test.pl
sub beispiel {
 @array= (was, wie,wo,wann,wozu,wieso);
  foreach $array(@array) {
  return $array;
   }
}
#hautprogramm
$give_the_next_string = beispiel...; #to complete

my $next_index = sub {
       my @array= (was, wie,wo,wann,wozu,wieso);
       return defined $array[$_[0]+1] ? $array[$_[0]+1] : $array[0];
}

$callback = $next_index->(2);

#!/usr/bin/perl

use strict;
use warnings;

use Data::Dumper;

sub iterator (@) {
    my @items = @_;
    return sub { return shift @items };
} 

my $next_item = iterator qw/foo bar buz/;
print Dumper $next_item->() for 0..3;

sub beispiel {
    my $zaehler;
    @array= (was, wie,wo,wann,wozu,wieso);
    return = sub {
        $zaehler = 0 if scalar @array > $zaehler;
        return $array[$zaehler++];
    }
}
$frager = beispiel();
$erste_antwort = $frager();
$zweite_antwort = $frager();

my $next_index = sub {
      my @array= (was, wie,wo,wann,wozu,wieso);
      return defined $array[$_[0]+1] ? $array[$_[0]+1] : $array[0];
}

$callback = $next_index->(2);

package liste;
sub new
{
  my $self={list=>[@_]};
  bless($self);
  return $self;
}

sub next
{
  my $self=shift(@_);
  my $l=$self->{list};
  push(@$l,shift(@$l));
  return $$l[0];
}

sub before
{
  my $self=shift(@_);
  my $l=$self->{list};
  unshift(@$l,pop(@$l));
  return $$l[0];
}

sub now
{ 
  my $self=shift(@_);
  return $$self->{list}[0];
}
package main;

my $list=liste::new(was, wie,wo,wann,wozu,wieso);

for(0..6)
{
  print $list->next();
  print "\n";
}