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,當我試圖按照以下步驟創建一個模板類:類模板+函數模板
template <typename TList>
class Variant
{
public :
std::string toString(); // var.toString()
template<typename T>
std::string toString(); // var.toStrint<int>();
protected:
template <typename T>
std::string toString(T v); // internal Specialization
template <>
std::string toString(int v); // internal Specialization
template <typename T>
const T & get()
{
std::size_t type_index = TypeListNamespace::IndexOf<TList, T>::value ;
if (type_index == max_num_of_t || type_index != _type_index)
throw std::bad_cast() ;
void * ptr = (void*) &_variant_holder;
T * vptr = reinterpret_cast<T *>(ptr);
return *vptr;
}
};
// CPP FILE:
template <typename TList>
std::string Variant<TList>::toString()
{
// var.toString()
}
template<typename TList>
template<typename T>
std::string Variant<TList>::toString()
{
return toString(get<T>());
}
template<typename TList>
template<typename T>
std::string Variant<TList>::toString (T v)
{
// no default toString method.
return "";
}
template<typename TList>
template<>
std::string Variant<TList>::toString (int v)
{
// Specialized toString for int values:
return Core::Utility::formatString("%i", v);
}
.. other specializations ..
我得到了以下錯誤:
error C2244: 'Core::Variant<TList>::toString': unable to match function definition to an existing declaration
2> Definition
2> 'std::string Core::Variant<TList>::toString(int)'
2> Available Deklarations
2> 'std::string Core::Variant<TList>::toString(T)'
2> 'std::string Core::Variant<TList>::toString(void)'
2> 'std::string Core::Variant<TList>::toString(void)'
當我有類定義這兩個特所有編譯馬上。所以我想我對模板語法做了錯誤。但是很難找到具有專業化的類和功能模板組合的例子。所以我最終在這裏希望有一個對我有好的暗示的人。