Vocabulary
persistent.hashtables.nodes

Definition


Methods

M:: bitmap-node (entry-at)
( key hashcode bitmap-node -- entry )
bitmap-node shift>> :> shift hashcode shift bitpos
:> bit bitmap-node bitmap>> :> bitmap bitmap-node nodes>>
:> nodes bitmap bit bitand 0 eq?
[ f ] [
key hashcode bit bitmap index nodes nth-unsafe
(entry-at)
] if ;



M:: bitmap-node (new-at)
( shift value key hashcode bitmap-node -- node' added-leaf )
bitmap-node shift>> :> shift hashcode shift bitpos
:> bit bitmap-node bitmap>> :> bitmap bit bitmap index
:> idx bitmap-node nodes>> :> nodes bitmap bit bitand 0 eq?
[
value key hashcode <leaf-node>
:> new-leaf bitmap bit bitor
new-leaf idx nodes insert-nth shift <bitmap-node>
new-leaf
] [
idx nodes nth :> n shift radix-bits +
value key hashcode n (new-at)
:> ( n' new-leaf ) n n' eq?
[ bitmap-node ]
[ bitmap n' idx nodes new-nth shift <bitmap-node> ] if
new-leaf
] if ;



M:: bitmap-node (pluck-at)
( key hashcode bitmap-node -- node' )
hashcode bitmap-node shift>> bitpos
:> bit bitmap-node bitmap>> :> bitmap bitmap-node nodes>>
:> nodes bitmap-node shift>> :> shift bit bitmap bitand
0 eq?
[ bitmap-node ] [
bit bitmap index :> idx idx nodes nth-unsafe
:> n key hashcode n (pluck-at) :> n' n n' eq?
[ bitmap-node ] [
n'
[ bitmap n' idx nodes new-nth shift <bitmap-node> ]
[
bitmap bit eq?
[ f ] [
bitmap bit bitnot bitand
idx nodes remove-nth shift <bitmap-node>
] if
] if
] if
] if ;