///////////////////////////////////////////////////////////////
//  basic2.cpp - declare generic class, create & use objects //
//  ver 2                                                    //
//  Jim Fawcett, CSE687, S99                                 //
///////////////////////////////////////////////////////////////

#include <iostream>
using namespace std;

template<class T> class basic {

  public:
    basic(const char *inMsg, const T t);
    ~basic();
    void showMsg() const;   // const member functions don't 
                            // change object's state
  private:
    char* pMsg;
    T param;

  // make these private and unimplemented so copying and 
  // assignment are prohibited, even by members of this class
    basic(const basic &b);
    basic& operator=(const basic &b);
};

//----< constructor >--------------------------------------------

template <class T>
basic<T>::basic(const char *inMsg, const T t) : param(t)  {

  std::cout << "\n  constructing object\n";
  pMsg = new char[strlen(inMsg)+1];
  if(!pMsg)
    throw "\n  memory allocation failure\n\n";
  strcpy(pMsg,inMsg);  
}

//----< destructor >-------------------------------------------

template <class T>
basic<T>::~basic() {
  
  delete [] pMsg;
  std::cout << "\n  destroying object\n"; 
}

//---< display - show message >--------------------------------

template <class T>
void basic<T>::showMsg() const {
      cout << "  " << pMsg << " " << param << "\n";
}

//----< test >-------------------------------------------------

// Note: This global function must be template and must pass by
//       reference since copying is prohibited.

template <class T>
void caller(const basic<T> &b) {

  cout << "\n  caller using reference to basic object\n";
  b.showMsg();
}

void main() {

  std::cout << "\n  Demonstrate Basic Template Class Operation "
            << "\n ============================================\n";

  basic<int> myObj1("first object has param ", -7);
  myObj1.showMsg();

  basic<double> myObj2("second object has param ", 3.33e-33);
  myObj2.showMsg();

  basic<char> myObj3("third object has param ", 'z');
  myObj3.showMsg();

  caller(myObj1);
}