factor/basis/persistent/hashtables/hashtables.factor

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1.5 KiB
Factor

! Based on Clojure's PersistentHashMap by Rich Hickey.
USING: accessors assocs combinators kernel make math
parser persistent.assocs persistent.hashtables.nodes
prettyprint.custom ;
IN: persistent.hashtables
TUPLE: persistent-hash
{ root read-only initial: empty-node }
{ count fixnum read-only } ;
M: persistent-hash assoc-size count>> ;
M: persistent-hash at*
[ dup hashcode >fixnum ] [ root>> ] bi* (entry-at)
dup [ value>> t ] [ f ] if ;
M: persistent-hash new-at
[
[ 0 ] 3dip
[ dup hashcode >fixnum ] [ root>> ] bi* (new-at) 1 0 ?
] [ count>> ] bi + persistent-hash boa ;
M: persistent-hash pluck-at
[ [ dup hashcode >fixnum ] [ root>> ] bi* (pluck-at) ] keep
{
{ [ 2dup root>> eq? ] [ nip ] }
{ [ over not ] [ 2drop T{ persistent-hash } ] }
[ count>> 1 - persistent-hash boa ]
} cond ;
M: persistent-hash >alist [ root>> >alist% ] { } make ;
M: persistent-hash keys >alist keys ;
M: persistent-hash values >alist values ;
: >persistent-hash ( assoc -- phash )
T{ persistent-hash } swap [ swap rot new-at ] assoc-each ;
M: persistent-hash equal?
over persistent-hash? [ assoc= ] [ 2drop f ] if ;
M: persistent-hash hashcode* nip assoc-size ;
M: persistent-hash clone ;
SYNTAX: PH{ \ } [ >persistent-hash ] parse-literal ;
M: persistent-hash pprint-delims drop \ PH{ \ } ;
M: persistent-hash >pprint-sequence >alist ;
M: persistent-hash pprint* pprint-object ;
: passociate ( value key -- phash )
T{ persistent-hash } new-at ; inline