#!/usr/bin/perl

use strict;
use warnings;
use Data::Dump;

my %testHash;                # initialize hash
my $hashRef = \%testHash;    # get a reference to that

$hashRef->{'a'} = "Hello World!";

my $destref = \$hashRef->{'b'}; # Just a reference to the value, no dereference involved.

# initialize hash element as empty array
$$destref = [];				# NOTE: this line is not necessary

# assign a value to the hash element 'a'
@{$$destref}[0] = "How";            # Assign to the dereference.
@{$$destref}[1] = "are";            # Assign to the dereference.

# initialize array element as empty hash
@{$$destref}[2] = { };		# NOTE: this line *is* necessary	

@{$$destref}[2]->{'c'} = "you";			# assign values to hash
@{$$destref}[2]->{'d'} = "today?";		#


dd \%testHash;

# Output:
# {
#   a => "Hello World!",
#   b => ["How", "are", { c => "you", d => "today?" }],
# }