Re: filter a list of strings

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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

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filter a list of strings <c.buhtz@posteo.jp> - 2015-12-03 02:15 +0100
  Re: filter a list of strings Jussi Piitulainen <harvesting@is.invalid> - 2015-12-03 08:32 +0200
    Re: filter a list of strings <c.buhtz@posteo.jp> - 2015-12-03 10:27 +0100
      Re: filter a list of strings Jussi Piitulainen <harvesting@is.invalid> - 2015-12-03 13:53 +0200
      Re: filter a list of strings Peter Pearson <pkpearson@nowhere.invalid> - 2015-12-05 19:42 +0000
    Re: filter a list of strings Chris Angelico <rosuav@gmail.com> - 2015-12-03 20:40 +1100
    Re: filter a list of strings Wolfgang Maier <wolfgang.maier@biologie.uni-freiburg.de> - 2015-12-03 10:46 +0100
    Re: filter a list of strings Laura Creighton <lac@openend.se> - 2015-12-03 10:53 +0100
    Re: filter a list of strings jmp <jeanmichel@sequans.com> - 2015-12-03 11:03 +0100
    Re: filter a list of strings Peter Otten <__peter__@web.de> - 2015-12-03 11:13 +0100
    Re: filter a list of strings Denis McMahon <denismfmcmahon@gmail.com> - 2015-12-03 14:16 +0000
      Re: filter a list of strings Jussi Piitulainen <harvesting@is.invalid> - 2015-12-03 17:02 +0200
  Re: filter a list of strings Grobu <snailcoder@retrosite.invalid> - 2015-12-03 13:17 +0100

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