# in your controller you can use
@domain = CreateDomains.new('car.oline.codes').call #=> returns Domain with name 'car' that is the child of `oline.codes`
@domain.web_address.to_s #=> 'car.oline.codes'
You can use your logic for subtree equality to compare the actual web_address
value objects, which are immutable.
You could also see all the 'parent' strings for a given web_address object