Yeah I immediately checked that after commenting since it's exactly the off-by-half thing I never get right without checking and yup, you can end up with a neve

Yeah I immediately checked that after commenting since it's exactly the off-by-half thing I never get right without checking and yup, you can end up with a never used code path. What a rollercoaster. Ah well. For this particular thing you do in fact end up with one. In other cases whenever I end up with an unfollowed code path I can usually refactor it out. Non-empty lists are a good way of doing that, for instance.