class ActionView::CollectionRenderer

def render_collection_with_partial(collection, partial, context, block)
  iter_vars  = retrieve_variable(partial)
  collection = if collection.respond_to?(:preload_associations)
    PreloadCollectionIterator.new(collection, partial, iter_vars, collection)
  else
    SameCollectionIterator.new(collection, partial, iter_vars)
  end
  template = find_template(partial, @locals.keys + iter_vars)
  layout = if !block && (layout = @options[:layout])
    find_template(layout.to_s, @locals.keys + iter_vars)
  end
  render_collection(collection, context, partial, template, layout, block)
end