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Python Object-Oriented Python Dice Roller RPG Roller

akiva grobman
akiva grobman
9,160 Points
Posted by akiva grobman
akiva grobman
9,160 Points

I'm not getting any specific error message only "Try again!".

I'm not getting any specific error message only "Try again!", I can't find the problem, any ideas? Thanks in advance.

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 __init__():
        super().__init__()

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

    @classmethod 
    def roll(cls, num_of_dice):
        h = Hand()
        for _ in len(num_of_dice):
            h.append(D20())
        retrun h

2 Answers

Brandon White
.a{fill-rule:evenodd;}techdegree seal-36
Brandon White
Full Stack JavaScript Techdegree Graduate 34,660 Points

Hi akiva,

I’m seeing too small errors, both of which are easy to skip over, so no fret.

The first is, in your for loop in hands.py you’re trying to get the len of a number when you should be using the range function here. So instead of len(num_of_dice) try range(num_of_dice).

That said you would have figured that out on your own if not for the other small error. You’ve spelled return incorrectly. So a hand object is not actually being returned from the roll class method right now. Fix those two things and you’ll be good to go.

akiva grobman
akiva grobman
9,160 Points
akiva grobman
akiva grobman
9,160 Points

Thank you very much, I have made those changes and I'm now getting a new error "Can't get the length of a Hand".

Brandon White
.a{fill-rule:evenodd;}techdegree seal-36
Brandon White
Full Stack JavaScript Techdegree Graduate 34,660 Points

Can you post a copy of your code? Based on the error it sounds like you’re attempting to pass a Hand object as an argument into the len function. So I’d need to see that to evaluate it.

That said, you don’t need to use the len function at all for either of the two challenges.

akiva grobman
akiva grobman
9,160 Points
akiva grobman
akiva grobman
9,160 Points

This is the code, I'm getting a "Can't get the length of a `Hand" message. Thanks.

from dice import D20

class Hand(list):

def __init__():
    super().__init__()

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

@classmethod 
def roll(cls, num_of_dice):
    h = Hand()
    for _ in range(num_of_dice):
        h.append(D20())
    return h
Brandon White
.a{fill-rule:evenodd;}techdegree seal-36
Brandon White
Full Stack JavaScript Techdegree Graduate 34,660 Points

OK akiva,

So the error is being caused by something in the superclass’s init method. It didn’t pop up for me originally because when I copy/pasted your code into the challenge the first thing I did was remove the init method you added (because it wasn’t a part of the instructions). I didn’t mention that to you because I didn’t think it would affect your code in any functional way (and I didn’t want to tell you to remove the init method simply because it wasn’t necessary to this particular challenge).

As it turns out though, the list class’s init method seems to be passing the instantiated Hand object into the len function, and there’s nothing that tells the python interpreter how to deal with that. So the program is crashing.

Remove the init method, or at least switch out: super().__init__() for pass. That should get you moving forward.