Hah, yes, I made that change mid-way through to allow for Ruby’s feature where you can mutate the default value of a Hash (a feature I personally have never use

Hah, yes, I made that change mid-way through to allow for Ruby’s feature where you can mutate the default value of a Hash (a feature I personally have never used), but didn’t update the text. Fix on the way. Thanks for spotting the discrepancy!