gistfile1.txt

#!/usr/bin/perl -w
package Role;
use Moose::Role;
has '_default_rows' => (is => 'rw', isa => 'Int');
after 'BUILD' => sub {
    my $self = shift;
    $self->_default_rows($self->rows);
};

sub BUILD {}
1;

package BaseClass;
use Moose;
with 'Role';
has 'rows' => (is => 'rw', isa => 'Int', default => 10);
1;
package MyClass;
use Moose;
extends 'BaseClass';
sub BUILD {};

1;

package main;

use strict;
use Test::More tests => 4;

my $o = MyClass->new();

is($o->rows, 10);
is($o->_default_rows, 10);

my $b = BaseClass->new(rows => 1);
is($b->rows, 1);
is($b->_default_rows, 1);