From: David Alan Black <dblack@...>
Date: 2004-05-12T20:18:54+09:00
Subject: Re: Strange regexp behaviour in gsub

Hi --

Joel VanderWerf <vjoel@PATH.Berkeley.EDU> writes:

> David Alan Black wrote:
> > Hi --
> > 
> > Kristof Bastiaensen <kristof@vleeuwen.org> writes:
> > 
> > 
> >>I was thinking more about something like variable-width look-between :-)
> >>Meaning for example a(?^\w+)b would match any a(.*)b if (.*) is
> >>not equal to (\w+)
> > 
> > 
> > For that particular case you can use \W (opposite of \w):
> > 
> >   /a\W*b/  # a + zero or more non-\w + b
> 
> Not quite the same:
> 
> /a\W*b/ =~ "a%xb"
> # => nil

Whoops :-)

> It sounded like the OP wanted an re that matched "a%xb", because "%x" is 
> "not equal to (\w+)". Sort of like:
> 
> /a(?!\w+b).*b/ =~ "a%xb"
> # => 0

Yes, you're right, though I'm driven to find something that doesn't
involve repeating the 'b'.  Current iteration:

  /a(.*\W.*)?b/.match("a%xb")
  # => #<MatchData:0x4019d298>

(possibly with *?'s instead of *'s, depending on the OP's needs)


David

-- 
David A. Black
dblack@wobblini.net