Dear Monks,

I'm very new to PERL (or programing) and wrote only one script so far. Even though the script runs fine, I have a warning and wish to ask your wisdom to understand it.

The purpose of the script is to parse a log and retrieve the relevant UserID's. After locating the userID in a line in the log I send it to the following sub (AddToUserArray) which inserts it to my user array (only if it wasn't inserted before).

The warning I receive is in the AddToUserArray sub. The warning is: "useless use of private variable in void context at ..." The line it points to is the sub line 18 (yes it only has brackets) 

1 sub AddToUserArray {
2    my $UserID=$_[0];
3    my $i=0;
4    my $Pexists=0;
5    my $Size;
6         
7       if($UserID eq "") { # incase a bad UserID was recived. if Pexi
+sts=1 it will skip &addtouserlog
8            $Pexists=1;
9           return $Pexists;
10        } 
11
12    $Size=scalar(@Participants);
13    for($i;$i<$Size;$i++) {
14        if ($Participants[$i] eq $UserID) {
15            $Pexists=1;
16            last;
17        }    
18    }
19    if ($Pexists==0) {
20        $Participants[$i]=$UserID;
21    }
22    return $Pexists;
23 }

[download]

Again, the entire script works fine but I want to understand this warning.

Thank you!

In reply to Useless use of private variable in void context by okarmi

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