// Illustrates how a reference can be used for naming convenience. // A program with two versions of the function work_on_persons_road_number. #include #include using namespace std; typedef struct{ char road[15]; int roadNumber; char town[20]; } address; typedef struct{ int idNumber; char firstName[10], lastName[20]; address location;} person; bool even(int n){ return n%2 == 0; } // A function in which a long and deep field name is used many times. void work_on_persons_road_number(person &p){ if (even(p.location.roadNumber)) p.location.roadNumber = p.location.roadNumber + 1; else p.location.roadNumber = 0; } // A version of the function that binds the roadNumber field to an // int reference. void work_on_persons_road_number_with_ref(person &p){ int &lrn = p.location.roadNumber; if (even(lrn)) lrn = lrn + 1; else lrn = 0; } void print_person(person &p){ cout << p.firstName << " " << p.lastName << endl << p.location.road << " " << p.location.roadNumber << endl << p.location.town << endl << endl; } int main(){ person morten = {190583, /* Initializer */ "Morten", "Madsen", /* and only that... */ {"Bredgade", 23, "Middelfart"} }; print_person(morten); work_on_persons_road_number(morten); print_person(morten); work_on_persons_road_number_with_ref(morten); print_person(morten); }