Unless the way you are passing the parameters is different from what you have shown, I am not certain that you are getting the data you expect into these variables.

use strict;
use warnings;

use Data::Dumper;
$Data::Dumper::Indent = 1;

sub testme {
  my ($a, @b, @c) = @_;

  print Dumper(\$a, \@b, \@c);
}

print "===== 1 ======\n";

testme("a", qw(b c d), qw(e f g));
 
print "===== 2 ======\n";

testme("a", ('b', 'c', 'd'), ('e', 'f', 'g'));
__DATA__
===== 1 ======
$VAR1 = \'a';
$VAR2 = [
  'b',
  'c',
  'd',
  'e',
  'f',
  'g'
];
$VAR3 = [];
===== 2 ======
$VAR1 = \'a';
$VAR2 = [
  'b',
  'c',
  'd',
  'e',
  'f',
  'g'
];
$VAR3 = [];
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