If you want to force the programmer to keep string around, remove the 'const' from the function signature. The compiler will rigtly complain when you call the f

If you want to force the programmer to keep string around, remove the 'const' from the function signature. The compiler will rigtly complain when you call the function with a r-value as argument and will only accept l-values. l-values and r-values are the C++ way for dealing with this kind of situation. C++ has also some means to prevent from doing weird stuff.