def nav(options = {}, &block)
      nav = Bh::Nav.new(self, options, &block)
      nav.extract! :as, :layout

      nav.append_class! :nav
      if Bh::Stack.find(Bh::Navbar)
        nav.append_class! :'navbar-nav'
      else
        nav.merge! role: :tablist
        nav.append_class! nav.style_class
        nav.append_class! nav.layout_class
      end

      nav.render_tag :ul
    end
def nav(options = {}, &block)
      nav = Bh::Nav.new(self, options, &block)
      nav.extract! :as, :layout

      nav.append_class! :nav
      if Bh::Stack.find(Bh::Navbar)
        nav.append_class! :'navbar-nav'
      else
        nav.merge! role: :tablist
        nav.append_class! nav.style_class
        nav.append_class! nav.layout_class
      end

      nav.render_tag :ul
    end
Displays a Bootstrap-styled nav.
 @see http://getbootstrap.com/components/#nav
 @return [String] the HTML to display a Bootstrap-styled nav.
 @param [Hash] options the options for the nav. Any option not listed below
   is passed as an HTML attribute to the alert’s `<ul>`.
 @option options [#to_s] :as (:tabs) the style of the nav. Can be `:tabs`
   or `:pills`.
 @option options [#to_s] :layout the layout of the nav. Can be
   `:justified` or `:stacked`.
 @yieldreturn [#to_s] the content to display in the nav.
 @example Display a pills-styled nav with a link.
   nav as: :pills do
     link_to 'Home', '/'
   end