try checking the parameters before the split

while (defined($ARGV[0])) {
   my $opt = shift;

   if($opt eq '-f') {
     my ($username, $domain) = split(/@/, shift);
   }
   else {
     die("Usage: <username\@domain>\n");
   }a
}

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In reply to Re: Validating command-line _parameters_ (not options) by Anonymous Monk
in thread Validating command-line _parameters_ (not options) by dserodio

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