"""http://ginstrom.com/scribbles/2007/10/08/design-patterns-python-style/""" """Implementation of the iterator pattern with a generator""" def count_to(count): """Counts by word numbers, up to a maximum of five""" numbers = ["one", "two", "three", "four", "five"] # enumerate() returns a tuple containing a count (from start which # defaults to 0) and the values obtained from iterating over sequence for pos, number in zip(range(count), numbers): yield number # Test the generator count_to_two = lambda: count_to(2) count_to_five = lambda: count_to(5) print('Counting to two...') for number in count_to_two(): print(number, end=' ') print() print('Counting to five...') for number in count_to_five(): print(number, end=' ') print()
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