# N-hashes code adapted from docs to Class::Std
sub BUILD {
    my ($self, $obj_ID, $arg_ref) = @_;

    $name{$obj_ID} = $arg_ref->{name} || $default_of{name};
    $rank{$obj_ID} = $arg_ref->{rank} || $default_of{rank};
    # repeat for N properties
}

# HoH way
sub BUILD {
    my ($self, $obj_ID, $arg_ref) = @_;

    $data{$obj_ID} = { %default_of, %$arg_ref };
}

##</code><code>##

sub CLONE {
    # fix-up all object ids in the new thread
    for my $old_id ( keys %REGISTRY ) {  
       
        # look under old_id to find the new, cloned reference
        my $object = $REGISTRY{ $old_id };
        my $new_id = refaddr $object;

        # relocate data
        $NAME{ $new_id } = $NAME{ $old_id };
        delete $NAME{ $old_id };
        
        # repeat relocation for N properties

        # update the weak reference to the new, cloned object
        weaken ( $REGISTRY{ $new_id } = $REGISTRY{ $old_id } );
        delete $REGISTRY{ $old_id };
    }
   
    return;
}

##</code><code>##

               Rate NHashObject   HoHObject
NHashObject 51694/s          --        -43%
HoHObject   90761/s         76%          --

##</code><code>##

               Rate NHashObject   HoHObject
NHashObject 50557/s          --         -4%
HoHObject   52932/s          5%          --

##</code><code>##

               Rate   HoHObject NHashObject
HoHObject   60857/s          --         -4%
NHashObject 63625/s          5%          --