D20 Dice Challenge: Need help understand length issue, and positional argument 'rolls'

Question

Within the challenge I am getting some error message about not getting the length of roll, but I do not understand how to resolve.

From workspaces I tried to simulate the expected request so as to troubleshoot the issue from console

>> from hands import Hand

>> Hand.roll(2)

and i get the below error:

Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: roll() missing 1 required positional argument: 'rolls'

As I provided an argument for roll() and my method accounts for rolls, what am I missing?

dice.py

import random


class Die:
    def __init__(self, sides=2):
        if sides < 2:
            raise ValueError("Can't have fewer than two sides")
        self.sides = sides
        self.value = random.randint(1, sides)

    def __int__(self):
        return self.value

    def __add__(self, other):
        return int(self) + other

    def __radd__(self, other):
        return self + other

class D20(Die):
    def __init__(self):
        super().__init__(sides=20)

hands.py

from dice import D20

class Hand(list):
    @property
    def total(self):
        return sum(self)

    def roll(self, rolls):
        for _ in range(rolls):
            self.append(D20())

Answer 1 · 2018-04-20T05:50:11Z

April 20, 2018 5:50am

This challenge is a bit harder. Since the execution will be from the class Hand, a regular method will not work since an instance of the method hasn't been created yet. Best to use a classmethod. Since the challenge wants an instance returned, this classmethod should explicitly return an instance.

Use a @classmethod decorator. Code style suggests using "cls" in place of the usual "self"
Create an instance. Can be as simple as self = cls()
Your for loop should work OK as-is
return self as the instance

Post back if you need more help. Good luck!!

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cb123

cb123

D20 Dice Challenge: Need help understand length issue, and positional argument 'rolls'

1 Answer

Chris Freeman

Chris Freeman