It is quicker to return a hash ref, and if you have the hash ref you can still manipulate that hash...just do it like this:

my $buddys = $p->BuddyList; #this returns a hash ref
for (keys %{$buddys})
{
    print "GROUP: $_\n";  #I'm asuming that 'keys' here was a reference to $keys in your foreach...
    print "NAMES: ", join (' ', @{$buddys->{$_}}), "\n";  #similarly, I removed $keys and so I'm using $_
}

This gives you the speed of using a reference (incedentally, for only a few pieces of punctuation more, you can do the same thing with Indenties and use an arrayref), along with the ease of an actual hash (in the end, that's what it is). you could feasibly get away with

foreach ( keys %$buddys )

Note that, in general, if foo returns a hashref, you can get the hash (if you *really* need it) by using braces judiciously, e.g.

my %hash = %{foo(@args_to_foo)};
# or, with a method that returns a hashref
my %hash = %{$object->foo};
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Either way, though, you lose some of the speed advantages of passing around references.

Philosophy can be made out of anything. Or less -- Jerry A. Fodor

sub hash {
        my $h = shift;
        return %$h;
}

sub href {
        my $h = shift;
        return $h;
}

my $n = { moo => 'blah', arrg => 'no' };
my %hash = hash($n);
$hash{arrg} = 'yes';
print join(' ',%$n) . "\n";
# Output: moo blah arrg no

my $m = { moo => 'blah', arrg => 'no' };
my $hash = href($m);
$hash->{arrg} = 'yes';
print join(' ',%$m) . "\n";
# Output: moo blah arrg yes
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