yay closures!

use Algorithm::Loops qw( NestedLoops );


sub create_iterator_closure {
   my $p = $_[0]*2-1;
   return sub { [ $_+1..$p ] };
}


sub output {
   my @args = @_;
   local $, = ", ";
   local $\ = "\n";
   print(@args);
   return 1;
}


{
   my $depth = 4;
   my @iters;

   push(@iters, [ 0..1 ]);
   push(@iters, create_iterator_closure($_)) foreach (2..$depth);

   NestedLoops(\@iters, \&output);
}

__END__
Output
======
0, 1, 2, 3
0, 1, 2, 4
0, 1, 2, 5
0, 1, 2, 6
0, 1, 2, 7
0, 1, 3, 4
0, 1, 3, 5
0, 1, 3, 6
0, 1, 3, 7
0, 1, 4, 5
0, 1, 4, 6
0, 1, 4, 7
0, 1, 5, 6
0, 1, 5, 7
0, 2, 3, 4
0, 2, 3, 5
0, 2, 3, 6
0, 2, 3, 7
0, 2, 4, 5
0, 2, 4, 6
0, 2, 4, 7
0, 2, 5, 6
0, 2, 5, 7
0, 3, 4, 5
0, 3, 4, 6
0, 3, 4, 7
0, 3, 5, 6
0, 3, 5, 7
1, 2, 3, 4
1, 2, 3, 5
1, 2, 3, 6
1, 2, 3, 7
1, 2, 4, 5
1, 2, 4, 6
1, 2, 4, 7
1, 2, 5, 6
1, 2, 5, 7
1, 3, 4, 5
1, 3, 4, 6
1, 3, 4, 7
1, 3, 5, 6
1, 3, 5, 7
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