:- module rtree.
:- interface.
:- import_module list.
:- type box
	--->	box(float, float, float, float).
:- type box3d
	--->	box3d(float, float, float, float, float, float).
:- type interval
	--->	interval(float, float).
:- type rtree(K, V).
:- typeclass region(K).
:- instance (rtree.region(rtree.box)).
:- instance (rtree.region(rtree.box3d)).
:- instance (rtree.region(rtree.interval)).
