From: "Ara.T.Howard" <ahoward@...>
Date: 2004-04-07T01:04:18+09:00
Subject: Re: Bug in sub?

On Tue, 6 Apr 2004, Martin Hart wrote:

> On Tuesday 06 Apr 2004 3:01 pm, Robert Feldt wrote:
> >
> > Yeah, that's right the "last matched group"; I don't use that one much
> > apparently...
> >
> 
> Sorry, call me thick but I don't understand that :-)
> 
> Did Guy confirm that it was a bug, or show that it is not a bug?

 __not_a_bug__ # that's python for not a bug


svg% ruby -e 'p "abcdef".sub(/(.)./, "\\+")'
"acdef"
svg%


  /(.)./ and '\+'

    - match a char, followed by another char. remember the first char
    - replace the entire match with the remembered first char

    abcdef -> acdef
    --         
    -         -

svg% ruby -e 'p "abcdef".sub(/(.).(..)/, "\\+")'
"cdef"
svg% 


  /(.).(..)/ and '\+'

    - match a char, followed by another char. followed by two more chars.
      remember the last two chars (and the first) 
    - replace the entire match with the remembered last two chars  (which is
      the 'last matched group')

    abcdef -> cdef
    ----        
      --      --



-a
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