Question

I recently wrote some spirit parsing code in windows, which I recently have tried to get build on an ubuntu box and have ran into a compilation error that I am struggling with.

After some hacking and slashing, I have managed to come up with this example code snippet which exhibits the same behavior:

struct FooParser
: spirit::qi::grammar<
    std::string::const_iterator, 
    double(), 
    spirit::qi::ascii::space_type>
{
    FooParser() : FooParser::base_type(a_rule)
    {
        using namespace boost::spirit::qi;
        a_rule = double_;
    }

    spirit::qi::rule<
        string::const_iterator,
        double(),
        spirit::qi::ascii::space_type> a_rule;
};

which is then passed to a phrase_parse like so:

double result;
std::string txt;
FooParser foobar;
//...
if(phrase_parse(txt.begin(), txt.end(), foobar, space, result))
{
//do something
}

And when compiled, generates the following error:

boost/spirit/home/qi/reference.hpp:41: error: no matching function for call to 
‘boost::spirit::qi::rule<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char,
 std::char_traits<char>, std::allocator<char> > >, double(), 
boost::proto::exprns_::expr<boost::proto::tag::terminal, 
boost::proto::argsns_::term<boost::spirit::tag::char_code<boost::spirit::tag::space, 
boost::spirit::char_encoding::ascii> >, 0l>, boost::fusion::unused_type, 
boost::fusion::unused_type>::parse(__gnu_cxx::__normal_iterator<char*, 
std::basic_string<char, std::char_traits<char>, std::allocator<char> > >&, const 
__gnu_cxx::__normal_iterator<char*, std::basic_string<char, std::char_traits<char>, 
std::allocator<char> > >&, const boost::fusion::unused_type&, const 
boost::spirit::qi::char_class<boost::spirit::tag::char_code<boost::spirit::tag::space, 
boost::spirit::char_encoding::ascii> >&, double&) const’

The thing that I find frustrating is that visual studio seems more than happy to compile and run the code. I am hoping that the wise internets can show me where I have erred.

Answer 1

I think the problem here is the begin() and end() of std::string, try this:

std::string::const_iterator begin = txt.begin();
std::string::const_iterator end = txt.end();

then pass that in:

phrase_parse(begin, end, foobar, space, result)

The problem I believe is that everywhere else you are using the type const_iterator, but begin(), end() on a non const string returns a normal iterator.

The key part of the error is this bit:

parse(__gnu_cxx::__normal_iterator, std::allocator > >&, const
__gnu_cxx::__normal_iterator,
std::allocator > >&