I think you don't really want to use length. Since it is a program evaluating last it might not be that bad as you have to goto the last element anyway. Here i

I think you don't really want to use length. Since it is a program evaluating last it might not be that bad as you have to goto the last element anyway. Here is mine: (defun our-last (list) (if (rest list) (our-last (rest list)) list))