Overloading new and delete : overload new operator « Operator Overloading « C++ Tutorial






#include <iostream>
#include <cstdlib>
#include <new>
using namespace std;
   
class loc {
  int longitude, latitude;
public:
  loc() {}
  loc(int lg, int lt) {
    longitude = lg;
    latitude = lt;
  }
   
  void show() {
    cout << longitude << " ";
    cout << latitude << "\n";
  }
   
  void *operator new(size_t size);
  void operator delete(void *p);
};
   
// new overloaded relative to loc.
void *loc::operator new(size_t size)
{
  void *p;
   
  cout << "In overloaded new.\n";
  p =  malloc(size);
  if(!p) {
    bad_alloc ba;
    throw ba;
  }
  return p;
}
   
// delete overloaded relative to loc.
void loc::operator delete(void *p)
{
  cout << "In overloaded delete.\n";
  free(p);
}
   
int main()
{
  loc *p1, *p2;
   
  try {
    p1 = new loc (10, 20);
  } catch (bad_alloc xa) {
    cout << "Allocation error for p1.\n";
    return 1;
  }
   
  try {
    p2 = new loc (-10, -20);
  } catch (bad_alloc xa) {
    cout << "Allocation error for p2.\n";
    return 1;;
  }
   
  p1->show();
  p2->show();
   
  delete p1;
  delete p2;
   
  return 0;
}








10.13.overload new operator
10.13.1.Overloaded 'new' operator relative to Point
10.13.2.Overloading new and delete
10.13.3.An example of overloading new and delete globally