Drawing a visual map of the dungeon game

Question

How does python know to print the dungeon map with three rows of three. Why would't things be printed on one line?
Here is the code, how does this result in a grid of 3x3
def draw_map(player):
  print(' _ _ _ ')
  tile = '|{}'
  for idx, cell in enumerate(CELLS):
    if idx in [0,1,3,4,6,7]:
      if cell == player:
        print(tile.format('X'), end='')
      else:
        print(tile.format(''), end='')
    else:
      if cell == player:
        print(tile.format('X|'))
      else:
        print(tile.format('|'))

Chris Bellmaine · Answer

Hi
Good question and trying to think how to explain
The main reason it prints the way it does is the end key that you put in to print. Normally python would print and then move to the next line and print the next thing and then the next line and so forth.. If python reads through the code and comes across end, it will set up to then print next to what was just printed, run the next part of the code and add it in that spot.
The reason this does only three in a line then goes to the next line is due to the idx set up. enumerate will create a count 0 1 2 3 etc.. So if idx in [0,1,3,4,6,7] means the first two times this loop is run 0 and 1 will come up and it will run code which has an end key in it which will continue to add the next printed item on the same line. After this though it will find 2. This starts your else code which doesn't have the end key so will stop printing on this line and move to the next. End result is your first line is 0,1,2 no more end key so breaks to the next line 3,4,5 again 5 is not in the list so moves to else and again no end key so third line is 6,7,8
If i recall the enumerate(cells) for this game would create 
python
(0, (0, 0)) 
(1, (0, 1)) 
(2, (0, 2)) #end of first line because the idx == 2 
(3, (1, 0)) etc

So the first run on your for loop pulls is idx == 0 and cell == (0, 0)
Hope this helps a little bit to understand the breakdown >_

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Connor Crawford

Connor Crawford

Drawing a visual map of the dungeon game

1 Answer

Chris Bellmaine

Chris Bellmaine