#include <iostream> #include <vector> #include <thread> #include <string> #include <sstream> #include <utility> #include <type_traits> #include <boost/timer/timer.hpp> #include "variant.hpp" using namespace mapbox; namespace test { struct point { public: point (double x_, double y_) : x(x_), y(y_) {} double x; double y; }; struct line_string : std::vector<point> {}; struct polygon : std::vector<line_string> {}; using variant = util::variant<std::reference_wrapper<const point>, std::reference_wrapper<const line_string>, std::reference_wrapper<const polygon>>; struct print { using result_type = void; void operator() (point const& pt) const { std::cerr << "Point(" << pt.x << "," << pt.y << ")" << std::endl; } void operator() (line_string const& line) const { std::cerr << "Line("; for (auto const& pt : line) { std::cerr << pt.x << " " << pt.y << ","; } std::cerr << ")" << std::endl; } template <typename T> void operator() (T const& val) const { std::cerr << typeid(T).name() << std::endl; } }; } int main (int argc, char** argv) { std::cerr << sizeof(test::polygon) << std::endl; std::cerr << sizeof(test::variant) << std::endl; test::point pt(123,456); test::variant var = std::move(std::cref(pt)); util::apply_visitor(test::print(), var); test::line_string line; line.push_back(pt); line.push_back(pt); line.push_back(test::point(999,333)); var = std::move(std::cref(line)); util::apply_visitor(test::print(), var); std::cerr << "Is line (cref) ? " << var.is<std::reference_wrapper<test::line_string const>>() << std::endl; auto const& line2 = var.get<test::line_string>(); // accessing underlying type of std::reference_wrapper<T> test::print printer; printer(line2); return EXIT_SUCCESS; }