a splitting headache

Mensanator mensanator at aol.com
Thu Oct 22 08:44:35 CEST 2009


On Oct 22, 1:13�am, ru... at yahoo.com wrote:
> On 10/21/2009 11:47 PM, Carl Banks wrote:
>
>
>
>
>
> > On Oct 21, 12:46 pm, David C Ullrich <dullr... at sprynet.com> wrote:
> >> On Tue, 20 Oct 2009 15:22:55 -0700, Mensanator wrote:
> >> > On Oct 20, 1:51 pm, David C Ullrich <dullr... at sprynet.com> wrote:
> >> > I'm not saying either behaviour is wrong, it's just not obvious that the
> >> > one behaviour doesn't follow from the other and the documentation could
> >> > be
> >> > a little clearer on this matter. It might make a bit more sense to
> >> > actually
> >> > mention the slpit(sep) behavior that split() doesn't do.
>
> >> Have you _read_ the docs? They're quite clear on the difference
> >> between no sep (or sep=None) and sep=something:
>
> > Even if the docs do describe the behavior adequately, he has a point
> > that the documents should emphasize the counterintutive split
> > personality of the method better.
>
> > s.split() and s.split(sep) do different things, and there is no string
> > sep that can make s.split(sep) behave like s.split(). �That's not
> > unheard of but it does go against our typical expectations. �It would
> > have been a better library design if s.split() and s.split(sep) were
> > different methods.
>
> > That they are the same method isn't the end of the world but the
> > documentation really ought to emphasize its dual nature.
>
> I would also offer that the example
>
> � '1,,2'.split(',') returns ['1', '', '2'])
>
> could be improved by including a sep instance at the
> beginning or end of the string, like
>
> � '1,,2,'.split(',') returns ['1', '', '2', ''])
>
> since that illustrates another difference between the
> sep and non-sep cases.

But if '1,,2'.split(',') returned ['1', '', '2', ''],
then ','.join(['1', '', '2', '']) would return
'1,,2,' which is not what you started with, so I would
hardly call that an improvement.

The split function works fine, either version, I just
think it could be explained better.




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