Hello monks, I have the following code, taken from some examples in the Higher Order Perl book. Module Iterator_Utils.pm:

 

package Iterator_Utils;

require Exporter;

use base 'Exporter';

@EXPORT_OK = qw(append nextval Iterator
                imap igrep
                iterate_function filehandle_iterator list_iterator);

%EXPORT_TAGS = ('all' => \@EXPORT_OK);

use strict;
use warnings;

<sub Iterator (&) { return $_[0] }
 ...
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This is used in the following way:

#!/usr/bin/perl -w

package FlatDB::Iterator;

require Iterator_Utils;
use strict;
use warnings;

my $FIELDSEP = qr/\s+/;

#sub Iterator (&) { return $_[0] }

sub query {
    my $self = shift;
    my ($field, $value) = @_;
    my $fieldnum = $self->{FIELDNUM}{uc $field};
    return unless(defined($fieldnum));
    my $it = $self->{FH};
    return Iterator { 
        local $_;
        while(defined($_=Iterator_Utils::nextval($it))) {
            my @fields = split($self->{FIELDSEP});
            my $fieldval = $fields[$fieldnum];
            return $_ if($fieldval eq $value);
        }
        return;
    };
}
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When used like this, the query function returns a value (the value resulting from executing the code inside the Iterator body), instead of the anonymous sub i was expecting. If i declare the Iterator function locally, instead of using the one from the Iterator_Utils module, everything works all right.

Am I missing anything here? Is this the way it should behave?