At 05:35 AM 7/13/2007, Tiger12506 wrote: > > ======================================= > > class BankAccount(object): > > def __init__(self, initial_balance=0): > > self.balance = initial_balance > > def deposit(self, amount): > > self.balance += amount > > def withdraw(self, amount): > > self.balance -= amount > > def overdrawn(self): > > return self.balance < 0 > > my_account = BankAccount(15) > > my_account.withdraw(5) > > print my_account.balance > > ========================================= > > > > This prints the expected "10". > > > > My question is, of what use can "overdrawn" be put? If I change the > > withdrawal amount to 25, it prints the expected "-10", whether the class > > contains the "overdrawn" function or not. > > > > Thanks, > > > > Dick Moores > >A very good question. Now I have one for you. What does your bank do when >you try to withdraw money? First, it checks to see if you have the money in >your account. If you do, it subtracts that out of your balance. Whoever >wrote that code failed to do the check within the withdraw function. > >======================================= >class BankAccount(object): > def __init__(self, initial_balance=0): > self.balance = initial_balance > def deposit(self, amount): > self.balance += amount > def withdraw(self, amount): > if self.overdrawn(): > raise "Insufficient Funds Error" > self.balance -= amount > def overdrawn(self): > return self.balance < 0 >my_account = BankAccount(15) >my_account.withdraw(5) >print my_account.balance >=========================================
But when I run that with a withdrawal of 25, it still prints only "-10". How have you involved the "overdrawn" function? Dick _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
