    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)