Re: Question about metacharacter '*'

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Subject	Re: Question about metacharacter '*'
From	Rick Johnson <rantingrickjohnson@gmail.com>
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On Sunday, July 6, 2014 10:50:13 AM UTC-5, Devin Jeanpierre wrote:
> In related news, the regexp I gave for numbers will match "1a".

Well of course it matched, because your pattern defines "one
or more consecutive digits". So it will match the "1" of
"1a" and the "11" of "11a" likewise.

As an aside i prefer to only utilize a "character set" when
nothing else will suffice. And in this case r"[0-9][0-9]*"
can be expressed just as correctly  (and less noisy IMHO) as
r"\d\d*".

============================================================
 INTERACTIVE SESSION: Python 2.x
============================================================
# Note: Grouping used for explicitness.

#
# Using character sets:
>>> import re
>>> re.search(r'([0-9][0-9]*)', '1a').groups()
('1',)
>>> re.search(r'([0-9][0-9]*)', '11a').groups()
('11',)
>>> re.search(r'([0-9][0-9]*)', '111aaa222').groups()
('111',)

#
# Same result without charactor sets:
>>> re.search(r'(\d\d*)', '1a').groups()
('1',)
>>> re.search(r'(\d\d*)', '11a').groups()
('11',)
>>> re.search(r'(\d\d*)', '111aaa222').groups()
('111',)

Thread

Question about metacharacter '*' rxjwg98@gmail.com - 2014-07-06 04:51 -0700
  Re: Question about metacharacter '*' Devin Jeanpierre <jeanpierreda@gmail.com> - 2014-07-06 05:09 -0700
    Re: Question about metacharacter '*' rxjwg98@gmail.com - 2014-07-07 11:51 -0700
      Re: Question about metacharacter '*' Devin Jeanpierre <jeanpierreda@gmail.com> - 2014-07-07 13:27 -0700
      Re: Question about metacharacter '*' Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-07-07 22:50 +0100
  Re: Question about metacharacter '*' MRAB <python@mrabarnett.plus.com> - 2014-07-06 16:32 +0100
  Re: Question about metacharacter '*' Devin Jeanpierre <jeanpierreda@gmail.com> - 2014-07-06 08:50 -0700
    Re: Question about metacharacter '*' Rick Johnson <rantingrickjohnson@gmail.com> - 2014-07-06 09:24 -0700
      Re: Question about metacharacter '*' Rick Johnson <rantingrickjohnson@gmail.com> - 2014-07-06 09:32 -0700
      Re: Question about metacharacter '*' Roy Smith <roy@panix.com> - 2014-07-06 12:47 -0400
        Re: Question about metacharacter '*' Rick Johnson <rantingrickjohnson@gmail.com> - 2014-07-06 10:38 -0700
          Re: Question about metacharacter '*' Rick Johnson <rantingrickjohnson@gmail.com> - 2014-07-06 10:58 -0700

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