Re: [boost] [regex and string algo] spliting empty string (was: again strange split behaviour)

From: Pavol Droba (droba_at_[hidden])
Date: 2005-07-13 16:08:19

On Wed, Jul 13, 2005 at 09:22:17PM +0300, Peter Dimov wrote:
> Pavol Droba wrote:
> > Hi,
> >
> > This is an interesting observation. So it seems reasonable to drop
> > back to 1.32 version.
> 
> The only reasonable thing is for split to return N+1 pieces for a string 
> with N separators, if you ask me. :-) This is lossless in the sense that it 
> allows you to reconstruct the original string. The non-reasonable behavior 
> can easily be implemented on top of that, but not vice versa. 
> 

Reading your replies and thinking about it a little bit, I come to conclusion,
that the definition above is realy to only reasonable one. That was actualy
also the reason why I have altered the behaviour in this release. Beacuse
I considered the former one as wrong.

But now there is still issue about the empty string. I think, that both approaches
- returning no token
- returing one empty token 

have some meaning.

The second one is very similar to returnig an empty token at the end if the input
string ends with a separator.

The first one simply tells that nothing equals nothing. 
Yet I prefer the second approach, since it is more on par with the current reasoning.

Does anybody have some arguments/reasoning that can help here?

Regards,
Pavol