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- /*=============================================================================
- Copyright (c) 2001-2011 Hartmut Kaiser
- http://spirit.sourceforge.net/
- 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)
- =============================================================================*/
- //[porting_guide_classic_includes
- #include <boost/spirit/include/classic.hpp>
- #include <boost/spirit/include/phoenix1.hpp>
- #include <iostream>
- #include <string>
- //]
- //[porting_guide_classic_namespace
- using namespace boost::spirit::classic;
- //]
- //[porting_guide_classic_grammar
- struct roman : public grammar<roman>
- {
- template <typename ScannerT>
- struct definition
- {
- definition(roman const& self)
- {
- hundreds.add
- ("C" , 100)("CC" , 200)("CCC" , 300)("CD" , 400)("D" , 500)
- ("DC" , 600)("DCC" , 700)("DCCC" , 800)("CM" , 900) ;
- tens.add
- ("X" , 10)("XX" , 20)("XXX" , 30)("XL" , 40)("L" , 50)
- ("LX" , 60)("LXX" , 70)("LXXX" , 80)("XC" , 90) ;
- ones.add
- ("I" , 1)("II" , 2)("III" , 3)("IV" , 4)("V" , 5)
- ("VI" , 6)("VII" , 7)("VIII" , 8)("IX" , 9) ;
- first = eps_p [phoenix::var(self.r) = phoenix::val(0)]
- >> ( +ch_p('M') [phoenix::var(self.r) += phoenix::val(1000)]
- || hundreds [phoenix::var(self.r) += phoenix::_1]
- || tens [phoenix::var(self.r) += phoenix::_1]
- || ones [phoenix::var(self.r) += phoenix::_1]
- ) ;
- }
- rule<ScannerT> first;
- symbols<unsigned> hundreds;
- symbols<unsigned> tens;
- symbols<unsigned> ones;
- rule<ScannerT> const& start() const { return first; }
- };
- roman(unsigned& r_) : r(r_) {}
- unsigned& r;
- };
- //]
- int main()
- {
- {
- //[porting_guide_classic_parse
- std::string input("1,1");
- parse_info<std::string::iterator> pi = parse(input.begin(), input.end(), int_p);
- if (pi.hit)
- std::cout << "successful match!\n";
- if (pi.full)
- std::cout << "full match!\n";
- else
- std::cout << "stopped at: " << std::string(pi.stop, input.end()) << "\n";
- std::cout << "matched length: " << pi.length << "\n";
- //]
- }
- {
- //[porting_guide_classic_phrase_parse
- std::string input(" 1, 1");
- parse_info<std::string::iterator> pi = parse(input.begin(), input.end(), int_p, space_p);
- if (pi.hit)
- std::cout << "successful match!\n";
- if (pi.full)
- std::cout << "full match!\n";
- else
- std::cout << "stopped at: " << std::string(pi.stop, input.end()) << "\n";
- std::cout << "matched length: " << pi.length << "\n";
- //]
- }
- {
- //[porting_guide_classic_use_grammar
- std::string input("MMIX"); // MMIX == 2009
- unsigned value = 0;
- roman r(value);
- parse_info<std::string::iterator> pi = parse(input.begin(), input.end(), r);
- if (pi.hit)
- std::cout << "successfully matched: " << value << "\n";
- //]
- }
- return 0;
- }
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