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Python Object-Oriented Python Dice Roller RPG Roller

chaoyi wang
chaoyi wang
3,680 Points

need help with "can't get the length with Hand"

I tested the code in workspace and I can get the .total to work but I'm not sure why it won't allow me to pass..., please help!

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

    def __repr__(self):
        return str(self.value)

    def __len__(self):
        return len(self)
class D20(Die):
    def __init__(self, *args, **kwargs):
        super().__init__(sides=20, *args, **kwargs)
hands.py
from dice import D20

class Hand(list):
    def __init__(self, size=0, die_class=None, *args, **kwargs):
        if not die_class:
            raise ValueError("You must provide a die class")
        super().__init__()

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

2 Answers

Steven Parker
Steven Parker
231,275 Points

You've changed the instantiation of Hand so that it now requires a die_class argument. That wasn't part of the instructions, and the challenge is still expecting to be able to create an instance without providing that.

It's OK to override __init__ but only if you don't change the instantiation signature. It's also possible to solve this challenge by adding new code only to the roll method.

chaoyi wang
chaoyi wang
3,680 Points

Thank you very much for your quick answer, I will try to modify the code! Thanks again!

chaoyi wang
chaoyi wang
3,680 Points

I found another answer by Christian Mangeng on another opened topic, which actually works... @classmethod def roll(cls, number): return cls(size=number, die_class=D20)

Steven Parker
Steven Parker
231,275 Points

That's almost the same as what you have above, and still requires overriding __init__ (without changing the instantiation signature).