static object c++ "does not name a type" -

i have following code:

// header.h class outer   {          class mid         {            mid();           ~mid ();         };         class inner        {            private:                static mid m_mid;        };    }; 

when define static private object in cpp file, gives me error saying mid not name type:

 // header.cpp:   # include "header.h"   mid mid::m_mid;  {begin definitions outer, mid , inner here} 

any clue why compiler complain ? : mid not name type

there no class mid; there no member of mid named m_mid.

there is, however, class outer::mid, , class outer::inner has member named m_mid. write instead. :)

outer::mid outer::inner::m_mid;