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From: Grobu <snailcoder@retrosite.invalid>
Newsgroups: comp.lang.python
Subject: Re: filter a list of strings
Date: Thu, 03 Dec 2015 13:17:30 +0100
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On 03/12/15 02:15, c.buhtz@posteo.jp wrote:
> I would like to know how this could be done more elegant/pythonic.
>
> I have a big list (over 10.000 items) with strings (each 100 to 300
> chars long) and want to filter them.
>
> list = .....
>
> for item in list[:]:
>    if 'Banana' in item:
>       list.remove(item)
>    if 'Car' in item:
>       list.remove(item)
>
> There are a lot of more conditions of course. This is just example code.
> It doesn't look nice to me. To much redundance.
>
> btw: Is it correct to iterate over a copy (list[:]) of that string list
> and not the original one?
>

No idea how 'Pythonic' this would be considered, but you could use a 
combination of filter() with a regular expression :

# ------------------------------------------------------------------
import re

list = ...

pattern = re.compile( r'banana|car', re.I )
filtered_list = filter( lambda line: not pattern.search(line), list )
# ------------------------------------------------------------------

HTH