That was beautiful. I'm writing primarily so more people can see it. I also did a little rewrite that isn't an improvement, per se, but is AWTDI and may help people understand what's going on. (Iterating instead of recursing.)

sub ret_iter {
  my $sub = shift;
  while (my $range = pop) {
    my $inner = $sub;
    $sub = sub { $inner->(@_, $_) for @$range };
  }
  return $sub;
}
[download]

I made it so it changes elements on the right fastest, like a counter.

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