internal void pushObject(IntPtr luaState, object o, string metatable)
                {
                        int index;
                        int top = LuaDLL.lua_gettop(luaState);
                        // Pushes nil
                        if(o==null)
                        {
                                LuaDLL.lua_pushnil(luaState);
                                return;
                        }
                        // Object already in the list of Lua objects? Push the stored reference.
                        if((index=objects.IndexOf(o))!=-1)
                        {
// during the next call, lua's gc calls the __gc metafunction on "o", so control passes to a
// collectObject() method in another class, which removes it from the objects ArrayList
                                LuaDLL.luaL_getmetatable(luaState,"luaNet_objects");
                                LuaDLL.lua_rawgeti(luaState,-1,index);
                                LuaDLL.lua_remove(luaState,-2);
                                if(LuaDLL.lua_isnil(luaState,-1))
                                {
                                        // Our object got GCed mid-way through retrieving it from the cache.
                                        // We should have removed it from the cache, so let's go get it fresh
                                        LuaDLL.lua_settop(luaState, top);
                                        pushObject(luaState, o, metatable); // Gets our fresh variant
                                        return;
                                }
                                return;
                        }
                        // New object: inserts it in the list
                        for(int i=0;i<objects.Count;i++)
                                if(objects[i]==null)
                                {
                                        objects[i]=o;
                                        index=i;
                                        break;
                                }
                        if(index==-1) index=objects.Add(o);
                        pushNewObject(luaState,o,index,metatable);
                }