1 // Copyright (c) 2001-2010 Hartmut Kaiser
2 //
3 // Distributed under the Boost Software License, Version 1.0. (See accompanying
4 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
5
6 // The main purpose of this example is to show how a single fusion sequence
7 // can be used to generate output of the elements in different sequences
8
9 #include <boost/config/warning_disable.hpp>
10 #include <boost/spirit/include/karma.hpp>
11 #include <boost/fusion/include/struct.hpp>
12 #include <boost/fusion/include/nview.hpp>
13 #include <boost/assign/std/vector.hpp>
14
15 namespace fusion = boost::fusion;
16 namespace karma = boost::spirit::karma;
17
18 ///////////////////////////////////////////////////////////////////////////////
19 namespace client
20 {
21 // Our employee struct
22 struct employee
23 {
24 std::string surname;
25 std::string forename;
26 int age;
27 double salary;
28 std::string department;
29 };
30
31 // define iterator type
32 typedef std::back_insert_iterator<std::string> iterator_type;
33
34 // This is the output routine taking a format description and the data to
35 // print
36 template <typename Generator, typename Sequence>
generate(Generator const & g,Sequence const & s)37 void generate(Generator const& g, Sequence const& s)
38 {
39 std::string generated;
40 iterator_type sink(generated);
41 karma::generate(sink, g, s);
42 std::cout << generated << std::endl;
43 }
44 }
45
46 // We need to tell fusion about our employee struct to make it a first-class
47 // fusion citizen. This has to be in global scope. Note that we don't need to
48 // list the members of our struct in the same sequence a they are defined
49 BOOST_FUSION_ADAPT_STRUCT(
50 client::employee,
51 (int, age)
52 (std::string, surname)
53 (std::string, forename)
54 (std::string, department)
55 (double, salary)
56 )
57
58 ///////////////////////////////////////////////////////////////////////////////
main()59 int main()
60 {
61 std::string str;
62
63 // some employees
64 client::employee john = { "John", "Smith", 25, 2000.50, "Sales" };
65 client::employee mary = { "Mary", "Higgins", 23, 2200.36, "Marketing" };
66 client::employee tom = { "Tom", "Taylor", 48, 3200.00, "Boss" };
67
68 // print data about employees in different formats
69 {
70 // print forename and age
71 client::generate(
72 karma::string << ", " << karma::int_,
73 fusion::as_nview<2, 0>(john));
74
75 // print surname, forename, and salary
76 client::generate(
77 karma::string << ' ' << karma::string << ": " << karma::double_,
78 fusion::as_nview<1, 2, 4>(mary));
79
80 // print forename, age, and department
81 client::generate(
82 karma::string << ": " << karma::int_ << " (" << karma::string << ')',
83 fusion::as_nview<2, 0, 3>(tom));
84 }
85
86 // now make a list of all employees and print them all
87 std::vector<client::employee> employees;
88 {
89 using namespace boost::assign;
90 employees += john, mary, tom;
91 }
92
93 // print surname, forename, and salary for all employees
94 {
95 typedef
96 fusion::result_of::as_nview<client::employee const, 1, 2, 4>::type
97 names_and_salary;
98
99 karma::rule<client::iterator_type, names_and_salary()> r =
100 karma::string << ' ' << karma::string << ": " << karma::double_;
101
102 client::generate(r % karma::eol, employees);
103 }
104 return 0;
105 }
106