C++单例

 template<class T>
 class Singleton
 {
 public:
     using object_type = T;
     struct object_creator
     {
         object_creator()
         {
             Singleton<T>::instance();
         }
     };

     static object_creator creator_object;
 public:
     static object_type* instance()
     {
         static object_type _instance;
         return(&_instance);
     }
 };
 template<typename T> typename Singleton<T>::object_creator Singleton<T>::creator_object;