#include <boost/spirit/spirit.hpp>
#include <iostream>

///////////////////////////////////////////////////////////////
namespace spirit {

    //  This will be available in spirit V1.3

    template <typename DerivedT>
    struct grammar : public parser<grammar<DerivedT> > {

        template <typename IteratorT>
        match
        parse(IteratorT& first, IteratorT const& last) const
        {
            static typename DerivedT::definition<IteratorT> def;
            return def.start().parse(first, last);
        }
    };
}

using namespace spirit;
using namespace std;

///////////////////////////////////////////////////////////////////////////////

namespace {

    void    doInt(char const* str, char const* end)
    {
        string  s(str, end);
        cout << s << endl;
    }

    void    doAdd(char const*, char const*)     { cout << "ADD\n"; }
    void    doSubt(char const*, char const*)    { cout << "SUBT\n"; }
    void    doMult(char const*, char const*)    { cout << "MULT\n"; }
    void    doDiv(char const*, char const*)     { cout << "DIV\n"; }
}

///////////////////////////////////////////////////////////////
struct my_grammar : public grammar<my_grammar> {

    template <typename IteratorT>
    struct definition {

        rule<IteratorT>  expr, integer, group, expr1, expr2;

        definition()
        {
            integer = lexeme[ (!(ch_p('+') | '-') >> +digit)[&doInt] ];
            group   = '(' >> expr >> ')';
            expr1   = integer | group;
            expr2   = expr1 >> *(('*' >> expr1)[&doMult] | ('/' >> expr1)[&doDiv]);
            expr    = expr2 >> *(('+' >> expr2)[&doAdd] | ('-' >> expr2)[&doSubt]);
        }

        rule<IteratorT> const&
        start() const
        {
            return expr;
        }
    };
};

int
main()
{
    cout << "/////////////////////////////////////////////////////////\n\n";
    cout << "\t\tGrammar demonstration...\n\n";
    cout << "/////////////////////////////////////////////////////////\n\n";
    cout << "Type an expression...or [q or Q] to quit\n\n";

    my_grammar  g;

    while (true)
    {
        char str[256];
        cin.getline(str, 256);
        if (str[0] == 'q' || str[0] == 'Q')
            break;

        if (parse(str, g, space).full)
            cout << "parsing succeeded\n";
        else
            cout << "parsing failed\n";
    }

    return 0;
}