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Python

Ian McGlory
Ian McGlory
1,997 Points

draw_map()

I've been scratching my head trying to get draw map to work. All I get back is an error:

UnboundLocalError: local variable 'output' referenced before assignment.

Below is some of my code which for the sake of the question I've only replicated the necessary bits.

import random

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),
        ]

def get_locations():
    return random.sample(CELLS, 3)

monster,door,player = get_locations()
def draw_map(player):
    print(" _"*5)
    tile = "|{}"
    for cell in CELLS:
        x, y = cell
        if x<4:
            line_end = ""
            if cell == player:
                output = tile.format("X")
            else: 
                tile.format("_")
        else:
            line_end = "\n"
            if cell == player:
                output = tile.format("X|")
            else: 
                output = tile.format("_|")
        print(output, end = line_end)        


draw_map(player)

From what I know, the code is telling me that output is being referenced before it's being assigned to a value. However, this is just about verbatim from what I saw in the video. What am I doing wrong?

1 Answer

You need to assign output before using it in your for loop.

def draw_map(player):
    output = ""

Assign it within the function, before the for-loop.