language agnostic - What are some useful or interesting infinite generators? -

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what clever uses infinite generators? i've seen lots of seemingly trivial examples "list numbers", assume there must others have more applicability real-world scenarios. concrete examples (in language support generators) appreciated!

i'll give trivial sample answer.

look @ haskell code on http://rosettacode.org/wiki/hamming_numbers#haskell; uses lazy lists (which generators) in creative way list hamming numbers.


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