742.pl

#!/usr/bin/env perl

use strict;
use warnings;
use 5.010;

use Data::Dumper;
$Data::Dumper::Sortkeys = 1;
$Data::Dumper::Terse = 1;
$Data::Dumper::Indent = 1;
$Data::Dumper::Quotekeys = 1;
sub dmp { say &Dumper; };

my $t = TestHash->new ();
$$t{w} = 2;
dmp ($t, {%$t});

package TestHash;
{
    use overload
        '%{}' => 'to_hash',
        fallback => 1;

    sub to_hash {
        my ($self, ) = @_;
        return $$self[0];
    }

    sub new {
        my $self = [{ q => 1, }];
        return bless $self, $_[0];
    }
}