#include <forward_list>

int main (){
std::forward_list< std::pair<int,char> > mylist;

auto it = mylist.before_begin();

it = mylist.emplace_after ( it, 100, 'x' );
it = mylist.emplace_after ( it, 200, 'y' );
it = mylist.emplace_after ( it, 300, 'z' );

std::cout << "mylist contains:";
for (auto& x : mylist)
     std::cout << " (" << x.first << "," << x.second << ")";

std::cout << 'n';
return 0;
}