At 10:10 AM 6/7/01 -0700, Paul wrote:
>  .   matches the r in supernova
>  n+  matches one or more n's, so it matches the n in supernova
>  .   matches the o in supervova
>  .?  matches one or no characters, so it matches nothing
>     (successfully, twice)
>  v*  matches any number of v's, including zero,
>      so it matches the v in supernova
>  . matches the a in supernova.

Not that it would be possible to tell the difference in this case without 
using -Dr, but I beg to disagree with this analysis, and point out my own 
previously posted instead.  The key difference is that ? is greedy and 
backtracking is involved.  Important stuff for a regex user to understand, 
though.

--
Peter Scott
Pacific Systems Design Technologies
http://www.perldebugged.com

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