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Python Object-Oriented Python Dice Roller RPG Roller

Posted by MoatazBellah Ghobashy
MoatazBellah Ghobashy
9,518 Points

What the wrong in my code!!!

I tested my code on my local program and works fine but here keeps showing this message "Can't get the length of a Hand"

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

    @property
    def total(self):
        return sum(self)

3 Answers

Steven Parker
Steven Parker
229,608 Points
Steven Parker
Steven Parker
229,608 Points

The instructions say, " I'm going to use code similar to Hand.roll(2) ..."

The example showing the method being called directly on the class itself is a clue that this should be implemented as a class method instead of a normal instance method.

Also, your method doesn't currently return anything, and the challenge wants "to get back an instance of Hand with two D20s rolled in it."

MoatazBellah Ghobashy
MoatazBellah Ghobashy
9,518 Points

Thanks a lot :)

Mark Chesney
Mark Chesney
11,747 Points
Mark Chesney
Mark Chesney
11,747 Points

I don't know why this doesn't work (and the Treehouse Code Challenge just says 'try again'.) Can anyone help me please? Thank you.

hands.py

from dice import D20

class Hand(list):
    def __init__(self, size, die_class, *args, **kwargs):
        super().__init__()

    @property
    def total(self):
        return sum(self)

    @classmethod
    def roll(cls, size=2):
        for _ in range(size):
            self.append(D20())
        return cls(size, die_class)

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)
Steven Parker
Steven Parker
229,608 Points
Steven Parker
Steven Parker
229,608 Points

When you post a question as an "answer" to another question, only the folks who asked and answered the other one are likely to see it. To reach the entire student population, always create a new question.

Mark Chesney
Mark Chesney
11,747 Points
Mark Chesney
Mark Chesney
11,747 Points

Ah didn't realize that. Thank you much