// pair.cpp - demonstrate class templates
//            Example in Murray, C++ Strategies and Tactics,
//                               Addison-Wesley, 1993

// class pair packs a two objects into a container
// for transportation.  Can help a function return
// more than one object.

template <class L, class R> class pair {

  public:
    pair(const L& larg, const R&  rarg) : lft(larg), rgt(rarg) { }
       L  left() const { return lft; }
       R right() const { return rgt; }
    void  left(const L& larg) { lft = larg; }
    void right(const R& rarg) { rgt = rarg; }
  private:
    L lft;
    R rgt;
}

pair<int,double> funct(int x, double y) {

  pair<int,double> temp(2*x,x+y);
  return temp;
}

#include <iostream.h>

void main() {

  cout << "Demonstrating Template Classes - pair<L,R>\n"
       << "==========================================\n\n";
  int x = 3; double y = 5.555;

//  pair<int,double> myPair;    compiler won't generate default
//                              ctor because another ctor was
//                              defined.  See Stroustrup, pg 570
//  myPair = funct(x,y);        So this doesn't work

  cout << "  funct returned myPair("
       << funct(x,y).left()
       << ", "
       << funct(x,y).right()
       << ")" << endl<< endl;
}