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Date: Fri, 03 Jun 2011 23:38:50 +0100
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Subject: Re: how to avoid leading white spaces
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:6979

On 03/06/2011 23:11, Ethan Furman wrote:
> Chris Torek wrote:
>>> On 2011-06-03, rurpy@yahoo.com <rurpy@yahoo.com> wrote:
>> [prefers]
>>>> re.split ('[ ,]', source)
>>
>> This is probably not what you want in dealing with
>> human-created text:
>>
>> >>> re.split('[ ,]', 'foo bar, spam,maps')
>> ['foo', '', 'bar', '', 'spam', 'maps']
>
> I think you've got a typo in there... this is what I get:
>
> --> re.split('[ ,]', 'foo bar, spam,maps')
> ['foo', 'bar', '', 'spam', 'maps']
>
> I would add a * to get rid of that empty element, myself:
> --> re.split('[ ,]*', 'foo bar, spam,maps')
> ['foo', 'bar', 'spam', 'maps']
>
It's better to use + instead of * because you don't want it to be a
zero-width separator. The fact that it works should be treated as an
idiosyncrasy of the current re module, which can't split on a
zero-width match.