/******************************************************************************
 ***   FILE: error_flag.cpp
 ***   DATE: 03/17/2004
 *** AUTHOR: Daniel Dementiev
 ***   GOAL: This program illustrates how no litle error checking or can cause
 ***         a damage to the data. Pay attention to the method Array::Item()
 ***         we check that the value of the index argument is valid, but we
 ***         just set an error flag.
 ******************************************************************************/
#include <iostream>
using namespace std;

class Array {
   private:
      int count;
      int data[10];
      int size;
      bool error;
   public:
      Array() : count(0), size(10), error(false) {};
      int Count() const { return count; };
      int Size() const { return size; };
      bool Error();
      int& Item(int index);
};

int& Array::Item(int index)
{
   error = index<0 || index>=10 ;
   return data[index];
}

bool Array::Error()
{
   bool err = error;
   error = false;
   return err;
}


void main()
{
   Array a;
   cout<<"count = "<<a.Count()<<endl;
   cout<<" size = "<<a.Size()<<endl;
   a.Item(10) = 5;
   if( a.Error() ){
      cerr<<"An error has happened while calling Array::Item()\n";
      exit(1);
   }
   cout<<"After running 'a.Item(10) = 5':\n";
   cout<<"count = "<<a.Count()<<endl;
   cout<<" size = "<<a.Size()<<endl;
}