Error including boost/spirit/include/qi.hpp

Question

I'm having the same error as occurs here. See 'compilation info' at the bottom for the long error message. Basically if I #include <boost/spirit/include/qi.hpp> I can't compile. Totally stumped by this one... I am compiling with g++ 4.9.3 on Debian using C++11. For reference the first part of the error message is:

In file included from /usr/include/boost/spirit/home/qi/nonterminal/rule.hpp:35:0,
             from /usr/include/boost/spirit/home/qi/nonterminal.hpp:14,
             from /usr/include/boost/spirit/home/qi.hpp:20,
             from /usr/include/boost/spirit/include/qi.hpp:16,
             from prog.cpp:9:
/usr/include/boost/spirit/home/qi/reference.hpp: In instantiation of 'bool boost::spirit::qi::reference<Subject>::parse(Iterator&, const Iterator&, Context&, const Skipper&, Attribute&) const [with Iterator = __gnu_cxx::__normal_iterator<char*, std::basic_string<char> >; Context = boost::spirit::context<boost::fusion::cons<std::basic_string<char>&, boost::fusion::nil_>, boost::spirit::locals<> >; Skipper = boost::spirit::qi::char_class<boost::spirit::tag::char_code<boost::spirit::tag::space, boost::spirit::char_encoding::ascii> >; Attribute = std::basic_string<char>; Subject = const boost::spirit::qi::rule<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, std::basic_string<char>(), boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal, boost::proto::argsns_::term<boost::spirit::tag::char_code<boost::spirit::tag::space, boost::spirit::char_encoding::ascii> >, 0l>, boost::spirit::unused_type, boost::spirit::unused_type>]':

My code is actually a little bit different to the above example:

My::Dictionary Parser::parse( const char * s ) {
  std::string input(s);     // input to parse
  qi_my_protocol grammar;   // create instance of parser
  My::Dictionary msg;      // map to receive results
  bool result = qi::phrase_parse(
    input.begin(),
    input.end(),
    grammar,
    qi::space,
    msg
  ); // returns true if successful
  return msg;
}

Answer 1

Your string isn't const, so the iterators first and last aren't const iterators.

Either make the my_Parse function not a template (after all, you hardcode the iterator type on the grammar to be std::string::const_iterator anyways), or instantiate the grammar with the actual iterator type:

my_grammar<Iterator> g;

Live On Coliru

#include <boost/spirit/include/qi.hpp>
#include <boost/spirit/include/phoenix.hpp>

#include <stdio.h>

namespace qi =       boost::spirit::qi;
namespace ascii =    boost::spirit::ascii;
namespace phoenix =  boost::phoenix;

template <typename Iterator>
struct my_grammar : boost::spirit::qi::grammar<Iterator, std::string(), ascii::space_type>
{

    my_grammar() : my_grammar::base_type(start)
    {
        using qi::alpha;
        using qi::alnum;

        start %=
            (+alpha | +alnum)
            ;
    }

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

template <typename Iterator>
bool my_Parse(Iterator first, Iterator last, std::string& result)
{
    using boost::spirit::ascii::space;

    my_grammar<Iterator> g;

    bool r = phrase_parse(first, last, g, space, result);

    if (!r || first != last) // fail if we did not get a full match
        return false;

    return r;
}



int main() {
    std::string str;
    while (getline(std::cin, str))
    {
        std::string result = "";
        if (my_Parse(str.begin(), str.end(), result))
        {
            std::cout << "-------------------------\n";
            std::cout << "Parsing succeeded\n";
            std::cout << "got: " << result << std::endl;
            std::cout << "\n-------------------------\n";
        }
        else
        {
            std::cout << "-------------------------\n";
            std::cout << "Parsing failed\n";
            std::cout << "-------------------------\n";
        }
    }
}