Casting between tuples

[Sean Eskapp]

I have a variable of type TypeTuple!(int, int), and I want to convert all its
elements into a variable of type TypeTuple!(string, string). Is there a way to
do this? Using a loop fails compilation with "Error: Integer constant
expression expected instead of i".

I'd also like to be able to convert from arrays of base classes (static size)
to TypeTuples of derived classes. "static for" doesn't work either. Is there a
way to do this.. without a recursive template function?