#! /usr/bin/env perl
use strict;
use warnings;

use Data::Dumper;


my %data = (
    what => [
        1,2,3
    ],
    ever => [
        qw( a b c )
    ],
);

my $file = "/tmp/filename.txt";


### save %data to file as %name
open my $wh, '>', $file or die "open($file,w) failed: $!";
print $wh Data::Dumper->Dump( [ \%data ], [ "*name" ] );
close $wh or die "close($file) failed: $!";


### read to a lexical variable
### retrieve %name from file (you need to know %name before)
open my $rh, '<', $file or die "open($file,r) failed: $!";
my %name;
eval do { local $/; <$rh> };
close $rh;

print Data::Dumper->Dump( [ \%name ], [ '*name_it' ] );