模板函数指针成员函数

Question

大家新年快乐等

我有模板一些函数指针的麻烦：

到目前为止的代码如下：

template<class T> 
    class EventMapper 
    { 
    private: 
     typedef std::wstring const (T::*messageHandler)(std::wstring const & myMessage);    //!< Templated function pointer 
     typedef std::tr1::unordered_map<std::wstring, messageHandler> umap;        //!< abbreviation for eventHandler map container 
     typedef umap::const_iterator eventCIt;               //!< abbreviation for event map const_iterator 
     typedef umap::iterator eventIt;                //!< abbreviation for event map iterator 

     //test func ptr 
     T const & myInstance; 
     umap myEventMap; 
     eventCIt myCurrentCommand;                  //!< current selected command 
    public: 
     EventMapper(T const & instance_in) : myInstance(instance_in){} 

     //register an event handler 
     void registerHandler(std::wstring const & cmd_in, messageHandler handler_in) 
     { 
      this->myEventMap.insert(umap::value_type(cmd_in, handler_in)); 
     } 

MSVS 2008 SP1下我得到这个错误：

Error 3 error C2146: syntax error : missing ';' before identifier 'eventCIt' o:\AX_FusRecAlg\include\Reconstruction\JobListEditor\Types.h 19 AX.Services.Reconstruction.JobListDataProviderTest 

不是很具描述性。我正在努力做甚么？任何提示将受到欢迎！谢谢。

Answer 1

要解决你的代码，使用typename：

 typedef typename umap::const_iterator eventCIt;               //!< abbreviation for event map const_iterator 
     typedef typename umap::iterator eventIt; 

欲了解更多信息，看看template dependent names