输出结果如下：
X_type_count< int, _Ty... > : 2 tuple type : std::tuple< int, int, int, char, char, double > X_tuple_type_count< int > : 3 X_tuple_type_count< char > : 2 X_tuple_type_count< double > : 1 X_tuple_type_count< float > : 0 X_tuple_type_count< void * > : 0