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- /*=============================================================================
- 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 summing a comma-separated list of numbers using phoenix.
- //
- // [ JDG June 28, 2002 ] spirit1
- // [ JDG March 24, 2007 ] spirit2
- //
- ///////////////////////////////////////////////////////////////////////////////
- #include <boost/config/warning_disable.hpp>
- //[tutorial_adder_includes
- #include <boost/spirit/include/qi.hpp>
- #include <boost/spirit/include/phoenix_core.hpp>
- #include <boost/spirit/include/phoenix_operator.hpp>
- #include <iostream>
- #include <string>
- //]
- namespace client
- {
- //[tutorial_adder_using
- namespace qi = boost::spirit::qi;
- namespace ascii = boost::spirit::ascii;
- namespace phoenix = boost::phoenix;
- using qi::double_;
- using qi::_1;
- using ascii::space;
- using phoenix::ref;
- //]
- ///////////////////////////////////////////////////////////////////////////
- // Our adder
- ///////////////////////////////////////////////////////////////////////////
- //[tutorial_adder
- template <typename Iterator>
- bool adder(Iterator first, Iterator last, double& n)
- {
- bool r = qi::phrase_parse(first, last,
- // Begin grammar
- (
- double_[ref(n) = _1] >> *(',' >> double_[ref(n) += _1])
- )
- ,
- // End grammar
- space);
- if (first != last) // fail if we did not get a full match
- return false;
- return r;
- }
- //]
- }
- ////////////////////////////////////////////////////////////////////////////
- // Main program
- ////////////////////////////////////////////////////////////////////////////
- int
- main()
- {
- std::cout << "/////////////////////////////////////////////////////////\n\n";
- std::cout << "\t\tA parser for summing a list of numbers...\n\n";
- std::cout << "/////////////////////////////////////////////////////////\n\n";
- std::cout << "Give me a comma separated list of numbers.\n";
- std::cout << "The numbers are added using Phoenix.\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;
- double n;
- if (client::adder(str.begin(), str.end(), n))
- {
- std::cout << "-------------------------\n";
- std::cout << "Parsing succeeded\n";
- std::cout << str << " Parses OK: " << std::endl;
- std::cout << "sum = " << n;
- std::cout << "\n-------------------------\n";
- }
- else
- {
- std::cout << "-------------------------\n";
- std::cout << "Parsing failed\n";
- std::cout << "-------------------------\n";
- }
- }
- std::cout << "Bye... :-) \n\n";
- return 0;
- }
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