The following might help to make things a little more clear. Hash has 2 values, which are both hash references (to a anonymous hashes { drinks => 1 } and { drinks => 2 }). When you do the shallow copy, the hash references are copied, but they still refer to the same hashes in both %hash and %copy: 
use strict;
my %hash = ();
$hash{a}{drinks}=1;
$hash{b}{drinks}=2;

my $p = \%hash;
my %copy = %{ $p };

print "ref hash: ", \%hash, "\nref copy: ", \%copy, "\n";
print "values hash: ",join(", ", values %hash), "\nvalues copy: ",join
+(", ", values %copy), "\n";

[download]
Prints: 
copy: ab
hash: ab
ref hash: HASH(0x82ef7d8)
ref copy: HASH(0x82ef928)
values hash: HASH(0x82e0308), HASH(0x82ef788)
values copy: HASH(0x82e0308), HASH(0x82ef788)

[download]
Note that the values are identical, and thus the values of %hash and %copy refer to the same hash references.

In reply to Re: hash ref mind blow by duckyd
in thread hash ref mind blow by Anonymous Monk

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