#!/usr/bin/perl
use warnings;
use strict;
use feature ':5.10';


my $hash_ref = { eins => 1, zwei => 2, drei => 3, vier => 4 };

my %hash = %$hash_ref;

say for keys %hash;


my $array_ref = [ 1, 2, 3, 4 ];

my @array = @$array_ref;

say for @array;


my $sub_ref = sub { return 1234; };

# ????? = &$sub_ref();

# my $zahl = sub_routine()