On 2008-11-03 12:12, M.-A. Lemburg wrote:
>> 一首诗 wrote:
>>> Hi all,
>>>
>>> Today I wrote some code like this:
>>>
>>> for m in self.messages:
>>> if not m.finished:
>>> continue
>>>
>>> #process the message
>>>
>>> fini = [m for m in self.messages if m.finished]
>>> for m in fini:
>>> self.messages.remove(m)
>>>
>>> As you can, I want to find these finished messages in
>>> "self.messages",
>>> process them, and then remove them from the list.
>>>
>>> Because a list can not be modified while iterating it, I have to use
>>> a list "fini" to accomplish the target.
>>>
>>> I found a smell of bad performance here.
>>> Is there any faster ways?
>
> The typical way to do this is to iterate over the list in reverse
> order and then using the item index as basis for removing the
> item:
>
> for i, item in enumerate(reversed(mylist)):
> # process item
> del mylist[i]
Sorry, the above should read:
for i, item in reversed(enumerate(mylist)):
# process item
del mylist[i]
--
Marc-Andre Lemburg
eGenix.com
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