Boost.Spirit test

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

using namespace std;
using namespace boost::spirit;
namespace phx = boost::phoenix;

struct Test
{
	void func1() { cout << "func1()\n"; }
	void func2() { cout << "func2()\n"; }
	void func3() { cout << "func3()\n"; }
	void func4() { cout << "func4()\n"; }
};

template <typename Clazz>
void helper(Clazz& p, void (Clazz::*func)())
{
	(p.*func)();
}

template<typename Iterator>
struct MyGrammar : public qi::grammar<Iterator, ascii::space_type>
{
	typedef void (Test::*TestFunc)();
	qi::rule<Iterator, ascii::space_type> rule_;
	qi::rule<Iterator, Test* (), ascii::space_type> creator_;
	qi::rule<Iterator, TestFunc (), ascii::space_type> selector_;

	MyGrammar() : MyGrammar::base_type(rule_)
	{
		rule_ = creator_;

		creator_ =
			lit("test")     [_val = phx::new_<Test>()]
			>> selector_    [phx::bind(&helper<Test>, *_val, qi::_1)]
			// !!NG!!
			// >> selector_	[phx::bind(qi::_1, _val)]
			;

		selector_ =
			lit("1")        [_val = &Test::func1]
			| lit("2")      [_val = &Test::func2]
			| lit("3")      [_val = &Test::func3]
			| lit("4")      [_val = &Test::func4]
			;
	}
};

int main(int argc, char** argv)
{
	if (argc != 2) {
		cout << "invalid argument\n";
		return 1;
	}
	string str = argv[1];

	MyGrammar<string::iterator> syntax;
	if (!qi::phrase_parse(str.begin(), str.end(), syntax, ascii::space))
		cout << "syntax error\n";
}