use strict;
use warnings;
my $chapters = {
   one => 'Chapter 1: AAA',
   two => 'Chapter 2: BBB',
   three => 'Chapter 3: CCC',
};
say "We start with $chapters->{noe}";   # Compiler neither gives an error, nor a warning.

##</code><code>##

package chapters;
our $one = 'Chapter 1: AAA';
our $two = 'Chapter 2: BBB';
our $three = 'Chapter 3: CCC';
package main;
use strict;
use warnings;
say "We start with $chapters::noe";  # Compile time error.