asked on

Regex problem

I have the following..

#!/perl -lw
$server = "server";
$status = "Critical";
$critical = "dsmc,,,";
my @data = "dsmc UNIX P3";

      foreach $line (@data)
      {
            ($fs, $msg) = $line =~ /(.*?)\s(.*)/;
            chomp($fs);
            if ($fs =~ /$critical/i)
            {
                  print("$server *TEST* $msg $server - $critical $status");
                  exit; # <--------- It SHOULD exit here, but the regex doesn't appear to match..
            }
      }
      print("$server *TEST* $critical not found in list. No ticket generated.");
      exit;

jmcg

Your pattern in $critical has commas in it while your @data does not. That would be enough to prevent a match.

David Aldridge

ASKER

But if $fs has 'dsmc' as its value, and $critical has 'dsmc,,,' as its value, why doesn't a
regex of $fs =~ /$critical/i match? I don't want an exact match, just match the string
'dsmc'.

David Aldridge

ASKER

ok, I figured it out.. duh.. :) supposed to be $critical =~ /$fs/i

Thanks anyway!

jmcg

I guess that'll work, but based on what you've shown us so far it's a fairly perverse way to go about it.

Regular expressions are great, but when you're checking for an exact sub-match to a string, you're slightly better off using the 'index' operator.

David Aldridge

ASKER

Can you show me how you would plug the index operator in the above script? I'm new to perl and am ALWAYS looking for 'less perverse' ways of doing things. :)

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jmcg

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David Aldridge

ASKER

Yes, I didn't want to post all of the script... its a bit large, so that might account for the oddness. $server, $status and $criical are passed to the script with arguments. @data is read from a text file. One question though.. is the index function not case sensitive?

Thanks for you help and advice!
holein5

jmcg

You're right, I missed the need for a case-insensitive match.

You could do:

if ( index( lc $critical, lc $fs) >= 0 )

but that may start to lose any performance advantage vs the regular expression match. You could omit the 'lc' operator for any string that you already knew for certain didn't need it, such as a string supplied in the script itself.