Raymond Hettinger added the comment: I don't want to recommend overwriting the variable name but will add a note for the rest: "Copied iterators depend the original iterator. If the original advances, then so do the copies. After teeing the iterators, the usual practice is to stop working with the original iterator and operate only on the new tee-ed iterators." FWIW, the situation is analogous to str.upper(). We note that string methods produce new strings. We don't state that a best practice is to overwrite the variable with "s = s.upper()". That is sometimes what you want and sometimes not. ---------- priority: normal -> low _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue19441> _______________________________________

Raymond Hettinger <raymond.hettinger@gmail.com> added the comment: This is out of date. The docs currently have: ''' Once :func:`tee` has made a split, the original *iterable* should not be used anywhere else; otherwise, the *iterable* could get advanced without the tee objects being informed. ''' ---------- resolution: -> out of date stage: -> resolved status: open -> closed _______________________________________ Python tracker <report@bugs.python.org> <https://bugs.python.org/issue19441> _______________________________________