Question

Could anyone tell me why this doesn’t work?

enum CompCriteria{ByKey,ByValue,ByeKeyAndValue};

template<class T>
struct X;

template<>
struct X<CompCriteria>
{
};

int _tmain(int argc, _TCHAR* argv[])
{
    X<CompCriteria::ByeKeyAndValue> x;
    return 0;
}

Answer 1

You have specialized X for a type, but you’re trying to use it with the integer CompCriteria::ByeKeyAndValue.

You can specialize template class for the enum CompCriteria underlying type – int in this case, as follows:

enum CompCriteria{ByKey,ByValue,ByeKeyAndValue};

template<int>
struct X;

template<>
struct X<ByeKeyAndValue>
{
};

int main()
{
    X<ByeKeyAndValue> x;
    return 0;
}