#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;
use feature 'say';
use Data::DRef qw( :dref_access :key_access );

my $complex = {
    key_of_hash => {
	opt1 => 'val1',
	opt2 => 'val2',
	key_of_hash_of_hashes => {
	    opt3 => 'val3',
	    opt4 => 'val4',
	}
    },
    key_of_arr => [
	38,
	'abc',
	-1829,
	['element0',
	 8979,
	 'something else']
	]
};

# say get_value_for_dref($complex, 'key_of_arr.3.0');
# print Dumper get_value_for_key($complex, 'key_of_hash');
# say get_value_for_keys($complex, 'key_of_hash', 'key_of_hash_of_hashes', 'opt3');
# print Dumper $complex;