Hi There I was wondering if you could advise why the following look ahead regex is not working properly. I would not expect the string to match because of the negative look ahead: CODE:

#!/app/perl-5.8/bin/perl

my $string = "ERROR blah license will expire";
print `/app/perl-5.8/bin/perl -version` . "\n\n";
if ( $string =~ /(ERROR.*?(?!(Error processing Cancel Execution|licens
+e will expire)))/ ){
  print "MATCHED\n";
} else {
  print "NOT MATCHED\n";
}

[download]

RESULT: 

$ ./regex.pl

This is perl, v5.8.3 built for sun4-solaris

Copyright 1987-2003, Larry Wall

Perl may be copied only under the terms of either the Artistic License
+ or the
GNU General Public License, which may be found in the Perl 5 source ki
+t.

Complete documentation for Perl, including FAQ lists, should be found 
+on
this system using `man perl' or `perldoc perl'.  If you have access to
+ the
Internet, point your browser at http://www.perl.com/, the Perl Home Pa
+ge.



MATCHED

[download]

Many thanks for your help! Andy

In reply to Regex: negative look ahead by fcaw1

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