From: "Ara.T.Howard" <ahoward@...>
Date: 2004-05-15T01:53:56+09:00
Subject: Re: Regexp Error?

On Fri, 14 May 2004, Kristof Bastiaensen wrote:

> On Fri, 14 May 2004 08:54:22 -0600, Ara.T.Howard wrote:
> > 
> > what guy is saying here is that __unless__ both '(.*)' __and__ '.*' match in
> > the above - you don't have match.  we all agree that the '(.*)' matches the
> > entire 'abc' and we all agree that the pattern '(.*).*' matches 'abc' -
> > therefore we all agree that it's correct that certain pattern match zero width
> > positions in strings and consume no chars whilst still matching.  
> 
> Agree until here.
> 
> > therefore we
> > all agree that
> > 
> >   '123-456'.gsub /.*$/, 'X' => 'XX'
> > 
> > because if it __didn't__ '(.*).*' could not match 'abc'
> > 
> > 
> > -a
> 
> I don't agree.  The things is, you can't really consume 'nothing'.
> If I follow your reasoning, the above should give 'XXX', because
> 123-456 matches /(.*)(.*)(.*)/.  How much empty spaces are there between
> two characters?  One, three, infinite? There have to be rules, and I would
> find the following the most logical one:
> 
> * when the empty space is already matched before, don't match
> again, unless explicitly against ? or *.  (gawk behaviour?)
> 
> Kristof

but then

  /^$/ would not match ''

empty tokens must not consume and must stack

-a

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