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20 lines
561 B
Plaintext
20 lines
561 B
Plaintext
# Declare a function that behaves like an iterator.
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# Any function with yield returns generator.
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# Generators follow lazy evaluation.
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# lazy evaluation means that the object is evaluated when it is needed,
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# not when it is created.
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def my_generator(start, end, step=1):
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while start < end:
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yield start
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start += step
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gen = my_generator(start=1, end=10)
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next(gen), next(gen), next(gen)
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# (1, 2, 3)
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gen = (i for i in range(1, 100) if i%2==0)
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next(gen), next(gen), next(gen), next(gen)
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# (2, 4, 6, 8)
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# https://wiki.python.org/moin/Generators |