Reg Experts!

Just going through Narbik's Regular Expression listings and using INE "Understanding BGP Regular Expressions" for reference.

I have some questions if anyone can explain in people terms. Here goes.

What's the difference between?
       deny ^200_300$
       deny _200_300$

       ^([0-9]+)?$
       ^([0-9]+)(_1\)*$

       _100+
       ^([0-9]+)(_\1)*$

In regards to ^([0-9]+)(_\1)*$ why is the number 1 chosen? Why have it at all? Why not have a 0 or a 2 in there? I'm still looking through documentation on \.

Any help is appreciated, thanks!
JB

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Received on Wed Jun 09 2010 - 12:18:54 ART