    deferred class
    	EV_REGION_I

    General
    	cluster: implementation_mswin
    	description: "Implementation Interface for EV_REGION"

    Ancestors
    	EV_ANY_I*

    Queries
    	exclusive_or (a_region: EV_REGION): EV_REGION
    	intersect (a_region: EV_REGION): EV_REGION
    	is_region_equal (other: EV_REGION): BOOLEAN
    	subtract (a_region: EV_REGION): EV_REGION
    	union (a_region: EV_REGION): EV_REGION

    Commands
    	copy_region (other: EV_REGION)
    	offset (a_horizontal_offset, a_vertical_offset: INTEGER_32)
    	set_rectangle (a_rectangle: EV_RECTANGLE)