You can not, it is by design. You should use a persistent variable (technique from the MATLAB as 1980 applied in year 2011)! For completeness I should mention that actually there is as of 2010b an undocumented and probably not longer supported static property modifier. For background see here the answer of Dave Foti, MATLAB … Read more
Section 11.5 “The C++ Programming Language” by Bjarne Stroustrup states that ordinary member functions get 3 things: access to internals of class are in the scope of the class must be invoked on an instance friends get only 1. static functions get 1 and 2.
You’re basically referring to the section ยง7.3.1.1/2 from the C++03 Standard, The use of the static keyword is deprecated when declaring objects in a namespace scope; the unnamed-namespace provides a superior alternative. Note that this paragraph was already removed in C++11. static functions are per standard no longer deprecated! Nonetheless, unnamed namespace‘s are superior to … Read more