def url
      @url ||= if @collection.nil?
                 relative_path
               else
                 ::Bunto::URL.new({
                   :template     => @collection.url_template,
                   :placeholders => placeholders,
                 })
               end.to_s.gsub(%r!/$!, "")
    end
def url
      @url ||= if @collection.nil?
                 relative_path
               else
                 ::Bunto::URL.new({
                   :template     => @collection.url_template,
                   :placeholders => placeholders,
                 })
               end.to_s.gsub(%r!/$!, "")
    end
Applies a similar URL-building technique as Bunto::Document that takes
 the collection's URL template into account. The default URL template can
 be overriden in the collection's configuration in _config.yml.