Iterator, modify data in loop body
Chris Angelico
rosuav at gmail.com
Sat Sep 13 03:22:54 EDT 2014
On Sat, Sep 13, 2014 at 5:01 PM, Michael Welle <mwe012008 at gmx.net> wrote:
> ideed, this works for the minimal example. In a real application list
> comprehension might be a bit unhandy, because there is a lot of code
> involved.
Sure. Sometimes, cutting something down for posting makes a completely
different solution possible, and that doesn't much help. :)
> It depends on the use case I think. For some algorithms it feels natural
> to just append at the end of the list while consuming elements from the
> front. I think a deque supports that as well.
In that case, don't iterate over the list at all. Do something like this:
while lst:
element = lst.pop(0)
# work with element
lst.append(new_element)
There's no mutation-while-iterating here, and it's clear that you'll
keep going until there's absolutely nothing left.
ChrisA
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