ok, I see what's what now after I look inside , its much like choroba wrote , %seen 
sub next_multiset {
  my $self = shift;

  if ( ! $self->{frequency} ) {
    print STDERR "must use next_combination() if 'frequency' argument 
+not passed to constructor\n";
    return ();
  }

  my $data = $self->data();
  my $compare = $self->compare();

  while ( my @combo = $self->_next_combination ) {
    my $x = join '', map {scalar($$_)} sort @$data;
    my $y = join '', map {scalar($_) } sort @combo;

    next if $self->{'cache_multiset'}{$y}++;
    return @combo;
  }
  $self->{'cache_multiset'} = undef;
  return ();
}

[download]

so Algorithm::Combinatorics doesn't appear to support that(%seen) out of the box (I see no cache, no hv)

In reply to Re^5: Wordfeud racks by Anonymous Monk
in thread Wordfeud racks by Anonymous Monk

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