// File: intcell.C
//
// Implementation of the IntCell class

#include <iostream.h>
#include <iomanip.h>
#include <stdlib.h>
#include "intcell.h"


//========================================================================
// "Local" functions
//

static void CrashOnNULL(void *, char *) ;

static void CrashOnNULL(void *ptr, char *mesg) {
   if (ptr == NULL) {
      cerr << "CrashOnNULL: " << mesg <<endl ;
      exit(1) ;
   }
}


//========================================================================
// Definition of IntCell member functions
//

int IntCell::idvar=0 ;


// Constructor with optional int parameter
//
IntCell::IntCell(int n /* =0 */)
:  data(n) {

#ifndef NDEBUG
   cerr << "IntCell: constructor, this=" << this << endl ;
#endif
}


// Destructor, virtual.
//
IntCell::~IntCell() {
#ifndef NDEBUG
   cerr << "IntCell: destructor, this=" << this << endl ;
#endif

}


// Make a copy of this cell and return a pointer to clone.
//
ListCell *IntCell::clone() const {
   IntCell *ptr = new IntCell(data) ;
   CrashOnNULL(ptr, "Out of memory in IntCell::clone()") ;
   return ptr ;
}


// Compare a ListCell with this IntCell
//
int IntCell::cmp(const ListCell& cell) const {

#ifndef NDEBUG
   cerr << "IntCell: compare function" << endl ;
#endif

   if (cell.id() != &IntCell::idvar) { // if not an IntCell
      return cell.id() < &IntCell::idvar ? 1 : -1 ;
   }

   IntCell *iptr = (IntCell *) &cell ;  // convert to IntCell pointer
   if (data < iptr->data) return -1 ;
   if (data == iptr->data) return 0 ;
   return 1 ;
}


// print an int, virtual.
//
void IntCell::print() const {
#ifndef NDEBUG
   cerr << "IntCell: print function" << endl ;
#endif

   cout << data << " " ;
}


// return address of idvar.
//
int *IntCell::id() const {
#ifndef NDEBUG
   cerr << "IntCell: id function" << endl ;
#endif

   return &IntCell::idvar ;
}