def underline
         style           = CharacterStyle.new
         style.underline = true
         if block_given?
            apply(style) {|node| yield node}
         else
            apply(style)
         end
      end
def underline
         style           = CharacterStyle.new
         style.underline = true
         if block_given?
            apply(style) {|node| yield node}
         else
            apply(style)
         end
      end
This method provides a short cut means of creating an underline command
 node. The method accepts a block that will be passed a single parameter
 which will be a reference to the underline node created. After the block
 is complete the underline node is appended to the end of the child nodes
 on the object that the method is call against.