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From: jm36+@andrew.cmu.edu (John Gardiner Myers)
Newsgroups: comp.lang.perl
Subject: Re: regular expressions
Message-ID: <kcHaBR200WBw4gd8YO@andrew.cmu.edu>
Date: 6 Jun 91 16:31:25 GMT
References: <1991Jun4.175023.6509@serval.net.wsu.edu>
Organization: Computer Science, Carnegie Mellon, Pittsburgh, PA
Lines: 5

In article <1991Jun4.175023.6509@serval.net.wsu.edu> hakimian@tek4.eecs.wsu.edu (Karl Hakimian - staff) writes:
>For example, how would you write a regular expression that accepts a string
>with "foo" iff "bar" is not also in the string.

 /^([^b]|b[^a]|ba[^r])*b?a?foo([^b]|b[^a]|ba[^r])*$/