tree.sepro

# Self-organizing trees
#

CONCEPT node
    TAG free
    SLOT left, right

CONCEPT head
    TAG open, node
    SLOT left, right

WHERE node, open AND NOT BOUND left ON free, node DO
    BIND left TO other
    IN other UNSET free
    IN other SET open

WHERE node, open AND NOT BOUND right ON free, node DO
    BIND right TO other
    IN other UNSET free
    IN other SET open

WHERE node, open AND BOUND left AND BOUND right  DO
    UNSET open

WORLD main
    OBJECT head * 5
    OBJECT node * 1000