         ->
           restoring_context fn, arguments
 
+      add_renderable: (renderable) ->
+        run_context.current_context.renderables.push renderable
+
+      output: (output) ->
+        $item = $ '<div class="item"/>'
+        if output?
+          $item.append output
+        run_context.add_renderable _lead_render: -> $item
+        $item
+
       render: (o) ->
         @nested 'renderable', handle_renderable, o
         # TODO warn if not renderable

      `with (context_scope) {`
      result = (-> eval string).call run_context
      `}`
      run_context.display_object result
    catch e
      run_context.handle_exception e, string

        @nested_item $item, fn, args...

      nested_item: ($item, fn, args...) ->
        nested_renderables = []
        run_context.add_renderable _lead_render: ->
          children = _.map nested_renderables, (i) -> i._lead_render()
          $item.append children
          $item

        nested_context = _.extend {}, run_context,
          renderables: nested_renderables
        run_context.in_context nested_context, fn, args

      handle_exception: (e, compiled) ->
