Let us consider that you need to maintain about musicians in a data store. Among other things, you can look up the latest album released by an artiste. You have written a simple API in C++ for doing this:

std::string find_latest_album_of(const std::string& artisteName);

For simplicity we will ignore the possibility that two or more artistes could share the same name. Here is a simple implementation of this function:

 1 #include <string>
 2 #include <map>
 3
 4 typedef std::map<std::string, std::string> artiste_album_map;
 5
 6 extern artiste_album_map latest_albums;
 7
 8 std::string find_latest_album_of(
 9     ...