1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
|
/*=============================================================================
Copyright (c) 2001-2011 Joel de Guzman
Copyright (c) 2001-2011 Hartmut Kaiser
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)
==============================================================================*/
#if !defined(BOOST_SPIRIT_UNUSED_APRIL_16_2006_0616PM)
#define BOOST_SPIRIT_UNUSED_APRIL_16_2006_0616PM
#if defined(_MSC_VER)
#pragma once
#endif
#include <boost/config.hpp>
#include <boost/mpl/bool.hpp>
#if defined(BOOST_MSVC)
# pragma warning(push)
# pragma warning(disable: 4522) // multiple assignment operators specified warning
#endif
///////////////////////////////////////////////////////////////////////////////
namespace boost { namespace spirit
{
///////////////////////////////////////////////////////////////////////////
// We do not import fusion ::unused_type anymore to avoid boost::fusion
// being turned into an associate namespace for boost::spirit, as this
// interferes with ADL in unexpected ways. We rather copy the full
// unused_type implementation from boost::fusion.
///////////////////////////////////////////////////////////////////////////
struct unused_type
{
unused_type()
{
}
template <typename T>
unused_type(T const&)
{
}
template <typename T>
unused_type const&
operator=(T const&) const
{
return *this;
}
template <typename T>
unused_type&
operator=(T const&)
{
return *this;
}
unused_type const&
operator=(unused_type const&) const
{
return *this;
}
unused_type&
operator=(unused_type const&)
{
return *this;
}
};
unused_type const unused = unused_type();
namespace detail
{
struct unused_only
{
unused_only(unused_type const&) {}
};
}
template <typename Out>
inline Out& operator<<(Out& out, detail::unused_only const&)
{
return out;
}
template <typename In>
inline In& operator>>(In& in, unused_type&)
{
return in;
}
///////////////////////////////////////////////////////////////////////////
namespace traits
{
// We use this test to detect if the argument is not an unused_type
template <typename T> struct not_is_unused : mpl::true_ {};
template <> struct not_is_unused<unused_type> : mpl::false_ {};
}
}}
#if defined(BOOST_MSVC)
# pragma warning(pop)
#endif
#endif
|
