Moritz, why should a position depending use-case be passed around??? Do you pass around the head of foreach or the flip-flop-operator?

Sorry your completely missing the point, to find a solution for a one-way and one-place iterator+generator.

Evidently if the iterator has to be passed around, you definetely need a initial construction in a generator. CPAN has this already.

If you can't imagine, better think of literals:
nobody initializes a variable and use it just once in the next line, when he can just use a literal string...

TIMTOWTDI