On Wed, Aug 24, 2016, at 07:17, Chris Angelico wrote: > Objects/listobject.c:795 > > /* Special cases: > 1) lists and tuples which can use PySequence_Fast ops > 2) extending self to self requires making a copy first > */
And, of course, it is a special case - a.extend(iter(a)) is enough to break it. Frankly I'm not sure why bother to implement it when anyone who legitimately wants to do it can simply do a *= 2. -- https://mail.python.org/mailman/listinfo/python-list
