#include <cstdlib>
#include <iostream>
#include <boost/spirit/home/qi.hpp>
#include <boost/spirit/home/support.hpp>
#include <boost/spirit/home/support/multi_pass.hpp>
#include <boost/spirit/home/support/iterators/detail/functor_input_policy.hpp>


class iterate_rnd {
private:
	size_t limit_;
public:
	typedef char result_type;

	static result_type eof;
	
	iterate_rnd() : limit_(104857600) {}
	iterate_rnd(size_t limit) : limit_(limit) {}

	result_type operator()() {
		if (limit_ == 0) return eof;
		limit_--;
		return rand() & 0x7F;
	}
};


iterate_rnd::result_type iterate_rnd::eof = iterate_rnd::result_type(-1);


using namespace boost::spirit;


typedef multi_pass<
	iterate_rnd,
	iterator_policies::default_policy<
		iterator_policies::ref_counted,
		iterator_policies::no_check,
		iterator_policies::functor_input,
		iterator_policies::split_std_deque
	>
> functor_multi_pass_type;


int main() {
	functor_multi_pass_type first = functor_multi_pass_type(iterate_rnd());
	functor_multi_pass_type last;
	std::string input;
	
	{
		functor_multi_pass_type copy(first);
		while (first != last) {
			++first;
		}
		std::cout << "Iterator offset at this point is " << std::distance(copy, first) << std::endl;
	}
	
	first.clear_queue();
	/* only one reference to the shared memory object is
	 * left, but no memory reset is triggered within the iterator */
	std::cout << "Press enter to exit. Check memory usage at this point.";
	std::getline(std::cin, input);
	
	return 0;
}