🔒 Classes

[sudden fable]

Im new to classes, how do pass my checks below

class Jar:
    def __init__(self, capacity=12):
        if capacity < 0:
            raise ValueError
        self.capacity = capacity


    def __str__(self):
        for n in self.capacity:
            return print(":cookie:", end=end)

    def deposit(self, n):
        n = input("add cookies to jar")
        self.capacity += n

        if self.capacity >= 12:
            raise ValueError

    def withdraw(self, n):
        ...

    @property
    def capacity(self):
        return print("12")

    @property
    def size(self):
        return print(self.capacity)

[rotund urchin]

@sudden fable

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[sudden fable]

not sure if my code is correct too

[indigo cosmos]

You’re mixing up a few concepts:

• capacity should be the maximum cookies the jar can hold.

• You also need to keep track of the current number of cookies (e.g. self._size).

• @property should return a value, not print something.

• str should return a string representation of the jar.
  here is a clean version:
  class Jar:
  def init(self, capacity=12):
  if capacity < 0:
  raise ValueError("Capacity cannot be negative")
  self._capacity = capacity
  self._size = 0 # current cookies in the jar

  def str(self):
  return "cookie" * self._size

  def deposit(self, n):
  if self._size + n > self.capacity:
  raise ValueError("Too many cookies for the jar")
  self._size += n

  def withdraw(self, n):
  if n > self._size:
  raise ValueError("Not enough cookies to withdraw")
  self._size -= n

  @property
  def capacity(self):
  return self._capacity

  @property
  def size(self):
  return self._size

[sudden fable]

ok thanks for the advice

when i first intialise jar, it should be empty

[vivid wave]

def __str__(self):
    for n in self.capacity:
        return print(":cookie:", end=end)

you're returning a print

do you information about what they expect you to return from __str__?

[sudden fable]

yes wait

str should return a str with 𝑛 🍪, where 𝑛 is the number of cookies in the cookie jar. For instance, if there are 3 cookies in the cookie jar, then str should return "🍪🍪🍪"

[vivid wave]

you don't need a loop to do that then

you can multiply a string

[sudden fable]

ait thx

and what if its empty?

[vivid wave]

any string multiplied by 0 will return an empty string

no special case needed

[sudden fable]

oh ok

thanks

[indigo cosmos]

Final version for str:
def str(self):
return "🍪" * self._size

[vivid wave]

Please don't post chat GPT responses

[sudden fable]

is it gpt?

[vivid wave]

100%

[sudden fable]

damn

assertion Error?

from jar import Jar


def test_init():
    ...


def test_str():
    jar = Jar()
    assert str(jar) == ""
    jar.deposit(1)
    assert str(jar) == "🍪"
    jar.deposit(11)
    assert str(jar) == "🍪🍪🍪🍪🍪🍪🍪🍪🍪🍪🍪🍪"


def test_deposit():
    ...


def test_withdraw():
    ...

my test

[vivid wave]

show your new class code

[sudden fable]

class Jar:
    def init(self, capacity=12):
        if capacity < 0:
            raise ValueError("Capacity cannot be negative")
        self.capacity = capacity
        self.size = 0  # current cookies in the jar

    def str(self):
        return "🍪" * self.size

    def deposit(self, n):
        if self._size + n > self.capacity:
            raise ValueError("Too many cookies for the jar")
        self._size += n

    def withdraw(self, n):
        if n > self.size:
            raise ValueError("Not enough cookies to withdraw")
        self._size -= n

    @property
    def capacity(self):
        return self.capacity

    @property
    def size(self):
        return self.size

[vivid wave]

you need __str__ for it to work

[indigo cosmos]

sorry, i didn't know it's not allowed

[vivid wave]

not def str

[sudden fable]

oh man

[vivid wave]

!rule 10

[rotund urchin]

Rules

10. Do not copy and paste answers from ChatGPT or similar AI tools.

[sudden fable]

am i not setting it here?

class Jar:
    def __init__(self, capacity=12):
        if capacity < 0:
            raise ValueError("Capacity cannot be negative")
        self.capacity = capacity
        self.size = 0  # current cookies in the jar

    def __str__(self):
        return "🍪" * self.size

    def deposit(self, n):
        if self._size + n > self.capacity:
            raise ValueError("Too many cookies for the jar")
        self._size += n

    def withdraw(self, n):
        if n > self.size:
            raise ValueError("Not enough cookies to withdraw")
        self._size -= n

    @property
    def capacity(self):
        return self.capacity

    @property
    def size(self):
        return self.size

[vivid wave]

you need to be using _ for your attributes since you're turning them into properies

otherwise they will overwrite each other

does it indicate what you're meant to use the properties for?

[sudden fable]

just returning capacity and size

not much

ok thanks

!close

[rotund urchin]

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