#!/usr/bin/perl -w
                                                                                
use strict;
use warnings;
use Data::Dumper;
                                                                                
my %hash = ( 'test', 'program' );
print Dumper($hash);                #  Error: should be \%hash
                                                                                
__END__
== Output ==
Global symbol "$hash" requires explicit package name at hash_test line 8.