entity.pl, third draft

entity.pl

#!/usr/bin/env perl

use strict;
use warnings;
use feature 'say';

use Entity;
use Player;

my $lamp    = Entity->new(name => "lamp");
my $player  = Player->new;

say $player->list_inventory;
$player->obtain($lamp);
say $player->list_inventory;

# this will throw an exception:
# $player->obtain($player);