21 #define DECLARE_SINGLE_INSTANCE_BASE(className)       \  argument
23     static className& GetInstance();                  \
25     className(const className&) = delete;             \
26     className& operator= (const className&) = delete; \
27     className(className&&) = delete;                  \
28     className& operator= (className&&) = delete;      \
31 #define DECLARE_SINGLE_INSTANCE(className)  \  argument
32     DECLARE_SINGLE_INSTANCE_BASE(className) \
34     className() = default;                  \
35     ~className() = default;                 \
37 #define IMPLEMENT_SINGLE_INSTANCE(className) \  argument
38 className& className::GetInstance()          \
40     static auto instance = new className();  \