On Sun, Sep 14, 2014 at 1:27 AM, Ian Kelly <[email protected]> wrote:
> On Sat, Sep 13, 2014 at 1:39 AM, Michael Welle <[email protected]> wrote:
>>> 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.
>> Ah, that looks like a good approach, thank you.
>
> Also note that this approach (appending to the end and popping from
> the front) will be more efficient using a collections.deque than a
> list.
Sure it will - that's kinda the point of a double-ended queue, to
avoid all the inefficient movements :) But the concept is still the
same: do repeated mutations rather than iteration. Either that, or
iterate and build up a new list, either with a comprehension or with
something like this:
newlst = []
for element in lst:
# work with element
newlst.append(new_element)
ChrisA
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