link_to (ActionView::Helpers::UrlHelper)

    # File lib/action_view/helpers/url_helper.rb, line 218
          def link_to(*args, &block)
            if block_given?
              options      = args.first || {}
              html_options = args.second
              concat(link_to(capture(&block), options, html_options))
            else
              name         = args.first
              options      = args.second || {}
              html_options = args.third

              url = url_for(options)

              if html_options
                html_options = html_options.stringify_keys
                href = html_options['href']
                convert_options_to_javascript!(html_options, url)
                tag_options = tag_options(html_options)
              else
                tag_options = nil
              end

              href_attr = "href=\"#{url}\"" unless href
              "<a #{href_attr}#{tag_options}>#{name || url}</a>"
            end
          end