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From: merlyn@iWarp.intel.com (Randal L. Schwartz)
Newsgroups: comp.lang.perl
Subject: Re: regular expressions
Message-ID: <1991Jun4.213051.5097@iWarp.intel.com>
Date: 4 Jun 91 21:30:51 GMT
References: <1991Jun4.175023.6509@serval.net.wsu.edu>
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Reply-To: merlyn@iWarp.intel.com (Randal L. Schwartz)
Organization: Stonehenge; netaccess via Intel, Beaverton, Oregon, USA
Lines: 21
In-Reply-To: hakimian@tek4.eecs.wsu.edu (Karl Hakimian - staff)
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In article <1991Jun4.175023.6509@serval.net.wsu.edu>, hakimian@tek4 (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.

There's no trivial way to do it, unless you count

	if (/foo/ && !/bar/) {
		# yes!
	} else {
		# no (sigh)
	}

as your (literal) solution.  Regexs have a hard time saying "not this
thing here", unless the "thing" is a single character.

print "Just another Perl hacker," unless /foo/ && !/bar/
-- 
/=Randal L. Schwartz, Stonehenge Consulting Services (503)777-0095 ==========\
| on contract to Intel's iWarp project, Beaverton, Oregon, USA, Sol III      |
| merlyn@iwarp.intel.com ...!any-MX-mailer-like-uunet!iwarp.intel.com!merlyn |
\=Cute Quote: "Intel: putting the 'backward' in 'backward compatible'..."====/