20 lines
559 B
Python
20 lines
559 B
Python
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import itertools
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def iter_primes():
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# an iterator of all numbers between 2 and +infinity
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numbers = itertools.count(2)
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# generate primes forever
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while True:
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# get the first number from the iterator (always a prime)
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prime = numbers.next()
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yield prime
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# this code iteratively builds up a chain of
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# filters...slightly tricky, but ponder it a bit
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numbers = itertools.ifilter(prime.__rmod__, numbers)
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for p in iter_primes():
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if p > 1000:
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break
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print p
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