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Python Object-Oriented Python Dice Roller RPG Roller

Posted by Emily Strobl
Emily Strobl
5,429 Points

error

no matter what I do I keep getting an error saying that 'hand' doesn't have a 'roll' method.

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)


from dice import D20

class Hand(list):
    def __init__(self, size=None, die_class=20):
        super().__init__()
        for _ in range(size):
            self.append(die_class())   

    @property
    def total(self):
        return sum(self)
    @classmethod
    def roll(cls, size=2):
        return cls(size=2,die_class=D20)
hands.py 
class Hand(list):
    @property
    def total(self):
        return sum(self)

2 Answers

William Li
William Li
7,950 Points
William Li
William Li
7,950 Points

I think it works but you have to have the Hand class in the hands.py file.

Also you shouldn't set the die_class parameter to have a default value of 20 because that would give an error if that value was used.

Below is what I did for this challenge

from dice import *

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

    @classmethod
    def roll(cls,number_of_die):
        thing = cls()
        for _ in range(number_of_die):
            thing.append(D20())
        return thing
Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

Since "size" is defined as parameter, and given a default in the "def" line, it should be passed as-is in the call:

    def roll(cls, size=2):
        return cls(size, die_class=D20)

Otherwise, the code above appears that some of the "hands" code was copied into the "dice.py" file. Make sure that all the code related to "hands" is in the "hands.py" file.