#include<string>
#include<iostream>
 
template <std::string * temp> //pointer to object
void f()
{
   std::cout << *temp << std::endl;
}
 
template <std::string & temp> //reference to object
void g()
{
     std::cout << temp << std::endl;
     temp += "...appended some string";
}
 
std::string s; //must not be local as it must have external linkage! WHY???
 
int main() {
        s = "can assign values locally";
        f<&s>();
        g<s>();
        std::cout << s << std::endl;
        return 0;
}

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