1
2#ifndef BOOST_MPL_AUX_PREPROCESSOR_TOKEN_EQUAL_HPP_INCLUDED
3#define BOOST_MPL_AUX_PREPROCESSOR_TOKEN_EQUAL_HPP_INCLUDED
4
5// Copyright Paul Mensonides 2003
6// Copyright Aleksey Gurtovoy 2003-2004
7//
8// Distributed under the Boost Software License, Version 1.0.
9// (See accompanying file LICENSE_1_0.txt or copy at
10// http://www.boost.org/LICENSE_1_0.txt)
11//
12// See http://www.boost.org/libs/mpl for documentation.
13
14// $Id$
15// $Date$
16// $Revision$
17
18#include <boost/mpl/aux_/preprocessor/is_seq.hpp>
19
20#include <boost/preprocessor/if.hpp>
21#include <boost/preprocessor/logical/bitand.hpp>
22#include <boost/preprocessor/logical/compl.hpp>
23#include <boost/preprocessor/tuple/eat.hpp>
24#include <boost/preprocessor/cat.hpp>
25
26// compares tokens 'a' and 'b' for equality:
27//
28// #define BOOST_MPL_PP_TOKEN_EQUAL_apple(x) x
29// #define BOOST_MPL_PP_TOKEN_EQUAL_orange(x) x
30//
31// BOOST_PP_ASSERT( BOOST_PP_NOT( BOOST_MPL_PP_TOKEN_EQUAL(apple, abc) ) )
32// BOOST_PP_ASSERT( BOOST_PP_NOT( BOOST_MPL_PP_TOKEN_EQUAL(abc, apple) ) )
33// BOOST_PP_ASSERT( BOOST_PP_NOT( BOOST_MPL_PP_TOKEN_EQUAL(apple, orange) ) )
34// BOOST_PP_ASSERT( BOOST_MPL_PP_TOKEN_EQUAL(apple, apple) )
35// BOOST_PP_ASSERT( BOOST_MPL_PP_TOKEN_EQUAL(orange, orange) )
36
37#define BOOST_MPL_PP_TOKEN_EQUAL(a, b) \
38 BOOST_PP_IIF( \
39 BOOST_PP_BITAND( \
40 BOOST_MPL_PP_IS_SEQ( BOOST_PP_CAT(BOOST_MPL_PP_TOKEN_EQUAL_, a)((unused)) ) \
41 , BOOST_MPL_PP_IS_SEQ( BOOST_PP_CAT(BOOST_MPL_PP_TOKEN_EQUAL_, b)((unused)) ) \
42 ) \
43 , BOOST_MPL_PP_TOKEN_EQUAL_I \
44 , 0 BOOST_PP_TUPLE_EAT(2) \
45 )(a, b) \
46/**/
47
48#define BOOST_MPL_PP_TOKEN_EQUAL_I(a, b) \
49 BOOST_PP_COMPL(BOOST_MPL_PP_IS_SEQ( \
50 BOOST_MPL_PP_TOKEN_EQUAL_ ## a( \
51 BOOST_MPL_PP_TOKEN_EQUAL_ ## b \
52 )((unused)) \
53 )) \
54/**/
55
56#endif // BOOST_MPL_AUX_PREPROCESSOR_TOKEN_EQUAL_HPP_INCLUDED
57