Rails signatures ...

gistfile1.txt

      # Creates a Twitter Bootstrap nav item.
      #
      # @see http://twitter.github.com/bootstrap/components.html#navs
      #
      # @param [String optional] caption The caption of the item, optional if a block is passed
      # @param [String optional] url The URL of the item
      # @param [Hash] options
      # @option options [Boolean] :brand (false) Set to true to define this item as the brand (this should be called directly on the `navbar` element itself as it also omits the surrounding `li` element)
      # @option options [Boolean] :icon (nil) Pass the name of an icon (without the prefix `icon-`) to have an icon displayed to the left of the caption; see [available icons](http://twitter.github.com/bootstrap/base-css.html#icons)
      # @return [String] HTML code
      def item(*args, &block)
        options = args.extract_options!
        options.reverse_update({
          brand: false,
          icon: false,
        })
        
        caption, url = if block_given?
          [capture(&block), args[0]]
        else
          [args[0], args[1]]
        end

        a_classes = []
        a_classes << 'brand' if options[:brand]
        
        icon_content = (options[:icon] ? content_tag(:i, '&nbsp;'.html_safe, class: "icon-#{options[:icon]}") : '').html_safe

        content = link_to(url, class: a_classes.join(' ')) do
          icon_content + caption
        end
        
        options[:brand] ? content : content_tag(:li, content)
      end

Hi again (coming from http://stackoverflow.com/questions/12423224/how-to-merge-some-keys-into-args-and-then-call-another-method-with-those-args/12423413#12423413)

Of, that's what Rails does so I guess is a valid approach (though personally I don't like it). An alternative is using two different methods if it's to be used with a block. Yeah, not a wonderful alternative, but more cleaner on the signatures side (and the code will be cleaner, less conditionals).

Minor suggestion on the functional side:

a_classes = ['brand' if options[:brand]].compact

I thought comments were editable... well, anyway, I meant:

a_classes = [('brand' if options[:brand])].compact