编译器对C++ 11变参模板（Variadic Template）的函数包扩展实现的差异

 1 #include <iostream>
 2 
 3 
 4 template <typename ... T>
 5 void dummy_wrapper(T... t)
 6 {
 7 };
 8 
 9 template <class T>
10 T unpacker(const T t)
11 {
12     std::cout << ‘[‘ << t << ‘]‘;
13     return t;
14 }
15 
16 
17 template <typename... Args>
18 void write_line(const Args& ... data)
19 {
20     dummy_wrapper(unpacker(data)...);
21     std::cout << ‘\n‘;
22 }
23 
24 int main()
25 {
26     write_line(1, "--", "2.2.2", "--", 3.0);
27     return 0;
28 }

 1 #include <iostream>
 2 
 3 template <typename ... Tlist>
 4 void dummy_wrapper(Tlist... tlst)
 5 {
 6 };
 7 
 8 template <typename T, typename ... Tlist>
 9 void dummy_wrapper(T t, Tlist... tlst)
10 {
11     unpacker(t);
12     dummy_wrapper(tlst...);
13 };
14 
15 template <class T>
16 T unpacker(const T t)
17 {
18     std::cout << ‘[‘ << t << ‘]‘;
19     return t;
20 }
21 
22 template <typename... Args>
23 void write_line(const Args& ... data)
24 {
25     dummy_wrapper(data...);
26     std::cout << ‘\n‘;
27 }
28 
29 int main()
30 {
31     write_line(1, "--", "2.2.2", "--", 3.0);
32     return 0;
33 }

 1 template<typename ret_type, 
 2     typename ...args_type>
 3 class g_functor_ret
 4 {
 5 public:
 6     static int invoke(lua_State *state)
 7     {
 8         void *upvalue_1 = lua_touserdata(state, lua_upvalueindex(1));
 9         ret_type(*fun_ptr)(args_type...) = (ret_type( *)(args_type...))(upvalue_1);
10         int para_idx = 0;
11         push_stack<ret_type>(state, fun_ptr(read_stack<args_type>(state, para_idx++)...));
12     }
13 };