp> |
| # include <boost/preprocessor/tuple/rem.hpp> |
| # include <boost/preprocessor/variadic/elem.hpp> |
| # include <boost/preprocessor/tuple/detail/is_single_return.hpp> |
| # |
| # if BOOST_PP_VARIADICS_MSVC |
| # define BOOST_PP_TUPLE_ELEM(...) BOOST_PP_TUPLE_ELEM_I(BOOST_PP_OVERLOAD(BOOST_PP_TUPLE_ELEM_O_, __VA_ARGS__), (__VA_ARGS__)) |
| # define BOOST_PP_TUPLE_ELEM_I(m, args) BOOST_PP_TUPLE_ELEM_II(m, args) |
| # define BOOST_PP_TUPLE_ELEM_II(m, args) BOOST_PP_CAT(m ## args,) |
| /* |
| Use BOOST_PP_REM_CAT if it is a single element tuple ( which might be empty ) |
| else use BOOST_PP_REM. This fixes a VC++ problem with an empty tuple and BOOST_PP_TUPLE_ELEM |
| functionality. See tuple_elem_bug_test.cxx. |
| */ |
| # define BOOST_PP_TUPLE_ELEM_O_2(n, tuple) \ |
| BOOST_PP_VARIADIC_ELEM(n, BOOST_PP_EXPAND(BOOST_PP_TUPLE_IS_SINGLE_RETURN(BOOST_PP_REM_CAT,BOOST_PP_REM,tuple) tuple)) \ |
| /**/ |
| # else |
| # define BOOST_PP_TUPLE_ELEM(...) BOOST_PP_OVERLOAD(BOOST_PP_TUPLE_ELEM_O_, __VA_ARGS__)(__VA_ARGS__) |
| # define BOOST_PP_TUPLE_ELEM_O_2(n, tuple) BOOST_PP_VARIADIC_ELEM(n, BOOST_PP_REM tuple) |
| # endif |
| # define BOOST_PP_TUPLE_ELEM_O_3(size, n, tuple) BOOST_PP_TUPLE_ELEM_O_2(n, tuple) |
| # |
| # /* directly used elsewhere in Boost... */ |
| # |
| # define BOOST_PP_TUPLE_ELEM_1_0(a) a |
| # |
| # define BOOST_PP_TUPLE_ELEM_2_0(a, b) a |
| # define BOOST_PP_TUPLE_ELEM_2_1(a, b) b |
| # |
| # define BOOST_PP_TUPLE_ELEM_3_0(a, b, c) a |
| # define BOOST_PP_TUPLE_ELEM_3_1(a, b, c) b |
| # define BOOST_PP_TUPLE_ELEM_3_2(a, b, c) c |
| # |
| # endif |