(when (or pos (not buffer))
;; If newline is at index I, and pointer at index I+N, charpos
;; is N-1. If there is no newline, and pointer is at index N,
(when (or pos (not buffer))
;; If newline is at index I, and pointer at index I+N, charpos
;; is N-1. If there is no newline, and pointer is at index N,