can new[] call a customized constructor ? Howto make a union of pointers on arrays ?

[lalebarde]

Hi all,
can new[] call a customized constructor ?
In addition, I would like to do something like this, a kind of union of pointers :

class MyPointer {
public:
  MyPointer(int aClassId) : mClassId(aClassId) {};
  operatornew[]();
  Class0& operator*() {return *ptr0;}
  Class0* operator->() {return ptr0;}
  Class0& operator[](int aN) {return ptr0[aN];}
  Class1& operator*() {return *ptr1;}
  Class1* operator->() {return ptr1;}
  Class1& operator[](int aN) {return ptr1[aN];}
private:
  int mClassId;
  Class0* ptr0;
  Class1* ptr1;
}

MyPointer::operatornew[](size_t aSize) {
  switch (mClassId) {
    case 0 : {
      ptr0 = new Class0[aSize];
      break;
    }
    case 1 : {
      ptr1 = new Class1[aSize];
      break;
    }
  }
}

Any advice is welcome.

the alternative I use today but which is very unconveniant is to have a voi* pointer and to have if/else with static_cast of the pointers !!!

[kbw]

If you use this thing with a Class0*, but you've constructed a Class1*, there's no compile time check that you're doing the wrong thing. This is not the sort of problem you want to defer until runtime to discover.