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Re: Groups in regular expressions don't repeat as expected

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On 2011-04-20, John Nagle <nagle@animats.com> wrote:
> Here's something that surprised me about Python regular expressions.
>
> >>> krex = re.compile(r"^([a-z])+$")
> >>> s = "abcdef"
> >>> ms = krex.match(s)
> >>> ms.groups()
> ('f',)
>
> The parentheses indicate a capturing group within the
> regular expression, and the "+" indicates that the
> group can appear one or more times.  The regular
> expression matches that way.  But instead of returning
> a captured group for each character, it returns only the
> last one.
>
> The documentation in fact says that, at
>
> http://docs.python.org/library/re.html
>
> "If a group is contained in a part of the pattern that matched multiple 
> times, the last match is returned."
>
> That's kind of lame, though. I'd expect that there would be some way
> to retrieve all matches.

.findall

-- 
Neil Cerutti

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Groups in regular expressions don't repeat as expected John Nagle <nagle@animats.com> - 2011-04-20 12:20 -0700
  Re: Groups in regular expressions don't repeat as expected Neil Cerutti <neilc@norwich.edu> - 2011-04-20 19:23 +0000
    Re: Groups in regular expressions don't repeat as expected John Nagle <nagle@animats.com> - 2011-04-20 13:34 -0700
      Re: Groups in regular expressions don't repeat as expected Neil Cerutti <neilc@norwich.edu> - 2011-04-21 13:16 +0000
        Re: Groups in regular expressions don't repeat as expected John Nagle <nagle@animats.com> - 2011-04-24 12:43 -0700
  Re: Groups in regular expressions don't repeat as expected MRAB <python@mrabarnett.plus.com> - 2011-04-20 21:03 +0100
  Re: Groups in regular expressions don't repeat as expected Vlastimil Brom <vlastimil.brom@gmail.com> - 2011-04-21 15:57 +0200
  Re: Groups in regular expressions don't repeat as expected Vlastimil Brom <vlastimil.brom@gmail.com> - 2011-04-21 20:36 +0200

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