C++标准typeof关键字应用

#include <iostream>

class Test1
{
public:
    static void getuid()
    {
        std::cout << "has getuid func!" << std::endl;
    }
};

class Test2
{
};

template<typename T, bool b>
struct TBaseImpl
{
};

template<typename T>
struct TBaseImpl<T, true>
{
    static void getuid()
    {
        T::getuid();
    }
};

template<typename T>
struct TBaseImpl<T, false>
{
    static void getuid()
    {
        std::cout << "not found getuid!" << std::endl;
    }
};

template<typename T>
class has_getuid
{
public:
    template<typename C>
    static char test(typeof(&C::geuid));

    template<typename C>
    static long test(...);

    enum { value = sizeof(test<T>(0)) == sizeof(char) };
};

int main()
{
    TBaseImpl<Test2, has_getuid<Test2>::value>::getuid();
    TBaseImpl<Test1, has_getuid<Test1>::value>::getuid();
    return 0;
}