updated to match Listing 2.1

In the book you say (pg 41): Groovy automatically exposes an implicit variable named it to indicate the loop iteration index.

I'm going through your book now and would be more than happy to continue to contribute back any discrepancies that might exist; however, I could also see how this might be really annoying for you. Annoyance couldn't be further from my intention, as I'm incredibly grateful for time you've already put into this, so let me know if I should continue.