1 | |
2 | // (C) Copyright Edward Diener 2011-2015 |
3 | // Use, modification and distribution are subject to the Boost Software License, |
4 | // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at |
5 | // http://www.boost.org/LICENSE_1_0.txt). |
6 | |
7 | #if !defined(BOOST_VMD_IS_EMPTY_LIST_HPP) |
8 | #define BOOST_VMD_IS_EMPTY_LIST_HPP |
9 | |
10 | #include <boost/vmd/detail/setup.hpp> |
11 | |
12 | #if BOOST_PP_VARIADICS |
13 | |
14 | #include <boost/vmd/detail/is_list.hpp> |
15 | |
16 | /* |
17 | |
18 | The succeeding comments in this file are in doxygen format. |
19 | |
20 | */ |
21 | |
22 | /** \file |
23 | */ |
24 | |
25 | /** \def BOOST_VMD_IS_EMPTY_LIST(sequence) |
26 | |
27 | \brief Tests whether a sequence is an empty Boost PP list. |
28 | |
29 | An empty Boost PP list consists of the single identifier 'BOOST_PP_NIL'. |
30 | This identifier also serves as a list terminator for a non-empty list. |
31 | |
32 | sequence = a preprocessor parameter |
33 | |
34 | returns = 1 if the sequence is an empty Boost PP list |
35 | 0 if it is not. |
36 | |
37 | The macro will generate a preprocessing error if the input |
38 | as an empty list marker, instead of being an identifier, is |
39 | a preprocessor token which VMD cannot parse, as in the |
40 | example '&BOOST_PP_NIL'. |
41 | |
42 | */ |
43 | |
44 | #define BOOST_VMD_IS_EMPTY_LIST(sequence) \ |
45 | BOOST_VMD_DETAIL_IS_LIST_IS_EMPTY_LIST_PROCESS(sequence) \ |
46 | /**/ |
47 | |
48 | /** \def BOOST_VMD_IS_EMPTY_LIST_D(d,sequence) |
49 | |
50 | \brief Tests whether a sequence is an empty Boost PP list. Re-entrant version. |
51 | |
52 | An empty Boost PP list consists of the single identifier 'BOOST_PP_NIL'. |
53 | This identifier also serves as a list terminator for a non-empty list. |
54 | |
55 | d = The next available BOOST_PP_WHILE iteration |
56 | sequence = a preprocessor parameter |
57 | |
58 | returns = 1 if the sequence is an empty Boost PP list |
59 | 0 if it is not. |
60 | |
61 | The macro will generate a preprocessing error if the input |
62 | as an empty list marker, instead of being an identifier, is |
63 | a preprocessor token which VMD cannot parse, as in the |
64 | example '&BOOST_PP_NIL'. |
65 | |
66 | */ |
67 | |
68 | #define BOOST_VMD_IS_EMPTY_LIST_D(d,sequence) \ |
69 | BOOST_VMD_DETAIL_IS_LIST_IS_EMPTY_LIST_PROCESS_D(d,sequence) \ |
70 | /**/ |
71 | |
72 | #endif /* BOOST_PP_VARIADICS */ |
73 | #endif /* BOOST_VMD_IS_EMPTY_LIST_HPP */ |
74 | |