cs Oct 23

Class Enumeration v/s Plain Enumeration

Month::jan

Month m = jan;

enum class Month, have to always use Month::jan , scope to use

enum Month

FINAL : given enum for Month do an operloading for the ++ operator.

lab5.cpp.pdf has a dependency on CreditCards.tex

after every operation , do a check_invariant..

credit_cards.cpp

#include "credit_cards.h"
#include <stdexcept>

bool CreditCards::invariant_violation()
{
   bool r = (coomonlimit != 1000 and  ..;
  for (CreditCard* x: cards) if (x->limit !=  commonlimit) r = true; // r should be true ?
  return r;
}

CreditCards::CreditCards(unsigned int limit)
:commonlimit(limit)
{
  if (invariant_violation()) throw std::runtime_error("invariant violation");
}

void CreditCards::add(CreditCard* c)
{
    if(cards.find(c) ! = cards.end()) throw std::runtime_error("pre-condition violation");
  cards.insert(c);
  if (invariant_violation()) throw std::runtime_error("invariant violation");

}

void CreditCards::card_delete(CreditCard* c)
{
   if (invariant_violation()) throw std::runtime_error("invariant violation");
}

void CreditCards::withdraw(CreditCard* c, unsigned int)
{
   if (invariant_violation()) throw std::runtime_error("invariant violation");
}

void CreditCards::deposit(CreditCard* c, unsigned int)
{
   if (invariant_violation()) throw std::runtime_error("invariant violation");
}

void CreditCards::withdrawAvail(CreditCard* c)
{
   if (invariant_violation()) throw std::runtime_error("invariant violation");
}

CreditCars cc(3000); fail_("should be failed to create cc with invalid limit");
catch(runtime_error) {succeed_(); }
try(CreditCards cc(5000); succeed_(); }
catch(runtime_error) { fail_("should not have failed to create cc with valid limit");}
 CreditCard c1(1000);
 CreditCards cc(2000);
 try(cc.add(&c1); fail_("illegal to have different limit");} catch(){succeed_();}
 CreditCard c2(2000);
 try(cc.add(&c2); succeed_();}fail_("illegal to have different limit");} catch(){succeed_();}