example.rb

  def insert_flash
    content_tag :div, class: 'flash' do 
      flash.each do |name, msg|
        add_flash name, msg
      end
    end
  end

private

  def add_flash(name, msg)
    return unless msg.is_a?(String)
    concat( content_tag( :div, class: "fade in alert alert-#{ flash_type_to_bootstrap(name) }")  do 
      # This would be a candidate for a method as well...
      concat( button_tag( "×".html_safe, class: "close", "aria-hidden" => true, "data-dismiss" => "alert" ) )
      concat( content_tag :div, msg, :id => "flash_#{name}" )
    end )
  end