I have a file containing records separated by a |.
In order to classify these entries, I first split each line, and match certain fields against a hash of filters.

The filters are loaded from a configuration file at run-time.
I am thus limited to $var[5] =~ /$regex/ (or at least I think so) for my matching.
Is it possible to get something like this to work: 

$re[0] = qr (.*(?!system))i;
$re[1] = qr (system)i;
$v[0] = "oneitem";
$v[1] = "anothersystem";

for $a (@v) {
  for $r (@re) {
    print "\nRegex: $r\tValue: $a\n";
    if ($a =~ /$r/) {
      print "$a matches $r\n" ;
    }
  }
}

[download]

As this results in:

Regex: (?-xism:.*(?!system))    Value: oneitem
oneitem matches (?-xism:.*(?!system))

Regex: (?-xism:system)  Value: oneitem

Regex: (?-xism:.*(?!system))    Value: anothersystem
anothersystem matches (?-xism:.*(?!system))

Regex: (?-xism:system)  Value: anothersystem
anothersystem matches (?-xism:system)

[download]

Which is not what I want...
Is it possible to construct a regex that "matches if doesn't contain" ?

In reply to Backtracking problem with .*(?!bar) by olivierp

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