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libs/spirit/example/qi/employee.cpp

/*=============================================================================
    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)
=============================================================================*/
///////////////////////////////////////////////////////////////////////////////
//
//  A parser for arbitrary tuples. This example presents a parser
//  for an employee structure.
//
//  [ JDG May 9, 2007 ]
//
///////////////////////////////////////////////////////////////////////////////

#include <boost/config/warning_disable.hpp>
#include <boost/spirit/include/qi.hpp>
#include <boost/spirit/include/phoenix_core.hpp>
#include <boost/spirit/include/phoenix_operator.hpp>
#include <boost/spirit/include/phoenix_object.hpp>
#include <boost/fusion/include/adapt_struct.hpp>
#include <boost/fusion/include/io.hpp>

#include <iostream>
#include <string>
#include <complex>

namespace client
{
    namespace qi = boost::spirit::qi;
    namespace ascii = boost::spirit::ascii;

    ///////////////////////////////////////////////////////////////////////////
    //  Our employee struct
    ///////////////////////////////////////////////////////////////////////////
    //[tutorial_employee_struct
    struct employee
    {
        int age;
        std::string surname;
        std::string forename;
        double salary;
    };
    //]
}

// We need to tell fusion about our employee struct
// to make it a first-class fusion citizen. This has to
// be in global scope.

//[tutorial_employee_adapt_struct
BOOST_FUSION_ADAPT_STRUCT(
    client::employee,
    (int, age)
    (std::string, surname)
    (std::string, forename)
    (double, salary)
)
//]

namespace client
{
    ///////////////////////////////////////////////////////////////////////////////
    //  Our employee parser
    ///////////////////////////////////////////////////////////////////////////////
    //[tutorial_employee_parser
    template <typename Iterator>
    struct employee_parser : qi::grammar<Iterator, employee(), ascii::space_type>
    {
        employee_parser() : employee_parser::base_type(start)
        {
            using qi::int_;
            using qi::lit;
            using qi::double_;
            using qi::lexeme;
            using ascii::char_;

            quoted_string %= lexeme['"' >> +(char_ - '"') >> '"'];

            start %=
                lit("employee")
                >> '{'
                >>  int_ >> ','
                >>  quoted_string >> ','
                >>  quoted_string >> ','
                >>  double_
                >>  '}'
                ;
        }

        qi::rule<Iterator, std::string(), ascii::space_type> quoted_string;
        qi::rule<Iterator, employee(), ascii::space_type> start;
    };
    //]
}

////////////////////////////////////////////////////////////////////////////
//  Main program
////////////////////////////////////////////////////////////////////////////
int
main()
{
    std::cout << "/////////////////////////////////////////////////////////\n\n";
    std::cout << "\t\tAn employee parser for Spirit...\n\n";
    std::cout << "/////////////////////////////////////////////////////////\n\n";

    std::cout
        << "Give me an employee of the form :"
        << "employee{age, \"surname\", \"forename\", salary } \n";
    std::cout << "Type [q or Q] to quit\n\n";

    using boost::spirit::ascii::space;
    typedef std::string::const_iterator iterator_type;
    typedef client::employee_parser<iterator_type> employee_parser;

    employee_parser g; // Our grammar
    std::string str;
    while (getline(std::cin, str))
    {
        if (str.empty() || str[0] == 'q' || str[0] == 'Q')
            break;

        client::employee emp;
        std::string::const_iterator iter = str.begin();
        std::string::const_iterator end = str.end();
        bool r = phrase_parse(iter, end, g, space, emp);

        if (r && iter == end)
        {
            std::cout << boost::fusion::tuple_open('[');
            std::cout << boost::fusion::tuple_close(']');
            std::cout << boost::fusion::tuple_delimiter(", ");

            std::cout << "-------------------------\n";
            std::cout << "Parsing succeeded\n";
            std::cout << "got: " << boost::fusion::as_vector(emp) << std::endl;
            std::cout << "\n-------------------------\n";
        }
        else
        {
            std::cout << "-------------------------\n";
            std::cout << "Parsing failed\n";
            std::cout << "-------------------------\n";
        }
    }

    std::cout << "Bye... :-) \n\n";
    return 0;
}