services.yml语法错误?Symfony

此YML文件中一定存在语法错误。因为例如，正如目前的情况一样，我得到了这个错误：

The function "appPendingTasks" does not exist in ::layout.html.twig at line 64 

但是，如果我删除twig.extension.show.responses块，它会正常工作！（除了当我加载需要show.responses的页面时，这显然不起作用）。

有人看到这个有什么不对吗？

# Learn more about services, parameters and containers at
# http://symfony.com/doc/current/book/service_container.html
parameters:
#    parameter_name: value
services:
    twig.extension.pending.tasks:
      class: MyApp'TaskBundle'Extensions'PendingTasksExtension
      arguments: [@doctrine.orm.entity_manager]
      tags:
        - { name: twig.extension }
    twig.extension.show.responses:
      class: MyApp'TaskBundle'Extensions'ShowResponsesExtension
      arguments: [@doctrine.orm.entity_manager]
      tags:
        - { name: twig.extension }
    twig.extension.show.question:
      class: MyApp'TaskBundle'Extensions'ShowQuestionExtension
      arguments: [@doctrine.orm.entity_manager]
      tags:
        - { name: twig.extension }