Variadic Mixin/Template classes?

[Chirs Forest via Digitalmars-d-learn]

I'd like to make a class that takes multiple template types (1 - 
several) which can hold an array/tuple of a second class that are 
instantiated with those types.

class Bar(T) {
    T bar;
}
class Foo(T[]){ // not sure how to take variadic types here?
    Bar!(?)[] bars; //not sure how I'd define an array/tuple of 
multiple types

    this(){
        foreach(int i, b; bars) b = new Bar!T[i];
    }
}

void main(){
    auto foo = new Foo!(string, int, string, ubyte[2]);

    foo.bars[0].bar = "hello";
    foo.bars[1].bar = 23;
    foo.bars[2].bar = "hello";
    foo.bars[3].bar[0] = 88;
    foo.bars[3].bar[1] = 99;

    auto foo2 = new Foo!(ubyte, string);
    foo.bars[0].bar = 9;
    foo.bars[1].bar = "world";
}