Is it possible to write auto-cast operator outside a struct?

Question

The exact situation is next: I have defined in system API structs CGPoint and CGSize, and I want to be able to write my_point = my_size. I

Answer 1

Other answers seams to miss the obvious solution : add a function to convert CGPoint into CGSize. Off course, that is not exactly what you want (size = point), but since you can not modify either of two classes, this is the only way :

CGSize ToSize( const CGPoint &pt )
{
  CGSize res = ...
  // do the conversion
  return res;
}