deferred class
	EV_MODEL_ARROWED

General
	cluster: interface
	description: "Figure that can have an arrowhead at its start or endpoint."
	keywords: "figure, line, arrow"

Ancestors
	ANY
	EV_MODEL_DOUBLE_MATH

Queries
	arrow_size: INTEGER_32
	is_end_arrow: BOOLEAN
	is_start_arrow: BOOLEAN
	line_width: INTEGER_32

Commands
	disable_end_arrow
	disable_start_arrow
	enable_end_arrow
	enable_start_arrow
	set_arrow_size (an_arrow_size: [like arrow_size] INTEGER_32)