16 lines
447 B
Factor
16 lines
447 B
Factor
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! Copyright (C) 2008 Doug Coleman.
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! See http://factorcode.org/license.txt for BSD license.
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USING: checksums classes.singleton kernel math math.ranges
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math.vectors sequences ;
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IN: checksums.adler-32
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SINGLETON: adler-32
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: adler-32-modulus 65521 ; inline
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M: adler-32 checksum-bytes ( bytes checksum -- value )
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drop
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[ sum 1+ ]
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[ [ dup length [1,b] <reversed> v. ] [ length ] bi + ] bi
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[ adler-32-modulus mod ] bi@ 16 shift bitor ;
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