#include <stdio.h>                                              /* addToPoint.c */

typedef struct {
  double x, y;
 } Point;

void addToPoint(Point * p, const Point * d) /*@{}@XPC{structure pointers as @B {references}}*/
{ p->x += d->x;                                        /*@{}@XPC{@B {structure pointer dereferencing}:}*/
  p->y += d->y;                                        /*@{}@XPC{{}   @CP {p->x}  @CP style {symbol} {=  p->x  =  (*p).x}             {}}*/
}

int main() {
  Point p = {3.0, 4.0}, q = {1.2, 2.3};
  printf("p = (%f, %f)\n", p.x, p.y);
  addToPoint(&p, &q);                            /*@{}@XPC{structure references as arguments} */
  printf("p = (%f, %f)\n", p.x, p.y);
  return 0;
}