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Python Python Collections (2016, retired 2019) Dungeon Game Win or Lose

Hai Phan
Hai Phan
2,442 Points
Posted by Hai Phan
Hai Phan
2,442 Points

I can't add new monsters, please help!

This is a part of my game that I'm testing out, I want to add a new monster after 3 moves, but I got this error "TypeError: object of type 'NoneType' has no len()". Anyone can help me, please!

import os
import random

SMALL_CELLS = [
(0,0),(1,0),(2,0),(3,0),(4,0),
(0,1),(1,1),(2,1),(3,1),(4,1),
(0,2),(1,2),(2,2),(3,2),(4,2),
(0,3),(1,3),(2,3),(3,3),(4,3),
(0,4),(1,4),(2,4),(3,4),(4,4)
]

ALL_MONSTERS = [(1,1), (2,2), (3,3)]
ALL_MOVES = ["A", "S", "D"]
custom_cells = SMALL_CELLS
player = random.choice(SMALL_CELLS)

def new_monster(custom_cells, player, ALL_MOVES, ALL_MONSTERS):
    if custom_cells == SMALL_CELLS:
        if len(ALL_MOVES) == 0:
            print("** New monster will appear in 3 moves **")
        elif len(ALL_MOVES) % 3 == 1:
            print("** New monster will appear in 2 moves **")
        elif len(ALL_MOVES) % 3 == 2:
            print("** New monster will appear in 1 moves **")
        elif len(ALL_MOVES) % 3 == 0:
            print("** New monster will appear in 3 moves **")
            abc = random.choice(custom_cells.copy().remove(player))
            ALL_MONSTERS.append(abc)
        return ALL_MONSTERS

print(new_monster(custom_cells, player, ALL_MOVES, ALL_MONSTERS))

1 Answer

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,971 Points

The remove method doesn't return anything so in your code custom_cells.copy().remove(player) = none. I made the following modification:

elif len(ALL_MOVES) % 3 == 0:
    print("** New monster will appear in 3 moves **")

    abc = custom_cells.copy()
    abc.remove(player)
    abc = random.choice(abc)     
    ALL_MONSTERS.append(abc)
return ALL_MONSTERS

Not sure what this does without seeing the rest of the code.

Hai Phan
Hai Phan
2,442 Points
Hai Phan
Hai Phan
2,442 Points

Thanks for the answer, this helps me a lot! :+1: