Enable for_each_point with custom point type

Author: jfirebaugh

include/mapbox/geometry/for_each_point.hpp

@@ -4,48 +4,38 @@
 
 namespace mapbox { namespace geometry {
 
-// const
-
-template <typename T, typename F>
-void for_each_point(point<T> const& point, F&& f)
+template <typename Point, typename F>
+auto for_each_point(Point&& point, F&& f)
+    -> decltype(point.x, point.y, void())
 {
-    f(point);
-}
-
-template <typename...Types, typename F>
-void for_each_point(mapbox::util::variant<Types...> const& geom, F&& f)
-{
-    mapbox::util::variant<Types...>::visit(geom, [&] (auto const& g) { for_each_point(g, f); });
+    f(std::forward<Point>(point));
 }
 
 template <typename Container, typename F>
-auto for_each_point(Container const& container, F&& f)
-    -> decltype(container.begin(), container.end(), void())
-{
-    for (auto const& e: container) {
-        for_each_point(e, f);
-    }
-}
+auto for_each_point(Container&& container, F&& f)
+    -> decltype(container.begin(), container.end(), void());
 
-// mutable
-
-template <typename T, typename F>
-void for_each_point(point<T> & point, F&& f)
+template <typename...Types, typename F>
+void for_each_point(mapbox::util::variant<Types...> const& geom, F&& f)
 {
-    f(point);
+    mapbox::util::variant<Types...>::visit(geom, [&] (auto const& g) {
+        for_each_point(g, f);
+    });
 }
 
 template <typename...Types, typename F>
 void for_each_point(mapbox::util::variant<Types...> & geom, F&& f)
 {
-    mapbox::util::variant<Types...>::visit(geom, [&] (auto & g) { for_each_point(g, f); });
+    mapbox::util::variant<Types...>::visit(geom, [&] (auto & g) {
+        for_each_point(g, f);
+    });
 }
 
 template <typename Container, typename F>
-auto for_each_point(Container & container, F&& f)
+auto for_each_point(Container&& container, F&& f)
     -> decltype(container.begin(), container.end(), void())
 {
-    for (auto & e: container) {
+    for (auto& e: container) {
         for_each_point(e, f);
     }
 }

tests/test.cpp

@@ -136,12 +136,13 @@ static void testFeatureCollection() {
     assert(fc1.size() == 0);
 }
 
-static void testForEachPoint() {
-    struct point_counter {
-        std::size_t count = 0;
-        void operator()(point<double> const&) { count++; };
-    };
+struct point_counter {
+    std::size_t count = 0;
+    template <class Point>
+    void operator()(Point const&) { count++; };
+};
 
+static void testForEachPoint() {
     auto count_points = [] (auto const& g) {
         point_counter counter;
         for_each_point(g, counter);
@@ -169,6 +170,14 @@ static void testForEachPoint() {
     // Custom geometry type
     using my_geometry = mapbox::util::variant<point<double>>;
     assert(count_points(my_geometry(point<double>())) == 1);
+
+    // Custom point type
+    struct my_point {
+        int16_t x;
+        int16_t y;
+    };
+    assert(count_points(std::vector<my_point>({my_point{0, 1}})) == 1);
+    assert(count_points(mapbox::util::variant<my_point>(my_point{0, 1})) == 1);
 }
 
 static void testEnvelope() {