> For the complete documentation index, see [llms.txt](https://trizen.gitbook.io/perl6-rosettacode/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://trizen.gitbook.io/perl6-rosettacode/programming_tasks/g/generator/exponential.md).

# Exponential

As with Haskell, generators are disguised as lazy lists in Raku.

```perl
sub powers($m) { 0..* X** $m }

my @squares = powers(2);
my @cubes   = powers(3);

sub infix:<with-out> (@orig, @veto) {
    gather for @veto -> $veto {
        take @orig.shift while @orig[0] before $veto;
        @orig.shift if @orig[0] eqv $veto;
    }
}

say (@squares with-out @cubes)[20 ..^ 20+10].join(', ');
```

#### Output:

```
529, 576, 625, 676, 784, 841, 900, 961, 1024, 1089
```