unqualified types in tuple

[Dan]

If I have a type tuple TL, which happens to be:
  alias TypeTuple!(const(int), immutable(double), string) TL;
How can I convert it into a tuple of (int, double, string)?

Effectively I need a way to get a new UnqualTL where each type in 
the list is itself unqualified. I need to do this without knowing 
the alias.

Thanks
Dan