You don't know the last element ... but you know the first. Using that knowledge, you can enhance your logic as follows:

my $first = 0;                         # a flag to remember the first 
+element

while(elements to check) {             # *
  if (elem should be printed) {        # *

     if ($first == 0) { $first = 1; }  # don't print a comma before th
+e first element
     else             { print ",";  }  # print a comma

     print elem                        # *
  }
}

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HTH, Rata

Update: marked the pseudocode of the original poster with # * to reduce confusion

In reply to Re: printing lists... by Ratazong
in thread printing lists... by daverave

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