You can even do the uniqe test using grep as you add items. This is also a wasteful approach but maybe easier on memory usage if the log file that you are processing is large. 
    if ($line =~ /Login succeeded. User: (\w+)/i) {
        my $user = $1;
        push @users, $user unless grep (/$user/i, @users);
    }

[download]
Using a hash is the best plan.

In reply to Re^4: array processing by inman
in thread array processing by Anonymous Monk

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