#!/usr/bin/perl
use strict;
use warnings;

my $count_1  = iterator( 1 );
print $count_1->(), "\n" for 1 .. 10;

my $count_2  = iterator( 'a' );
print $count_2->(), "\n" for  1 .. 10;

sub iterator {
    my $iterator = shift;
    return sub { $iterator++ };
}