Checking class equality
In the previous exercise, you defined a BankAccount
class with a number
attribute that was used for comparison. But if you were to compare a BankAccount
object to an object of another class that also has a number
attribute, you could end up with unexpected results.
For example, consider two classes
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Running acct == pn
will return True
, even though we're comparing a phone number with a bank account number.
It is good practice to check the class of objects passed to the __eq__()
method to make sure the comparison makes sense.
This is a part of the course
“Object-Oriented Programming in Python”
Exercise instructions
Both the Phone
and the BankAccount
classes have been defined. Try running the code as-is using the "Run code" button and examine the output.
- Modify the definition of
BankAccount
to only returnTrue
if thenumber
attribute is the same and thetype()
of both objects passed to it is the same.
Run the code and examine the output again.
Hands-on interactive exercise
Have a go at this exercise by completing this sample code.
class BankAccount:
def __init__(self, number, balance=0):
self.number, self.balance = number, balance
def withdraw(self, amount):
self.balance -= amount
# MODIFY to add a check for the type()
def __eq__(self, other):
return (self.number == other.number)
acct = BankAccount(873555333)
pn = Phone(873555333)
print(acct == pn)