Hello,

Thanks for your reply. Interestingly, I'm not getting a different result when adding parenthisis for the append() call, but when I use parenthesis for the call to list_iterator, it DOES fix my problem.

my $it3 = append (upto(1,3), list_iterator qw(foo bar baz), upto (7,9)
+);
print_it $it3;
[download]

prints:

Invalid append 1
$VAR1 = 1;
$VAR1 = 2;
$VAR1 = 3;
$VAR1 = 'foo';
$VAR1 = 'bar';
$VAR1 = 'baz';
$VAR1 = sub {
            use warnings;
            use strict 'refs';
            return $start <= $end ? $start++ : undef;
        };
[download]

But when I use parenthesis around list_iterator:

print "\n\nInvalid append 1\n";
my $it3 = append upto(1,3), list_iterator (qw(foo bar baz)), upto (7,9
+);
print_it $it3;
[download]

I get what I would expect

Invalid append 1
$VAR1 = 1;
$VAR1 = 2;
$VAR1 = 3;
$VAR1 = 'foo';
$VAR1 = 'bar';
$VAR1 = 'baz';
$VAR1 = 7;
$VAR1 = 8;
$VAR1 = 9;
[download]

Thanks for the assist! I think the problem is trying to make too many calls to subs without parenthesis.