16 lines
468 B
Factor
16 lines
468 B
Factor
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! Rewritten by Matthew Willis, July 2006
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! Copyright (C) 2004 Chris Double.
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! See http://factorcode.org/license.txt for BSD license.
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USING: lazy-lists math kernel sequences quotations ;
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IN: lazy-lists.examples
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: naturals 0 lfrom ;
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: positives 1 lfrom ;
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: evens 0 [ 2 + ] lfrom-by ;
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: odds 1 lfrom [ 2 mod 1 = ] lsubset ;
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: powers-of-2 1 [ 2 * ] lfrom-by ;
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: ones 1 [ ] lfrom-by ;
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: squares naturals [ dup * ] lmap ;
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: first-five-squares 5 squares ltake list>array ;
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