foo.pl

#! /usr/bin/env perl

use strict;
use warnings;

use feature 'say';
use DDP;
use YAML::XS qw/ DumpFile LoadFile /;

my $file = './aoa.yaml';

if ( -e $file ) {
  my $data = LoadFile($file);
  p $data;
}
else {
  my $data = [ [ 1 .. 3 ], [ 4 .. 6 ] ];
  DumpFile($file, $data);
  say "Look at $file...";
}

gistfile1.txt

irving:~/Desktop
☹ [ 0 ] % ./foo.pl                                                                                                                                                                                                                                                                                                                                                                                                                 18:16:14
Look at ./aoa.yaml...

irving:~/Desktop
☺ % cat aoa.yaml                                                                                                                                                                                                                                                                                                                                                                                                                   18:16:26
---
- - 1
  - 2
  - 3
- - 4
  - 5
  - 6

irving:~/Desktop
☺ % ./foo.pl                                                                                                                                                                                                                                                                                                                                                                                                                       18:16:28
\ [
    [0] [
        [0] 1,
        [1] 2,
        [2] 3
    ],
    [1] [
        [0] 4,
        [1] 5,
        [2] 6
    ]
]