class HTML::Tag

def childless?(xml = false)

Returns non-+nil+ if this tag can contain child nodes.
def childless?(xml = false)
  return false if xml && @closing.nil?
  !@closing.nil? ||
    @name =~ /^(img|br|hr|link|meta|area|base|basefont|
                col|frame|input|isindex|param)$/ox
end