20 #define WM_DECLARE_SINGLE_INSTANCE_BASE(className)          \  argument
22     static className& GetInstance();                        \
23     className(const className&) = delete;                   \
24     className& operator= (const className&) = delete;       \
25     className(className&&) = delete;                        \
26     className& operator= (className&&) = delete;            \
28 #define WM_DECLARE_SINGLE_INSTANCE(className)  \  argument
29     WM_DECLARE_SINGLE_INSTANCE_BASE(className) \
31     className() = default;                     \
32     virtual ~className() = default;            \
34 #define WM_IMPLEMENT_SINGLE_INSTANCE(className) \  argument
35 className& className::GetInstance()             \
37     static className instance;                  \