diff --git a/include/lua/bitmap.hpp b/include/lua/bitmap.hpp
index 12c0e7d4..46af7997 100644
--- a/include/lua/bitmap.hpp
+++ b/include/lua/bitmap.hpp
@@ -6,6 +6,7 @@
 #include <cstdint>
 #include "core/window.hpp"
 #include "library/framebuffer.hpp"
+#include "library/string.hpp"
 
 struct lua_bitmap
 {
@@ -14,6 +15,7 @@ struct lua_bitmap
 	size_t width;
 	size_t height;
 	std::vector<uint16_t> pixels;
+	std::string print();
 };
 
 struct lua_dbitmap
@@ -23,6 +25,7 @@ struct lua_dbitmap
 	size_t width;
 	size_t height;
 	std::vector<premultiplied_color> pixels;
+	std::string print();
 };
 
 struct lua_palette
@@ -31,6 +34,7 @@ struct lua_palette
 	lua_palette();
 	~lua_palette();
 	mutex* palette_mutex;
+	std::string print();
 };
 
 struct lua_loaded_bitmap
diff --git a/include/lua/internal.hpp b/include/lua/internal.hpp
index 88cd0ad4..aa30cbea 100644
--- a/include/lua/internal.hpp
+++ b/include/lua/internal.hpp
@@ -21,8 +21,16 @@ extern bool lua_booted_flag;
 extern uint64_t lua_idle_hook_time;
 extern uint64_t lua_timer_hook_time;
 
-std::list<std::string(*)(lua_State* LS, int index)>& userdata_recogn_fns();
+struct luaclass_methods
+{
+	bool (*is)(lua_State* LS, int index);
+	const std::string& (*name)();
+	std::string (*print)(lua_State* LS, int index);
+};
+
+std::list<luaclass_methods>& userdata_recogn_fns();
 std::string try_recognize_userdata(lua_State* LS, int index);
+std::string try_print_userdata(lua_State* LS, int index);
 
 template<typename T>
 T get_numeric_argument(lua_State* LS, unsigned argindex, const char* fname)
@@ -95,7 +103,11 @@ public:
 	lua_class(const std::string& _name)
 	{
 		name = _name;
-		userdata_recogn_fns().push_back(lua_class<T>::recognize);
+		luaclass_methods m;
+		m.is = lua_class<T>::is;
+		m.name = lua_class<T>::get_name;
+		m.print = lua_class<T>::print;
+		userdata_recogn_fns().push_back(m);
 	}
 
 	template<typename... U> T* _create(lua_State* LS, U... args)
@@ -235,6 +247,17 @@ badtype:
 	{
 		return objclass<T>()._pin(LS, arg, fname);
 	}
+
+	static const std::string& get_name()
+	{
+		return objclass<T>().name;
+	}
+
+	static std::string print(lua_State* LS, int index)
+	{
+		T* obj = get(LS, index, "__internal_print");
+		return obj->print();
+	}
 private:
 	static int dogc(lua_State* LS)
 	{
diff --git a/include/lua/unsaferewind.hpp b/include/lua/unsaferewind.hpp
index 0199f031..56842c8d 100644
--- a/include/lua/unsaferewind.hpp
+++ b/include/lua/unsaferewind.hpp
@@ -1,6 +1,8 @@
 #ifndef _lua__unsaferewind__hpp__included__
 #define _lua__unsaferewind__hpp__included__
 
+#include "library/string.hpp"
+
 struct lua_unsaferewind
 {
 	std::vector<char> state;
@@ -11,6 +13,10 @@ struct lua_unsaferewind
 	uint64_t ssecs;
 	std::vector<uint32_t> pollcounters;
 	std::vector<char> hostmemory;
+	std::string print()
+	{
+		return (stringfmt() << "to frame " << frame).str();
+	}
 };
 
 #endif
diff --git a/src/lua/core.cpp b/src/lua/core.cpp
index f3c785ec..b9829678 100644
--- a/src/lua/core.cpp
+++ b/src/lua/core.cpp
@@ -36,8 +36,8 @@ namespace
 			return (stringfmt() << "Thread:" << lua_topointer(LS, index)).str();
 			break;
 		case LUA_TUSERDATA:
-			return (stringfmt() << "Userdata<" << try_recognize_userdata(LS, index) << ">:"
-				<< lua_touserdata(LS, index)).str();
+			return (stringfmt() << "Userdata<" << try_recognize_userdata(LS, index) << "@"
+				<< lua_touserdata(LS, index) << ">:[" << try_print_userdata(LS, index) << "]").str();
 		case LUA_TTABLE: {
 			//Fun with recursion.
 			const void* ptr = lua_topointer(LS, index);
diff --git a/src/lua/gui-bitmap.cpp b/src/lua/gui-bitmap.cpp
index f1bdc097..076fe397 100644
--- a/src/lua/gui-bitmap.cpp
+++ b/src/lua/gui-bitmap.cpp
@@ -21,6 +21,11 @@ lua_bitmap::~lua_bitmap()
 	render_kill_request(this);
 }
 
+std::string lua_bitmap::print()
+{
+	return (stringfmt() << width << "*" << height).str();
+}
+
 lua_dbitmap::lua_dbitmap(uint32_t w, uint32_t h)
 {
 	width = w;
@@ -33,6 +38,11 @@ lua_dbitmap::~lua_dbitmap()
 	render_kill_request(this);
 }
 
+std::string lua_dbitmap::print()
+{
+	return (stringfmt() << width << "*" << height).str();
+}
+
 lua_palette::lua_palette()
 {
 	palette_mutex = &mutex::aquire();
@@ -43,6 +53,12 @@ lua_palette::~lua_palette()
 	delete palette_mutex;
 }
 
+std::string lua_palette::print()
+{
+	size_t s = colors.size();
+	return (stringfmt() << s << " " << ((s != 1) ? "colors" : "color")).str();
+}
+
 namespace
 {
 	struct render_object_bitmap : public render_object
diff --git a/src/lua/gui-text-cf.cpp b/src/lua/gui-text-cf.cpp
index dc187be7..3382bbfd 100644
--- a/src/lua/gui-text-cf.cpp
+++ b/src/lua/gui-text-cf.cpp
@@ -15,6 +15,10 @@ namespace
 		~lua_customfont() throw();
 		int draw(lua_State* LS);
 		const custom_font& get_font() { return font; }
+		std::string print()
+		{
+			return "";
+		}
 	private:
 		custom_font font;
 	};
diff --git a/src/lua/ibind.cpp b/src/lua/ibind.cpp
index da263830..ed7a083f 100644
--- a/src/lua/ibind.cpp
+++ b/src/lua/ibind.cpp
@@ -7,6 +7,10 @@ class lua_inverse_bind
 {
 public:
 	lua_inverse_bind(const std::string name, const std::string cmd);
+	std::string print()
+	{
+		return ikey.getname();
+	}
 private:
 	inverse_key ikey;
 };
diff --git a/src/lua/inputmovie.cpp b/src/lua/inputmovie.cpp
index 5d1ce24c..5d1dd926 100644
--- a/src/lua/inputmovie.cpp
+++ b/src/lua/inputmovie.cpp
@@ -72,6 +72,12 @@ namespace
 		{
 			return f;
 		}
+		std::string print()
+		{
+			char buf[MAX_SERIALIZED_SIZE];
+			f.serialize(buf);
+			return buf;
+		}
 	private:
 		short getbutton(unsigned port, unsigned controller, unsigned index)
 		{
@@ -531,6 +537,11 @@ namespace
 		{
 			return &v;
 		}
+		std::string print()
+		{
+			size_t s = v.size();
+			return (stringfmt() << s << " " << ((s != 1) ? "frames" : "frame")).str();
+		}
 	private:
 		void common_init(lua_State* L);
 		controller_frame_vector v;
diff --git a/src/lua/lua.cpp b/src/lua/lua.cpp
index 6913a448..033a117b 100644
--- a/src/lua/lua.cpp
+++ b/src/lua/lua.cpp
@@ -670,19 +670,17 @@ bool lua_do_once(lua_State* LS, void* key)
 	}
 }
 
-std::list<std::string(*)(lua_State* LS, int index)>& userdata_recogn_fns()
+std::list<luaclass_methods>& userdata_recogn_fns()
 {
-	static std::list<std::string(*)(lua_State* LS, int index)> x;
+	static std::list<luaclass_methods> x;
 	return x;
 }
 
 std::string try_recognize_userdata(lua_State* LS, int index)
 {
-	for(auto i : userdata_recogn_fns()) {
-		std::string x = i(LS, index);
-		if(x != "")
-			return x;
-	}
+	for(auto i : userdata_recogn_fns())
+		if(i.is(LS, index))
+			return i.name();
 	//Hack: Lua builtin file objects.
 	lua_pushstring(LS, "FILE*");
 	lua_rawget(LS, LUA_REGISTRYINDEX);
@@ -697,6 +695,14 @@ std::string try_recognize_userdata(lua_State* LS, int index)
 	return "unknown";
 }
 
+std::string try_print_userdata(lua_State* LS, int index)
+{
+	for(auto i : userdata_recogn_fns())
+		if(i.is(LS, index))
+			return i.print(LS, index);
+	return "no data available";
+}
+
 bool lua_requests_repaint = false;
 bool lua_requests_subframe_paint = false;
 bool lua_supported = true;
diff --git a/src/lua/memory.cpp b/src/lua/memory.cpp
index eb436e0f..b46a63bd 100644
--- a/src/lua/memory.cpp
+++ b/src/lua/memory.cpp
@@ -99,7 +99,11 @@ public:
 		x.first->write(LS, x.second);
 		return 0;
 	}
-
+	std::string print()
+	{
+		size_t s = mappings.size();
+		return (stringfmt() << s << " " << ((s != 1) ? "mappings" : "mapping")).str();
+	}
 	int map(lua_State* LS);
 private:
 	std::map<std::string, std::pair<mmap_base*, uint64_t>> mappings;