Thank you for pointing that out, I rarely come across List::MoreUtils as it is not a core module so I wasn't aware of part. Very useful if you can work with the resulting AoA but it seems a bit awkward if you really do need separate arrays.

knoppix@Microknoppix:~$ perl -MList::MoreUtils=part -E '
> @parts = part {
>    ++ $i;
>    $i % 5
>    ? $i % 2
>      ? 0
>      : 1
>    : 2
>    } 1 .. 20;
> @odds = @{ $parts[ 0 ] };
> @evens = @{ $parts[ 1 ] };
> @fivers = @{ $parts[ 2 ] };
> say qq{@odds};
> say qq{@evens};
> say qq{@fivers};'
1 3 7 9 11 13 17 19
2 4 6 8 12 14 16 18
5 10 15 20
knoppix@Microknoppix:~$
[download]

knoppix@Microknoppix:~$ perl -E '
> push @{
>    $_ % 5
>    ? $_ % 2
>      ? \ @odds
>      : \ @evens
>    : \ @fivers
>    }, $_ for 1 .. 20;
> say qq{@odds};
> say qq{@evens};
> say qq{@fivers};'
1 3 7 9 11 13 17 19
2 4 6 8 12 14 16 18
5 10 15 20
knoppix@Microknoppix:~$
[download]

Perhaps I'm missing something. I have tried pushing references to @odds etc. onto @parts before using part without success so I can't seem get away from having to do @odds = @{ $parts[ 0 ] }; etc.