#!/usr/bin/perl -w
use strict;

{
   package Test;
   use Mouse;

   has 'n'  => ( is => 'rw', isa => 'Int', default => 3 );
   has 'n2' => ( is => 'rw', isa => 'Int', lazy => 1,
       default => sub { $_[0]->n + 1 } );

   __PACKAGE__->meta->make_immutable();
}

my $test = Test->new();
print($test->n,  "\n");  # 3
print($test->n2, "\n");  # 4