# File lib/rvg/clippath.rb, line 25
            def initialize(clip_path_units='userSpaceOnUse')
                super()
                if ! ['userSpaceOnUse', 'objectBoundingBox'].include?(clip_path_units)
                    raise ArgumentError, "undefined value for clip path units: #{clip_path_units}"
                end
                @clip_path_units = clip_path_units
                @content = Content.new
                yield(self) if block_given?
            end