How do I pass a type as parameter in this method?

[Marc]

Imaginary code:

> int index = FirstOrDefault!(int)(__traits(getAttributes, C.a));

In that case, if the tuple is empty, the value is the int's type 
default value.

The method is defined as  following:

> template FirstOrDefault(X)(T...) {
> 	static if(T.length > 0) {
> 		enum FirstOrDefault = T[0];
> 	} else {
> 		enum FirstOrDefault = X.init;
> 	}
> }