def new
  @comment = Comment.new
  
  respond_to do |format|
    format.js do
      render :update do |page|
        page.hide "add_comment_link_for_post_#{@post.id}"
        page.replace_html "new_comment_form_for_post_#{@post.id}",
                          :partial => "new"
      end
    end
  end
end

