18.5: Printing the deck
- Page ID
- 40840
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Here is a __str__ method for Deck:
#inside class Deck:
def __str__(self):
res = []
for card in self.cards:
res.append(str(card))
return '\n'.join(res)
This method demonstrates an efficient way to accumulate a large string: building a list of strings and then using the string method join. The built-in function str invokes the __str__ method on each card and returns the string representation.
Since we invoke join on a newline character, the cards are separated by newlines. Here’s what the result looks like:
>>> deck = Deck() >>> print(deck) Ace of Clubs 2 of Clubs 3 of Clubs ... 10 of Spades Jack of Spades Queen of Spades King of Spades
Even though the result appears on 52 lines, it is one long string that contains newlines.