How to tell if class contains a certain member function in compile time [duplicate]

Answer 1

Stealing from here, and assuming you fix your code so GetInt is const, we get:

HAS_MEM_FUNC(GetInt, has_GetInt);

template 
struct bool_type
{
    static const bool value = B;
};

typedef bool_type true_type;
typedef bool_type false_type;

namespace detail
{
    template 
    int get_int(const T& pX, true_type)
    {
        return pX.GetInt();
    }

    template 
    int get_int(const T& pX, false_type)
    {
        return pX.m;
    }
}

template 
int get_int(const T& pX)
{
    return detail::get_int(pX,
                            has_GetInt::value);
}

This is pretty awful design though. You should fix the problem rather than apply a patch.