Question

以下是我项目的代码段：

template<typename Second, typename First = const UINT64>
class Event : virtual public id_manager<>
{
    friend class EventHandler;
    typedef std::map<First, EventHandler> eventMap;
    static eventMap mapper;
    static eventMap StartMapping()
    {
        eventMap temp;
        return temp;
    }
public:
    Event(){}
    void operator+=(EventHandler _handler)
    {
        mapper[this->getID()] = _handler;
    }
};
// INITIALIZATION FAILED HERE:
template<typename Second, typename First = const UINT64>
Event<Second, First>::eventMap Event<Second, First>::mapper(Event<Second, First>::StartMapping());

以下是Visual Studio 2010的输出错误：

警告1警告C4346：'Event :: eventMap'：依赖 name不是类型c：\ users \ admin \ documents \ visual studio 2010 \ projects \ cppsystem \ cppsystem \ main.cpp 67错误2错误C2143：语法错误：缺少';'之前 'event :: mapper'c：\ users \ admin \ documents \ visual studio 2010 \ projects \ cppsystem \ cppsystem \ main.cpp 67错误3错误C4430：缺少类型说明符 - 假设为int。注意：C ++不支持 default-int c：\ users \ admin \ documents \ visual studio 2010 \ projects \ cppsystem \ cppsystem \ main.cpp 67错误4错误C1903：无法从之前的错误中恢复;停止编译c：\ users \ admin \ documents \ visual studio 2010 \ projects \ cppsystem \ cppsystem \ main.cpp 67

我希望这段代码足够了。我无法使用该地图的“初始化功能”初始化静态地图成员。非常感谢！

Answer 1

您需要typename告诉编译器eventMap是一种类型。

template<typename Second, typename First = const UINT64>
typename Event<Second, First>::eventMap Event<Second, First>::mapper(Event<Second, First>::StartMapping());

请参阅The "typename" keyword

在模板化类中初始化static std :: map成员？

1 个答案: