Note that Perl is not Visual Basic. ,, does not create an empty element:

use strict;
use Data::Dumper;
sub print_args {
    print Dumper \@_;
};

print "Plain:\n";
print_args( 'foo', 'bar' );
print "With ',,':\n";
print_args( 'foo',, 'bar' );
print "Explicit:\n";
print_args( 'foo', undef, 'bar' );
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