From: shaman <noone@...>
Date: 2008-07-03T19:22:00+09:00
Subject: Re: yet another regexp problem

Srijayanth Sridhar pisze:

 > /([a-z]{3})[02-9][0-9]{2}\1/
 >
 > Should work.
> irb(main):008:0> m
> => /([a-z]{3})[02-9][0-9]{2}\1/
> irb(main):009:0> a='xxx765xxx'
> => "xxx765xxx"
> irb(main):010:0> b='vvv123vvv'
> => "vvv123vvv"
> irb(main):011:0> a.match(m)
> => #<MatchData:0xb7dc0354>
> irb(main):012:0> puts a.match(m)
> xxx765xxx
> => nil
> irb(main):013:0> puts b.match(m)
> nil
> => nil
> 

it's not so easy because "vvv133vvv" also should match but your 
expression return nil :(


irb(main):001:0> reg = /([a-z]{3})[02-9][0-9]{2}\1/
=> /([a-z]{3})[02-9][0-9]{2}\1/
irb(main):002:0> a = "vvv123xxx"
=> "vvv123xxx"
irb(main):003:0> puts a.match(reg)
nil
=> nil
irb(main):004:0> b = "vvv133xxx"
=> "vvv133xxx"
irb(main):005:0> puts b.match(reg)
nil
=> nil

numer 123 is the only one should not match.