source code from: https://stackoverflow.com/questions/38043442/how-do-inline-variables-work
#include <iostream>
#include <string>
using namespace std;
struct Kath
{
static std::string const hi;
};
inline std::string const Kath::hi = "Zzzzz..."; // Simpler!
int main()
{
cout << Kath::hi << endl;
return 0;
}