39 lines
1.0 KiB
Factor
39 lines
1.0 KiB
Factor
|
USING: kernel sequences arrays math vectors ;
|
||
|
|
IN: hash2
|
||
|
|
|
||
|
|
! Little ad-hoc datastructure used to map two numbers
|
||
|
|
! to a single value.
|
||
|
|
! Created for the NFC mapping table.
|
||
|
|
! We could use a hashtable of 2arrays, but that
|
||
|
|
! involves creating too many objects.
|
||
|
|
! Does not allow duplicate keys.
|
||
|
|
|
||
|
|
: hashcode2 ( a b -- hashcode )
|
||
|
|
swap 8 shift + ; inline
|
||
|
|
|
||
|
|
: <hash2> ( size -- hash2 ) f <array> ;
|
||
|
|
|
||
|
|
: 2= ( a b pair -- ? )
|
||
|
|
first2 swapd >r >r = r> r> = and ; inline
|
||
|
|
|
||
|
|
: (assoc2) ( a b alist -- {a,b,val} )
|
||
|
|
[ >r 2dup r> 2= ] find >r 3drop r> ; inline
|
||
|
|
|
||
|
|
: assoc2 ( a b alist -- value )
|
||
|
|
(assoc2) dup [ third ] when ; inline
|
||
|
|
|
||
|
|
: set-assoc2 ( value a b alist -- alist )
|
||
|
|
>r rot 3array r> ?push ; inline
|
||
|
|
|
||
|
|
: hash2@ ( a b hash2 -- a b bucket hash2 )
|
||
|
|
>r 2dup hashcode2 r> [ length mod ] keep ; inline
|
||
|
|
|
||
|
|
: hash2 ( a b hash2 -- value/f )
|
||
|
|
hash2@ nth [ assoc2 ] [ 2drop f ] if* ;
|
||
|
|
|
||
|
|
: set-hash2 ( a b value hash2 -- )
|
||
|
|
>r -rot r> hash2@ [ set-assoc2 ] change-nth ;
|
||
|
|
|
||
|
|
: alist>hash2 ( alist size -- hash2 )
|
||
|
|
<hash2> [ over >r first3 r> set-hash2 ] reduce ; inline
|