RetroSearch Browse

Wed Aug 5 17:53:58 CEST 2015 · https://mail.python.org/pipermail/python-dev/2015-August/141111.html

The iterator is not revaluated, instead, it is constructing a single
iterator, in this case a list_iterator. The list_iterator looks at the
underyling list to know how to iterate so when you mutate the underlying
list, the list_iterator sees that. This does not mee the expression used to
generate the iterator was re-evaluated.

On Wed, Aug 5, 2015 at 11:25 AM, John Doe <z2911 at 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?
> _______________________________________________
> Python-Dev mailing list
> Python-Dev at python.org
> https://mail.python.org/mailman/listinfo/python-dev
> Unsubscribe:
> https://mail.python.org/mailman/options/python-dev/joe%40quantopian.com
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-dev/attachments/20150805/27bde02b/attachment.html>

Home - News ( United States | United Kingdom | Italy | Germany ) - Football scores

Showing content from https://mail.python.org/pipermail/python-dev/2015-August/141111.html below:

[Python-Dev] who must makes FOR loop quicker