9.5: Printing the Deck
- Page ID
- 15471
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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 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.