Normally I wouldn't link to meta discussion but this was such a weird borderline case that I spent over an hour trying to figure it out. Maybe that makes it interesting.
Edit: in case anyone's confused about the sequence here, micahflee posted the current thread 2 days ago. The timestamp at the top of this page is an artifact of us re-upping it (https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que...).