def to_s
			return @normalized if @normalized

			doctype = nil
			if @element
				doc = @element.document
				doctype = doc.doctype if doc
			end

			@normalized = Text::normalize( @unnormalized, doctype )
			@unnormalized = nil
      @normalized
		end
def to_s
			return @normalized if @normalized

			doctype = nil
			if @element
				doc = @element.document
				doctype = doc.doctype if doc
			end

			@normalized = Text::normalize( @unnormalized, doctype )
			@unnormalized = nil
      @normalized
		end
Returns the attribute value, with entities replaced