/*
  metptr.cpp

  Esimerkki metodi-osoittimista ja kontravarianssista.

  Erilaisia tapoja kutsua olion metodia.

  Vesa Lappalainen 22.1.2000

*/

class cTesti1 {
protected:
  int i;
public:
  cTesti1() { i = 0; }
  virtual void hommaa() {}
  virtual void aseta();
};

class cTesti2 : public cTesti1 {
public:
  virtual void aseta();
};

void cTesti1::aseta() {
  i = 1;
}

void cTesti2::aseta() {
  i = 2;
}

typedef void (cTesti1::*Pm1)();
typedef void (cTesti2::*Pm2)();

//---------------------------------------------------------------------------
#pragma argsused
cTesti1 t1;
cTesti2 t2;
Pm1 mp1;
Pm2 mp2;
cTesti1 *op1 =  &t1;
cTesti1 *op1a = &t2;
cTesti2 *op2 =  &t2;
int i;

int main(int argc, char* argv[])
{
  mp2 = &cTesti1::hommaa;
  mp1  = &cTesti1::aseta;
  mp1  = &cTesti1::aseta;


  i = sizeof(mp1);
  (op1->*mp1)();
  (op2->*mp2)();
  (op2->*mp1)();
  (t1.*mp1)();

  t1.aseta();
  op1->aseta();
  t2.aseta();
  op2->aseta();

  mp2 = mp1;
//  mp1 = mp2;  // ei toimi Kontravarianssi
  op1 = op2;
//  op2 = op1; // ei toimi
  op1->aseta();

  return 0;
}