On Thu, Aug 6, 2015 at 1:25 AM, John Doe <z2...@bk.ru> wrote: > To pass by reference or by copy of - that is the question from hamlet. > ("hamlet" - a community of people smaller than a village python3.4-linux64) > > xlist = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] > i = 0 > for x in xlist: > print(xlist) > print("\txlist[%d] = %d" % (i, x)) > if x%2 == 0 : > xlist.remove(x) > print(xlist, "\n\n") > i = i + 1 > > So, catch the output and help me, PLEASE, improve the answer: > Does it appropriate ALWAYS REevaluate the terms of the expression list in > FOR-scope on each iteration? > But if I want to pass ONCE a copy to FOR instead of a reference (as seen > from an output) and reduce unreasonable reevaluation, what I must to do for > that?
This list is for the development *of* Python, rather than development *with* Python. If you repost your question to python-l...@python.org (the main user list), I'll be happy to explain over there what's going on and how to sort this out! But the simple answer is: Don't mutate the thing you're iterating over. You can take a copy with xlist[:] and iterate over that, if you like. ChrisA _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com