44 lines
1001 B
Factor
44 lines
1001 B
Factor
! Copyright (C) 2003, 2007 Slava Pestov.
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! See http://factorcode.org/license.txt for BSD license.
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USING: kernel math sequences ;
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IN: io.binary
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: le> ( seq -- x ) 0 [ 8 * shift + ] reduce-index ;
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: be> ( seq -- x ) 0 [ [ 8 shift ] dip + ] reduce ;
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: mask-byte ( x -- y ) 0xff bitand ; inline
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: nth-byte ( x n -- b ) -8 * shift mask-byte ; inline
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<PRIVATE
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: map-bytes ( x seq -- byte-array )
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[ nth-byte ] with B{ } map-as ; inline
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PRIVATE>
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: >le ( x n -- byte-array ) iota map-bytes ;
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: >be ( x n -- byte-array ) iota <reversed> map-bytes ;
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: d>w/w ( d -- w1 w2 )
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[ 0xffffffff bitand ] [ -32 shift 0xffffffff bitand ] bi ;
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: w>h/h ( w -- h1 h2 )
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[ 0xffff bitand ] [ -16 shift 0xffff bitand ] bi ;
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: h>b/b ( h -- b1 b2 )
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[ mask-byte ] [ -8 shift mask-byte ] bi ;
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<PRIVATE
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: signed> ( x seq -- n )
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length 8 * 2dup 1 - bit? [ 2^ - ] [ drop ] if ; inline
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PRIVATE>
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: signed-le> ( bytes -- x ) [ le> ] [ signed> ] bi ;
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: signed-be> ( bytes -- x ) [ be> ] [ signed> ] bi ;
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