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
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
|
/*=============================================================================
Copyright (c) 2002-2010 Hartmut Kaiser
Copyright (c) 2002-2010 Joel de Guzman
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)
=============================================================================*/
///////////////////////////////////////////////////////////////////////////////
//
// This sample demonstrates a generator for a comma separated list of numbers.
// No actions. It is based on the example qi/num_lists.cpp for reading in
// some numbers to generate.
//
///////////////////////////////////////////////////////////////////////////////
#include <boost/spirit/include/qi.hpp>
#include <boost/spirit/include/karma.hpp>
#include <iostream>
#include <string>
#include <vector>
namespace client
{
///////////////////////////////////////////////////////////////////////////
// Our number list parser, please see the example qi/numlist1.cpp for
// more information
///////////////////////////////////////////////////////////////////////////
template <typename Iterator>
bool parse_numbers(Iterator first, Iterator last, std::vector<double>& v)
{
using boost::spirit::qi::double_;
using boost::spirit::qi::phrase_parse;
using boost::spirit::ascii::space;
bool r = phrase_parse(first, last, double_ % ',', space, v);
if (first != last)
return false;
return r;
}
//[tutorial_karma_numlist3_complex
// a simple complex number representation z = a + bi
struct complex
{
complex (double a, double b = 0.0) : a(a), b(b) {}
double a;
double b;
};
// the streaming operator for the type complex
std::ostream&
operator<< (std::ostream& os, complex const& z)
{
os << "{" << z.a << "," << z.b << "}";
return os;
}
//]
///////////////////////////////////////////////////////////////////////////
// Our number list generator
///////////////////////////////////////////////////////////////////////////
//[tutorial_karma_numlist3
template <typename OutputIterator, typename Container>
bool generate_numbers(OutputIterator& sink, Container const& v)
{
using boost::spirit::karma::stream;
using boost::spirit::karma::generate;
using boost::spirit::karma::eol;
bool r = generate(
sink, // destination: output iterator
stream % eol, // the generator
v // the data to output
);
return r;
}
//]
}
////////////////////////////////////////////////////////////////////////////
// Main program
////////////////////////////////////////////////////////////////////////////
int
main()
{
std::cout << "/////////////////////////////////////////////////////////\n\n";
std::cout << "\tA comma separated list generator for Spirit...\n\n";
std::cout << "/////////////////////////////////////////////////////////\n\n";
std::cout << "Give me a comma separated list of numbers.\n";
std::cout << "Type [q or Q] to quit\n\n";
std::string str;
while (getline(std::cin, str))
{
if (str.empty() || str[0] == 'q' || str[0] == 'Q')
break;
std::vector<double> v; // here we put the data gotten from input
if (client::parse_numbers(str.begin(), str.end(), v))
{
// ok, we got some numbers, fill a vector of client::complex
// instances and print them back out
std::vector<client::complex> vc;
std::vector<double>::const_iterator end = v.end();
for (std::vector<double>::const_iterator it = v.begin();
it != end; ++it)
{
double real(*it);
if (++it != end)
vc.push_back(client::complex(real, *it));
else {
vc.push_back(client::complex(real));
break;
}
}
std::cout << "-------------------------\n";
std::string generated;
std::back_insert_iterator<std::string> sink(generated);
if (!client::generate_numbers(sink, vc))
{
std::cout << "-------------------------\n";
std::cout << "Generating failed\n";
std::cout << "-------------------------\n";
}
else
{
std::cout << "-------------------------\n";
std::cout << "Generated:\n" << generated << "\n";
std::cout << "-------------------------\n";
}
}
else
{
std::cout << "-------------------------\n";
std::cout << "Parsing failed\n";
std::cout << "-------------------------\n";
}
}
std::cout << "Bye... :-) \n\n";
return 0;
}
|
