1 ! Copyright (C) 2007, 2008 Slava Pestov.
2 ! See http://factorcode.org/license.txt for BSD license.
3 USING: math alien.accessors kernel kernel.private sequences
9 : n>byte -3 shift ; inline
11 : byte/bit ( n alien -- byte bit )
12 over n>byte alien-unsigned-1 swap 7 bitand ; inline
14 : set-bit ( ? byte bit -- byte )
15 2^ rot [ bitor ] [ bitnot bitand ] if ; inline
17 : bits>cells 31 + -5 shift ; inline
19 : (set-bits) ( bit-array n -- )
20 over length bits>cells -rot [
21 spin 4 * set-alien-unsigned-4
22 ] 2curry each ; inline
26 M: bit-array length array-capacity ;
28 M: bit-array nth-unsafe
29 >r >fixnum r> byte/bit bit? ;
31 M: bit-array set-nth-unsafe
33 [ byte/bit set-bit ] 2keep
34 swap n>byte set-alien-unsigned-1 ;
36 : clear-bits ( bit-array -- ) 0 (set-bits) ;
38 : set-bits ( bit-array -- ) -1 (set-bits) ;
40 M: bit-array clone (clone) ;
42 : >bit-array ( seq -- bit-array ) ?{ } clone-like ; inline
44 M: bit-array like drop dup bit-array? [ >bit-array ] unless ;
46 M: bit-array new-sequence drop <bit-array> ;
49 over bit-array? [ sequence= ] [ 2drop f ] if ;
54 : integer>bit-array ( int -- bit-array )
55 [ log2 1+ <bit-array> 0 ] keep
57 [ -8 shift ] [ 255 bitand ] bi
58 -roll [ [ set-alien-unsigned-1 ] 2keep 1+ ] dip
62 : bit-array>integer ( bit-array -- int )
63 dup >r length 7 + n>byte 0 r> [
64 swap alien-unsigned-1 swap 8 shift bitor
67 INSTANCE: bit-array sequence