higher-node ( key tree -- node )

Vocabulary

trees.private

Inputs

key	an object
tree	an object

Outputs

node

an object

Definition

USING: accessors kernel math.order sequences ;

IN: trees.private

: higher-node ( key tree -- node )
    dupd nodepath-at
    [ drop f ] [
        reverse 2dup first higher-node-in-child?
        [ nip first right>> left-extremity ]
        [ [ key>> before? ] with find nip ] if
    ] if-empty ;