Roles

Basic problem of OO design

With roles, it's simple:

        package Moonpig::Role::HasCreatedAt;
        use Moose::Role;
        # ABSTRACT: a thing that has the created_at attribute

        use Moonpig::Types qw(Time);

        has created_at => (
          is => 'ro',
          isa => Time,
          default  => sub { Moonpig->env->now },
          init_arg => undef,
        );

Then each of Consumer, Coupon, Credit, and Invoice has:

        with 'Moonpig::Role::HasCreatedAt';