ceph/src/boost/libs/spirit/example/karma/reorder_struct.cpp

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