From 945e435ad521734ddebc2c88a5a56acf6f71af26 Mon Sep 17 00:00:00 2001
From: Vraiment <jemc44@gmail.com>
Date: Sun, 23 Jul 2017 12:59:14 -0700
Subject: [PATCH] Changed event polling functions from templates to use
 std::function

---
 SDL2pp/EventPolling.cc     | 19 +++++++++++++++
 SDL2pp/EventPolling.hh     | 47 ++++++++++++++++++++++++--------------
 tests/test_eventpolling.cc |  4 ++--
 3 files changed, 51 insertions(+), 19 deletions(-)

diff --git a/SDL2pp/EventPolling.cc b/SDL2pp/EventPolling.cc
index 06b684d..9df99a6 100644
--- a/SDL2pp/EventPolling.cc
+++ b/SDL2pp/EventPolling.cc
@@ -21,6 +21,8 @@
 
 #include <SDL2pp/EventPolling.hh>
 
+using std::function;
+
 namespace SDL2pp {
 	namespace Event {
 		bool PollEvent() {
@@ -30,6 +32,17 @@ namespace SDL2pp {
 			return result;
 		}
 		
+		bool PollEvent(function<void(const SDL_Event &)> eventHandler) {
+			SDL_Event event;
+			if (!SDL_PollEvent(&event)) {
+				return false;
+			}
+			
+			eventHandler(event);
+			
+			return true;
+		}
+		
 		int PollAllEvents() {
 			int result;
 			
@@ -37,5 +50,11 @@ namespace SDL2pp {
 			
 			return result;
 		}
+		
+		int PollAllEvents(function<void(const SDL_Event &)> eventHandler) {
+			int result;
+			for (result = 0; PollEvent(eventHandler); result++);
+			return result;
+		}
 	}
 }
diff --git a/SDL2pp/EventPolling.hh b/SDL2pp/EventPolling.hh
index 16b0613..eed2d2b 100644
--- a/SDL2pp/EventPolling.hh
+++ b/SDL2pp/EventPolling.hh
@@ -26,6 +26,8 @@
 
 #include <SDL2pp/Export.hh>
 
+#include <functional>
+
 namespace SDL2pp {
 	namespace Event {
 		////////////////////////////////////////////////////////////
@@ -56,6 +58,19 @@ namespace SDL2pp {
 		/// retrieved the event handler is not called and this function
 		/// returns false.
 		///
+		/// This function accepts free functions, lambdas and callable objects.
+		///
+		/// If an instance of a callable struct/class needs to be passed
+		/// by reference, std::ref() needs to be used:
+		/// \code
+		/// struct EventHandler {
+		///     void operator()(const SDL_Event &);
+		/// };
+		///
+		/// EventHandler myEventHandler;
+		/// PollEvent(std::ref(myEventHandler));
+		/// \endcode
+		///
 		/// \ingroup events
 		///
 		/// \headerfile SDL2pp/EventPolling.hh
@@ -69,17 +84,7 @@ namespace SDL2pp {
 		/// \see https://wiki.libsdl.org/SDL_PollEvent
 		///
 		////////////////////////////////////////////////////////////
-		template <typename T>
-		bool PollEvent(T&& eventHandler) {
-			SDL_Event event;
-			if (!SDL_PollEvent(&event)) {
-				return false;
-			}
-			
-			eventHandler(event);
-			
-			return true;
-		}
+		SDL2PP_EXPORT bool PollEvent(std::function<void(const SDL_Event &)> eventHandler);
 		
 		////////////////////////////////////////////////////////////
 		/// \brief Polls all the events from the event queue
@@ -106,6 +111,19 @@ namespace SDL2pp {
 		/// using the polled event as an argument. This function returns the
 		/// amount of events that were polled.
 		///
+		/// This function accepts free functions, lambdas and callable objects.
+		///
+		/// If an instance of a callable struct/class needs to be passed
+		/// by reference, std::ref() needs to be used:
+		/// \code
+		/// struct EventHandler {
+		///     void operator()(const SDL_Event &);
+		/// };
+		///
+		/// EventHandler myEventHandler;
+		/// PollAllEvents(std::ref(myEventHandler));
+		/// \endcode
+		///
 		/// \ingroup events
 		///
 		/// \headerfile SDL2pp/EventPolling.hh
@@ -119,12 +137,7 @@ namespace SDL2pp {
 		/// \see https://wiki.libsdl.org/SDL_PollEvent
 		///
 		////////////////////////////////////////////////////////////
-		template <typename T>
-		int PollAllEvents(T&& eventHandler) {
-			int result;
-			for (result = 0; PollEvent(eventHandler); result++);
-			return result;
-		}
+		SDL2PP_EXPORT int PollAllEvents(std::function<void(const SDL_Event &)> eventHandler);
 	}
 }
 
diff --git a/tests/test_eventpolling.cc b/tests/test_eventpolling.cc
index 66e4451..a7a662e 100644
--- a/tests/test_eventpolling.cc
+++ b/tests/test_eventpolling.cc
@@ -101,7 +101,7 @@ BEGIN_TEST(int, char*[])
 		
 		const SDL_Event expectedEvent = PushUserEvent(45);
 		
-		EXPECT_TRUE(PollEvent(eventHandler) == true);
+		EXPECT_TRUE(PollEvent(std::ref(eventHandler)) == true);
 		EXPECT_TRUE(eventHandler.events.size() == 1);
 		
 		const SDL_Event result = eventHandler.events[0];
@@ -195,7 +195,7 @@ BEGIN_TEST(int, char*[])
 		}
 		int totalExpectedEvents = static_cast<int>(expectedEvents.size());
 		
-		EXPECT_TRUE(PollAllEvents(eventHandler) == totalExpectedEvents);
+		EXPECT_TRUE(PollAllEvents(std::ref(eventHandler)) == totalExpectedEvents);
 		EXPECT_TRUE(eventHandler.events.size() == expectedEvents.size());
 		
 		for (int n = 0; n < totalExpectedEvents; n++) {