#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;

my %cnf = (state_file => 'state.txt');

my $first_num = 10.0095;
my $last_num  = 72.0967;
my $mem_first = q{77xptj52};
my %hash      = (one => 1);
my @array     = qw{one two three};

save_state(
  {
    first_num => $first_num, 
    last_num => $last_num, 
    mem_first => $mem_first,
    hash => \%hash,
    array => \@array,
  }
);

my $state = load_state();

print "first_num: $state->{first_num}\n";
print Dumper $state;

sub save_state{
  my ($state) = @_;
  my $state_file = $cnf{state_file};
  open my $fh, '>', $state_file
    or die $!;
  print $fh Data::Dumper->Dump([$state], [qw(S)]);
  close $fh;
}

sub load_state {  
  our $S;
  my $state_file = $cnf{state_file};
  if (-e $state_file){
    eval {do $state_file};
    die $@ if $@;
  }
  else{
    $S = {time => time};
  }
  return $S;
}