# File lib/xtemplate/xml.rb, line 287
    def doctype(root, pub_sys, long_name, uri)
      if( root && pub_sys && uri )
        push_content("<!DOCTYPE #{root} #{pub_sys} \"#{long_name}\" \"#{uri}\">")
      elsif( root && pub_sys && !uri )
        push_content("<!DOCTYPE #{root} #{pub_sys} \"#{long_name}\">")
      elsif( root && !pubid && !uri )
        push_content("<!DOCTYPE #{root}>")
      end
      push_content(NEWLINE)
    end