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
|
/*=============================================================================
Copyright (c) 2002-2003 Joel de Guzman
http://spirit.sourceforge.net/
Use, modification and distribution is subject to 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)
=============================================================================*/
// *** See the section "Look Ma' No Rules" in
// *** chapter "Techniques" of the Spirit documentation
// *** for information regarding this snippet
#include <iostream>
#include <boost/spirit/include/classic_core.hpp>
#include <boost/assert.hpp>
using namespace BOOST_SPIRIT_CLASSIC_NS;
namespace boost { namespace spirit
{
template <typename DerivedT>
struct sub_grammar : parser<DerivedT>
{
typedef sub_grammar self_t;
typedef DerivedT const& embed_t;
template <typename ScannerT>
struct result
{
typedef typename parser_result<
typename DerivedT::start_t, ScannerT>::type
type;
};
DerivedT const& derived() const
{ return *static_cast<DerivedT const*>(this); }
template <typename ScannerT>
typename parser_result<self_t, ScannerT>::type
parse(ScannerT const& scan) const
{
return derived().start.parse(scan);
}
};
}}
///////////////////////////////////////////////////////////////////////////////
//
// Client code
//
///////////////////////////////////////////////////////////////////////////////
struct skip_grammar : boost::spirit::sub_grammar<skip_grammar>
{
typedef
alternative<alternative<space_parser, sequence<sequence<
strlit<const char*>, kleene_star<difference<anychar_parser,
chlit<char> > > >, chlit<char> > >, sequence<sequence<
strlit<const char*>, kleene_star<difference<anychar_parser,
strlit<const char*> > > >, strlit<const char*> > >
start_t;
skip_grammar()
: start
(
space_p
| "//" >> *(anychar_p - '\n') >> '\n'
| "/*" >> *(anychar_p - "*/") >> "*/"
)
{}
start_t start;
};
int
main()
{
skip_grammar g;
bool success = parse(
"/*this is a comment*/\n//this is a c++ comment\n\n",
*g).full;
BOOST_ASSERT(success);
std::cout << "SUCCESS!!!\n";
return 0;
}
|
