deferred class
	EV_CONTAINABLE

General
	cluster: vision2.interface.properties
	description: "Abstraction for objects that may be parented."
	keywords: "parentable, containable, child"

Ancestors
	EV_ANY

Queries
	data: ANY
	is_destroyed: BOOLEAN
	parent: EV_ANY

Commands
	copy (other: [like Current] EV_CONTAINABLE)
	destroy
	set_data (some_data: [like data] ANY)