> null is what allows us to state things like: > Alice's birth date has not yet been entered in the database (alice.birth_date = null) Better solved with Mayb

> null is what allows us to state things like: > Alice's birth date has not yet been entered in the database (alice.birth_date = null) Better solved with Maybe (see other references in threads) > No orders have yet been placed by this customer (customer.order_list = null) Should be an empty list > The operation succeeded without any errors (error = null) The Either data type is a good solution here, because you can prevent accidentally operating on an invalid result if there was an error > There is no more beer in the fridge (fridge.beer = null) Should be 0 or an empty list