Can I overload functions with type-traits?

Question

Let\'s say, I have six types, and they each belong in a conceptual category.
Here is a diagram that shows this:

Answer 1

Two functions signatures are not allowed to differ only by the default value of a template parameter. What would happen if you explicitly called function< int, void >?

Usual usage of enable_if is as the function return type.

//Handle all types from Category 1
template
typename std::enable_if::value>::type
function(T t){
    //do category 1 stuff to the type
    return;
}

//Handle all types from Category 2
template
typename std::enable_if::value>::type
function(T t){
    //do category 2 stuff to the type
    return;
}