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Python Object-Oriented Python Dice Roller RPG Roller

Gokul Nishanth
PLUS
Gokul Nishanth
Courses Plus Student 581 Points
Posted by Gokul Nishanth
Gokul Nishanth
Courses Plus Student 581 Points

Bummer! Can't get the length of a `Hand`.

Now update Hand in hands.py. I'm going to use code similar to Hand.roll(2) and I want to get back an instance of Hand with two D20s rolled in it. I should then be able to call .total on the instance to get the total of the two dice.

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=0, die_class=D20, *args, **kwargs):
        if not die_class:
            raise ValueError("You must provide a die class")

        for _ in range(size):
            self.append(die_class())

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

2 Answers

Sai Yamanoor
Sai Yamanoor
4,301 Points
Sai Yamanoor
Sai Yamanoor
4,301 Points

Hands.roll needs to be a class method that creates an instance of Hand

Murat Mermerkaya
Murat Mermerkaya
2,346 Points
Murat Mermerkaya
Murat Mermerkaya
2,346 Points

Kenneth Love Gokul Nishanth Gokul Nishanth S Sai Yamanoor

What's wrong with this code?

""" python

from dice import D20

class Hand(list): def init(self, size = 2, die_class = D20 ): super.__init()

@classmethod
def roll(cls, size=0, die_class=D20, *args, **kwargs):
    if not die_class:
        raise ValueError("You must provide a die class")

    for _ in range(size):
        self.append(die_class())




@property
def total(self):
    return sum(self)"""
Ken LaRose
seal-mask
.a{fill-rule:evenodd;}techdegree
Ken LaRose
Python Web Development Techdegree Student 21,982 Points
Ken LaRose
.a{fill-rule:evenodd;}techdegree
Ken LaRose
Python Web Development Techdegree Student 21,982 Points

the @classmethod should return an instance of the class using "return cls(blah, blah, blah)". The arguments will depend on how you set up your init method. I imagine two ways of doing it: 1. just pass the size argument into init and let it take the rest from there (that's what I did). or, 2. assemble a list of D20s in the roll method and then pass them over to init to instantiate the Hand object. Either way should work (probably). Good luck - this challenge was driving me crazy for about 3 hours this afternoon!