Hi everyone,

After reading the answer to this question, I learned that SFINAE can be used to choose between two functions based on whether the class has a certain member function. It's the equivalent of the following, just that each branch in the if statement is split into an overloaded function:

template<typename T>
void Func(T& arg)
{
    if(HAS_MEMBER_FUNCTION_X(T))
        arg.X();
    else
        //Do something else because T doesn't have X()
}

becomes

template<typename T>
void Func(T &arg, int_to_type<true>); //T has X()

template<typename T>
void Func(T &arg, int_to_type<false>); //T does not have X()

I was wondering if it was possible to extend SFINAE to do multiple rules. Something that would be the equivalent of this:

template<typename T>
void Func(T& arg)
{
    if(HAS_MEMBER_FUNCTION_X(T))                //See if T has a member function X  
        arg.X();
    else if(POINTER_DERIVED_FROM_CLASS_A(T))    //See if T is a pointer to a class derived from class A
        arg->A_Function();              
    else if(DERIVED_FROM_CLASS_B(T))            //See if T derives from class B
        arg.B_Function();
    else if(IS_TEMPLATE_CLASS_C(T))             //See if T is class C<U> where U could be anything
        arg.C_Function();
    else if(IS_POD(T))                          //See if T is a POD type
        //Do something with a POD type
    else
        //Do something else because none of the above rules apply
}

Is something like this possible?

Thank you.