use strict;
use warnings;

my $obj = Foo->new();

for my $key (keys %{$obj->{acls}})
{
        print "$key\n";
}

package Foo;

sub new
{
        my $self = shift;
        my %obj = (     acls => { a=>1,
                                  b=>2 }        );
        return bless \%obj;
}

##</code><code>##

use strict;
use warnings;

my $obj = Foo->new();

for my $key (keys %{$obj->{acls}})
{
        print "$key\n";
}
for my $key (keys %{$obj->acls})
{
        print "$key\n";
}

package Foo;

sub new
{
        my $self = shift;
        my %obj = (     acls => { a=>1,
                                  b=>2 }        );
        return bless \%obj;
}

sub acls
{
        my $self = shift;
        return \%{$self->{acls}};
}