c++11 - Define global const variables known at run-time with helper functions (c++) -

i want define series of global variables within parametrise() helper function this:

// helper.h namespace settings {   extern const unsigned short something; } namespace helper {   void parametrise(int, char**); // parametrise command line using boost::program_options }  // main.cpp int main( int argc, char** argv) {   helper::parametrise(argc, argv);   return 0; }  // helper.cpp void helper::parametrise(int, char**) {   // parse input here   const unsigned short settings::something = .. // want } 

this code not compile of course, there has way around it.. or not?

you can make writable within translation unit, , have externally const, so:

// helper.h namespace settings {   extern const unsigned short& something; }  void parametrise(int, char**);  // helper.cpp namespace { namespace settings_internal {   unsigned short something; }}  namespace settings {   const unsigned short& = settings_internal::something; }  void parametrise(int, char**) { settings_internal::something = 123; }