16 lines
574 B
Factor
16 lines
574 B
Factor
! 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: lists lists.lazy math kernel sequences quotations ;
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IN: lists.lazy.examples
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: naturals ( -- list ) 0 lfrom ;
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: positives ( -- list ) 1 lfrom ;
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: evens ( -- list ) 0 [ 2 + ] lfrom-by ;
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: odds ( -- list ) 1 lfrom [ 2 mod 1 = ] lfilter ;
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: powers-of-2 ( -- list ) 1 [ 2 * ] lfrom-by ;
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: ones ( -- list ) 1 [ ] lfrom-by ;
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: squares ( -- list ) naturals [ dup * ] lazy-map ;
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: first-five-squares ( -- list ) 5 squares ltake list>array ;
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