On Sat, Aug 7, 2021 at 5:22 AM Boris Dorestand <bdorest...@example.com> wrote: > > Jach Feng <jf...@ms4.hinet.net> writes: > > >> >>>>> s = "Jack Brandom" > >> >>>>> s[3 : -13 : -1] > >> >> 'kcaJ' > >> >> I have no idea how to replace that -13 with a positive index. Is it > >> >> possible at all? > > That's not possible because a positive index is relative to the leftmost > > item 0 > > And the middle index is always exclusive, so we can't go to the left of > 0 and remain positive. Okay, I think that answers it. It's not > possible at all. >
An absent index isn't the same as any specific positive value, so, yeah, it's not possible to replace it with a positive index. It IS possible to replace it with None. >>> s = "Jack Brandom" >>> s[3:None:-1] 'kcaJ' You could implement equivalent logic in your function. ChrisA -- https://mail.python.org/mailman/listinfo/python-list
