Here is yet another way to do this, using callbacks. It simplifies client programming, but requires a coderef to be passed into the method call.

#!/usr/bin/perl -l

use strict;
use warnings;

package Module;

sub new {
    bless { ACLS => {foo => 1, bar => 2} }, shift;
}

sub acls {
    my ($self , $callbackref) = @_;
    while ( my ($k,$v) = each %{ $self->{ACLS} }){
        &$callbackref($k,$v);
    }
}


package main;

my $mod=Module->new;
$mod->acls (
   sub{  print "@_\n";  }
);
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---Output---

bar 2

foo 1
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