1/*=============================================================================
2 Copyright (c) 2001-2011 Hartmut Kaiser
3 http://spirit.sourceforge.net/
4
5 Distributed under the Boost Software License, Version 1.0. (See accompanying
6 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
7=============================================================================*/
8//[porting_guide_classic_includes
9#include <boost/spirit/include/classic.hpp>
10#include <boost/spirit/include/phoenix1.hpp>
11#include <iostream>
12#include <string>
13//]
14
15//[porting_guide_classic_namespace
16using namespace boost::spirit::classic;
17//]
18
19//[porting_guide_classic_grammar
20struct roman : public grammar<roman>
21{
22 template <typename ScannerT>
23 struct definition
24 {
25 definition(roman const& self)
26 {
27 hundreds.add
28 ("C" , 100)("CC" , 200)("CCC" , 300)("CD" , 400)("D" , 500)
29 ("DC" , 600)("DCC" , 700)("DCCC" , 800)("CM" , 900) ;
30
31 tens.add
32 ("X" , 10)("XX" , 20)("XXX" , 30)("XL" , 40)("L" , 50)
33 ("LX" , 60)("LXX" , 70)("LXXX" , 80)("XC" , 90) ;
34
35 ones.add
36 ("I" , 1)("II" , 2)("III" , 3)("IV" , 4)("V" , 5)
37 ("VI" , 6)("VII" , 7)("VIII" , 8)("IX" , 9) ;
38
39 first = eps_p [phoenix::var(v&: self.r) = phoenix::val(v: 0)]
40 >> ( +ch_p(ch: 'M') [phoenix::var(v&: self.r) += phoenix::val(v: 1000)]
41 || hundreds [phoenix::var(v&: self.r) += phoenix::_1]
42 || tens [phoenix::var(v&: self.r) += phoenix::_1]
43 || ones [phoenix::var(v&: self.r) += phoenix::_1]
44 ) ;
45 }
46
47 rule<ScannerT> first;
48 symbols<unsigned> hundreds;
49 symbols<unsigned> tens;
50 symbols<unsigned> ones;
51
52 rule<ScannerT> const& start() const { return first; }
53 };
54
55 roman(unsigned& r_) : r(r_) {}
56 unsigned& r;
57};
58//]
59
60int main()
61{
62 {
63 //[porting_guide_classic_parse
64 std::string input("1,1");
65 parse_info<std::string::iterator> pi = parse(first_: input.begin(), last: input.end(), p: int_p);
66
67 if (pi.hit)
68 std::cout << "successful match!\n";
69
70 if (pi.full)
71 std::cout << "full match!\n";
72 else
73 std::cout << "stopped at: " << std::string(pi.stop, input.end()) << "\n";
74
75 std::cout << "matched length: " << pi.length << "\n";
76 //]
77 }
78
79 {
80 //[porting_guide_classic_phrase_parse
81 std::string input(" 1, 1");
82 parse_info<std::string::iterator> pi = parse(first: input.begin(), last: input.end(), p: int_p, skip: space_p);
83
84 if (pi.hit)
85 std::cout << "successful match!\n";
86
87 if (pi.full)
88 std::cout << "full match!\n";
89 else
90 std::cout << "stopped at: " << std::string(pi.stop, input.end()) << "\n";
91
92 std::cout << "matched length: " << pi.length << "\n";
93 //]
94 }
95
96 {
97 //[porting_guide_classic_use_grammar
98 std::string input("MMIX"); // MMIX == 2009
99 unsigned value = 0;
100 roman r(value);
101 parse_info<std::string::iterator> pi = parse(first_: input.begin(), last: input.end(), p: r);
102 if (pi.hit)
103 std::cout << "successfully matched: " << value << "\n";
104 //]
105 }
106 return 0;
107}
108
109

source code of boost/libs/spirit/example/qi/porting_guide_classic.cpp