C++ migration: templated lua_touserdata

1 files changed, 7 insertions, 0 deletions

diff --git a/src/macros_and_utils.h b/src/macros_and_utils.h
index c549d72..370cbed 100644
--- a/src/macros_and_utils.h
+++ b/src/macros_and_utils.h
@@ -124,3 +124,10 @@ inline void STACK_GROW(lua_State* L, int n_)
 }
 
 #define LUAG_FUNC( func_name) int LG_##func_name( lua_State* L)
+
+// a small helper to extract a userdata pointer from the stack
+template<typename T>
+T* lua_touserdata(lua_State* L, int index_)
+{
+    return static_cast<T*>(lua_touserdata(L, index_));
+}